Copy in tagged zlib and libpng source.

git-svn-id: http://svn.ghostscript.com/ghostscript/trunk@6394 a1074d23-0009-0410-80fe-cf8c14f379e6

374 files changed, 122567 insertions, 0 deletions

diff --git a/gs/libpng/ANNOUNCE b/gs/libpng/ANNOUNCE
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+++ b/gs/libpng/ANNOUNCE
@@ -0,0 +1,32 @@
+
+Libpng 1.2.8 - December 3, 2004
+
+This is a public release of libpng, intended for use in production codes.
+
+Changes since the last public release (1.2.7):
+
+  Fixed bug in png_text_compress() that would fail to complete a large block.
+  Fixed bug, introduced in libpng-1.2.7, that overruns a buffer during
+    strip alpha operation in png_do_strip_filler().
+  Added PNG_1_2_X definition in pngconf.h
+  #ifdef out png_info_init in png.c and png_read_init in pngread.c (as of 1.3.0)
+  Reduce color_type to a nonalpha type after strip alpha operation in
+    png_do_strip_filler().
+  Revised definitions of PNG_MAX_UINT_32, PNG_MAX_SIZE, and PNG_MAXSUM
+  Fixed (again) definition of PNG_LIBPNG_VER_DLLNUM in png.h (Cosmin).
+  Added PNG_LIBPNG_BUILD_PRIVATE in png.h (Cosmin).
+  Set png_ptr->zstream.data_type to Z_BINARY, to avoid unnecessary detection
+    of data type in deflate (Cosmin).
+  Deprecated but continue to support SPECIALBUILD and PRIVATEBUILD in favor of
+    PNG_LIBPNG_BUILD_SPECIAL_STRING and PNG_LIBPNG_BUILD_PRIVATE_STRING.
+  Despammed mailing addresses by masking "@" with "at".
+  Added scripts/makefile.elf with supporting code in pngconf.h for symbol
+    versioning (John Bowler).
+  Added projects/visualc71 (Simon-pierre).
+
+Send comments/corrections/commendations to
+png-implement at ccrc.wustl.edu (subscription required; write to
+majordomo at ccrc.wustl.edu with "subscribe png-implement" in the message)
+or to glennrp at users.sourceforge.net
+
+Glenn R-P
diff --git a/gs/libpng/CHANGES b/gs/libpng/CHANGES
new file mode 100644
index 000000000..90c816e35
--- /dev/null
+++ b/gs/libpng/CHANGES
@@ -0,0 +1,1419 @@
+
+CHANGES - changes for libpng
+
+version 0.2
+  added reader into png.h
+  fixed small problems in stub file
+
+version 0.3
+  added pull reader
+  split up pngwrite.c to several files
+  added pnglib.txt
+  added example.c
+  cleaned up writer, adding a few new tranformations
+  fixed some bugs in writer
+  interfaced with zlib 0.5
+  added K&R support
+  added check for 64 KB blocks for 16 bit machines
+
+version 0.4
+  cleaned up code and commented code
+  simplified time handling into png_time
+  created png_color_16 and png_color_8 to handle color needs
+  cleaned up color type defines
+  fixed various bugs
+  made various names more consistant
+  interfaced with zlib 0.71
+  cleaned up zTXt reader and writer (using zlib's Reset functions)
+  split transformations into pngrtran.c and pngwtran.c
+
+version 0.5
+  interfaced with zlib 0.8
+  fixed many reading and writing bugs
+  saved using 3 spaces instead of tabs
+
+version 0.6
+  added png_large_malloc() and png_large_free()
+  added png_size_t
+  cleaned up some compiler warnings
+  added png_start_read_image()
+
+version 0.7
+  cleaned up lots of bugs
+  finished dithering and other stuff
+  added test program
+  changed name from pnglib to libpng
+
+version 0.71 [June, 1995]
+  changed pngtest.png for zlib 0.93
+  fixed error in libpng.txt and example.c
+
+version 0.8
+  cleaned up some bugs
+  added png_set_filler()
+  split up pngstub.c into pngmem.c, pngio.c, and pngerror.c
+  added #define's to remove unwanted code
+  moved png_info_init() to png.c
+  added old_size into png_realloc()
+  added functions to manually set filtering and compression info
+  changed compression parameters based on image type
+  optimized filter selection code
+  added version info
+  changed external functions passing floats to doubles (k&r problems?)
+  put all the configurable stuff in pngconf.h
+  enabled png_set_shift to work with paletted images on read
+  added png_read_update_info() - updates info structure with
+     transformations
+
+version 0.81 [August, 1995]
+  incorporated Tim Wegner's medium model code (thanks, Tim)
+
+version 0.82 [September, 1995]
+  [unspecified changes]
+
+version 0.85 [December, 1995]
+  added more medium model code (almost everything's a far)
+  added i/o, error, and memory callback functions
+  fixed some bugs (16 bit, 4 bit interlaced, etc.)
+  added first run progressive reader (barely tested)
+
+version 0.86 [January, 1996]
+  fixed bugs
+  improved documentation
+
+version 0.87 [January, 1996]
+  fixed medium model bugs
+  fixed other bugs introduced in 0.85 and 0.86
+  added some minor documentation
+
+version 0.88 [January, 1996]
+  fixed progressive bugs
+  replaced tabs with spaces
+  cleaned up documentation
+  added callbacks for read/write and warning/error functions
+
+version 0.89 [July, 1996]
+  added new initialization API to make libpng work better with shared libs
+     we now have png_create_read_struct(), png_create_write_struct(),
+     png_create_info_struct(), png_destroy_read_struct(), and
+     png_destroy_write_struct() instead of the separate calls to
+     malloc and png_read_init(), png_info_init(), and png_write_init()
+  changed warning/error callback functions to fix bug - this means you
+     should use the new initialization API if you were using the old
+     png_set_message_fn() calls, and that the old API no longer exists
+     so that people are aware that they need to change their code
+  changed filter selection API to allow selection of multiple filters
+     since it didn't work in previous versions of libpng anyways
+  optimized filter selection code
+  fixed png_set_background() to allow using an arbitrary RGB color for
+     paletted images
+  fixed gamma and background correction for paletted images, so
+     png_correct_palette is not needed unless you are correcting an
+     external palette (you will need to #define PNG_CORRECT_PALETTE_SUPPORTED
+     in pngconf.h) - if nobody uses this, it may disappear in the future.
+  fixed bug with Borland 64K memory allocation (Alexander Lehmann)
+  fixed bug in interlace handling (Smarasderagd, I think)
+  added more error checking for writing and image to reduce invalid files
+  separated read and write functions so that they won't both be linked
+     into a binary when only reading or writing functionality is used
+  new pngtest image also has interlacing and zTXt
+  updated documentation to reflect new API
+
+version 0.90 [January, 1997]
+  made CRC errors/warnings on critical and ancillary chunks configurable
+  libpng will use the zlib CRC routines by (compile-time) default
+  changed DOS small/medium model memory support - needs zlib 1.04 (Tim Wegner)
+  added external C++ wrapper statements to png.h (Gilles Dauphin)
+  allow PNG file to be read when some or all of file signature has already
+     been read from the beginning of the stream.  ****This affects the size
+     of info_struct and invalidates all programs that use a shared libpng****
+  fixed png_filler() declarations
+  fixed? background color conversions
+  fixed order of error function pointers to match documentation
+  current chunk name is now available in png_struct to reduce the number
+     of nearly identical error messages (will simplify multi-lingual
+     support when available)
+  try to get ready for unknown-chunk callback functions:
+     - previously read critical chunks are flagged, so the chunk handling
+       routines can determine if the chunk is in the right place
+     - all chunk handling routines have the same prototypes, so we will
+       be able to handle all chunks via a callback mechanism
+  try to fix Linux "setjmp" buffer size problems
+  removed png_large_malloc, png_large_free, and png_realloc functions.
+
+version 0.95 [March, 1997]
+  fixed bug in pngwutil.c allocating "up_row" twice and "avg_row" never
+  fixed bug in PNG file signature compares when start != 0
+  changed parameter type of png_set_filler(...filler...) from png_byte
+     to png_uint_32
+  added test for MACOS to ensure that both math.h and fp.h are not #included
+  added macros for libpng to be compiled as a Windows DLL (Andreas Kupries)
+  added "packswap" transformation, which changes the endianness of
+     packed-pixel bytes (Kevin Bracey)
+  added "strip_alpha" transformation, which removes the alpha channel of
+     input images without using it (not neccesarily a good idea)
+  added "swap_alpha" transformation, which puts the alpha channel in front
+     of the color bytes instead of after
+  removed all implicit variable tests which assume NULL == 0 (I think)
+  changed several variables to "png_size_t" to show 16/32-bit limitations
+  added new pCAL chunk read/write support
+  added experimental filter selection weighting (Greg Roelofs)
+  removed old png_set_rgbx() and png_set_xrgb() functions that have been
+     obsolete for about 2 years now (use png_set_filler() instead)
+  added macros to read 16- and 32-bit ints directly from buffer, to be
+     used only on those systems that support it (namely PowerPC and 680x0)
+     With some testing, this may become the default for MACOS/PPC systems.
+  only calculate CRC on data if we are going to use it
+  added macros for zTXt compression type PNG_zTXt_COMPRESSION_???
+  added macros for simple libpng debugging output selectable at compile time
+  removed PNG_READ_END_MODE in progressive reader (Smarasderagd)
+  more description of info_struct in libpng.txt and png.h
+  more instructions in example.c
+  more chunk types tested in pngtest.c
+  renamed pngrcb.c to pngset.c, and all png_read_<chunk> functions to be
+     png_set_<chunk>.  We now have corresponding png_get_<chunk>
+     functions in pngget.c to get infomation in info_ptr.  This isolates
+     the application from the internal organization of png_info_struct
+     (good for shared library implementations).
+
+version 0.96 [May, 1997]
+  fixed serious bug with < 8bpp images introduced in 0.95
+  fixed 256-color transparency bug (Greg Roelofs)
+  fixed up documentation (Greg Roelofs, Laszlo Nyul)
+  fixed "error" in pngconf.h for Linux setjmp() behaviour
+  fixed DOS medium model support (Tim Wegner)
+  fixed png_check_keyword() for case with error in static string text
+  added read of CRC after IEND chunk for embedded PNGs (Laszlo Nyul)
+  added typecasts to quiet compiler errors
+  added more debugging info
+
+version 0.97 [January, 1998]
+  removed PNG_USE_OWN_CRC capability
+  relocated png_set_crc_action from pngrutil.c to pngrtran.c
+  fixed typecasts of "new_key", etc. (Andreas Dilger)
+  added RFC 1152 [sic] date support
+  fixed bug in gamma handling of 4-bit grayscale
+  added 2-bit grayscale gamma handling (Glenn R-P)
+  added more typecasts. 65536L becomes (png_uint_32)65536L, etc. (Glenn R-P)
+  minor corrections in libpng.txt
+  added simple sRGB support (Glenn R-P)
+  easier conditional compiling, e.g. define PNG_READ/WRITE_NOT_FULLY_SUPPORTED;
+     all configurable options can be selected from command-line instead
+     of having to edit pngconf.h (Glenn R-P)
+  fixed memory leak in pngwrite.c (free info_ptr->text) (Glenn R-P)
+  added more conditions for png_do_background, to avoid changing
+     black pixels to background when a background is supplied and
+     no pixels are transparent
+  repaired PNG_NO_STDIO behaviour
+  tested NODIV support and made it default behaviour (Greg Roelofs)
+  added "-m" option and PNGTEST_DEBUG_MEMORY to pngtest (John Bowler)
+  regularized version numbering scheme and bumped shared-library major
+     version number to 2 to avoid problems with libpng 0.89 apps (Greg Roelofs)
+
+version 0.98 [January, 1998]
+  cleaned up some typos in libpng.txt and in code documentation
+  fixed memory leaks in pCAL chunk processing (Glenn R-P and John Bowler)
+  cosmetic change "display_gamma" to "screen_gamma" in pngrtran.c
+  changed recommendation about file_gamma for PC images to .51 from .45,
+     in example.c and libpng.txt, added comments to distinguish between
+     screen_gamma, viewing_gamma, and display_gamma.
+  changed all references to RFC1152 to read RFC1123 and changed the
+     PNG_TIME_RFC1152_SUPPORTED macro to PNG_TIME_RFC1123_SUPPORTED
+  added png_invert_alpha capability (Glenn R-P -- suggestion by Jon Vincent)
+  changed srgb_intent from png_byte to int to avoid compiler bugs
+
+version 0.99 [January 30, 1998]
+  free info_ptr->text instead of end_info_ptr->text in pngread.c (John Bowler)
+  fixed a longstanding "packswap" bug in pngtrans.c
+  fixed some inconsistencies in pngconf.h that prevented compiling with
+     PNG_READ_GAMMA_SUPPORTED and PNG_READ_hIST_SUPPORTED undefined
+  fixed some typos and made other minor rearrangement of libpng.txt (Andreas)
+  changed recommendation about file_gamma for PC images to .50 from .51 in
+     example.c and libpng.txt, and changed file_gamma for sRGB images to .45
+  added a number of functions to access information from the png structure
+     png_get_image_height(), etc. (Glenn R-P, suggestion by Brad Pettit)
+  added TARGET_MACOS similar to zlib-1.0.8
+  define PNG_ALWAYS_EXTERN when __MWERKS__ && WIN32 are defined
+  added type casting to all png_malloc() function calls
+version 0.99a [January 31, 1998]
+  Added type casts and parentheses to all returns that return a value.(Tim W.)
+version 0.99b [February 4, 1998]
+  Added type cast png_uint_32 on malloc function calls where needed.
+  Changed type of num_hist from png_uint_32 to int (same as num_palette).
+  Added checks for rowbytes overflow, in case png_size_t is less than 32 bits.
+  Renamed makefile.elf to makefile.lnx.
+version 0.99c [February 7, 1998]
+  More type casting.  Removed erroneous overflow test in pngmem.c.
+  Added png_buffered_memcpy() and png_buffered_memset(), apply them to rowbytes.
+  Added UNIX manual pages libpng.3 (incorporating libpng.txt) and  png.5.
+version 0.99d [February 11, 1998]
+  Renamed "far_to_near()" "png_far_to_near()"
+  Revised libpng.3
+  Version 99c "buffered" operations didn't work as intended.  Replaced them
+    with png_memcpy_check() and png_memset_check().
+  Added many "if (png_ptr == NULL) return" to quell compiler warnings about
+    unused png_ptr, mostly in pngget.c and pngset.c.
+  Check for overlength tRNS chunk present when indexed-color PLTE is read.
+  Cleaned up spelling errors in libpng.3/libpng.txt
+  Corrected a problem with png_get_tRNS() which returned undefined trans array
+version 0.99e [February 28, 1998]
+  Corrected png_get_tRNS() again.
+  Add parentheses for easier reading of pngget.c, fixed "||" should be "&&".
+  Touched up example.c to make more of it compileable, although the entire
+    file still can't be compiled (Willem van Schaik)
+  Fixed a bug in png_do_shift() (Bryan Tsai)
+  Added a space in png.h prototype for png_write_chunk_start()
+  Replaced pngtest.png with one created with zlib 1.1.1
+  Changed pngtest to report PASS even when file size is different (Jean-loup G.)
+  Corrected some logic errors in png_do_invert_alpha() (Chris Patterson)
+version 0.99f [March 5, 1998]
+  Corrected a bug in pngpread() introduced in version 99c (Kevin Bracey)
+  Moved makefiles into a "scripts" directory, and added INSTALL instruction file
+  Added makefile.os2 and pngos2.def (A. Zabolotny) and makefile.s2x (W. Sebok)
+  Added pointers to "note on libpng versions" in makefile.lnx and README
+  Added row callback feature when reading and writing nonprogressive rows
+     and added a test of this feature in pngtest.c
+  Added user transform callbacks, with test of the feature in pngtest.c
+version 0.99g [March 6, 1998, morning]
+  Minor changes to pngtest.c to suppress compiler warnings.
+  Removed "beta" language from documentation.
+version 0.99h [March 6, 1998, evening]
+  Minor changes to previous minor changes to pngtest.c
+  Changed PNG_READ_NOT_FULLY_SUPPORTED to PNG_READ_TRANSFORMS_NOT_SUPPORTED
+  and added PNG_PROGRESSIVE_READ_NOT_SUPPORTED macro
+  Added user transform capability
+
+version 1.00 [March 7, 1998]
+  Changed several typedefs in pngrutil.c
+  Added makefile.wat (Pawel Mrochen), updated makefile.tc3 (Willem van Schaik)
+  replaced "while(1)" with "for(;;)"
+  added PNGARG() to prototypes in pngtest.c and removed some prototypes
+  updated some of the makefiles (Tom Lane)
+  changed some typedefs (s_start, etc.) in pngrutil.c
+  fixed dimensions of "short_months" array in pngwrite.c
+  Replaced ansi2knr.c with the one from jpeg-v6
+
+version 1.0.0 [March 8, 1998]
+  Changed name from 1.00 to 1.0.0 (Adam Costello)
+  Added smakefile.ppc (with SCOPTIONS.ppc) for Amiga PPC (Andreas Kleinert)
+version 1.0.0a [March 9, 1998]
+  Fixed three bugs in pngrtran.c to make gamma+background handling consistent
+  (Greg Roelofs)
+  Changed format of the PNG_LIBPNG_VER integer to xyyzz instead of xyz
+  for major, minor, and bugfix releases.  This is 10001. (Adam Costello,
+  Tom Lane)
+  Make months range from 1-12 in png_convert_to_rfc1123
+version 1.0.0b [March 13, 1998]
+  Quieted compiler complaints about two empty "for" loops in pngrutil.c
+  Minor changes to makefile.s2x
+  Removed #ifdef/#endif around a png_free() in pngread.c
+
+version 1.0.1 [March 14, 1998]
+  Changed makefile.s2x to reduce security risk of using a relative pathname
+  Fixed some typos in the documentation (Greg).
+  Fixed a problem with value of "channels" returned by png_read_update_info()
+version 1.0.1a [April 21, 1998]
+  Optimized Paeth calculations by replacing abs() function calls with intrinsics
+  plus other loop optimizations. Improves avg decoding speed by about 20%.
+  Commented out i386istic "align" compiler flags in makefile.lnx.
+  Reduced the default warning level in some makefiles, to make them consistent.
+  Removed references to IJG and JPEG in the ansi2knr.c copyright statement.
+  Fixed a bug in png_do_strip_filler with XXRRGGBB => RRGGBB transformation.
+  Added grayscale and 16-bit capability to png_do_read_filler().
+  Fixed a bug in pngset.c, introduced in version 0.99c, that sets rowbytes
+    too large when writing an image with bit_depth < 8 (Bob Dellaca).
+  Corrected some bugs in the experimental weighted filtering heuristics.
+  Moved a misplaced pngrutil code block that truncates tRNS if it has more
+    than num_palette entries -- test was done before num_palette was defined.
+  Fixed a png_convert_to_rfc1123() bug that converts day 31 to 0 (Steve Eddins).
+  Changed compiler flags in makefile.wat for better optimization (Pawel Mrochen).
+version 1.0.1b [May 2, 1998]
+  Relocated png_do_gray_to_rgb() within png_do_read_transformations() (Greg).
+  Relocated the png_composite macros from pngrtran.c to png.h (Greg).
+  Added makefile.sco (contributed by Mike Hopkirk).
+  Fixed two bugs (missing definitions of "istop") introduced in libpng-1.0.1a.
+  Fixed a bug in pngrtran.c that would set channels=5 under some circumstances.
+  More work on the Paeth-filtering, achieving imperceptible speedup (A Kleinert).
+  More work on loop optimization which may help when compiled with C++ compilers.
+  Added warnings when people try to use transforms they've defined out.
+  Collapsed 4 "i" and "c" loops into single "i" loops in pngrtran and pngwtran.
+  Revised paragraph about png_set_expand() in libpng.txt and libpng.3 (Greg)
+version 1.0.1c [May 11, 1998]
+  Fixed a bug in pngrtran.c (introduced in libpng-1.0.1a) where the masks for
+    filler bytes should have been 0xff instead of 0xf.
+  Added max_pixel_depth=32 in pngrutil.c when using FILLER with palette images.
+  Moved PNG_WRITE_WEIGHTED_FILTER_SUPPORTED and PNG_WRITE_FLUSH_SUPPORTED
+    out of the PNG_WRITE_TRANSFORMS_NOT_SUPPORTED block of pngconf.h
+  Added "PNG_NO_WRITE_TRANSFORMS" etc., as alternatives for *_NOT_SUPPORTED,
+    for consistency, in pngconf.h
+  Added individual "ifndef PNG_NO_[CAPABILITY]" in pngconf.h to make it easier
+    to remove unwanted capabilities via the compile line
+  Made some corrections to grammar (which, it's) in documentation (Greg).
+  Corrected example.c, use of row_pointers in png_write_image().
+version 1.0.1d [May 24, 1998]
+  Corrected several statements that used side effects illegally in pngrutil.c
+    and pngtrans.c, that were introduced in version 1.0.1b
+  Revised png_read_rows() to avoid repeated if-testing for NULL (A Kleinert)
+  More corrections to example.c, use of row_pointers in png_write_image()
+    and png_read_rows().
+  Added pngdll.mak and pngdef.pas to scripts directory, contributed by
+    Bob Dellaca, to make a png32bd.dll with Borland C++ 4.5
+  Fixed error in example.c with png_set_text: num_text is 3, not 2 (Guido V.)
+  Changed several loops from count-down to count-up, for consistency.
+version 1.0.1e [June 6, 1998]
+  Revised libpng.txt and libpng.3 description of png_set_read|write_fn(), and
+    added warnings when people try to set png_read_fn and png_write_fn in
+    the same structure.
+  Added a test such that png_do_gamma will be done when num_trans==0
+    for truecolor images that have defined a background.  This corrects an
+    error that was introduced in libpng-0.90 that can cause gamma processing
+    to be skipped.
+  Added tests in png.h to include "trans" and "trans_values" in structures
+    when PNG_READ_BACKGROUND_SUPPORTED or PNG_READ_EXPAND_SUPPORTED is defined.
+  Add png_free(png_ptr->time_buffer) in png_destroy_read_struct()
+  Moved png_convert_to_rfc_1123() from pngwrite.c to png.c
+  Added capability for user-provided malloc_fn() and free_fn() functions,
+    and revised pngtest.c to demonstrate their use, replacing the
+    PNGTEST_DEBUG_MEM feature.
+  Added makefile.w32, for Microsoft C++ 4.0 and later (Tim Wegner).
+
+version 1.0.2 [June 14, 1998]
+  Fixed two bugs in makefile.bor .
+version 1.0.2a [December 30, 1998]
+  Replaced and extended code that was removed from png_set_filler() in 1.0.1a.
+  Fixed a bug in png_do_filler() that made it fail to write filler bytes in
+    the left-most pixel of each row (Kevin Bracey).
+  Changed "static pngcharp tIME_string" to "static char tIME_string[30]"
+    in pngtest.c (Duncan Simpson).
+  Fixed a bug in pngtest.c that caused pngtest to try to write a tIME chunk
+    even when no tIME chunk was present in the source file.
+  Fixed a problem in pngrutil.c: gray_to_rgb didn't always work with 16-bit.
+  Fixed a problem in png_read_push_finish_row(), which would not skip some
+    passes that it should skip, for images that are less than 3 pixels high.
+  Interchanged the order of calls to png_do_swap() and png_do_shift()
+    in pngwtran.c (John Cromer).
+  Added #ifdef PNG_DEBUG/#endif surrounding use of PNG_DEBUG in png.h .
+  Changed "bad adaptive filter type" from error to warning in pngrutil.c .
+  Fixed a documentation error about default filtering with 8-bit indexed-color.
+  Separated the PNG_NO_STDIO macro into PNG_NO_STDIO and PNG_NO_CONSOLE_IO
+    (L. Peter Deutsch).
+  Added png_set_rgb_to_gray() and png_get_rgb_to_gray_status() functions.
+  Added png_get_copyright() and png_get_header_version() functions.
+  Revised comments on png_set_progressive_read_fn() in libpng.txt and example.c
+  Added information about debugging in libpng.txt and libpng.3 .
+  Changed "ln -sf" to "ln -s -f" in makefile.s2x, makefile.lnx, and makefile.sco.
+  Removed lines after Dynamic Dependencies" in makefile.aco .
+  Revised makefile.dec to make a shared library (Jeremie Petit).
+  Removed trailing blanks from all files.
+version 1.0.2a [January 6, 1999]
+  Removed misplaced #endif and #ifdef PNG_NO_EXTERN near the end of png.h
+  Added "if" tests to silence complaints about unused png_ptr in png.h and png.c
+  Changed "check_if_png" function in example.c to return true (nonzero) if PNG.
+  Changed libpng.txt to demonstrate png_sig_cmp() instead of png_check_sig()
+    which is obsolete.
+
+version 1.0.3 [January 14, 1999]
+  Added makefile.hux, for Hewlett Packard HPUX 10.20 and 11.00 (Jim Rice)
+  Added a statement of Y2K compliance in png.h, libpng.3, and Y2KINFO.
+version 1.0.3a [August 12, 1999]
+  Added check for PNG_READ_INTERLACE_SUPPORTED in pngread.c; issue a warning
+     if an attempt is made to read an interlaced image when it's not supported.
+  Added check if png_ptr->trans is defined before freeing it in pngread.c
+  Modified the Y2K statement to include versions back to version 0.71
+  Fixed a bug in the check for valid IHDR bit_depth/color_types in pngrutil.c
+  Modified makefile.wat (added -zp8 flag, ".symbolic", changed some comments)
+  Replaced leading blanks with tab characters in makefile.hux
+  Changed "dworkin.wustl.edu" to "ccrc.wustl.edu" in various documents.
+  Changed (float)red and (float)green to (double)red, (double)green
+     in png_set_rgb_to_gray() to avoid "promotion" problems in AIX.
+  Fixed a bug in pngconf.h that omitted <stdio.h> when PNG_DEBUG==0 (K Bracey).
+  Reformatted libpng.3 and libpngpf.3 with proper fonts (script by J. vanZandt).
+  Updated documentation to refer to the PNG-1.2 specification.
+  Removed ansi2knr.c and left pointers to the latest source for ansi2knr.c
+    in makefile.knr, INSTALL, and README (L. Peter Deutsch)
+  Fixed bugs in calculation of the length of rowbytes when adding alpha
+    channels to 16-bit images, in pngrtran.c (Chris Nokleberg)
+  Added function png_set_user_transform_info() to store user_transform_ptr,
+    user_depth, and user_channels into the png_struct, and a function
+    png_get_user_transform_ptr() to retrieve the pointer (Chris Nokleberg)
+  Added function png_set_empty_plte_permitted() to make libpng useable
+    in MNG applications.
+  Corrected the typedef for png_free_ptr in png.h (Jesse Jones).
+  Correct gamma with srgb is 45455 instead of 45000 in pngrutil.c, to be
+    consistent with PNG-1.2, and allow variance of 500 before complaining.
+  Added assembler code contributed by Intel in file pngvcrd.c and modified
+    makefile.w32 to use it (Nirav Chhatrapati, INTEL Corporation, Gilles Vollant)
+  Changed "ln -s -f" to "ln -f -s" in the makefiles to make Solaris happy.
+  Added some aliases for png_set_expand() in pngrtran.c, namely
+    png_set_expand_PLTE(), png_set_expand_depth(), and png_set_expand_tRNS()
+    (Greg Roelofs, in "PNG: The Definitive Guide").
+  Added makefile.beo for BEOS on X86, contributed by Sander Stok.
+version 1.0.3b [August 26, 1999]
+  Replaced 2147483647L several places with PNG_MAX_UINT macro, defined in png.h
+  Changed leading blanks to tabs in all makefiles.
+  Define PNG_USE_PNGVCRD in makefile.w32, to get MMX assembler code.
+  Made alternate versions of  png_set_expand() in pngrtran.c, namely
+    png_set_gray_1_2_4_to_8, png_set_palette_to_rgb, and png_set_tRNS_to_alpha
+    (Greg Roelofs, in "PNG: The Definitive Guide").  Deleted the 1.0.3a aliases.
+  Relocated start of 'extern "C"' block in png.h so it doesn't include pngconf.h
+  Revised calculation of num_blocks in pngmem.c to avoid a potentially
+    negative shift distance, whose results are undefined in the C language.
+  Added a check in pngset.c to prevent writing multiple tIME chunks.
+  Added a check in pngwrite.c to detect invalid small window_bits sizes.
+version 1.0.3d [September 4, 1999]
+  Fixed type casting of igamma in pngrutil.c
+  Added new png_expand functions to scripts/pngdef.pas and pngos2.def
+  Added a demo read_user_transform_fn that examines the row filters in pngtest.c
+
+version 1.0.4 [September 24, 1999]
+  Define PNG_ALWAYS_EXTERN in pngconf.h if __STDC__ is defined
+  Delete #define PNG_INTERNAL and include "png.h" from pngasmrd.h
+  Made several minor corrections to pngtest.c
+  Renamed the makefiles with longer but more user friendly extensions.
+  Copied the PNG copyright and license to a separate LICENSE file.
+  Revised documentation, png.h, and example.c to remove reference to
+    "viewing_gamma" which no longer appears in the PNG specification.
+  Revised pngvcrd.c to use MMX code for interlacing only on the final pass.
+  Updated pngvcrd.c to use the faster C filter algorithms from libpng-1.0.1a
+  Split makefile.win32vc into two versions, makefile.vcawin32 (uses MMX
+    assembler code) and makefile.vcwin32 (doesn't).
+  Added a CPU timing report to pngtest.c (enabled by defining PNGTEST_TIMING)
+  Added a copy of pngnow.png to the distribution.
+version 1.0.4a [September 25, 1999]
+  Increase max_pixel_depth in pngrutil.c if a user transform needs it.
+  Changed several division operations to right-shifts in pngvcrd.c
+version 1.0.4b [September 30, 1999]
+  Added parentheses in line 3732 of pngvcrd.c
+  Added a comment in makefile.linux warning about buggy -O3 in pgcc 2.95.1
+version 1.0.4c [October 1, 1999]
+  Added a "png_check_version" function in png.c and pngtest.c that will generate
+    a helpful compiler error if an old png.h is found in the search path.
+  Changed type of png_user_transform_depth|channels from int to png_byte.
+version 1.0.4d [October 6, 1999]
+  Changed 0.45 to 0.45455 in png_set_sRGB()
+  Removed unused PLTE entries from pngnow.png
+  Re-enabled some parts of pngvcrd.c (png_combine_row) that work properly.
+version 1.0.4e [October 10, 1999]
+  Fixed sign error in pngvcrd.c (Greg Roelofs)
+  Replaced some instances of memcpy with simple assignments in pngvcrd (GR-P)
+version 1.0.4f [October 15, 1999]
+  Surrounded example.c code with #if 0 .. #endif to prevent people from
+    inadvertently trying to compile it.
+  Changed png_get_header_version() from a function to a macro in png.h
+  Added type casting mostly in pngrtran.c and pngwtran.c
+  Removed some pointless "ptr = NULL" in pngmem.c
+  Added a "contrib" directory containing the source code from Greg's book.
+
+version 1.0.5 [October 15, 1999]
+  Minor editing of the INSTALL and README files.
+version 1.0.5a [October 23, 1999]
+  Added contrib/pngsuite and contrib/pngminus (Willem van Schaik)
+  Fixed a typo in the png_set_sRGB() function call in example.c (Jan Nijtmans)
+  Further optimization and bugfix of pngvcrd.c
+  Revised pngset.c so that it does not allocate or free memory in the user's
+    text_ptr structure.  Instead, it makes its own copy.
+  Created separate write_end_info_struct in pngtest.c for a more severe test.
+  Added code in pngwrite.c to free info_ptr->text[i].key to stop a memory leak.
+version 1.0.5b [November 23, 1999]
+  Moved PNG_FLAG_HAVE_CHUNK_HEADER, PNG_FLAG_BACKGROUND_IS_GRAY and
+    PNG_FLAG_WROTE_tIME from flags to mode.
+  Added png_write_info_before_PLTE() function.
+  Fixed some typecasting in contrib/gregbook/*.c
+  Updated scripts/makevms.com and added makevms.com to contrib/gregbook
+    and contrib/pngminus (Martin Zinser)
+version 1.0.5c [November 26, 1999]
+  Moved png_get_header_version from png.h to png.c, to accomodate ansi2knr.
+  Removed all global arrays (according to PNG_NO_GLOBAL_ARRAYS macro), to
+    accomodate making DLL's: Moved usr_png_ver from global variable to function
+    png_get_header_ver() in png.c.  Moved png_sig to png_sig_bytes in png.c and
+    eliminated use of png_sig in pngwutil.c.  Moved the various png_CHNK arrays
+    into pngtypes.h.  Eliminated use of global png_pass arrays.  Declared the
+    png_CHNK and png_pass arrays to be "const".  Made the global arrays
+    available to applications (although none are used in libpng itself) when
+    PNG_NO_GLOBAL_ARRAYS is not defined or when PNG_GLOBAL_ARRAYS is defined.
+  Removed some extraneous "-I" from contrib/pngminus/makefile.std
+  Changed the PNG_sRGB_INTENT macros in png.h to be consistent with PNG-1.2.
+  Change PNG_SRGB_INTENT to PNG_sRGB_INTENT in libpng.txt and libpng.3
+version 1.0.5d [November 29, 1999]
+  Add type cast (png_const_charp) two places in png.c
+  Eliminated pngtypes.h; use macros instead to declare PNG_CHNK arrays.
+  Renamed "PNG_GLOBAL_ARRAYS" to "PNG_USE_GLOBAL_ARRAYS" and made available
+    to applications a macro "PNG_USE_LOCAL_ARRAYS".
+  #ifdef out all the new declarations when PNG_USE_GLOBAL_ARRAYS is defined.
+  Added PNG_EXPORT_VAR macro to accommodate making DLL's.
+version 1.0.5e [November 30, 1999]
+  Added iCCP, iTXt, and sPLT support; added "lang" member to the png_text
+    structure; refactored the inflate/deflate support to make adding new chunks
+    with trailing compressed parts easier in the future, and added new functions
+    png_free_iCCP, png_free_pCAL, png_free_sPLT, png_free_text, png_get_iCCP,
+    png_get_spalettes, png_set_iCCP, png_set_spalettes (Eric S. Raymond).
+  NOTE: Applications that write text chunks MUST define png_text->lang
+    before calling png_set_text(). It must be set to NULL if you want to
+    write tEXt or zTXt chunks.  If you want your application to be able to
+    run with older versions of libpng, use
+
+      #ifdef PNG_iTXt_SUPPORTED
+         png_text[i].lang = NULL;
+      #endif
+
+  Changed png_get_oFFs() and png_set_oFFs() to use signed rather than unsigned
+    offsets (Eric S. Raymond).
+  Combined PNG_READ_cHNK_SUPPORTED and PNG_WRITE_cHNK_SUPPORTED macros into
+    PNG_cHNK_SUPPORTED and combined the three types of PNG_text_SUPPORTED
+    macros, leaving the separate macros also available.
+  Removed comments on #endifs at the end of many short, non-nested #if-blocks.
+version 1.0.5f [December 6, 1999]
+  Changed makefile.solaris to issue a warning about potential problems when
+    the ucb "ld" is in the path ahead of the ccs "ld".
+  Removed "- [date]" from the "synopsis" line in libpng.3 and libpngpf.3.
+  Added sCAL chunk support (Eric S. Raymond).
+version 1.0.5g [December 7, 1999]
+  Fixed "png_free_spallettes" typo in png.h
+  Added code to handle new chunks in pngpread.c
+  Moved PNG_CHNK string macro definitions outside of PNG_NO_EXTERN block
+  Added "translated_key" to png_text structure and png_write_iTXt().
+  Added code in pngwrite.c to work around a newly discovered zlib bug.
+version 1.0.5h [December 10, 1999]
+  NOTE: regarding the note for version 1.0.5e, the following must also
+    be included in your code:
+        png_text[i].translated_key = NULL;
+  Unknown chunk handling is now supported.
+  Option to eliminate all floating point support was added.  Some new
+    fixed-point functions such as png_set_gAMA_fixed() were added.
+  Expanded tabs and removed trailing blanks in source files.
+version 1.0.5i [December 13, 1999]
+  Added some type casts to silence compiler warnings.
+  Renamed "png_free_spalette" to "png_free_spalettes" for consistency.
+  Removed leading blanks from a #define in pngvcrd.c
+  Added some parameters to the new png_set_keep_unknown_chunks() function.
+  Added a test for up->location != 0 in the first instance of writing
+    unknown chunks in pngwrite.c
+  Changed "num" to "i" in png_free_spalettes() and png_free_unknowns() to
+    prevent recursion.
+  Added png_free_hIST() function.
+  Various patches to fix bugs in the sCAL and integer cHRM processing,
+    and to add some convenience macros for use with sCAL.
+version 1.0.5j [December 21, 1999]
+  Changed "unit" parameter of png_write_sCAL from png_byte to int, to work
+    around buggy compilers.
+  Added new type "png_fixed_point" for integers that hold float*100000 values
+  Restored backward compatibility of tEXt/zTXt chunk processing:
+    Restored the first four members of png_text to the same order as v.1.0.5d.
+    Added members "lang_key" and "itxt_length" to png_text struct.  Set
+    text_length=0 when "text" contains iTXt data.  Use the "compression"
+    member to distinguish among tEXt/zTXt/iTXt types.  Added
+    PNG_ITXT_COMPRESSION_NONE (1) and PNG_ITXT_COMPRESSION_zTXt(2) macros.
+    The "Note" above, about backward incompatibility of libpng-1.0.5e, no
+    longer applies.
+  Fixed png_read|write_iTXt() to read|write parameters in the right order,
+    and to write the iTXt chunk after IDAT if it appears in the end_ptr.
+  Added pnggccrd.c, version of pngvcrd.c Intel assembler for gcc (Greg Roelofs)
+  Reversed the order of trying to write floating-point and fixed-point gAMA.
+version 1.0.5k [December 27, 1999]
+  Added many parentheses, e.g., "if (a && b & c)" becomes "if (a && (b & c))"
+  Added png_handle_as_unknown() function (Glenn)
+  Added png_free_chunk_list() function and chunk_list and num_chunk_list members
+    of png_ptr.
+  Eliminated erroneous warnings about multiple sPLT chunks and sPLT-after-PLTE.
+  Fixed a libpng-1.0.5h bug in pngrutil.c that was issuing erroneous warnings
+    about ignoring incorrect gAMA with sRGB (gAMA was in fact not ignored)
+  Added png_free_tRNS(); png_set_tRNS() now malloc's its own trans array (ESR).
+  Define png_get_int_32 when oFFs chunk is supported as well as when pCAL is.
+  Changed type of proflen from png_int_32 to png_uint_32 in png_get_iCCP().
+version 1.0.5l [January 1, 2000]
+  Added functions png_set_read_user_chunk_fn() and png_get_user_chunk_ptr()
+    for setting a callback function to handle unknown chunks and for
+    retrieving the associated user pointer (Glenn).
+version 1.0.5m [January 7, 2000]
+  Added high-level functions png_read_png(), png_write_png(), png_free_pixels().
+version 1.0.5n [January 9, 2000]
+  Added png_free_PLTE() function, and modified png_set_PLTE() to malloc its
+    own memory for info_ptr->palette.  This makes it safe for the calling
+    application to free its copy of the palette any time after it calls
+    png_set_PLTE().
+version 1.0.5o [January 20, 2000]
+  Cosmetic changes only (removed some trailing blanks and TABs)
+version 1.0.5p [January 31, 2000]
+  Renamed pngdll.mak to makefile.bd32
+  Cosmetic changes in pngtest.c
+version 1.0.5q [February 5, 2000]
+  Relocated the makefile.solaris warning about PATH problems.
+  Fixed pngvcrd.c bug by pushing/popping registers in mmxsupport (Bruce Oberg)
+  Revised makefile.gcmmx
+  Added PNG_SETJMP_SUPPORTED, PNG_SETJMP_NOT_SUPPORTED, and PNG_ABORT() macros
+version 1.0.5r [February 7, 2000]
+  Removed superfluous prototype for png_get_itxt from png.h
+  Fixed a bug in pngrtran.c that improperly expanded the background color.
+  Return *num_text=0 from png_get_text() when appropriate, and fix documentation
+    of png_get_text() in libpng.txt/libpng.3.
+version 1.0.5s [February 18, 2000]
+  Added "png_jmp_env()" macro to pngconf.h, to help people migrate to the
+    new error handler that's planned for the next libpng release, and changed
+    example.c, pngtest.c, and contrib programs to use this macro.
+  Revised some of the DLL-export macros in pngconf.h (Greg Roelofs)
+  Fixed a bug in png_read_png() that caused it to fail to expand some images
+    that it should have expanded.
+  Fixed some mistakes in the unused and undocumented INCH_CONVERSIONS functions
+    in pngget.c
+  Changed the allocation of palette, history, and trans arrays back to
+    the version 1.0.5 method (linking instead of copying) which restores
+    backward compatibility with version 1.0.5.  Added some remarks about
+    that in example.c.  Added "free_me" member to info_ptr and png_ptr
+    and added png_free_data() function.
+  Updated makefile.linux and makefile.gccmmx to make directories conditionally.
+  Made cosmetic changes to pngasmrd.h
+  Added png_set_rows() and png_get_rows(), for use with png_read|write_png().
+  Modified png_read_png() to allocate info_ptr->row_pointers only if it
+    hasn't already been allocated.
+version 1.0.5t [March 4, 2000]
+  Changed png_jmp_env() migration aiding macro to png_jmpbuf().
+  Fixed "interlace" typo (should be "interlaced") in contrib/gregbook/read2-x.c
+  Fixed bug with use of PNG_BEFORE_IHDR bit in png_ptr->mode, introduced when
+    PNG_FLAG_HAVE_CHUNK_HEADER was moved into png_ptr->mode in version 1.0.5b
+  Files in contrib/gregbook were revised to use png_jmpbuf() and to select
+    a 24-bit visual if one is available, and to allow abbreviated options.
+  Files in contrib/pngminus were revised to use the png_jmpbuf() macro.
+  Removed spaces in makefile.linux and makefile.gcmmx, introduced in 1.0.5s
+version 1.0.5u [March 5, 2000]
+  Simplified the code that detects old png.h in png.c and pngtest.c
+  Renamed png_spalette (_p, _pp) to png_sPLT_t (_tp, _tpp)
+  Increased precision of rgb_to_gray calculations from 8 to 15 bits and
+    added png_set_rgb_to_gray_fixed() function.
+  Added makefile.bc32 (32-bit Borland C++, C mode)
+version 1.0.5v [March 11, 2000]
+  Added some parentheses to the png_jmpbuf macro definition.
+  Updated references to the zlib home page, which has moved to freesoftware.com.
+  Corrected bugs in documentation regarding png_read_row() and png_write_row().
+  Updated documentation of png_rgb_to_gray calculations in libpng.3/libpng.txt.
+  Renamed makefile.borland,turboc3 back to makefile.bor,tc3 as in version 1.0.3,
+    revised borland makefiles; added makefile.ibmvac3 and makefile.gcc (Cosmin)
+
+version 1.0.6 [March 20, 2000]
+  Minor revisions of makefile.bor, libpng.txt, and gregbook/rpng2-win.c
+  Added makefile.sggcc (SGI IRIX with gcc)
+version 1.0.6d [April 7, 2000]
+  Changed sprintf() to strcpy() in png_write_sCAL_s() to work without STDIO
+  Added data_length parameter to png_decompress_chunk() function
+  Revised documentation to remove reference to abandoned png_free_chnk functions
+  Fixed an error in png_rgb_to_gray_fixed()
+  Revised example.c, usage of png_destroy_write_struct().
+  Renamed makefile.ibmvac3 to makefile.ibmc, added libpng.icc IBM project file
+  Added a check for info_ptr->free_me&PNG_FREE_TEXT when freeing text in png.c
+  Simplify png_sig_bytes() function to remove use of non-ISO-C strdup().
+version 1.0.6e [April 9, 2000]
+  Added png_data_freer() function.
+  In the code that checks for over-length tRNS chunks, added check of
+    info_ptr->num_trans as well as png_ptr->num_trans (Matthias Benckmann)
+  Minor revisions of libpng.txt/libpng.3.
+  Check for existing data and free it if the free_me flag is set, in png_set_*()
+    and png_handle_*().
+  Only define PNG_WEIGHTED_FILTERS_SUPPORTED when PNG_FLOATING_POINT_SUPPORTED
+    is defined.
+  Changed several instances of PNG_NO_CONSOLE_ID to PNG_NO_STDIO in pngrutil.c
+    and mentioned the purposes of the two macros in libpng.txt/libpng.3.
+version 1.0.6f [April 14, 2000]
+  Revised png_set_iCCP() and png_set_rows() to avoid prematurely freeing data.
+  Add checks in png_set_text() for NULL members of the input text structure.
+  Revised libpng.txt/libpng.3.
+  Removed superfluous prototype for png_set_itxt from png.h
+  Removed "else" from pngread.c, after png_error(), and changed "0" to "length".
+  Changed several png_errors about malformed ancillary chunks to png_warnings.
+version 1.0.6g [April 24, 2000]
+  Added png_pass-* arrays to pnggccrd.c when PNG_USE_LOCAL_ARRAYS is defined.
+  Relocated paragraph about png_set_background() in libpng.3/libpng.txt
+    and other revisions (Matthias Benckmann)
+  Relocated info_ptr->free_me, png_ptr->free_me, and other info_ptr and
+    png_ptr members to restore binary compatibility with libpng-1.0.5
+    (breaks compatibility with libpng-1.0.6).
+version 1.0.6h [April 24, 2000]
+  Changed shared library so-number pattern from 2.x.y.z to xy.z (this builds
+    libpng.so.10 & libpng.so.10.6h instead of libpng.so.2 & libpng.so.2.1.0.6h)
+    This is a temporary change for test purposes.
+version 1.0.6i [May 2, 2000]
+  Rearranged some members at the end of png_info and png_struct, to put
+    unknown_chunks_num and free_me within the original size of the png_structs
+    and free_me, png_read_user_fn, and png_free_fn within the original png_info,
+    because some old applications allocate the structs directly instead of
+    using png_create_*().
+  Added documentation of user memory functions in libpng.txt/libpng.3
+  Modified png_read_png so that it will use user_allocated row_pointers
+    if present, unless free_me directs that it be freed, and added description
+    of the use of png_set_rows() and png_get_rows() in libpng.txt/libpng.3.
+  Added PNG_LEGACY_SUPPORTED macro, and #ifdef out all new (since version
+    1.00) members of png_struct and png_info, to regain binary compatibility
+    when you define this macro.  Capabilities lost in this event
+    are user transforms (new in version 1.0.0),the user transform pointer
+    (new in version 1.0.2), rgb_to_gray (new in 1.0.5), iCCP, sCAL, sPLT,
+    the high-level interface, and unknown chunks support (all new in 1.0.6).
+    This was necessary because of old applications that allocate the structs
+    directly as authors were instructed to do in libpng-0.88 and earlier,
+    instead of using png_create_*().
+  Added modes PNG_CREATED_READ_STRUCT and PNG_CREATED_WRITE_STRUCT which
+    can be used to detect codes that directly allocate the structs, and
+    code to check these modes in png_read_init() and png_write_init() and
+    generate a libpng error if the modes aren't set and PNG_LEGACY_SUPPORTED
+    was not defined.
+  Added makefile.intel and updated makefile.watcom (Pawel Mrochen)
+version 1.0.6j [May 3, 2000]
+  Overloaded png_read_init() and png_write_init() with macros that convert
+    calls to png_read_init_2() or png_write_init_2() that check the version
+    and structure sizes.
+version 1.0.7beta11 [May 7, 2000]
+  Removed the new PNG_CREATED_READ_STRUCT and PNG_CREATED_WRITE_STRUCT modes
+    which are no longer used.
+  Eliminated the three new members of png_text when PNG_LEGACY_SUPPORTED is
+    defined or when neither PNG_READ_iTXt_SUPPORTED nor PNG_WRITE_iTXT_SUPPORTED
+    is defined.
+  Made PNG_NO_READ|WRITE_iTXt the default setting, to avoid memory
+    overrun when old applications fill the info_ptr->text structure directly.
+  Added PNGAPI macro, and added it to the definitions of all exported functions.
+  Relocated version macro definitions ahead of the includes of zlib.h and
+    pngconf.h in png.h.
+version 1.0.7beta12 [May 12, 2000]
+  Revised pngset.c to avoid a problem with expanding the png_debug macro.
+  Deleted some extraneous defines from pngconf.h
+  Made PNG_NO_CONSOLE_IO the default condition when PNG_BUILD_DLL is defined.
+  Use MSC _RPTn debugging instead of fprintf if _MSC_VER is defined.
+  Added png_access_version_number() function.
+  Check for mask&PNG_FREE_CHNK (for TEXT, SCAL, PCAL) in png_free_data().
+  Expanded libpng.3/libpng.txt information about png_data_freer().
+version 1.0.7beta14 [May 17, 2000] (beta13 was not published)
+  Changed pnggccrd.c and pngvcrd.c to handle bad adaptive filter types as
+    warnings instead of errors, as pngrutil.c does.
+  Set the PNG_INFO_IDAT valid flag in png_set_rows() so png_write_png()
+    will actually write IDATs.
+  Made the default PNG_USE_LOCAL_ARRAYS depend on PNG_DLL instead of WIN32.
+  Make png_free_data() ignore its final parameter except when freeing data
+    that can have multiple instances (text, sPLT, unknowns).
+  Fixed a new bug in png_set_rows().
+  Removed info_ptr->valid tests from png_free_data(), as in version 1.0.5.
+  Added png_set_invalid() function.
+  Fixed incorrect illustrations of png_destroy_write_struct() in example.c.
+version 1.0.7beta15 [May 30, 2000]
+  Revised the deliberately erroneous Linux setjmp code in pngconf.h to produce
+    fewer error messages.
+  Rearranged checks for Z_OK to check the most likely path first in pngpread.c
+    and pngwutil.c.
+  Added checks in pngtest.c for png_create_*() returning NULL, and mentioned
+    in libpng.txt/libpng.3 the need for applications to check this.
+  Changed names of png_default_*() functions in pngtest to pngtest_*().
+  Changed return type of png_get_x|y_offset_*() from png_uint_32 to png_int_32.
+  Fixed some bugs in the unused PNG_INCH_CONVERSIONS functions in pngget.c
+  Set each pointer to NULL after freeing it in png_free_data().
+  Worked around a problem in pngconf.h; AIX's strings.h defines an "index"
+    macro that conflicts with libpng's png_color_16.index. (Dimitri Papadapoulos)
+  Added "msvc" directory with MSVC++ project files (Simon-Pierre Cadieux).
+version 1.0.7beta16 [June 4, 2000]
+  Revised the workaround of AIX string.h "index" bug.
+  Added a check for overlength PLTE chunk in pngrutil.c.
+  Added PNG_NO_POINTER_INDEXING macro to use array-indexing instead of pointer
+    indexing in pngrutil.c and pngwutil.c to accommodate a buggy compiler.
+  Added a warning in png_decompress_chunk() when it runs out of data, e.g.
+    when it tries to read an erroneous PhotoShop iCCP chunk.
+  Added PNG_USE_DLL macro.
+  Revised the copyright/disclaimer/license notice.
+  Added contrib/msvctest directory
+version 1.0.7rc1 [June 9, 2000]
+  Corrected the definition of PNG_TRANSFORM_INVERT_ALPHA  (0x0400 not 0x0200)
+  Added contrib/visupng directory (Willem van Schaik)
+version 1.0.7beta18 [June 23, 2000]
+  Revised PNGAPI definition, and pngvcrd.c to work with __GCC__
+    and do not redefine PNGAPI if it is passed in via a compiler directive.
+  Revised visupng/PngFile.c to remove returns from within the Try block.
+  Removed leading underscores from "_PNG_H" and "_PNG_SAVE_BSD_SOURCE" macros.
+  Updated contrib/visupng/cexcept.h to version 1.0.0.
+  Fixed bugs in pngwrite.c and pngwutil.c that prevented writing iCCP chunks.
+version 1.0.7rc2 [June 28, 2000]
+  Updated license to include disclaimers required by UCITA.
+  Fixed "DJBPP" typo in pnggccrd.c introduced in beta18.
+
+version 1.0.7 [July 1, 2000]
+  Revised the definition of "trans_values" in libpng.3/libpng.txt
+version 1.0.8beta1 [July 8, 2000]
+  Added png_free(png_ptr, key) two places in pngpread.c to stop memory leaks.
+  Changed PNG_NO_STDIO to PNG_NO_CONSOLE_IO, several places in pngrutil.c and
+     pngwutil.c.
+  Changed PNG_EXPORT_VAR to use PNG_IMPEXP, in pngconf.h.
+  Removed unused "#include <assert.h>" from png.c
+  Added WindowsCE support.
+  Revised pnggccrd.c to work with gcc-2.95.2 and in the Cygwin environment.
+version 1.0.8beta2 [July 10, 2000]
+  Added project files to the wince directory and made further revisions
+     of pngtest.c, pngrio.c, and pngwio.c in support of WindowsCE.
+version 1.0.8beta3 [July 11, 2000]
+  Only set the PNG_FLAG_FREE_TRNS or PNG_FREE_TRNS flag in png_handle_tRNS()
+     for indexed-color input files to avoid potential double-freeing trans array
+     under some unusual conditions; problem was introduced in version 1.0.6f.
+  Further revisions to pngtest.c and files in the wince subdirectory.
+version 1.0.8beta4 [July 14, 2000]
+  Added the files pngbar.png and pngbar.jpg to the distribution.
+  Added makefile.cygwin, and cygwin support in pngconf.h
+  Added PNG_NO_ZALLOC_ZERO macro (makes png_zalloc skip zeroing memory)
+version 1.0.8rc1 [July 16, 2000]
+  Revised png_debug() macros and statements to eliminate compiler warnings.
+
+version 1.0.8 [July 24, 2000]
+  Added png_flush() in pngwrite.c, after png_write_IEND().
+  Updated makefile.hpux to build a shared library.
+version 1.0.9beta1 [November 10, 2000]
+  Fixed typo in scripts/makefile.hpux
+  Updated makevms.com in scripts and contrib/* and contrib/* (Martin Zinser)
+  Fixed seqence-point bug in contrib/pngminus/png2pnm (Martin Zinser)
+  Changed "cdrom.com" in documentation to "libpng.org"
+  Revised pnggccrd.c to get it all working, and updated makefile.gcmmx (Greg).
+  Changed type of "params" from voidp to png_voidp in png_read|write_png().
+  Make sure PNGAPI and PNG_IMPEXP are defined in pngconf.h.
+  Revised the 3 instances of WRITEFILE in pngtest.c.
+  Relocated "msvc" and "wince" project subdirectories into "dll" subdirectory.
+  Updated png.rc in dll/msvc project
+  Revised makefile.dec to define and use LIBPATH and INCPATH
+  Increased size of global png_libpng_ver[] array from 12 to 18 chars.
+  Made global png_libpng_ver[], png_sig[] and png_pass_*[] arrays const.
+  Removed duplicate png_crc_finish() from png_handle_bKGD() function.
+  Added a warning when application calls png_read_update_info() multiple times.
+  Revised makefile.cygwin
+  Fixed bugs in iCCP support in pngrutil.c and pngwutil.c.
+  Replaced png_set_empty_plte_permitted() with png_permit_mng_features().
+version 1.0.9beta2 [November 19, 2000]
+  Renamed the "dll" subdirectory "projects".
+  Added borland project files to "projects" subdirectory.
+  Set VS_FF_PRERELEASE and VS_FF_PATCHED flags in msvc/png.rc when appropriate.
+  Add error message in png_set_compression_buffer_size() when malloc fails.
+version 1.0.9beta3 [November 23, 2000]
+  Revised PNG_LIBPNG_BUILD_TYPE macro in png.h, used in the msvc project.
+  Removed the png_flush() in pngwrite.c that crashes some applications
+    that don't set png_output_flush_fn.
+  Added makefile.macosx and makefile.aix to scripts directory.
+version 1.0.9beta4 [December 1, 2000]
+  Change png_chunk_warning to png_warning in png_check_keyword().
+  Increased the first part of msg buffer from 16 to 18 in png_chunk_error().
+version 1.0.9beta5 [December 15, 2000]
+  Added support for filter method 64 (for PNG datastreams embedded in MNG).
+version 1.0.9beta6 [December 18, 2000]
+  Revised png_set_filter() to accept filter method 64 when appropriate.
+  Added new PNG_HAVE_PNG_SIGNATURE bit to png_ptr->mode and use it to
+    help prevent applications from using MNG features in PNG datastreams.
+  Added png_permit_mng_features() function.
+  Revised libpng.3/libpng.txt.  Changed "filter type" to "filter method".
+version 1.0.9rc1 [December 23, 2000]
+  Revised test for PNG_HAVE_PNG_SIGNATURE in pngrutil.c
+  Fixed error handling of unknown compression type in png_decompress_chunk().
+  In pngconf.h, define __cdecl when _MSC_VER is defined.
+version 1.0.9beta7 [December 28, 2000]
+  Changed PNG_TEXT_COMPRESSION_zTXt to PNG_COMPRESSION_TYPE_BASE several places.
+  Revised memory management in png_set_hIST and png_handle_hIST in a backward
+    compatible manner.  PLTE and tRNS were revised similarly.
+  Revised the iCCP chunk reader to ignore trailing garbage.
+version 1.0.9beta8 [January 12, 2001]
+  Moved pngasmrd.h into pngconf.h.
+  Improved handling of out-of-spec garbage iCCP chunks generated by PhotoShop.
+version 1.0.9beta9 [January 15, 2001]
+  Added png_set_invalid, png_permit_mng_features, and png_mmx_supported to
+    wince and msvc project module definition files.
+  Minor revision of makefile.cygwin.
+  Fixed bug with progressive reading of narrow interlaced images in pngpread.c
+version 1.0.9beta10 [January 16, 2001]
+  Do not typedef png_FILE_p in pngconf.h when PNG_NO_STDIO is defined.
+  Fixed "png_mmx_supported" typo in project definition files.
+version 1.0.9beta11 [January 19, 2001]
+  Updated makefile.sgi to make shared library.
+  Removed png_mmx_support() function and disabled PNG_MNG_FEATURES_SUPPORTED
+    by default, for the benefit of DLL forward compatibility.  These will
+    be re-enabled in version 1.2.0.
+version 1.0.9rc2 [January 22, 2001]
+  Revised cygwin support.
+
+version 1.0.9 [January 31, 2001]
+  Added check of cygwin's ALL_STATIC in pngconf.h
+  Added "-nommx" parameter to contrib/gregbook/rpng2-win and rpng2-x demos.
+version 1.0.10beta1 [March 14, 2001]
+  Revised makefile.dec, makefile.sgi, and makefile.sggcc; added makefile.hpgcc.
+  Reformatted libpng.3 to eliminate bad line breaks.
+  Added checks for _mmx_supported in the read_filter_row function of pnggccrd.c
+  Added prototype for png_mmx_support() near the top of pnggccrd.c
+  Moved some error checking from png_handle_IHDR to png_set_IHDR.
+  Added PNG_NO_READ_SUPPORTED and PNG_NO_WRITE_SUPPORTED macros.
+  Revised png_mmx_support() function in pnggccrd.c
+  Restored version 1.0.8 PNG_WRITE_EMPTY_PLTE_SUPPORTED behavior in pngwutil.c
+  Fixed memory leak in contrib/visupng/PngFile.c
+  Fixed bugs in png_combine_row() in pnggccrd.c and pngvcrd.c (C version)
+  Added warnings when retrieving or setting gamma=0.
+  Increased the first part of msg buffer from 16 to 18 in png_chunk_warning().
+version 1.0.10rc1 [March 23, 2001]
+  Changed all instances of memcpy, strcpy, and strlen to png_memcpy, png_strcpy,
+    and png_strlen.
+  Revised png_mmx_supported() function in pnggccrd.c to return proper value.
+  Fixed bug in progressive reading (pngpread.c) with small images (height < 8).
+
+version 1.0.10 [March 30, 2001]
+  Deleted extraneous space (introduced in 1.0.9) from line 42 of makefile.cygwin
+  Added beos project files (Chris Herborth)
+version 1.0.11beta1 [April 3, 2001]
+  Added type casts on several png_malloc() calls (Dimitri Papadapoulos).
+  Removed a no-longer needed AIX work-around from pngconf.h
+  Changed several "//" single-line comments to C-style in pnggccrd.c
+version 1.0.11beta2 [April 11, 2001]
+  Removed PNGAPI from several functions whose prototypes did not have PNGAPI.
+  Updated scripts/pngos2.def
+version 1.0.11beta3 [April 14, 2001]
+  Added checking the results of many instances of png_malloc() for NULL
+version 1.0.11beta4 [April 20, 2001]
+  Undid the changes from version 1.0.11beta3.  Added a check for NULL return
+    from user's malloc_fn().
+  Removed some useless type casts of the NULL pointer.
+  Added makefile.netbsd
+
+version 1.0.11 [April 27, 2001]
+  Revised makefile.netbsd
+version 1.0.12beta1 [May 14, 2001]
+  Test for Windows platform in pngconf.h when including malloc.h (Emmanuel Blot)
+  Updated makefile.cygwin and handling of Cygwin's ALL_STATIC in pngconf.h
+  Added some never-to-be-executed code in pnggccrd.c to quiet compiler warnings.
+  Eliminated the png_error about apps using png_read|write_init().  Instead,
+    libpng will reallocate the png_struct and info_struct if they are too small.
+    This retains future binary compatibility for old applications written for
+    libpng-0.88 and earlier.
+version 1.2.0beta1 [May 6, 2001]
+  Bumped DLLNUM to 2.
+  Re-enabled PNG_MNG_FEATURES_SUPPORTED and enabled PNG_ASSEMBLER_CODE_SUPPORTED
+    by default.
+  Added runtime selection of MMX features.
+  Added png_set_strip_error_numbers function and related macros.
+version 1.2.0beta2 [May 7, 2001]
+  Finished merging 1.2.0beta1 with version 1.0.11
+  Added a check for attempts to read or write PLTE in grayscale PNG datastreams.
+version 1.2.0beta3 [May 17, 2001]
+  Enabled user memory function by default.
+  Modified png_create_struct so it passes user mem_ptr to user memory allocator.
+  Increased png_mng_features flag from png_byte to png_uint_32.
+  Bumped shared-library (so-number) and dll-number to 3.
+version 1.2.0beta4 [June 23, 2001]
+  Check for missing profile length field in iCCP chunk and free chunk_data
+     in case of truncated iCCP chunk.
+  Bumped shared-library number to 3 in makefile.sgi and makefile.sggcc
+  Bumped dll-number from 2 to 3 in makefile.cygwin
+  Revised contrib/gregbook/rpng*-x.c to avoid a memory leak and to exit cleanly
+     if user attempts to run it on an 8-bit display.
+  Updated contrib/gregbook
+  Use png_malloc instead of png_zalloc to allocate palette in pngset.c
+  Updated makefile.ibmc
+  Added some typecasts to eliminate gcc 3.0 warnings.  Changed prototypes
+     of png_write_oFFS width and height from png_uint_32 to png_int_32.
+  Updated example.c
+  Revised prototypes for png_debug_malloc and png_debug_free in pngtest.c
+version 1.2.0beta5 [August 8, 2001]
+  Revised contrib/gregbook
+  Revised makefile.gcmmx
+  Revised pnggccrd.c to conditionally compile some thread-unsafe code only
+     when PNG_THREAD_UNSAFE_OK is defined.
+  Added tests to prevent pngwutil.c from writing a bKGD or tRNS chunk with
+     value exceeding 2^bit_depth-1
+  Revised makefile.sgi and makefile.sggcc
+  Replaced calls to fprintf(stderr,...) with png_warning() in pnggccrd.c
+  Removed restriction that do_invert_mono only operate on 1-bit opaque files
+
+version 1.2.0 [September 1, 2001]
+  Changed a png_warning() to png_debug() in pnggccrd.c
+  Fixed contrib/gregbook/rpng-x.c, rpng2-x.c to avoid crash with XFreeGC().
+version 1.2.1beta1 [October 19, 2001]
+  Revised makefile.std in contrib/pngminus
+  Include background_1 in png_struct regardless of gamma support.
+  Revised makefile.netbsd and makefile.macosx, added makefile.darwin.
+  Revised example.c to provide more details about using row_callback().
+version 1.2.1beta2 [October 25, 2001]
+  Added type cast to each NULL appearing in a function call, except for
+    WINCE functions.
+  Added makefile.so9.
+version 1.2.1beta3 [October 27, 2001]
+  Removed type casts from all NULLs.
+  Simplified png_create_struct_2().
+version 1.2.1beta4 [November 7, 2001]
+  Revised png_create_info_struct() and png_creat_struct_2().
+  Added error message if png_write_info() was omitted.
+  Type cast NULLs appearing in function calls when _NO_PROTO or
+    PNG_TYPECAST_NULL is defined.
+version 1.2.1rc1 [November 24, 2001]
+  Type cast NULLs appearing in function calls except when PNG_NO_TYPECAST_NULL
+    is defined.
+  Changed typecast of "size" argument to png_size_t in pngmem.c calls to
+    the user malloc_fn, to agree with the prototype in png.h
+  Added a pop/push operation to pnggccrd.c, to preserve Eflag (Maxim Sobolev)
+  Updated makefile.sgi to recognize LIBPATH and INCPATH.
+  Updated various makefiles so "make clean" does not remove previous major
+    version of the shared library.
+version 1.2.1rc2 [December 4, 2001]
+  Always allocate 256-entry internal palette, hist, and trans arrays, to
+    avoid out-of-bounds memory reference caused by invalid PNG datastreams.
+  Added a check for prefix_length > data_length in iCCP chunk handler.
+
+version 1.2.1 [December 7, 2001]
+  None.
+version 1.2.2beta1 [February 22, 2002]
+  Fixed a bug with reading the length of iCCP profiles (Larry Reeves).
+  Revised makefile.linux, makefile.gcmmx, and makefile.sgi to generate
+    libpng.a, libpng12.so (not libpng.so.3), and libpng12/png.h
+  Revised makefile.darwin to remove "-undefined suppress" option.
+  Added checks for gamma and chromaticity values over 21474.83, which exceed
+    the limit for PNG unsigned 32-bit integers when encoded.
+  Revised calls to png_create_read_struct() and png_create_write_struct()
+    for simpler debugging.
+  Revised png_zalloc() so zlib handles errors (uses PNG_FLAG_MALLOC_NULL_MEM_OK)
+version 1.2.2beta2 [February 23, 2002]
+  Check chunk_length and idat_size for invalid (over PNG_MAX_UINT) lengths.
+  Check for invalid image dimensions in png_get_IHDR.
+  Added missing "fi;" in the install target of the SGI makefiles.
+  Added install-static to all makefiles that make shared libraries.
+  Always do gamma compensation when image is partially transparent.
+version 1.2.2beta3 [March 7, 2002]
+  Compute background.gray and background_1.gray even when color_type is RGB
+    in case image gets reduced to gray later.
+  Modified shared-library makefiles to install pkgconfig/libpngNN.pc.
+  Export (with PNGAPI) png_zalloc, png_zfree, and png_handle_as_unknown
+  Removed unused png_write_destroy_info prototype from png.h
+  Eliminated incorrect use of width_mmx from pnggccrd.c in pixel_bytes == 8 case
+  Added install-shared target to all makefiles that make shared libraries.
+  Stopped a double free of palette, hist, and trans when not using free_me.
+  Added makefile.32sunu for Sun Ultra 32 and makefile.64sunu for Sun Ultra 64.
+version 1.2.2beta4 [March 8, 2002]
+  Compute background.gray and background_1.gray even when color_type is RGB
+    in case image gets reduced to gray later (Jason Summers).
+  Relocated a misplaced /bin/rm in the "install-shared" makefile targets
+  Added PNG_1_0_X macro which can be used to build a 1.0.x-compatible library.
+version 1.2.2beta5 [March 26, 2002]
+  Added missing PNGAPI to several function definitions.
+  Check for invalid bit_depth or color_type in png_get_IHDR(), and
+    check for missing PLTE or IHDR in png_push_read_chunk() (Matthias Clasen).
+  Revised iTXt support to accept NULL for lang and lang_key.
+  Compute gamma for color components of background even when color_type is gray.
+  Changed "()" to "{}" in scripts/libpng.pc.in.
+  Revised makefiles to put png.h and pngconf.h only in $prefix/include/libpngNN
+  Revised makefiles to make symlink to libpng.so.NN in addition to libpngNN.so
+version 1.2.2beta6 [March 31, 2002]
+version 1.0.13beta1 [March 31, 2002]
+  Prevent png_zalloc() from trying to memset memory that it failed to acquire.
+  Add typecasts of PNG_MAX_UINT in pngset_cHRM_fixed() (Matt Holgate).
+  Ensure that the right function (user or default) is used to free the
+    png_struct after an error in png_create_read_struct_2().
+version 1.2.2rc1 [April 7, 2002]
+version 1.0.13rc1 [April 7, 2002]
+  Save the ebx register in pnggccrd.c (Sami Farin)
+  Add "mem_ptr = png_ptr->mem_ptr" in png_destroy_write_struct() (Paul Gardner).
+  Updated makefiles to put headers in include/libpng and remove old include/*.h.
+
+version 1.2.2 [April 15, 2002]
+version 1.0.13 [April 15, 2002]
+  Revised description of png_set_filter() in libpng.3/libpng.txt.
+  Revised makefile.netbsd and added makefile.neNNbsd and makefile.freebsd
+version 1.0.13patch01 [April 17, 2002]
+version 1.2.2patch01 [April 17, 2002]
+  Changed ${PNGMAJ}.${PNGVER} bug to ${PNGVER} in makefile.sgi and makefile.sggcc
+  Fixed VER -> PNGVER typo in makefile.macosx and added install-static to install
+  Added install: target to makefile.32sunu and makefile.64sunu
+version 1.0.13patch03 [April 18, 2002]
+version 1.2.2patch03 [April 18, 2002]
+  Revised 15 makefiles to link libpng.a to libpngNN.a and the include libpng
+  subdirectory to libpngNN subdirectory without the full pathname.
+  Moved generation of libpng.pc from "install" to "all" in 15 makefiles.
+version 1.2.3rc1 [April 28, 2002]
+  Added install-man target to 15 makefiles (Dimitri Papadopolous-Orfanos).
+  Added $(DESTDIR) feature to 24 makefiles (Tim Mooney)
+  Fixed bug with $prefix, should be $(prefix) in makefile.hpux.
+  Updated cygwin-specific portion of pngconf.h and revised makefile.cygwin
+  Added a link from libpngNN.pc to libpng.pc in 15 makefiles.
+  Added links from include/libpngNN/*.h to include/*.h in 24 makefiles.
+  Revised makefile.darwin to make relative links without full pathname.
+  Added setjmp() at the end of png_create_*_struct_2() in case user forgets
+    to put one in their application.
+  Restored png_zalloc() and png_zfree() prototypes to version 1.2.1 and
+    removed them from module definition files.
+version 1.2.3rc2 [May 1, 2002]
+  Fixed bug in reporting number of channels in pngget.c and pngset.c,
+    that was introduced in version 1.2.2beta5.
+  Exported png_zalloc(), png_zfree(), png_default_read(), png_default_write(),
+    png_default_flush(), and png_push_fill_buffer() and included them in
+    module definition files.
+  Added "libpng.pc" dependency to the "install-shared" target in 15 makefiles.
+version 1.2.3rc3 [May 1, 2002]
+  Revised prototype for png_default_flush()
+  Remove old libpng.pc and libpngNN.pc before installing new ones.
+version 1.2.3rc4 [May 2, 2002]
+  Typos in *.def files (png_default_read|write -> png_default_read|write_data)
+  In makefiles, changed rm libpng.NN.pc to rm libpngNN.pc
+  Added libpng-config and libpngNN-config and modified makefiles to install them.
+  Changed $(MANPATH) to $(DESTDIR)$(MANPATH) in makefiles
+  Added "Win32 DLL VB" configuration to projects/msvc/libpng.dsp
+version 1.2.3rc5 [May 11, 2002]
+  Changed "error" and "message" in prototypes to "error_message" and
+    "warning_message" to avoid namespace conflict.
+  Revised 15 makefiles to build libpng-config from libpng-config-*.in
+  Once more restored png_zalloc and png_zfree to regular nonexported form.
+  Restored png_default_read|write_data, png_default_flush, png_read_fill_buffer
+    to nonexported form, but with PNGAPI, and removed them from module def files.
+version 1.2.3rc6 [May 14, 2002]
+  Removed "PNGAPI" from png_zalloc() and png_zfree() in png.c
+  Changed "Gz" to "Gd" in projects/msvc/libpng.dsp and zlib.dsp.
+  Removed leftover libpng-config "sed" script from four makefiles.
+  Revised libpng-config creating script in 16 makefiles.
+
+version 1.2.3 [May 22, 2002]
+  Revised libpng-config target in makefile.cygwin.
+  Removed description of png_set_mem_fn() from documentation.
+  Revised makefile.freebsd.
+  Minor cosmetic changes to 15 makefiles, e.g., $(DI) = $(DESTDIR)/$(INCDIR).
+  Revised projects/msvc/README.txt
+  Changed -lpng to -lpngNN in LDFLAGS in several makefiles.
+version 1.2.4beta1 [May 24, 2002]
+  Added libpng.pc and libpng-config to "all:" target in 16 makefiles.
+  Fixed bug in 16 makefiles: $(DESTDIR)/$(LIBPATH) to $(DESTDIR)$(LIBPATH)
+  Added missing "\" before closing double quote in makefile.gcmmx.
+  Plugged various memory leaks; added png_malloc_warn() and png_set_text_2()
+    functions.
+version 1.2.4beta2 [June 25, 2002]
+  Plugged memory leak of png_ptr->current_text (Matt Holgate).
+  Check for buffer overflow before reading CRC in pngpread.c (Warwick Allison)
+  Added -soname to the loader flags in makefile.dec, makefile.sgi, and
+    makefile.sggcc.
+  Added "test-installed" target to makefile.linux, makefile.gcmmx,
+    makefile.sgi, and makefile.sggcc.
+version 1.2.4beta3 [June 28, 2002]
+  Plugged memory leak of row_buf in pngtest.c when there is a png_error().
+  Detect buffer overflow in pngpread.c when IDAT is corrupted with extra data.
+  Added "test-installed" target to makefile.32sunu, makefile.64sunu,
+    makefile.beos, makefile.darwin, makefile.dec, makefile.macosx, 
+    makefile.solaris, makefile.hpux, makefile.hpgcc, and makefile.so9.
+version 1.2.4rc1 and 1.0.14rc1 [July 2, 2002]
+  Added "test-installed" target to makefile.cygwin and makefile.sco.
+  Revised pnggccrd.c to be able to back out version 1.0.x via PNG_1_0_X macro.
+
+version 1.2.4 and 1.0.14 [July 8, 2002]
+  Changed png_warning() to png_error() when width is too large to process.
+version 1.2.4patch01 [July 20, 2002]
+  Revised makefile.cygwin to use DLL number 12 instead of 13.
+version 1.2.5beta1 [August 6, 2002]
+  Added code to contrib/gregbook/readpng2.c to ignore unused chunks.
+  Replaced toucan.png in contrib/gregbook (it has been corrupt since 1.0.11)
+  Removed some stray *.o files from contrib/gregbook.
+  Changed png_error() to png_warning() about "Too much data" in pngpread.c
+    and about "Extra compressed data" in pngrutil.c.
+  Prevent png_ptr->pass from exceeding 7 in png_push_finish_row().
+  Updated makefile.hpgcc
+  Updated png.c and pnggccrd.c handling of return from png_mmx_support()
+version 1.2.5beta2 [August 15, 2002]
+  Only issue png_warning() about "Too much data" in pngpread.c when avail_in
+    is nonzero.
+  Updated makefiles to install a separate libpng.so.3 with its own rpath.
+version 1.2.5rc1 and 1.0.15rc1 [August 24, 2002]
+  Revised makefiles to not remove previous minor versions of shared libraries.
+version 1.2.5rc2 and 1.0.15rc2 [September 16, 2002]
+  Revised 13 makefiles to remove "-lz" and "-L$(ZLIBLIB)", etc., from shared
+    library loader directive.
+  Added missing "$OBJSDLL" line to makefile.gcmmx.
+  Added missing "; fi" to makefile.32sunu.
+version 1.2.5rc3 and 1.0.15rc3 [September 18, 2002]
+  Revised libpng-config script.
+
+version 1.2.5 and 1.0.15 [October 3, 2002]
+  Revised makefile.macosx, makefile.darwin, makefile.hpgcc, and makefile.hpux,
+    and makefile.aix.
+  Relocated two misplaced PNGAPI lines in pngtest.c
+version 1.2.6beta1 [October 22, 2002]
+  Commented out warning about uninitialized mmx_support in pnggccrd.c.
+  Changed "IBMCPP__" flag to "__IBMCPP__" in pngconf.h.
+  Relocated two more misplaced PNGAPI lines in pngtest.c
+  Fixed memory overrun bug in png_do_read_filler() with 16-bit datastreams,
+    introduced in version 1.0.2.
+  Revised makefile.macosx, makefile.dec, makefile.aix, and makefile.32sunu.
+version 1.2.6beta2 [November 1, 2002]
+  Added libpng-config "--ldopts" output.
+  Added "AR=ar" and "ARFLAGS=rc" and changed "ar rc" to "$(AR) $(ARFLAGS)"
+    in makefiles.
+version 1.2.6beta3 [July 18, 2004]
+  Reverted makefile changes from version 1.2.6beta2 and some of the changes
+    from version 1.2.6beta1; these will be postponed until version 1.2.7.
+    Version 1.2.6 is going to be a simple bugfix release.
+  Changed the one instance of "ln -sf" to "ln -f -s" in each Sun makefile.
+  Fixed potential overrun in pngerror.c by using strncpy instead of memcpy.
+  Added "#!/bin/sh" at the top of configure, for recognition of the
+    'x' flag under Cygwin (Cosmin).
+  Optimized vacuous tests that silence compiler warnings, in png.c (Cosmin).
+  Added support for PNG_USER_CONFIG, in pngconf.h (Cosmin).
+  Fixed the special memory handler for Borland C under DOS, in pngmem.c
+    (Cosmin).
+  Removed some spurious assignments in pngrutil.c (Cosmin).
+  Replaced 65536 with 65536L, and 0xffff with 0xffffL, to silence warnings
+    on 16-bit platforms (Cosmin).
+  Enclosed shift op expressions in parentheses, to silence warnings (Cosmin).
+  Used proper type png_fixed_point, to avoid problems on 16-bit platforms,
+    in png_handle_sRGB() (Cosmin).
+  Added compression_type to png_struct, and optimized the window size
+    inside the deflate stream (Cosmin).
+  Fixed definition of isnonalpha(), in pngerror.c and pngrutil.c (Cosmin).
+  Fixed handling of unknown chunks that come after IDAT (Cosmin).
+  Allowed png_error() and png_warning() to work even if png_ptr == NULL
+    (Cosmin).
+  Replaced row_info->rowbytes with row_bytes in png_write_find_filter()
+    (Cosmin).
+  Fixed definition of PNG_LIBPNG_VER_DLLNUM (Simon-Pierre).
+  Used PNG_LIBPNG_VER and PNG_LIBPNG_VER_STRING instead of the hardcoded
+    values in png.c (Simon-Pierre, Cosmin).
+  Initialized png_libpng_ver[] with PNG_LIBPNG_VER_STRING (Simon-Pierre).
+  Replaced PNG_LIBPNG_VER_MAJOR with PNG_LIBPNG_VER_DLLNUM in png.rc
+    (Simon-Pierre).
+  Moved the definition of PNG_HEADER_VERSION_STRING near the definitions
+    of the other PNG_LIBPNG_VER_... symbols in png.h (Cosmin).
+  Relocated #ifndef PNGAPI guards in pngconf.h (Simon-Pierre, Cosmin).
+  Updated scripts/makefile.vc(a)win32 (Cosmin).
+  Updated the MSVC project (Simon-Pierre, Cosmin).
+  Updated the Borland C++ Builder project (Cosmin).
+  Avoided access to asm_flags in pngvcrd.c, if PNG_1_0_X is defined (Cosmin).
+  Commented out warning about uninitialized mmx_support in pngvcrd.c (Cosmin).
+  Removed scripts/makefile.bd32 and scripts/pngdef.pas (Cosmin).
+  Added extra guard around inclusion of Turbo C memory headers, in pngconf.h
+    (Cosmin).
+  Renamed projects/msvc/ to projects/visualc6/, and projects/borland/ to
+    projects/cbuilder5/ (Cosmin).
+  Moved projects/visualc6/png32ms.def to scripts/pngw32.def,
+    and projects/visualc6/png.rc to scripts/pngw32.rc (Cosmin).
+  Added projects/visualc6/pngtest.dsp; removed contrib/msvctest/ (Cosmin).
+  Changed line endings to DOS style in cbuilder5 and visualc6 files, even
+    in the tar.* distributions (Cosmin).
+  Updated contrib/visupng/VisualPng.dsp (Cosmin).
+  Updated contrib/visupng/cexcept.h to version 2.0.0 (Cosmin).
+  Added a separate distribution with "configure" and supporting files (Junichi).
+version 1.2.6beta4 [July 28, 2004]
+  Added user ability to change png_size_t via a PNG_SIZE_T macro.
+  Added png_sizeof() and png_convert_size() functions.
+  Added PNG_SIZE_MAX (maximum value of a png_size_t variable.
+  Added check in png_malloc_default() for (size_t)size != (png_uint_32)size
+    which would indicate an overflow.
+  Changed sPLT failure action from png_error to png_warning and abandon chunk.
+  Changed sCAL and iCCP failures from png_error to png_warning and abandon.
+  Added png_get_uint_31(png_ptr, buf) function.
+  Added PNG_UINT_32_MAX macro.
+  Renamed PNG_MAX_UINT to PNG_UINT_31_MAX.
+  Made png_zalloc() issue a png_warning and return NULL on potential
+    overflow.
+  Turn on PNG_NO_ZALLOC_ZERO by default in version 1.2.x
+  Revised "clobber list" in pnggccrd.c so it will compile under gcc-3.4.
+  Revised Borland portion of png_malloc() to return NULL or issue
+    png_error() according to setting of PNG_FLAG_MALLOC_NULL_MEM_OK.
+  Added PNG_NO_SEQUENTIAL_READ_SUPPORTED macro to conditionally remove
+    sequential read support.
+  Added some "#if PNG_WRITE_SUPPORTED" blocks.
+  #ifdef'ed out some redundancy in png_malloc_default().
+  Use png_malloc instead of png_zalloc to allocate the pallete.
+version 1.0.16rc1 and 1.2.6rc1 [August 4, 2004]
+  Fixed buffer overflow vulnerability in png_handle_tRNS()
+  Fixed integer arithmetic overflow vulnerability in png_read_png().
+  Fixed some harmless bugs in png_handle_sBIT, etc, that would cause
+    duplicate chunk types to go undetected.
+  Fixed some timestamps in the -config version
+  Rearranged order of processing of color types in png_handle_tRNS().
+  Added ROWBYTES macro to calculate rowbytes without integer overflow.
+  Updated makefile.darwin and removed makefile.macosx from scripts directory.
+  Imposed default one million column, one-million row limits on the image
+    dimensions, and added png_set_user_limits() function to override them.
+  Revised use of PNG_SET_USER_LIMITS_SUPPORTED macro.
+  Fixed wrong cast of returns from png_get_user_width|height_max().
+  Changed some "keep the compiler happy" from empty statements to returns,
+  Revised libpng.txt to remove 1.2.x stuff from the 1.0.x distribution
+version 1.0.16rc2 and 1.2.6rc2 [August 7, 2004]
+  Revised makefile.darwin and makefile.solaris.  Removed makefile.macosx.
+  Revised pngtest's png_debug_malloc() to use png_malloc() instead of
+    png_malloc_default() which is not supposed to be exported.
+  Fixed off-by-one error in one of the conversions to PNG_ROWBYTES() in
+    pngpread.c.  Bug was introduced in 1.2.6rc1.
+  Fixed bug in RGB to RGBX transformation introduced in 1.2.6rc1.
+  Fixed old bug in RGB to Gray transformation.
+  Fixed problem with 64-bit compilers by casting arguments to abs()
+    to png_int_32.
+  Changed "ln -sf" to "ln -f -s" in three makefiles (solaris, sco, so9).
+  Changed "HANDLE_CHUNK_*" to "PNG_HANDLE_CHUNK_*" (Cosmin)
+  Added "-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)" to 15 *NIX makefiles.
+  Added code to update the row_info->colortype in png_do_read_filler() (MSB).
+version 1.0.16rc3 and 1.2.6rc3 [August 9, 2004]
+  Eliminated use of "abs()" in testing cHRM and gAMA values, to avoid
+    trouble with some 64-bit compilers.  Created PNG_OUT_OF_RANGE() macro.
+  Revised documentation of png_set_keep_unknown_chunks().
+  Check handle_as_unknown status in pngpread.c, as in pngread.c previously.
+  Moved  "PNG_HANDLE_CHUNK_*" macros out of PNG_INTERNAL section of png.h
+  Added "rim" definitions for CONST4 and CONST6 in pnggccrd.c
+version 1.0.16rc4 and 1.2.6rc4 [August 10, 2004]
+  Fixed mistake in pngtest.c introduced in 1.2.6rc2 (declaration of
+    "pinfo" was out of place).
+version 1.0.16rc5 and 1.2.6rc5 [August 10, 2004]
+  Moved  "PNG_HANDLE_CHUNK_*" macros out of PNG_ASSEMBLER_CODE_SUPPORTED
+     section of png.h where they were inadvertently placed in version rc3.
+
+version 1.0.16 and 1.2.6 [August 15, 2004]
+  Revised pngtest so memory allocation testing is only done when PNG_DEBUG==1.
+version 1.2.7beta1 [August 26, 2004]
+  Removed unused pngasmrd.h file.
+  Removed references to uu.net for archived files.  Added references to
+    PNG Spec (second edition) and the PNG ISO/IEC Standard.
+  Added "test-dd" target in 15 makefiles, to run pngtest in DESTDIR.
+  Fixed bug with "optimized window size" in the IDAT datastream, that
+    causes libpng to write PNG files with incorrect zlib header bytes.
+version 1.2.7beta2 [August 28, 2004]
+  Fixed bug with sCAL chunk and big-endian machines (David Munro).
+  Undid new code added in 1.2.6rc2 to update the color_type in
+    png_set_filler().
+  Added png_set_add_alpha() that updates color type.
+version 1.0.17rc1 and 1.2.7rc1 [September 4, 2004]
+  Revised png_set_strip_filler() to not remove alpha if color_type has alpha.
+version 1.0.17 and 1.2.7 [September 12, 2004]
+  Added makefile.hp64
+  Changed projects/msvc/png32ms.def to scripts/png32ms.def in makefile.cygwin
+version 1.2.8beta1 [November 1, 2004]
+  Fixed bug in png_text_compress() that would fail to complete a large block.
+  Fixed bug, introduced in libpng-1.2.7, that overruns a buffer during
+    strip alpha operation in png_do_strip_filler().
+  Added PNG_1_2_X definition in pngconf.h
+  #ifdef out png_info_init in png.c and png_read_init in pngread.c (as of 1.3.0)
+version 1.2.8beta2 [November 2, 2004]
+  Reduce color_type to a nonalpha type after strip alpha operation in
+    png_do_strip_filler().
+version 1.2.8beta3 [November 3, 2004]
+  Revised definitions of PNG_MAX_UINT_32, PNG_MAX_SIZE, and PNG_MAXSUM
+version 1.2.8beta4 [November 12, 2004]
+  Fixed (again) definition of PNG_LIBPNG_VER_DLLNUM in png.h (Cosmin).
+  Added PNG_LIBPNG_BUILD_PRIVATE in png.h (Cosmin).
+  Set png_ptr->zstream.data_type to Z_BINARY, to avoid unnecessary detection
+    of data type in deflate (Cosmin).
+  Deprecated but continue to support SPECIALBUILD and PRIVATEBUILD in favor of
+    PNG_LIBPNG_BUILD_SPECIAL_STRING and PNG_LIBPNG_BUILD_PRIVATE_STRING.
+version 1.2.8beta5 [November 20, 2004]
+  Use png_ptr->flags instead of png_ptr->transformations to pass
+    PNG_STRIP_ALPHA info to png_do_strip_filler(), to preserve ABI
+    compatibility.
+  Revised handling of SPECIALBUILD, PRIVATEBUILD, 
+    PNG_LIBPNG_BUILD_SPECIAL_STRING and PNG_LIBPNG_BUILD_PRIVATE_STRING.
+version 1.2.8rc1 [November 24, 2004]
+  Moved handling of BUILD macros from pngconf.h to png.h
+  Added definition of PNG_LIBPNG_BASE_TYPE in png.h, inadvertently
+    omitted from beta5.
+  Revised scripts/pngw32.rc
+  Despammed mailing addresses by masking "@" with "at".
+  Inadvertently installed a supposedly faster test version of pngrutil.c
+version 1.2.8rc2 [November 26, 2004]
+  Added two missing "\" in png.h
+  Change tests in pngread.c and pngpread.c to
+    if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
+       png_do_read_transformations(png_ptr);
+version 1.2.8rc3 [November 28, 2004]
+  Reverted pngrutil.c to version libpng-1.2.8beta5.
+  Added scripts/makefile.elf with supporting code in pngconf.h for symbol
+    versioning (John Bowler).
+version 1.2.8rc4 [November 29, 2004]
+  Added projects/visualc7 (Simon-pierre).
+version 1.2.8rc5 [November 29, 2004]
+  Fixed new typo in scripts/pngw32.rc
+version 1.2.8 [December 3, 2004]
+  Removed projects/visualc7, added projects/visualc71.
+
+Send comments/corrections/commendations to
+png-implement at ccrc.wustl.edu (subscription required; write to
+majordomo at ccrc.wustl.edu with "subscribe png-implement" in the message)
+or to glennrp at users.sourceforge.net
+
+Glenn R-P
diff --git a/gs/libpng/INSTALL b/gs/libpng/INSTALL
new file mode 100644
index 000000000..ee3d0209c
--- /dev/null
+++ b/gs/libpng/INSTALL
@@ -0,0 +1,169 @@
+
+Installing libpng version 1.2.8 - December 3, 2004
+
+Before installing libpng, you must first install zlib.  zlib
+can usually be found wherever you got libpng.  zlib can be
+placed in another directory, at the same level as libpng.
+Note that your system might already have a preinstalled
+zlib, but you will still need to have access to the
+zlib.h and zconf.h include files that correspond to the
+version of zlib that's installed.
+
+You can rename the directories that you downloaded (they
+might be called "libpng-1.2.8" or "lpng109" and "zlib-1.2.1"
+or "zlib121") so that you have directories called "zlib" and "libpng".
+
+Your directory structure should look like this:
+
+   ..       (the parent directory)
+      libpng  (this directory)
+          INSTALL (this file)
+          README
+          *.h
+          *.c
+          contrib
+             gregbook
+             pngminus
+             pngsuite
+             visupng
+          projects
+             beos
+             c5builder (Borland)
+             visualc6 (msvc)
+             netware.txt
+             wince.txt
+          scripts
+             makefile.*
+          pngtest.png
+          etc.
+      zlib
+          README
+          *.h
+          *.c
+          contrib
+          etc.
+
+If the line endings in the files look funny, you may wish to get the other
+distribution of libpng.  It is available in both tar.gz (UNIX style line
+endings) and zip (DOS style line endings) formats.
+
+
+If you are building libpng with MSVC, you can enter the
+libpng projects\visualc6 directory and follow the instructions in
+projects\visualc6\README.txt.
+
+You can build libpng for WindowsCE by downloading and installing
+the projects\wince directory as instructed in the projects\wince.txt file, and
+then following the instructions in the README* files.  Similarly, you can
+build libpng for Netware or Beos as instructed in projects\netware.txt
+or projects\beos.
+
+Else enter the zlib directory and follow the instructions in zlib/README,
+then come back here and choose the appropriate makefile.sys in the scripts
+directory.
+
+The files that are presently available in the scripts directory
+include
+
+ makefile.std      =>  Generic UNIX makefile (cc, creates static libpng.a)
+ makefile.elf      =>  Linux/ELF makefile symbol versioning,
+                       gcc, creates libpng12.so.0.1.2.8)
+ makefile.linux    =>  Linux/ELF makefile
+                       (gcc, creates libpng12.so.0.1.2.8)
+ makefile.gcmmx    =>  Linux/ELF makefile
+                       (gcc, creates libpng12.so.0.1.2.8,
+                       uses assembler code tuned for Intel MMX platform)
+ makefile.gcc      =>  Generic makefile (gcc, creates static libpng.a)
+ makefile.knr      =>  Archaic UNIX Makefile that converts files with
+                       ansi2knr (Requires ansi2knr.c from
+                       ftp://ftp.cs.wisc.edu/ghost)
+ makefile.aix      =>  AIX/gcc makefile
+ makefile.cygwin   =>  Cygwin/gcc makefile
+ makefile.darwin   =>  Darwin makefile, can use on MacosX
+ makefile.dec      =>  DEC Alpha UNIX makefile
+ makefile.freebsd  =>  FreeBSD makefile
+ makefile.hpgcc    =>  HPUX makefile using gcc
+ makefile.hpux     =>  HPUX (10.20 and 11.00) makefile
+ makefile.hp64     =>  HPUX (10.20 and 11.00) makefile, 64-bit
+ makefile.ibmc     =>  IBM C/C++ version 3.x for Win32 and OS/2 (static)
+ makefile.intel    =>  Intel C/C++ version 4.0 and later
+ libpng.icc        =>  Project file for IBM VisualAge/C++ version 4.0 or later
+ makefile.netbsd   =>  NetBSD/cc makefile, uses PNGGCCRD, makes libpng.so.
+ makefile.ne12bsd  =>  NetBSD/cc makefile, uses PNGGCCRD,
+                       makes libpng12.so
+ makefile.openbsd  =>  OpenBSD makefile
+ makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib)
+ makefile.sggcc    =>  Silicon Graphics (gcc,
+                       creates libpng12.so.0.1.2.8)
+ makefile.sunos    =>  Sun makefile
+ makefile.solaris  =>  Solaris 2.X makefile (gcc,
+                       creates libpng12.so.0.1.2.8)
+ makefile.so9      =>  Solaris 9 makefile (gcc,
+                       creates libpng12.so.0.1.2.8)
+ makefile.32sunu   =>  Sun Ultra 32-bit makefile
+ makefile.64sunu   =>  Sun Ultra 64-bit makefile
+ makefile.sco      =>  For SCO OSr5  ELF and Unixware 7 with Native cc
+ makefile.mips     =>  MIPS makefile
+ makefile.acorn    =>  Acorn makefile
+ makefile.amiga    =>  Amiga makefile
+ smakefile.ppc     =>  AMIGA smakefile for SAS C V6.58/7.00 PPC compiler
+                       (Requires SCOPTIONS, copied from scripts/SCOPTIONS.ppc)
+ makefile.atari    =>  Atari makefile
+ makefile.beos     =>  BEOS makefile for X86
+ makefile.bor      =>  Borland makefile (uses bcc)
+ makefile.bc32     =>  32-bit Borland C++ (all modules compiled in C mode)
+ makefile.tc3      =>  Turbo C 3.0 makefile
+ makefile.dj2      =>  DJGPP 2 makefile
+ makefile.msc      =>  Microsoft C makefile
+ makefile.vcawin32 =>  makefile for Microsoft Visual C++ 5.0 and later (uses
+                       assembler code tuned for Intel MMX platform)
+ makefile.vcwin32  =>  makefile for Microsoft Visual C++ 4.0 and later (does
+                       not use assembler code)
+ makefile.os2      =>  OS/2 Makefile (gcc and emx, requires pngos2.def)
+ pngos2.def        =>  OS/2 module definition file used by makefile.os2
+ makefile.watcom   =>  Watcom 10a+ Makefile, 32-bit flat memory model
+ makevms.com       =>  VMS build script
+ descrip.mms       =>  VMS makefile for MMS or MMK
+ SCOPTIONS.ppc     =>  Used with smakefile.ppc
+
+Copy the file (or files) that you need from the
+scripts directory into this directory, for example
+
+   MSDOS example: copy scripts\makefile.msc makefile
+   UNIX example:    cp scripts/makefile.std makefile
+
+Read the makefile to see if you need to change any source or
+target directories to match your preferences.
+
+Then read pngconf.h to see if you want to make any configuration
+changes.
+
+Then just run "make" which will create the libpng library in
+this directory and "make test" which will run a quick test that reads
+the "pngtest.png" file and writes a "pngout.png" file that should be
+identical to it.  Look for "9782 zero samples" in the output of the
+test.  For more confidence, you can run another test by typing
+"pngtest pngnow.png" and looking for "289 zero samples" in the output.
+Also, you can run "pngtest -m contrib/pngsuite/*.png" and compare
+your output with the result shown in contrib/pngsuite/README.
+
+Most of the makefiles will allow you to run "make install" to
+put the library in its final resting place (if you want to
+do that, run "make install" in the zlib directory first if necessary).
+Some also allow you to run "make test-installed" after you have
+run "make install".
+
+If you encounter a compiler error message complaining about the
+lines
+      __png.h__ already includes setjmp.h;
+      __dont__ include it again.;
+This means you have compiled another module that includes setjmp.h,
+which is hazardous because the two modules might not include exactly
+the same setjmp.h.  If you are sure that you know what you are doing
+and that they are exactly the same, then you can comment out or
+delete the two lines.  Better yet, use the cexcept interface
+instead, as demonstrated in contrib/visupng of the libpng distribution.
+
+Further information can be found in the README and libpng.txt
+files, in the individual makefiles, in png.h, and the manual pages
+libpng.3 and png.5.
diff --git a/gs/libpng/KNOWNBUG b/gs/libpng/KNOWNBUG
new file mode 100644
index 000000000..620296f67
--- /dev/null
+++ b/gs/libpng/KNOWNBUG
@@ -0,0 +1,11 @@
+
+Known bugs in libpng version 1.2.8
+
+1. April 22, 2001: pnggccrd.c has been reported to crash on NetBSD when
+   reading interlaced PNG files, when assembler code is enabled but running
+   on a non-MMX i386 platform.
+
+   STATUS: Under investigation.  The change to pnggccrd.c in libpng-1.2.1
+   fixed a problem under FreeBSD but not the problem with NetBSD, which
+   still fails as of libpng-1.2.2rc1.
+
diff --git a/gs/libpng/LICENSE b/gs/libpng/LICENSE
new file mode 100644
index 000000000..fe3ac4b96
--- /dev/null
+++ b/gs/libpng/LICENSE
@@ -0,0 +1,109 @@
+
+This copy of the libpng notices is provided for your convenience.  In case of
+any discrepancy between this copy and the notices in the file png.h that is
+included in the libpng distribution, the latter shall prevail.
+
+COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
+
+If you modify libpng you may insert additional notices immediately following
+this sentence.
+
+libpng version 1.2.6, December 3, 2004, is
+Copyright (c) 2004 Glenn Randers-Pehrson, and is
+distributed according to the same disclaimer and license as libpng-1.2.5
+with the following individual added to the list of Contributing Authors
+
+   Cosmin Truta
+
+libpng versions 1.0.7, July 1, 2000, through 1.2.5 - October 3, 2002, are
+Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
+distributed according to the same disclaimer and license as libpng-1.0.6
+with the following individuals added to the list of Contributing Authors
+
+   Simon-Pierre Cadieux
+   Eric S. Raymond
+   Gilles Vollant
+
+and with the following additions to the disclaimer:
+
+   There is no warranty against interference with your enjoyment of the
+   library or against infringement.  There is no warranty that our
+   efforts or the library will fulfill any of your particular purposes
+   or needs.  This library is provided with all faults, and the entire
+   risk of satisfactory quality, performance, accuracy, and effort is with
+   the user.
+
+libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
+Copyright (c) 1998, 1999 Glenn Randers-Pehrson, and are
+distributed according to the same disclaimer and license as libpng-0.96,
+with the following individuals added to the list of Contributing Authors:
+
+   Tom Lane
+   Glenn Randers-Pehrson
+   Willem van Schaik
+
+libpng versions 0.89, June 1996, through 0.96, May 1997, are
+Copyright (c) 1996, 1997 Andreas Dilger
+Distributed according to the same disclaimer and license as libpng-0.88,
+with the following individuals added to the list of Contributing Authors:
+
+   John Bowler
+   Kevin Bracey
+   Sam Bushell
+   Magnus Holmgren
+   Greg Roelofs
+   Tom Tanner
+
+libpng versions 0.5, May 1995, through 0.88, January 1996, are
+Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+
+For the purposes of this copyright and license, "Contributing Authors"
+is defined as the following set of individuals:
+
+   Andreas Dilger
+   Dave Martindale
+   Guy Eric Schalnat
+   Paul Schmidt
+   Tim Wegner
+
+The PNG Reference Library is supplied "AS IS".  The Contributing Authors
+and Group 42, Inc. disclaim all warranties, expressed or implied,
+including, without limitation, the warranties of merchantability and of
+fitness for any purpose.  The Contributing Authors and Group 42, Inc.
+assume no liability for direct, indirect, incidental, special, exemplary,
+or consequential damages, which may result from the use of the PNG
+Reference Library, even if advised of the possibility of such damage.
+
+Permission is hereby granted to use, copy, modify, and distribute this
+source code, or portions hereof, for any purpose, without fee, subject
+to the following restrictions:
+
+1. The origin of this source code must not be misrepresented.
+
+2. Altered versions must be plainly marked as such and must not
+   be misrepresented as being the original source.
+
+3. This Copyright notice may not be removed or altered from any
+   source or altered source distribution.
+
+The Contributing Authors and Group 42, Inc. specifically permit, without
+fee, and encourage the use of this source code as a component to
+supporting the PNG file format in commercial products.  If you use this
+source code in a product, acknowledgment is not required but would be
+appreciated.
+
+
+A "png_get_copyright" function is available, for convenient use in "about"
+boxes and the like:
+
+   printf("%s",png_get_copyright(NULL));
+
+Also, the PNG logo (in PNG format, of course) is supplied in the
+files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
+
+Libpng is OSI Certified Open Source Software.  OSI Certified Open Source is a
+certification mark of the Open Source Initiative.
+
+Glenn Randers-Pehrson
+glennrp at users.sourceforge.net
+December 3, 2004
diff --git a/gs/libpng/README b/gs/libpng/README
new file mode 100644
index 000000000..06f9fe4d6
--- /dev/null
+++ b/gs/libpng/README
@@ -0,0 +1,262 @@
+README for libpng version 1.2.8 - December 3, 2004 (shared library 12.0)
+See the note about version numbers near the top of png.h
+
+See INSTALL for instructions on how to install libpng.
+
+Libpng comes in several distribution formats.  Get libpng-*.tar.gz
+or libpng-*.tar.bz2 if you want UNIX-style line endings in the text
+files, or lpng*.zip if you want DOS-style line endings.
+
+Version 0.89 was the first official release of libpng.  Don't let the
+fact that it's the first release fool you.  The libpng library has been in
+extensive use and testing since mid-1995.  By late 1997 it had
+finally gotten to the stage where there hadn't been significant
+changes to the API in some time, and people have a bad feeling about
+libraries with versions < 1.0.  Version 1.0.0 was released in
+March 1998.
+
+****
+Note that some of the changes to the png_info structure render this
+version of the library binary incompatible with libpng-0.89 or
+earlier versions if you are using a shared library.  The type of the
+"filler" parameter for png_set_filler() has changed from png_byte to
+png_uint_32, which will affect shared-library applications that use
+this function.
+
+To avoid problems with changes to the internals of png_info_struct,
+new APIs have been made available in 0.95 to avoid direct application
+access to info_ptr.  These functions are the png_set_<chunk> and
+png_get_<chunk> functions.  These functions should be used when
+accessing/storing the info_struct data, rather than manipulating it
+directly, to avoid such problems in the future.
+
+It is important to note that the APIs do not make current programs
+that access the info struct directly incompatible with the new
+library.  However, it is strongly suggested that new programs use
+the new APIs (as shown in example.c and pngtest.c), and older programs
+be converted to the new format, to facilitate upgrades in the future.
+****
+
+Additions since 0.90 include the ability to compile libpng as a
+Windows DLL, and new APIs for accessing data in the info struct.
+Experimental functions include the ability to set weighting and cost
+factors for row filter selection, direct reads of integers from buffers
+on big-endian processors that support misaligned data access, faster
+methods of doing alpha composition, and more accurate 16->8 bit color
+conversion.
+
+The additions since 0.89 include the ability to read from a PNG stream
+which has had some (or all) of the signature bytes read by the calling
+application.  This also allows the reading of embedded PNG streams that
+do not have the PNG file signature.  As well, it is now possible to set
+the library action on the detection of chunk CRC errors.  It is possible
+to set different actions based on whether the CRC error occurred in a
+critical or an ancillary chunk.
+
+The changes made to the library, and bugs fixed are based on discussions
+on the PNG-implement mailing list
+and not on material submitted privately to Guy, Andreas, or Glenn.  They will
+forward any good suggestions to the list.
+
+For a detailed description on using libpng, read libpng.txt.  For
+examples of libpng in a program, see example.c and pngtest.c.  For usage
+information and restrictions (what little they are) on libpng, see
+png.h.  For a description on using zlib (the compression library used by
+libpng) and zlib's restrictions, see zlib.h
+
+I have included a general makefile, as well as several machine and
+compiler specific ones, but you may have to modify one for your own needs.
+
+You should use zlib 1.0.4 or later to run this, but it MAY work with
+versions as old as zlib 0.95.  Even so, there are bugs in older zlib
+versions which can cause the output of invalid compression streams for
+some images.  You will definitely need zlib 1.0.4 or later if you are
+taking advantage of the MS-DOS "far" structure allocation for the small
+and medium memory models.  You should also note that zlib is a
+compression library that is useful for more things than just PNG files.
+You can use zlib as a drop-in replacement for fread() and fwrite() if
+you are so inclined.
+
+zlib should be available at the same place that libpng is, or at.
+ftp://ftp.info-zip.org/pub/infozip/zlib
+
+You may also want a copy of the PNG specification.  It is available
+as an RFC, a W3C Recommendation, and an ISO/IEC Standard.  You can find
+these at http://www.libpng.org/pub/png/documents/
+
+This code is currently being archived at libpng.sf.net in the
+[DOWNLOAD] area, and on CompuServe, Lib 20 (PNG SUPPORT)
+at GO GRAPHSUP.  If you can't find it in any of those places,
+e-mail me, and I'll help you find it.
+
+If you have any code changes, requests, problems, etc., please e-mail
+them to me.  Also, I'd appreciate any make files or project files,
+and any modifications you needed to make to get libpng to compile,
+along with a #define variable to tell what compiler/system you are on.
+If you needed to add transformations to libpng, or wish libpng would
+provide the image in a different way, drop me a note (and code, if
+possible), so I can consider supporting the transformation.
+Finally, if you get any warning messages when compiling libpng
+(note: not zlib), and they are easy to fix, I'd appreciate the
+fix.  Please mention "libpng" somewhere in the subject line.  Thanks.
+
+This release was created and will be supported by myself (of course
+based in a large way on Guy's and Andreas' earlier work), and the PNG group.
+
+glennrp at users.sourceforge.net
+png-implement at ccrc.wustl.edu (subscription required; write to
+majordomo at ccrc.wustl.edu with "subscribe png-implement" in the message).
+
+You can't reach Guy, the original libpng author, at the addresses
+given in previous versions of this document.  He and Andreas will read mail
+addressed to the png-implement list, however.
+
+Please do not send general questions about PNG.  Send them to
+the (png-list at ccrc.wustl.edu, subscription required, write to
+majordomo at ccrc.wustl.edu with "subscribe png-list" in your message).
+On the other hand,
+please do not send libpng questions to that address, send them to me
+or to the png-implement list.  I'll
+get them in the end anyway.  If you have a question about something
+in the PNG specification that is related to using libpng, send it
+to me.  Send me any questions that start with "I was using libpng,
+and ...".  If in doubt, send questions to me.  I'll bounce them
+to others, if necessary.
+
+Please do not send suggestions on how to change PNG.  We have
+been discussing PNG for nine years now, and it is official and
+finished.  If you have suggestions for libpng, however, I'll
+gladly listen.  Even if your suggestion is not used immediately,
+it may be used later.
+
+Files in this distribution:
+
+      ANNOUNCE      =>  Announcement of this version, with recent changes
+      CHANGES       =>  Description of changes between libpng versions
+      KNOWNBUG      =>  List of known bugs and deficiencies
+      LICENSE       =>  License to use and redistribute libpng
+      README        =>  This file
+      TODO          =>  Things not implemented in the current library
+      Y2KINFO       =>  Statement of Y2K compliance
+      example.c     =>  Example code for using libpng functions
+      libpng.3      =>  manual page for libpng (includes libpng.txt)
+      libpng.txt    =>  Description of libpng and its functions
+      libpngpf.3    =>  manual page for libpng's private functions
+      png.5         =>  manual page for the PNG format
+      png.c         =>  Basic interface functions common to library
+      png.h         =>  Library function and interface declarations
+      pngconf.h     =>  System specific library configuration
+      pngasmrd.h    =>  Header file for assembler-coded functions
+      pngerror.c    =>  Error/warning message I/O functions
+      pngget.c      =>  Functions for retrieving info from struct
+      pngmem.c      =>  Memory handling functions
+      pngbar.png    =>  PNG logo, 88x31
+      pngnow.png    =>  PNG logo, 98x31
+      pngpread.c    =>  Progressive reading functions
+      pngread.c     =>  Read data/helper high-level functions
+      pngrio.c      =>  Lowest-level data read I/O functions
+      pngrtran.c    =>  Read data transformation functions
+      pngrutil.c    =>  Read data utility functions
+      pngset.c      =>  Functions for storing data into the info_struct
+      pngtest.c     =>  Library test program
+      pngtest.png   =>  Library test sample image
+      pngtrans.c    =>  Common data transformation functions
+      pngwio.c      =>  Lowest-level write I/O functions
+      pngwrite.c    =>  High-level write functions
+      pngwtran.c    =>  Write data transformations
+      pngwutil.c    =>  Write utility functions
+      contrib       =>  Contributions
+       gregbook         =>  source code for PNG reading and writing, from
+                            Greg Roelofs' "PNG: The Definitive Guide",
+                            O'Reilly, 1999
+       msvctest     =>  Builds and runs pngtest using a MSVC workspace
+       pngminus     =>  Simple pnm2png and png2pnm programs
+       pngsuite     =>  Test images
+       visupng      =>  Contains a MSVC workspace for VisualPng
+      projects      =>  Contains project files and workspaces for building DLL
+       beos             =>  Contains a Beos workspace for building libpng
+       c5builder        =>  Contains a Borland workspace for building libpng
+                            and zlib
+       visualc6         =>  Contains a Microsoft Visual C++ (MSVC) workspace
+                            for building libpng and zlib
+       netware.txt      =>  Contains instructions for downloading a set of
+                            project files for building libpng and zlib on
+                            Netware.
+       wince.txt        =>  Contains instructions for downloading a Microsoft
+                            Visual C++ (Windows CD Toolkit) workspace for
+                            building libpng and zlib on WindowsCE
+      scripts       =>  Directory containing scripts for building libpng:
+       descrip.mms      =>  VMS makefile for MMS or MMK
+       makefile.std     =>  Generic UNIX makefile (cc, creates static libpng.a)
+       makefile.elf     =>  Linux/ELF makefile symbol versioning,
+                            gcc, creates libpng12.so.0.1.2.8)
+       makefile.linux   =>  Linux/ELF makefile
+                            (gcc, creates libpng12.so.0.1.2.8)
+       makefile.gcmmx   =>  Linux/ELF makefile
+                            (gcc, creates libpng12.so.0.1.2.8,
+                            uses assembler code tuned for Intel MMX platform)
+       makefile.gcc     =>  Generic makefile (gcc, creates static libpng.a)
+       makefile.knr     =>  Archaic UNIX Makefile that converts files with
+                            ansi2knr (Requires ansi2knr.c from
+                            ftp://ftp.cs.wisc.edu/ghost)
+       makefile.aix     =>  AIX makefile
+       makefile.cygwin  =>  Cygwin/gcc makefile
+       makefile.darwin  =>  Darwin makefile
+       makefile.dec     =>  DEC Alpha UNIX makefile
+       makefile.freebsd =>  FreeBSD makefile
+       makefile.hpgcc   =>  HPUX makefile using gcc
+       makefile.hpux    =>  HPUX (10.20 and 11.00) makefile
+       makefile.hp64    =>  HPUX (10.20 and 11.00) makefile, 64 bit
+       makefile.ibmc    =>  IBM C/C++ version 3.x for Win32 and OS/2 (static)
+       makefile.intel   =>  Intel C/C++ version 4.0 and later
+       libpng.icc       =>  Project file, IBM VisualAge/C++ 4.0 or later
+       makefile.netbsd  =>  NetBSD/cc makefile, PNGGCCRD, makes libpng.so.
+       makefile.ne12bsd  =>  NetBSD/cc makefile, PNGGCCRD, makes libpng12.so
+       makefile.openbsd =>  OpenBSD makefile
+       makefile.sgi     =>  Silicon Graphics IRIX (cc, creates static lib)
+       makefile.sggcc   =>  Silicon Graphics
+                            (gcc, creates libpng12.so.0.1.2.8)
+       makefile.sunos   =>  Sun makefile
+       makefile.solaris =>  Solaris 2.X makefile
+                            (gcc, creates libpng12.so.0.1.2.8)
+       makefile.so9     =>  Solaris 9 makefile
+                            (gcc, creates libpng12.so.0.1.2.8)
+       makefile.32sunu  =>  Sun Ultra 32-bit makefile
+       makefile.64sunu  =>  Sun Ultra 64-bit makefile
+       makefile.sco     =>  For SCO OSr5  ELF and Unixware 7 with Native cc
+       makefile.mips    =>  MIPS makefile
+       makefile.acorn   =>  Acorn makefile
+       makefile.amiga   =>  Amiga makefile
+       smakefile.ppc    =>  AMIGA smakefile for SAS C V6.58/7.00 PPC
+                            compiler (Requires SCOPTIONS, copied from
+                            scripts/SCOPTIONS.ppc)
+       makefile.atari   =>  Atari makefile
+       makefile.beos    =>  BEOS makefile for X86
+       makefile.bor     =>  Borland makefile (uses bcc)
+       makefile.bc32    =>  32-bit Borland C++ (all modules compiled in C mode)
+       makefile.tc3     =>  Turbo C 3.0 makefile
+       makefile.dj2     =>  DJGPP 2 makefile
+       makefile.msc     =>  Microsoft C makefile
+       makefile.vcawin32=>  makefile for Microsoft Visual C++ 5.0 and
+                            later (uses assembler code tuned for Intel MMX
+                            platform)
+       makefile.vcwin32 =>  makefile for Microsoft Visual C++ 4.0 and
+                            later (does not use assembler code)
+       makefile.os2     =>  OS/2 Makefile (gcc and emx, requires pngos2.def)
+       pngos2.def       =>  OS/2 module definition file used by makefile.os2
+       makefile.watcom  =>  Watcom 10a+ Makefile, 32-bit flat memory model
+       makevms.com      =>  VMS build script
+       SCOPTIONS.ppc    =>  Used with smakefile.ppc
+
+Good luck, and happy coding.
+
+-Glenn Randers-Pehrson (current maintainer)
+ Internet: glennrp at users.sourceforge.net
+
+-Andreas Eric Dilger (former maintainer, 1996-1997)
+ Internet: adilger at enel.ucalgary.ca
+ Web: http://www-mddsp.enel.ucalgary.ca/People/adilger/
+
+-Guy Eric Schalnat (original author and former maintainer, 1995-1996)
+ (formerly of Group 42, Inc)
+ Internet: gschal at infinet.com
diff --git a/gs/libpng/TODO b/gs/libpng/TODO
new file mode 100644
index 000000000..a5f639577
--- /dev/null
+++ b/gs/libpng/TODO
@@ -0,0 +1,24 @@
+TODO - list of things to do for libpng:
+
+Final bug fixes.
+Improve API by hiding the png_struct and png_info structs.
+Finish work on the no-floating-point version (including gamma compensation)
+Better C++ wrapper/full C++ implementation?
+Fix problem with C++ and EXTERN "C".
+cHRM transformation.
+Improve setjmp/longjmp usage or remove it in favor of returning error codes.
+Add "grayscale->palette" transformation and "palette->grayscale" detection.
+Improved dithering.
+Multi-lingual error and warning message support.
+Complete sRGB transformation (presently it simply uses gamma=0.45455).
+Man pages for function calls.
+Better documentation.
+Better filter selection
+   (counting huffman bits/precompression?  filter inertia?  filter costs?).
+Histogram creation.
+Text conversion between different code pages (Latin-1 -> Mac and DOS).
+Should we always malloc 2^bit_depth PLTE/tRNS/hIST entries for safety?
+Build gamma tables using fixed point (and do away with floating point entirely).
+Use greater precision when changing to linear gamma for compositing against
+  background and doing rgb-to-gray transformation.
+Investigate pre-incremented loop counters and other loop constructions.
diff --git a/gs/libpng/Y2KINFO b/gs/libpng/Y2KINFO
new file mode 100644
index 000000000..4db294fb5
--- /dev/null
+++ b/gs/libpng/Y2KINFO
@@ -0,0 +1,55 @@
+   Y2K compliance in libpng:
+   =========================
+
+      December 3, 2004
+
+      Since the PNG Development group is an ad-hoc body, we can't make
+      an official declaration.
+
+      This is your unofficial assurance that libpng from version 0.71 and
+      upward through 1.2.8 are Y2K compliant.  It is my belief that earlier
+      versions were also Y2K compliant.
+
+      Libpng only has three year fields.  One is a 2-byte unsigned integer
+      that will hold years up to 65535.  The other two hold the date in text
+      format, and will hold years up to 9999.
+
+      The integer is
+          "png_uint_16 year" in png_time_struct.
+
+      The strings are
+          "png_charp time_buffer" in png_struct and
+          "near_time_buffer", which is a local character string in png.c.
+
+      There are seven time-related functions:
+
+          png_convert_to_rfc_1123() in png.c
+            (formerly png_convert_to_rfc_1152() in error)
+          png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
+          png_convert_from_time_t() in pngwrite.c
+          png_get_tIME() in pngget.c
+          png_handle_tIME() in pngrutil.c, called in pngread.c
+          png_set_tIME() in pngset.c
+          png_write_tIME() in pngwutil.c, called in pngwrite.c
+
+      All appear to handle dates properly in a Y2K environment.  The
+      png_convert_from_time_t() function calls gmtime() to convert from system
+      clock time, which returns (year - 1900), which we properly convert to
+      the full 4-digit year.  There is a possibility that applications using
+      libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
+      function, or that they are incorrectly passing only a 2-digit year
+      instead of "year - 1900" into the png_convert_from_struct_tm() function,
+      but this is not under our control.  The libpng documentation has always
+      stated that it works with 4-digit years, and the APIs have been
+      documented as such.
+
+      The tIME chunk itself is also Y2K compliant.  It uses a 2-byte unsigned
+      integer to hold the year, and can hold years as large as 65535.
+
+      zlib, upon which libpng depends, is also Y2K compliant.  It contains
+      no date-related code.
+
+
+         Glenn Randers-Pehrson
+         libpng maintainer
+         PNG Development Group
diff --git a/gs/libpng/configure b/gs/libpng/configure
new file mode 100755
index 000000000..f7affd5cc
--- /dev/null
+++ b/gs/libpng/configure
@@ -0,0 +1,13 @@
+#!/bin/sh
+echo "
+  There is no \"configure\" script in this distribution of
+  libpng-1.2.8.
+
+  Instead, please copy the appropriate makefile for your system from the
+  \"scripts\" directory.  Read the INSTALL file for more details.
+
+  Update, July 2004: you can get a "configure" based distribution
+  from the libpng distribution sites.  Download the file
+  libpng-1.2.8-config.tar.gz
+"
+
diff --git a/gs/libpng/contrib/gregbook/LICENSE b/gs/libpng/contrib/gregbook/LICENSE
new file mode 100644
index 000000000..175ebfdf4
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/LICENSE
@@ -0,0 +1,26 @@
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2001 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------
diff --git a/gs/libpng/contrib/gregbook/Makefile.sgi b/gs/libpng/contrib/gregbook/Makefile.sgi
new file mode 100644
index 000000000..e3ca6ce4c
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/Makefile.sgi
@@ -0,0 +1,104 @@
+# Sample makefile for rpng-x / rpng2-x / wpng for SGI using cc and make.
+# Greg Roelofs
+# Last modified:  7 March 2002
+#
+#	The programs built by this makefile are described in the book,
+#	"PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
+#	Associates, 1999).  Go buy a copy, eh?  Buy some for friends
+#	and family, too.  (Not that this is a blatant plug or anything.)
+#
+# Invoke this makefile from a shell prompt in the usual way; for example:
+#
+#	make -f Makefile.sgi
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are both installed in /usr/local/{include,lib} (as indicated by the
+# PNG* and Z* macros below).  Edit as appropriate--choose only ONE each of
+# the PNGINC, PNGLIB, ZINC and ZLIB lines.
+#
+# This makefile builds dynamically linked executables (against libpng and zlib,
+# that is), but that can be changed by uncommenting the appropriate PNGLIB and
+# ZLIB lines.
+
+
+# macros --------------------------------------------------------------------
+
+PNGINC = -I/usr/local/include/libpng12
+PNGLIB = -L/usr/local/lib -lpng12	  # dynamically linked against libpng
+#PNGLIB = /usr/local/lib/libpng12.a # statically linked against libpng
+# or:
+#PNGINC = -I../..
+#PNGLIB = -L../.. -lpng
+#PNGLIB = ../../libpng.a
+
+ZINC = -I/usr/local/include
+ZLIB = -L/usr/local/lib -lz		# dynamically linked against zlib
+#ZLIB = /usr/local/lib/libz.a		# statically linked against zlib
+#ZINC = -I../zlib
+#ZLIB = -L../zlib -lz
+#ZLIB = ../../../zlib/libz.a
+
+XINC = -I/usr/include/X11		# old-style, stock X distributions
+XLIB = -L/usr/lib/X11 -lX11
+#XINC = -I/usr/openwin/include    	# Sun workstations (OpenWindows)
+#XLIB = -L/usr/openwin/lib -lX11
+#XINC = -I/usr/X11R6/include		# new X distributions (XFree86, etc.)
+#XLIB = -L/usr/X11R6/lib -lX11
+
+INCS = $(PNGINC) $(ZINC) $(XINC)
+RLIBS = $(PNGLIB) $(ZLIB) $(XLIB) -lm
+WLIBS = $(PNGLIB) $(ZLIB)
+
+CC = cc
+LD = cc
+RM = rm -f
+# ABI must be the same as that used to build libpng.
+ABI=
+CFLAGS = $(ABI) -O -fullwarn $(INCS)
+LDFLAGS = $(ABI)
+O = .o
+E =
+
+RPNG  = rpng-x
+RPNG2 = rpng2-x
+WPNG  = wpng
+
+ROBJS  = $(RPNG)$(O) readpng$(O)
+ROBJS2 = $(RPNG2)$(O) readpng2$(O)
+WOBJS  = $(WPNG)$(O) writepng$(O)
+
+EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+	$(CC) -c $(CFLAGS) $<
+
+
+# dependencies --------------------------------------------------------------
+
+all:  $(EXES)
+
+$(RPNG)$(E): $(ROBJS)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBS)
+
+$(RPNG2)$(E): $(ROBJS2)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBS)
+
+$(WPNG)$(E): $(WOBJS)
+	$(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBS)
+
+$(RPNG)$(O):	$(RPNG).c readpng.h
+$(RPNG2)$(O):	$(RPNG2).c readpng2.h
+$(WPNG)$(O):	$(WPNG).c writepng.h
+
+readpng$(O):	readpng.c readpng.h
+readpng2$(O):	readpng2.c readpng2.h
+writepng$(O):	writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+	$(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)
diff --git a/gs/libpng/contrib/gregbook/Makefile.unx b/gs/libpng/contrib/gregbook/Makefile.unx
new file mode 100644
index 000000000..c0c3fb1c3
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/Makefile.unx
@@ -0,0 +1,104 @@
+# Sample makefile for rpng-x / rpng2-x / wpng using gcc and make.
+# Greg Roelofs
+# Last modified:  7 March 2002
+#
+#	The programs built by this makefile are described in the book,
+#	"PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
+#	Associates, 1999).  Go buy a copy, eh?  Buy some for friends
+#	and family, too.  (Not that this is a blatant plug or anything.)
+#
+# Invoke this makefile from a shell prompt in the usual way; for example:
+#
+#	make -f Makefile.unx
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are both installed in /usr/local/{include,lib} (as indicated by the
+# PNG* and Z* macros below).  Edit as appropriate--choose only ONE each of
+# the PNGINC, PNGLIB, ZINC and ZLIB lines.
+#
+# This makefile builds statically linked executables (against libpng and zlib,
+# that is), but that can be changed by uncommenting the appropriate PNGLIB and
+# ZLIB lines.
+
+
+# macros --------------------------------------------------------------------
+
+PNGINC = -I/usr/local/include/libpng12
+#PNGLIB = -L/usr/local/lib -lpng12 # dynamically linked against libpng
+PNGLIB = /usr/local/lib/libpng12.a # statically linked against libpng
+# or:
+#PNGINC = -I../libpng
+#PNGLIB = -L../libpng -lpng
+#PNGLIB = ../libpng/libpng.a
+
+ZINC = -I/usr/local/include
+#ZLIB = -L/usr/local/lib -lz		# dynamically linked against zlib
+ZLIB = /usr/local/lib/libz.a		# statically linked against zlib
+#ZINC = -I../zlib
+#ZLIB = -L../zlib -lz
+#ZLIB = ../zlib/libz.a
+
+#XINC = -I/usr/include			# old-style, stock X distributions
+#XLIB = -L/usr/lib/X11 -lX11
+#XINC = -I/usr/openwin/include		# Sun workstations (OpenWindows)
+#XLIB = -L/usr/openwin/lib -lX11
+XINC = -I/usr/X11R6/include		# new X distributions (XFree86, etc.)
+XLIB = -L/usr/X11R6/lib -lX11
+
+INCS = $(PNGINC) $(ZINC) $(XINC)
+RLIBS = $(PNGLIB) $(ZLIB) $(XLIB) -lm
+WLIBS = $(PNGLIB) $(ZLIB)
+
+CC = gcc
+LD = gcc
+RM = rm -f
+CFLAGS = -O -Wall $(INCS)
+# [note that -Wall is a gcc-specific compilation flag ("most warnings on")]
+# [-ansi, -pedantic and -W can also be used]
+LDFLAGS =
+O = .o
+E =
+
+RPNG  = rpng-x
+RPNG2 = rpng2-x
+WPNG  = wpng
+
+ROBJS  = $(RPNG)$(O) readpng$(O)
+ROBJS2 = $(RPNG2)$(O) readpng2$(O)
+WOBJS  = $(WPNG)$(O) writepng$(O)
+
+EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+	$(CC) -c $(CFLAGS) $<
+
+
+# dependencies --------------------------------------------------------------
+
+all:  $(EXES)
+
+$(RPNG)$(E): $(ROBJS)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBS)
+
+$(RPNG2)$(E): $(ROBJS2)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBS)
+
+$(WPNG)$(E): $(WOBJS)
+	$(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBS)
+
+$(RPNG)$(O):	$(RPNG).c readpng.h
+$(RPNG2)$(O):	$(RPNG2).c readpng2.h
+$(WPNG)$(O):	$(WPNG).c writepng.h
+
+readpng$(O):	readpng.c readpng.h
+readpng2$(O):	readpng2.c readpng2.h
+writepng$(O):	writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+	$(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)
diff --git a/gs/libpng/contrib/gregbook/Makefile.w32 b/gs/libpng/contrib/gregbook/Makefile.w32
new file mode 100644
index 000000000..62041cd96
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/Makefile.w32
@@ -0,0 +1,112 @@
+# Sample makefile for rpng-win / rpng2-win / wpng using MSVC and NMAKE.
+# Greg Roelofs
+# Last modified:  16 February 1999
+#
+#	The programs built by this makefile are described in the book,
+#	"PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
+#	Associates, 1999).  Go buy a copy, eh?  Buy some for friends
+#	and family, too.  (Not that this is a blatant plug or anything.)
+#
+# Invoke this makefile from a DOS prompt window via:
+#
+#	%devstudio%\vc\bin\vcvars32.bat
+#	nmake -nologo -f Makefile.w32
+#
+# where %devstudio% is the installation directory for MSVC / DevStudio.  If
+# you get "environment out of space" errors, create a desktop shortcut with
+# "c:\windows\command.com /e:4096" as the program command line and set the
+# working directory to this directory.  Then double-click to open the new
+# DOS-prompt window with a bigger environment and retry the commands above.
+# 
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are in subdirectories at the same level as the current subdirectory
+# (as indicated by the PNGPATH and ZPATH macros below).  Edit as appropriate.
+#
+# Note that the names of the dynamic and static libpng and zlib libraries
+# used below may change in later releases of the libraries.  This makefile
+# builds statically linked executables, but that can be changed by uncom-
+# menting the appropriate PNGLIB and ZLIB lines.
+
+!include <ntwin32.mak>
+
+
+# macros --------------------------------------------------------------------
+
+PNGPATH = ../libpng
+PNGINC = -I$(PNGPATH)
+#PNGLIB = $(PNGPATH)/pngdll.lib
+PNGLIB = $(PNGPATH)/libpng.lib
+
+ZPATH = ../zlib
+ZINC = -I$(ZPATH)
+#ZLIB = $(ZPATH)/zlibdll.lib
+ZLIB = $(ZPATH)/zlibstat.lib
+
+WINLIBS = -defaultlib:user32.lib gdi32.lib
+# ["real" apps may also need comctl32.lib, comdlg32.lib, winmm.lib, etc.]
+
+INCS = $(PNGINC) $(ZINC)
+RLIBS = $(PNGLIB) $(ZLIB) $(WINLIBS)
+WLIBS = $(PNGLIB) $(ZLIB)
+
+CC = cl
+LD = link
+RM = del
+CFLAGS = -nologo -O -W3 $(INCS) $(cvars)
+# [note that -Wall is an MSVC-specific compilation flag ("all warnings on")]
+# [see %devstudio%\vc\include\win32.mak for cvars macro definition]
+O = .obj
+E = .exe
+
+RLDFLAGS = -nologo -subsystem:windows
+WLDFLAGS = -nologo
+
+RPNG  = rpng-win
+RPNG2 = rpng2-win
+WPNG  = wpng
+
+ROBJS  = $(RPNG)$(O) readpng$(O)
+ROBJS2 = $(RPNG2)$(O) readpng2$(O)
+WOBJS  = $(WPNG)$(O) writepng$(O)
+
+EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+	$(CC) -c $(CFLAGS) $<
+
+
+# dependencies --------------------------------------------------------------
+
+all:  $(EXES)
+
+$(RPNG)$(E): $(ROBJS)
+	$(LD) $(RLDFLAGS) -out:$@ $(ROBJS) $(RLIBS)
+
+$(RPNG2)$(E): $(ROBJS2)
+	$(LD) $(RLDFLAGS) -out:$@ $(ROBJS2) $(RLIBS)
+
+$(WPNG)$(E): $(WOBJS)
+	$(LD) $(WLDFLAGS) -out:$@ $(WOBJS) $(WLIBS)
+
+$(RPNG)$(O):	$(RPNG).c readpng.h
+$(RPNG2)$(O):	$(RPNG2).c readpng2.h
+$(WPNG)$(O):	$(WPNG).c writepng.h
+
+readpng$(O):	readpng.c readpng.h
+readpng2$(O):	readpng2.c readpng2.h
+writepng$(O):	writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+#	ideally we could just do this:
+#	$(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)
+#	...but the Windows "DEL" command is none too bright, so:
+	$(RM) r*$(E)
+	$(RM) w*$(E)
+	$(RM) r*$(O)
+	$(RM) w*$(O)
diff --git a/gs/libpng/contrib/gregbook/README b/gs/libpng/contrib/gregbook/README
new file mode 100644
index 000000000..c67045cac
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/README
@@ -0,0 +1,185 @@
+                     ===========================
+                      PNG: The Definitive Guide
+                     ===========================
+
+                             Source Code
+
+Chapters 13, 14 and 15 of "PNG: The Definitive Guide" discuss three free,
+cross-platform demo programs that show how to use the libpng reference
+library:  rpng, rpng2 and wpng.  rpng and rpng2 are viewers; the first is
+a very simple example that that shows how a standard file-viewer might use
+libpng, while the second is designed to process streaming data and shows
+how a web browser might be written.  wpng is a simple command-line program
+that reads binary PGM and PPM files (the ``raw'' grayscale and RGB subsets
+of PBMPLUS/NetPBM) and converts them to PNG.
+
+The source code for all three demo programs currently compiles under
+Unix, OpenVMS, and 32-bit Windows.  (Special thanks to Martin Zinser,
+zinser@decus.de, for making the necessary changes for OpenVMS and for
+providing an appropriate build script.)  Build instructions can be found
+below.
+
+Files:
+
+   README             this file
+   LICENSE            terms of distribution and reuse (BSD-like)
+
+   Makefile.unx       Unix makefile
+   Makefile.w32       Windows (MSVC) makefile
+   makevms.com        OpenVMS build script
+
+   rpng-win.c         Windows front end for the basic viewer
+   rpng-x.c           X Window System (Unix, OpenVMS) front end
+   readpng.c          generic back end for the basic viewer
+   readpng.h          header file for the basic viewer
+
+   rpng2-win.c        Windows front end for the progressive viewer
+   rpng2-x.c          X front end for the progressive viewer
+   readpng2.c         generic back end for the progressive viewer
+   readpng2.h         header file for the progressive viewer
+
+   wpng.c             generic (text) front end for the converter
+   writepng.c         generic back end for the converter
+   writepng.h         header file for the converter
+
+   toucan.png         transparent PNG for testing (by Stefan Schneider)
+
+Note that, although the programs are designed to be functional, their
+primary purpose is to illustrate how to use libpng to add PNG support to
+other programs.  As such, their user interfaces are crude and definitely
+are not intended for everyday use.
+
+Please see http://www.libpng.org/pub/png/pngbook.html for further infor-
+mation and links to the latest version of the source code, and Chapters
+13-15 of the book for detailed discussion of the three programs.
+
+Greg Roelofs
+newt@pobox.com
+30 June 2001
+
+
+BUILD INSTRUCTIONS
+
+ - Prerequisites (in order of compilation):
+
+      - zlib		http://www.gzip.org/zlib/
+      - libpng		http://www.libpng.org/pub/png/libpng.html
+      - pngbook		http://www.libpng.org/pub/png/book/sources.html
+
+     The pngbook demo programs are explicitly designed to demonstrate proper
+     coding techniques for using the libpng reference library.  As a result,
+     you need to download and build both zlib (on which libpng depends) and
+     libpng.  A common build setup is to place the zlib, libpng and pngbook
+     subdirectory trees ("folders") in the same parent directory.  Then the
+     libpng build can refer to files in ../zlib (or ..\zlib or [-.zlib]),
+     and similarly for the pngbook build.
+
+     Note that all three packages are designed to be built from a command
+     line by default; those who wish to use a graphical or other integrated
+     development environments are on their own.
+
+
+ - Unix:
+
+     Unpack the latest pngbook sources (which should correspond to this
+     README file) into a directory and change into that directory.
+
+     Copy Makefile.unx to Makefile and edit the PNG* and Z* variables
+     appropriately (possibly also the X* variables if necessary).
+
+     make
+
+     There is no "install" target, so copy the three executables somewhere
+     in your path or run them from the current directory.  All three will
+     print a basic usage screen when run without any command-line arguments;
+     see the book for more details.
+
+
+ - Windows:
+
+     Unpack the latest pngbook sources (which should correspond to this
+     README file) into a folder, open a "DOS shell" or "command prompt"
+     or equivalent command-line window, and cd into the folder where you
+     unpacked the source code.
+
+     For MSVC, set up the necessary environment variables by invoking
+ 
+        %devstudio%\vc\bin\vcvars32.bat
+
+     where where %devstudio% is the installation directory for MSVC /
+     DevStudio.  If you get "environment out of space" errors under 95/98,
+     create a desktop shortcut with "c:\windows\command.com /e:4096" as
+     the program command line and set the working directory to the pngbook
+     directory.  Then double-click to open the new DOS-prompt window with
+     a bigger environment and retry the commands above.
+
+     Copy Makefile.w32 to Makefile and edit the PNGPATH and ZPATH variables
+     appropriately (possibly also the "INC" and "LIB" variables if needed).
+     Note that the names of the dynamic and static libpng and zlib libraries
+     used in the makefile may change in later releases of the libraries.
+     Also note that, as of libpng version 1.0.5, MSVC DLL builds do not work.
+     This makefile therefore builds statically linked executables, but if
+     the DLL problems ever get fixed, uncommenting the appropriate PNGLIB
+     and ZLIB lines will build dynamically linked executables instead.
+
+     Do the build by typing
+
+        nmake
+
+     The result should be three executables:  rpng-win.exe, rpng2-win.exe,
+     and wpng.exe.  Copy them somewhere in your PATH or run them from the
+     current folder.  Like the Unix versions, the two windowed programs
+     (rpng and rpng2) now display a usage screen in a console window when
+     invoked without command-line arguments; this is new behavior as of
+     the June 2001 release.  Note that the programs use the Unix-style "-"
+     character to specify options, instead of the more common DOS/Windows
+     "/" character.  (For example:  "rpng2-win -bgpat 4 foo.png", not
+     "rpng2-win /bgpat 4 foo.png")
+
+
+ - OpenVMS:
+
+     Unpack the pngbook sources into a subdirectory and change into that
+     subdirectory.
+
+     Edit makevms.com appropriately, specifically the zpath and pngpath
+     variables.
+
+     @makevms
+
+     To run the programs, they probably first need to be set up as "foreign
+     symbols," with "disk" and "dir" set appropriately:
+
+     $ rpng == "$disk:[dir]rpng-x.exe"
+     $ rpng2 == "$disk:[dir]rpng2-x.exe"
+     $ wpng == "$disk:[dir]wpng.exe"
+
+     All three will print a basic usage screen when run without any command-
+     line arguments; see the book for more details.  Note that the options
+     style is Unix-like, i.e., preceded by "-" rather than "/".
+
+
+RUNNING THE PROGRAMS:  (VERY) BRIEF INTRO
+
+     rpng is a simple PNG viewer that can display transparent PNGs with a
+     specified background color; for example,
+
+	rpng -bgcolor #ff0000 toucan.png
+
+     would display the image with a red background.  rpng2 is a progressive
+     viewer that simulates a web browser in some respects; it can display
+     images against either a background color or a dynamically generated
+     background image.  For example:
+
+	rpng2 -bgpat 16 toucan.png
+
+     wpng is a purely command-line image converter from binary PBMPLUS/NetPBM
+     format (.pgm or .ppm) to PNG; for example,
+
+	wpng -time < toucan.ppm > toucan.png
+
+     would convert the specified PPM file (using redirection) to PNG, auto-
+     matically setting the PNG modification-time chunk.
+
+     All options can be abbreviated to the shortest unique value; for example,
+     "-bgc" for -bgcolor (versus "-bgp" for -bgpat), or "-g" for -gamma.
diff --git a/gs/libpng/contrib/gregbook/makevms.com b/gs/libpng/contrib/gregbook/makevms.com
new file mode 100644
index 000000000..bd37dc0d7
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/makevms.com
@@ -0,0 +1,132 @@
+$!------------------------------------------------------------------------------
+$! make "PNG: The Definitive Guide" demo programs (for X) under OpenVMS
+$!
+$! Script created by Martin Zinser for libpng; modified by Greg Roelofs
+$! for standalone pngbook source distribution.
+$!
+$!
+$!    Set locations where zlib and libpng sources live.
+$!
+$ zpath   = ""
+$ pngpath = ""
+$!
+$ if f$search("[---.zlib]zlib.h").nes."" then zpath = "[---.zlib]"
+$ if f$search("[--]png.h").nes."" then pngpath = "[--]"
+$!
+$ if f$search("[-.zlib]zlib.h").nes."" then zpath = "[-.zlib]"
+$ if f$search("[-.libpng]png.h").nes."" then pngpath = "[-.libpng]"
+$!
+$ if zpath .eqs. ""
+$ then
+$   write sys$output "zlib include not found. Exiting..."
+$   exit 2
+$ endif 
+$!
+$ if pngpath .eqs. ""
+$ then
+$   write sys$output "libpng include not found. Exiting..."
+$   exit 2
+$ endif 
+$!
+$!    Look for the compiler used.
+$!
+$ ccopt="/include=(''zpath',''pngpath')"
+$ if f$getsyi("HW_MODEL").ge.1024
+$ then
+$  ccopt = "/prefix=all"+ccopt
+$  comp  = "__decc__=1"
+$  if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$ else
+$  if f$search("SYS$SYSTEM:DECC$COMPILER.EXE").eqs.""
+$   then
+$    if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$    if f$search("SYS$SYSTEM:VAXC.EXE").eqs.""
+$     then
+$      comp  = "__gcc__=1"
+$      CC :== GCC
+$     else
+$      comp = "__vaxc__=1"
+$     endif
+$   else
+$    if f$trnlnm("SYS").eqs."" then define sys decc$library_include:
+$    ccopt = "/decc/prefix=all"+ccopt
+$    comp  = "__decc__=1"
+$  endif
+$ endif
+$ open/write lopt lib.opt
+$ write lopt "''pngpath'libpng.olb/lib"
+$ write lopt "''zpath'libz.olb/lib"
+$ close lopt
+$ open/write xopt x11.opt
+$ write xopt "sys$library:decw$xlibshr.exe/share"
+$ close xopt
+$!
+$!    Build 'em.
+$!
+$ write sys$output "Compiling PNG book programs ..."
+$   CALL MAKE readpng.OBJ "cc ''CCOPT' readpng" -
+	readpng.c readpng.h
+$   CALL MAKE readpng2.OBJ "cc ''CCOPT' readpng2" -
+	readpng2.c readpng2.h
+$   CALL MAKE writepng.OBJ "cc ''CCOPT' writepng" -
+	writepng.c writepng.h
+$   write sys$output "Building rpng-x..."
+$   CALL MAKE rpng-x.OBJ "cc ''CCOPT' rpng-x" -
+	rpng-x.c readpng.h
+$   call make rpng-x.exe -
+	"LINK rpng-x,readpng,lib.opt/opt,x11.opt/opt" -
+	rpng-x.obj readpng.obj
+$   write sys$output "Building rpng2-x..."
+$   CALL MAKE rpng2-x.OBJ "cc ''CCOPT' rpng2-x" -
+	rpng2-x.c readpng2.h
+$   call make rpng2-x.exe -
+	"LINK rpng2-x,readpng2,lib.opt/opt,x11.opt/opt" -
+	rpng2-x.obj readpng2.obj
+$   write sys$output "Building wpng..."
+$   CALL MAKE wpng.OBJ "cc ''CCOPT' wpng" -
+	wpng.c writepng.h
+$   call make wpng.exe -
+	"LINK wpng,writepng,lib.opt/opt" -
+	wpng.obj writepng.obj
+$ exit
+$!
+$!
+$MAKE: SUBROUTINE   !SUBROUTINE TO CHECK DEPENDENCIES
+$ V = 'F$Verify(0)
+$! P1 = What we are trying to make
+$! P2 = Command to make it
+$! P3 - P8  What it depends on
+$
+$ If F$Search(P1) .Eqs. "" Then Goto Makeit
+$ Time = F$CvTime(F$File(P1,"RDT"))
+$arg=3
+$Loop:
+$       Argument = P'arg
+$       If Argument .Eqs. "" Then Goto Exit
+$       El=0
+$Loop2:
+$       File = F$Element(El," ",Argument)
+$       If File .Eqs. " " Then Goto Endl
+$       AFile = ""
+$Loop3:
+$       OFile = AFile
+$       AFile = F$Search(File)
+$       If AFile .Eqs. "" .Or. AFile .Eqs. OFile Then Goto NextEl
+$       If F$CvTime(F$File(AFile,"RDT")) .Ges. Time Then Goto Makeit
+$       Goto Loop3
+$NextEL:
+$       El = El + 1
+$       Goto Loop2
+$EndL:
+$ arg=arg+1
+$ If arg .Le. 8 Then Goto Loop
+$ Goto Exit
+$
+$Makeit:
+$ VV=F$VERIFY(0)
+$ write sys$output P2
+$ 'P2
+$ VV='F$Verify(VV)
+$Exit:
+$ If V Then Set Verify
+$ENDSUBROUTINE
diff --git a/gs/libpng/contrib/gregbook/readpng.c b/gs/libpng/contrib/gregbook/readpng.c
new file mode 100644
index 000000000..b8e0904e2
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/readpng.c
@@ -0,0 +1,280 @@
+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                              readpng.c
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2000 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "png.h"        /* libpng header; includes zlib.h */
+#include "readpng.h"    /* typedefs, common macros, public prototypes */
+
+/* future versions of libpng will provide this macro: */
+#ifndef png_jmpbuf
+#  define png_jmpbuf(png_ptr)   ((png_ptr)->jmpbuf)
+#endif
+
+
+static png_structp png_ptr = NULL;
+static png_infop info_ptr = NULL;
+
+png_uint_32  width, height;
+int  bit_depth, color_type;
+uch  *image_data = NULL;
+
+
+void readpng_version_info(void)
+{
+    fprintf(stderr, "   Compiled with libpng %s; using libpng %s.\n",
+      PNG_LIBPNG_VER_STRING, png_libpng_ver);
+    fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",
+      ZLIB_VERSION, zlib_version);
+}
+
+
+/* return value = 0 for success, 1 for bad sig, 2 for bad IHDR, 4 for no mem */
+
+int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight)
+{
+    uch sig[8];
+
+
+    /* first do a quick check that the file really is a PNG image; could
+     * have used slightly more general png_sig_cmp() function instead */
+
+    fread(sig, 1, 8, infile);
+    if (!png_check_sig(sig, 8))
+        return 1;   /* bad signature */
+
+
+    /* could pass pointers to user-defined error handlers instead of NULLs: */
+
+    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+    if (!png_ptr)
+        return 4;   /* out of memory */
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        png_destroy_read_struct(&png_ptr, NULL, NULL);
+        return 4;   /* out of memory */
+    }
+
+
+    /* we could create a second info struct here (end_info), but it's only
+     * useful if we want to keep pre- and post-IDAT chunk info separated
+     * (mainly for PNG-aware image editors and converters) */
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(png_jmpbuf(png_ptr))) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return 2;
+    }
+
+
+    png_init_io(png_ptr, infile);
+    png_set_sig_bytes(png_ptr, 8);  /* we already read the 8 signature bytes */
+
+    png_read_info(png_ptr, info_ptr);  /* read all PNG info up to image data */
+
+
+    /* alternatively, could make separate calls to png_get_image_width(),
+     * etc., but want bit_depth and color_type for later [don't care about
+     * compression_type and filter_type => NULLs] */
+
+    png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+      NULL, NULL, NULL);
+    *pWidth = width;
+    *pHeight = height;
+
+
+    /* OK, that's all we need for now; return happy */
+
+    return 0;
+}
+
+
+
+
+/* returns 0 if succeeds, 1 if fails due to no bKGD chunk, 2 if libpng error;
+ * scales values to 8-bit if necessary */
+
+int readpng_get_bgcolor(uch *red, uch *green, uch *blue)
+{
+    png_color_16p pBackground;
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(png_jmpbuf(png_ptr))) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return 2;
+    }
+
+
+    if (!png_get_valid(png_ptr, info_ptr, PNG_INFO_bKGD))
+        return 1;
+
+    /* it is not obvious from the libpng documentation, but this function
+     * takes a pointer to a pointer, and it always returns valid red, green
+     * and blue values, regardless of color_type: */
+
+    png_get_bKGD(png_ptr, info_ptr, &pBackground);
+
+
+    /* however, it always returns the raw bKGD data, regardless of any
+     * bit-depth transformations, so check depth and adjust if necessary */
+
+    if (bit_depth == 16) {
+        *red   = pBackground->red   >> 8;
+        *green = pBackground->green >> 8;
+        *blue  = pBackground->blue  >> 8;
+    } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
+        if (bit_depth == 1)
+            *red = *green = *blue = pBackground->gray? 255 : 0;
+        else if (bit_depth == 2)
+            *red = *green = *blue = (255/3) * pBackground->gray;
+        else /* bit_depth == 4 */
+            *red = *green = *blue = (255/15) * pBackground->gray;
+    } else {
+        *red   = (uch)pBackground->red;
+        *green = (uch)pBackground->green;
+        *blue  = (uch)pBackground->blue;
+    }
+
+    return 0;
+}
+
+
+
+
+/* display_exponent == LUT_exponent * CRT_exponent */
+
+uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
+{
+    double  gamma;
+    png_uint_32  i, rowbytes;
+    png_bytepp  row_pointers = NULL;
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(png_jmpbuf(png_ptr))) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return NULL;
+    }
+
+
+    /* expand palette images to RGB, low-bit-depth grayscale images to 8 bits,
+     * transparency chunks to full alpha channel; strip 16-bit-per-sample
+     * images to 8 bits per sample; and convert grayscale to RGB[A] */
+
+    if (color_type == PNG_COLOR_TYPE_PALETTE)
+        png_set_expand(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+        png_set_expand(png_ptr);
+    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+        png_set_expand(png_ptr);
+    if (bit_depth == 16)
+        png_set_strip_16(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY ||
+        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+        png_set_gray_to_rgb(png_ptr);
+
+
+    /* unlike the example in the libpng documentation, we have *no* idea where
+     * this file may have come from--so if it doesn't have a file gamma, don't
+     * do any correction ("do no harm") */
+
+    if (png_get_gAMA(png_ptr, info_ptr, &gamma))
+        png_set_gamma(png_ptr, display_exponent, gamma);
+
+
+    /* all transformations have been registered; now update info_ptr data,
+     * get rowbytes and channels, and allocate image memory */
+
+    png_read_update_info(png_ptr, info_ptr);
+
+    *pRowbytes = rowbytes = png_get_rowbytes(png_ptr, info_ptr);
+    *pChannels = (int)png_get_channels(png_ptr, info_ptr);
+
+    if ((image_data = (uch *)malloc(rowbytes*height)) == NULL) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return NULL;
+    }
+    if ((row_pointers = (png_bytepp)malloc(height*sizeof(png_bytep))) == NULL) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        free(image_data);
+        image_data = NULL;
+        return NULL;
+    }
+
+    Trace((stderr, "readpng_get_image:  channels = %d, rowbytes = %ld, height = %ld\n", *pChannels, rowbytes, height));
+
+
+    /* set the individual row_pointers to point at the correct offsets */
+
+    for (i = 0;  i < height;  ++i)
+        row_pointers[i] = image_data + i*rowbytes;
+
+
+    /* now we can go ahead and just read the whole image */
+
+    png_read_image(png_ptr, row_pointers);
+
+
+    /* and we're done!  (png_read_end() can be omitted if no processing of
+     * post-IDAT text/time/etc. is desired) */
+
+    free(row_pointers);
+    row_pointers = NULL;
+
+    png_read_end(png_ptr, NULL);
+
+    return image_data;
+}
+
+
+void readpng_cleanup(int free_image_data)
+{
+    if (free_image_data && image_data) {
+        free(image_data);
+        image_data = NULL;
+    }
+
+    if (png_ptr && info_ptr) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        png_ptr = NULL;
+        info_ptr = NULL;
+    }
+}
diff --git a/gs/libpng/contrib/gregbook/readpng.h b/gs/libpng/contrib/gregbook/readpng.h
new file mode 100644
index 000000000..1c19aca99
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/readpng.h
@@ -0,0 +1,64 @@
+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                              readpng.h
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2000 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#ifndef TRUE
+#  define TRUE 1
+#  define FALSE 0
+#endif
+
+#ifndef MAX
+#  define MAX(a,b)  ((a) > (b)? (a) : (b))
+#  define MIN(a,b)  ((a) < (b)? (a) : (b))
+#endif
+
+#ifdef DEBUG
+#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}
+#else
+#  define Trace(x)  ;
+#endif
+
+typedef unsigned char   uch;
+typedef unsigned short  ush;
+typedef unsigned long   ulg;
+
+
+/* prototypes for public functions in readpng.c */
+
+void readpng_version_info(void);
+
+int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight);
+
+int readpng_get_bgcolor(uch *bg_red, uch *bg_green, uch *bg_blue);
+
+uch *readpng_get_image(double display_exponent, int *pChannels,
+                       ulg *pRowbytes);
+
+void readpng_cleanup(int free_image_data);
diff --git a/gs/libpng/contrib/gregbook/readpng2.c b/gs/libpng/contrib/gregbook/readpng2.c
new file mode 100644
index 000000000..9e66a0bce
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/readpng2.c
@@ -0,0 +1,624 @@
+/*---------------------------------------------------------------------------
+
+   rpng2 - progressive-model PNG display program                 readpng2.c
+
+  ---------------------------------------------------------------------------
+
+   Changelog:
+    - 1.01:  initial public release
+    - 1.02:  added code to skip unused chunks (GR-P)
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2002 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+
+#include <stdlib.h>     /* for exit() prototype */
+
+#include "png.h"        /* libpng header; includes zlib.h and setjmp.h */
+#include "readpng2.h"   /* typedefs, common macros, public prototypes */
+
+
+/* local prototypes */
+
+static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr);
+static void readpng2_row_callback(png_structp png_ptr, png_bytep new_row,
+                                 png_uint_32 row_num, int pass);
+static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr);
+static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg);
+
+
+
+
+void readpng2_version_info(void)
+{
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && \
+    (defined(__i386__) || defined(_M_IX86)) && \
+    defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+    /*
+     * WARNING:  This preprocessor approach means that the following code
+     *           cannot be used with a libpng DLL older than 1.2.0--the
+     *           compiled-in symbols for the new functions will not exist.
+     *           (Could use dlopen() and dlsym() on Unix and corresponding
+     *           calls for Windows, but not portable...)
+     */
+    {
+        int mmxsupport = png_mmx_support();
+        if (mmxsupport < 0)
+            fprintf(stderr, "   Compiled with libpng %s; using libpng %s "
+              "without MMX support.\n", PNG_LIBPNG_VER_STRING, png_libpng_ver);
+        else {
+            int compilerID;
+            png_uint_32 mmx_mask = png_get_mmx_flagmask(
+              PNG_SELECT_READ | PNG_SELECT_WRITE, &compilerID);
+
+            fprintf(stderr, "   Compiled with libpng %s; using libpng %s "
+              "with MMX support\n   (%s version).", PNG_LIBPNG_VER_STRING,
+              png_libpng_ver, compilerID == 1? "MSVC++" :
+              (compilerID == 2? "GNU C" : "unknown"));
+            fprintf(stderr, "  Processor %s MMX instructions.\n",
+              mmxsupport? "supports" : "does not support");
+            if (mmxsupport > 0) {
+                int num_optims = 0;
+
+                fprintf(stderr,
+                  "      Potential MMX optimizations supported by libpng:\n");
+                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_SUB)
+                    ++num_optims;
+                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_UP)
+                    ++num_optims;
+                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_AVG)
+                    ++num_optims;
+                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_PAETH)
+                    ++num_optims;
+                if (num_optims)
+                    fprintf(stderr,
+                      "         decoding %s row filters (reading)\n",
+                      (num_optims == 4)? "all non-trivial" : "some");
+                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW) {
+                    fprintf(stderr, "         combining rows (reading)\n");
+                    ++num_optims;
+                }
+                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_INTERLACE) {
+                    fprintf(stderr,
+                      "         expanding interlacing (reading)\n");
+                    ++num_optims;
+                }
+                mmx_mask &= ~( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
+                             | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
+                             | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
+                             | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
+                             | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
+                             | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH );
+                if (mmx_mask) {
+                    fprintf(stderr, "         other (unknown)\n");
+                    ++num_optims;
+                }
+                if (num_optims == 0)
+                    fprintf(stderr, "         (none)\n");
+            }
+        }
+    }
+#else
+    fprintf(stderr, "   Compiled with libpng %s; using libpng %s "
+      "without MMX support.\n", PNG_LIBPNG_VER_STRING, png_libpng_ver);
+#endif
+
+    fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",
+      ZLIB_VERSION, zlib_version);
+}
+
+
+
+
+int readpng2_check_sig(uch *sig, int num)
+{
+    return png_check_sig(sig, num);
+}
+
+
+
+
+/* returns 0 for success, 2 for libpng problem, 4 for out of memory */
+
+int readpng2_init(mainprog_info *mainprog_ptr)
+{
+    png_structp  png_ptr;       /* note:  temporary variables! */
+    png_infop  info_ptr;
+
+
+    /* could also replace libpng warning-handler (final NULL), but no need: */
+
+    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,
+      readpng2_error_handler, NULL);
+    if (!png_ptr)
+        return 4;   /* out of memory */
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        png_destroy_read_struct(&png_ptr, NULL, NULL);
+        return 4;   /* out of memory */
+    }
+
+
+    /* we could create a second info struct here (end_info), but it's only
+     * useful if we want to keep pre- and post-IDAT chunk info separated
+     * (mainly for PNG-aware image editors and converters) */
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function, unless an alternate error handler was installed--
+     * but compatible error handlers must either use longjmp() themselves
+     * (as in this program) or exit immediately, so here we are: */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return 2;
+    }
+
+    /* prepare the reader to ignore all recognized chunks whose data isn't
+     * going to be used, i.e., all chunks recognized by libpng except for
+     * IHDR, PLTE, IDAT, IEND, tRNS, bKGD, gAMA, and sRGB : */
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+    {
+#ifndef HANDLE_CHUNK_NEVER
+/* prior to libpng-1.2.5, this macro was internal, so we define it here. */
+# define HANDLE_CHUNK_NEVER 1
+#endif
+       /* these byte strings were copied from png.h.
+        * If a future libpng version recognizes more chunks, add them
+        * to this list.  If a future version of readpng2.c recognizes
+        * more chunks, delete them from this list. */
+       png_byte png_chunk_types_to_ignore[]=
+          { 99,  72,  82,  77, '\0', /* cHRM */
+           104,  73,  83,  84, '\0', /* hIST */
+           105,  67,  67,  80, '\0', /* iCCP */
+           105,  84,  88, 116, '\0', /* iTXt */
+           111,  70,  70, 115, '\0', /* oFFs */
+           112,  67,  65,  76, '\0', /* pCAL */
+           115,  67,  65,  76, '\0', /* sCAL */
+           112,  72,  89, 115, '\0', /* pHYs */
+           115,  66,  73,  84, '\0', /* sBIT */
+           115,  80,  76,  84, '\0', /* sPLT */
+           116,  69,  88, 116, '\0', /* tEXt */
+           116,  73,  77,  69, '\0', /* tIME */
+           122,  84,  88, 116, '\0'}; /* zTXt */
+#define NUM_PNG_CHUNK_TYPES_TO_IGNORE 13
+
+    png_set_keep_unknown_chunks(png_ptr, HANDLE_CHUNK_NEVER,
+        png_chunk_types_to_ignore, NUM_PNG_CHUNK_TYPES_TO_IGNORE);
+    }
+#endif
+
+    /* instead of doing png_init_io() here, now we set up our callback
+     * functions for progressive decoding */
+
+    png_set_progressive_read_fn(png_ptr, mainprog_ptr,
+      readpng2_info_callback, readpng2_row_callback, readpng2_end_callback);
+
+
+    /*
+     * may as well enable or disable MMX routines here, if supported;
+     *
+     * to enable all:  mask = png_get_mmx_flagmask (
+     *                   PNG_SELECT_READ | PNG_SELECT_WRITE, &compilerID);
+     *                 flags = png_get_asm_flags (png_ptr);
+     *                 flags |= mask;
+     *                 png_set_asm_flags (png_ptr, flags);
+     *
+     * to disable all:  mask = png_get_mmx_flagmask (
+     *                   PNG_SELECT_READ | PNG_SELECT_WRITE, &compilerID);
+     *                  flags = png_get_asm_flags (png_ptr);
+     *                  flags &= ~mask;
+     *                  png_set_asm_flags (png_ptr, flags);
+     */
+
+#if (defined(__i386__) || defined(_M_IX86)) && \
+    defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+    /*
+     * WARNING:  This preprocessor approach means that the following code
+     *           cannot be used with a libpng DLL older than 1.2.0--the
+     *           compiled-in symbols for the new functions will not exist.
+     *           (Could use dlopen() and dlsym() on Unix and corresponding
+     *           calls for Windows, but not portable...)
+     */
+    {
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+        png_uint_32 mmx_disable_mask = 0;
+        png_uint_32 asm_flags, mmx_mask;
+        int compilerID;
+
+        if (mainprog_ptr->nommxfilters)
+            mmx_disable_mask |= ( PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
+                                | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
+                                | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
+                                | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH );
+        if (mainprog_ptr->nommxcombine)
+            mmx_disable_mask |= PNG_ASM_FLAG_MMX_READ_COMBINE_ROW;
+        if (mainprog_ptr->nommxinterlace)
+            mmx_disable_mask |= PNG_ASM_FLAG_MMX_READ_INTERLACE;
+        asm_flags = png_get_asm_flags(png_ptr);
+        png_set_asm_flags(png_ptr, asm_flags & ~mmx_disable_mask);
+
+
+        /* Now query libpng's asm settings, just for yuks.  Note that this
+         * differs from the querying of its *potential* MMX capabilities
+         * in readpng2_version_info(); this is true runtime verification. */
+
+        asm_flags = png_get_asm_flags(png_ptr);
+        mmx_mask = png_get_mmx_flagmask(PNG_SELECT_READ | PNG_SELECT_WRITE,
+          &compilerID);
+        if (asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_COMPILED)
+            fprintf(stderr,
+              "  MMX support (%s version) is compiled into libpng\n",
+              compilerID == 1? "MSVC++" :
+              (compilerID == 2? "GNU C" : "unknown"));
+        else
+            fprintf(stderr, "  MMX support is not compiled into libpng\n");
+        fprintf(stderr, "  MMX instructions are %ssupported by CPU\n",
+          (asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU)? "" : "not ");
+        fprintf(stderr, "  MMX read support for combining rows is %sabled\n",
+          (asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)? "en" : "dis");
+        fprintf(stderr,
+          "  MMX read support for expanding interlacing is %sabled\n",
+          (asm_flags & PNG_ASM_FLAG_MMX_READ_INTERLACE)? "en" : "dis");
+        fprintf(stderr, "  MMX read support for \"sub\" filter is %sabled\n",
+          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_SUB)? "en" : "dis");
+        fprintf(stderr, "  MMX read support for \"up\" filter is %sabled\n",
+          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_UP)? "en" : "dis");
+        fprintf(stderr, "  MMX read support for \"avg\" filter is %sabled\n",
+          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_AVG)? "en" : "dis");
+        fprintf(stderr, "  MMX read support for \"Paeth\" filter is %sabled\n",
+          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_PAETH)? "en" : "dis");
+        asm_flags &= (mmx_mask & ~( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
+                                  | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
+                                  | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
+                                  | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
+                                  | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
+                                  | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ));
+        if (asm_flags)
+            fprintf(stderr,
+              "  additional MMX support is also enabled (0x%02lx)\n",
+              asm_flags);
+#else  /* !PNG_ASSEMBLER_CODE_SUPPORTED */
+        fprintf(stderr, "  MMX querying is disabled in libpng.\n");
+#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
+    }
+#endif
+
+
+    /* make sure we save our pointers for use in readpng2_decode_data() */
+
+    mainprog_ptr->png_ptr = png_ptr;
+    mainprog_ptr->info_ptr = info_ptr;
+
+
+    /* and that's all there is to initialization */
+
+    return 0;
+}
+
+
+
+
+/* returns 0 for success, 2 for libpng (longjmp) problem */
+
+int readpng2_decode_data(mainprog_info *mainprog_ptr, uch *rawbuf, ulg length)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* hand off the next chunk of input data to libpng for decoding */
+
+    png_process_data(png_ptr, info_ptr, rawbuf, length);
+
+    return 0;
+}
+
+
+
+
+static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr)
+{
+    mainprog_info  *mainprog_ptr;
+    int  color_type, bit_depth;
+    double  gamma;
+
+
+    /* setjmp() doesn't make sense here, because we'd either have to exit(),
+     * longjmp() ourselves, or return control to libpng, which doesn't want
+     * to see us again.  By not doing anything here, libpng will instead jump
+     * to readpng2_decode_data(), which can return an error value to the main
+     * program. */
+
+
+    /* retrieve the pointer to our special-purpose struct, using the png_ptr
+     * that libpng passed back to us (i.e., not a global this time--there's
+     * no real difference for a single image, but for a multithreaded browser
+     * decoding several PNG images at the same time, one needs to avoid mixing
+     * up different images' structs) */
+
+    mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+    if (mainprog_ptr == NULL) {         /* we be hosed */
+        fprintf(stderr,
+          "readpng2 error:  main struct not recoverable in info_callback.\n");
+        fflush(stderr);
+        return;
+        /*
+         * Alternatively, we could call our error-handler just like libpng
+         * does, which would effectively terminate the program.  Since this
+         * can only happen if png_ptr gets redirected somewhere odd or the
+         * main PNG struct gets wiped, we're probably toast anyway.  (If
+         * png_ptr itself is NULL, we would not have been called.)
+         */
+    }
+
+
+    /* this is just like in the non-progressive case */
+
+    png_get_IHDR(png_ptr, info_ptr, &mainprog_ptr->width,
+      &mainprog_ptr->height, &bit_depth, &color_type, NULL, NULL, NULL);
+
+
+    /* since we know we've read all of the PNG file's "header" (i.e., up
+     * to IDAT), we can check for a background color here */
+
+    if (mainprog_ptr->need_bgcolor &&
+        png_get_valid(png_ptr, info_ptr, PNG_INFO_bKGD))
+    {
+        png_color_16p pBackground;
+
+        /* it is not obvious from the libpng documentation, but this function
+         * takes a pointer to a pointer, and it always returns valid red,
+         * green and blue values, regardless of color_type: */
+        png_get_bKGD(png_ptr, info_ptr, &pBackground);
+
+        /* however, it always returns the raw bKGD data, regardless of any
+         * bit-depth transformations, so check depth and adjust if necessary */
+        if (bit_depth == 16) {
+            mainprog_ptr->bg_red   = pBackground->red   >> 8;
+            mainprog_ptr->bg_green = pBackground->green >> 8;
+            mainprog_ptr->bg_blue  = pBackground->blue  >> 8;
+        } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
+            if (bit_depth == 1)
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = pBackground->gray? 255 : 0;
+            else if (bit_depth == 2)
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = (255/3) * pBackground->gray;
+            else /* bit_depth == 4 */
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = (255/15) * pBackground->gray;
+        } else {
+            mainprog_ptr->bg_red   = (uch)pBackground->red;
+            mainprog_ptr->bg_green = (uch)pBackground->green;
+            mainprog_ptr->bg_blue  = (uch)pBackground->blue;
+        }
+    }
+
+
+    /* as before, let libpng expand palette images to RGB, low-bit-depth
+     * grayscale images to 8 bits, transparency chunks to full alpha channel;
+     * strip 16-bit-per-sample images to 8 bits per sample; and convert
+     * grayscale to RGB[A] */
+
+    if (color_type == PNG_COLOR_TYPE_PALETTE)
+        png_set_expand(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+        png_set_expand(png_ptr);
+    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+        png_set_expand(png_ptr);
+    if (bit_depth == 16)
+        png_set_strip_16(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY ||
+        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+        png_set_gray_to_rgb(png_ptr);
+
+
+    /* Unlike the basic viewer, which was designed to operate on local files,
+     * this program is intended to simulate a web browser--even though we
+     * actually read from a local file, too.  But because we are pretending
+     * that most of the images originate on the Internet, we follow the recom-
+     * mendation of the sRGB proposal and treat unlabelled images (no gAMA
+     * chunk) as existing in the sRGB color space.  That is, we assume that
+     * such images have a file gamma of 0.45455, which corresponds to a PC-like
+     * display system.  This change in assumptions will have no effect on a
+     * PC-like system, but on a Mac, SGI, NeXT or other system with a non-
+     * identity lookup table, it will darken unlabelled images, which effec-
+     * tively favors images from PC-like systems over those originating on
+     * the local platform.  Note that mainprog_ptr->display_exponent is the
+     * "gamma" value for the entire display system, i.e., the product of
+     * LUT_exponent and CRT_exponent. */
+
+    if (png_get_gAMA(png_ptr, info_ptr, &gamma))
+        png_set_gamma(png_ptr, mainprog_ptr->display_exponent, gamma);
+    else
+        png_set_gamma(png_ptr, mainprog_ptr->display_exponent, 0.45455);
+
+
+    /* we'll let libpng expand interlaced images, too */
+
+    mainprog_ptr->passes = png_set_interlace_handling(png_ptr);
+
+
+    /* all transformations have been registered; now update info_ptr data and
+     * then get rowbytes and channels */
+
+    png_read_update_info(png_ptr, info_ptr);
+
+    mainprog_ptr->rowbytes = (int)png_get_rowbytes(png_ptr, info_ptr);
+    mainprog_ptr->channels = png_get_channels(png_ptr, info_ptr);
+
+
+    /* Call the main program to allocate memory for the image buffer and
+     * initialize windows and whatnot.  (The old-style function-pointer
+     * invocation is used for compatibility with a few supposedly ANSI
+     * compilers that nevertheless barf on "fn_ptr()"-style syntax.) */
+
+    (*mainprog_ptr->mainprog_init)();
+
+
+    /* and that takes care of initialization */
+
+    return;
+}
+
+
+
+
+
+static void readpng2_row_callback(png_structp png_ptr, png_bytep new_row,
+                                  png_uint_32 row_num, int pass)
+{
+    mainprog_info  *mainprog_ptr;
+
+
+    /* first check whether the row differs from the previous pass; if not,
+     * nothing to combine or display */
+
+    if (!new_row)
+        return;
+
+
+    /* retrieve the pointer to our special-purpose struct so we can access
+     * the old rows and image-display callback function */
+
+    mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+
+    /* save the pass number for optional use by the front end */
+
+    mainprog_ptr->pass = pass;
+
+
+    /* have libpng either combine the new row data with the existing row data
+     * from previous passes (if interlaced) or else just copy the new row
+     * into the main program's image buffer */
+
+    png_progressive_combine_row(png_ptr, mainprog_ptr->row_pointers[row_num],
+      new_row);
+
+
+    /* finally, call the display routine in the main program with the number
+     * of the row we just updated */
+
+    (*mainprog_ptr->mainprog_display_row)(row_num);
+
+
+    /* and we're ready for more */
+
+    return;
+}
+
+
+
+
+
+static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr)
+{
+    mainprog_info  *mainprog_ptr;
+
+
+    /* retrieve the pointer to our special-purpose struct */
+
+    mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+
+    /* let the main program know that it should flush any buffered image
+     * data to the display now and set a "done" flag or whatever, but note
+     * that it SHOULD NOT DESTROY THE PNG STRUCTS YET--in other words, do
+     * NOT call readpng2_cleanup() either here or in the finish_display()
+     * routine; wait until control returns to the main program via
+     * readpng2_decode_data() */
+
+    (*mainprog_ptr->mainprog_finish_display)();
+
+
+    /* all done */
+
+    return;
+}
+
+
+
+
+
+void readpng2_cleanup(mainprog_info *mainprog_ptr)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+    if (png_ptr && info_ptr)
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+
+    mainprog_ptr->png_ptr = NULL;
+    mainprog_ptr->info_ptr = NULL;
+}
+
+
+
+
+
+static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg)
+{
+    mainprog_info  *mainprog_ptr;
+
+    /* This function, aside from the extra step of retrieving the "error
+     * pointer" (below) and the fact that it exists within the application
+     * rather than within libpng, is essentially identical to libpng's
+     * default error handler.  The second point is critical:  since both
+     * setjmp() and longjmp() are called from the same code, they are
+     * guaranteed to have compatible notions of how big a jmp_buf is,
+     * regardless of whether _BSD_SOURCE or anything else has (or has not)
+     * been defined. */
+
+    fprintf(stderr, "readpng2 libpng error: %s\n", msg);
+    fflush(stderr);
+
+    mainprog_ptr = png_get_error_ptr(png_ptr);
+    if (mainprog_ptr == NULL) {         /* we are completely hosed now */
+        fprintf(stderr,
+          "readpng2 severe error:  jmpbuf not recoverable; terminating.\n");
+        fflush(stderr);
+        exit(99);
+    }
+
+    longjmp(mainprog_ptr->jmpbuf, 1);
+}
diff --git a/gs/libpng/contrib/gregbook/readpng2.h b/gs/libpng/contrib/gregbook/readpng2.h
new file mode 100644
index 000000000..7caa9d9cf
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/readpng2.h
@@ -0,0 +1,91 @@
+/*---------------------------------------------------------------------------
+
+   rpng2 - progressive-model PNG display program                 readpng2.h
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2001 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#ifndef TRUE
+#  define TRUE 1
+#  define FALSE 0
+#endif
+
+#ifndef MAX
+#  define MAX(a,b)  ((a) > (b)? (a) : (b))
+#  define MIN(a,b)  ((a) < (b)? (a) : (b))
+#endif
+
+#ifdef DEBUG
+#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}
+#else
+#  define Trace(x)  ;
+#endif
+
+typedef unsigned char   uch;
+typedef unsigned short  ush;
+typedef unsigned long   ulg;
+
+typedef struct _mainprog_info {
+    double display_exponent;
+    ulg width;
+    ulg height;
+    void *png_ptr;
+    void *info_ptr;
+    void (*mainprog_init)(void);
+    void (*mainprog_display_row)(ulg row_num);
+    void (*mainprog_finish_display)(void);
+    uch *image_data;
+    uch **row_pointers;
+    jmp_buf jmpbuf;
+    int passes;              /* not used */
+    int pass;
+    int rowbytes;
+    int channels;
+    int need_bgcolor;
+#if (defined(__i386__) || defined(_M_IX86))
+    int nommxfilters;
+    int nommxcombine;
+    int nommxinterlace;
+#endif
+    int done;
+    uch bg_red;
+    uch bg_green;
+    uch bg_blue;
+} mainprog_info;
+
+
+/* prototypes for public functions in readpng2.c */
+
+void readpng2_version_info(void);
+
+int readpng2_check_sig(uch *sig, int num);
+
+int readpng2_init(mainprog_info *mainprog_ptr);
+
+int readpng2_decode_data(mainprog_info *mainprog_ptr, uch *rawbuf, ulg length);
+
+void readpng2_cleanup(mainprog_info *mainprog_ptr);
diff --git a/gs/libpng/contrib/gregbook/rpng-win.c b/gs/libpng/contrib/gregbook/rpng-win.c
new file mode 100644
index 000000000..b84a7fc21
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/rpng-win.c
@@ -0,0 +1,642 @@
+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                             rpng-win.c
+
+   This program decodes and displays PNG images, with gamma correction and
+   optionally with a user-specified background color (in case the image has
+   transparency).  It is very nearly the most basic PNG viewer possible.
+   This version is for 32-bit Windows; it may compile under 16-bit Windows
+   with a little tweaking (or maybe not).
+
+   to do:
+    - handle quoted command-line args (especially filenames with spaces)
+    - have minimum window width:  oh well
+    - use %.1023s to simplify truncation of title-bar string?
+
+  ---------------------------------------------------------------------------
+
+   Changelog:
+    - 1.00:  initial public release
+    - 1.01:  modified to allow abbreviated options; fixed long/ulong mis-
+              match; switched to png_jmpbuf() macro
+    - 1.02:  added extra set of parentheses to png_jmpbuf() macro; fixed
+              command-line parsing bug
+    - 1.10:  enabled "message window"/console (thanks to David Geldreich)
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2001 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "rpng-win"
+#define LONGNAME  "Simple PNG Viewer for Windows"
+#define VERSION   "1.20 of 28 May 2001"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <windows.h>
+#include <conio.h>      /* only for _getch() */
+
+/* #define DEBUG  :  this enables the Trace() macros */
+
+#include "readpng.h"    /* typedefs, common macros, readpng prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects
+ * only happen with alpha (which could easily be avoided with
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) {               \
+    ush temp = ((ush)(fg)*(ush)(alpha) +                          \
+                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \
+    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \
+}
+
+
+/* local prototypes */
+static int        rpng_win_create_window(HINSTANCE hInst, int showmode);
+static int        rpng_win_display_image(void);
+static void       rpng_win_cleanup(void);
+LRESULT CALLBACK  rpng_win_wndproc(HWND, UINT, WPARAM, LPARAM);
+
+
+static char titlebar[1024], *window_name = titlebar;
+static char *progname = PROGNAME;
+static char *appname = LONGNAME;
+static char *icon_name = PROGNAME;     /* GRR:  not (yet) used */
+static char *filename;
+static FILE *infile;
+
+static char *bgstr;
+static uch bg_red=0, bg_green=0, bg_blue=0;
+
+static double display_exponent;
+
+static ulg image_width, image_height, image_rowbytes;
+static int image_channels;
+static uch *image_data;
+
+/* Windows-specific variables */
+static ulg wimage_rowbytes;
+static uch *dib;
+static uch *wimage_data;
+static BITMAPINFOHEADER *bmih;
+
+static HWND global_hwnd;
+
+
+
+
+int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
+{
+    char *args[1024];                 /* arbitrary limit, but should suffice */
+    char *p, *q, **argv = args;
+    int argc = 0;
+    int rc, alen, flen;
+    int error = 0;
+    int have_bg = FALSE;
+    double LUT_exponent;              /* just the lookup table */
+    double CRT_exponent = 2.2;        /* just the monitor */
+    double default_display_exponent;  /* whole display system */
+    MSG msg;
+
+
+    filename = (char *)NULL;
+
+
+    /* First reenable console output, which normally goes to the bit bucket
+     * for windowed apps.  Closing the console window will terminate the
+     * app.  Thanks to David.Geldreich@realviz.com for supplying the magical
+     * incantation. */
+
+    AllocConsole();
+    freopen("CONOUT$", "a", stderr);
+    freopen("CONOUT$", "a", stdout);
+
+
+    /* Next set the default value for our display-system exponent, i.e.,
+     * the product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  This is not an
+     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+     * ones), but it should cover 99% of the current possibilities.  And
+     * yes, these ifdefs are completely wasted in a Windows program... */
+
+#if defined(NeXT)
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to get the
+     * "gamma" value, so we do it the hard way */
+    infile = fopen("/etc/config/system.glGammaVal", "r");
+    if (infile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, infile);
+        fclose(infile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL)
+        display_exponent = atof(p);
+    else
+        display_exponent = default_display_exponent;
+
+
+    /* Windows really hates command lines, so we have to set up our own argv.
+     * Note that we do NOT bother with quoted arguments here, so don't use
+     * filenames with spaces in 'em! */
+
+    argv[argc++] = PROGNAME;
+    p = cmd;
+    for (;;) {
+        if (*p == ' ')
+            while (*++p == ' ')
+                ;
+        /* now p points at the first non-space after some spaces */
+        if (*p == '\0')
+            break;    /* nothing after the spaces:  done */
+        argv[argc++] = q = p;
+        while (*q && *q != ' ')
+            ++q;
+        /* now q points at a space or the end of the string */
+        if (*q == '\0')
+            break;    /* last argv already terminated; quit */
+        *q = '\0';    /* change space to terminator */
+        p = q + 1;
+    }
+    argv[argc] = NULL;   /* terminate the argv array itself */
+
+
+    /* Now parse the command line for options and the PNG filename. */
+
+    while (*++argv && !error) {
+        if (!strncmp(*argv, "-gamma", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                display_exponent = atof(*argv);
+                if (display_exponent <= 0.0)
+                    ++error;
+            }
+        } else if (!strncmp(*argv, "-bgcolor", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                bgstr = *argv;
+                if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                    ++error;
+                else
+                    have_bg = TRUE;
+            }
+        } else {
+            if (**argv != '-') {
+                filename = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+    if (!filename) {
+        ++error;
+    } else if (!(infile = fopen(filename, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
+        ++error;
+    } else {
+        if ((rc = readpng_init(infile, &image_width, &image_height)) != 0) {
+            switch (rc) {
+                case 1:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] is not a PNG file: incorrect signature\n",
+                      filename);
+                    break;
+                case 2:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] has bad IHDR (libpng longjmp)\n",
+                      filename);
+                    break;
+                case 4:
+                    fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                    break;
+                default:
+                    fprintf(stderr, PROGNAME
+                      ":  unknown readpng_init() error\n");
+                    break;
+            }
+            ++error;
+        }
+        if (error)
+            fclose(infile);
+    }
+
+
+    /* usage screen */
+
+    if (error) {
+        int ch;
+
+        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);
+        readpng_version_info();
+        fprintf(stderr, "\n"
+          "Usage:  %s [-gamma exp] [-bgcolor bg] file.png\n"
+          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+          "\t\t  to the product of the lookup-table exponent (varies)\n"
+          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+          "    bg  \tdesired background color in 7-character hex RGB format\n"
+          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
+          "\t\t  used with transparent images\n"
+          "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
+          "Press Q or Esc to quit this usage screen.\n"
+          "\n", PROGNAME, default_display_exponent);
+        do
+            ch = _getch();
+        while (ch != 'q' && ch != 'Q' && ch != 0x1B);
+        exit(1);
+    } else {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
+        fprintf(stderr,
+          "\n   [console window:  closing this window will terminate %s]\n\n",
+          PROGNAME);
+    }
+
+
+    /* set the title-bar string, but make sure buffer doesn't overflow */
+
+    alen = strlen(appname);
+    flen = strlen(filename);
+    if (alen + flen + 3 > 1023)
+        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));
+    else
+        sprintf(titlebar, "%s:  %s", appname, filename);
+
+
+    /* if the user didn't specify a background color on the command line,
+     * check for one in the PNG file--if not, the initialized values of 0
+     * (black) will be used */
+
+    if (have_bg)
+        sscanf(bgstr+1, "%2x%2x%2x", &bg_red, &bg_green, &bg_blue);
+    else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) {
+        readpng_cleanup(TRUE);
+        fprintf(stderr, PROGNAME
+          ":  libpng error while checking for background color\n");
+        exit(2);
+    }
+
+
+    /* do the basic Windows initialization stuff, make the window and fill it
+     * with the background color */
+
+    if (rpng_win_create_window(hInst, showmode))
+        exit(2);
+
+
+    /* decode the image, all at once */
+
+    Trace((stderr, "calling readpng_get_image()\n"))
+    image_data = readpng_get_image(display_exponent, &image_channels,
+      &image_rowbytes);
+    Trace((stderr, "done with readpng_get_image()\n"))
+
+
+    /* done with PNG file, so clean up to minimize memory usage (but do NOT
+     * nuke image_data!) */
+
+    readpng_cleanup(FALSE);
+    fclose(infile);
+
+    if (!image_data) {
+        fprintf(stderr, PROGNAME ":  unable to decode PNG image\n");
+        exit(3);
+    }
+
+
+    /* display image (composite with background if requested) */
+
+    Trace((stderr, "calling rpng_win_display_image()\n"))
+    if (rpng_win_display_image()) {
+        free(image_data);
+        exit(4);
+    }
+    Trace((stderr, "done with rpng_win_display_image()\n"))
+
+
+    /* wait for the user to tell us when to quit */
+
+    printf(
+      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n");
+    fflush(stdout);
+
+    while (GetMessage(&msg, NULL, 0, 0)) {
+        TranslateMessage(&msg);
+        DispatchMessage(&msg);
+    }
+
+
+    /* OK, we're done:  clean up all image and Windows resources and go away */
+
+    rpng_win_cleanup();
+
+    return msg.wParam;
+}
+
+
+
+
+
+static int rpng_win_create_window(HINSTANCE hInst, int showmode)
+{
+    uch *dest;
+    int extra_width, extra_height;
+    ulg i, j;
+    WNDCLASSEX wndclass;
+
+
+/*---------------------------------------------------------------------------
+    Allocate memory for the display-specific version of the image (round up
+    to multiple of 4 for Windows DIB).
+  ---------------------------------------------------------------------------*/
+
+    wimage_rowbytes = ((3*image_width + 3L) >> 2) << 2;
+
+    if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) +
+                              wimage_rowbytes*image_height)))
+    {
+        return 4;   /* fail */
+    }
+
+/*---------------------------------------------------------------------------
+    Initialize the DIB.  Negative height means to use top-down BMP ordering
+    (must be uncompressed, but that's what we want).  Bit count of 1, 4 or 8
+    implies a colormap of RGBX quads, but 24-bit BMPs just use B,G,R values
+    directly => wimage_data begins immediately after BMP header.
+  ---------------------------------------------------------------------------*/
+
+    memset(dib, 0, sizeof(BITMAPINFOHEADER));
+    bmih = (BITMAPINFOHEADER *)dib;
+    bmih->biSize = sizeof(BITMAPINFOHEADER);
+    bmih->biWidth = image_width;
+    bmih->biHeight = -((long)image_height);
+    bmih->biPlanes = 1;
+    bmih->biBitCount = 24;
+    bmih->biCompression = 0;
+    wimage_data = dib + sizeof(BITMAPINFOHEADER);
+
+/*---------------------------------------------------------------------------
+    Fill in background color (black by default); data are in BGR order.
+  ---------------------------------------------------------------------------*/
+
+    for (j = 0;  j < image_height;  ++j) {
+        dest = wimage_data + j*wimage_rowbytes;
+        for (i = image_width;  i > 0;  --i) {
+            *dest++ = bg_blue;
+            *dest++ = bg_green;
+            *dest++ = bg_red;
+        }
+    }
+
+/*---------------------------------------------------------------------------
+    Set the window parameters.
+  ---------------------------------------------------------------------------*/
+
+    memset(&wndclass, 0, sizeof(wndclass));
+
+    wndclass.cbSize = sizeof(wndclass);
+    wndclass.style = CS_HREDRAW | CS_VREDRAW;
+    wndclass.lpfnWndProc = rpng_win_wndproc;
+    wndclass.hInstance = hInst;
+    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
+    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
+    wndclass.hbrBackground = (HBRUSH)GetStockObject(DKGRAY_BRUSH);
+    wndclass.lpszMenuName = NULL;
+    wndclass.lpszClassName = progname;
+    wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
+
+    RegisterClassEx(&wndclass);
+
+/*---------------------------------------------------------------------------
+    Finally, create the window.
+  ---------------------------------------------------------------------------*/
+
+    extra_width  = 2*(GetSystemMetrics(SM_CXBORDER) +
+                      GetSystemMetrics(SM_CXDLGFRAME));
+    extra_height = 2*(GetSystemMetrics(SM_CYBORDER) +
+                      GetSystemMetrics(SM_CYDLGFRAME)) +
+                      GetSystemMetrics(SM_CYCAPTION);
+
+    global_hwnd = CreateWindow(progname, titlebar, WS_OVERLAPPEDWINDOW,
+      CW_USEDEFAULT, CW_USEDEFAULT, image_width+extra_width,
+      image_height+extra_height, NULL, NULL, hInst, NULL);
+
+    ShowWindow(global_hwnd, showmode);
+    UpdateWindow(global_hwnd);
+
+    return 0;
+
+} /* end function rpng_win_create_window() */
+
+
+
+
+
+static int rpng_win_display_image()
+{
+    uch *src, *dest;
+    uch r, g, b, a;
+    ulg i, row, lastrow;
+    RECT rect;
+
+
+    Trace((stderr, "beginning display loop (image_channels == %d)\n",
+      image_channels))
+    Trace((stderr, "(width = %ld, rowbytes = %ld, wimage_rowbytes = %d)\n",
+      image_width, image_rowbytes, wimage_rowbytes))
+
+
+/*---------------------------------------------------------------------------
+    Blast image data to buffer.  This whole routine takes place before the
+    message loop begins, so there's no real point in any pseudo-progressive
+    display...
+  ---------------------------------------------------------------------------*/
+
+    for (lastrow = row = 0;  row < image_height;  ++row) {
+        src = image_data + row*image_rowbytes;
+        dest = wimage_data + row*wimage_rowbytes;
+        if (image_channels == 3) {
+            for (i = image_width;  i > 0;  --i) {
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                *dest++ = b;
+                *dest++ = g;   /* note reverse order */
+                *dest++ = r;
+            }
+        } else /* if (image_channels == 4) */ {
+            for (i = image_width;  i > 0;  --i) {
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                a = *src++;
+                if (a == 255) {
+                    *dest++ = b;
+                    *dest++ = g;
+                    *dest++ = r;
+                } else if (a == 0) {
+                    *dest++ = bg_blue;
+                    *dest++ = bg_green;
+                    *dest++ = bg_red;
+                } else {
+                    /* this macro (copied from png.h) composites the
+                     * foreground and background values and puts the
+                     * result into the first argument; there are no
+                     * side effects with the first argument */
+                    alpha_composite(*dest++, b, a, bg_blue);
+                    alpha_composite(*dest++, g, a, bg_green);
+                    alpha_composite(*dest++, r, a, bg_red);
+                }
+            }
+        }
+        /* display after every 16 lines */
+        if (((row+1) & 0xf) == 0) {
+            rect.left = 0L;
+            rect.top = (LONG)lastrow;
+            rect.right = (LONG)image_width;      /* possibly off by one? */
+            rect.bottom = (LONG)lastrow + 16L;   /* possibly off by one? */
+            InvalidateRect(global_hwnd, &rect, FALSE);
+            UpdateWindow(global_hwnd);     /* similar to XFlush() */
+            lastrow = row + 1;
+        }
+    }
+
+    Trace((stderr, "calling final image-flush routine\n"))
+    if (lastrow < image_height) {
+        rect.left = 0L;
+        rect.top = (LONG)lastrow;
+        rect.right = (LONG)image_width;      /* possibly off by one? */
+        rect.bottom = (LONG)image_height;    /* possibly off by one? */
+        InvalidateRect(global_hwnd, &rect, FALSE);
+        UpdateWindow(global_hwnd);     /* similar to XFlush() */
+    }
+
+/*
+    last param determines whether or not background is wiped before paint
+    InvalidateRect(global_hwnd, NULL, TRUE);
+    UpdateWindow(global_hwnd);
+ */
+
+    return 0;
+}
+
+
+
+
+
+static void rpng_win_cleanup()
+{
+    if (image_data) {
+        free(image_data);
+        image_data = NULL;
+    }
+
+    if (dib) {
+        free(dib);
+        dib = NULL;
+    }
+}
+
+
+
+
+
+LRESULT CALLBACK rpng_win_wndproc(HWND hwnd, UINT iMsg, WPARAM wP, LPARAM lP)
+{
+    HDC         hdc;
+    PAINTSTRUCT ps;
+    int rc;
+
+    switch (iMsg) {
+        case WM_CREATE:
+            /* one-time processing here, if any */
+            return 0;
+
+        case WM_PAINT:
+            hdc = BeginPaint(hwnd, &ps);
+                    /*                    dest                          */
+            rc = StretchDIBits(hdc, 0, 0, image_width, image_height,
+                    /*                    source                        */
+                                    0, 0, image_width, image_height,
+                                    wimage_data, (BITMAPINFO *)bmih,
+                    /*              iUsage: no clue                     */
+                                    0, SRCCOPY);
+            EndPaint(hwnd, &ps);
+            return 0;
+
+        /* wait for the user to tell us when to quit */
+        case WM_CHAR:
+            switch (wP) {      /* only need one, so ignore repeat count */
+                case 'q':
+                case 'Q':
+                case 0x1B:     /* Esc key */
+                    PostQuitMessage(0);
+            }
+            return 0;
+
+        case WM_LBUTTONDOWN:   /* another way of quitting */
+        case WM_DESTROY:
+            PostQuitMessage(0);
+            return 0;
+    }
+
+    return DefWindowProc(hwnd, iMsg, wP, lP);
+}
diff --git a/gs/libpng/contrib/gregbook/rpng-x.c b/gs/libpng/contrib/gregbook/rpng-x.c
new file mode 100644
index 000000000..e787ef1d5
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/rpng-x.c
@@ -0,0 +1,858 @@
+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                               rpng-x.c
+
+   This program decodes and displays PNG images, with gamma correction and
+   optionally with a user-specified background color (in case the image has
+   transparency).  It is very nearly the most basic PNG viewer possible.
+   This version is for the X Window System (tested by author under Unix and
+   by Martin Zinser under OpenVMS; may work under OS/2 with some tweaking).
+
+   to do:
+    - 8-bit support
+    - use %.1023s to simplify truncation of title-bar string?
+
+  ---------------------------------------------------------------------------
+
+   Changelog:
+    - 1.01:  initial public release
+    - 1.02:  modified to allow abbreviated options; fixed long/ulong mis-
+              match; switched to png_jmpbuf() macro
+    - 1.10:  added support for non-default visuals; fixed X pixel-conversion
+    - 1.11:  added extra set of parentheses to png_jmpbuf() macro; fixed
+              command-line parsing bug
+    - 1.12:  fixed small X memory leak (thanks to Francois Petitjean)
+    - 1.13:  fixed XFreeGC() crash bug
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2001 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "rpng-x"
+#define LONGNAME  "Simple PNG Viewer for X"
+#define VERSION   "1.13 of 16 August 2001"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <X11/Xos.h>
+#include <X11/keysym.h>
+
+/* #define DEBUG  :  this enables the Trace() macros */
+
+#include "readpng.h"   /* typedefs, common macros, readpng prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects
+ * only happen with alpha (which could easily be avoided with
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) {               \
+    ush temp = ((ush)(fg)*(ush)(alpha) +                          \
+                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \
+    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \
+}
+
+
+/* local prototypes */
+static int  rpng_x_create_window(void);
+static int  rpng_x_display_image(void);
+static void rpng_x_cleanup(void);
+static int  rpng_x_msb(ulg u32val);
+
+
+static char titlebar[1024], *window_name = titlebar;
+static char *appname = LONGNAME;
+static char *icon_name = PROGNAME;
+static char *filename;
+static FILE *infile;
+
+static char *bgstr;
+static uch bg_red=0, bg_green=0, bg_blue=0;
+
+static double display_exponent;
+
+static ulg image_width, image_height, image_rowbytes;
+static int image_channels;
+static uch *image_data;
+
+/* X-specific variables */
+static char *displayname;
+static XImage *ximage;
+static Display *display;
+static int depth;
+static Visual *visual;
+static XVisualInfo *visual_list;
+static int RShift, GShift, BShift;
+static ulg RMask, GMask, BMask;
+static Window window;
+static GC gc;
+static Colormap colormap;
+
+static int have_nondefault_visual = FALSE;
+static int have_colormap = FALSE;
+static int have_window = FALSE;
+static int have_gc = FALSE;
+/*
+ulg numcolors=0, pixels[256];
+ush reds[256], greens[256], blues[256];
+ */
+
+
+
+
+int main(int argc, char **argv)
+{
+#ifdef sgi
+    char tmpline[80];
+#endif
+    char *p;
+    int rc, alen, flen;
+    int error = 0;
+    int have_bg = FALSE;
+    double LUT_exponent;               /* just the lookup table */
+    double CRT_exponent = 2.2;         /* just the monitor */
+    double default_display_exponent;   /* whole display system */
+    XEvent e;
+    KeySym k;
+
+
+    displayname = (char *)NULL;
+    filename = (char *)NULL;
+
+
+    /* First set the default value for our display-system exponent, i.e.,
+     * the product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  This is not an
+     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+     * ones), but it should cover 99% of the current possibilities. */
+
+#if defined(NeXT)
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to get the
+     * "gamma" value, so we do it the hard way */
+    infile = fopen("/etc/config/system.glGammaVal", "r");
+    if (infile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, infile);
+        fclose(infile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL)
+        display_exponent = atof(p);
+    else
+        display_exponent = default_display_exponent;
+
+
+    /* Now parse the command line for options and the PNG filename. */
+
+    while (*++argv && !error) {
+        if (!strncmp(*argv, "-display", 2)) {
+            if (!*++argv)
+                ++error;
+            else
+                displayname = *argv;
+        } else if (!strncmp(*argv, "-gamma", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                display_exponent = atof(*argv);
+                if (display_exponent <= 0.0)
+                    ++error;
+            }
+        } else if (!strncmp(*argv, "-bgcolor", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                bgstr = *argv;
+                if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                    ++error; 
+                else 
+                    have_bg = TRUE;
+            }
+        } else {
+            if (**argv != '-') {
+                filename = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+    if (!filename) {
+        ++error;
+    } else if (!(infile = fopen(filename, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
+        ++error;
+    } else {
+        if ((rc = readpng_init(infile, &image_width, &image_height)) != 0) {
+            switch (rc) {
+                case 1:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] is not a PNG file: incorrect signature\n",
+                      filename);
+                    break;
+                case 2:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] has bad IHDR (libpng longjmp)\n",
+                      filename);
+                    break;
+                case 4:
+                    fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                    break;
+                default:
+                    fprintf(stderr, PROGNAME
+                      ":  unknown readpng_init() error\n");
+                    break;
+            }
+            ++error;
+        } else {
+            display = XOpenDisplay(displayname);
+            if (!display) {
+                readpng_cleanup(TRUE);
+                fprintf(stderr, PROGNAME ":  can't open X display [%s]\n",
+                  displayname? displayname : "default");
+                ++error;
+            }
+        }
+        if (error)
+            fclose(infile);
+    }
+
+
+    /* usage screen */
+
+    if (error) {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
+        readpng_version_info();
+        fprintf(stderr, "\n"
+          "Usage:  %s [-display xdpy] [-gamma exp] [-bgcolor bg] file.png\n"
+          "    xdpy\tname of the target X display (e.g., ``hostname:0'')\n"
+          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+          "\t\t  to the product of the lookup-table exponent (varies)\n"
+          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+          "    bg  \tdesired background color in 7-character hex RGB format\n"
+          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
+          "\t\t  used with transparent images\n"
+          "\nPress Q, Esc or mouse button 1 (within image window, after image\n"
+          "is displayed) to quit.\n"
+          "\n", PROGNAME, default_display_exponent);
+        exit(1);
+    }
+
+
+    /* set the title-bar string, but make sure buffer doesn't overflow */
+
+    alen = strlen(appname);
+    flen = strlen(filename);
+    if (alen + flen + 3 > 1023)
+        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));
+    else
+        sprintf(titlebar, "%s:  %s", appname, filename);
+
+
+    /* if the user didn't specify a background color on the command line,
+     * check for one in the PNG file--if not, the initialized values of 0
+     * (black) will be used */
+
+    if (have_bg) {
+        unsigned r, g, b;   /* this approach quiets compiler warnings */
+
+        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+        bg_red   = (uch)r;
+        bg_green = (uch)g;
+        bg_blue  = (uch)b;
+    } else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) {
+        readpng_cleanup(TRUE);
+        fprintf(stderr, PROGNAME
+          ":  libpng error while checking for background color\n");
+        exit(2);
+    }
+
+
+    /* do the basic X initialization stuff, make the window and fill it
+     * with the background color */
+
+    if (rpng_x_create_window())
+        exit(2);
+
+
+    /* decode the image, all at once */
+
+    Trace((stderr, "calling readpng_get_image()\n"))
+    image_data = readpng_get_image(display_exponent, &image_channels,
+      &image_rowbytes);
+    Trace((stderr, "done with readpng_get_image()\n"))
+
+
+    /* done with PNG file, so clean up to minimize memory usage (but do NOT
+     * nuke image_data!) */
+
+    readpng_cleanup(FALSE);
+    fclose(infile);
+
+    if (!image_data) {
+        fprintf(stderr, PROGNAME ":  unable to decode PNG image\n");
+        exit(3);
+    }
+
+
+    /* display image (composite with background if requested) */
+
+    Trace((stderr, "calling rpng_x_display_image()\n"))
+    if (rpng_x_display_image()) {
+        free(image_data);
+        exit(4);
+    }
+    Trace((stderr, "done with rpng_x_display_image()\n"))
+
+
+    /* wait for the user to tell us when to quit */
+
+    printf(
+      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n");
+    fflush(stdout);
+
+    do
+        XNextEvent(display, &e);
+    while (!(e.type == ButtonPress && e.xbutton.button == Button1) &&
+           !(e.type == KeyPress &&    /*  v--- or 1 for shifted keys */
+             ((k = XLookupKeysym(&e.xkey, 0)) == XK_q || k == XK_Escape) ));
+
+
+    /* OK, we're done:  clean up all image and X resources and go away */
+
+    rpng_x_cleanup();
+
+    return 0;
+}
+
+
+
+
+
+static int rpng_x_create_window(void)
+{
+    uch *xdata;
+    int need_colormap = FALSE;
+    int screen, pad;
+    ulg bg_pixel = 0L;
+    ulg attrmask;
+    Window root;
+    XEvent e;
+    XGCValues gcvalues;
+    XSetWindowAttributes attr;
+    XSizeHints *size_hints;
+    XTextProperty windowName, *pWindowName = &windowName;
+    XTextProperty iconName, *pIconName = &iconName;
+    XVisualInfo visual_info;
+    XWMHints *wm_hints;
+
+
+    screen = DefaultScreen(display);
+    depth = DisplayPlanes(display, screen);
+    root = RootWindow(display, screen);
+
+#ifdef DEBUG
+    XSynchronize(display, True);
+#endif
+
+#if 0
+/* GRR:  add 8-bit support */
+    if (/* depth != 8 && */ depth != 16 && depth != 24 && depth != 32) {
+        fprintf(stderr,
+          "screen depth %d not supported (only 16-, 24- or 32-bit TrueColor)\n",
+          depth);
+        return 2;
+    }
+
+    XMatchVisualInfo(display, screen, depth,
+      (depth == 8)? PseudoColor : TrueColor, &visual_info);
+    visual = visual_info.visual;
+#else
+    if (depth != 16 && depth != 24 && depth != 32) {
+        int visuals_matched = 0;
+
+        Trace((stderr, "default depth is %d:  checking other visuals\n",
+          depth))
+
+        /* 24-bit first */
+        visual_info.screen = screen;
+        visual_info.depth = 24;
+        visual_list = XGetVisualInfo(display,
+          VisualScreenMask | VisualDepthMask, &visual_info, &visuals_matched);
+        if (visuals_matched == 0) {
+/* GRR:  add 15-, 16- and 32-bit TrueColor visuals (also DirectColor?) */
+            fprintf(stderr, "default screen depth %d not supported, and no"
+              " 24-bit visuals found\n", depth);
+            return 2;
+        }
+        Trace((stderr, "XGetVisualInfo() returned %d 24-bit visuals\n",
+          visuals_matched))
+        visual = visual_list[0].visual;
+        depth = visual_list[0].depth;
+/*
+        colormap_size = visual_list[0].colormap_size;
+        visual_class = visual->class;
+        visualID = XVisualIDFromVisual(visual);
+ */
+        have_nondefault_visual = TRUE;
+        need_colormap = TRUE;
+    } else {
+        XMatchVisualInfo(display, screen, depth, TrueColor, &visual_info);
+        visual = visual_info.visual;
+    }
+#endif
+
+    RMask = visual->red_mask;
+    GMask = visual->green_mask;
+    BMask = visual->blue_mask;
+
+/* GRR:  add/check 8-bit support */
+    if (depth == 8 || need_colormap) {
+        colormap = XCreateColormap(display, root, visual, AllocNone);
+        if (!colormap) {
+            fprintf(stderr, "XCreateColormap() failed\n");
+            return 2;
+        }
+        have_colormap = TRUE;
+    }
+    if (depth == 15 || depth == 16) {
+        RShift = 15 - rpng_x_msb(RMask);    /* these are right-shifts */
+        GShift = 15 - rpng_x_msb(GMask);
+        BShift = 15 - rpng_x_msb(BMask);
+    } else if (depth > 16) {
+#define NO_24BIT_MASKS
+#ifdef NO_24BIT_MASKS
+        RShift = rpng_x_msb(RMask) - 7;     /* these are left-shifts */
+        GShift = rpng_x_msb(GMask) - 7;
+        BShift = rpng_x_msb(BMask) - 7;
+#else
+        RShift = 7 - rpng_x_msb(RMask);     /* these are right-shifts, too */
+        GShift = 7 - rpng_x_msb(GMask);
+        BShift = 7 - rpng_x_msb(BMask);
+#endif
+    }
+    if (depth >= 15 && (RShift < 0 || GShift < 0 || BShift < 0)) {
+        fprintf(stderr, "rpng internal logic error:  negative X shift(s)!\n");
+        return 2;
+    }
+
+/*---------------------------------------------------------------------------
+    Finally, create the window.
+  ---------------------------------------------------------------------------*/
+
+    attr.backing_store = Always;
+    attr.event_mask = ExposureMask | KeyPressMask | ButtonPressMask;
+    attrmask = CWBackingStore | CWEventMask;
+    if (have_nondefault_visual) {
+        attr.colormap = colormap;
+        attr.background_pixel = 0;
+        attr.border_pixel = 1;
+        attrmask |= CWColormap | CWBackPixel | CWBorderPixel;
+    }
+
+    window = XCreateWindow(display, root, 0, 0, image_width, image_height, 0,
+      depth, InputOutput, visual, attrmask, &attr);
+
+    if (window == None) {
+        fprintf(stderr, "XCreateWindow() failed\n");
+        return 2;
+    } else
+        have_window = TRUE;
+
+    if (depth == 8)
+        XSetWindowColormap(display, window, colormap);
+
+    if (!XStringListToTextProperty(&window_name, 1, pWindowName))
+        pWindowName = NULL;
+    if (!XStringListToTextProperty(&icon_name, 1, pIconName))
+        pIconName = NULL;
+
+    /* OK if either hints allocation fails; XSetWMProperties() allows NULLs */
+
+    if ((size_hints = XAllocSizeHints()) != NULL) {
+        /* window will not be resizable */
+        size_hints->flags = PMinSize | PMaxSize;
+        size_hints->min_width = size_hints->max_width = (int)image_width;
+        size_hints->min_height = size_hints->max_height = (int)image_height;
+    }
+
+    if ((wm_hints = XAllocWMHints()) != NULL) {
+        wm_hints->initial_state = NormalState;
+        wm_hints->input = True;
+     /* wm_hints->icon_pixmap = icon_pixmap; */
+        wm_hints->flags = StateHint | InputHint  /* | IconPixmapHint */ ;
+    }
+
+    XSetWMProperties(display, window, pWindowName, pIconName, NULL, 0,
+      size_hints, wm_hints, NULL);
+
+    /* various properties and hints no longer needed; free memory */
+    if (pWindowName)
+       XFree(pWindowName->value);
+    if (pIconName)
+       XFree(pIconName->value);
+    if (size_hints)
+        XFree(size_hints);
+    if (wm_hints)
+       XFree(wm_hints);
+
+    XMapWindow(display, window);
+
+    gc = XCreateGC(display, window, 0, &gcvalues);
+    have_gc = TRUE;
+
+/*---------------------------------------------------------------------------
+    Fill window with the specified background color.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        bg_pixel = ((ulg)bg_red   << RShift) |
+                   ((ulg)bg_green << GShift) |
+                   ((ulg)bg_blue  << BShift);
+    } else if (depth == 16) {
+        bg_pixel = ((((ulg)bg_red   << 8) >> RShift) & RMask) |
+                   ((((ulg)bg_green << 8) >> GShift) & GMask) |
+                   ((((ulg)bg_blue  << 8) >> BShift) & BMask);
+    } else /* depth == 8 */ {
+
+        /* GRR:  add 8-bit support */
+
+    }
+
+    XSetForeground(display, gc, bg_pixel);
+    XFillRectangle(display, window, gc, 0, 0, image_width, image_height);
+
+/*---------------------------------------------------------------------------
+    Wait for first Expose event to do any drawing, then flush.
+  ---------------------------------------------------------------------------*/
+
+    do
+        XNextEvent(display, &e);
+    while (e.type != Expose || e.xexpose.count);
+
+    XFlush(display);
+
+/*---------------------------------------------------------------------------
+    Allocate memory for the X- and display-specific version of the image.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        xdata = (uch *)malloc(4*image_width*image_height);
+        pad = 32;
+    } else if (depth == 16) {
+        xdata = (uch *)malloc(2*image_width*image_height);
+        pad = 16;
+    } else /* depth == 8 */ {
+        xdata = (uch *)malloc(image_width*image_height);
+        pad = 8;
+    }
+
+    if (!xdata) {
+        fprintf(stderr, PROGNAME ":  unable to allocate image memory\n");
+        return 4;
+    }
+
+    ximage = XCreateImage(display, visual, depth, ZPixmap, 0,
+      (char *)xdata, image_width, image_height, pad, 0);
+
+    if (!ximage) {
+        fprintf(stderr, PROGNAME ":  XCreateImage() failed\n");
+        free(xdata);
+        return 3;
+    }
+
+    /* to avoid testing the byte order every pixel (or doubling the size of
+     * the drawing routine with a giant if-test), we arbitrarily set the byte
+     * order to MSBFirst and let Xlib worry about inverting things on little-
+     * endian machines (like Linux/x86, old VAXen, etc.)--this is not the most
+     * efficient approach (the giant if-test would be better), but in the
+     * interest of clarity, we take the easy way out... */
+
+    ximage->byte_order = MSBFirst;
+
+    return 0;
+
+} /* end function rpng_x_create_window() */
+
+
+
+
+
+static int rpng_x_display_image(void)
+{
+    uch *src;
+    char *dest;
+    uch r, g, b, a;
+    ulg i, row, lastrow = 0;
+    ulg pixel;
+    int ximage_rowbytes = ximage->bytes_per_line;
+/*  int bpp = ximage->bits_per_pixel;  */
+
+
+    Trace((stderr, "beginning display loop (image_channels == %d)\n",
+      image_channels))
+    Trace((stderr, "   (width = %ld, rowbytes = %ld, ximage_rowbytes = %d)\n",
+      image_width, image_rowbytes, ximage_rowbytes))
+    Trace((stderr, "   (bpp = %d)\n", ximage->bits_per_pixel))
+    Trace((stderr, "   (byte_order = %s)\n", ximage->byte_order == MSBFirst?
+      "MSBFirst" : (ximage->byte_order == LSBFirst? "LSBFirst" : "unknown")))
+
+    if (depth == 24 || depth == 32) {
+        ulg red, green, blue;
+
+        for (lastrow = row = 0;  row < image_height;  ++row) {
+            src = image_data + row*image_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            if (image_channels == 3) {
+                for (i = image_width;  i > 0;  --i) {
+                    red   = *src++;
+                    green = *src++;
+                    blue  = *src++;
+#ifdef NO_24BIT_MASKS
+                    pixel = (red   << RShift) |
+                            (green << GShift) |
+                            (blue  << BShift);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    /* GRR BUG:  this assumes bpp == 32, but may be 24: */
+                    *dest++ = (char)((pixel >> 24) & 0xff);
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+#else
+                    red   = (RShift < 0)? red   << (-RShift) : red   >> RShift;
+                    green = (GShift < 0)? green << (-GShift) : green >> GShift;
+                    blue  = (BShift < 0)? blue  << (-BShift) : blue  >> BShift;
+                    pixel = (red & RMask) | (green & GMask) | (blue & BMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = (char)((pixel >> 24) & 0xff);
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+#endif
+                }
+            } else /* if (image_channels == 4) */ {
+                for (i = image_width;  i > 0;  --i) {
+                    r = *src++;
+                    g = *src++;
+                    b = *src++;
+                    a = *src++;
+                    if (a == 255) {
+                        red   = r;
+                        green = g;
+                        blue  = b;
+                    } else if (a == 0) {
+                        red   = bg_red;
+                        green = bg_green;
+                        blue  = bg_blue;
+                    } else {
+                        /* this macro (from png.h) composites the foreground
+                         * and background values and puts the result into the
+                         * first argument */
+                        alpha_composite(red,   r, a, bg_red);
+                        alpha_composite(green, g, a, bg_green);
+                        alpha_composite(blue,  b, a, bg_blue);
+                    }
+                    pixel = (red   << RShift) |
+                            (green << GShift) |
+                            (blue  << BShift);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = (char)((pixel >> 24) & 0xff);
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            }
+            /* display after every 16 lines */
+            if (((row+1) & 0xf) == 0) {
+                XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,
+                  (int)lastrow, image_width, 16);
+                XFlush(display);
+                lastrow = row + 1;
+            }
+        }
+
+    } else if (depth == 16) {
+        ush red, green, blue;
+
+        for (lastrow = row = 0;  row < image_height;  ++row) {
+            src = image_data + row*image_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            if (image_channels == 3) {
+                for (i = image_width;  i > 0;  --i) {
+                    red   = ((ush)(*src) << 8);
+                    ++src;
+                    green = ((ush)(*src) << 8);
+                    ++src;
+                    blue  = ((ush)(*src) << 8);
+                    ++src;
+                    pixel = ((red   >> RShift) & RMask) |
+                            ((green >> GShift) & GMask) |
+                            ((blue  >> BShift) & BMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            } else /* if (image_channels == 4) */ {
+                for (i = image_width;  i > 0;  --i) {
+                    r = *src++;
+                    g = *src++;
+                    b = *src++;
+                    a = *src++;
+                    if (a == 255) {
+                        red   = ((ush)r << 8);
+                        green = ((ush)g << 8);
+                        blue  = ((ush)b << 8);
+                    } else if (a == 0) {
+                        red   = ((ush)bg_red   << 8);
+                        green = ((ush)bg_green << 8);
+                        blue  = ((ush)bg_blue  << 8);
+                    } else {
+                        /* this macro (from png.h) composites the foreground
+                         * and background values and puts the result back into
+                         * the first argument (== fg byte here:  safe) */
+                        alpha_composite(r, r, a, bg_red);
+                        alpha_composite(g, g, a, bg_green);
+                        alpha_composite(b, b, a, bg_blue);
+                        red   = ((ush)r << 8);
+                        green = ((ush)g << 8);
+                        blue  = ((ush)b << 8);
+                    }
+                    pixel = ((red   >> RShift) & RMask) |
+                            ((green >> GShift) & GMask) |
+                            ((blue  >> BShift) & BMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            }
+            /* display after every 16 lines */
+            if (((row+1) & 0xf) == 0) {
+                XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,
+                  (int)lastrow, image_width, 16);
+                XFlush(display);
+                lastrow = row + 1;
+            }
+        }
+
+    } else /* depth == 8 */ {
+
+        /* GRR:  add 8-bit support */
+
+    }
+
+    Trace((stderr, "calling final XPutImage()\n"))
+    if (lastrow < image_height) {
+        XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,
+          (int)lastrow, image_width, image_height-lastrow);
+        XFlush(display);
+    }
+
+    return 0;
+}
+
+
+
+
+static void rpng_x_cleanup(void)
+{
+    if (image_data) {
+        free(image_data);
+        image_data = NULL;
+    }
+
+    if (ximage) {
+        if (ximage->data) {
+            free(ximage->data);           /* we allocated it, so we free it */
+            ximage->data = (char *)NULL;  /*  instead of XDestroyImage() */
+        }
+        XDestroyImage(ximage);
+        ximage = NULL;
+    }
+
+    if (have_gc)
+        XFreeGC(display, gc);
+
+    if (have_window)
+        XDestroyWindow(display, window);
+
+    if (have_colormap)
+        XFreeColormap(display, colormap);
+
+    if (have_nondefault_visual)
+        XFree(visual_list);
+}
+
+
+
+
+
+static int rpng_x_msb(ulg u32val)
+{
+    int i;
+
+    for (i = 31;  i >= 0;  --i) {
+        if (u32val & 0x80000000L)
+            break;
+        u32val <<= 1;
+    }
+    return i;
+}
diff --git a/gs/libpng/contrib/gregbook/rpng2-win.c b/gs/libpng/contrib/gregbook/rpng2-win.c
new file mode 100644
index 000000000..0c1a9d16e
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/rpng2-win.c
@@ -0,0 +1,1166 @@
+/*---------------------------------------------------------------------------
+
+   rpng2 - progressive-model PNG display program                rpng2-win.c
+
+   This program decodes and displays PNG files progressively, as if it were
+   a web browser (though the front end is only set up to read from files).
+   It supports gamma correction, user-specified background colors, and user-
+   specified background patterns (for transparent images).  This version is
+   for 32-bit Windows; it may compile under 16-bit Windows with a little
+   tweaking (or maybe not).  Thanks to Adam Costello and Pieter S. van der
+   Meulen for the "diamond" and "radial waves" patterns, respectively.
+
+   to do:
+    - handle quoted command-line args (especially filenames with spaces)
+    - finish resizable checkerboard-gradient (sizes 4-128?)
+    - use %.1023s to simplify truncation of title-bar string?
+    - have minimum window width:  oh well
+
+  ---------------------------------------------------------------------------
+
+   Changelog:
+    - 1.01:  initial public release
+    - 1.02:  fixed cut-and-paste error in usage screen (oops...)
+    - 1.03:  modified to allow abbreviated options
+    - 1.04:  removed bogus extra argument from usage fprintf() [Glenn R-P?];
+              fixed command-line parsing bug
+    - 1.10:  enabled "message window"/console (thanks to David Geldreich)
+    - 1.20:  added runtime MMX-enabling/disabling and new -mmx* options
+    - 1.21:  made minor tweak to usage screen to fit within 25-line console
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2001 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "rpng2-win"
+#define LONGNAME  "Progressive PNG Viewer for Windows"
+#define VERSION   "1.21 of 29 June 2001"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <setjmp.h>    /* for jmpbuf declaration in readpng2.h */
+#include <time.h>
+#include <math.h>      /* only for PvdM background code */
+#include <windows.h>
+#include <conio.h>     /* only for _getch() */
+
+/* all for PvdM background code: */
+#ifndef PI
+#  define PI             3.141592653589793238
+#endif
+#define PI_2             (PI*0.5)
+#define INV_PI_360       (360.0 / PI)
+#define MAX(a,b)         (a>b?a:b)
+#define MIN(a,b)         (a<b?a:b)
+#define CLIP(a,min,max)  MAX(min,MIN((a),max))
+#define ABS(a)           ((a)<0?-(a):(a))
+#define CLIP8P(c)        MAX(0,(MIN((c),255)))   /* 8-bit pos. integer (uch) */
+#define ROUNDF(f)        ((int)(f + 0.5))
+
+#define rgb1_max   bg_freq
+#define rgb1_min   bg_gray
+#define rgb2_max   bg_bsat
+#define rgb2_min   bg_brot
+
+/* #define DEBUG */     /* this enables the Trace() macros */
+
+#include "readpng2.h"   /* typedefs, common macros, readpng2 prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects
+ * only happen with alpha (which could easily be avoided with
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) {               \
+    ush temp = ((ush)(fg)*(ush)(alpha) +                          \
+                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \
+    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \
+}
+
+
+#define INBUFSIZE 4096   /* with pseudo-timing on (1 sec delay/block), this
+                          *  block size corresponds roughly to a download
+                          *  speed 10% faster than theoretical 33.6K maximum
+                          *  (assuming 8 data bits, 1 stop bit and no other
+                          *  overhead) */
+
+/* local prototypes */
+static void       rpng2_win_init(void);
+static int        rpng2_win_create_window(void);
+static int        rpng2_win_load_bg_image(void);
+static void       rpng2_win_display_row(ulg row);
+static void       rpng2_win_finish_display(void);
+static void       rpng2_win_cleanup(void);
+LRESULT CALLBACK  rpng2_win_wndproc(HWND, UINT, WPARAM, LPARAM);
+
+
+static char titlebar[1024], *window_name = titlebar;
+static char *progname = PROGNAME;
+static char *appname = LONGNAME;
+static char *icon_name = PROGNAME;    /* GRR:  not (yet) used */
+static char *filename;
+static FILE *infile;
+
+static mainprog_info rpng2_info;
+
+static uch inbuf[INBUFSIZE];
+static int incount;
+
+static int pat = 6;         /* must be less than num_bgpat */
+static int bg_image = 0;
+static int bgscale = 16;
+static ulg bg_rowbytes;
+static uch *bg_data;
+
+static struct rgb_color {
+    uch r, g, b;
+} rgb[] = {
+    {  0,   0,   0},    /*  0:  black */
+    {255, 255, 255},    /*  1:  white */
+    {173, 132,  57},    /*  2:  tan */
+    { 64, 132,   0},    /*  3:  medium green */
+    {189, 117,   1},    /*  4:  gold */
+    {253, 249,   1},    /*  5:  yellow */
+    {  0,   0, 255},    /*  6:  blue */
+    {  0,   0, 120},    /*  7:  medium blue */
+    {255,   0, 255},    /*  8:  magenta */
+    { 64,   0,  64},    /*  9:  dark magenta */
+    {255,   0,   0},    /* 10:  red */
+    { 64,   0,   0},    /* 11:  dark red */
+    {255, 127,   0},    /* 12:  orange */
+    {192,  96,   0},    /* 13:  darker orange */
+    { 24,  60,   0},    /* 14:  dark green-yellow */
+    { 85, 125, 200}     /* 15:  ice blue */
+};
+/* not used for now, but should be for error-checking:
+static int num_rgb = sizeof(rgb) / sizeof(struct rgb_color);
+ */
+
+/*
+    This whole struct is a fairly cheesy way to keep the number of
+    command-line options to a minimum.  The radial-waves background
+    type is a particularly poor fit to the integer elements of the
+    struct...but a few macros and a little fixed-point math will do
+    wonders for ya.
+
+    type bits:
+       F E D C B A 9 8 7 6 5 4 3 2 1 0
+                             | | | | |
+                             | | +-+-+-- 0 = sharp-edged checkerboard
+                             | |         1 = soft diamonds
+                             | |         2 = radial waves
+                             | |       3-7 = undefined
+                             | +-- gradient #2 inverted?
+                             +-- alternating columns inverted?
+ */
+static struct background_pattern {
+    ush type;
+    int rgb1_max, rgb1_min;     /* or bg_freq, bg_gray */
+    int rgb2_max, rgb2_min;     /* or bg_bsat, bg_brot (both scaled by 10)*/
+} bg[] = {
+    {0+8,   2,0,  1,15},        /* checkered:  tan/black vs. white/ice blue */
+    {0+24,  2,0,  1,0},         /* checkered:  tan/black vs. white/black */
+    {0+8,   4,5,  0,2},         /* checkered:  gold/yellow vs. black/tan */
+    {0+8,   4,5,  0,6},         /* checkered:  gold/yellow vs. black/blue */
+    {0,     7,0,  8,9},         /* checkered:  deep blue/black vs. magenta */
+    {0+8,  13,0,  5,14},        /* checkered:  orange/black vs. yellow */
+    {0+8,  12,0, 10,11},        /* checkered:  orange/black vs. red */
+    {1,     7,0,  8,0},         /* diamonds:  deep blue/black vs. magenta */
+    {1,    12,0, 11,0},         /* diamonds:  orange vs. dark red */
+    {1,    10,0,  7,0},         /* diamonds:  red vs. medium blue */
+    {1,     4,0,  5,0},         /* diamonds:  gold vs. yellow */
+    {1,     3,0,  0,0},         /* diamonds:  medium green vs. black */
+    {2,    16, 100,  20,   0},  /* radial:  ~hard radial color-beams */
+    {2,    18, 100,  10,   2},  /* radial:  soft, curved radial color-beams */
+    {2,    16, 256, 100, 250},  /* radial:  very tight spiral */
+    {2, 10000, 256,  11,   0}   /* radial:  dipole-moire' (almost fractal) */
+};
+static int num_bgpat = sizeof(bg) / sizeof(struct background_pattern);
+
+
+/* Windows-specific global variables (could go in struct, but messy...) */
+static ulg wimage_rowbytes;
+static uch *dib;
+static uch *wimage_data;
+static BITMAPINFOHEADER *bmih;
+
+static HWND global_hwnd;
+static HINSTANCE global_hInst;
+static int global_showmode;
+
+
+
+
+int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
+{
+    char *args[1024];                 /* arbitrary limit, but should suffice */
+    char **argv = args;
+    char *p, *q, *bgstr = NULL;
+    int argc = 0;
+    int rc, alen, flen;
+    int error = 0;
+    int timing = FALSE;
+    int have_bg = FALSE;
+    double LUT_exponent;              /* just the lookup table */
+    double CRT_exponent = 2.2;        /* just the monitor */
+    double default_display_exponent;  /* whole display system */
+    MSG msg;
+
+
+    /* First initialize a few things, just to be sure--memset takes care of
+     * default background color (black), booleans (FALSE), pointers (NULL),
+     * etc. */
+
+    global_hInst = hInst;
+    global_showmode = showmode;
+    filename = (char *)NULL;
+    memset(&rpng2_info, 0, sizeof(mainprog_info));
+
+
+    /* Next reenable console output, which normally goes to the bit bucket
+     * for windowed apps.  Closing the console window will terminate the
+     * app.  Thanks to David.Geldreich@realviz.com for supplying the magical
+     * incantation. */
+
+    AllocConsole();
+    freopen("CONOUT$", "a", stderr);
+    freopen("CONOUT$", "a", stdout);
+
+
+    /* Set the default value for our display-system exponent, i.e., the
+     * product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  This is not an
+     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+     * ones), but it should cover 99% of the current possibilities.  And
+     * yes, these ifdefs are completely wasted in a Windows program... */
+
+#if defined(NeXT)
+    /* third-party utilities can modify the default LUT exponent */
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to
+     * get the "gamma" value, so we do it the hard way */
+    infile = fopen("/etc/config/system.glGammaVal", "r");
+    if (infile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, infile);
+        fclose(infile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL)
+        rpng2_info.display_exponent = atof(p);
+    else
+        rpng2_info.display_exponent = default_display_exponent;
+
+
+    /* Windows really hates command lines, so we have to set up our own argv.
+     * Note that we do NOT bother with quoted arguments here, so don't use
+     * filenames with spaces in 'em! */
+
+    argv[argc++] = PROGNAME;
+    p = cmd;
+    for (;;) {
+        if (*p == ' ')
+            while (*++p == ' ')
+                ;
+        /* now p points at the first non-space after some spaces */
+        if (*p == '\0')
+            break;    /* nothing after the spaces:  done */
+        argv[argc++] = q = p;
+        while (*q && *q != ' ')
+            ++q;
+        /* now q points at a space or the end of the string */
+        if (*q == '\0')
+            break;    /* last argv already terminated; quit */
+        *q = '\0';    /* change space to terminator */
+        p = q + 1;
+    }
+    argv[argc] = NULL;   /* terminate the argv array itself */
+
+
+    /* Now parse the command line for options and the PNG filename. */
+
+    while (*++argv && !error) {
+        if (!strncmp(*argv, "-gamma", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                rpng2_info.display_exponent = atof(*argv);
+                if (rpng2_info.display_exponent <= 0.0)
+                    ++error;
+            }
+        } else if (!strncmp(*argv, "-bgcolor", 4)) {
+            if (!*++argv)
+                ++error;
+            else {
+                bgstr = *argv;
+                if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                    ++error;
+                else {
+                    have_bg = TRUE;
+                    bg_image = FALSE;
+                }
+            }
+        } else if (!strncmp(*argv, "-bgpat", 4)) {
+            if (!*++argv)
+                ++error;
+            else {
+                pat = atoi(*argv) - 1;
+                if (pat < 0 || pat >= num_bgpat)
+                    ++error;
+                else {
+                    bg_image = TRUE;
+                    have_bg = FALSE;
+                }
+            }
+        } else if (!strncmp(*argv, "-timing", 2)) {
+            timing = TRUE;
+#if (defined(__i386__) || defined(_M_IX86))
+        } else if (!strncmp(*argv, "-nommxfilters", 7)) {
+            rpng2_info.nommxfilters = TRUE;
+        } else if (!strncmp(*argv, "-nommxcombine", 7)) {
+            rpng2_info.nommxcombine = TRUE;
+        } else if (!strncmp(*argv, "-nommxinterlace", 7)) {
+            rpng2_info.nommxinterlace = TRUE;
+        } else if (!strcmp(*argv, "-nommx")) {
+            rpng2_info.nommxfilters = TRUE;
+            rpng2_info.nommxcombine = TRUE;
+            rpng2_info.nommxinterlace = TRUE;
+#endif
+        } else {
+            if (**argv != '-') {
+                filename = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+    if (!filename) {
+        ++error;
+    } else if (!(infile = fopen(filename, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
+        ++error;
+    } else {
+        incount = fread(inbuf, 1, INBUFSIZE, infile);
+        if (incount < 8 || !readpng2_check_sig(inbuf, 8)) {
+            fprintf(stderr, PROGNAME
+              ":  [%s] is not a PNG file: incorrect signature\n",
+              filename);
+            ++error;
+        } else if ((rc = readpng2_init(&rpng2_info)) != 0) {
+            switch (rc) {
+                case 2:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] has bad IHDR (libpng longjmp)\n",
+                      filename);
+                    break;
+                case 4:
+                    fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                    break;
+                default:
+                    fprintf(stderr, PROGNAME
+                      ":  unknown readpng2_init() error\n");
+                    break;
+            }
+            ++error;
+        }
+        if (error)
+            fclose(infile);
+    }
+
+
+    /* usage screen */
+
+    if (error) {
+        int ch;
+
+        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);
+        readpng2_version_info();
+        fprintf(stderr, "\n"
+          "Usage:  %s [-gamma exp] [-bgcolor bg | -bgpat pat] [-timing]\n"
+#if (defined(__i386__) || defined(_M_IX86))
+          "        %*s [[-nommxfilters] [-nommxcombine] [-nommxinterlace] | -nommx]\n"
+#endif
+          "        %*s file.png\n\n"
+          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+          "\t\t  to the product of the lookup-table exponent (varies)\n"
+          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+          "    bg  \tdesired background color in 7-character hex RGB format\n"
+          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
+          "\t\t  used with transparent images; overrides -bgpat option\n"
+          "    pat \tdesired background pattern number (1-%d); used with\n"
+          "\t\t  transparent images; overrides -bgcolor option\n"
+          "    -timing\tenables delay for every block read, to simulate modem\n"
+          "\t\t  download of image (~36 Kbps)\n"
+#if (defined(__i386__) || defined(_M_IX86))
+          "    -nommx*\tdisable optimized MMX routines for decoding row filters,\n"
+          "\t\t  combining rows, and expanding interlacing, respectively\n"
+#endif
+          "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
+          "Press Q or Esc to quit this usage screen. ",
+          PROGNAME,
+#if (defined(__i386__) || defined(_M_IX86))
+          strlen(PROGNAME), " ",
+#endif
+          strlen(PROGNAME), " ", default_display_exponent, num_bgpat);
+        fflush(stderr);
+        do
+            ch = _getch();
+        while (ch != 'q' && ch != 'Q' && ch != 0x1B);
+        exit(1);
+    } else {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
+        fprintf(stderr,
+          "\n   [console window:  closing this window will terminate %s]\n\n",
+          PROGNAME);
+        fflush(stderr);
+    }
+
+
+    /* set the title-bar string, but make sure buffer doesn't overflow */
+
+    alen = strlen(appname);
+    flen = strlen(filename);
+    if (alen + flen + 3 > 1023)
+        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));
+    else
+        sprintf(titlebar, "%s:  %s", appname, filename);
+
+
+    /* set some final rpng2_info variables before entering main data loop */
+
+    if (have_bg) {
+        unsigned r, g, b;   /* this approach quiets compiler warnings */
+
+        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+        rpng2_info.bg_red   = (uch)r;
+        rpng2_info.bg_green = (uch)g;
+        rpng2_info.bg_blue  = (uch)b;
+    } else
+        rpng2_info.need_bgcolor = TRUE;
+
+    rpng2_info.done = FALSE;
+    rpng2_info.mainprog_init = rpng2_win_init;
+    rpng2_info.mainprog_display_row = rpng2_win_display_row;
+    rpng2_info.mainprog_finish_display = rpng2_win_finish_display;
+
+
+    /* OK, this is the fun part:  call readpng2_decode_data() at the start of
+     * the loop to deal with our first buffer of data (read in above to verify
+     * that the file is a PNG image), then loop through the file and continue
+     * calling the same routine to handle each chunk of data.  It in turn
+     * passes the data to libpng, which will invoke one or more of our call-
+     * backs as decoded data become available.  We optionally call Sleep() for
+     * one second per iteration to simulate downloading the image via an analog
+     * modem. */
+
+    for (;;) {
+        Trace((stderr, "about to call readpng2_decode_data()\n"))
+        if (readpng2_decode_data(&rpng2_info, inbuf, incount))
+            ++error;
+        Trace((stderr, "done with readpng2_decode_data()\n"))
+        if (error || feof(infile) || rpng2_info.done)
+            break;
+        if (timing)
+            Sleep(1000L);
+        incount = fread(inbuf, 1, INBUFSIZE, infile);
+    }
+
+
+    /* clean up PNG stuff and report any decoding errors */
+
+    fclose(infile);
+    Trace((stderr, "about to call readpng2_cleanup()\n"))
+    readpng2_cleanup(&rpng2_info);
+
+    if (error) {
+        fprintf(stderr, PROGNAME ":  libpng error while decoding PNG image\n");
+        exit(3);
+    }
+
+
+    /* wait for the user to tell us when to quit */
+
+    while (GetMessage(&msg, NULL, 0, 0)) {
+        TranslateMessage(&msg);
+        DispatchMessage(&msg);
+    }
+
+
+    /* we're done:  clean up all image and Windows resources and go away */
+
+    Trace((stderr, "about to call rpng2_win_cleanup()\n"))
+    rpng2_win_cleanup();
+
+    return msg.wParam;
+}
+
+
+
+
+
+/* this function is called by readpng2_info_callback() in readpng2.c, which
+ * in turn is called by libpng after all of the pre-IDAT chunks have been
+ * read and processed--i.e., we now have enough info to finish initializing */
+
+static void rpng2_win_init()
+{
+    ulg i;
+    ulg rowbytes = rpng2_info.rowbytes;
+
+    Trace((stderr, "beginning rpng2_win_init()\n"))
+    Trace((stderr, "  rowbytes = %ld\n", rpng2_info.rowbytes))
+    Trace((stderr, "  width  = %ld\n", rpng2_info.width))
+    Trace((stderr, "  height = %ld\n", rpng2_info.height))
+
+    rpng2_info.image_data = (uch *)malloc(rowbytes * rpng2_info.height);
+    if (!rpng2_info.image_data) {
+        readpng2_cleanup(&rpng2_info);
+        return;
+    }
+
+    rpng2_info.row_pointers = (uch **)malloc(rpng2_info.height * sizeof(uch *));
+    if (!rpng2_info.row_pointers) {
+        free(rpng2_info.image_data);
+        rpng2_info.image_data = NULL;
+        readpng2_cleanup(&rpng2_info);
+        return;
+    }
+
+    for (i = 0;  i < rpng2_info.height;  ++i)
+        rpng2_info.row_pointers[i] = rpng2_info.image_data + i*rowbytes;
+
+/*---------------------------------------------------------------------------
+    Do the basic Windows initialization stuff, make the window, and fill it
+    with the user-specified, file-specified or default background color.
+  ---------------------------------------------------------------------------*/
+
+    if (rpng2_win_create_window()) {
+        readpng2_cleanup(&rpng2_info);
+        return;
+    }
+}
+
+
+
+
+
+static int rpng2_win_create_window()
+{
+    uch bg_red   = rpng2_info.bg_red;
+    uch bg_green = rpng2_info.bg_green;
+    uch bg_blue  = rpng2_info.bg_blue;
+    uch *dest;
+    int extra_width, extra_height;
+    ulg i, j;
+    WNDCLASSEX wndclass;
+    RECT rect;
+
+
+/*---------------------------------------------------------------------------
+    Allocate memory for the display-specific version of the image (round up
+    to multiple of 4 for Windows DIB).
+  ---------------------------------------------------------------------------*/
+
+    wimage_rowbytes = ((3*rpng2_info.width + 3L) >> 2) << 2;
+
+    if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) +
+                              wimage_rowbytes*rpng2_info.height)))
+    {
+        return 4;   /* fail */
+    }
+
+/*---------------------------------------------------------------------------
+    Initialize the DIB.  Negative height means to use top-down BMP ordering
+    (must be uncompressed, but that's what we want).  Bit count of 1, 4 or 8
+    implies a colormap of RGBX quads, but 24-bit BMPs just use B,G,R values
+    directly => wimage_data begins immediately after BMP header.
+  ---------------------------------------------------------------------------*/
+
+    memset(dib, 0, sizeof(BITMAPINFOHEADER));
+    bmih = (BITMAPINFOHEADER *)dib;
+    bmih->biSize = sizeof(BITMAPINFOHEADER);
+    bmih->biWidth = rpng2_info.width;
+    bmih->biHeight = -((long)rpng2_info.height);
+    bmih->biPlanes = 1;
+    bmih->biBitCount = 24;
+    bmih->biCompression = 0;
+    wimage_data = dib + sizeof(BITMAPINFOHEADER);
+
+/*---------------------------------------------------------------------------
+    Fill window with the specified background color (default is black), but
+    defer loading faked "background image" until window is displayed (may be
+    slow to compute).  Data are in BGR order.
+  ---------------------------------------------------------------------------*/
+
+    if (bg_image) {   /* just fill with black for now */
+        memset(wimage_data, 0, wimage_rowbytes*rpng2_info.height);
+    } else {
+        for (j = 0;  j < rpng2_info.height;  ++j) {
+            dest = wimage_data + j*wimage_rowbytes;
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                *dest++ = bg_blue;
+                *dest++ = bg_green;
+                *dest++ = bg_red;
+            }
+        }
+    }
+
+/*---------------------------------------------------------------------------
+    Set the window parameters.
+  ---------------------------------------------------------------------------*/
+
+    memset(&wndclass, 0, sizeof(wndclass));
+
+    wndclass.cbSize = sizeof(wndclass);
+    wndclass.style = CS_HREDRAW | CS_VREDRAW;
+    wndclass.lpfnWndProc = rpng2_win_wndproc;
+    wndclass.hInstance = global_hInst;
+    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
+    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
+    wndclass.hbrBackground = (HBRUSH)GetStockObject(DKGRAY_BRUSH);
+    wndclass.lpszMenuName = NULL;
+    wndclass.lpszClassName = progname;
+    wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
+
+    RegisterClassEx(&wndclass);
+
+/*---------------------------------------------------------------------------
+    Finally, create the window.
+  ---------------------------------------------------------------------------*/
+
+    extra_width  = 2*(GetSystemMetrics(SM_CXBORDER) +
+                      GetSystemMetrics(SM_CXDLGFRAME));
+    extra_height = 2*(GetSystemMetrics(SM_CYBORDER) +
+                      GetSystemMetrics(SM_CYDLGFRAME)) +
+                      GetSystemMetrics(SM_CYCAPTION);
+
+    global_hwnd = CreateWindow(progname, titlebar, WS_OVERLAPPEDWINDOW,
+      CW_USEDEFAULT, CW_USEDEFAULT, rpng2_info.width+extra_width,
+      rpng2_info.height+extra_height, NULL, NULL, global_hInst, NULL);
+
+    ShowWindow(global_hwnd, global_showmode);
+    UpdateWindow(global_hwnd);
+
+/*---------------------------------------------------------------------------
+    Now compute the background image and display it.  If it fails (memory
+    allocation), revert to a plain background color.
+  ---------------------------------------------------------------------------*/
+
+    if (bg_image) {
+        static const char *msg = "Computing background image...";
+        int x, y, len = strlen(msg);
+        HDC hdc = GetDC(global_hwnd);
+        TEXTMETRIC tm;
+
+        GetTextMetrics(hdc, &tm);
+        x = (rpng2_info.width - len*tm.tmAveCharWidth)/2;
+        y = (rpng2_info.height - tm.tmHeight)/2;
+        SetBkMode(hdc, TRANSPARENT);
+        SetTextColor(hdc, GetSysColor(COLOR_HIGHLIGHTTEXT));
+        /* this can still begin out of bounds even if x is positive (???): */
+        TextOut(hdc, ((x < 0)? 0 : x), ((y < 0)? 0 : y), msg, len);
+        ReleaseDC(global_hwnd, hdc);
+
+        rpng2_win_load_bg_image();   /* resets bg_image if fails */
+    }
+
+    if (!bg_image) {
+        for (j = 0;  j < rpng2_info.height;  ++j) {
+            dest = wimage_data + j*wimage_rowbytes;
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                *dest++ = bg_blue;
+                *dest++ = bg_green;
+                *dest++ = bg_red;
+            }
+        }
+    }
+
+    rect.left = 0L;
+    rect.top = 0L;
+    rect.right = (LONG)rpng2_info.width;       /* possibly off by one? */
+    rect.bottom = (LONG)rpng2_info.height;     /* possibly off by one? */
+    InvalidateRect(global_hwnd, &rect, FALSE);
+    UpdateWindow(global_hwnd);                 /* similar to XFlush() */
+
+    return 0;
+
+} /* end function rpng2_win_create_window() */
+
+
+
+
+
+static int rpng2_win_load_bg_image()
+{
+    uch *src, *dest;
+    uch r1, r2, g1, g2, b1, b2;
+    uch r1_inv, r2_inv, g1_inv, g2_inv, b1_inv, b2_inv;
+    int k, hmax, max;
+    int xidx, yidx, yidx_max = (bgscale-1);
+    int even_odd_vert, even_odd_horiz, even_odd;
+    int invert_gradient2 = (bg[pat].type & 0x08);
+    int invert_column;
+    ulg i, row;
+
+/*---------------------------------------------------------------------------
+    Allocate buffer for fake background image to be used with transparent
+    images; if this fails, revert to plain background color.
+  ---------------------------------------------------------------------------*/
+
+    bg_rowbytes = 3 * rpng2_info.width;
+    bg_data = (uch *)malloc(bg_rowbytes * rpng2_info.height);
+    if (!bg_data) {
+        fprintf(stderr, PROGNAME
+          ":  unable to allocate memory for background image\n");
+        bg_image = 0;
+        return 1;
+    }
+
+/*---------------------------------------------------------------------------
+    Vertical gradients (ramps) in NxN squares, alternating direction and
+    colors (N == bgscale).
+  ---------------------------------------------------------------------------*/
+
+    if ((bg[pat].type & 0x07) == 0) {
+        uch r1_min  = rgb[bg[pat].rgb1_min].r;
+        uch g1_min  = rgb[bg[pat].rgb1_min].g;
+        uch b1_min  = rgb[bg[pat].rgb1_min].b;
+        uch r2_min  = rgb[bg[pat].rgb2_min].r;
+        uch g2_min  = rgb[bg[pat].rgb2_min].g;
+        uch b2_min  = rgb[bg[pat].rgb2_min].b;
+        int r1_diff = rgb[bg[pat].rgb1_max].r - r1_min;
+        int g1_diff = rgb[bg[pat].rgb1_max].g - g1_min;
+        int b1_diff = rgb[bg[pat].rgb1_max].b - b1_min;
+        int r2_diff = rgb[bg[pat].rgb2_max].r - r2_min;
+        int g2_diff = rgb[bg[pat].rgb2_max].g - g2_min;
+        int b2_diff = rgb[bg[pat].rgb2_max].b - b2_min;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            yidx = row % bgscale;
+            even_odd_vert = (row / bgscale) & 1;
+
+            r1 = r1_min + (r1_diff * yidx) / yidx_max;
+            g1 = g1_min + (g1_diff * yidx) / yidx_max;
+            b1 = b1_min + (b1_diff * yidx) / yidx_max;
+            r1_inv = r1_min + (r1_diff * (yidx_max-yidx)) / yidx_max;
+            g1_inv = g1_min + (g1_diff * (yidx_max-yidx)) / yidx_max;
+            b1_inv = b1_min + (b1_diff * (yidx_max-yidx)) / yidx_max;
+
+            r2 = r2_min + (r2_diff * yidx) / yidx_max;
+            g2 = g2_min + (g2_diff * yidx) / yidx_max;
+            b2 = b2_min + (b2_diff * yidx) / yidx_max;
+            r2_inv = r2_min + (r2_diff * (yidx_max-yidx)) / yidx_max;
+            g2_inv = g2_min + (g2_diff * (yidx_max-yidx)) / yidx_max;
+            b2_inv = b2_min + (b2_diff * (yidx_max-yidx)) / yidx_max;
+
+            dest = bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                even_odd_horiz = (i / bgscale) & 1;
+                even_odd = even_odd_vert ^ even_odd_horiz;
+                invert_column =
+                  (even_odd_horiz && (bg[pat].type & 0x10));
+                if (even_odd == 0) {         /* gradient #1 */
+                    if (invert_column) {
+                        *dest++ = r1_inv;
+                        *dest++ = g1_inv;
+                        *dest++ = b1_inv;
+                    } else {
+                        *dest++ = r1;
+                        *dest++ = g1;
+                        *dest++ = b1;
+                    }
+                } else {                     /* gradient #2 */
+                    if ((invert_column && invert_gradient2) ||
+                        (!invert_column && !invert_gradient2))
+                    {
+                        *dest++ = r2;        /* not inverted or */
+                        *dest++ = g2;        /*  doubly inverted */
+                        *dest++ = b2;
+                    } else {
+                        *dest++ = r2_inv;
+                        *dest++ = g2_inv;    /* singly inverted */
+                        *dest++ = b2_inv;
+                    }
+                }
+            }
+        }
+
+/*---------------------------------------------------------------------------
+    Soft gradient-diamonds with scale = bgscale.  Code contributed by Adam
+    M. Costello.
+  ---------------------------------------------------------------------------*/
+
+    } else if ((bg[pat].type & 0x07) == 1) {
+
+        hmax = (bgscale-1)/2;   /* half the max weight of a color */
+        max = 2*hmax;           /* the max weight of a color */
+
+        r1 = rgb[bg[pat].rgb1_max].r;
+        g1 = rgb[bg[pat].rgb1_max].g;
+        b1 = rgb[bg[pat].rgb1_max].b;
+        r2 = rgb[bg[pat].rgb2_max].r;
+        g2 = rgb[bg[pat].rgb2_max].g;
+        b2 = rgb[bg[pat].rgb2_max].b;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            yidx = row % bgscale;
+            if (yidx > hmax)
+                yidx = bgscale-1 - yidx;
+            dest = bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                xidx = i % bgscale;
+                if (xidx > hmax)
+                    xidx = bgscale-1 - xidx;
+                k = xidx + yidx;
+                *dest++ = (k*r1 + (max-k)*r2) / max;
+                *dest++ = (k*g1 + (max-k)*g2) / max;
+                *dest++ = (k*b1 + (max-k)*b2) / max;
+            }
+        }
+
+/*---------------------------------------------------------------------------
+    Radial "starburst" with azimuthal sinusoids; [eventually number of sinu-
+    soids will equal bgscale?].  This one is slow but very cool.  Code con-
+    tributed by Pieter S. van der Meulen (originally in Smalltalk).
+  ---------------------------------------------------------------------------*/
+
+    } else if ((bg[pat].type & 0x07) == 2) {
+        uch ch;
+        int ii, x, y, hw, hh, grayspot;
+        double freq, rotate, saturate, gray, intensity;
+        double angle=0.0, aoffset=0.0, maxDist, dist;
+        double red=0.0, green=0.0, blue=0.0, hue, s, v, f, p, q, t;
+
+        fprintf(stderr, "%s:  computing radial background...",
+          PROGNAME);
+        fflush(stderr);
+
+        hh = rpng2_info.height / 2;
+        hw = rpng2_info.width / 2;
+
+        /* variables for radial waves:
+         *   aoffset:  number of degrees to rotate hue [CURRENTLY NOT USED]
+         *   freq:  number of color beams originating from the center
+         *   grayspot:  size of the graying center area (anti-alias)
+         *   rotate:  rotation of the beams as a function of radius
+         *   saturate:  saturation of beams' shape azimuthally
+         */
+        angle = CLIP(angle, 0.0, 360.0);
+        grayspot = CLIP(bg[pat].bg_gray, 1, (hh + hw));
+        freq = MAX((double)bg[pat].bg_freq, 0.0);
+        saturate = (double)bg[pat].bg_bsat * 0.1;
+        rotate = (double)bg[pat].bg_brot * 0.1;
+        gray = 0.0;
+        intensity = 0.0;
+        maxDist = (double)((hw*hw) + (hh*hh));
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            y = row - hh;
+            dest = bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                x = i - hw;
+                angle = (x == 0)? PI_2 : atan((double)y / (double)x);
+                gray = (double)MAX(ABS(y), ABS(x)) / grayspot;
+                gray = MIN(1.0, gray);
+                dist = (double)((x*x) + (y*y)) / maxDist;
+                intensity = cos((angle+(rotate*dist*PI)) * freq) *
+                  gray * saturate;
+                intensity = (MAX(MIN(intensity,1.0),-1.0) + 1.0) * 0.5;
+                hue = (angle + PI) * INV_PI_360 + aoffset;
+                s = gray * ((double)(ABS(x)+ABS(y)) / (double)(hw + hh));
+                s = MIN(MAX(s,0.0), 1.0);
+                v = MIN(MAX(intensity,0.0), 1.0);
+
+                if (s == 0.0) {
+                    ch = (uch)(v * 255.0);
+                    *dest++ = ch;
+                    *dest++ = ch;
+                    *dest++ = ch;
+                } else {
+                    if ((hue < 0.0) || (hue >= 360.0))
+                        hue -= (((int)(hue / 360.0)) * 360.0);
+                    hue /= 60.0;
+                    ii = (int)hue;
+                    f = hue - (double)ii;
+                    p = (1.0 - s) * v;
+                    q = (1.0 - (s * f)) * v;
+                    t = (1.0 - (s * (1.0 - f))) * v;
+                    if      (ii == 0) { red = v; green = t; blue = p; }
+                    else if (ii == 1) { red = q; green = v; blue = p; }
+                    else if (ii == 2) { red = p; green = v; blue = t; }
+                    else if (ii == 3) { red = p; green = q; blue = v; }
+                    else if (ii == 4) { red = t; green = p; blue = v; }
+                    else if (ii == 5) { red = v; green = p; blue = q; }
+                    *dest++ = (uch)(red * 255.0);
+                    *dest++ = (uch)(green * 255.0);
+                    *dest++ = (uch)(blue * 255.0);
+                }
+            }
+        }
+        fprintf(stderr, "done.\n");
+        fflush(stderr);
+    }
+
+/*---------------------------------------------------------------------------
+    Blast background image to display buffer before beginning PNG decode;
+    calling function will handle invalidation and UpdateWindow() call.
+  ---------------------------------------------------------------------------*/
+
+    for (row = 0;  row < rpng2_info.height;  ++row) {
+        src = bg_data + row*bg_rowbytes;
+        dest = wimage_data + row*wimage_rowbytes;
+        for (i = rpng2_info.width;  i > 0;  --i) {
+            r1 = *src++;
+            g1 = *src++;
+            b1 = *src++;
+            *dest++ = b1;
+            *dest++ = g1;   /* note reverse order */
+            *dest++ = r1;
+        }
+    }
+
+    return 0;
+
+} /* end function rpng2_win_load_bg_image() */
+
+
+
+
+
+static void rpng2_win_display_row(ulg row)
+{
+    uch bg_red   = rpng2_info.bg_red;
+    uch bg_green = rpng2_info.bg_green;
+    uch bg_blue  = rpng2_info.bg_blue;
+    uch *src, *src2=NULL, *dest;
+    uch r, g, b, a;
+    ulg i;
+    static int rows=0;
+    static ulg firstrow;
+
+/*---------------------------------------------------------------------------
+    rows and firstrow simply track how many rows (and which ones) have not
+    yet been displayed; alternatively, we could call InvalidateRect() for
+    every row and not bother with the records-keeping.
+  ---------------------------------------------------------------------------*/
+
+    Trace((stderr, "beginning rpng2_win_display_row()\n"))
+
+    if (rows == 0)
+        firstrow = row;   /* first row not yet displayed */
+
+    ++rows;   /* count of rows received but not yet displayed */
+
+/*---------------------------------------------------------------------------
+    Aside from the use of the rpng2_info struct and the lack of an outer
+    loop (over rows), this routine is identical to rpng_win_display_image()
+    in the non-progressive version of the program.
+  ---------------------------------------------------------------------------*/
+
+    src = rpng2_info.image_data + row*rpng2_info.rowbytes;
+    if (bg_image)
+        src2 = bg_data + row*bg_rowbytes;
+    dest = wimage_data + row*wimage_rowbytes;
+
+    if (rpng2_info.channels == 3) {
+        for (i = rpng2_info.width;  i > 0;  --i) {
+            r = *src++;
+            g = *src++;
+            b = *src++;
+            *dest++ = b;
+            *dest++ = g;   /* note reverse order */
+            *dest++ = r;
+        }
+    } else /* if (rpng2_info.channels == 4) */ {
+        for (i = rpng2_info.width;  i > 0;  --i) {
+            r = *src++;
+            g = *src++;
+            b = *src++;
+            a = *src++;
+            if (bg_image) {
+                bg_red   = *src2++;
+                bg_green = *src2++;
+                bg_blue  = *src2++;
+            }
+            if (a == 255) {
+                *dest++ = b;
+                *dest++ = g;
+                *dest++ = r;
+            } else if (a == 0) {
+                *dest++ = bg_blue;
+                *dest++ = bg_green;
+                *dest++ = bg_red;
+            } else {
+                /* this macro (copied from png.h) composites the
+                 * foreground and background values and puts the
+                 * result into the first argument; there are no
+                 * side effects with the first argument */
+                alpha_composite(*dest++, b, a, bg_blue);
+                alpha_composite(*dest++, g, a, bg_green);
+                alpha_composite(*dest++, r, a, bg_red);
+            }
+        }
+    }
+
+/*---------------------------------------------------------------------------
+    Display after every 16 rows or when on last row.  (Region may include
+    previously displayed lines due to interlacing--i.e., not contiguous.)
+  ---------------------------------------------------------------------------*/
+
+    if ((rows & 0xf) == 0 || row == rpng2_info.height-1) {
+        RECT rect;
+
+        rect.left = 0L;
+        rect.top = (LONG)firstrow;
+        rect.right = (LONG)rpng2_info.width;       /* possibly off by one? */
+        rect.bottom = (LONG)row + 1L;              /* possibly off by one? */
+        InvalidateRect(global_hwnd, &rect, FALSE);
+        UpdateWindow(global_hwnd);                 /* similar to XFlush() */
+        rows = 0;
+    }
+
+} /* end function rpng2_win_display_row() */
+
+
+
+
+
+static void rpng2_win_finish_display()
+{
+    Trace((stderr, "beginning rpng2_win_finish_display()\n"))
+
+    /* last row has already been displayed by rpng2_win_display_row(), so
+     * we have nothing to do here except set a flag and let the user know
+     * that the image is done */
+
+    rpng2_info.done = TRUE;
+    printf(
+      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n");
+    fflush(stdout);
+}
+
+
+
+
+
+static void rpng2_win_cleanup()
+{
+    if (bg_image && bg_data) {
+        free(bg_data);
+        bg_data = NULL;
+    }
+
+    if (rpng2_info.image_data) {
+        free(rpng2_info.image_data);
+        rpng2_info.image_data = NULL;
+    }
+
+    if (rpng2_info.row_pointers) {
+        free(rpng2_info.row_pointers);
+        rpng2_info.row_pointers = NULL;
+    }
+
+    if (dib) {
+        free(dib);
+        dib = NULL;
+    }
+}
+
+
+
+
+
+LRESULT CALLBACK rpng2_win_wndproc(HWND hwnd, UINT iMsg, WPARAM wP, LPARAM lP)
+{
+    HDC         hdc;
+    PAINTSTRUCT ps;
+    int rc;
+
+    switch (iMsg) {
+        case WM_CREATE:
+            /* one-time processing here, if any */
+            return 0;
+
+        case WM_PAINT:
+            hdc = BeginPaint(hwnd, &ps);
+            rc = StretchDIBits(hdc, 0, 0, rpng2_info.width, rpng2_info.height,
+                                    0, 0, rpng2_info.width, rpng2_info.height,
+                                    wimage_data, (BITMAPINFO *)bmih,
+                                    0, SRCCOPY);
+            EndPaint(hwnd, &ps);
+            return 0;
+
+        /* wait for the user to tell us when to quit */
+        case WM_CHAR:
+            switch (wP) {       /* only need one, so ignore repeat count */
+                case 'q':
+                case 'Q':
+                case 0x1B:      /* Esc key */
+                    PostQuitMessage(0);
+            }
+            return 0;
+
+        case WM_LBUTTONDOWN:    /* another way of quitting */
+        case WM_DESTROY:
+            PostQuitMessage(0);
+            return 0;
+    }
+
+    return DefWindowProc(hwnd, iMsg, wP, lP);
+}
diff --git a/gs/libpng/contrib/gregbook/rpng2-x.c b/gs/libpng/contrib/gregbook/rpng2-x.c
new file mode 100644
index 000000000..5fc29ea77
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/rpng2-x.c
@@ -0,0 +1,1408 @@
+/*---------------------------------------------------------------------------
+
+   rpng2 - progressive-model PNG display program                  rpng2-x.c
+
+   This program decodes and displays PNG files progressively, as if it were
+   a web browser (though the front end is only set up to read from files).
+   It supports gamma correction, user-specified background colors, and user-
+   specified background patterns (for transparent images).  This version is
+   for the X Window System (tested by the author under Unix and by Martin
+   Zinser under OpenVMS; may work under OS/2 with a little tweaking).
+
+   Thanks to Adam Costello and Pieter S. van der Meulen for the "diamond"
+   and "radial waves" patterns, respectively.
+
+   to do:
+    - 8-bit support
+    - finish resizable checkerboard-gradient (sizes 4-128?)
+    - use %.1023s to simplify truncation of title-bar string?
+
+  ---------------------------------------------------------------------------
+
+   Changelog:
+    - 1.01:  initial public release
+    - 1.02:  modified to allow abbreviated options; fixed char/uchar mismatch
+    - 1.10:  added support for non-default visuals; fixed X pixel-conversion
+    - 1.11:  added -usleep option for demos; fixed command-line parsing bug
+    - 1.12:  added -pause option for demos and testing
+    - 1.20:  added runtime MMX-enabling/disabling and new -mmx* options
+    - 1.21:  fixed small X memory leak (thanks to Francois Petitjean)
+    - 1.22:  fixed XFreeGC() crash bug
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2001 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "rpng2-x"
+#define LONGNAME  "Progressive PNG Viewer for X"
+#define VERSION   "1.22 of 16 August 2001"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <setjmp.h>       /* for jmpbuf declaration in readpng2.h */
+#include <time.h>
+#include <math.h>         /* only for PvdM background code */
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <X11/Xos.h>
+#include <X11/keysym.h>   /* defines XK_* macros */
+
+#ifdef VMS
+#  include <unistd.h>
+#endif
+
+/* all for PvdM background code: */
+#ifndef PI
+#  define PI             3.141592653589793238
+#endif
+#define PI_2             (PI*0.5)
+#define INV_PI_360       (360.0 / PI)
+#define MAX(a,b)         (a>b?a:b)
+#define MIN(a,b)         (a<b?a:b)
+#define CLIP(a,min,max)  MAX(min,MIN((a),max))
+#define ABS(a)           ((a)<0?-(a):(a))
+#define CLIP8P(c)        MAX(0,(MIN((c),255)))   /* 8-bit pos. integer (uch) */
+#define ROUNDF(f)        ((int)(f + 0.5))
+
+#define rgb1_max   bg_freq
+#define rgb1_min   bg_gray
+#define rgb2_max   bg_bsat
+#define rgb2_min   bg_brot
+
+/* #define DEBUG */     /* this enables the Trace() macros */
+
+#include "readpng2.h"   /* typedefs, common macros, readpng2 prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects
+ * only happen with alpha (which could easily be avoided with
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) {               \
+    ush temp = ((ush)(fg)*(ush)(alpha) +                          \
+                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \
+    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \
+}
+
+
+#define INBUFSIZE 4096   /* with pseudo-timing on (1 sec delay/block), this
+                          *  block size corresponds roughly to a download
+                          *  speed 10% faster than theoretical 33.6K maximum
+                          *  (assuming 8 data bits, 1 stop bit and no other
+                          *  overhead) */
+
+/* local prototypes */
+static void rpng2_x_init(void);
+static int  rpng2_x_create_window(void);
+static int  rpng2_x_load_bg_image(void);
+static void rpng2_x_display_row(ulg row);
+static void rpng2_x_finish_display(void);
+static void rpng2_x_cleanup(void);
+static int  rpng2_x_msb(ulg u32val);
+
+
+static char titlebar[1024], *window_name = titlebar;
+static char *appname = LONGNAME;
+static char *icon_name = PROGNAME;
+static char *filename;
+static FILE *infile;
+
+static mainprog_info rpng2_info;
+
+static uch inbuf[INBUFSIZE];
+static int incount;
+
+static int pat = 6;        /* must be less than num_bgpat */
+static int bg_image = 0;
+static int bgscale = 16;
+static ulg bg_rowbytes;
+static uch *bg_data;
+
+int pause_after_pass = FALSE;
+int demo_timing = FALSE;
+ulg usleep_duration = 0L;
+
+static struct rgb_color {
+    uch r, g, b;
+} rgb[] = {
+    {  0,   0,   0},    /*  0:  black */
+    {255, 255, 255},    /*  1:  white */
+    {173, 132,  57},    /*  2:  tan */
+    { 64, 132,   0},    /*  3:  medium green */
+    {189, 117,   1},    /*  4:  gold */
+    {253, 249,   1},    /*  5:  yellow */
+    {  0,   0, 255},    /*  6:  blue */
+    {  0,   0, 120},    /*  7:  medium blue */
+    {255,   0, 255},    /*  8:  magenta */
+    { 64,   0,  64},    /*  9:  dark magenta */
+    {255,   0,   0},    /* 10:  red */
+    { 64,   0,   0},    /* 11:  dark red */
+    {255, 127,   0},    /* 12:  orange */
+    {192,  96,   0},    /* 13:  darker orange */
+    { 24,  60,   0},    /* 14:  dark green-yellow */
+    { 85, 125, 200}     /* 15:  ice blue */
+};
+/* not used for now, but should be for error-checking:
+static int num_rgb = sizeof(rgb) / sizeof(struct rgb_color);
+ */
+
+/*
+    This whole struct is a fairly cheesy way to keep the number of
+    command-line options to a minimum.  The radial-waves background
+    type is a particularly poor fit to the integer elements of the
+    struct...but a few macros and a little fixed-point math will do
+    wonders for ya.
+
+    type bits:
+       F E D C B A 9 8 7 6 5 4 3 2 1 0
+                             | | | | |
+                             | | +-+-+-- 0 = sharp-edged checkerboard
+                             | |         1 = soft diamonds
+                             | |         2 = radial waves
+                             | |       3-7 = undefined
+                             | +-- gradient #2 inverted?
+                             +-- alternating columns inverted?
+ */
+static struct background_pattern {
+    ush type;
+    int rgb1_max, rgb1_min;     /* or bg_freq, bg_gray */
+    int rgb2_max, rgb2_min;     /* or bg_bsat, bg_brot (both scaled by 10)*/
+} bg[] = {
+    {0+8,   2,0,  1,15},        /* checkered:  tan/black vs. white/ice blue */
+    {0+24,  2,0,  1,0},         /* checkered:  tan/black vs. white/black */
+    {0+8,   4,5,  0,2},         /* checkered:  gold/yellow vs. black/tan */
+    {0+8,   4,5,  0,6},         /* checkered:  gold/yellow vs. black/blue */
+    {0,     7,0,  8,9},         /* checkered:  deep blue/black vs. magenta */
+    {0+8,  13,0,  5,14},        /* checkered:  orange/black vs. yellow */
+    {0+8,  12,0, 10,11},        /* checkered:  orange/black vs. red */
+    {1,     7,0,  8,0},         /* diamonds:  deep blue/black vs. magenta */
+    {1,    12,0, 11,0},         /* diamonds:  orange vs. dark red */
+    {1,    10,0,  7,0},         /* diamonds:  red vs. medium blue */
+    {1,     4,0,  5,0},         /* diamonds:  gold vs. yellow */
+    {1,     3,0,  0,0},         /* diamonds:  medium green vs. black */
+    {2,    16, 100,  20,   0},  /* radial:  ~hard radial color-beams */
+    {2,    18, 100,  10,   2},  /* radial:  soft, curved radial color-beams */
+    {2,    16, 256, 100, 250},  /* radial:  very tight spiral */
+    {2, 10000, 256,  11,   0}   /* radial:  dipole-moire' (almost fractal) */
+};
+static int num_bgpat = sizeof(bg) / sizeof(struct background_pattern);
+
+
+/* X-specific variables */
+static char *displayname;
+static XImage *ximage;
+static Display *display;
+static int depth;
+static Visual *visual;
+static XVisualInfo *visual_list;
+static int RShift, GShift, BShift;
+static ulg RMask, GMask, BMask;
+static Window window;
+static GC gc;
+static Colormap colormap;
+
+static int have_nondefault_visual = FALSE;
+static int have_colormap = FALSE;
+static int have_window = FALSE;
+static int have_gc = FALSE;
+
+
+
+
+int main(int argc, char **argv)
+{
+#ifdef sgi
+    char tmpline[80];
+#endif
+    char *p, *bgstr = NULL;
+    int rc, alen, flen;
+    int error = 0;
+    int timing = FALSE;
+    int have_bg = FALSE;
+    double LUT_exponent;                /* just the lookup table */
+    double CRT_exponent = 2.2;          /* just the monitor */
+    double default_display_exponent;    /* whole display system */
+    XEvent e;
+    KeySym k;
+
+
+    /* First initialize a few things, just to be sure--memset takes care of
+     * default background color (black), booleans (FALSE), pointers (NULL),
+     * etc. */
+
+    displayname = (char *)NULL;
+    filename = (char *)NULL;
+    memset(&rpng2_info, 0, sizeof(mainprog_info));
+
+
+    /* Set the default value for our display-system exponent, i.e., the
+     * product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  This is not an
+     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+     * ones), but it should cover 99% of the current possibilities. */
+
+#if defined(NeXT)
+    /* third-party utilities can modify the default LUT exponent */
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to
+     * get the "gamma" value, so we do it the hard way */
+    infile = fopen("/etc/config/system.glGammaVal", "r");
+    if (infile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, infile);
+        fclose(infile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL)
+        rpng2_info.display_exponent = atof(p);
+    else
+        rpng2_info.display_exponent = default_display_exponent;
+
+
+    /* Now parse the command line for options and the PNG filename. */
+
+    while (*++argv && !error) {
+        if (!strncmp(*argv, "-display", 2)) {
+            if (!*++argv)
+                ++error;
+            else
+                displayname = *argv;
+        } else if (!strncmp(*argv, "-gamma", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                rpng2_info.display_exponent = atof(*argv);
+                if (rpng2_info.display_exponent <= 0.0)
+                    ++error;
+            }
+        } else if (!strncmp(*argv, "-bgcolor", 4)) {
+            if (!*++argv)
+                ++error;
+            else {
+                bgstr = *argv;
+                if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                    ++error;
+                else {
+                    have_bg = TRUE;
+                    bg_image = FALSE;
+                }
+            }
+        } else if (!strncmp(*argv, "-bgpat", 4)) {
+            if (!*++argv)
+                ++error;
+            else {
+                pat = atoi(*argv) - 1;
+                if (pat < 0 || pat >= num_bgpat)
+                    ++error;
+                else {
+                    bg_image = TRUE;
+                    have_bg = FALSE;
+                }
+            }
+        } else if (!strncmp(*argv, "-usleep", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                usleep_duration = (ulg)atol(*argv);
+                demo_timing = TRUE;
+            }
+        } else if (!strncmp(*argv, "-pause", 2)) {
+            pause_after_pass = TRUE;
+        } else if (!strncmp(*argv, "-timing", 2)) {
+            timing = TRUE;
+#if (defined(__i386__) || defined(_M_IX86))
+        } else if (!strncmp(*argv, "-nommxfilters", 7)) {
+            rpng2_info.nommxfilters = TRUE;
+        } else if (!strncmp(*argv, "-nommxcombine", 7)) {
+            rpng2_info.nommxcombine = TRUE;
+        } else if (!strncmp(*argv, "-nommxinterlace", 7)) {
+            rpng2_info.nommxinterlace = TRUE;
+        } else if (!strcmp(*argv, "-nommx")) {
+            rpng2_info.nommxfilters = TRUE;
+            rpng2_info.nommxcombine = TRUE;
+            rpng2_info.nommxinterlace = TRUE;
+#endif
+        } else {
+            if (**argv != '-') {
+                filename = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+    if (!filename) {
+        ++error;
+    } else if (!(infile = fopen(filename, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
+        ++error;
+    } else {
+        incount = fread(inbuf, 1, INBUFSIZE, infile);
+        if (incount < 8 || !readpng2_check_sig(inbuf, 8)) {
+            fprintf(stderr, PROGNAME
+              ":  [%s] is not a PNG file: incorrect signature\n",
+              filename);
+            ++error;
+        } else if ((rc = readpng2_init(&rpng2_info)) != 0) {
+            switch (rc) {
+                case 2:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] has bad IHDR (libpng longjmp)\n",
+                      filename);
+                    break;
+                case 4:
+                    fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                    break;
+                default:
+                    fprintf(stderr, PROGNAME
+                      ":  unknown readpng2_init() error\n");
+                    break;
+            }
+            ++error;
+        } else {
+            display = XOpenDisplay(displayname);
+            if (!display) {
+                readpng2_cleanup(&rpng2_info);
+                fprintf(stderr, PROGNAME ":  can't open X display [%s]\n",
+                  displayname? displayname : "default");
+                ++error;
+            }
+        }
+        if (error)
+            fclose(infile);
+    }
+
+
+    /* usage screen */
+
+    if (error) {
+        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);
+        readpng2_version_info();
+        fprintf(stderr, "\n"
+          "Usage:  %s [-display xdpy] [-gamma exp] [-bgcolor bg | -bgpat pat]\n"
+#if (defined(__i386__) || defined(_M_IX86))
+          "        %*s [[-nommxfilters] [-nommxcombine] [-nommxinterlace] | -nommx]\n"
+#endif
+          "        %*s [-usleep dur | -timing] [-pause] file.png\n\n"
+          "    xdpy\tname of the target X display (e.g., ``hostname:0'')\n"
+          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+          "\t\t  to the product of the lookup-table exponent (varies)\n"
+          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+          "    bg  \tdesired background color in 7-character hex RGB format\n"
+          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
+          "\t\t  used with transparent images; overrides -bgpat\n"
+          "    pat \tdesired background pattern number (1-%d); used with\n"
+          "\t\t  transparent images; overrides -bgcolor\n"
+#if (defined(__i386__) || defined(_M_IX86))
+          "    -nommx*\tdisable optimized MMX routines for decoding row filters,\n"
+          "\t\t  combining rows, and expanding interlacing, respectively\n"
+#endif
+          "    dur \tduration in microseconds to wait after displaying each\n"
+          "\t\t  row (for demo purposes)\n"
+          "    -timing\tenables delay for every block read, to simulate modem\n"
+          "\t\t  download of image (~36 Kbps)\n"
+          "    -pause\tpauses after displaying each pass until key pressed\n"
+          "\nPress Q, Esc or mouse button 1 (within image window, after image\n"
+          "is displayed) to quit.\n"
+          "\n", PROGNAME,
+#if (defined(__i386__) || defined(_M_IX86))
+          strlen(PROGNAME), " ",
+#endif
+          strlen(PROGNAME), " ", default_display_exponent, num_bgpat);
+        exit(1);
+    }
+
+
+    /* set the title-bar string, but make sure buffer doesn't overflow */
+
+    alen = strlen(appname);
+    flen = strlen(filename);
+    if (alen + flen + 3 > 1023)
+        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));
+    else
+        sprintf(titlebar, "%s:  %s", appname, filename);
+
+
+    /* set some final rpng2_info variables before entering main data loop */
+
+    if (have_bg) {
+        unsigned r, g, b;   /* this approach quiets compiler warnings */
+
+        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+        rpng2_info.bg_red   = (uch)r;
+        rpng2_info.bg_green = (uch)g;
+        rpng2_info.bg_blue  = (uch)b;
+    } else
+        rpng2_info.need_bgcolor = TRUE;
+
+    rpng2_info.done = FALSE;
+    rpng2_info.mainprog_init = rpng2_x_init;
+    rpng2_info.mainprog_display_row = rpng2_x_display_row;
+    rpng2_info.mainprog_finish_display = rpng2_x_finish_display;
+
+
+    /* OK, this is the fun part:  call readpng2_decode_data() at the start of
+     * the loop to deal with our first buffer of data (read in above to verify
+     * that the file is a PNG image), then loop through the file and continue
+     * calling the same routine to handle each chunk of data.  It in turn
+     * passes the data to libpng, which will invoke one or more of our call-
+     * backs as decoded data become available.  We optionally call sleep() for
+     * one second per iteration to simulate downloading the image via an analog
+     * modem. */
+
+    for (;;) {
+        Trace((stderr, "about to call readpng2_decode_data()\n"))
+        if (readpng2_decode_data(&rpng2_info, inbuf, incount))
+            ++error;
+        Trace((stderr, "done with readpng2_decode_data()\n"))
+        if (error || feof(infile) || rpng2_info.done)
+            break;
+        if (timing)
+            sleep(1);
+        incount = fread(inbuf, 1, INBUFSIZE, infile);
+    }
+
+
+    /* clean up PNG stuff and report any decoding errors */
+
+    fclose(infile);
+    Trace((stderr, "about to call readpng2_cleanup()\n"))
+    readpng2_cleanup(&rpng2_info);
+
+    if (error) {
+        fprintf(stderr, PROGNAME ":  libpng error while decoding PNG image\n");
+        exit(3);
+    }
+
+
+    /* wait for the user to tell us when to quit */
+
+    do
+        XNextEvent(display, &e);
+    while (!(e.type == ButtonPress && e.xbutton.button == Button1) &&
+           !(e.type == KeyPress &&    /*  v--- or 1 for shifted keys */
+             ((k = XLookupKeysym(&e.xkey, 0)) == XK_q || k == XK_Escape) ));
+
+
+    /* we're done:  clean up all image and X resources and go away */
+
+    Trace((stderr, "about to call rpng2_x_cleanup()\n"))
+    rpng2_x_cleanup();
+
+    return 0;
+}
+
+
+
+
+
+/* this function is called by readpng2_info_callback() in readpng2.c, which
+ * in turn is called by libpng after all of the pre-IDAT chunks have been
+ * read and processed--i.e., we now have enough info to finish initializing */
+
+static void rpng2_x_init(void)
+{
+    ulg i;
+    ulg rowbytes = rpng2_info.rowbytes;
+
+    Trace((stderr, "beginning rpng2_x_init()\n"))
+    Trace((stderr, "  rowbytes = %ld\n", rpng2_info.rowbytes))
+    Trace((stderr, "  width  = %ld\n", rpng2_info.width))
+    Trace((stderr, "  height = %ld\n", rpng2_info.height))
+
+    rpng2_info.image_data = (uch *)malloc(rowbytes * rpng2_info.height);
+    if (!rpng2_info.image_data) {
+        readpng2_cleanup(&rpng2_info);
+        return;
+    }
+
+    rpng2_info.row_pointers = (uch **)malloc(rpng2_info.height * sizeof(uch *));
+    if (!rpng2_info.row_pointers) {
+        free(rpng2_info.image_data);
+        rpng2_info.image_data = NULL;
+        readpng2_cleanup(&rpng2_info);
+        return;
+    }
+
+    for (i = 0;  i < rpng2_info.height;  ++i)
+        rpng2_info.row_pointers[i] = rpng2_info.image_data + i*rowbytes;
+
+
+    /* do the basic X initialization stuff, make the window, and fill it with
+     * the user-specified, file-specified or default background color or
+     * pattern */
+
+    if (rpng2_x_create_window()) {
+
+        /* GRR TEMPORARY HACK:  this is fundamentally no different from cases
+         * above; libpng should longjmp() back to us when png_ptr goes away.
+         * If we/it segfault instead, seems like a libpng bug... */
+
+        /* we're here via libpng callback, so if window fails, clean and bail */
+printf("readpng2_cleanup.\n");
+        readpng2_cleanup(&rpng2_info);
+        rpng2_x_cleanup();
+        exit(2);
+    }
+}
+
+
+
+
+
+static int rpng2_x_create_window(void)
+{
+    ulg bg_red   = rpng2_info.bg_red;
+    ulg bg_green = rpng2_info.bg_green;
+    ulg bg_blue  = rpng2_info.bg_blue;
+    ulg bg_pixel = 0L;
+    ulg attrmask;
+    int need_colormap = FALSE;
+    int screen, pad;
+    uch *xdata;
+    Window root;
+    XEvent e;
+    XGCValues gcvalues;
+    XSetWindowAttributes attr;
+    XSizeHints *size_hints;
+    XTextProperty windowName, *pWindowName = &windowName;
+    XTextProperty iconName, *pIconName = &iconName;
+    XVisualInfo visual_info;
+    XWMHints *wm_hints;
+
+
+    Trace((stderr, "beginning rpng2_x_create_window()\n"))
+
+    screen = DefaultScreen(display);
+    depth = DisplayPlanes(display, screen);
+    root = RootWindow(display, screen);
+
+#ifdef DEBUG
+    XSynchronize(display, True);
+#endif
+
+    if (depth != 16 && depth != 24 && depth != 32) {
+        int visuals_matched = 0;
+
+        Trace((stderr, "default depth is %d:  checking other visuals\n",
+          depth))
+
+        /* 24-bit first */
+        visual_info.screen = screen;
+        visual_info.depth = 24;
+        visual_list = XGetVisualInfo(display,
+          VisualScreenMask | VisualDepthMask, &visual_info, &visuals_matched);
+        if (visuals_matched == 0) {
+/* GRR:  add 15-, 16- and 32-bit TrueColor visuals (also DirectColor?) */
+            fprintf(stderr, "default screen depth %d not supported, and no"
+              " 24-bit visuals found\n", depth);
+            return 2;
+        }
+        Trace((stderr, "XGetVisualInfo() returned %d 24-bit visuals\n",
+          visuals_matched))
+        visual = visual_list[0].visual;
+        depth = visual_list[0].depth;
+/*
+        colormap_size = visual_list[0].colormap_size;
+        visual_class = visual->class;
+        visualID = XVisualIDFromVisual(visual);
+ */
+        have_nondefault_visual = TRUE;
+        need_colormap = TRUE;
+    } else {
+        XMatchVisualInfo(display, screen, depth, TrueColor, &visual_info);
+        visual = visual_info.visual;
+    }
+
+    RMask = visual->red_mask;
+    GMask = visual->green_mask;
+    BMask = visual->blue_mask;
+
+/* GRR:  add/check 8-bit support */
+    if (depth == 8 || need_colormap) {
+        colormap = XCreateColormap(display, root, visual, AllocNone);
+        if (!colormap) {
+            fprintf(stderr, "XCreateColormap() failed\n");
+            return 2;
+        }
+        have_colormap = TRUE;
+        if (depth == 8)
+            bg_image = FALSE;   /* gradient just wastes palette entries */
+    }
+    if (depth == 15 || depth == 16) {
+        RShift = 15 - rpng2_x_msb(RMask);    /* these are right-shifts */
+        GShift = 15 - rpng2_x_msb(GMask);
+        BShift = 15 - rpng2_x_msb(BMask);
+    } else if (depth > 16) {
+        RShift = rpng2_x_msb(RMask) - 7;     /* these are left-shifts */
+        GShift = rpng2_x_msb(GMask) - 7;
+        BShift = rpng2_x_msb(BMask) - 7;
+    }
+    if (depth >= 15 && (RShift < 0 || GShift < 0 || BShift < 0)) {
+        fprintf(stderr, "rpng2 internal logic error:  negative X shift(s)!\n");
+        return 2;
+    }
+
+/*---------------------------------------------------------------------------
+    Finally, create the window.
+  ---------------------------------------------------------------------------*/
+
+    attr.backing_store = Always;
+    attr.event_mask = ExposureMask | KeyPressMask | ButtonPressMask;
+    attrmask = CWBackingStore | CWEventMask;
+    if (have_nondefault_visual) {
+        attr.colormap = colormap;
+        attr.background_pixel = 0;
+        attr.border_pixel = 1;
+        attrmask |= CWColormap | CWBackPixel | CWBorderPixel;
+    }
+
+    window = XCreateWindow(display, root, 0, 0, rpng2_info.width,
+      rpng2_info.height, 0, depth, InputOutput, visual, attrmask, &attr);
+
+    if (window == None) {
+        fprintf(stderr, "XCreateWindow() failed\n");
+        return 2;
+    } else
+        have_window = TRUE;
+
+    if (depth == 8)
+        XSetWindowColormap(display, window, colormap);
+
+    if (!XStringListToTextProperty(&window_name, 1, pWindowName))
+        pWindowName = NULL;
+    if (!XStringListToTextProperty(&icon_name, 1, pIconName))
+        pIconName = NULL;
+
+    /* OK if either hints allocation fails; XSetWMProperties() allows NULLs */
+
+    if ((size_hints = XAllocSizeHints()) != NULL) {
+        /* window will not be resizable */
+        size_hints->flags = PMinSize | PMaxSize;
+        size_hints->min_width = size_hints->max_width = (int)rpng2_info.width;
+        size_hints->min_height = size_hints->max_height =
+          (int)rpng2_info.height;
+    }
+
+    if ((wm_hints = XAllocWMHints()) != NULL) {
+        wm_hints->initial_state = NormalState;
+        wm_hints->input = True;
+     /* wm_hints->icon_pixmap = icon_pixmap; */
+        wm_hints->flags = StateHint | InputHint  /* | IconPixmapHint */ ;
+    }
+
+    XSetWMProperties(display, window, pWindowName, pIconName, NULL, 0,
+      size_hints, wm_hints, NULL);
+
+    /* various properties and hints no longer needed; free memory */
+    if (pWindowName)
+       XFree(pWindowName->value);
+    if (pIconName)
+       XFree(pIconName->value);
+    if (size_hints)
+        XFree(size_hints);
+    if (wm_hints)
+       XFree(wm_hints);
+
+    XMapWindow(display, window);
+
+    gc = XCreateGC(display, window, 0, &gcvalues);
+    have_gc = TRUE;
+
+/*---------------------------------------------------------------------------
+    Allocate memory for the X- and display-specific version of the image.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        xdata = (uch *)malloc(4*rpng2_info.width*rpng2_info.height);
+        pad = 32;
+    } else if (depth == 16) {
+        xdata = (uch *)malloc(2*rpng2_info.width*rpng2_info.height);
+        pad = 16;
+    } else /* depth == 8 */ {
+        xdata = (uch *)malloc(rpng2_info.width*rpng2_info.height);
+        pad = 8;
+    }
+
+    if (!xdata) {
+        fprintf(stderr, PROGNAME ":  unable to allocate image memory\n");
+        return 4;
+    }
+
+    ximage = XCreateImage(display, visual, depth, ZPixmap, 0,
+      (char *)xdata, rpng2_info.width, rpng2_info.height, pad, 0);
+
+    if (!ximage) {
+        fprintf(stderr, PROGNAME ":  XCreateImage() failed\n");
+        free(xdata);
+        return 3;
+    }
+
+    /* to avoid testing the byte order every pixel (or doubling the size of
+     * the drawing routine with a giant if-test), we arbitrarily set the byte
+     * order to MSBFirst and let Xlib worry about inverting things on little-
+     * endian machines (e.g., Linux/x86, old VAXen, etc.)--this is not the
+     * most efficient approach (the giant if-test would be better), but in
+     * the interest of clarity, we'll take the easy way out... */
+
+    ximage->byte_order = MSBFirst;
+
+/*---------------------------------------------------------------------------
+    Fill window with the specified background color (default is black) or
+    faked "background image" (but latter is disabled if 8-bit; gradients
+    just waste palette entries).
+  ---------------------------------------------------------------------------*/
+
+    if (bg_image)
+        rpng2_x_load_bg_image();    /* resets bg_image if fails */
+
+    if (!bg_image) {
+        if (depth == 24 || depth == 32) {
+            bg_pixel = (bg_red   << RShift) |
+                       (bg_green << GShift) |
+                       (bg_blue  << BShift);
+        } else if (depth == 16) {
+            bg_pixel = (((bg_red   << 8) >> RShift) & RMask) |
+                       (((bg_green << 8) >> GShift) & GMask) |
+                       (((bg_blue  << 8) >> BShift) & BMask);
+        } else /* depth == 8 */ {
+
+            /* GRR:  add 8-bit support */
+
+        }
+        XSetForeground(display, gc, bg_pixel);
+        XFillRectangle(display, window, gc, 0, 0, rpng2_info.width,
+          rpng2_info.height);
+    }
+
+/*---------------------------------------------------------------------------
+    Wait for first Expose event to do any drawing, then flush and return.
+  ---------------------------------------------------------------------------*/
+
+    do
+        XNextEvent(display, &e);
+    while (e.type != Expose || e.xexpose.count);
+
+    XFlush(display);
+
+    return 0;
+
+} /* end function rpng2_x_create_window() */
+
+
+
+
+
+static int rpng2_x_load_bg_image(void)
+{
+    uch *src;
+    char *dest;
+    uch r1, r2, g1, g2, b1, b2;
+    uch r1_inv, r2_inv, g1_inv, g2_inv, b1_inv, b2_inv;
+    int k, hmax, max;
+    int xidx, yidx, yidx_max = (bgscale-1);
+    int even_odd_vert, even_odd_horiz, even_odd;
+    int invert_gradient2 = (bg[pat].type & 0x08);
+    int invert_column;
+    int ximage_rowbytes = ximage->bytes_per_line;
+    ulg i, row;
+    ulg pixel;
+
+/*---------------------------------------------------------------------------
+    Allocate buffer for fake background image to be used with transparent
+    images; if this fails, revert to plain background color.
+  ---------------------------------------------------------------------------*/
+
+    bg_rowbytes = 3 * rpng2_info.width;
+    bg_data = (uch *)malloc(bg_rowbytes * rpng2_info.height);
+    if (!bg_data) {
+        fprintf(stderr, PROGNAME
+          ":  unable to allocate memory for background image\n");
+        bg_image = 0;
+        return 1;
+    }
+
+/*---------------------------------------------------------------------------
+    Vertical gradients (ramps) in NxN squares, alternating direction and
+    colors (N == bgscale).
+  ---------------------------------------------------------------------------*/
+
+    if ((bg[pat].type & 0x07) == 0) {
+        uch r1_min  = rgb[bg[pat].rgb1_min].r;
+        uch g1_min  = rgb[bg[pat].rgb1_min].g;
+        uch b1_min  = rgb[bg[pat].rgb1_min].b;
+        uch r2_min  = rgb[bg[pat].rgb2_min].r;
+        uch g2_min  = rgb[bg[pat].rgb2_min].g;
+        uch b2_min  = rgb[bg[pat].rgb2_min].b;
+        int r1_diff = rgb[bg[pat].rgb1_max].r - r1_min;
+        int g1_diff = rgb[bg[pat].rgb1_max].g - g1_min;
+        int b1_diff = rgb[bg[pat].rgb1_max].b - b1_min;
+        int r2_diff = rgb[bg[pat].rgb2_max].r - r2_min;
+        int g2_diff = rgb[bg[pat].rgb2_max].g - g2_min;
+        int b2_diff = rgb[bg[pat].rgb2_max].b - b2_min;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            yidx = (int)(row % bgscale);
+            even_odd_vert = (int)((row / bgscale) & 1);
+
+            r1 = r1_min + (r1_diff * yidx) / yidx_max;
+            g1 = g1_min + (g1_diff * yidx) / yidx_max;
+            b1 = b1_min + (b1_diff * yidx) / yidx_max;
+            r1_inv = r1_min + (r1_diff * (yidx_max-yidx)) / yidx_max;
+            g1_inv = g1_min + (g1_diff * (yidx_max-yidx)) / yidx_max;
+            b1_inv = b1_min + (b1_diff * (yidx_max-yidx)) / yidx_max;
+
+            r2 = r2_min + (r2_diff * yidx) / yidx_max;
+            g2 = g2_min + (g2_diff * yidx) / yidx_max;
+            b2 = b2_min + (b2_diff * yidx) / yidx_max;
+            r2_inv = r2_min + (r2_diff * (yidx_max-yidx)) / yidx_max;
+            g2_inv = g2_min + (g2_diff * (yidx_max-yidx)) / yidx_max;
+            b2_inv = b2_min + (b2_diff * (yidx_max-yidx)) / yidx_max;
+
+            dest = (char *)bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                even_odd_horiz = (int)((i / bgscale) & 1);
+                even_odd = even_odd_vert ^ even_odd_horiz;
+                invert_column =
+                  (even_odd_horiz && (bg[pat].type & 0x10));
+                if (even_odd == 0) {        /* gradient #1 */
+                    if (invert_column) {
+                        *dest++ = r1_inv;
+                        *dest++ = g1_inv;
+                        *dest++ = b1_inv;
+                    } else {
+                        *dest++ = r1;
+                        *dest++ = g1;
+                        *dest++ = b1;
+                    }
+                } else {                    /* gradient #2 */
+                    if ((invert_column && invert_gradient2) ||
+                        (!invert_column && !invert_gradient2))
+                    {
+                        *dest++ = r2;       /* not inverted or */
+                        *dest++ = g2;       /*  doubly inverted */
+                        *dest++ = b2;
+                    } else {
+                        *dest++ = r2_inv;
+                        *dest++ = g2_inv;   /* singly inverted */
+                        *dest++ = b2_inv;
+                    }
+                }
+            }
+        }
+
+/*---------------------------------------------------------------------------
+    Soft gradient-diamonds with scale = bgscale.  Code contributed by Adam
+    M. Costello.
+  ---------------------------------------------------------------------------*/
+
+    } else if ((bg[pat].type & 0x07) == 1) {
+
+        hmax = (bgscale-1)/2;   /* half the max weight of a color */
+        max = 2*hmax;           /* the max weight of a color */
+
+        r1 = rgb[bg[pat].rgb1_max].r;
+        g1 = rgb[bg[pat].rgb1_max].g;
+        b1 = rgb[bg[pat].rgb1_max].b;
+        r2 = rgb[bg[pat].rgb2_max].r;
+        g2 = rgb[bg[pat].rgb2_max].g;
+        b2 = rgb[bg[pat].rgb2_max].b;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            yidx = (int)(row % bgscale);
+            if (yidx > hmax)
+                yidx = bgscale-1 - yidx;
+            dest = (char *)bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                xidx = (int)(i % bgscale);
+                if (xidx > hmax)
+                    xidx = bgscale-1 - xidx;
+                k = xidx + yidx;
+                *dest++ = (k*r1 + (max-k)*r2) / max;
+                *dest++ = (k*g1 + (max-k)*g2) / max;
+                *dest++ = (k*b1 + (max-k)*b2) / max;
+            }
+        }
+
+/*---------------------------------------------------------------------------
+    Radial "starburst" with azimuthal sinusoids; [eventually number of sinu-
+    soids will equal bgscale?].  This one is slow but very cool.  Code con-
+    tributed by Pieter S. van der Meulen (originally in Smalltalk).
+  ---------------------------------------------------------------------------*/
+
+    } else if ((bg[pat].type & 0x07) == 2) {
+        uch ch;
+        int ii, x, y, hw, hh, grayspot;
+        double freq, rotate, saturate, gray, intensity;
+        double angle=0.0, aoffset=0.0, maxDist, dist;
+        double red=0.0, green=0.0, blue=0.0, hue, s, v, f, p, q, t;
+
+        fprintf(stderr, "%s:  computing radial background...",
+          PROGNAME);
+        fflush(stderr);
+
+        hh = (int)(rpng2_info.height / 2);
+        hw = (int)(rpng2_info.width / 2);
+
+        /* variables for radial waves:
+         *   aoffset:  number of degrees to rotate hue [CURRENTLY NOT USED]
+         *   freq:  number of color beams originating from the center
+         *   grayspot:  size of the graying center area (anti-alias)
+         *   rotate:  rotation of the beams as a function of radius
+         *   saturate:  saturation of beams' shape azimuthally
+         */
+        angle = CLIP(angle, 0.0, 360.0);
+        grayspot = CLIP(bg[pat].bg_gray, 1, (hh + hw));
+        freq = MAX((double)bg[pat].bg_freq, 0.0);
+        saturate = (double)bg[pat].bg_bsat * 0.1;
+        rotate = (double)bg[pat].bg_brot * 0.1;
+        gray = 0.0;
+        intensity = 0.0;
+        maxDist = (double)((hw*hw) + (hh*hh));
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            y = (int)(row - hh);
+            dest = (char *)bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                x = (int)(i - hw);
+                angle = (x == 0)? PI_2 : atan((double)y / (double)x);
+                gray = (double)MAX(ABS(y), ABS(x)) / grayspot;
+                gray = MIN(1.0, gray);
+                dist = (double)((x*x) + (y*y)) / maxDist;
+                intensity = cos((angle+(rotate*dist*PI)) * freq) *
+                  gray * saturate;
+                intensity = (MAX(MIN(intensity,1.0),-1.0) + 1.0) * 0.5;
+                hue = (angle + PI) * INV_PI_360 + aoffset;
+                s = gray * ((double)(ABS(x)+ABS(y)) / (double)(hw + hh));
+                s = MIN(MAX(s,0.0), 1.0);
+                v = MIN(MAX(intensity,0.0), 1.0);
+
+                if (s == 0.0) {
+                    ch = (uch)(v * 255.0);
+                    *dest++ = ch;
+                    *dest++ = ch;
+                    *dest++ = ch;
+                } else {
+                    if ((hue < 0.0) || (hue >= 360.0))
+                        hue -= (((int)(hue / 360.0)) * 360.0);
+                    hue /= 60.0;
+                    ii = (int)hue;
+                    f = hue - (double)ii;
+                    p = (1.0 - s) * v;
+                    q = (1.0 - (s * f)) * v;
+                    t = (1.0 - (s * (1.0 - f))) * v;
+                    if      (ii == 0) { red = v; green = t; blue = p; }
+                    else if (ii == 1) { red = q; green = v; blue = p; }
+                    else if (ii == 2) { red = p; green = v; blue = t; }
+                    else if (ii == 3) { red = p; green = q; blue = v; }
+                    else if (ii == 4) { red = t; green = p; blue = v; }
+                    else if (ii == 5) { red = v; green = p; blue = q; }
+                    *dest++ = (uch)(red * 255.0);
+                    *dest++ = (uch)(green * 255.0);
+                    *dest++ = (uch)(blue * 255.0);
+                }
+            }
+        }
+        fprintf(stderr, "done.\n");
+        fflush(stderr);
+    }
+
+/*---------------------------------------------------------------------------
+    Blast background image to display buffer before beginning PNG decode.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        ulg red, green, blue;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            src = bg_data + row*bg_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                red   = *src++;
+                green = *src++;
+                blue  = *src++;
+                pixel = (red   << RShift) |
+                        (green << GShift) |
+                        (blue  << BShift);
+                /* recall that we set ximage->byte_order = MSBFirst above */
+                /* GRR BUG:  this assumes bpp == 32, but may be 24: */
+                *dest++ = (char)((pixel >> 24) & 0xff);
+                *dest++ = (char)((pixel >> 16) & 0xff);
+                *dest++ = (char)((pixel >>  8) & 0xff);
+                *dest++ = (char)( pixel        & 0xff);
+            }
+        }
+
+    } else if (depth == 16) {
+        ush red, green, blue;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            src = bg_data + row*bg_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                red   = ((ush)(*src) << 8);  ++src;
+                green = ((ush)(*src) << 8);  ++src;
+                blue  = ((ush)(*src) << 8);  ++src;
+                pixel = ((red   >> RShift) & RMask) |
+                        ((green >> GShift) & GMask) |
+                        ((blue  >> BShift) & BMask);
+                /* recall that we set ximage->byte_order = MSBFirst above */
+                *dest++ = (char)((pixel >>  8) & 0xff);
+                *dest++ = (char)( pixel        & 0xff);
+            }
+        }
+
+    } else /* depth == 8 */ {
+
+        /* GRR:  add 8-bit support */
+
+    }
+
+    XPutImage(display, window, gc, ximage, 0, 0, 0, 0, rpng2_info.width,
+      rpng2_info.height);
+
+    return 0;
+
+} /* end function rpng2_x_load_bg_image() */
+
+
+
+
+
+static void rpng2_x_display_row(ulg row)
+{
+    uch bg_red   = rpng2_info.bg_red;
+    uch bg_green = rpng2_info.bg_green;
+    uch bg_blue  = rpng2_info.bg_blue;
+    uch *src, *src2=NULL;
+    char *dest;
+    uch r, g, b, a;
+    int ximage_rowbytes = ximage->bytes_per_line;
+    ulg i, pixel;
+    static int rows=0, prevpass=(-1);
+    static ulg firstrow;
+
+/*---------------------------------------------------------------------------
+    rows and firstrow simply track how many rows (and which ones) have not
+    yet been displayed; alternatively, we could call XPutImage() for every
+    row and not bother with the records-keeping.
+  ---------------------------------------------------------------------------*/
+
+    Trace((stderr, "beginning rpng2_x_display_row()\n"))
+
+    if (rpng2_info.pass != prevpass) {
+        if (pause_after_pass && rpng2_info.pass > 0) {
+            XEvent e;
+            KeySym k;
+
+            fprintf(stderr,
+              "%s:  end of pass %d of 7; click in image window to continue\n",
+              PROGNAME, prevpass + 1);
+            do
+                XNextEvent(display, &e);
+            while (!(e.type == ButtonPress && e.xbutton.button == Button1)
+                   && !(e.type == KeyPress &&
+                   ((k = XLookupKeysym(&e.xkey, 0)) == XK_q
+                    || k == XK_Escape) )) ;
+        }
+        fprintf(stderr, "%s:  pass %d of 7\r", PROGNAME, rpng2_info.pass + 1);
+        fflush(stderr);
+        prevpass = rpng2_info.pass;
+    }
+
+    if (rows == 0)
+        firstrow = row;   /* first row that is not yet displayed */
+
+    ++rows;   /* count of rows received but not yet displayed */
+
+/*---------------------------------------------------------------------------
+    Aside from the use of the rpng2_info struct, the lack of an outer loop
+    (over rows) and moving the XPutImage() call outside the "if (depth)"
+    tests, this routine is identical to rpng_x_display_image() in the non-
+    progressive version of the program.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        ulg red, green, blue;
+
+        src = rpng2_info.image_data + row*rpng2_info.rowbytes;
+        if (bg_image)
+            src2 = bg_data + row*bg_rowbytes;
+        dest = ximage->data + row*ximage_rowbytes;
+        if (rpng2_info.channels == 3) {
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                red   = *src++;
+                green = *src++;
+                blue  = *src++;
+                pixel = (red   << RShift) |
+                        (green << GShift) |
+                        (blue  << BShift);
+                /* recall that we set ximage->byte_order = MSBFirst above */
+                /* GRR BUG:  this assumes bpp == 32, but may be 24: */
+                *dest++ = (char)((pixel >> 24) & 0xff);
+                *dest++ = (char)((pixel >> 16) & 0xff);
+                *dest++ = (char)((pixel >>  8) & 0xff);
+                *dest++ = (char)( pixel        & 0xff);
+            }
+        } else /* if (rpng2_info.channels == 4) */ {
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                a = *src++;
+                if (bg_image) {
+                    bg_red   = *src2++;
+                    bg_green = *src2++;
+                    bg_blue  = *src2++;
+                }
+                if (a == 255) {
+                    red   = r;
+                    green = g;
+                    blue  = b;
+                } else if (a == 0) {
+                    red   = bg_red;
+                    green = bg_green;
+                    blue  = bg_blue;
+                } else {
+                    /* this macro (from png.h) composites the foreground
+                     * and background values and puts the result into the
+                     * first argument */
+                    alpha_composite(red,   r, a, bg_red);
+                    alpha_composite(green, g, a, bg_green);
+                    alpha_composite(blue,  b, a, bg_blue);
+                }
+                pixel = (red   << RShift) |
+                        (green << GShift) |
+                        (blue  << BShift);
+                /* recall that we set ximage->byte_order = MSBFirst above */
+                /* GRR BUG:  this assumes bpp == 32, but may be 24: */
+                *dest++ = (char)((pixel >> 24) & 0xff);
+                *dest++ = (char)((pixel >> 16) & 0xff);
+                *dest++ = (char)((pixel >>  8) & 0xff);
+                *dest++ = (char)( pixel        & 0xff);
+            }
+        }
+
+    } else if (depth == 16) {
+        ush red, green, blue;
+
+        src = rpng2_info.row_pointers[row];
+        if (bg_image)
+            src2 = bg_data + row*bg_rowbytes;
+        dest = ximage->data + row*ximage_rowbytes;
+        if (rpng2_info.channels == 3) {
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                red   = ((ush)(*src) << 8);
+                ++src;
+                green = ((ush)(*src) << 8);
+                ++src;
+                blue  = ((ush)(*src) << 8);
+                ++src;
+                pixel = ((red   >> RShift) & RMask) |
+                        ((green >> GShift) & GMask) |
+                        ((blue  >> BShift) & BMask);
+                /* recall that we set ximage->byte_order = MSBFirst above */
+                *dest++ = (char)((pixel >>  8) & 0xff);
+                *dest++ = (char)( pixel        & 0xff);
+            }
+        } else /* if (rpng2_info.channels == 4) */ {
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                a = *src++;
+                if (bg_image) {
+                    bg_red   = *src2++;
+                    bg_green = *src2++;
+                    bg_blue  = *src2++;
+                }
+                if (a == 255) {
+                    red   = ((ush)r << 8);
+                    green = ((ush)g << 8);
+                    blue  = ((ush)b << 8);
+                } else if (a == 0) {
+                    red   = ((ush)bg_red   << 8);
+                    green = ((ush)bg_green << 8);
+                    blue  = ((ush)bg_blue  << 8);
+                } else {
+                    /* this macro (from png.h) composites the foreground
+                     * and background values and puts the result back into
+                     * the first argument (== fg byte here:  safe) */
+                    alpha_composite(r, r, a, bg_red);
+                    alpha_composite(g, g, a, bg_green);
+                    alpha_composite(b, b, a, bg_blue);
+                    red   = ((ush)r << 8);
+                    green = ((ush)g << 8);
+                    blue  = ((ush)b << 8);
+                }
+                pixel = ((red   >> RShift) & RMask) |
+                        ((green >> GShift) & GMask) |
+                        ((blue  >> BShift) & BMask);
+                /* recall that we set ximage->byte_order = MSBFirst above */
+                *dest++ = (char)((pixel >>  8) & 0xff);
+                *dest++ = (char)( pixel        & 0xff);
+            }
+        }
+
+    } else /* depth == 8 */ {
+
+        /* GRR:  add 8-bit support */
+
+    }
+
+
+/*---------------------------------------------------------------------------
+    Display after every 16 rows or when on one of last two rows.  (Region
+    may include previously displayed lines due to interlacing--i.e., not
+    contiguous.  Also, second-to-last row is final one in interlaced images
+    with odd number of rows.)  For demos, flush (and delay) after every 16th
+    row so "sparse" passes don't go twice as fast.
+  ---------------------------------------------------------------------------*/
+
+    if (demo_timing && (row - firstrow >= 16 || row >= rpng2_info.height-2)) {
+        XPutImage(display, window, gc, ximage, 0, (int)firstrow, 0,
+          (int)firstrow, rpng2_info.width, row - firstrow + 1);
+        XFlush(display);
+        rows = 0;
+        usleep(usleep_duration);
+    } else
+    if (!demo_timing && ((rows & 0xf) == 0 || row >= rpng2_info.height-2)) {
+        XPutImage(display, window, gc, ximage, 0, (int)firstrow, 0,
+          (int)firstrow, rpng2_info.width, row - firstrow + 1);
+        XFlush(display);
+        rows = 0;
+    }
+
+}
+
+
+
+
+
+static void rpng2_x_finish_display(void)
+{
+    Trace((stderr, "beginning rpng2_x_finish_display()\n"))
+
+    /* last row has already been displayed by rpng2_x_display_row(), so we
+     * have nothing to do here except set a flag and let the user know that
+     * the image is done */
+
+    rpng2_info.done = TRUE;
+    printf(
+      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n");
+    fflush(stdout);
+}
+
+
+
+
+
+static void rpng2_x_cleanup(void)
+{
+    if (bg_image && bg_data) {
+        free(bg_data);
+        bg_data = NULL;
+    }
+
+    if (rpng2_info.image_data) {
+        free(rpng2_info.image_data);
+        rpng2_info.image_data = NULL;
+    }
+
+    if (rpng2_info.row_pointers) {
+        free(rpng2_info.row_pointers);
+        rpng2_info.row_pointers = NULL;
+    }
+
+    if (ximage) {
+        if (ximage->data) {
+            free(ximage->data);           /* we allocated it, so we free it */
+            ximage->data = (char *)NULL;  /*  instead of XDestroyImage() */
+        }
+        XDestroyImage(ximage);
+        ximage = NULL;
+    }
+
+    if (have_gc)
+        XFreeGC(display, gc);
+
+    if (have_window)
+        XDestroyWindow(display, window);
+
+    if (have_colormap)
+        XFreeColormap(display, colormap);
+
+    if (have_nondefault_visual)
+        XFree(visual_list);
+}
+
+
+
+
+
+static int rpng2_x_msb(ulg u32val)
+{
+    int i;
+
+    for (i = 31;  i >= 0;  --i) {
+        if (u32val & 0x80000000L)
+            break;
+        u32val <<= 1;
+    }
+    return i;
+}
diff --git a/gs/libpng/contrib/gregbook/toucan.png b/gs/libpng/contrib/gregbook/toucan.png
new file mode 100644
index 000000000..03960d493
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/toucan.png
diff --git a/gs/libpng/contrib/gregbook/wpng.c b/gs/libpng/contrib/gregbook/wpng.c
new file mode 100644
index 000000000..d6e85148b
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/wpng.c
@@ -0,0 +1,816 @@
+/*---------------------------------------------------------------------------
+
+   wpng - simple PNG-writing program                                 wpng.c
+
+   This program converts certain NetPBM binary files (grayscale and RGB,
+   maxval = 255) to PNG.  Non-interlaced PNGs are written progressively;
+   interlaced PNGs are read and written in one memory-intensive blast.
+   Thanks to Jean-loup Gailly for providing the necessary trick to read
+   interactive text from the keyboard while stdin is redirected.
+
+   NOTE:  includes provisional support for PNM type "8" (portable alphamap)
+          images, presumed to be a 32-bit interleaved RGBA format; no pro-
+          vision for possible interleaved grayscale+alpha (16-bit) format.
+          THIS IS UNLIKELY TO BECOME AN OFFICIAL NETPBM ALPHA FORMAT!
+
+   to do:
+    - delete output file if quit before calling any writepng routines
+    - process backspace with -text option under DOS/Win? (currently get ^H)
+
+  ---------------------------------------------------------------------------
+
+   Changelog:
+    - 1.01:  initial public release
+    - 1.02:  modified to allow abbreviated options
+    - 1.03:  removed extraneous character from usage screen; fixed bug in
+              command-line parsing
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2000 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "wpng"
+#define VERSION   "1.03 of 19 March 2000"
+#define APPNAME   "Simple PGM/PPM/PAM to PNG Converter"
+
+#if defined(__MSDOS__) || defined(__OS2__)
+#  define DOS_OS2_W32
+#elif defined(_WIN32) || defined(__WIN32__)
+#  define DOS_OS2_W32
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <setjmp.h>     /* for jmpbuf declaration in writepng.h */
+#include <time.h>
+
+#ifdef DOS_OS2_W32
+#  include <io.h>       /* for isatty(), setmode() prototypes */
+#  include <fcntl.h>    /* O_BINARY for fdopen() without text translation */
+#  ifdef __EMX__
+#    ifndef getch
+#      define getch() _read_kbd(0, 1, 0)    /* need getche() */
+#    endif
+#  else /* !__EMX__ */
+#    ifdef __GO32__
+#      include <pc.h>
+#      define getch() getkey()  /* GRR:  need getche() */
+#    else
+#      include <conio.h>        /* for getche() console input */
+#    endif
+#  endif /* ?__EMX__ */
+#  define FGETS(buf,len,stream)  dos_kbd_gets(buf,len)
+#else
+#  include <unistd.h>           /* for isatty() prototype */
+#  define FGETS fgets
+#endif
+
+/* #define DEBUG  :  this enables the Trace() macros */
+
+/* #define FORBID_LATIN1_CTRL  :  this requires the user to re-enter any
+   text that includes control characters discouraged by the PNG spec; text
+   that includes an escape character (27) must be re-entered regardless */
+
+#include "writepng.h"   /* typedefs, common macros, writepng prototypes */
+
+
+
+/* local prototypes */
+
+static int  wpng_isvalid_latin1(uch *p, int len);
+static void wpng_cleanup(void);
+
+#ifdef DOS_OS2_W32
+   static char *dos_kbd_gets(char *buf, int len);
+#endif
+
+
+
+static mainprog_info wpng_info;   /* lone global */
+
+
+
+int main(int argc, char **argv)
+{
+#ifndef DOS_OS2_W32
+    FILE *keybd;
+#endif
+#ifdef sgi
+    FILE *tmpfile;      /* or we could just use keybd, since no overlap */
+    char tmpline[80];
+#endif
+    char *inname = NULL, outname[256];
+    char *p, pnmchar, pnmline[256];
+    char *bgstr, *textbuf = NULL;
+    ulg rowbytes;
+    int rc, len = 0;
+    int error = 0;
+    int text = FALSE;
+    int maxval;
+    double LUT_exponent;                /* just the lookup table */
+    double CRT_exponent = 2.2;          /* just the monitor */
+    double default_display_exponent;    /* whole display system */
+    double default_gamma = 0.0;
+
+
+    wpng_info.infile = NULL;
+    wpng_info.outfile = NULL;
+    wpng_info.image_data = NULL;
+    wpng_info.row_pointers = NULL;
+    wpng_info.filter = FALSE;
+    wpng_info.interlaced = FALSE;
+    wpng_info.have_bg = FALSE;
+    wpng_info.have_time = FALSE;
+    wpng_info.have_text = 0;
+    wpng_info.gamma = 0.0;
+
+
+    /* First get the default value for our display-system exponent, i.e.,
+     * the product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  If the PNM image
+     * looks correct on the user's display system, its file gamma is the
+     * inverse of this value.  (Note that this is not an exhaustive list
+     * of LUT values--e.g., OpenStep has a lot of weird ones--but it should
+     * cover 99% of the current possibilities.  This section must ensure
+     * that default_display_exponent is positive.) */
+
+#if defined(NeXT)
+    /* third-party utilities can modify the default LUT exponent */
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to
+     * get the "gamma" value, so we do it the hard way */
+    tmpfile = fopen("/etc/config/system.glGammaVal", "r");
+    if (tmpfile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, tmpfile);
+        fclose(tmpfile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL) {
+        double exponent = atof(p);
+
+        if (exponent > 0.0)
+            default_gamma = 1.0 / exponent;
+    }
+
+    if (default_gamma == 0.0)
+        default_gamma = 1.0 / default_display_exponent;
+
+
+    /* Now parse the command line for options and the PNM filename. */
+
+    while (*++argv && !error) {
+        if (!strncmp(*argv, "-i", 2)) {
+            wpng_info.interlaced = TRUE;
+        } else if (!strncmp(*argv, "-time", 3)) {
+            wpng_info.modtime = time(NULL);
+            wpng_info.have_time = TRUE;
+        } else if (!strncmp(*argv, "-text", 3)) {
+            text = TRUE;
+        } else if (!strncmp(*argv, "-gamma", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                wpng_info.gamma = atof(*argv);
+                if (wpng_info.gamma <= 0.0)
+                    ++error;
+                else if (wpng_info.gamma > 1.01)
+                    fprintf(stderr, PROGNAME
+                      " warning:  file gammas are usually less than 1.0\n");
+            }
+        } else if (!strncmp(*argv, "-bgcolor", 4)) {
+            if (!*++argv)
+                ++error;
+            else {
+                bgstr = *argv;
+                if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                    ++error;
+                else {
+                    unsigned r, g, b;  /* this way quiets compiler warnings */
+
+                    sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+                    wpng_info.bg_red   = (uch)r;
+                    wpng_info.bg_green = (uch)g;
+                    wpng_info.bg_blue  = (uch)b;
+                    wpng_info.have_bg = TRUE;
+                }
+            }
+        } else {
+            if (**argv != '-') {
+                inname = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+
+    /* open the input and output files, or register an error and abort */
+
+    if (!inname) {
+        if (isatty(0)) {
+            fprintf(stderr, PROGNAME
+              ":  must give input filename or provide image data via stdin\n");
+            ++error;
+        } else {
+#ifdef DOS_OS2_W32
+            /* some buggy C libraries require BOTH setmode() and fdopen(bin) */
+            setmode(fileno(stdin), O_BINARY);
+            setmode(fileno(stdout), O_BINARY);
+#endif
+            if ((wpng_info.infile = fdopen(fileno(stdin), "rb")) == NULL) {
+                fprintf(stderr, PROGNAME
+                  ":  unable to reopen stdin in binary mode\n");
+                ++error;
+            } else
+            if ((wpng_info.outfile = fdopen(fileno(stdout), "wb")) == NULL) {
+                fprintf(stderr, PROGNAME
+                  ":  unable to reopen stdout in binary mode\n");
+                fclose(wpng_info.infile);
+                ++error;
+            } else
+                wpng_info.filter = TRUE;
+        }
+    } else if ((len = strlen(inname)) > 250) {
+        fprintf(stderr, PROGNAME ":  input filename is too long [%d chars]\n",
+          len);
+        ++error;
+    } else if (!(wpng_info.infile = fopen(inname, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open input file [%s]\n", inname);
+        ++error;
+    }
+
+    if (!error) {
+        fgets(pnmline, 256, wpng_info.infile);
+        if (pnmline[0] != 'P' || ((pnmchar = pnmline[1]) != '5' &&
+            pnmchar != '6' && pnmchar != '8'))
+        {
+            fprintf(stderr, PROGNAME
+              ":  input file [%s] is not a binary PGM, PPM or PAM file\n",
+              inname);
+            ++error;
+        } else {
+            wpng_info.pnmtype = (int)(pnmchar - '0');
+            if (wpng_info.pnmtype != 8)
+                wpng_info.have_bg = FALSE;  /* no need for bg if opaque */
+            do {
+                fgets(pnmline, 256, wpng_info.infile);  /* lose any comments */
+            } while (pnmline[0] == '#');
+            sscanf(pnmline, "%ld %ld", &wpng_info.width, &wpng_info.height);
+            do {
+                fgets(pnmline, 256, wpng_info.infile);  /* more comment lines */
+            } while (pnmline[0] == '#');
+            sscanf(pnmline, "%d", &maxval);
+            if (wpng_info.width <= 0L || wpng_info.height <= 0L ||
+                maxval != 255)
+            {
+                fprintf(stderr, PROGNAME
+                  ":  only positive width/height, maxval == 255 allowed \n");
+                ++error;
+            }
+            wpng_info.sample_depth = 8;  /* <==> maxval 255 */
+
+            if (!wpng_info.filter) {
+                /* make outname from inname */
+                if ((p = strrchr(inname, '.')) == NULL ||
+                    (p - inname) != (len - 4))
+                {
+                    strcpy(outname, inname);
+                    strcpy(outname+len, ".png");
+                } else {
+                    len -= 4;
+                    strncpy(outname, inname, len);
+                    strcpy(outname+len, ".png");
+                }
+                /* check if outname already exists; if not, open */
+                if ((wpng_info.outfile = fopen(outname, "rb")) != NULL) {
+                    fprintf(stderr, PROGNAME ":  output file exists [%s]\n",
+                      outname);
+                    fclose(wpng_info.outfile);
+                    ++error;
+                } else if (!(wpng_info.outfile = fopen(outname, "wb"))) {
+                    fprintf(stderr, PROGNAME ":  can't open output file [%s]\n",
+                      outname);
+                    ++error;
+                }
+            }
+        }
+        if (error) {
+            fclose(wpng_info.infile);
+            wpng_info.infile = NULL;
+            if (wpng_info.filter) {
+                fclose(wpng_info.outfile);
+                wpng_info.outfile = NULL;
+            }
+        }
+    }
+
+
+    /* if we had any errors, print usage and die horrible death...arrr! */
+
+    if (error) {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, APPNAME);
+        writepng_version_info();
+        fprintf(stderr, "\n"
+"Usage:  %s [-gamma exp] [-bgcolor bg] [-text] [-time] [-interlace] pnmfile\n"
+"or: ... | %s [-gamma exp] [-bgcolor bg] [-text] [-time] [-interlace] | ...\n"
+         "    exp \ttransfer-function exponent (``gamma'') of the image in\n"
+         "\t\t  floating-point format (e.g., ``%.5f''); if image looks\n"
+         "\t\t  correct on given display system, image gamma is equal to\n"
+         "\t\t  inverse of display-system exponent, i.e., 1 / (LUT * CRT)\n"
+         "\t\t  (where LUT = lookup-table exponent and CRT = CRT exponent;\n"
+         "\t\t  first varies, second is usually 2.2, all are positive)\n"
+         "    bg  \tdesired background color for alpha-channel images, in\n"
+         "\t\t  7-character hex RGB format (e.g., ``#ff7700'' for orange:\n"
+         "\t\t  same as HTML colors)\n"
+         "    -text\tprompt interactively for text info (tEXt chunks)\n"
+         "    -time\tinclude a tIME chunk (last modification time)\n"
+         "    -interlace\twrite interlaced PNG image\n"
+         "\n"
+"pnmfile or stdin must be a binary PGM (`P5'), PPM (`P6') or (extremely\n"
+"unofficial and unsupported!) PAM (`P8') file.  Currently it is required\n"
+"to have maxval == 255 (i.e., no scaling).  If pnmfile is specified, it\n"
+"is converted to the corresponding PNG file with the same base name but a\n"
+"``.png'' extension; files read from stdin are converted and sent to stdout.\n"
+"The conversion is progressive (low memory usage) unless interlacing is\n"
+"requested; in that case the whole image will be buffered in memory and\n"
+"written in one call.\n"
+         "\n", PROGNAME, PROGNAME, default_gamma);
+        exit(1);
+    }
+
+
+    /* prepare the text buffers for libpng's use; note that even though
+     * PNG's png_text struct includes a length field, we don't have to fill
+     * it out */
+
+    if (text &&
+#ifndef DOS_OS2_W32
+        (keybd = fdopen(fileno(stderr), "r")) != NULL &&
+#endif
+        (textbuf = (char *)malloc((5 + 9)*75)) != NULL)
+    {
+        int i, valid, result;
+
+        fprintf(stderr,
+          "Enter text info (no more than 72 characters per line);\n");
+        fprintf(stderr, "to skip a field, hit the <Enter> key.\n");
+        /* note:  just <Enter> leaves len == 1 */
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_TITLE_OFFSET;
+            fprintf(stderr, "  Title: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.title = p;
+                wpng_info.have_text |= TEXT_TITLE;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_TITLE;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_TITLE;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_AUTHOR_OFFSET;
+            fprintf(stderr, "  Author: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.author = p;
+                wpng_info.have_text |= TEXT_AUTHOR;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_AUTHOR;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_AUTHOR;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_DESC_OFFSET;
+            fprintf(stderr, "  Description (up to 9 lines):\n");
+            for (i = 1;  i < 10;  ++i) {
+                fprintf(stderr, "    [%d] ", i);
+                fflush(stderr);
+                if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1)
+                    p += len;   /* now points at NULL; char before is newline */
+                else
+                    break;
+            }
+            if ((len = p - (textbuf + TEXT_DESC_OFFSET)) > 1) {
+                if (p[-1] == '\n') {
+                    p[-1] = '\0';
+                    --len;
+                }
+                wpng_info.desc = textbuf + TEXT_DESC_OFFSET;
+                wpng_info.have_text |= TEXT_DESC;
+                p = textbuf + TEXT_DESC_OFFSET;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_DESC;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_DESC;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_COPY_OFFSET;
+            fprintf(stderr, "  Copyright: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.copyright = p;
+                wpng_info.have_text |= TEXT_COPY;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_COPY;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_COPY;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_EMAIL_OFFSET;
+            fprintf(stderr, "  E-mail: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.email = p;
+                wpng_info.have_text |= TEXT_EMAIL;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_EMAIL;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_EMAIL;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_URL_OFFSET;
+            fprintf(stderr, "  URL: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.url = p;
+                wpng_info.have_text |= TEXT_URL;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_URL;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_URL;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+#ifndef DOS_OS2_W32
+        fclose(keybd);
+#endif
+
+    } else if (text) {
+        fprintf(stderr, PROGNAME ":  unable to allocate memory for text\n");
+        text = FALSE;
+        wpng_info.have_text = 0;
+    }
+
+
+    /* allocate libpng stuff, initialize transformations, write pre-IDAT data */
+
+    if ((rc = writepng_init(&wpng_info)) != 0) {
+        switch (rc) {
+            case 2:
+                fprintf(stderr, PROGNAME
+                  ":  libpng initialization problem (longjmp)\n");
+                break;
+            case 4:
+                fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                break;
+            case 11:
+                fprintf(stderr, PROGNAME
+                  ":  internal logic error (unexpected PNM type)\n");
+                break;
+            default:
+                fprintf(stderr, PROGNAME
+                  ":  unknown writepng_init() error\n");
+                break;
+        }
+        exit(rc);
+    }
+
+
+    /* free textbuf, since it's a completely local variable and all text info
+     * has just been written to the PNG file */
+
+    if (text && textbuf) {
+        free(textbuf);
+        textbuf = NULL;
+    }
+
+
+    /* calculate rowbytes on basis of image type; note that this becomes much
+     * more complicated if we choose to support PBM type, ASCII PNM types, or
+     * 16-bit-per-sample binary data [currently not an official NetPBM type] */
+
+    if (wpng_info.pnmtype == 5)
+        rowbytes = wpng_info.width;
+    else if (wpng_info.pnmtype == 6)
+        rowbytes = wpng_info.width * 3;
+    else /* if (wpng_info.pnmtype == 8) */
+        rowbytes = wpng_info.width * 4;
+
+
+    /* read and write the image, either in its entirety (if writing interlaced
+     * PNG) or row by row (if non-interlaced) */
+
+    fprintf(stderr, "Encoding image data...\n");
+    fflush(stderr);
+
+    if (wpng_info.interlaced) {
+        long i;
+        ulg bytes;
+        ulg image_bytes = rowbytes * wpng_info.height;   /* overflow? */
+
+        wpng_info.image_data = (uch *)malloc(image_bytes);
+        wpng_info.row_pointers = (uch **)malloc(wpng_info.height*sizeof(uch *));
+        if (wpng_info.image_data == NULL || wpng_info.row_pointers == NULL) {
+            fprintf(stderr, PROGNAME ":  insufficient memory for image data\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(5);
+        }
+        for (i = 0;  i < wpng_info.height;  ++i)
+            wpng_info.row_pointers[i] = wpng_info.image_data + i*rowbytes;
+        bytes = fread(wpng_info.image_data, 1, image_bytes, wpng_info.infile);
+        if (bytes != image_bytes) {
+            fprintf(stderr, PROGNAME ":  expected %lu bytes, got %lu bytes\n",
+              image_bytes, bytes);
+            fprintf(stderr, "  (continuing anyway)\n");
+        }
+        if (writepng_encode_image(&wpng_info) != 0) {
+            fprintf(stderr, PROGNAME
+              ":  libpng problem (longjmp) while writing image data\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(2);
+        }
+
+    } else /* not interlaced:  write progressively (row by row) */ {
+        long j;
+        ulg bytes;
+
+        wpng_info.image_data = (uch *)malloc(rowbytes);
+        if (wpng_info.image_data == NULL) {
+            fprintf(stderr, PROGNAME ":  insufficient memory for row data\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(5);
+        }
+        error = 0;
+        for (j = wpng_info.height;  j > 0L;  --j) {
+            bytes = fread(wpng_info.image_data, 1, rowbytes, wpng_info.infile);
+            if (bytes != rowbytes) {
+                fprintf(stderr, PROGNAME
+                  ":  expected %lu bytes, got %lu bytes (row %ld)\n", rowbytes,
+                  bytes, wpng_info.height-j);
+                ++error;
+                break;
+            }
+            if (writepng_encode_row(&wpng_info) != 0) {
+                fprintf(stderr, PROGNAME
+                  ":  libpng problem (longjmp) while writing row %ld\n",
+                  wpng_info.height-j);
+                ++error;
+                break;
+            }
+        }
+        if (error) {
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(2);
+        }
+        if (writepng_encode_finish(&wpng_info) != 0) {
+            fprintf(stderr, PROGNAME ":  error on final libpng call\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(2);
+        }
+    }
+
+
+    /* OK, we're done (successfully):  clean up all resources and quit */
+
+    fprintf(stderr, "Done.\n");
+    fflush(stderr);
+
+    writepng_cleanup(&wpng_info);
+    wpng_cleanup();
+
+    return 0;
+}
+
+
+
+
+
+static int wpng_isvalid_latin1(uch *p, int len)
+{
+    int i, result = -1;
+
+    for (i = 0;  i < len;  ++i) {
+        if (p[i] == 10 || (p[i] > 31 && p[i] < 127) || p[i] > 160)
+            continue;           /* character is completely OK */
+        if (result < 0 || (p[result] != 27 && p[i] == 27))
+            result = i;         /* mark location of first questionable one */
+    }                           /*  or of first escape character (bad) */
+
+    return result;
+}
+
+
+
+
+
+static void wpng_cleanup(void)
+{
+    if (wpng_info.outfile) {
+        fclose(wpng_info.outfile);
+        wpng_info.outfile = NULL;
+    }
+
+    if (wpng_info.infile) {
+        fclose(wpng_info.infile);
+        wpng_info.infile = NULL;
+    }
+
+    if (wpng_info.image_data) {
+        free(wpng_info.image_data);
+        wpng_info.image_data = NULL;
+    }
+
+    if (wpng_info.row_pointers) {
+        free(wpng_info.row_pointers);
+        wpng_info.row_pointers = NULL;
+    }
+}
+
+
+
+
+#ifdef DOS_OS2_W32
+
+static char *dos_kbd_gets(char *buf, int len)
+{
+    int ch, count=0;
+
+    do {
+        buf[count++] = ch = getche();
+    } while (ch != '\r' && count < len-1);
+
+    buf[count--] = '\0';        /* terminate string */
+    if (buf[count] == '\r')     /* Enter key makes CR, so change to newline */
+        buf[count] = '\n';
+
+    fprintf(stderr, "\n");      /* Enter key does *not* cause a newline */
+    fflush(stderr);
+
+    return buf;
+}
+
+#endif /* DOS_OS2_W32 */
diff --git a/gs/libpng/contrib/gregbook/writepng.c b/gs/libpng/contrib/gregbook/writepng.c
new file mode 100644
index 000000000..6802b12fb
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/writepng.c
@@ -0,0 +1,368 @@
+/*---------------------------------------------------------------------------
+
+   wpng - simple PNG-writing program                             writepng.c
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2000 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+
+#include <stdlib.h>     /* for exit() prototype */
+
+#include "png.h"        /* libpng header; includes zlib.h and setjmp.h */
+#include "writepng.h"   /* typedefs, common macros, public prototypes */
+
+
+/* local prototype */
+
+static void writepng_error_handler(png_structp png_ptr, png_const_charp msg);
+
+
+
+void writepng_version_info(void)
+{
+  fprintf(stderr, "   Compiled with libpng %s; using libpng %s.\n",
+    PNG_LIBPNG_VER_STRING, png_libpng_ver);
+  fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",
+    ZLIB_VERSION, zlib_version);
+}
+
+
+
+
+/* returns 0 for success, 2 for libpng problem, 4 for out of memory, 11 for
+ *  unexpected pnmtype; note that outfile might be stdout */
+
+int writepng_init(mainprog_info *mainprog_ptr)
+{
+    png_structp  png_ptr;       /* note:  temporary variables! */
+    png_infop  info_ptr;
+    int color_type, interlace_type;
+
+
+    /* could also replace libpng warning-handler (final NULL), but no need: */
+
+    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,
+      writepng_error_handler, NULL);
+    if (!png_ptr)
+        return 4;   /* out of memory */
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        png_destroy_write_struct(&png_ptr, NULL);
+        return 4;   /* out of memory */
+    }
+
+
+    /* setjmp() must be called in every function that calls a PNG-writing
+     * libpng function, unless an alternate error handler was installed--
+     * but compatible error handlers must either use longjmp() themselves
+     * (as in this program) or exit immediately, so here we go: */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        return 2;
+    }
+
+
+    /* make sure outfile is (re)opened in BINARY mode */
+
+    png_init_io(png_ptr, mainprog_ptr->outfile);
+
+
+    /* set the compression levels--in general, always want to leave filtering
+     * turned on (except for palette images) and allow all of the filters,
+     * which is the default; want 32K zlib window, unless entire image buffer
+     * is 16K or smaller (unknown here)--also the default; usually want max
+     * compression (NOT the default); and remaining compression flags should
+     * be left alone */
+
+    png_set_compression_level(png_ptr, Z_BEST_COMPRESSION);
+/*
+    >> this is default for no filtering; Z_FILTERED is default otherwise:
+    png_set_compression_strategy(png_ptr, Z_DEFAULT_STRATEGY);
+    >> these are all defaults:
+    png_set_compression_mem_level(png_ptr, 8);
+    png_set_compression_window_bits(png_ptr, 15);
+    png_set_compression_method(png_ptr, 8);
+ */
+
+
+    /* set the image parameters appropriately */
+
+    if (mainprog_ptr->pnmtype == 5)
+        color_type = PNG_COLOR_TYPE_GRAY;
+    else if (mainprog_ptr->pnmtype == 6)
+        color_type = PNG_COLOR_TYPE_RGB;
+    else if (mainprog_ptr->pnmtype == 8)
+        color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+    else {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        return 11;
+    }
+
+    interlace_type = mainprog_ptr->interlaced? PNG_INTERLACE_ADAM7 :
+                                               PNG_INTERLACE_NONE;
+
+    png_set_IHDR(png_ptr, info_ptr, mainprog_ptr->width, mainprog_ptr->height,
+      mainprog_ptr->sample_depth, color_type, interlace_type,
+      PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
+
+    if (mainprog_ptr->gamma > 0.0)
+        png_set_gAMA(png_ptr, info_ptr, mainprog_ptr->gamma);
+
+    if (mainprog_ptr->have_bg) {   /* we know it's RGBA, not gray+alpha */
+        png_color_16  background;
+
+        background.red = mainprog_ptr->bg_red;
+        background.green = mainprog_ptr->bg_green;
+        background.blue = mainprog_ptr->bg_blue;
+        png_set_bKGD(png_ptr, info_ptr, &background);
+    }
+
+    if (mainprog_ptr->have_time) {
+        png_time  modtime;
+
+        png_convert_from_time_t(&modtime, mainprog_ptr->modtime);
+        png_set_tIME(png_ptr, info_ptr, &modtime);
+    }
+
+    if (mainprog_ptr->have_text) {
+        png_text  text[6];
+        int  num_text = 0;
+
+        if (mainprog_ptr->have_text & TEXT_TITLE) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Title";
+            text[num_text].text = mainprog_ptr->title;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_AUTHOR) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Author";
+            text[num_text].text = mainprog_ptr->author;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_DESC) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Description";
+            text[num_text].text = mainprog_ptr->desc;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_COPY) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Copyright";
+            text[num_text].text = mainprog_ptr->copyright;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_EMAIL) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "E-mail";
+            text[num_text].text = mainprog_ptr->email;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_URL) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "URL";
+            text[num_text].text = mainprog_ptr->url;
+            ++num_text;
+        }
+        png_set_text(png_ptr, info_ptr, text, num_text);
+    }
+
+
+    /* write all chunks up to (but not including) first IDAT */
+
+    png_write_info(png_ptr, info_ptr);
+
+
+    /* if we wanted to write any more text info *after* the image data, we
+     * would set up text struct(s) here and call png_set_text() again, with
+     * just the new data; png_set_tIME() could also go here, but it would
+     * have no effect since we already called it above (only one tIME chunk
+     * allowed) */
+
+
+    /* set up the transformations:  for now, just pack low-bit-depth pixels
+     * into bytes (one, two or four pixels per byte) */
+
+    png_set_packing(png_ptr);
+/*  png_set_shift(png_ptr, &sig_bit);  to scale low-bit-depth values */
+
+
+    /* make sure we save our pointers for use in writepng_encode_image() */
+
+    mainprog_ptr->png_ptr = png_ptr;
+    mainprog_ptr->info_ptr = info_ptr;
+
+
+    /* OK, that's all we need to do for now; return happy */
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 for success, 2 for libpng (longjmp) problem */
+
+int writepng_encode_image(mainprog_info *mainprog_ptr)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* and now we just write the whole image; libpng takes care of interlacing
+     * for us */
+
+    png_write_image(png_ptr, mainprog_ptr->row_pointers);
+
+
+    /* since that's it, we also close out the end of the PNG file now--if we
+     * had any text or time info to write after the IDATs, second argument
+     * would be info_ptr, but we optimize slightly by sending NULL pointer: */
+
+    png_write_end(png_ptr, NULL);
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 if succeeds, 2 if libpng problem */
+
+int writepng_encode_row(mainprog_info *mainprog_ptr)  /* NON-interlaced only! */
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* image_data points at our one row of image data */
+
+    png_write_row(png_ptr, mainprog_ptr->image_data);
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 if succeeds, 2 if libpng problem */
+
+int writepng_encode_finish(mainprog_info *mainprog_ptr)   /* NON-interlaced! */
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* close out PNG file; if we had any text or time info to write after
+     * the IDATs, second argument would be info_ptr: */
+
+    png_write_end(png_ptr, NULL);
+
+    return 0;
+}
+
+
+
+
+
+void writepng_cleanup(mainprog_info *mainprog_ptr)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+    if (png_ptr && info_ptr)
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+}
+
+
+
+
+
+static void writepng_error_handler(png_structp png_ptr, png_const_charp msg)
+{
+    mainprog_info  *mainprog_ptr;
+
+    /* This function, aside from the extra step of retrieving the "error
+     * pointer" (below) and the fact that it exists within the application
+     * rather than within libpng, is essentially identical to libpng's
+     * default error handler.  The second point is critical:  since both
+     * setjmp() and longjmp() are called from the same code, they are
+     * guaranteed to have compatible notions of how big a jmp_buf is,
+     * regardless of whether _BSD_SOURCE or anything else has (or has not)
+     * been defined. */
+
+    fprintf(stderr, "writepng libpng error: %s\n", msg);
+    fflush(stderr);
+
+    mainprog_ptr = png_get_error_ptr(png_ptr);
+    if (mainprog_ptr == NULL) {         /* we are completely hosed now */
+        fprintf(stderr,
+          "writepng severe error:  jmpbuf not recoverable; terminating.\n");
+        fflush(stderr);
+        exit(99);
+    }
+
+    longjmp(mainprog_ptr->jmpbuf, 1);
+}
diff --git a/gs/libpng/contrib/gregbook/writepng.h b/gs/libpng/contrib/gregbook/writepng.h
new file mode 100644
index 000000000..93c3da820
--- /dev/null
+++ b/gs/libpng/contrib/gregbook/writepng.h
@@ -0,0 +1,109 @@
+/*---------------------------------------------------------------------------
+
+   wpng - simple PNG-writing program                             writepng.h
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2000 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#ifndef TRUE
+#  define TRUE 1
+#  define FALSE 0
+#endif
+
+#ifndef MAX
+#  define MAX(a,b)  ((a) > (b)? (a) : (b))
+#  define MIN(a,b)  ((a) < (b)? (a) : (b))
+#endif
+
+#ifdef DEBUG
+#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}
+#else
+#  define Trace(x)  ;
+#endif
+
+#define TEXT_TITLE    0x01
+#define TEXT_AUTHOR   0x02
+#define TEXT_DESC     0x04
+#define TEXT_COPY     0x08
+#define TEXT_EMAIL    0x10
+#define TEXT_URL      0x20
+
+#define TEXT_TITLE_OFFSET        0
+#define TEXT_AUTHOR_OFFSET      72
+#define TEXT_COPY_OFFSET     (2*72)
+#define TEXT_EMAIL_OFFSET    (3*72)
+#define TEXT_URL_OFFSET      (4*72)
+#define TEXT_DESC_OFFSET     (5*72)
+
+typedef unsigned char   uch;
+typedef unsigned short  ush;
+typedef unsigned long   ulg;
+
+typedef struct _mainprog_info {
+    double gamma;
+    long width;
+    long height;
+    time_t modtime;
+    FILE *infile;
+    FILE *outfile;
+    void *png_ptr;
+    void *info_ptr;
+    uch *image_data;
+    uch **row_pointers;
+    char *title;
+    char *author;
+    char *desc;
+    char *copyright;
+    char *email;
+    char *url;
+    int filter;    /* command-line-filter flag, not PNG row filter! */
+    int pnmtype;
+    int sample_depth;
+    int interlaced;
+    int have_bg;
+    int have_time;
+    int have_text;
+    jmp_buf jmpbuf;
+    uch bg_red;
+    uch bg_green;
+    uch bg_blue;
+} mainprog_info;
+
+
+/* prototypes for public functions in writepng.c */
+
+void writepng_version_info(void);
+
+int writepng_init(mainprog_info *mainprog_ptr);
+
+int writepng_encode_image(mainprog_info *mainprog_ptr);
+
+int writepng_encode_row(mainprog_info *mainprog_ptr);
+
+int writepng_encode_finish(mainprog_info *mainprog_ptr);
+
+void writepng_cleanup(mainprog_info *mainprog_ptr);
diff --git a/gs/libpng/contrib/pngminus/README b/gs/libpng/contrib/pngminus/README
new file mode 100644
index 000000000..8683a596a
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/README
@@ -0,0 +1,153 @@
+PngMinus
+--------
+(copyright Willem van Schaik, 1999)
+
+
+License
+-------
+
+Permission to use, copy, modify, and distribute this software and
+its documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and
+that both that copyright notice and this permission notice appear in
+supporting documentation. This software is provided "as is" without
+express or implied warranty.
+
+
+Some history
+------------
+Soon after the creation of PNG in 1995, the need was felt for a set of
+pnmtopng / pngtopnm utilities. Independantly Alexander Lehmann and I
+(Willem van Schaik) started such a project. Luckily we discovered this
+and merged the two together into pnmtopng.tar.gz, which is available
+from a/o ftp://swrinde.nde.swri.edu/pub/png/.
+
+These two utilities have many, many options and make use of most of the
+features of PNG, like gamma, alpha, sbit, text-chunks, etc. This makes
+the utilities quite complex and by now not anymore very maintainable.
+When we wrote these programs, libpng was still in an early stage.
+Therefore, lots of the functionality that we put in our software can now
+be done using transform-functions in libpng.
+
+Finally, to compile these programs, you need to have installed and
+compiled three libraries: libpng, zlib and netpbm. Especially the latter
+makes the whole setup a bit bulky. But that's unavoidable given the many
+features of pnmtopng.
+
+
+What now
+--------
+At this moment libpng is in a very stable state and can do much of the
+work done in pnmtopng. Also, pnmtopng needs to be upgraded to the new
+interface of libpng. Hence, it is time for a rewrite from the ground up
+of pnmtopng and pngtopnm. This will happen in the near future (stay
+tuned). The new package will get a different name to distinguish it from
+the old one: PngPlus.
+
+To experiment a bit with the new interface of libpng, I started off with
+a small prototype that contains only the basic functionality. It doesn't
+have any of the options to read or write special chunks and it will do
+no gamma correction. But this makes it also a simple program that is
+quite easy to understand and can serve well as a template for other
+software developments. (By now there are of course a couple of programs,
+like Greg Roelofs' rpng/wpng, that can be used just as good.)
+
+
+Can and can not
+---------------
+As this is the small brother of the future PngPlus, I called this fellow
+PngMinus. Because I started this development in good-old Turbo-C, I
+avoided the use the netpbm library, which requires DOS extenders. Again,
+another reason to call it PngMinus (minus netpbm :-). So, part of the
+program are some elementary routines to read / write pgm- and ppm-files.
+It does not read b&w pbm-files.
+
+The downside of this approach is that you can not use them on images
+that require blocks of memory bigger than 64k (the DOS version). For
+larger images you will get an out-of-memory error.
+
+As said before, PngMinus doesn't correct for gamma. When reading
+png-files you can do this just as well by piping the output of png2pnm
+to pnmgamma, one of the standard PbmPlus tools. This same scenario will
+most probably also be followed in the full-blown future PngPlus, with
+the addition of course of the possibility to create gamma-chunks when
+writing png-files.
+
+On the other hand it supports alpha-channels. When reading a png-image
+you can write the alpha-channel into a pgm-file. And when creating an
+RGB+A png-image, you just combine a ppm-file with a corresponding
+pgm-file containing the alpha-channel. When reading, transparency chunks
+are converted into an alpha-channel and from there on treated the same
+way.
+
+Finally you can opt for writing ascii or binary pgm- and ppm-files. When
+the bit-depth is 16, the format will always be ascii.
+
+
+Using it
+--------
+To distinguish them from pnmtopng and PngPlus, the utilities are named
+png2pnm and pnm2png (2 instead of to). The input- and output-files can
+be given as parameters or through redirection. Therefore the programs
+can be part of a pipe.
+
+To list the options type "png2pnm -h" or "pnm2png -h".
+
+
+Just like Scandinavian furniture
+--------------------------------
+You have to put it together yourself. I did test the software under
+MS-DOS with Turbo-C 3.0 and under RedHat Linux 4.2 with gcc. In both
+cases I used libpng-1.0.4 and zlib-1.1.3. Later versions should be OK,
+however some older libpng versions have a bug in pngmem.c when using
+Turbo-C 3.0 (see below).
+
+You can build it using one of the two makefiles (make -f makefile.###)
+or use the batch/script files pngminus.bat / pngminus.sh. This assumes
+that you have built the libraries in ../libpng and ../zlib. Using Linux,
+make sure that you have built libpng with makefile.std and not
+makefile.linux (also called .lnx in earlier versions of libpng). The
+latter creates a .so shared-library, while the PngMinus makefile assumes
+a normal .a static library.
+
+If you create a ../pngsuite directory and then store the basn####.png
+files from PngSuite (http://www.schaik.com/pngsuite/) in there, you can
+test in one go the proper functioning of PngMinus, see png2pnm.bat and
+pnm2png.bat (or the .sh versions).
+
+
+Warranty
+-------
+Please, remember that this was just a small experiment to learn a few
+things. It will have many unforeseen features <vbg>. Who said bugs? Use
+it when you are in need for something simple or when you want to start
+developing your own stuff.
+
+
+The Turbo bug
+-------------
+** pngmem.old
+          hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
+          hptr += 16L;
+** pngmem.c
+          hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
+          hptr = hptr + 16L;
+**
+
+** pngmem.old
+          png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
+          hptr += (png_uint_32)65536L;
+** pngmem.c
+          png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
+          hptr = hptr + 65536L;
+**
+
+
+The end
+-------
+Willem van Schaik
+mailto:willem@schaik.com
+http://www.schaik.com/png/
+-------
+Oct 1999
+
diff --git a/gs/libpng/contrib/pngminus/makefile.std b/gs/libpng/contrib/pngminus/makefile.std
new file mode 100644
index 000000000..2fb061bbe
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/makefile.std
@@ -0,0 +1,65 @@
+# Makefile for PngMinus (png2pnm and pnm2png)
+# Linux / Unix
+
+#CC=cc
+CC=gcc
+LD=$(CC)
+
+RM=rm -f
+
+#PNGPATH = /usr/local
+#PNGINC = -I$(PNGPATH)/include/libpng12
+#PNGLIB = -L$(PNGPATH)/lib -lpng12
+#PNGLIBS = $(PNGPATH)/lib/libpng12.a
+PNGINC = -I../..
+PNGLIB = -L../.. -lpng
+PNGLIBS = ../../libpng.a
+
+#ZPATH = /usr/local
+#ZINC = -I$(ZPATH)/include
+#ZLIB = -L$(ZPATH)/lib -lz
+#ZLIBS = $(ZPATH)/lib/libz.a
+ZINC = -I../../../zlib
+ZLIB = -L../../../zlib -lz
+ZLIBS = ../../../zlib/libz.a
+
+CFLAGS=-O3 $(PNGINC) $(ZINC)
+LDFLAGS=$(PNGLIB) $(ZLIB)
+LDFLAGSS=$(PNGLIBS) $(ZLIBS)
+C=.c
+O=.o
+L=.a
+E=
+
+# dependencies
+
+#all: png2pnm$(E) pnm2png$(E)
+all: png2pnm$(E) pnm2png$(E) png2pnm-static$(E) pnm2png-static$(E)
+
+png2pnm$(O): png2pnm$(C)
+	$(CC) -c $(CFLAGS) png2pnm$(C)
+
+png2pnm$(E): png2pnm$(O)
+	$(LD) -o png2pnm$(E) png2pnm$(O) $(LDFLAGS) -lm
+
+png2pnm-static$(E): png2pnm$(O)
+	$(LD) -o png2pnm-static$(E) png2pnm$(O) $(LDFLAGSS) -lm
+
+pnm2png$(O): pnm2png$(C)
+	$(CC) -c $(CFLAGS) pnm2png$(C)
+
+pnm2png$(E): pnm2png$(O)
+	$(LD) -o pnm2png$(E) pnm2png$(O) $(LDFLAGS) -lm
+
+pnm2png-static$(E): pnm2png$(O)
+	$(LD) -o pnm2png-static$(E) pnm2png$(O) $(LDFLAGSS) -lm
+
+clean:
+	$(RM) png2pnm$(O)
+	$(RM) pnm2png$(O)
+	$(RM) png2pnm$(E)
+	$(RM) pnm2png$(E)
+	$(RM) png2pnm-static$(E)
+	$(RM) pnm2png-static$(E)
+
+# End of makefile for png2pnm / pnm2png
diff --git a/gs/libpng/contrib/pngminus/makefile.tc3 b/gs/libpng/contrib/pngminus/makefile.tc3
new file mode 100644
index 000000000..404f18d5b
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/makefile.tc3
@@ -0,0 +1,38 @@
+# Makefile for PngMinus (png2pnm and pnm2png)
+# TurboC++ 3.0
+
+CC=tcc -Ic:\tc3\inc
+LD=tcc -Lc:\tc3\lib
+LB=tlib
+RM=del
+CP=copy
+MODEL=l
+CCFLAGS=-O -m$(MODEL) -I..\libpng -I..\zlib
+LDFLAGS=-m$(MODEL) -L..\libpng -L..\zlib
+C=.c
+O=.obj
+L=.lib
+E=.exe
+
+# dependencies
+
+all: png2pnm$(E) pnm2png$(E)
+
+png2pnm$(O): png2pnm$(C)
+        $(CC) -c $(CCFLAGS) png2pnm$(C)
+
+png2pnm$(E): png2pnm$(O)
+        $(LD) $(LDFLAGS) png2pnm$(O) libpng$(L) zlib$(L)
+
+pnm2png$(O): pnm2png$(C)
+        $(CC) -c $(CCFLAGS) pnm2png$(C)
+
+pnm2png$(E): pnm2png$(O)
+        $(LD) $(LDFLAGS) pnm2png$(O) libpng$(L) zlib$(L)
+
+clean:
+        $(RM) *$(O)
+        $(RM) *$(E)
+
+# End of makefile for png2pnm / pnm2png
+
diff --git a/gs/libpng/contrib/pngminus/makevms.com b/gs/libpng/contrib/pngminus/makevms.com
new file mode 100644
index 000000000..00561bcd0
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/makevms.com
@@ -0,0 +1,92 @@
+$!------------------------------------------------------------------------------
+$! make Contrib programs of libpng under OpenVMS
+$!
+$!
+$! Look for the compiler used
+$!
+$ zlibsrc = "[---.zlib]"
+$ ccopt="/include=(''zlibsrc',[--])"
+$ if f$getsyi("HW_MODEL").ge.1024
+$ then
+$  ccopt = "/prefix=all"+ccopt
+$  comp  = "__decc__=1"
+$  if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$ else
+$  if f$search("SYS$SYSTEM:DECC$COMPILER.EXE").eqs.""
+$   then
+$    if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$    if f$search("SYS$SYSTEM:VAXC.EXE").eqs.""
+$     then
+$      comp  = "__gcc__=1"
+$      CC :== GCC
+$     else
+$      comp = "__vaxc__=1"
+$     endif
+$   else
+$    if f$trnlnm("SYS").eqs."" then define sys decc$library_include:
+$    ccopt = "/decc/prefix=all"+ccopt
+$    comp  = "__decc__=1"
+$  endif
+$ endif
+$ open/write lopt lib.opt
+$ write lopt "[--]libpng.olb/lib"
+$ write lopt "''zlibsrc'libz.olb/lib"
+$ close lopt
+$ open/write xopt x11.opt
+$ write xopt "sys$library:decw$xlibshr.exe/share"
+$ close xopt
+$ write sys$output "Compiling PNG contrib programs ..."
+$   write sys$output "Building pnm2png..."
+$   CALL MAKE pnm2png.OBJ "cc ''CCOPT' pnm2png" -
+	pnm2png.c
+$   call make pnm2png.exe -
+	"LINK pnm2png,lib.opt/opt" -
+	pnm2png.obj
+$   write sys$output "Building png2pnm..."
+$   CALL MAKE png2pnm.OBJ "cc ''CCOPT' png2pnm" -
+	png2pnm.c
+$   call make png2pnm.exe -
+	"LINK png2pnm,lib.opt/opt" -
+	png2pnm.obj
+$ exit
+$!
+$!
+$MAKE: SUBROUTINE   !SUBROUTINE TO CHECK DEPENDENCIES
+$ V = 'F$Verify(0)
+$! P1 = What we are trying to make
+$! P2 = Command to make it
+$! P3 - P8  What it depends on
+$
+$ If F$Search(P1) .Eqs. "" Then Goto Makeit
+$ Time = F$CvTime(F$File(P1,"RDT"))
+$arg=3
+$Loop:
+$       Argument = P'arg
+$       If Argument .Eqs. "" Then Goto Exit
+$       El=0
+$Loop2:
+$       File = F$Element(El," ",Argument)
+$       If File .Eqs. " " Then Goto Endl
+$       AFile = ""
+$Loop3:
+$       OFile = AFile
+$       AFile = F$Search(File)
+$       If AFile .Eqs. "" .Or. AFile .Eqs. OFile Then Goto NextEl
+$       If F$CvTime(F$File(AFile,"RDT")) .Ges. Time Then Goto Makeit
+$       Goto Loop3
+$NextEL:
+$       El = El + 1
+$       Goto Loop2
+$EndL:
+$ arg=arg+1
+$ If arg .Le. 8 Then Goto Loop
+$ Goto Exit
+$
+$Makeit:
+$ VV=F$VERIFY(0)
+$ write sys$output P2
+$ 'P2
+$ VV='F$Verify(VV)
+$Exit:
+$ If V Then Set Verify
+$ENDSUBROUTINE
diff --git a/gs/libpng/contrib/pngminus/png2pnm.bat b/gs/libpng/contrib/pngminus/png2pnm.bat
new file mode 100644
index 000000000..449cf3675
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/png2pnm.bat
@@ -0,0 +1,41 @@
+REM -- grayscale
+png2pnm.exe -noraw ..\pngsuite\basn0g01.png basn0g01.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g02.png basn0g02.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g04.png basn0g04.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g08.png basn0g08.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g16.png basn0g16.pgm
+REM -- full-color
+png2pnm.exe -noraw ..\pngsuite\basn2c08.png basn2c08.ppm
+png2pnm.exe -noraw ..\pngsuite\basn2c16.png basn2c16.ppm
+REM -- palletted
+png2pnm.exe -noraw ..\pngsuite\basn3p01.png basn3p01.ppm
+png2pnm.exe -noraw ..\pngsuite\basn3p02.png basn3p02.ppm
+png2pnm.exe -noraw ..\pngsuite\basn3p04.png basn3p04.ppm
+png2pnm.exe -noraw ..\pngsuite\basn3p08.png basn3p08.ppm
+REM -- gray with alpha-channel
+png2pnm.exe -noraw ..\pngsuite\basn4a08.png basn4a08.pgm
+png2pnm.exe -noraw ..\pngsuite\basn4a16.png basn4a16.pgm
+REM -- color with alpha-channel
+png2pnm.exe -noraw -alpha basn6a08.pgm ..\pngsuite\basn6a08.png basn6a08.ppm
+png2pnm.exe -noraw -alpha basn6a16.pgm ..\pngsuite\basn6a16.png basn6a16.ppm
+REM -- grayscale
+png2pnm.exe -raw ..\pngsuite\basn0g01.png rawn0g01.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g02.png rawn0g02.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g04.png rawn0g04.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g08.png rawn0g08.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g16.png rawn0g16.pgm
+REM -- full-color
+png2pnm.exe -raw ..\pngsuite\basn2c08.png rawn2c08.ppm
+png2pnm.exe -raw ..\pngsuite\basn2c16.png rawn2c16.ppm
+REM -- palletted
+png2pnm.exe -raw ..\pngsuite\basn3p01.png rawn3p01.ppm
+png2pnm.exe -raw ..\pngsuite\basn3p02.png rawn3p02.ppm
+png2pnm.exe -raw ..\pngsuite\basn3p04.png rawn3p04.ppm
+png2pnm.exe -raw ..\pngsuite\basn3p08.png rawn3p08.ppm
+REM -- gray with alpha-channel
+png2pnm.exe -raw ..\pngsuite\basn4a08.png rawn4a08.pgm
+png2pnm.exe -raw ..\pngsuite\basn4a16.png rawn4a16.pgm
+REM -- color with alpha-channel
+png2pnm.exe -noraw -alpha rawn6a08.pgm ..\pngsuite\basn6a08.png rawn6a08.ppm
+png2pnm.exe -noraw -alpha rawn6a16.pgm ..\pngsuite\basn6a16.png rawn6a16.ppm
+
diff --git a/gs/libpng/contrib/pngminus/png2pnm.c b/gs/libpng/contrib/pngminus/png2pnm.c
new file mode 100644
index 000000000..010870a76
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/png2pnm.c
@@ -0,0 +1,430 @@
+/*
+ *  png2pnm.c --- conversion from PNG-file to PGM/PPM-file
+ *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
+ *
+ *  version 1.0 - 1999.10.15 - First version.
+ *
+ *  Permission to use, copy, modify, and distribute this software and
+ *  its documentation for any purpose and without fee is hereby granted,
+ *  provided that the above copyright notice appear in all copies and
+ *  that both that copyright notice and this permission notice appear in
+ *  supporting documentation. This software is provided "as is" without
+ *  express or implied warranty.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef __TURBOC__
+#include <mem.h>
+#include <fcntl.h>
+#endif
+
+#ifndef BOOL
+#define BOOL unsigned char
+#endif
+#ifndef TRUE
+#define TRUE (BOOL) 1
+#endif
+#ifndef FALSE
+#define FALSE (BOOL) 0
+#endif
+
+#ifdef __TURBOC__
+#define STDIN  0
+#define STDOUT 1
+#define STDERR 2
+#endif
+
+/* to make png2pnm verbose so we can find problems (needs to be before png.h) */
+#ifndef PNG_DEBUG
+#define PNG_DEBUG 0
+#endif
+
+#include "png.h"
+
+/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
+#ifndef png_jmpbuf
+#  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
+#endif
+
+/* function prototypes */
+
+int  main (int argc, char *argv[]);
+void usage ();
+BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw, BOOL alpha);
+
+/*
+ *  main
+ */
+
+int main(int argc, char *argv[])
+{
+  FILE *fp_rd = stdin;
+  FILE *fp_wr = stdout;
+  FILE *fp_al = NULL;
+  BOOL raw = TRUE;
+  BOOL alpha = FALSE;
+  int argi;
+
+  for (argi = 1; argi < argc; argi++)
+  {
+    if (argv[argi][0] == '-')
+    {
+      switch (argv[argi][1])
+      {
+        case 'n':
+          raw = FALSE;
+          break;
+        case 'r':
+          raw = TRUE;
+          break;
+        case 'a':
+          alpha = TRUE;
+          argi++;
+          if ((fp_al = fopen (argv[argi], "wb")) == NULL)
+          {
+            fprintf (stderr, "PNM2PNG\n");
+            fprintf (stderr, "Error:  can not create alpha-channel file %s\n", argv[argi]);
+            exit (1);
+          }
+          break;
+        case 'h':
+        case '?':
+          usage();
+          exit(0);
+          break;
+        default:
+          fprintf (stderr, "PNG2PNM\n");
+          fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);
+          usage();
+          exit(1);
+          break;
+      } /* end switch */
+    }
+    else if (fp_rd == stdin)
+    {
+      if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
+      {
+             fprintf (stderr, "PNG2PNM\n");
+            fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);
+            exit (1);
+      }
+    }
+    else if (fp_wr == stdout)
+    {
+      if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
+      {
+        fprintf (stderr, "PNG2PNM\n");
+        fprintf (stderr, "Error:  can not create file %s\n", argv[argi]);
+        exit (1);
+      }
+    }
+    else
+    {
+      fprintf (stderr, "PNG2PNM\n");
+      fprintf (stderr, "Error:  too many parameters\n");
+      usage();
+      exit(1);
+    }
+  } /* end for */
+
+#ifdef __TURBOC__
+  /* set stdin/stdout if required to binary */
+  if (fp_rd == stdin)
+  {
+    setmode (STDIN, O_BINARY);
+  }
+  if ((raw) && (fp_wr == stdout))
+  {
+    setmode (STDOUT, O_BINARY);
+  }
+#endif
+
+  /* call the conversion program itself */
+  if (png2pnm (fp_rd, fp_wr, fp_al, raw, alpha) == FALSE)
+  {
+    fprintf (stderr, "PNG2PNM\n");
+    fprintf (stderr, "Error:  unsuccessful convertion of PNG-image\n");
+    exit(1);
+  }
+
+  /* close input file */
+  fclose (fp_rd);
+  /* close output file */
+  fclose (fp_wr);
+  /* close alpha file */
+  if (alpha)
+    fclose (fp_al);
+
+  return 0;
+}
+
+/*
+ *  usage
+ */
+
+void usage()
+{
+  fprintf (stderr, "PNG2PNM\n");
+  fprintf (stderr, "   by Willem van Schaik, 1999\n");
+#ifdef __TURBOC__
+  fprintf (stderr, "   for Turbo-C and Borland-C compilers\n");
+#else
+  fprintf (stderr, "   for Linux (and Unix) compilers\n");
+#endif
+  fprintf (stderr, "Usage:  png2pnm [options] <file>.png [<file>.pnm]\n");
+  fprintf (stderr, "   or:  ... | png2pnm [options]\n");
+  fprintf (stderr, "Options:\n");
+  fprintf (stderr, "   -r[aw]   write pnm-file in binary format (P4/P5/P6) (default)\n");
+  fprintf (stderr, "   -n[oraw] write pnm-file in ascii format (P1/P2/P3)\n");
+  fprintf (stderr, "   -a[lpha] <file>.pgm write PNG alpha channel as pgm-file\n");
+  fprintf (stderr, "   -h | -?  print this help-information\n");
+}
+
+/*
+ *  png2pnm
+ */
+
+BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw, BOOL alpha)
+{
+  png_struct    *png_ptr = NULL;
+  png_info	*info_ptr = NULL;
+  png_byte      buf[8];
+  png_byte      *png_pixels = NULL;
+  png_byte      **row_pointers = NULL;
+  png_byte      *pix_ptr = NULL;
+  png_uint_32   row_bytes;
+
+  png_uint_32   width;
+  png_uint_32   height;
+  int           bit_depth;
+  int           channels;
+  int           color_type;
+  int           alpha_present;
+  int           row, col;
+  int           ret;
+  int           i;
+  long          dep_16;
+
+  /* read and check signature in PNG file */
+  ret = fread (buf, 1, 8, png_file);
+  if (ret != 8)
+    return FALSE;
+
+  ret = png_check_sig (buf, 8);
+  if (!ret)
+    return FALSE;
+
+  /* create png and info structures */
+
+  png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING,
+    NULL, NULL, NULL);
+  if (!png_ptr)
+    return FALSE;   /* out of memory */
+
+  info_ptr = png_create_info_struct (png_ptr);
+  if (!info_ptr)
+  {
+    png_destroy_read_struct (&png_ptr, NULL, NULL);
+    return FALSE;   /* out of memory */
+  }
+
+  if (setjmp (png_jmpbuf(png_ptr)))
+  {
+    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+    return FALSE;
+  }
+
+  /* set up the input control for C streams */
+  png_init_io (png_ptr, png_file);
+  png_set_sig_bytes (png_ptr, 8);  /* we already read the 8 signature bytes */
+
+  /* read the file information */
+  png_read_info (png_ptr, info_ptr);
+
+  /* get size and bit-depth of the PNG-image */
+  png_get_IHDR (png_ptr, info_ptr,
+    &width, &height, &bit_depth, &color_type,
+    NULL, NULL, NULL);
+
+  /* set-up the transformations */
+
+  /* transform paletted images into full-color rgb */
+  if (color_type == PNG_COLOR_TYPE_PALETTE)
+    png_set_expand (png_ptr);
+  /* expand images to bit-depth 8 (only applicable for grayscale images) */
+  if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+    png_set_expand (png_ptr);
+  /* transform transparency maps into full alpha-channel */
+  if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS))
+    png_set_expand (png_ptr);
+
+#ifdef NJET
+  /* downgrade 16-bit images to 8 bit */
+  if (bit_depth == 16)
+    png_set_strip_16 (png_ptr);
+  /* transform grayscale images into full-color */
+  if (color_type == PNG_COLOR_TYPE_GRAY ||
+    color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+    png_set_gray_to_rgb (png_ptr);
+  /* only if file has a file gamma, we do a correction */
+  if (png_get_gAMA (png_ptr, info_ptr, &file_gamma))
+    png_set_gamma (png_ptr, (double) 2.2, file_gamma);
+#endif
+
+  /* all transformations have been registered; now update info_ptr data,
+   * get rowbytes and channels, and allocate image memory */
+
+  png_read_update_info (png_ptr, info_ptr);
+
+  /* get the new color-type and bit-depth (after expansion/stripping) */
+  png_get_IHDR (png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+    NULL, NULL, NULL);
+
+  /* check for 16-bit files */
+  if (bit_depth == 16)
+  {
+    raw = FALSE;
+#ifdef __TURBOC__
+    pnm_file->flags &= ~((unsigned) _F_BIN);
+#endif
+  }
+
+  /* calculate new number of channels and store alpha-presence */
+  if (color_type == PNG_COLOR_TYPE_GRAY)
+    channels = 1;
+  else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+    channels = 2;
+  else if (color_type == PNG_COLOR_TYPE_RGB)
+    channels = 3;
+  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+    channels = 4;
+  else
+    channels = 0; /* should never happen */
+  alpha_present = (channels - 1) % 2;
+
+  /* check if alpha is expected to be present in file */
+  if (alpha && !alpha_present)
+  {
+    fprintf (stderr, "PNG2PNM\n");
+    fprintf (stderr, "Error:  PNG-file doesn't contain alpha channel\n");
+    exit (1);
+  }
+
+  /* row_bytes is the width x number of channels x (bit-depth / 8) */
+  row_bytes = png_get_rowbytes (png_ptr, info_ptr);
+
+  if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL) {
+    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+    return FALSE;
+  }
+
+  if ((row_pointers = (png_byte **) malloc (height * sizeof (png_bytep))) == NULL)
+  {
+    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+    free (png_pixels);
+    png_pixels = NULL;
+    return FALSE;
+  }
+
+  /* set the individual row_pointers to point at the correct offsets */
+  for (i = 0; i < (height); i++)
+    row_pointers[i] = png_pixels + i * row_bytes;
+
+  /* now we can go ahead and just read the whole image */
+  png_read_image (png_ptr, row_pointers);
+
+  /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
+  png_read_end (png_ptr, info_ptr);
+
+  /* clean up after the read, and free any memory allocated - REQUIRED */
+  png_destroy_read_struct (&png_ptr, &info_ptr, (png_infopp) NULL);
+
+  /* write header of PNM file */
+
+  if ((color_type == PNG_COLOR_TYPE_GRAY) ||
+      (color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
+  {
+    fprintf (pnm_file, "%s\n", (raw) ? "P5" : "P2");
+    fprintf (pnm_file, "%d %d\n", (int) width, (int) height);
+    fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
+  }
+  else if ((color_type == PNG_COLOR_TYPE_RGB) ||
+           (color_type == PNG_COLOR_TYPE_RGB_ALPHA))
+  {
+    fprintf (pnm_file, "%s\n", (raw) ? "P6" : "P3");
+    fprintf (pnm_file, "%d %d\n", (int) width, (int) height);
+    fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
+  }
+
+  /* write header of PGM file with alpha channel */
+
+  if ((alpha) &&
+      ((color_type == PNG_COLOR_TYPE_GRAY_ALPHA) ||
+       (color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
+  {
+    fprintf (alpha_file, "%s\n", (raw) ? "P5" : "P2");
+    fprintf (alpha_file, "%d %d\n", (int) width, (int) height);
+    fprintf (alpha_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
+  }
+
+  /* write data to PNM file */
+  pix_ptr = png_pixels;
+
+  for (row = 0; row < height; row++)
+  {
+    for (col = 0; col < width; col++)
+    {
+      for (i = 0; i < (channels - alpha_present); i++)
+      {
+        if (raw)
+          fputc ((int) *pix_ptr++ , pnm_file);
+        else
+          if (bit_depth == 16){
+	    dep_16 = (long) *pix_ptr++;
+            fprintf (pnm_file, "%ld ", (dep_16 << 8) + ((long) *pix_ptr++));
+          }
+          else
+            fprintf (pnm_file, "%ld ", (long) *pix_ptr++);
+      }
+      if (alpha_present)
+      {
+        if (!alpha)
+        {
+          pix_ptr++; /* alpha */
+          if (bit_depth == 16)
+            pix_ptr++;
+        }
+        else /* output alpha-channel as pgm file */
+        {
+          if (raw)
+            fputc ((int) *pix_ptr++ , alpha_file);
+          else
+            if (bit_depth == 16){
+	      dep_16 = (long) *pix_ptr++;
+              fprintf (alpha_file, "%ld ", (dep_16 << 8) + (long) *pix_ptr++);
+	    }  
+            else
+              fprintf (alpha_file, "%ld ", (long) *pix_ptr++);
+        }
+      } /* if alpha_present */
+
+      if (!raw)
+        if (col % 4 == 3)
+          fprintf (pnm_file, "\n");
+    } /* end for col */
+
+    if (!raw)
+      if (col % 4 != 0)
+        fprintf (pnm_file, "\n");
+  } /* end for row */
+
+  if (row_pointers != (unsigned char**) NULL)
+    free (row_pointers);
+  if (png_pixels != (unsigned char*) NULL)
+    free (png_pixels);
+
+  return TRUE;
+
+} /* end of source */
+
diff --git a/gs/libpng/contrib/pngminus/png2pnm.sh b/gs/libpng/contrib/pngminus/png2pnm.sh
new file mode 100644
index 000000000..854313bad
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/png2pnm.sh
@@ -0,0 +1,41 @@
+# -- grayscale
+./png2pnm -noraw ../pngsuite/basn0g01.png basn0g01.pgm
+./png2pnm -noraw ../pngsuite/basn0g02.png basn0g02.pgm
+./png2pnm -noraw ../pngsuite/basn0g04.png basn0g04.pgm
+./png2pnm -noraw ../pngsuite/basn0g08.png basn0g08.pgm
+./png2pnm -noraw ../pngsuite/basn0g16.png basn0g16.pgm
+# -- full-color
+./png2pnm -noraw ../pngsuite/basn2c08.png basn2c08.ppm
+./png2pnm -noraw ../pngsuite/basn2c16.png basn2c16.ppm
+# -- palletted
+./png2pnm -noraw ../pngsuite/basn3p01.png basn3p01.ppm
+./png2pnm -noraw ../pngsuite/basn3p02.png basn3p02.ppm
+./png2pnm -noraw ../pngsuite/basn3p04.png basn3p04.ppm
+./png2pnm -noraw ../pngsuite/basn3p08.png basn3p08.ppm
+# -- gray with alpha-channel
+./png2pnm -noraw ../pngsuite/basn4a08.png basn4a08.pgm
+./png2pnm -noraw ../pngsuite/basn4a16.png basn4a16.pgm
+# -- color with alpha-channel
+./png2pnm -noraw -alpha basn6a08.pgm ../pngsuite/basn6a08.png basn6a08.ppm
+./png2pnm -noraw -alpha basn6a16.pgm ../pngsuite/basn6a16.png basn6a16.ppm
+# -- grayscale
+./png2pnm -raw ../pngsuite/basn0g01.png rawn0g01.pgm
+./png2pnm -raw ../pngsuite/basn0g02.png rawn0g02.pgm
+./png2pnm -raw ../pngsuite/basn0g04.png rawn0g04.pgm
+./png2pnm -raw ../pngsuite/basn0g08.png rawn0g08.pgm
+./png2pnm -raw ../pngsuite/basn0g16.png rawn0g16.pgm
+# -- full-color
+./png2pnm -raw ../pngsuite/basn2c08.png rawn2c08.ppm
+./png2pnm -raw ../pngsuite/basn2c16.png rawn2c16.ppm
+# -- palletted
+./png2pnm -raw ../pngsuite/basn3p01.png rawn3p01.ppm
+./png2pnm -raw ../pngsuite/basn3p02.png rawn3p02.ppm
+./png2pnm -raw ../pngsuite/basn3p04.png rawn3p04.ppm
+./png2pnm -raw ../pngsuite/basn3p08.png rawn3p08.ppm
+# -- gray with alpha-channel
+./png2pnm -raw ../pngsuite/basn4a08.png rawn4a08.pgm
+./png2pnm -raw ../pngsuite/basn4a16.png rawn4a16.pgm
+# -- color with alpha-channel
+./png2pnm -noraw -alpha rawn6a08.pgm ../pngsuite/basn6a08.png rawn6a08.ppm
+./png2pnm -noraw -alpha rawn6a16.pgm ../pngsuite/basn6a16.png rawn6a16.ppm
+
diff --git a/gs/libpng/contrib/pngminus/pngminus.bat b/gs/libpng/contrib/pngminus/pngminus.bat
new file mode 100644
index 000000000..911bb8dff
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/pngminus.bat
@@ -0,0 +1,4 @@
+make -f makefile.tc3
+call png2pnm.bat
+call pnm2png.bat
+
diff --git a/gs/libpng/contrib/pngminus/pngminus.sh b/gs/libpng/contrib/pngminus/pngminus.sh
new file mode 100644
index 000000000..6b2d8c5e4
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/pngminus.sh
@@ -0,0 +1,4 @@
+make -f makefile.std
+sh png2pnm.sh
+sh pnm2png.sh
+
diff --git a/gs/libpng/contrib/pngminus/pnm2png.bat b/gs/libpng/contrib/pngminus/pnm2png.bat
new file mode 100644
index 000000000..f756cb84d
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/pnm2png.bat
@@ -0,0 +1,41 @@
+REM -- grayscale
+pnm2png.exe basn0g01.pgm basn0g01.png
+pnm2png.exe basn0g02.pgm basn0g02.png
+pnm2png.exe basn0g04.pgm basn0g04.png
+pnm2png.exe basn0g08.pgm basn0g08.png
+pnm2png.exe basn0g16.pgm basn0g16.png
+REM -- full-color
+pnm2png.exe basn2c08.ppm basn2c08.png
+pnm2png.exe basn2c16.ppm basn2c16.png
+REM -- palletted
+pnm2png.exe basn3p01.ppm basn3p01.png
+pnm2png.exe basn3p02.ppm basn3p02.png
+pnm2png.exe basn3p04.ppm basn3p04.png
+pnm2png.exe basn3p08.ppm basn3p08.png
+REM -- gray with alpha-channel
+pnm2png.exe -alpha basn6a08.pgm basn4a08.pgm basn4a08.png
+pnm2png.exe -alpha basn6a16.pgm basn4a16.pgm basn4a16.png
+REM -- color with alpha-channel
+pnm2png.exe -alpha basn6a08.pgm basn6a08.ppm basn6a08.png
+pnm2png.exe -alpha basn6a16.pgm basn6a16.ppm basn6a16.png
+REM -- grayscale
+pnm2png.exe rawn0g01.pgm rawn0g01.png
+pnm2png.exe rawn0g02.pgm rawn0g02.png
+pnm2png.exe rawn0g04.pgm rawn0g04.png
+pnm2png.exe rawn0g08.pgm rawn0g08.png
+pnm2png.exe rawn0g16.pgm rawn0g16.png
+REM -- full-color
+pnm2png.exe rawn2c08.ppm rawn2c08.png
+pnm2png.exe rawn2c16.ppm rawn2c16.png
+REM -- palletted
+pnm2png.exe rawn3p01.ppm rawn3p01.png
+pnm2png.exe rawn3p02.ppm rawn3p02.png
+pnm2png.exe rawn3p04.ppm rawn3p04.png
+pnm2png.exe rawn3p08.ppm rawn3p08.png
+REM -- gray with alpha-channel
+pnm2png.exe -alpha rawn6a08.pgm rawn4a08.pgm rawn4a08.png
+pnm2png.exe -alpha rawn6a16.pgm rawn4a16.pgm rawn4a16.png
+REM -- color with alpha-channel
+pnm2png.exe -alpha rawn6a08.pgm rawn6a08.ppm rawn6a08.png
+pnm2png.exe -alpha rawn6a16.pgm rawn6a16.ppm rawn6a16.png
+
diff --git a/gs/libpng/contrib/pngminus/pnm2png.c b/gs/libpng/contrib/pngminus/pnm2png.c
new file mode 100644
index 000000000..4cdfad831
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/pnm2png.c
@@ -0,0 +1,533 @@
+/*
+ *  pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file
+ *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
+ *
+ *  version 1.0 - 1999.10.15 - First version.
+ *
+ *  Permission to use, copy, modify, and distribute this software and
+ *  its documentation for any purpose and without fee is hereby granted,
+ *  provided that the above copyright notice appear in all copies and
+ *  that both that copyright notice and this permission notice appear in
+ *  supporting documentation. This software is provided "as is" without
+ *  express or implied warranty.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef __TURBOC__
+#include <mem.h>
+#include <fcntl.h>
+#endif
+
+#ifndef BOOL
+#define BOOL unsigned char
+#endif
+#ifndef TRUE
+#define TRUE (BOOL) 1
+#endif
+#ifndef FALSE
+#define FALSE (BOOL) 0
+#endif
+
+#define STDIN  0
+#define STDOUT 1
+#define STDERR 2
+
+/* to make pnm2png verbose so we can find problems (needs to be before png.h) */
+#ifndef PNG_DEBUG
+#define PNG_DEBUG 0
+#endif
+
+#include "png.h"
+
+/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
+#ifndef png_jmpbuf
+#  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
+#endif
+
+/* function prototypes */
+
+int  main (int argc, char *argv[]);
+void usage ();
+BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha);
+void get_token(FILE *pnm_file, char *token);
+png_uint_32 get_data (FILE *pnm_file, int depth);
+png_uint_32 get_value (FILE *pnm_file, int depth);
+
+/*
+ *  main
+ */
+
+int main(int argc, char *argv[])
+{
+  FILE *fp_rd = stdin;
+  FILE *fp_al = NULL;
+  FILE *fp_wr = stdout;
+  BOOL interlace = FALSE;
+  BOOL alpha = FALSE;
+  int argi;
+
+  for (argi = 1; argi < argc; argi++)
+  {
+    if (argv[argi][0] == '-')
+    {
+      switch (argv[argi][1])
+      {
+        case 'i':
+          interlace = TRUE;
+          break;
+        case 'a':
+          alpha = TRUE;
+          argi++;
+          if ((fp_al = fopen (argv[argi], "rb")) == NULL)
+          {
+            fprintf (stderr, "PNM2PNG\n");
+            fprintf (stderr, "Error:  alpha-channel file %s does not exist\n",
+               argv[argi]);
+            exit (1);
+          }
+          break;
+        case 'h':
+        case '?':
+          usage();
+          exit(0);
+          break;
+        default:
+          fprintf (stderr, "PNM2PNG\n");
+          fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);
+          usage();
+          exit(1);
+          break;
+      } /* end switch */
+    }
+    else if (fp_rd == stdin)
+    {
+      if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
+      {
+        fprintf (stderr, "PNM2PNG\n");
+        fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);
+        exit (1);
+      }
+    }
+    else if (fp_wr == stdout)
+    {
+      if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
+      {
+        fprintf (stderr, "PNM2PNG\n");
+        fprintf (stderr, "Error:  can not create PNG-file %s\n", argv[argi]);
+        exit (1);
+      }
+    }
+    else
+    {
+      fprintf (stderr, "PNM2PNG\n");
+      fprintf (stderr, "Error:  too many parameters\n");
+      usage();
+      exit (1);
+    }
+  } /* end for */
+
+#ifdef __TURBOC__
+  /* set stdin/stdout to binary, we're reading the PNM always! in binary format */
+  if (fp_rd == stdin)
+  {
+    setmode (STDIN, O_BINARY);
+  }
+  if (fp_wr == stdout)
+  {
+    setmode (STDOUT, O_BINARY);
+  }
+#endif
+
+  /* call the conversion program itself */
+  if (pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha) == FALSE)
+  {
+    fprintf (stderr, "PNM2PNG\n");
+    fprintf (stderr, "Error:  unsuccessful converting to PNG-image\n");
+    exit (1);
+  }
+
+  /* close input file */
+  fclose (fp_rd);
+  /* close output file */
+  fclose (fp_wr);
+  /* close alpha file */
+  if (alpha)
+    fclose (fp_al);
+
+  return 0;
+}
+
+/*
+ *  usage
+ */
+
+void usage()
+{
+  fprintf (stderr, "PNM2PNG\n");
+  fprintf (stderr, "   by Willem van Schaik, 1999\n");
+#ifdef __TURBOC__
+  fprintf (stderr, "   for Turbo-C and Borland-C compilers\n");
+#else
+  fprintf (stderr, "   for Linux (and Unix) compilers\n");
+#endif
+  fprintf (stderr, "Usage:  pnm2png [options] <file>.<pnm> [<file>.png]\n");
+  fprintf (stderr, "   or:  ... | pnm2png [options]\n");
+  fprintf (stderr, "Options:\n");
+  fprintf (stderr, "   -i[nterlace]   write png-file with interlacing on\n");
+  fprintf (stderr, "   -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");
+  fprintf (stderr, "   -h | -?  print this help-information\n");
+}
+
+/*
+ *  pnm2png
+ */
+
+BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha)
+{
+  png_struct    *png_ptr = NULL;
+  png_info      *info_ptr = NULL;
+  png_byte      *png_pixels = NULL;
+  png_byte      **row_pointers = NULL;
+  png_byte      *pix_ptr = NULL;
+  png_uint_32   row_bytes;
+
+  char          type_token[16];
+  char          width_token[16];
+  char          height_token[16];
+  char          maxval_token[16];
+  int           color_type;
+  png_uint_32   width, alpha_width;
+  png_uint_32   height, alpha_height;
+  png_uint_32   maxval;
+  int           bit_depth = 0;
+  int           channels;
+  int           alpha_depth = 0;
+  int           alpha_present;
+  int           row, col;
+  BOOL          raw, alpha_raw = FALSE;
+  png_uint_32   tmp16;
+  int           i;
+
+  /* read header of PNM file */
+
+  get_token(pnm_file, type_token);
+  if (type_token[0] != 'P')
+  {
+    return FALSE;
+  }
+  else if ((type_token[1] == '1') || (type_token[1] == '4'))
+  {
+    raw = (type_token[1] == '4');
+    color_type = PNG_COLOR_TYPE_GRAY;
+    bit_depth = 1;
+  }
+  else if ((type_token[1] == '2') || (type_token[1] == '5'))
+  {
+    raw = (type_token[1] == '5');
+    color_type = PNG_COLOR_TYPE_GRAY;
+    get_token(pnm_file, width_token);
+    sscanf (width_token, "%lu", &width);
+    get_token(pnm_file, height_token);
+    sscanf (height_token, "%lu", &height);
+    get_token(pnm_file, maxval_token);
+    sscanf (maxval_token, "%lu", &maxval);
+    if (maxval <= 1)
+      bit_depth = 1;
+    else if (maxval <= 3)
+      bit_depth = 2;
+    else if (maxval <= 15)
+      bit_depth = 4;
+    else if (maxval <= 255)
+      bit_depth = 8;
+    else /* if (maxval <= 65535) */
+      bit_depth = 16;
+  }
+  else if ((type_token[1] == '3') || (type_token[1] == '6'))
+  {
+    raw = (type_token[1] == '6');
+    color_type = PNG_COLOR_TYPE_RGB;
+    get_token(pnm_file, width_token);
+    sscanf (width_token, "%lu", &width);
+    get_token(pnm_file, height_token);
+    sscanf (height_token, "%lu", &height);
+    get_token(pnm_file, maxval_token);
+    sscanf (maxval_token, "%lu", &maxval);
+    if (maxval <= 1)
+      bit_depth = 1;
+    else if (maxval <= 3)
+      bit_depth = 2;
+    else if (maxval <= 15)
+      bit_depth = 4;
+    else if (maxval <= 255)
+      bit_depth = 8;
+    else /* if (maxval <= 65535) */
+      bit_depth = 16;
+  }
+  else
+  {
+    return FALSE;
+  }
+
+  /* read header of PGM file with alpha channel */
+
+  if (alpha)
+  {
+    if (color_type == PNG_COLOR_TYPE_GRAY)
+      color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
+    if (color_type == PNG_COLOR_TYPE_RGB)
+      color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+
+    get_token(alpha_file, type_token);
+    if (type_token[0] != 'P')
+    {
+      return FALSE;
+    }
+    else if ((type_token[1] == '2') || (type_token[1] == '5'))
+    {
+      alpha_raw = (type_token[1] == '5');
+      get_token(alpha_file, width_token);
+      sscanf (width_token, "%lu", &alpha_width);
+      if (alpha_width != width)
+        return FALSE;
+      get_token(alpha_file, height_token);
+      sscanf (height_token, "%lu", &alpha_height);
+      if (alpha_height != height)
+        return FALSE;
+      get_token(alpha_file, maxval_token);
+      sscanf (maxval_token, "%lu", &maxval);
+      if (maxval <= 1)
+        alpha_depth = 1;
+      else if (maxval <= 3)
+        alpha_depth = 2;
+      else if (maxval <= 15)
+        alpha_depth = 4;
+      else if (maxval <= 255)
+        alpha_depth = 8;
+      else /* if (maxval <= 65535) */
+        alpha_depth = 16;
+      if (alpha_depth != bit_depth)
+        return FALSE;
+    }
+    else
+    {
+      return FALSE;
+    }
+  } /* end if alpha */
+
+  /* calculate the number of channels and store alpha-presence */
+  if (color_type == PNG_COLOR_TYPE_GRAY)
+    channels = 1;
+  else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+    channels = 2;
+  else if (color_type == PNG_COLOR_TYPE_RGB)
+    channels = 3;
+  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+    channels = 4;
+  else
+    channels = 0; /* should not happen */
+
+  alpha_present = (channels - 1) % 2;
+
+  /* row_bytes is the width x number of channels x (bit-depth / 8) */
+  row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
+
+  if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL)
+    return FALSE;
+
+  /* read data from PNM file */
+  pix_ptr = png_pixels;
+
+  for (row = 0; row < height; row++)
+  {
+    for (col = 0; col < width; col++)
+    {
+      for (i = 0; i < (channels - alpha_present); i++)
+      {
+        if (raw)
+          *pix_ptr++ = get_data (pnm_file, bit_depth);
+        else
+          if (bit_depth <= 8)
+            *pix_ptr++ = get_value (pnm_file, bit_depth);
+          else
+          {
+            tmp16 = get_value (pnm_file, bit_depth);
+            *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
+            pix_ptr++;
+            *pix_ptr = (png_byte) (tmp16 & 0xFF);
+            pix_ptr++;
+          }
+      }
+
+      if (alpha) /* read alpha-channel from pgm file */
+      {
+        if (alpha_raw)
+          *pix_ptr++ = get_data (alpha_file, alpha_depth);
+        else
+          if (alpha_depth <= 8)
+            *pix_ptr++ = get_value (alpha_file, bit_depth);
+          else
+          {
+            tmp16 = get_value (alpha_file, bit_depth);
+            *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
+            *pix_ptr++ = (png_byte) (tmp16 & 0xFF);
+          }
+      } /* if alpha */
+
+    } /* end for col */
+  } /* end for row */
+
+  /* prepare the standard PNG structures */
+  png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+  if (!png_ptr)
+  {
+    return FALSE;
+  }
+  info_ptr = png_create_info_struct (png_ptr);
+  if (!info_ptr)
+  {
+    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+    return FALSE;
+  }
+
+  /* setjmp() must be called in every function that calls a PNG-reading libpng function */
+  if (setjmp (png_jmpbuf(png_ptr)))
+  {
+    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+    return FALSE;
+  }
+
+  /* initialize the png structure */
+  png_init_io (png_ptr, png_file);
+
+  /* we're going to write more or less the same PNG as the input file */
+  png_set_IHDR (png_ptr, info_ptr, width, height, bit_depth, color_type,
+    (!interlace) ? PNG_INTERLACE_NONE : PNG_INTERLACE_ADAM7,
+    PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+  /* write the file header information */
+  png_write_info (png_ptr, info_ptr);
+
+  /* if needed we will allocate memory for an new array of row-pointers */
+  if (row_pointers == (unsigned char**) NULL)
+  {
+    if ((row_pointers = (png_byte **) malloc (height * sizeof (png_bytep))) == NULL)
+    {
+      png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+      return FALSE;
+    }
+  }
+
+  /* set the individual row_pointers to point at the correct offsets */
+  for (i = 0; i < (height); i++)
+    row_pointers[i] = png_pixels + i * row_bytes;
+
+  /* write out the entire image data in one call */
+  png_write_image (png_ptr, row_pointers);
+
+  /* write the additional chuncks to the PNG file (not really needed) */
+  png_write_end (png_ptr, info_ptr);
+
+  /* clean up after the write, and free any memory allocated */
+  png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+
+  if (row_pointers != (unsigned char**) NULL)
+    free (row_pointers);
+  if (png_pixels != (unsigned char*) NULL)
+    free (png_pixels);
+
+  return TRUE;
+} /* end of pnm2png */
+
+/*
+ * get_token() - gets the first string after whitespace
+ */
+
+void get_token(FILE *pnm_file, char *token)
+{
+  int i = 0;
+
+  /* remove white-space */
+  do
+  {
+    token[i] = (unsigned char) fgetc (pnm_file);
+  }
+  while ((token[i] == '\n') || (token[i] == '\r') || (token[i] == ' '));
+
+  /* read string */
+  do
+  {
+    i++;
+    token[i] = (unsigned char) fgetc (pnm_file);
+  }
+  while ((token[i] != '\n') && (token[i] != '\r') && (token[i] != ' '));
+
+  token[i] = '\0';
+
+  return;
+}
+
+/*
+ * get_data() - takes first byte and converts into next pixel value,
+ *        taking as much bits as defined by bit-depth and
+ *        using the bit-depth to fill up a byte (0Ah -> AAh)
+ */
+
+png_uint_32 get_data (FILE *pnm_file, int depth)
+{
+  static int bits_left = 0;
+  static int old_value = 0;
+  static int mask = 0;
+  int i;
+  png_uint_32 ret_value;
+
+  if (mask == 0)
+    for (i = 0; i < depth; i++)
+      mask = (mask >> 1) | 0x80;
+
+  if (bits_left <= 0)
+  {
+    old_value = fgetc (pnm_file);
+    bits_left = 8;
+  }
+
+  ret_value = old_value & mask;
+  for (i = 1; i < (8 / depth); i++)
+    ret_value = ret_value || (ret_value >> depth);
+
+  old_value = (old_value << depth) & 0xFF;
+  bits_left -= depth;
+
+  return ret_value;
+}
+
+/*
+ * get_value() - takes first (numeric) string and converts into number,
+ *         using the bit-depth to fill up a byte (0Ah -> AAh)
+ */
+
+png_uint_32 get_value (FILE *pnm_file, int depth)
+{
+  static png_uint_32 mask = 0;
+  png_byte token[16];
+  png_uint_32 ret_value;
+  int i = 0;
+
+  if (mask == 0)
+    for (i = 0; i < depth; i++)
+      mask = (mask << 1) | 0x01;
+
+  get_token (pnm_file, (char *) token);
+  sscanf ((const char *) token, "%lu", &ret_value);
+
+  ret_value &= mask;
+
+  if (depth < 8)
+    for (i = 0; i < (8 / depth); i++)
+      ret_value = (ret_value << depth) || ret_value;
+
+  return ret_value;
+}
+
+/* end of source */
+
diff --git a/gs/libpng/contrib/pngminus/pnm2png.sh b/gs/libpng/contrib/pngminus/pnm2png.sh
new file mode 100644
index 000000000..5afda9fb9
--- /dev/null
+++ b/gs/libpng/contrib/pngminus/pnm2png.sh
@@ -0,0 +1,41 @@
+# -- grayscale
+./pnm2png basn0g01.pgm basn0g01.png
+./pnm2png basn0g02.pgm basn0g02.png
+./pnm2png basn0g04.pgm basn0g04.png
+./pnm2png basn0g08.pgm basn0g08.png
+./pnm2png basn0g16.pgm basn0g16.png
+# -- full-color
+./pnm2png basn2c08.ppm basn2c08.png
+./pnm2png basn2c16.ppm basn2c16.png
+# -- palletted
+./pnm2png basn3p01.ppm basn3p01.png
+./pnm2png basn3p02.ppm basn3p02.png
+./pnm2png basn3p04.ppm basn3p04.png
+./pnm2png basn3p08.ppm basn3p08.png
+# -- gray with alpha-channel
+./pnm2png -alpha basn6a08.pgm basn4a08.pgm basn4a08.png
+./pnm2png -alpha basn6a16.pgm basn4a16.pgm basn4a16.png
+# -- color with alpha-channel
+./pnm2png -alpha basn6a08.pgm basn6a08.ppm basn6a08.png
+./pnm2png -alpha basn6a16.pgm basn6a16.ppm basn6a16.png
+# -- grayscale
+./pnm2png rawn0g01.pgm rawn0g01.png
+./pnm2png rawn0g02.pgm rawn0g02.png
+./pnm2png rawn0g04.pgm rawn0g04.png
+./pnm2png rawn0g08.pgm rawn0g08.png
+./pnm2png rawn0g16.pgm rawn0g16.png
+# -- full-color
+./pnm2png rawn2c08.ppm rawn2c08.png
+./pnm2png rawn2c16.ppm rawn2c16.png
+# -- palletted
+./pnm2png rawn3p01.ppm rawn3p01.png
+./pnm2png rawn3p02.ppm rawn3p02.png
+./pnm2png rawn3p04.ppm rawn3p04.png
+./pnm2png rawn3p08.ppm rawn3p08.png
+# -- gray with alpha-channel
+./pnm2png -alpha rawn6a08.pgm rawn4a08.pgm rawn4a08.png
+./pnm2png -alpha rawn6a16.pgm rawn4a16.pgm rawn4a16.png
+# -- color with alpha-channel
+./pnm2png -alpha rawn6a08.pgm rawn6a08.ppm rawn6a08.png
+./pnm2png -alpha rawn6a16.pgm rawn6a16.ppm rawn6a16.png
+
diff --git a/gs/libpng/contrib/pngsuite/README b/gs/libpng/contrib/pngsuite/README
new file mode 100644
index 000000000..714d12c64
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/README
@@ -0,0 +1,85 @@
+
+pngsuite
+--------
+(c) Willem van Schaik, 1999
+
+Permission to use, copy, and distribute these images for any purpose and
+without fee is hereby granted.
+
+These 15 images are part of the much larger PngSuite test-set of 
+images, available for developers of PNG supporting software. The 
+complete set, available at http:/www.schaik.com/pngsuite/, contains 
+a variety of images to test interlacing, gamma settings, ancillary
+chunks, etc.
+
+The images in this directory represent the basic PNG color-types:
+grayscale (1-16 bit deep), full color (8 or 16 bit), paletted
+(1-8 bit) and grayscale or color images with alpha channel. You
+can use them to test the proper functioning of PNG software.
+
+    filename      depth type
+    ------------ ------ --------------
+    basn0g01.png  1-bit grayscale
+    basn0g02.png  2-bit grayscale
+    basn0g04.png  4-bit grayscale
+    basn0g08.png  8-bit grayscale
+    basn0g16.png 16-bit grayscale
+    basn2c08.png  8-bit truecolor
+    basn2c16.png 16-bit truecolor
+    basn3p01.png  1-bit paletted
+    basn3p02.png  2-bit paletted
+    basn3p04.png  4-bit paletted
+    basn3p08.png  8-bit paletted
+    basn4a08.png  8-bit gray with alpha
+    basn4a16.png 16-bit gray with alpha
+    basn6a08.png  8-bit RGBA
+    basn6a16.png 16-bit RGBA
+
+Here is the correct result of typing "pngtest -m *.png" in
+this directory:
+
+Testing basn0g01.png: PASS (524 zero samples)
+ Filter 0 was used 32 times
+Testing basn0g02.png: PASS (448 zero samples)
+ Filter 0 was used 32 times
+Testing basn0g04.png: PASS (520 zero samples)
+ Filter 0 was used 32 times
+Testing basn0g08.png: PASS (3 zero samples)
+ Filter 1 was used 9 times
+ Filter 4 was used 23 times
+Testing basn0g16.png: PASS (1 zero samples)
+ Filter 1 was used 1 times
+ Filter 2 was used 31 times
+Testing basn2c08.png: PASS (6 zero samples)
+ Filter 1 was used 5 times
+ Filter 4 was used 27 times
+Testing basn2c16.png: PASS (592 zero samples)
+ Filter 1 was used 1 times
+ Filter 4 was used 31 times
+Testing basn3p01.png: PASS (512 zero samples)
+ Filter 0 was used 32 times
+Testing basn3p02.png: PASS (448 zero samples)
+ Filter 0 was used 32 times
+Testing basn3p04.png: PASS (544 zero samples)
+ Filter 0 was used 32 times
+Testing basn3p08.png: PASS (4 zero samples)
+ Filter 0 was used 32 times
+Testing basn4a08.png: PASS (32 zero samples)
+ Filter 1 was used 1 times
+ Filter 4 was used 31 times
+Testing basn4a16.png: PASS (64 zero samples)
+ Filter 0 was used 1 times
+ Filter 1 was used 2 times
+ Filter 2 was used 1 times
+ Filter 4 was used 28 times
+Testing basn6a08.png: PASS (160 zero samples)
+ Filter 1 was used 1 times
+ Filter 4 was used 31 times
+Testing basn6a16.png: PASS (1072 zero samples)
+ Filter 1 was used 4 times
+ Filter 4 was used 28 times
+libpng passes test
+
+Willem van Schaik
+<willem@schaik.com>
+October 1999
diff --git a/gs/libpng/contrib/pngsuite/basn0g01.png b/gs/libpng/contrib/pngsuite/basn0g01.png
new file mode 100644
index 000000000..1d722423a
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn0g01.png
diff --git a/gs/libpng/contrib/pngsuite/basn0g02.png b/gs/libpng/contrib/pngsuite/basn0g02.png
new file mode 100644
index 000000000..508332418
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn0g02.png
diff --git a/gs/libpng/contrib/pngsuite/basn0g04.png b/gs/libpng/contrib/pngsuite/basn0g04.png
new file mode 100644
index 000000000..0bf368786
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn0g04.png
diff --git a/gs/libpng/contrib/pngsuite/basn0g08.png b/gs/libpng/contrib/pngsuite/basn0g08.png
new file mode 100644
index 000000000..23c82379a
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn0g08.png
diff --git a/gs/libpng/contrib/pngsuite/basn0g16.png b/gs/libpng/contrib/pngsuite/basn0g16.png
new file mode 100644
index 000000000..e7c82f78e
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn0g16.png
diff --git a/gs/libpng/contrib/pngsuite/basn2c08.png b/gs/libpng/contrib/pngsuite/basn2c08.png
new file mode 100644
index 000000000..db5ad1586
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn2c08.png
diff --git a/gs/libpng/contrib/pngsuite/basn2c16.png b/gs/libpng/contrib/pngsuite/basn2c16.png
new file mode 100644
index 000000000..50c1cb91a
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn2c16.png
diff --git a/gs/libpng/contrib/pngsuite/basn3p01.png b/gs/libpng/contrib/pngsuite/basn3p01.png
new file mode 100644
index 000000000..b145c2b8e
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn3p01.png
diff --git a/gs/libpng/contrib/pngsuite/basn3p02.png b/gs/libpng/contrib/pngsuite/basn3p02.png
new file mode 100644
index 000000000..8985b3d81
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn3p02.png
diff --git a/gs/libpng/contrib/pngsuite/basn3p04.png b/gs/libpng/contrib/pngsuite/basn3p04.png
new file mode 100644
index 000000000..0fbf9e827
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn3p04.png
diff --git a/gs/libpng/contrib/pngsuite/basn3p08.png b/gs/libpng/contrib/pngsuite/basn3p08.png
new file mode 100644
index 000000000..0ddad07e5
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn3p08.png
diff --git a/gs/libpng/contrib/pngsuite/basn4a08.png b/gs/libpng/contrib/pngsuite/basn4a08.png
new file mode 100644
index 000000000..3e1305220
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn4a08.png
diff --git a/gs/libpng/contrib/pngsuite/basn4a16.png b/gs/libpng/contrib/pngsuite/basn4a16.png
new file mode 100644
index 000000000..8243644d0
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn4a16.png
diff --git a/gs/libpng/contrib/pngsuite/basn6a08.png b/gs/libpng/contrib/pngsuite/basn6a08.png
new file mode 100644
index 000000000..e60873876
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn6a08.png
diff --git a/gs/libpng/contrib/pngsuite/basn6a16.png b/gs/libpng/contrib/pngsuite/basn6a16.png
new file mode 100644
index 000000000..984a99525
--- /dev/null
+++ b/gs/libpng/contrib/pngsuite/basn6a16.png
diff --git a/gs/libpng/contrib/visupng/PngFile.c b/gs/libpng/contrib/visupng/PngFile.c
new file mode 100644
index 000000000..959afe9de
--- /dev/null
+++ b/gs/libpng/contrib/visupng/PngFile.c
@@ -0,0 +1,439 @@
+//-------------------------------------
+//  PNGFILE.C -- Image File Functions
+//-------------------------------------
+
+// Copyright 2000, Willem van Schaik.  For conditions of distribution and
+// use, see the copyright/license/disclaimer notice in png.h
+
+#include <windows.h>
+#include <commdlg.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "png.h"
+#include "pngfile.h"
+#include "cexcept.h"
+
+define_exception_type(const char *);
+extern struct exception_context the_exception_context[1];
+struct exception_context the_exception_context[1];
+png_const_charp msg;
+
+static OPENFILENAME ofn;
+
+static png_structp png_ptr = NULL;
+static png_infop info_ptr = NULL;
+
+
+// cexcept interface
+
+static void
+png_cexcept_error(png_structp png_ptr, png_const_charp msg)
+{
+   if(png_ptr)
+     ;
+#ifndef PNG_NO_CONSOLE_IO
+   fprintf(stderr, "libpng error: %s\n", msg);
+#endif
+   {
+      Throw msg;
+   }
+}
+
+// Windows open-file functions
+
+void PngFileInitialize (HWND hwnd)
+{
+    static TCHAR szFilter[] = TEXT ("PNG Files (*.PNG)\0*.png\0")
+        TEXT ("All Files (*.*)\0*.*\0\0");
+
+    ofn.lStructSize       = sizeof (OPENFILENAME);
+    ofn.hwndOwner         = hwnd;
+    ofn.hInstance         = NULL;
+    ofn.lpstrFilter       = szFilter;
+    ofn.lpstrCustomFilter = NULL;
+    ofn.nMaxCustFilter    = 0;
+    ofn.nFilterIndex      = 0;
+    ofn.lpstrFile         = NULL;          // Set in Open and Close functions
+    ofn.nMaxFile          = MAX_PATH;
+    ofn.lpstrFileTitle    = NULL;          // Set in Open and Close functions
+    ofn.nMaxFileTitle     = MAX_PATH;
+    ofn.lpstrInitialDir   = NULL;
+    ofn.lpstrTitle        = NULL;
+    ofn.Flags             = 0;             // Set in Open and Close functions
+    ofn.nFileOffset       = 0;
+    ofn.nFileExtension    = 0;
+    ofn.lpstrDefExt       = TEXT ("png");
+    ofn.lCustData         = 0;
+    ofn.lpfnHook          = NULL;
+    ofn.lpTemplateName    = NULL;
+}
+
+BOOL PngFileOpenDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName)
+{
+    ofn.hwndOwner         = hwnd;
+    ofn.lpstrFile         = pstrFileName;
+    ofn.lpstrFileTitle    = pstrTitleName;
+    ofn.Flags             = OFN_HIDEREADONLY;
+
+    return GetOpenFileName (&ofn);
+}
+
+BOOL PngFileSaveDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName)
+{
+    ofn.hwndOwner         = hwnd;
+    ofn.lpstrFile         = pstrFileName;
+    ofn.lpstrFileTitle    = pstrTitleName;
+    ofn.Flags             = OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT;
+
+    return GetSaveFileName (&ofn);
+}
+
+// PNG image handler functions
+
+BOOL PngLoadImage (PTSTR pstrFileName, png_byte **ppbImageData,
+                   int *piWidth, int *piHeight, int *piChannels, png_color *pBkgColor)
+{
+    static FILE        *pfFile;
+    png_byte            pbSig[8];
+    int                 iBitDepth;
+    int                 iColorType;
+    double              dGamma;
+    png_color_16       *pBackground;
+    png_uint_32         ulChannels;
+    png_uint_32         ulRowBytes;
+    png_byte           *pbImageData = *ppbImageData;
+    static png_byte   **ppbRowPointers = NULL;
+    int                 i;
+
+    // open the PNG input file
+
+    if (!pstrFileName)
+    {
+        *ppbImageData = pbImageData = NULL;
+        return FALSE;
+    }
+
+    if (!(pfFile = fopen(pstrFileName, "rb")))
+    {
+        *ppbImageData = pbImageData = NULL;
+        return FALSE;
+    }
+
+    // first check the eight byte PNG signature
+
+    fread(pbSig, 1, 8, pfFile);
+    if (!png_check_sig(pbSig, 8))
+    {
+        *ppbImageData = pbImageData = NULL;
+        return FALSE;
+    }
+
+    // create the two png(-info) structures
+
+    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL,
+      (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL);
+    if (!png_ptr)
+    {
+        *ppbImageData = pbImageData = NULL;
+        return FALSE;
+    }
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr)
+    {
+        png_destroy_read_struct(&png_ptr, NULL, NULL);
+        *ppbImageData = pbImageData = NULL;
+        return FALSE;
+    }
+
+    Try
+    {
+        
+        // initialize the png structure
+        
+#if !defined(PNG_NO_STDIO)
+        png_init_io(png_ptr, pfFile);
+#else
+        png_set_read_fn(png_ptr, (png_voidp)pfFile, png_read_data);
+#endif
+        
+        png_set_sig_bytes(png_ptr, 8);
+        
+        // read all PNG info up to image data
+        
+        png_read_info(png_ptr, info_ptr);
+        
+        // get width, height, bit-depth and color-type
+        
+        png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth,
+            &iColorType, NULL, NULL, NULL);
+        
+        // expand images of all color-type and bit-depth to 3x8 bit RGB images
+        // let the library process things like alpha, transparency, background
+        
+        if (iBitDepth == 16)
+            png_set_strip_16(png_ptr);
+        if (iColorType == PNG_COLOR_TYPE_PALETTE)
+            png_set_expand(png_ptr);
+        if (iBitDepth < 8)
+            png_set_expand(png_ptr);
+        if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+            png_set_expand(png_ptr);
+        if (iColorType == PNG_COLOR_TYPE_GRAY ||
+            iColorType == PNG_COLOR_TYPE_GRAY_ALPHA)
+            png_set_gray_to_rgb(png_ptr);
+        
+        // set the background color to draw transparent and alpha images over.
+        if (png_get_bKGD(png_ptr, info_ptr, &pBackground))
+        {
+            png_set_background(png_ptr, pBackground, PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
+            pBkgColor->red   = (byte) pBackground->red;
+            pBkgColor->green = (byte) pBackground->green;
+            pBkgColor->blue  = (byte) pBackground->blue;
+        }
+        else
+        {
+            pBkgColor = NULL;
+        }
+        
+        // if required set gamma conversion
+        if (png_get_gAMA(png_ptr, info_ptr, &dGamma))
+            png_set_gamma(png_ptr, (double) 2.2, dGamma);
+        
+        // after the transformations have been registered update info_ptr data
+        
+        png_read_update_info(png_ptr, info_ptr);
+        
+        // get again width, height and the new bit-depth and color-type
+        
+        png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth,
+            &iColorType, NULL, NULL, NULL);
+        
+        
+        // row_bytes is the width x number of channels
+        
+        ulRowBytes = png_get_rowbytes(png_ptr, info_ptr);
+        ulChannels = png_get_channels(png_ptr, info_ptr);
+        
+        *piChannels = ulChannels;
+        
+        // now we can allocate memory to store the image
+        
+        if (pbImageData)
+        {
+            free (pbImageData);
+            pbImageData = NULL;
+        }
+        if ((pbImageData = (png_byte *) malloc(ulRowBytes * (*piHeight)
+                            * sizeof(png_byte))) == NULL)
+        {
+            png_error(png_ptr, "Visual PNG: out of memory");
+        }
+        *ppbImageData = pbImageData;
+        
+        // and allocate memory for an array of row-pointers
+        
+        if ((ppbRowPointers = (png_bytepp) malloc((*piHeight)
+                            * sizeof(png_bytep))) == NULL)
+        {
+            png_error(png_ptr, "Visual PNG: out of memory");
+        }
+        
+        // set the individual row-pointers to point at the correct offsets
+        
+        for (i = 0; i < (*piHeight); i++)
+            ppbRowPointers[i] = pbImageData + i * ulRowBytes;
+        
+        // now we can go ahead and just read the whole image
+        
+        png_read_image(png_ptr, ppbRowPointers);
+        
+        // read the additional chunks in the PNG file (not really needed)
+        
+        png_read_end(png_ptr, NULL);
+        
+        // and we're done
+        
+        free (ppbRowPointers);
+        ppbRowPointers = NULL;
+        
+        // yepp, done
+    }
+
+    Catch (msg)
+    {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+
+        *ppbImageData = pbImageData = NULL;
+        
+        if(ppbRowPointers)
+            free (ppbRowPointers);
+
+        fclose(pfFile);
+
+        return FALSE;
+    }
+
+    fclose (pfFile);
+
+    return TRUE;
+}
+
+
+BOOL PngSaveImage (PTSTR pstrFileName, png_byte *pDiData,
+                   int iWidth, int iHeight, png_color bkgColor)
+{
+    const int           ciBitDepth = 8;
+    const int           ciChannels = 3;
+
+    static FILE        *pfFile;
+    png_uint_32         ulRowBytes;
+    static png_byte   **ppbRowPointers = NULL;
+    int                 i;
+
+    // open the PNG output file
+
+    if (!pstrFileName)
+        return FALSE;
+
+    if (!(pfFile = fopen(pstrFileName, "wb")))
+        return FALSE;
+
+    // prepare the standard PNG structures
+
+    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL,
+      (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL);
+    if (!png_ptr)
+    {
+        fclose(pfFile);
+        return FALSE;
+    }
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        fclose(pfFile);
+        png_destroy_write_struct(&png_ptr, (png_infopp) NULL);
+        return FALSE;
+    }
+
+    Try
+    {
+        // initialize the png structure
+        
+#if !defined(PNG_NO_STDIO)
+        png_init_io(png_ptr, pfFile);
+#else
+        png_set_write_fn(png_ptr, (png_voidp)pfFile, png_write_data, png_flush);
+#endif
+        
+        // we're going to write a very simple 3x8 bit RGB image
+        
+        png_set_IHDR(png_ptr, info_ptr, iWidth, iHeight, ciBitDepth,
+            PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE,
+            PNG_FILTER_TYPE_BASE);
+        
+        // write the file header information
+        
+        png_write_info(png_ptr, info_ptr);
+        
+        // swap the BGR pixels in the DiData structure to RGB
+        
+        png_set_bgr(png_ptr);
+        
+        // row_bytes is the width x number of channels
+        
+        ulRowBytes = iWidth * ciChannels;
+        
+        // we can allocate memory for an array of row-pointers
+        
+        if ((ppbRowPointers = (png_bytepp) malloc(iHeight * sizeof(png_bytep))) == NULL)
+            Throw "Visualpng: Out of memory";
+        
+        // set the individual row-pointers to point at the correct offsets
+        
+        for (i = 0; i < iHeight; i++)
+            ppbRowPointers[i] = pDiData + i * (((ulRowBytes + 3) >> 2) << 2);
+        
+        // write out the entire image data in one call
+        
+        png_write_image (png_ptr, ppbRowPointers);
+        
+        // write the additional chunks to the PNG file (not really needed)
+        
+        png_write_end(png_ptr, info_ptr);
+        
+        // and we're done
+        
+        free (ppbRowPointers);
+        ppbRowPointers = NULL;
+        
+        // clean up after the write, and free any memory allocated
+        
+        png_destroy_write_struct(&png_ptr, (png_infopp) NULL);
+        
+        // yepp, done
+    }
+
+    Catch (msg)
+    {
+        png_destroy_write_struct(&png_ptr, (png_infopp) NULL);
+
+        if(ppbRowPointers)
+            free (ppbRowPointers);
+
+        fclose(pfFile);
+
+        return FALSE;
+    }
+    
+    fclose (pfFile);
+    
+    return TRUE;
+}
+
+#ifdef PNG_NO_STDIO
+
+static void
+png_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   png_size_t check;
+
+   /* fread() returns 0 on error, so it is OK to store this in a png_size_t
+    * instead of an int, which is what fread() actually returns.
+    */
+   check = (png_size_t)fread(data, (png_size_t)1, length,
+      (FILE *)png_ptr->io_ptr);
+
+   if (check != length)
+   {
+      png_error(png_ptr, "Read Error");
+   }
+}
+
+static void
+png_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   png_uint_32 check;
+
+   check = fwrite(data, 1, length, (FILE *)(png_ptr->io_ptr));
+   if (check != length)
+   {
+      png_error(png_ptr, "Write Error");
+   }
+}
+
+static void
+png_flush(png_structp png_ptr)
+{
+   FILE *io_ptr;
+   io_ptr = (FILE *)CVT_PTR((png_ptr->io_ptr));
+   if (io_ptr != NULL)
+      fflush(io_ptr);
+}
+
+#endif
+
+//-----------------
+//  end of source
+//-----------------
diff --git a/gs/libpng/contrib/visupng/PngFile.h b/gs/libpng/contrib/visupng/PngFile.h
new file mode 100644
index 000000000..a900fd4fd
--- /dev/null
+++ b/gs/libpng/contrib/visupng/PngFile.h
@@ -0,0 +1,27 @@
+//------------------------------------------
+//  PNGFILE.H -- Header File for pngfile.c
+//------------------------------------------
+
+// Copyright 2000, Willem van Schaik.  For conditions of distribution and
+// use, see the copyright/license/disclaimer notice in png.h
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <windows.h>
+
+void PngFileInitialize (HWND hwnd) ;
+BOOL PngFileOpenDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName) ;
+BOOL PngFileSaveDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName) ;
+
+BOOL PngLoadImage (PTSTR pstrFileName, png_byte **ppbImageData, 
+                   int *piWidth, int *piHeight, int *piChannels, png_color *pBkgColor);
+BOOL PngSaveImage (PTSTR pstrFileName, png_byte *pDiData,
+                   int iWidth, int iHeight, png_color BkgColor);
+
+#if defined(PNG_NO_STDIO)
+static void png_read_data(png_structp png_ptr, png_bytep data, png_size_t length);
+static void png_write_data(png_structp png_ptr, png_bytep data, png_size_t length);
+static void png_flush(png_structp png_ptr);
+#endif
+
diff --git a/gs/libpng/contrib/visupng/README.txt b/gs/libpng/contrib/visupng/README.txt
new file mode 100644
index 000000000..4a753d8e2
--- /dev/null
+++ b/gs/libpng/contrib/visupng/README.txt
@@ -0,0 +1,58 @@
+Microsoft Developer Studio Build File, Format Version 6.00 for VisualPng
+------------------------------------------------------------------------
+
+Copyright 2000, Willem van Schaik.  For conditions of distribution and
+use, see the copyright/license/disclaimer notice in png.h
+
+As a PNG .dll demo VisualPng is finished. More features would only hinder
+the program's objective. However, further extensions (like support for other 
+graphics formats) are in development. To get these, or for pre-compiled 
+binaries, go to "http://www.schaik.com/png/visualpng.html".
+
+------------------------------------------------------------------------
+
+Assumes that
+
+   libpng DLLs and LIBs are in ..\..\projects\msvc\win32\libpng
+   zlib DLLs and LIBs are in   ..\..\projects\msvc\win32\zlib
+   libpng header files are in  ..\..\..\libpng
+   zlib header files are in    ..\..\..\zlib
+   the pngsuite images are in  ..\pngsuite
+
+To build:
+
+1) On the main menu Select "Build|Set Active configuration".
+   Choose the configuration that corresponds to the library you want to test.
+   This library must have been built using the libpng MS project located in
+   the "..\..\mscv" subdirectory.
+
+2) Select "Build|Clean"
+
+3) Select "Build|Rebuild All"
+
+4) After compiling and linking VisualPng will be started to view an image
+   from the PngSuite directory.  Press Ctrl-N (and Ctrl-V) for other images.
+
+
+To install:
+
+When distributing VisualPng (or a further development) the following options
+are available:
+
+1) Build the program with the configuration "Win32 LIB" and you only need to
+   include the executable from the ./lib directory in your distribution.
+
+2) Build the program with the configuration "Win32 DLL" and you need to put
+   in your distribution the executable from the ./dll directory and the dll's
+   libpng1.dll, zlib.dll and msvcrt.dll.  These need to be in the user's PATH.
+
+
+Willem van Schaik
+Calgary, June 6th 2000
+
+P.S. VisualPng was written based on preliminary work of:
+
+    - Simon-Pierre Cadieux
+    - Glenn Randers-Pehrson
+    - Greg Roelofs
+
diff --git a/gs/libpng/contrib/visupng/VisualPng.c b/gs/libpng/contrib/visupng/VisualPng.c
new file mode 100644
index 000000000..f2cf6ee9a
--- /dev/null
+++ b/gs/libpng/contrib/visupng/VisualPng.c
@@ -0,0 +1,961 @@
+//------------------------------------
+//  VisualPng.C -- Shows a PNG image
+//------------------------------------
+
+// Copyright 2000, Willem van Schaik.  For conditions of distribution and
+// use, see the copyright/license/disclaimer notice in png.h
+
+// switches
+
+// defines
+
+#define PROGNAME  "VisualPng"
+#define LONGNAME  "Win32 Viewer for PNG-files"
+#define VERSION   "1.0 of 2000 June 07"
+
+// constants
+
+#define MARGIN 8
+
+// standard includes
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <windows.h>
+
+// application includes
+
+#include "png.h"
+#include "pngfile.h"
+#include "resource.h"
+
+// macros
+
+// function prototypes
+
+LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM);
+BOOL    CALLBACK AboutDlgProc (HWND, UINT, WPARAM, LPARAM) ;
+
+BOOL CenterAbout (HWND hwndChild, HWND hwndParent);
+
+BOOL BuildPngList (PTSTR pstrPathName, TCHAR **ppFileList, int *pFileCount,
+        int *pFileIndex);
+
+BOOL SearchPngList (TCHAR *pFileList, int FileCount, int *pFileIndex,
+        PTSTR pstrPrevName, PTSTR pstrNextName);
+
+BOOL LoadImageFile(HWND hwnd, PTSTR pstrPathName,
+        png_byte **ppbImage, int *pxImgSize, int *pyImgSize, int *piChannels,
+        png_color *pBkgColor);
+
+BOOL DisplayImage (HWND hwnd, BYTE **ppDib,
+        BYTE **ppDiData, int cxWinSize, int cyWinSize,
+        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,
+        BOOL bStretched);
+
+BOOL InitBitmap (
+        BYTE *pDiData, int cxWinSize, int cyWinSize);
+
+BOOL FillBitmap (
+        BYTE *pDiData, int cxWinSize, int cyWinSize,
+        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,
+        BOOL bStretched);
+
+// a few global variables
+
+static char *szProgName = PROGNAME;
+static char *szAppName = LONGNAME;
+static char *szIconName = PROGNAME;
+static char szCmdFileName [MAX_PATH];
+
+// MAIN routine
+
+int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
+                    PSTR szCmdLine, int iCmdShow)
+{
+    HACCEL   hAccel;
+    HWND     hwnd;
+    MSG      msg;
+    WNDCLASS wndclass;
+    int ixBorders, iyBorders;
+
+    wndclass.style         = CS_HREDRAW | CS_VREDRAW;
+    wndclass.lpfnWndProc   = WndProc;
+    wndclass.cbClsExtra    = 0;
+    wndclass.cbWndExtra    = 0;
+    wndclass.hInstance     = hInstance;
+    wndclass.hIcon         = LoadIcon (hInstance, szIconName) ;
+    wndclass.hCursor       = LoadCursor (NULL, IDC_ARROW);
+    wndclass.hbrBackground = NULL; // (HBRUSH) GetStockObject (GRAY_BRUSH);
+    wndclass.lpszMenuName  = szProgName;
+    wndclass.lpszClassName = szProgName;
+
+    if (!RegisterClass (&wndclass))
+    {
+        MessageBox (NULL, TEXT ("Error: this program requires Windows NT!"),
+            szProgName, MB_ICONERROR);
+        return 0;
+    }
+
+    // if filename given on commandline, store it
+    if ((szCmdLine != NULL) && (*szCmdLine != '\0'))
+        if (szCmdLine[0] == '"')
+            strncpy (szCmdFileName, szCmdLine + 1, strlen(szCmdLine) - 2);
+        else
+            strcpy (szCmdFileName, szCmdLine);
+    else
+        strcpy (szCmdFileName, "");
+
+    // calculate size of window-borders
+    ixBorders = 2 * (GetSystemMetrics (SM_CXBORDER) +
+                     GetSystemMetrics (SM_CXDLGFRAME));
+    iyBorders = 2 * (GetSystemMetrics (SM_CYBORDER) +
+                     GetSystemMetrics (SM_CYDLGFRAME)) +
+                     GetSystemMetrics (SM_CYCAPTION) +
+                     GetSystemMetrics (SM_CYMENUSIZE) +
+                     1; /* WvS: don't ask me why? */
+
+    hwnd = CreateWindow (szProgName, szAppName,
+        WS_OVERLAPPEDWINDOW,
+        CW_USEDEFAULT, CW_USEDEFAULT,
+        512 + 2 * MARGIN + ixBorders, 384 + 2 * MARGIN + iyBorders,
+//      CW_USEDEFAULT, CW_USEDEFAULT,
+        NULL, NULL, hInstance, NULL);
+
+    ShowWindow (hwnd, iCmdShow);
+    UpdateWindow (hwnd);
+
+    hAccel = LoadAccelerators (hInstance, szProgName);
+
+    while (GetMessage (&msg, NULL, 0, 0))
+    {
+        if (!TranslateAccelerator (hwnd, hAccel, &msg))
+        {
+            TranslateMessage (&msg);
+            DispatchMessage (&msg);
+        }
+    }
+    return msg.wParam;
+}
+
+LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam,
+        LPARAM lParam)
+{
+    static HINSTANCE          hInstance ;
+    static HDC                hdc;
+    static PAINTSTRUCT        ps;
+    static HMENU              hMenu;
+
+    static BITMAPFILEHEADER  *pbmfh;
+    static BITMAPINFOHEADER  *pbmih;
+    static BYTE              *pbImage;
+    static int                cxWinSize, cyWinSize;
+    static int                cxImgSize, cyImgSize;
+    static int                cImgChannels;
+    static png_color          bkgColor = {127, 127, 127};
+
+    static BOOL               bStretched = TRUE;
+
+    static BYTE              *pDib = NULL;
+    static BYTE              *pDiData = NULL;
+
+    static TCHAR              szImgPathName [MAX_PATH];
+    static TCHAR              szTitleName [MAX_PATH];
+
+    static TCHAR             *pPngFileList = NULL;
+    static int                iPngFileCount;
+    static int                iPngFileIndex;
+
+    BOOL                      bOk;
+
+    switch (message)
+    {
+    case WM_CREATE:
+        hInstance = ((LPCREATESTRUCT) lParam)->hInstance ;
+        PngFileInitialize (hwnd);
+
+        strcpy (szImgPathName, "");
+
+        // in case we process file given on command-line
+
+        if (szCmdFileName[0] != '\0')
+        {
+            strcpy (szImgPathName, szCmdFileName);
+
+            // read the other png-files in the directory for later
+            // next/previous commands
+
+            BuildPngList (szImgPathName, &pPngFileList, &iPngFileCount,
+                          &iPngFileIndex);
+
+            // load the image from file
+
+            if (!LoadImageFile (hwnd, szImgPathName,
+                &pbImage, &cxImgSize, &cyImgSize, &cImgChannels, &bkgColor))
+                return 0;
+
+            // invalidate the client area for later update
+
+            InvalidateRect (hwnd, NULL, TRUE);
+
+            // display the PNG into the DIBitmap
+
+            DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+                pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+        }
+
+        return 0;
+
+    case WM_SIZE:
+        cxWinSize = LOWORD (lParam);
+        cyWinSize = HIWORD (lParam);
+
+        // invalidate the client area for later update
+
+        InvalidateRect (hwnd, NULL, TRUE);
+
+        // display the PNG into the DIBitmap
+
+        DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+            pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+
+        return 0;
+
+    case WM_INITMENUPOPUP:
+        hMenu = GetMenu (hwnd);
+
+        if (pbImage)
+            EnableMenuItem (hMenu, IDM_FILE_SAVE, MF_ENABLED);
+        else
+            EnableMenuItem (hMenu, IDM_FILE_SAVE, MF_GRAYED);
+
+        return 0;
+
+    case WM_COMMAND:
+        hMenu = GetMenu (hwnd);
+
+        switch (LOWORD (wParam))
+        {
+        case IDM_FILE_OPEN:
+
+            // show the File Open dialog box
+
+            if (!PngFileOpenDlg (hwnd, szImgPathName, szTitleName))
+                return 0;
+
+            // read the other png-files in the directory for later
+            // next/previous commands
+
+            BuildPngList (szImgPathName, &pPngFileList, &iPngFileCount,
+                          &iPngFileIndex);
+
+            // load the image from file
+
+            if (!LoadImageFile (hwnd, szImgPathName,
+                &pbImage, &cxImgSize, &cyImgSize, &cImgChannels, &bkgColor))
+                return 0;
+
+            // invalidate the client area for later update
+
+            InvalidateRect (hwnd, NULL, TRUE);
+
+            // display the PNG into the DIBitmap
+
+            DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+                pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+
+            return 0;
+
+        case IDM_FILE_SAVE:
+
+            // show the File Save dialog box
+
+            if (!PngFileSaveDlg (hwnd, szImgPathName, szTitleName))
+                return 0;
+
+            // save the PNG to a disk file
+
+            SetCursor (LoadCursor (NULL, IDC_WAIT));
+            ShowCursor (TRUE);
+
+            bOk = PngSaveImage (szImgPathName, pDiData, cxWinSize, cyWinSize,
+                  bkgColor);
+
+            ShowCursor (FALSE);
+            SetCursor (LoadCursor (NULL, IDC_ARROW));
+
+            if (!bOk)
+                MessageBox (hwnd, TEXT ("Error in saving the PNG image"),
+                szProgName, MB_ICONEXCLAMATION | MB_OK);
+            return 0;
+
+        case IDM_FILE_NEXT:
+
+            // read next entry in the directory
+
+            if (SearchPngList (pPngFileList, iPngFileCount, &iPngFileIndex,
+                NULL, szImgPathName))
+            {
+                if (strcmp (szImgPathName, "") == 0)
+                    return 0;
+                
+                // load the image from file
+                
+                if (!LoadImageFile (hwnd, szImgPathName, &pbImage,
+                        &cxImgSize, &cyImgSize, &cImgChannels, &bkgColor))
+                    return 0;
+                
+                // invalidate the client area for later update
+                
+                InvalidateRect (hwnd, NULL, TRUE);
+                
+                // display the PNG into the DIBitmap
+                
+                DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+                    pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+            }
+            
+            return 0;
+
+        case IDM_FILE_PREVIOUS:
+
+            // read previous entry in the directory
+
+            if (SearchPngList (pPngFileList, iPngFileCount, &iPngFileIndex,
+                szImgPathName, NULL))
+            {
+                
+                if (strcmp (szImgPathName, "") == 0)
+                    return 0;
+                
+                // load the image from file
+                
+                if (!LoadImageFile (hwnd, szImgPathName, &pbImage, &cxImgSize,
+                    &cyImgSize, &cImgChannels, &bkgColor))
+                    return 0;
+                
+                // invalidate the client area for later update
+                
+                InvalidateRect (hwnd, NULL, TRUE);
+                
+                // display the PNG into the DIBitmap
+                
+                DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+                    pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+            }
+
+            return 0;
+
+        case IDM_FILE_EXIT:
+
+            // more cleanup needed...
+
+            // free image buffer
+
+            if (pDib != NULL)
+            {
+                free (pDib);
+                pDib = NULL;
+            }
+
+            // free file-list
+
+            if (pPngFileList != NULL)
+            {
+                free (pPngFileList);
+                pPngFileList = NULL;
+            }
+
+            // let's go ...
+
+            exit (0);
+
+            return 0;
+
+        case IDM_OPTIONS_STRETCH:
+            bStretched = !bStretched;
+            if (bStretched)
+                CheckMenuItem (hMenu, IDM_OPTIONS_STRETCH, MF_CHECKED);
+            else
+                CheckMenuItem (hMenu, IDM_OPTIONS_STRETCH, MF_UNCHECKED);
+
+            // invalidate the client area for later update
+
+            InvalidateRect (hwnd, NULL, TRUE);
+
+            // display the PNG into the DIBitmap
+
+            DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+                pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+
+            return 0;
+
+        case IDM_HELP_ABOUT:
+            DialogBox (hInstance, TEXT ("AboutBox"), hwnd, AboutDlgProc) ;
+            return 0;
+
+        } // end switch
+
+        break;
+
+    case WM_PAINT:
+        hdc = BeginPaint (hwnd, &ps);
+
+        if (pDib)
+            SetDIBitsToDevice (hdc, 0, 0, cxWinSize, cyWinSize, 0, 0,
+                0, cyWinSize, pDiData, (BITMAPINFO *) pDib, DIB_RGB_COLORS);
+
+        EndPaint (hwnd, &ps);
+        return 0;
+
+    case WM_DESTROY:
+        if (pbmfh)
+        {
+            free (pbmfh);
+            pbmfh = NULL;
+        }
+
+        PostQuitMessage (0);
+        return 0;
+    }
+
+    return DefWindowProc (hwnd, message, wParam, lParam);
+}
+
+BOOL CALLBACK AboutDlgProc (HWND hDlg, UINT message,
+                            WPARAM wParam, LPARAM lParam)
+{
+     switch (message)
+     {
+     case WM_INITDIALOG :
+          ShowWindow (hDlg, SW_HIDE);
+          CenterAbout (hDlg, GetWindow (hDlg, GW_OWNER));
+          ShowWindow (hDlg, SW_SHOW);
+          return TRUE ;
+
+     case WM_COMMAND :
+          switch (LOWORD (wParam))
+          {
+          case IDOK :
+          case IDCANCEL :
+               EndDialog (hDlg, 0) ;
+               return TRUE ;
+          }
+          break ;
+     }
+     return FALSE ;
+}
+
+//---------------
+//  CenterAbout
+//---------------
+
+BOOL CenterAbout (HWND hwndChild, HWND hwndParent)
+{
+   RECT    rChild, rParent, rWorkArea;
+   int     wChild, hChild, wParent, hParent;
+   int     xNew, yNew;
+   BOOL  bResult;
+
+   // Get the Height and Width of the child window
+   GetWindowRect (hwndChild, &rChild);
+   wChild = rChild.right - rChild.left;
+   hChild = rChild.bottom - rChild.top;
+
+   // Get the Height and Width of the parent window
+   GetWindowRect (hwndParent, &rParent);
+   wParent = rParent.right - rParent.left;
+   hParent = rParent.bottom - rParent.top;
+
+   // Get the limits of the 'workarea'
+   bResult = SystemParametersInfo(
+      SPI_GETWORKAREA,  // system parameter to query or set
+      sizeof(RECT),
+      &rWorkArea,
+      0);
+   if (!bResult) {
+      rWorkArea.left = rWorkArea.top = 0;
+      rWorkArea.right = GetSystemMetrics(SM_CXSCREEN);
+      rWorkArea.bottom = GetSystemMetrics(SM_CYSCREEN);
+   }
+
+   // Calculate new X position, then adjust for workarea
+   xNew = rParent.left + ((wParent - wChild) /2);
+   if (xNew < rWorkArea.left) {
+      xNew = rWorkArea.left;
+   } else if ((xNew+wChild) > rWorkArea.right) {
+      xNew = rWorkArea.right - wChild;
+   }
+
+   // Calculate new Y position, then adjust for workarea
+   yNew = rParent.top  + ((hParent - hChild) /2);
+   if (yNew < rWorkArea.top) {
+      yNew = rWorkArea.top;
+   } else if ((yNew+hChild) > rWorkArea.bottom) {
+      yNew = rWorkArea.bottom - hChild;
+   }
+
+   // Set it, and return
+   return SetWindowPos (hwndChild, NULL, xNew, yNew, 0, 0, SWP_NOSIZE |
+          SWP_NOZORDER);
+}
+
+//----------------
+//  BuildPngList
+//----------------
+
+BOOL BuildPngList (PTSTR pstrPathName, TCHAR **ppFileList, int *pFileCount,
+     int *pFileIndex)
+{
+    static TCHAR              szImgPathName [MAX_PATH];
+    static TCHAR              szImgFileName [MAX_PATH];
+    static TCHAR              szImgFindName [MAX_PATH];
+
+    WIN32_FIND_DATA           finddata;
+    HANDLE                    hFind;
+
+    static TCHAR              szTmp [MAX_PATH];
+    BOOL                      bOk;
+    int                       i, ii;
+    int                       j, jj;
+
+    // free previous file-list
+
+    if (*ppFileList != NULL)
+    {
+        free (*ppFileList);
+        *ppFileList = NULL;
+    }
+
+    // extract foldername, filename and search-name
+
+    strcpy (szImgPathName, pstrPathName);
+    strcpy (szImgFileName, strrchr (pstrPathName, '\\') + 1);
+
+    strcpy (szImgFindName, szImgPathName);
+    *(strrchr (szImgFindName, '\\') + 1) = '\0';
+    strcat (szImgFindName, "*.png");
+
+    // first cycle: count number of files in directory for memory allocation
+
+    *pFileCount = 0;
+
+    hFind = FindFirstFile(szImgFindName, &finddata);
+    bOk = (hFind != (HANDLE) -1);
+
+    while (bOk)
+    {
+        *pFileCount += 1;
+        bOk = FindNextFile(hFind, &finddata);
+    }
+    FindClose(hFind);
+
+    // allocation memory for file-list
+
+    *ppFileList = (TCHAR *) malloc (*pFileCount * MAX_PATH);
+
+    // second cycle: read directory and store filenames in file-list
+
+    hFind = FindFirstFile(szImgFindName, &finddata);
+    bOk = (hFind != (HANDLE) -1);
+
+    i = 0;
+    ii = 0;
+    while (bOk)
+    {
+        strcpy (*ppFileList + ii, szImgPathName);
+        strcpy (strrchr(*ppFileList + ii, '\\') + 1, finddata.cFileName);
+
+        if (strcmp(pstrPathName, *ppFileList + ii) == 0)
+            *pFileIndex = i;
+
+        ii += MAX_PATH;
+        i++;
+
+        bOk = FindNextFile(hFind, &finddata);
+    }
+    FindClose(hFind);
+
+    // finally we must sort the file-list
+
+    for (i = 0; i < *pFileCount - 1; i++)
+    {
+        ii = i * MAX_PATH;
+        for (j = i+1; j < *pFileCount; j++)
+        {
+            jj = j * MAX_PATH;
+            if (strcmp (*ppFileList + ii, *ppFileList + jj) > 0)
+            {
+                strcpy (szTmp, *ppFileList + jj);
+                strcpy (*ppFileList + jj, *ppFileList + ii);
+                strcpy (*ppFileList + ii, szTmp);
+
+                // check if this was the current image that we moved
+
+                if (*pFileIndex == i)
+                    *pFileIndex = j;
+                else
+                    if (*pFileIndex == j)
+                        *pFileIndex = i;
+            }
+        }
+    }
+
+    return TRUE;
+}
+
+//----------------
+//  SearchPngList
+//----------------
+
+BOOL SearchPngList (
+        TCHAR *pFileList, int FileCount, int *pFileIndex,
+        PTSTR pstrPrevName, PTSTR pstrNextName)
+{
+    if (FileCount > 0)
+    {
+        // get previous entry
+        
+        if (pstrPrevName != NULL)
+        {
+            if (*pFileIndex > 0)
+                *pFileIndex -= 1;
+            else
+                *pFileIndex = FileCount - 1;
+            
+            strcpy (pstrPrevName, pFileList + (*pFileIndex * MAX_PATH));
+        }
+        
+        // get next entry
+        
+        if (pstrNextName != NULL)
+        {
+            if (*pFileIndex < FileCount - 1)
+                *pFileIndex += 1;
+            else
+                *pFileIndex = 0;
+            
+            strcpy (pstrNextName, pFileList + (*pFileIndex * MAX_PATH));
+        }
+        
+        return TRUE;
+    }
+    else
+    {
+        return FALSE;
+    }
+}
+
+//-----------------
+//  LoadImageFile
+//-----------------
+
+BOOL LoadImageFile (HWND hwnd, PTSTR pstrPathName,
+                png_byte **ppbImage, int *pxImgSize, int *pyImgSize,
+                int *piChannels, png_color *pBkgColor)
+{
+    static TCHAR szTmp [MAX_PATH];
+
+    // if there's an existing PNG, free the memory
+
+    if (*ppbImage)
+    {
+        free (*ppbImage);
+        *ppbImage = NULL;
+    }
+
+    // Load the entire PNG into memory
+
+    SetCursor (LoadCursor (NULL, IDC_WAIT));
+    ShowCursor (TRUE);
+
+    PngLoadImage (pstrPathName, ppbImage, pxImgSize, pyImgSize, piChannels,
+                  pBkgColor);
+
+    ShowCursor (FALSE);
+    SetCursor (LoadCursor (NULL, IDC_ARROW));
+
+    if (*ppbImage != NULL)
+    {
+        sprintf (szTmp, "VisualPng - %s", strrchr(pstrPathName, '\\') + 1);
+        SetWindowText (hwnd, szTmp);
+    }
+    else
+    {
+        MessageBox (hwnd, TEXT ("Error in loading the PNG image"),
+            szProgName, MB_ICONEXCLAMATION | MB_OK);
+        return FALSE;
+    }
+
+    return TRUE;
+}
+
+//----------------
+//  DisplayImage
+//----------------
+
+BOOL DisplayImage (HWND hwnd, BYTE **ppDib,
+        BYTE **ppDiData, int cxWinSize, int cyWinSize,
+        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,
+        BOOL bStretched)
+{
+    BYTE                       *pDib = *ppDib;
+    BYTE                       *pDiData = *ppDiData;
+    // BITMAPFILEHEADER        *pbmfh;
+    BITMAPINFOHEADER           *pbmih;
+    WORD                        wDIRowBytes;
+    png_color                   bkgBlack = {0, 0, 0};
+    png_color                   bkgGray  = {127, 127, 127};
+    png_color                   bkgWhite = {255, 255, 255};
+
+    // allocate memory for the Device Independant bitmap
+
+    wDIRowBytes = (WORD) ((3 * cxWinSize + 3L) >> 2) << 2;
+
+    if (pDib)
+    {
+        free (pDib);
+        pDib = NULL;
+    }
+
+    if (!(pDib = (BYTE *) malloc (sizeof(BITMAPINFOHEADER) +
+        wDIRowBytes * cyWinSize)))
+    {
+        MessageBox (hwnd, TEXT ("Error in displaying the PNG image"),
+            szProgName, MB_ICONEXCLAMATION | MB_OK);
+        *ppDib = pDib = NULL;
+        return FALSE;
+    }
+    *ppDib = pDib;
+    memset (pDib, 0, sizeof(BITMAPINFOHEADER));
+
+    // initialize the dib-structure
+
+    pbmih = (BITMAPINFOHEADER *) pDib;
+    pbmih->biSize = sizeof(BITMAPINFOHEADER);
+    pbmih->biWidth = cxWinSize;
+    pbmih->biHeight = -((long) cyWinSize);
+    pbmih->biPlanes = 1;
+    pbmih->biBitCount = 24;
+    pbmih->biCompression = 0;
+    pDiData = pDib + sizeof(BITMAPINFOHEADER);
+    *ppDiData = pDiData;
+
+    // first fill bitmap with gray and image border
+
+    InitBitmap (pDiData, cxWinSize, cyWinSize);
+
+    // then fill bitmap with image
+
+    if (pbImage)
+    {
+        FillBitmap (
+            pDiData, cxWinSize, cyWinSize,
+            pbImage, cxImgSize, cyImgSize, cImgChannels,
+            bStretched);
+    }
+
+    return TRUE;
+}
+
+//--------------
+//  InitBitmap
+//--------------
+
+BOOL InitBitmap (BYTE *pDiData, int cxWinSize, int cyWinSize)
+{
+    BYTE *dst;
+    int x, y, col;
+
+    // initialize the background with gray
+
+    dst = pDiData;
+    for (y = 0; y < cyWinSize; y++)
+    {
+        col = 0;
+        for (x = 0; x < cxWinSize; x++)
+        {
+            // fill with GRAY
+            *dst++ = 127;
+            *dst++ = 127;
+            *dst++ = 127;
+            col += 3;
+        }
+        // rows start on 4 byte boundaries
+        while ((col % 4) != 0)
+        {
+            dst++;
+            col++;
+        }
+    }
+
+    return TRUE;
+}
+
+//--------------
+//  FillBitmap
+//--------------
+
+BOOL FillBitmap (
+        BYTE *pDiData, int cxWinSize, int cyWinSize,
+        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,
+        BOOL bStretched)
+{
+    BYTE *pStretchedImage;
+    BYTE *pImg;
+    BYTE *src, *dst;
+    BYTE r, g, b, a;
+    const int cDIChannels = 3;
+    WORD wImgRowBytes;
+    WORD wDIRowBytes;
+    int cxNewSize, cyNewSize;
+    int cxImgPos, cyImgPos;
+    int xImg, yImg;
+    int xWin, yWin;
+    int xOld, yOld;
+    int xNew, yNew;
+
+    if (bStretched)
+    {
+        cxNewSize = cxWinSize - 2 * MARGIN;
+        cyNewSize = cyWinSize - 2 * MARGIN;
+
+        // stretch the image to it's window determined size
+
+        // the following two are the same, but the first has side-effects
+        // because of rounding
+//      if ((cyNewSize / cxNewSize) > (cyImgSize / cxImgSize))
+        if ((cyNewSize * cxImgSize) > (cyImgSize * cxNewSize))
+        {
+            cyNewSize = cxNewSize * cyImgSize / cxImgSize;
+            cxImgPos = MARGIN;
+            cyImgPos = (cyWinSize - cyNewSize) / 2;
+        }
+        else
+        {
+            cxNewSize = cyNewSize * cxImgSize / cyImgSize;
+            cyImgPos = MARGIN;
+            cxImgPos = (cxWinSize - cxNewSize) / 2;
+        }
+
+        pStretchedImage = malloc (cImgChannels * cxNewSize * cyNewSize);
+        pImg = pStretchedImage;
+
+        for (yNew = 0; yNew < cyNewSize; yNew++)
+        {
+            yOld = yNew * cyImgSize / cyNewSize;
+            for (xNew = 0; xNew < cxNewSize; xNew++)
+            {
+                xOld = xNew * cxImgSize / cxNewSize;
+
+                r = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld) + 0);
+                g = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld) + 1);
+                b = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld) + 2);
+                *pImg++ = r;
+                *pImg++ = g;
+                *pImg++ = b;
+                if (cImgChannels == 4)
+                {
+                    a = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld)
+                        + 3);
+                    *pImg++ = a;
+                }
+            }
+        }
+
+        // calculate row-bytes
+
+        wImgRowBytes = cImgChannels * cxNewSize;
+        wDIRowBytes = (WORD) ((cDIChannels * cxWinSize + 3L) >> 2) << 2;
+
+        // copy image to screen
+
+        for (yImg = 0, yWin = cyImgPos; yImg < cyNewSize; yImg++, yWin++)
+        {
+            if (yWin >= cyWinSize - cyImgPos)
+                break;
+            src = pStretchedImage + yImg * wImgRowBytes;
+            dst = pDiData + yWin * wDIRowBytes + cxImgPos * cDIChannels;
+
+            for (xImg = 0, xWin = cxImgPos; xImg < cxNewSize; xImg++, xWin++)
+            {
+                if (xWin >= cxWinSize - cxImgPos)
+                    break;
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                *dst++ = b; /* note the reverse order */
+                *dst++ = g;
+                *dst++ = r;
+                if (cImgChannels == 4)
+                {
+                    a = *src++;
+                }
+            }
+        }
+
+        // free memory
+
+        if (pStretchedImage != NULL)
+        {
+            free (pStretchedImage);
+            pStretchedImage = NULL;
+        }
+
+    }
+
+    // process the image not-stretched
+
+    else
+    {
+        // calculate the central position
+
+        cxImgPos = (cxWinSize - cxImgSize) / 2;
+        cyImgPos = (cyWinSize - cyImgSize) / 2;
+
+        // check for image larger than window
+
+        if (cxImgPos < MARGIN)
+            cxImgPos = MARGIN;
+        if (cyImgPos < MARGIN)
+            cyImgPos = MARGIN;
+
+        // calculate both row-bytes
+
+        wImgRowBytes = cImgChannels * cxImgSize;
+        wDIRowBytes = (WORD) ((cDIChannels * cxWinSize + 3L) >> 2) << 2;
+
+        // copy image to screen
+
+        for (yImg = 0, yWin = cyImgPos; yImg < cyImgSize; yImg++, yWin++)
+        {
+            if (yWin >= cyWinSize - MARGIN)
+                break;
+            src = pbImage + yImg * wImgRowBytes;
+            dst = pDiData + yWin * wDIRowBytes + cxImgPos * cDIChannels;
+
+            for (xImg = 0, xWin = cxImgPos; xImg < cxImgSize; xImg++, xWin++)
+            {
+                if (xWin >= cxWinSize - MARGIN)
+                    break;
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                *dst++ = b; /* note the reverse order */
+                *dst++ = g;
+                *dst++ = r;
+                if (cImgChannels == 4)
+                {
+                    a = *src++;
+                }
+            }
+        }
+    }
+
+    return TRUE;
+}
+
+//-----------------
+//  end of source
+//-----------------
diff --git a/gs/libpng/contrib/visupng/VisualPng.dsp b/gs/libpng/contrib/visupng/VisualPng.dsp
new file mode 100644
index 000000000..53ef5a2bc
--- /dev/null
+++ b/gs/libpng/contrib/visupng/VisualPng.dsp
@@ -0,0 +1,147 @@
+# Microsoft Developer Studio Project File - Name="VisualPng" - Package Owner=<4>

+# Microsoft Developer Studio Generated Build File, Format Version 6.00

+# ** DO NOT EDIT **

+

+# TARGTYPE "Win32 (x86) Application" 0x0101

+

+CFG=VisualPng - Win32 Debug

+!MESSAGE This is not a valid makefile. To build this project using NMAKE,

+!MESSAGE use the Export Makefile command and run

+!MESSAGE 

+!MESSAGE NMAKE /f "VisualPng.mak".

+!MESSAGE 

+!MESSAGE You can specify a configuration when running NMAKE

+!MESSAGE by defining the macro CFG on the command line. For example:

+!MESSAGE 

+!MESSAGE NMAKE /f "VisualPng.mak" CFG="VisualPng - Win32 Debug"

+!MESSAGE 

+!MESSAGE Possible choices for configuration are:

+!MESSAGE 

+!MESSAGE "VisualPng - Win32 Release" (based on "Win32 (x86) Application")

+!MESSAGE "VisualPng - Win32 Debug" (based on "Win32 (x86) Application")

+!MESSAGE 

+

+# Begin Project

+# PROP AllowPerConfigDependencies 0

+# PROP Scc_ProjName ""

+# PROP Scc_LocalPath ""

+CPP=cl.exe

+MTL=midl.exe

+RSC=rc.exe

+

+!IF  "$(CFG)" == "VisualPng - Win32 Release"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 0

+# PROP BASE Output_Dir "Release"

+# PROP BASE Intermediate_Dir "Release"

+# PROP BASE Ignore_Export_Lib 0

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 0

+# PROP Output_Dir "Release"

+# PROP Intermediate_Dir "Release"

+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+# ADD BASE CPP /nologo /W3 /O2 /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "NDEBUG" /D "PNG_NO_STDIO" /D "PNG_NO_GLOBAL_ARRAYS" /FD /c

+# SUBTRACT BASE CPP /YX

+# ADD CPP /nologo /MD /W3 /O2 /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "NDEBUG" /D "PNG_NO_STDIO" /D "PNG_NO_GLOBAL_ARRAYS" /FD /c

+# SUBTRACT CPP /YX

+# ADD BASE MTL /nologo /D "NDEBUG" /mktyplib203 /win32

+# ADD MTL /nologo /D "NDEBUG" /mktyplib203 /win32

+# ADD BASE RSC /l 0x409 /d "NDEBUG"

+# ADD RSC /l 0x409 /d "NDEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:windows /machine:I386

+# ADD LINK32 ..\..\projects\visualc6\Win32_LIB_Release\libpng.lib ..\..\..\zlib\projects\visualc6\Win32_LIB_Release\zlib.lib kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:windows /machine:I386

+# Begin Special Build Tool

+OutDir=.\Release

+SOURCE="$(InputPath)"

+PostBuild_Cmds=$(outdir)\VisualPng.exe ..\..\contrib\pngsuite\basn6a16.png

+# End Special Build Tool

+

+!ELSEIF  "$(CFG)" == "VisualPng - Win32 Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

+# PROP BASE Output_Dir "Debug"

+# PROP BASE Intermediate_Dir "Debug"

+# PROP BASE Ignore_Export_Lib 0

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 1

+# PROP Output_Dir "Debug"

+# PROP Intermediate_Dir "Debug"

+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+# ADD BASE CPP /nologo /W3 /Gm /ZI /Od /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "_DEBUG" /D "PNG_NO_STDIO" /D "PNG_NO_GLOBAL_ARRAYS" /FD /GZ /c

+# SUBTRACT BASE CPP /YX

+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "_DEBUG" /D "PNG_NO_STDIO" /D "PNG_NO_GLOBAL_ARRAYS" /FD /GZ /c

+# SUBTRACT CPP /YX

+# ADD BASE MTL /nologo /D "_DEBUG" /mktyplib203 /win32

+# ADD MTL /nologo /D "_DEBUG" /mktyplib203 /win32

+# ADD BASE RSC /l 0x409 /d "_DEBUG"

+# ADD RSC /l 0x409 /d "_DEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:windows /debug /machine:I386 /pdbtype:sept

+# ADD LINK32 ..\..\projects\visualc6\Win32_LIB_Release\libpng.lib ..\..\..\zlib\projects\visualc6\Win32_LIB_Release\zlib.lib kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:windows /debug /machine:I386 /nodefaultlib:"msvcrt.lib" /pdbtype:sept

+# Begin Special Build Tool

+OutDir=.\Debug

+SOURCE="$(InputPath)"

+PostBuild_Cmds=$(outdir)\VisualPng.exe ..\..\contrib\pngsuite\basn6a16.png

+# End Special Build Tool

+

+!ENDIF 

+

+# Begin Target

+

+# Name "VisualPng - Win32 Release"

+# Name "VisualPng - Win32 Debug"

+# Begin Group "Source Files"

+

+# PROP Default_Filter "cpp;c;cxx;rc;def;r;odl;idl;hpj;bat"

+# Begin Source File

+

+SOURCE=.\PngFile.c

+# End Source File

+# Begin Source File

+

+SOURCE=.\VisualPng.c

+# End Source File

+# End Group

+# Begin Group "Header Files"

+

+# PROP Default_Filter "h;hpp;hxx;hm;inl"

+# Begin Source File

+

+SOURCE=.\cexcept.h

+# End Source File

+# Begin Source File

+

+SOURCE=.\PngFile.h

+# End Source File

+# Begin Source File

+

+SOURCE=.\resource.h

+# End Source File

+# End Group

+# Begin Group "Resource Files"

+

+# PROP Default_Filter "ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe"

+# Begin Source File

+

+SOURCE=.\VisualPng.ico

+# End Source File

+# Begin Source File

+

+SOURCE=.\VisualPng.rc

+# End Source File

+# End Group

+# End Target

+# End Project

diff --git a/gs/libpng/contrib/visupng/VisualPng.dsw b/gs/libpng/contrib/visupng/VisualPng.dsw
new file mode 100644
index 000000000..a30e1cc1c
--- /dev/null
+++ b/gs/libpng/contrib/visupng/VisualPng.dsw
@@ -0,0 +1,29 @@
+Microsoft Developer Studio Workspace File, Format Version 6.00

+# WARNING: DO NOT EDIT OR DELETE THIS WORKSPACE FILE!

+

+###############################################################################

+

+Project: "VisualPng"=.\VisualPng.dsp - Package Owner=<4>

+

+Package=<5>

+{{{

+}}}

+

+Package=<4>

+{{{

+}}}

+

+###############################################################################

+

+Global:

+

+Package=<5>

+{{{

+}}}

+

+Package=<3>

+{{{

+}}}

+

+###############################################################################

+

diff --git a/gs/libpng/contrib/visupng/VisualPng.ico b/gs/libpng/contrib/visupng/VisualPng.ico
new file mode 100644
index 000000000..68aa3719f
--- /dev/null
+++ b/gs/libpng/contrib/visupng/VisualPng.ico
diff --git a/gs/libpng/contrib/visupng/VisualPng.png b/gs/libpng/contrib/visupng/VisualPng.png
new file mode 100644
index 000000000..c6aa80a9b
--- /dev/null
+++ b/gs/libpng/contrib/visupng/VisualPng.png
diff --git a/gs/libpng/contrib/visupng/VisualPng.rc b/gs/libpng/contrib/visupng/VisualPng.rc
new file mode 100644
index 000000000..151c68c47
--- /dev/null
+++ b/gs/libpng/contrib/visupng/VisualPng.rc
@@ -0,0 +1,152 @@
+//Microsoft Developer Studio generated resource script.
+//
+#include "resource.h"
+
+#define APSTUDIO_READONLY_SYMBOLS
+/////////////////////////////////////////////////////////////////////////////
+//
+// Generated from the TEXTINCLUDE 2 resource.
+//
+#include "afxres.h"
+
+/////////////////////////////////////////////////////////////////////////////
+#undef APSTUDIO_READONLY_SYMBOLS
+
+/////////////////////////////////////////////////////////////////////////////
+// English (U.S.) resources
+
+#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_ENU)
+#ifdef _WIN32
+LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US
+#pragma code_page(1252)
+#endif //_WIN32
+
+#ifdef APSTUDIO_INVOKED
+/////////////////////////////////////////////////////////////////////////////
+//
+// TEXTINCLUDE
+//
+
+1 TEXTINCLUDE DISCARDABLE 
+BEGIN
+    "resource.h\0"
+END
+
+2 TEXTINCLUDE DISCARDABLE 
+BEGIN
+    "#include ""afxres.h""\r\n"
+    "\0"
+END
+
+3 TEXTINCLUDE DISCARDABLE 
+BEGIN
+    "\r\n"
+    "\0"
+END
+
+#endif    // APSTUDIO_INVOKED
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Menu
+//
+
+VISUALPNG MENU DISCARDABLE 
+BEGIN
+    POPUP "&File"
+    BEGIN
+        MENUITEM "&Open Image...\tCtrl+O",      IDM_FILE_OPEN
+        MENUITEM "Save &As...",                 IDM_FILE_SAVE
+        MENUITEM SEPARATOR
+        MENUITEM "&Next Image\tCtrl+N",         IDM_FILE_NEXT
+        MENUITEM "Pre&vious Image\tCtrl+V",     IDM_FILE_PREVIOUS
+        MENUITEM SEPARATOR
+        MENUITEM "E&xit\tAlt+X",                IDM_FILE_EXIT
+    END
+    POPUP "&Options"
+    BEGIN
+        MENUITEM "&Stretch",                    IDM_OPTIONS_STRETCH, CHECKED
+    END
+    POPUP "&Help"
+    BEGIN
+        MENUITEM "&About",                      IDM_HELP_ABOUT
+    END
+END
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Accelerator
+//
+
+VISUALPNG ACCELERATORS DISCARDABLE 
+BEGIN
+    "N",            IDM_FILE_NEXT,          VIRTKEY, CONTROL, NOINVERT
+    "O",            IDM_FILE_OPEN,          VIRTKEY, CONTROL, NOINVERT
+    "P",            IDM_FILE_PREVIOUS,      VIRTKEY, CONTROL, NOINVERT
+    "V",            IDM_FILE_PREVIOUS,      VIRTKEY, CONTROL, NOINVERT
+    "X",            IDM_FILE_EXIT,          VIRTKEY, ALT, NOINVERT
+END
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Icon
+//
+
+// Icon with lowest ID value placed first to ensure application icon
+// remains consistent on all systems.
+VISUALPNG               ICON    DISCARDABLE     "VisualPng.ico"
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Dialog
+//
+
+ABOUTBOX DIALOG DISCARDABLE  0, 0, 186, 94
+STYLE DS_MODALFRAME | WS_POPUP
+FONT 8, "MS Sans Serif"
+BEGIN
+    DEFPUSHBUTTON   "OK",IDOK,68,67,50,14
+    CTEXT           "VisualPng 1.0  -  June 2000",IDC_STATIC,49,14,88,8
+    LTEXT           "a PNG image viewer",IDC_STATIC,60,30,66,8
+    LTEXT           "(c) Willem van Schaik, 2000",IDC_STATIC,48,52,90,8
+    LTEXT           "to demonstrate the use of libpng in Visual C",
+                    IDC_STATIC,25,38,136,8
+END
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// DESIGNINFO
+//
+
+#ifdef APSTUDIO_INVOKED
+GUIDELINES DESIGNINFO DISCARDABLE 
+BEGIN
+    "ABOUTBOX", DIALOG
+    BEGIN
+        LEFTMARGIN, 7
+        RIGHTMARGIN, 179
+        TOPMARGIN, 7
+        BOTTOMMARGIN, 87
+    END
+END
+#endif    // APSTUDIO_INVOKED
+
+#endif    // English (U.S.) resources
+/////////////////////////////////////////////////////////////////////////////
+
+
+
+#ifndef APSTUDIO_INVOKED
+/////////////////////////////////////////////////////////////////////////////
+//
+// Generated from the TEXTINCLUDE 3 resource.
+//
+
+
+/////////////////////////////////////////////////////////////////////////////
+#endif    // not APSTUDIO_INVOKED
+
diff --git a/gs/libpng/contrib/visupng/cexcept.h b/gs/libpng/contrib/visupng/cexcept.h
new file mode 100644
index 000000000..dbea51ebe
--- /dev/null
+++ b/gs/libpng/contrib/visupng/cexcept.h
@@ -0,0 +1,243 @@
+/*===
+cexcept.h 2.0.0 (2001-Jul-12-Thu)
+Adam M. Costello <amc@cs.berkeley.edu>
+
+An interface for exception-handling in ANSI C (C89 and subsequent ISO
+standards), developed jointly with Cosmin Truta <cosmin@cs.toronto.edu>.
+
+    Copyright (c) 2001 Adam M. Costello and Cosmin Truta.  Everyone
+    is hereby granted permission to do whatever they like with this
+    file, provided that if they modify it they take reasonable steps to
+    avoid confusing or misleading people about the authors, version,
+    and terms of use of the derived file.  The copyright holders make
+    no guarantees regarding this file, and are not responsible for any
+    damage resulting from its use.
+
+Only user-defined exceptions are supported, not "real" exceptions like
+division by zero or memory segmentation violations.
+
+If this interface is used by multiple .c files, they shouldn't include
+this header file directly.  Instead, create a wrapper header file that
+includes this header file and then invokes the define_exception_type
+macro (see below), and let your .c files include that header file.
+
+The interface consists of one type, one well-known name, and six macros.
+
+
+define_exception_type(type_name);
+
+    This macro is used like an external declaration.  It specifies
+    the type of object that gets copied from the exception thrower to
+    the exception catcher.  The type_name can be any type that can be
+    assigned to, that is, a non-constant arithmetic type, struct, union,
+    or pointer.  Examples:
+
+        define_exception_type(int);
+
+        enum exception { out_of_memory, bad_arguments, disk_full };
+        define_exception_type(enum exception);
+
+        struct exception { int code; const char *msg; };
+        define_exception_type(struct exception);
+
+    Because throwing an exception causes the object to be copied (not
+    just once, but twice), programmers may wish to consider size when
+    choosing the exception type.
+
+
+struct exception_context;
+
+    This type may be used after the define_exception_type() macro has
+    been invoked.  A struct exception_context must be known to both
+    the thrower and the catcher.  It is expected that there be one
+    context for each thread that uses exceptions.  It would certainly
+    be dangerous for multiple threads to access the same context.
+    One thread can use multiple contexts, but that is likely to be
+    confusing and not typically useful.  The application can allocate
+    this structure in any way it pleases--automatic, static, or dynamic.
+    The application programmer should pretend not to know the structure
+    members, which are subject to change.
+
+
+struct exception_context *the_exception_context;
+
+    The Try/Catch and Throw statements (described below) implicitly
+    refer to a context, using the name the_exception_context.  It is
+    the application's responsibility to make sure that this name yields
+    the address of a mutable (non-constant) struct exception_context
+    wherever those statements are used.  Subject to that constraint, the
+    application may declare a variable of this name anywhere it likes
+    (inside a function, in a parameter list, or externally), and may
+    use whatever storage class specifiers (static, extern, etc) or type
+    qualifiers (const, volatile, etc) it likes.  Examples:
+
+        static struct exception_context
+          * const the_exception_context = &foo;
+
+        { struct exception_context *the_exception_context = bar; ... }
+
+        int blah(struct exception_context *the_exception_context, ...);
+
+        extern struct exception_context the_exception_context[1];
+
+    The last example illustrates a trick that avoids creating a pointer
+    object separate from the structure object.
+
+    The name could even be a macro, for example:
+
+        struct exception_context ec_array[numthreads];
+        #define the_exception_context (ec_array + thread_id)
+
+    Be aware that the_exception_context is used several times by the
+    Try/Catch/Throw macros, so it shouldn't be expensive or have side
+    effects.  The expansion must be a drop-in replacement for an
+    identifier, so it's safest to put parentheses around it.
+
+
+void init_exception_context(struct exception_context *ec);
+
+    For context structures allocated statically (by an external
+    definition or using the "static" keyword), the implicit
+    initialization to all zeros is sufficient, but contexts allocated
+    by other means must be initialized using this macro before they
+    are used by a Try/Catch statement.  It does no harm to initialize
+    a context more than once (by using this macro on a statically
+    allocated context, or using this macro twice on the same context),
+    but a context must not be re-initialized after it has been used by a
+    Try/Catch statement.
+
+
+Try statement
+Catch (expression) statement
+
+    The Try/Catch/Throw macros are capitalized in order to avoid
+    confusion with the C++ keywords, which have subtly different
+    semantics.
+
+    A Try/Catch statement has a syntax similar to an if/else statement,
+    except that the parenthesized expression goes after the second
+    keyword rather than the first.  As with if/else, there are two
+    clauses, each of which may be a simple statement ending with a
+    semicolon or a brace-enclosed compound statement.  But whereas
+    the else clause is optional, the Catch clause is required.  The
+    expression must be a modifiable lvalue (something capable of being
+    assigned to) of the same type (disregarding type qualifiers) that
+    was passed to define_exception_type().
+
+    If a Throw that uses the same exception context as the Try/Catch is
+    executed within the Try clause (typically within a function called
+    by the Try clause), and the exception is not caught by a nested
+    Try/Catch statement, then a copy of the exception will be assigned
+    to the expression, and control will jump to the Catch clause.  If no
+    such Throw is executed, then the assignment is not performed, and
+    the Catch clause is not executed.
+
+    The expression is not evaluated unless and until the exception is
+    caught, which is significant if it has side effects, for example:
+
+        Try foo();
+        Catch (p[++i].e) { ... }
+
+    IMPORTANT: Jumping into or out of a Try clause (for example via
+    return, break, continue, goto, longjmp) is forbidden--the compiler
+    will not complain, but bad things will happen at run-time.  Jumping
+    into or out of a Catch clause is okay, and so is jumping around
+    inside a Try clause.  In many cases where one is tempted to return
+    from a Try clause, it will suffice to use Throw, and then return
+    from the Catch clause.  Another option is to set a flag variable and
+    use goto to jump to the end of the Try clause, then check the flag
+    after the Try/Catch statement.
+
+    IMPORTANT: The values of any non-volatile automatic variables
+    changed within the Try clause are undefined after an exception is
+    caught.  Therefore, variables modified inside the Try block whose
+    values are needed later outside the Try block must either use static
+    storage or be declared with the "volatile" type qualifier.
+
+
+Throw expression;
+
+    A Throw statement is very much like a return statement, except that
+    the expression is required.  Whereas return jumps back to the place
+    where the current function was called, Throw jumps back to the Catch
+    clause of the innermost enclosing Try clause.  The expression must
+    be compatible with the type passed to define_exception_type().  The
+    exception must be caught, otherwise the program may crash.
+
+    Slight limitation:  If the expression is a comma-expression it must
+    be enclosed in parentheses.
+
+
+Try statement
+Catch_anonymous statement
+
+    When the value of the exception is not needed, a Try/Catch statement
+    can use Catch_anonymous instead of Catch (expression).
+
+
+Everything below this point is for the benefit of the compiler.  The
+application programmer should pretend not to know any of it, because it
+is subject to change.
+
+===*/
+
+
+#ifndef CEXCEPT_H
+#define CEXCEPT_H
+
+
+#include <setjmp.h>
+
+#define define_exception_type(etype) \
+struct exception_context { \
+  jmp_buf *penv; \
+  int caught; \
+  volatile struct { etype etmp; } v; \
+}
+
+/* etmp must be volatile because the application might use automatic */
+/* storage for the_exception_context, and etmp is modified between   */
+/* the calls to setjmp() and longjmp().  A wrapper struct is used to */
+/* avoid warnings about a duplicate volatile qualifier in case etype */
+/* already includes it.                                              */
+
+#define init_exception_context(ec) ((void)((ec)->penv = 0))
+
+#define Try \
+  { \
+    jmp_buf *exception__prev, exception__env; \
+    exception__prev = the_exception_context->penv; \
+    the_exception_context->penv = &exception__env; \
+    if (setjmp(exception__env) == 0) { \
+      if (&exception__prev)
+
+#define exception__catch(action) \
+      else { } \
+      the_exception_context->caught = 0; \
+    } \
+    else { \
+      the_exception_context->caught = 1; \
+    } \
+    the_exception_context->penv = exception__prev; \
+  } \
+  if (!the_exception_context->caught || action) { } \
+  else
+
+#define Catch(e) exception__catch(((e) = the_exception_context->v.etmp, 0))
+#define Catch_anonymous exception__catch(0)
+
+/* Try ends with if(), and Catch begins and ends with else.  This     */
+/* ensures that the Try/Catch syntax is really the same as the        */
+/* if/else syntax.                                                    */
+/*                                                                    */
+/* We use &exception__prev instead of 1 to appease compilers that     */
+/* warn about constant expressions inside if().  Most compilers       */
+/* should still recognize that &exception__prev is never zero and     */
+/* avoid generating test code.                                        */
+
+#define Throw \
+  for (;; longjmp(*the_exception_context->penv, 1)) \
+    the_exception_context->v.etmp =
+
+
+#endif /* CEXCEPT_H */
diff --git a/gs/libpng/contrib/visupng/resource.h b/gs/libpng/contrib/visupng/resource.h
new file mode 100644
index 000000000..611dd035f
--- /dev/null
+++ b/gs/libpng/contrib/visupng/resource.h
@@ -0,0 +1,23 @@
+//{{NO_DEPENDENCIES}}
+// Microsoft Developer Studio generated include file.
+// Used by VisualPng.rc
+//
+#define IDM_FILE_OPEN                   40001
+#define IDM_FILE_SAVE                   40002
+#define IDM_FILE_NEXT                   40003
+#define IDM_FILE_PREVIOUS               40004
+#define IDM_FILE_EXIT                   40005
+#define IDM_OPTIONS_BACKGROUND          40006
+#define IDM_OPTIONS_STRETCH             40007
+#define IDM_HELP_ABOUT                  40008
+
+// Next default values for new objects
+// 
+#ifdef APSTUDIO_INVOKED
+#ifndef APSTUDIO_READONLY_SYMBOLS
+#define _APS_NEXT_RESOURCE_VALUE        113
+#define _APS_NEXT_COMMAND_VALUE         40009
+#define _APS_NEXT_CONTROL_VALUE         1001
+#define _APS_NEXT_SYMED_VALUE           101
+#endif
+#endif
diff --git a/gs/libpng/example.c b/gs/libpng/example.c
new file mode 100644
index 000000000..ba0ecc5b5
--- /dev/null
+++ b/gs/libpng/example.c
@@ -0,0 +1,808 @@
+
+#if 0 /* in case someone actually tries to compile this */
+
+/* example.c - an example of using libpng */
+
+/* This is an example of how to use libpng to read and write PNG files.
+ * The file libpng.txt is much more verbose then this.  If you have not
+ * read it, do so first.  This was designed to be a starting point of an
+ * implementation.  This is not officially part of libpng, is hereby placed
+ * in the public domain, and therefore does not require a copyright notice.
+ *
+ * This file does not currently compile, because it is missing certain
+ * parts, like allocating memory to hold an image.  You will have to
+ * supply these parts to get it to compile.  For an example of a minimal
+ * working PNG reader/writer, see pngtest.c, included in this distribution;
+ * see also the programs in the contrib directory.
+ */
+
+#include "png.h"
+
+ /* The png_jmpbuf() macro, used in error handling, became available in
+  * libpng version 1.0.6.  If you want to be able to run your code with older
+  * versions of libpng, you must define the macro yourself (but only if it
+  * is not already defined by libpng!).
+  */
+
+#ifndef png_jmpbuf
+#  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
+#endif
+
+/* Check to see if a file is a PNG file using png_sig_cmp().  png_sig_cmp()
+ * returns zero if the image is a PNG and nonzero if it isn't a PNG.
+ *
+ * The function check_if_png() shown here, but not used, returns nonzero (true)
+ * if the file can be opened and is a PNG, 0 (false) otherwise.
+ *
+ * If this call is successful, and you are going to keep the file open,
+ * you should call png_set_sig_bytes(png_ptr, PNG_BYTES_TO_CHECK); once
+ * you have created the png_ptr, so that libpng knows your application
+ * has read that many bytes from the start of the file.  Make sure you
+ * don't call png_set_sig_bytes() with more than 8 bytes read or give it
+ * an incorrect number of bytes read, or you will either have read too
+ * many bytes (your fault), or you are telling libpng to read the wrong
+ * number of magic bytes (also your fault).
+ *
+ * Many applications already read the first 2 or 4 bytes from the start
+ * of the image to determine the file type, so it would be easiest just
+ * to pass the bytes to png_sig_cmp() or even skip that if you know
+ * you have a PNG file, and call png_set_sig_bytes().
+ */
+#define PNG_BYTES_TO_CHECK 4
+int check_if_png(char *file_name, FILE **fp)
+{
+   char buf[PNG_BYTES_TO_CHECK];
+
+   /* Open the prospective PNG file. */
+   if ((*fp = fopen(file_name, "rb")) == NULL)
+      return 0;
+
+   /* Read in some of the signature bytes */
+   if (fread(buf, 1, PNG_BYTES_TO_CHECK, *fp) != PNG_BYTES_TO_CHECK)
+      return 0;
+
+   /* Compare the first PNG_BYTES_TO_CHECK bytes of the signature.
+      Return nonzero (true) if they match */
+
+   return(!png_sig_cmp(buf, (png_size_t)0, PNG_BYTES_TO_CHECK));
+}
+
+/* Read a PNG file.  You may want to return an error code if the read
+ * fails (depending upon the failure).  There are two "prototypes" given
+ * here - one where we are given the filename, and we need to open the
+ * file, and the other where we are given an open file (possibly with
+ * some or all of the magic bytes read - see comments above).
+ */
+#ifdef open_file /* prototype 1 */
+void read_png(char *file_name)  /* We need to open the file */
+{
+   png_structp png_ptr;
+   png_infop info_ptr;
+   unsigned int sig_read = 0;
+   png_uint_32 width, height;
+   int bit_depth, color_type, interlace_type;
+   FILE *fp;
+
+   if ((fp = fopen(file_name, "rb")) == NULL)
+      return (ERROR);
+#else no_open_file /* prototype 2 */
+void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
+{
+   png_structp png_ptr;
+   png_infop info_ptr;
+   png_uint_32 width, height;
+   int bit_depth, color_type, interlace_type;
+#endif no_open_file /* only use one prototype! */
+
+   /* Create and initialize the png_struct with the desired error handler
+    * functions.  If you want to use the default stderr and longjump method,
+    * you can supply NULL for the last three parameters.  We also supply the
+    * the compiler header file version, so that we know if the application
+    * was compiled with a compatible version of the library.  REQUIRED
+    */
+   png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
+      png_voidp user_error_ptr, user_error_fn, user_warning_fn);
+
+   if (png_ptr == NULL)
+   {
+      fclose(fp);
+      return (ERROR);
+   }
+
+   /* Allocate/initialize the memory for image information.  REQUIRED. */
+   info_ptr = png_create_info_struct(png_ptr);
+   if (info_ptr == NULL)
+   {
+      fclose(fp);
+      png_destroy_read_struct(&png_ptr, png_infopp_NULL, png_infopp_NULL);
+      return (ERROR);
+   }
+
+   /* Set error handling if you are using the setjmp/longjmp method (this is
+    * the normal method of doing things with libpng).  REQUIRED unless you
+    * set up your own error handlers in the png_create_read_struct() earlier.
+    */
+
+   if (setjmp(png_jmpbuf(png_ptr)))
+   {
+      /* Free all of the memory associated with the png_ptr and info_ptr */
+      png_destroy_read_struct(&png_ptr, &info_ptr, png_infopp_NULL);
+      fclose(fp);
+      /* If we get here, we had a problem reading the file */
+      return (ERROR);
+   }
+
+   /* One of the following I/O initialization methods is REQUIRED */
+#ifdef streams /* PNG file I/O method 1 */
+   /* Set up the input control if you are using standard C streams */
+   png_init_io(png_ptr, fp);
+
+#else no_streams /* PNG file I/O method 2 */
+   /* If you are using replacement read functions, instead of calling
+    * png_init_io() here you would call:
+    */
+   png_set_read_fn(png_ptr, (void *)user_io_ptr, user_read_fn);
+   /* where user_io_ptr is a structure you want available to the callbacks */
+#endif no_streams /* Use only one I/O method! */
+
+   /* If we have already read some of the signature */
+   png_set_sig_bytes(png_ptr, sig_read);
+
+#ifdef hilevel
+   /*
+    * If you have enough memory to read in the entire image at once,
+    * and you need to specify only transforms that can be controlled
+    * with one of the PNG_TRANSFORM_* bits (this presently excludes
+    * dithering, filling, setting background, and doing gamma
+    * adjustment), then you can read the entire image (including
+    * pixels) into the info structure with this call:
+    */
+   png_read_png(png_ptr, info_ptr, png_transforms, png_voidp_NULL);
+#else
+   /* OK, you're doing it the hard way, with the lower-level functions */
+
+   /* The call to png_read_info() gives us all of the information from the
+    * PNG file before the first IDAT (image data chunk).  REQUIRED
+    */
+   png_read_info(png_ptr, info_ptr);
+
+   png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+       &interlace_type, int_p_NULL, int_p_NULL);
+
+/* Set up the data transformations you want.  Note that these are all
+ * optional.  Only call them if you want/need them.  Many of the
+ * transformations only work on specific types of images, and many
+ * are mutually exclusive.
+ */
+
+   /* tell libpng to strip 16 bit/color files down to 8 bits/color */
+   png_set_strip_16(png_ptr);
+
+   /* Strip alpha bytes from the input data without combining with the
+    * background (not recommended).
+    */
+   png_set_strip_alpha(png_ptr);
+
+   /* Extract multiple pixels with bit depths of 1, 2, and 4 from a single
+    * byte into separate bytes (useful for paletted and grayscale images).
+    */
+   png_set_packing(png_ptr);
+
+   /* Change the order of packed pixels to least significant bit first
+    * (not useful if you are using png_set_packing). */
+   png_set_packswap(png_ptr);
+
+   /* Expand paletted colors into true RGB triplets */
+   if (color_type == PNG_COLOR_TYPE_PALETTE)
+      png_set_palette_rgb(png_ptr);
+
+   /* Expand grayscale images to the full 8 bits from 1, 2, or 4 bits/pixel */
+   if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+      png_set_gray_1_2_4_to_8(png_ptr);
+
+   /* Expand paletted or RGB images with transparency to full alpha channels
+    * so the data will be available as RGBA quartets.
+    */
+   if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+      png_set_tRNS_to_alpha(png_ptr);
+
+   /* Set the background color to draw transparent and alpha images over.
+    * It is possible to set the red, green, and blue components directly
+    * for paletted images instead of supplying a palette index.  Note that
+    * even if the PNG file supplies a background, you are not required to
+    * use it - you should use the (solid) application background if it has one.
+    */
+
+   png_color_16 my_background, *image_background;
+
+   if (png_get_bKGD(png_ptr, info_ptr, &image_background))
+      png_set_background(png_ptr, image_background,
+                         PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
+   else
+      png_set_background(png_ptr, &my_background,
+                         PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
+
+   /* Some suggestions as to how to get a screen gamma value */
+
+   /* Note that screen gamma is the display_exponent, which includes
+    * the CRT_exponent and any correction for viewing conditions */
+   if (/* We have a user-defined screen gamma value */)
+   {
+      screen_gamma = user-defined screen_gamma;
+   }
+   /* This is one way that applications share the same screen gamma value */
+   else if ((gamma_str = getenv("SCREEN_GAMMA")) != NULL)
+   {
+      screen_gamma = atof(gamma_str);
+   }
+   /* If we don't have another value */
+   else
+   {
+      screen_gamma = 2.2;  /* A good guess for a PC monitors in a dimly
+                              lit room */
+      screen_gamma = 1.7 or 1.0;  /* A good guess for Mac systems */
+   }
+
+   /* Tell libpng to handle the gamma conversion for you.  The final call
+    * is a good guess for PC generated images, but it should be configurable
+    * by the user at run time by the user.  It is strongly suggested that
+    * your application support gamma correction.
+    */
+
+   int intent;
+
+   if (png_get_sRGB(png_ptr, info_ptr, &intent))
+      png_set_gamma(png_ptr, screen_gamma, 0.45455);
+   else
+   {
+      double image_gamma;
+      if (png_get_gAMA(png_ptr, info_ptr, &image_gamma))
+         png_set_gamma(png_ptr, screen_gamma, image_gamma);
+      else
+         png_set_gamma(png_ptr, screen_gamma, 0.45455);
+   }
+
+   /* Dither RGB files down to 8 bit palette or reduce palettes
+    * to the number of colors available on your screen.
+    */
+   if (color_type & PNG_COLOR_MASK_COLOR)
+   {
+      int num_palette;
+      png_colorp palette;
+
+      /* This reduces the image to the application supplied palette */
+      if (/* we have our own palette */)
+      {
+         /* An array of colors to which the image should be dithered */
+         png_color std_color_cube[MAX_SCREEN_COLORS];
+
+         png_set_dither(png_ptr, std_color_cube, MAX_SCREEN_COLORS,
+            MAX_SCREEN_COLORS, png_uint_16p_NULL, 0);
+      }
+      /* This reduces the image to the palette supplied in the file */
+      else if (png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette))
+      {
+         png_uint_16p histogram = NULL;
+
+         png_get_hIST(png_ptr, info_ptr, &histogram);
+
+         png_set_dither(png_ptr, palette, num_palette,
+                        max_screen_colors, histogram, 0);
+      }
+   }
+
+   /* invert monochrome files to have 0 as white and 1 as black */
+   png_set_invert_mono(png_ptr);
+
+   /* If you want to shift the pixel values from the range [0,255] or
+    * [0,65535] to the original [0,7] or [0,31], or whatever range the
+    * colors were originally in:
+    */
+   if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
+   {
+      png_color_8p sig_bit;
+
+      png_get_sBIT(png_ptr, info_ptr, &sig_bit);
+      png_set_shift(png_ptr, sig_bit);
+   }
+
+   /* flip the RGB pixels to BGR (or RGBA to BGRA) */
+   if (color_type & PNG_COLOR_MASK_COLOR)
+      png_set_bgr(png_ptr);
+
+   /* swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) */
+   png_set_swap_alpha(png_ptr);
+
+   /* swap bytes of 16 bit files to least significant byte first */
+   png_set_swap(png_ptr);
+
+   /* Add filler (or alpha) byte (before/after each RGB triplet) */
+   png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
+
+   /* Turn on interlace handling.  REQUIRED if you are not using
+    * png_read_image().  To see how to handle interlacing passes,
+    * see the png_read_row() method below:
+    */
+   number_passes = png_set_interlace_handling(png_ptr);
+
+   /* Optional call to gamma correct and add the background to the palette
+    * and update info structure.  REQUIRED if you are expecting libpng to
+    * update the palette for you (ie you selected such a transform above).
+    */
+   png_read_update_info(png_ptr, info_ptr);
+
+   /* Allocate the memory to hold the image using the fields of info_ptr. */
+
+   /* The easiest way to read the image: */
+   png_bytep row_pointers[height];
+
+   for (row = 0; row < height; row++)
+   {
+      row_pointers[row] = png_malloc(png_ptr, png_get_rowbytes(png_ptr,
+         info_ptr));
+   }
+
+   /* Now it's time to read the image.  One of these methods is REQUIRED */
+#ifdef entire /* Read the entire image in one go */
+   png_read_image(png_ptr, row_pointers);
+
+#else no_entire /* Read the image one or more scanlines at a time */
+   /* The other way to read images - deal with interlacing: */
+
+   for (pass = 0; pass < number_passes; pass++)
+   {
+#ifdef single /* Read the image a single row at a time */
+      for (y = 0; y < height; y++)
+      {
+         png_read_rows(png_ptr, &row_pointers[y], png_bytepp_NULL, 1);
+      }
+
+#else no_single /* Read the image several rows at a time */
+      for (y = 0; y < height; y += number_of_rows)
+      {
+#ifdef sparkle /* Read the image using the "sparkle" effect. */
+         png_read_rows(png_ptr, &row_pointers[y], png_bytepp_NULL,
+            number_of_rows);
+#else no_sparkle /* Read the image using the "rectangle" effect */
+         png_read_rows(png_ptr, png_bytepp_NULL, &row_pointers[y],
+            number_of_rows);
+#endif no_sparkle /* use only one of these two methods */
+      }
+
+      /* if you want to display the image after every pass, do
+         so here */
+#endif no_single /* use only one of these two methods */
+   }
+#endif no_entire /* use only one of these two methods */
+
+   /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
+   png_read_end(png_ptr, info_ptr);
+#endif hilevel
+
+   /* At this point you have read the entire image */
+
+   /* clean up after the read, and free any memory allocated - REQUIRED */
+   png_destroy_read_struct(&png_ptr, &info_ptr, png_infopp_NULL);
+
+   /* close the file */
+   fclose(fp);
+
+   /* that's it */
+   return (OK);
+}
+
+/* progressively read a file */
+
+int
+initialize_png_reader(png_structp *png_ptr, png_infop *info_ptr)
+{
+   /* Create and initialize the png_struct with the desired error handler
+    * functions.  If you want to use the default stderr and longjump method,
+    * you can supply NULL for the last three parameters.  We also check that
+    * the library version is compatible in case we are using dynamically
+    * linked libraries.
+    */
+   *png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
+       png_voidp user_error_ptr, user_error_fn, user_warning_fn);
+
+   if (*png_ptr == NULL)
+   {
+      *info_ptr = NULL;
+      return (ERROR);
+   }
+
+   *info_ptr = png_create_info_struct(png_ptr);
+
+   if (*info_ptr == NULL)
+   {
+      png_destroy_read_struct(png_ptr, info_ptr, png_infopp_NULL);
+      return (ERROR);
+   }
+
+   if (setjmp(png_jmpbuf((*png_ptr))))
+   {
+      png_destroy_read_struct(png_ptr, info_ptr, png_infopp_NULL);
+      return (ERROR);
+   }
+
+   /* This one's new.  You will need to provide all three
+    * function callbacks, even if you aren't using them all.
+    * If you aren't using all functions, you can specify NULL
+    * parameters.  Even when all three functions are NULL,
+    * you need to call png_set_progressive_read_fn().
+    * These functions shouldn't be dependent on global or
+    * static variables if you are decoding several images
+    * simultaneously.  You should store stream specific data
+    * in a separate struct, given as the second parameter,
+    * and retrieve the pointer from inside the callbacks using
+    * the function png_get_progressive_ptr(png_ptr).
+    */
+   png_set_progressive_read_fn(*png_ptr, (void *)stream_data,
+      info_callback, row_callback, end_callback);
+
+   return (OK);
+}
+
+int
+process_data(png_structp *png_ptr, png_infop *info_ptr,
+   png_bytep buffer, png_uint_32 length)
+{
+   if (setjmp(png_jmpbuf((*png_ptr))))
+   {
+      /* Free the png_ptr and info_ptr memory on error */
+      png_destroy_read_struct(png_ptr, info_ptr, png_infopp_NULL);
+      return (ERROR);
+   }
+
+   /* This one's new also.  Simply give it chunks of data as
+    * they arrive from the data stream (in order, of course).
+    * On Segmented machines, don't give it any more than 64K.
+    * The library seems to run fine with sizes of 4K, although
+    * you can give it much less if necessary (I assume you can
+    * give it chunks of 1 byte, but I haven't tried with less
+    * than 256 bytes yet).  When this function returns, you may
+    * want to display any rows that were generated in the row
+    * callback, if you aren't already displaying them there.
+    */
+   png_process_data(*png_ptr, *info_ptr, buffer, length);
+   return (OK);
+}
+
+info_callback(png_structp png_ptr, png_infop info)
+{
+/* do any setup here, including setting any of the transformations
+ * mentioned in the Reading PNG files section.  For now, you _must_
+ * call either png_start_read_image() or png_read_update_info()
+ * after all the transformations are set (even if you don't set
+ * any).  You may start getting rows before png_process_data()
+ * returns, so this is your last chance to prepare for that.
+ */
+}
+
+row_callback(png_structp png_ptr, png_bytep new_row,
+   png_uint_32 row_num, int pass)
+{
+/*
+ * This function is called for every row in the image.  If the
+ * image is interlaced, and you turned on the interlace handler,
+ * this function will be called for every row in every pass.
+ *
+ * In this function you will receive a pointer to new row data from
+ * libpng called new_row that is to replace a corresponding row (of
+ * the same data format) in a buffer allocated by your application.
+ * 
+ * The new row data pointer new_row may be NULL, indicating there is
+ * no new data to be replaced (in cases of interlace loading).
+ * 
+ * If new_row is not NULL then you need to call
+ * png_progressive_combine_row() to replace the corresponding row as
+ * shown below:
+ */
+   /* Check if row_num is in bounds. */
+   if((row_num >= 0) && (row_num < height))
+   {
+     /* Get pointer to corresponding row in our
+      * PNG read buffer.
+      */
+     png_bytep old_row = ((png_bytep *)our_data)[row_num];
+
+     /* If both rows are allocated then copy the new row
+      * data to the corresponding row data.
+      */
+     if((old_row != NULL) && (new_row != NULL))
+     png_progressive_combine_row(png_ptr, old_row, new_row);
+   }
+/*
+ * The rows and passes are called in order, so you don't really
+ * need the row_num and pass, but I'm supplying them because it
+ * may make your life easier.
+ *
+ * For the non-NULL rows of interlaced images, you must call
+ * png_progressive_combine_row() passing in the new row and the
+ * old row, as demonstrated above.  You can call this function for
+ * NULL rows (it will just return) and for non-interlaced images
+ * (it just does the png_memcpy for you) if it will make the code
+ * easier.  Thus, you can just do this for all cases:
+ */
+
+   png_progressive_combine_row(png_ptr, old_row, new_row);
+
+/* where old_row is what was displayed for previous rows.  Note
+ * that the first pass (pass == 0 really) will completely cover
+ * the old row, so the rows do not have to be initialized.  After
+ * the first pass (and only for interlaced images), you will have
+ * to pass the current row as new_row, and the function will combine
+ * the old row and the new row.
+ */
+}
+
+end_callback(png_structp png_ptr, png_infop info)
+{
+/* this function is called when the whole image has been read,
+ * including any chunks after the image (up to and including
+ * the IEND).  You will usually have the same info chunk as you
+ * had in the header, although some data may have been added
+ * to the comments and time fields.
+ *
+ * Most people won't do much here, perhaps setting a flag that
+ * marks the image as finished.
+ */
+}
+
+/* write a png file */
+void write_png(char *file_name /* , ... other image information ... */)
+{
+   FILE *fp;
+   png_structp png_ptr;
+   png_infop info_ptr;
+   png_colorp palette;
+
+   /* open the file */
+   fp = fopen(file_name, "wb");
+   if (fp == NULL)
+      return (ERROR);
+
+   /* Create and initialize the png_struct with the desired error handler
+    * functions.  If you want to use the default stderr and longjump method,
+    * you can supply NULL for the last three parameters.  We also check that
+    * the library version is compatible with the one used at compile time,
+    * in case we are using dynamically linked libraries.  REQUIRED.
+    */
+   png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
+      png_voidp user_error_ptr, user_error_fn, user_warning_fn);
+
+   if (png_ptr == NULL)
+   {
+      fclose(fp);
+      return (ERROR);
+   }
+
+   /* Allocate/initialize the image information data.  REQUIRED */
+   info_ptr = png_create_info_struct(png_ptr);
+   if (info_ptr == NULL)
+   {
+      fclose(fp);
+      png_destroy_write_struct(&png_ptr,  png_infopp_NULL);
+      return (ERROR);
+   }
+
+   /* Set error handling.  REQUIRED if you aren't supplying your own
+    * error handling functions in the png_create_write_struct() call.
+    */
+   if (setjmp(png_jmpbuf(png_ptr)))
+   {
+      /* If we get here, we had a problem reading the file */
+      fclose(fp);
+      png_destroy_write_struct(&png_ptr, &info_ptr);
+      return (ERROR);
+   }
+
+   /* One of the following I/O initialization functions is REQUIRED */
+#ifdef streams /* I/O initialization method 1 */
+   /* set up the output control if you are using standard C streams */
+   png_init_io(png_ptr, fp);
+#else no_streams /* I/O initialization method 2 */
+   /* If you are using replacement read functions, instead of calling
+    * png_init_io() here you would call */
+   png_set_write_fn(png_ptr, (void *)user_io_ptr, user_write_fn,
+      user_IO_flush_function);
+   /* where user_io_ptr is a structure you want available to the callbacks */
+#endif no_streams /* only use one initialization method */
+
+#ifdef hilevel
+   /* This is the easy way.  Use it if you already have all the
+    * image info living info in the structure.  You could "|" many
+    * PNG_TRANSFORM flags into the png_transforms integer here.
+    */
+   png_write_png(png_ptr, info_ptr, png_transforms, png_voidp_NULL);
+#else
+   /* This is the hard way */
+
+   /* Set the image information here.  Width and height are up to 2^31,
+    * bit_depth is one of 1, 2, 4, 8, or 16, but valid values also depend on
+    * the color_type selected. color_type is one of PNG_COLOR_TYPE_GRAY,
+    * PNG_COLOR_TYPE_GRAY_ALPHA, PNG_COLOR_TYPE_PALETTE, PNG_COLOR_TYPE_RGB,
+    * or PNG_COLOR_TYPE_RGB_ALPHA.  interlace is either PNG_INTERLACE_NONE or
+    * PNG_INTERLACE_ADAM7, and the compression_type and filter_type MUST
+    * currently be PNG_COMPRESSION_TYPE_BASE and PNG_FILTER_TYPE_BASE. REQUIRED
+    */
+   png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth, PNG_COLOR_TYPE_???,
+      PNG_INTERLACE_????, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+   /* set the palette if there is one.  REQUIRED for indexed-color images */
+   palette = (png_colorp)png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH
+             * png_sizeof (png_color));
+   /* ... set palette colors ... */
+   png_set_PLTE(png_ptr, info_ptr, palette, PNG_MAX_PALETTE_LENGTH);
+   /* You must not free palette here, because png_set_PLTE only makes a link to
+      the palette that you malloced.  Wait until you are about to destroy
+      the png structure. */
+
+   /* optional significant bit chunk */
+   /* if we are dealing with a grayscale image then */
+   sig_bit.gray = true_bit_depth;
+   /* otherwise, if we are dealing with a color image then */
+   sig_bit.red = true_red_bit_depth;
+   sig_bit.green = true_green_bit_depth;
+   sig_bit.blue = true_blue_bit_depth;
+   /* if the image has an alpha channel then */
+   sig_bit.alpha = true_alpha_bit_depth;
+   png_set_sBIT(png_ptr, info_ptr, sig_bit);
+
+
+   /* Optional gamma chunk is strongly suggested if you have any guess
+    * as to the correct gamma of the image.
+    */
+   png_set_gAMA(png_ptr, info_ptr, gamma);
+
+   /* Optionally write comments into the image */
+   text_ptr[0].key = "Title";
+   text_ptr[0].text = "Mona Lisa";
+   text_ptr[0].compression = PNG_TEXT_COMPRESSION_NONE;
+   text_ptr[1].key = "Author";
+   text_ptr[1].text = "Leonardo DaVinci";
+   text_ptr[1].compression = PNG_TEXT_COMPRESSION_NONE;
+   text_ptr[2].key = "Description";
+   text_ptr[2].text = "<long text>";
+   text_ptr[2].compression = PNG_TEXT_COMPRESSION_zTXt;
+#ifdef PNG_iTXt_SUPPORTED
+   text_ptr[0].lang = NULL;
+   text_ptr[1].lang = NULL;
+   text_ptr[2].lang = NULL;
+#endif
+   png_set_text(png_ptr, info_ptr, text_ptr, 3);
+
+   /* other optional chunks like cHRM, bKGD, tRNS, tIME, oFFs, pHYs, */
+   /* note that if sRGB is present the gAMA and cHRM chunks must be ignored
+    * on read and must be written in accordance with the sRGB profile */
+
+   /* Write the file header information.  REQUIRED */
+   png_write_info(png_ptr, info_ptr);
+
+   /* If you want, you can write the info in two steps, in case you need to
+    * write your private chunk ahead of PLTE:
+    *
+    *   png_write_info_before_PLTE(write_ptr, write_info_ptr);
+    *   write_my_chunk();
+    *   png_write_info(png_ptr, info_ptr);
+    *
+    * However, given the level of known- and unknown-chunk support in 1.1.0
+    * and up, this should no longer be necessary.
+    */
+
+   /* Once we write out the header, the compression type on the text
+    * chunks gets changed to PNG_TEXT_COMPRESSION_NONE_WR or
+    * PNG_TEXT_COMPRESSION_zTXt_WR, so it doesn't get written out again
+    * at the end.
+    */
+
+   /* set up the transformations you want.  Note that these are
+    * all optional.  Only call them if you want them.
+    */
+
+   /* invert monochrome pixels */
+   png_set_invert_mono(png_ptr);
+
+   /* Shift the pixels up to a legal bit depth and fill in
+    * as appropriate to correctly scale the image.
+    */
+   png_set_shift(png_ptr, &sig_bit);
+
+   /* pack pixels into bytes */
+   png_set_packing(png_ptr);
+
+   /* swap location of alpha bytes from ARGB to RGBA */
+   png_set_swap_alpha(png_ptr);
+
+   /* Get rid of filler (OR ALPHA) bytes, pack XRGB/RGBX/ARGB/RGBA into
+    * RGB (4 channels -> 3 channels). The second parameter is not used.
+    */
+   png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
+
+   /* flip BGR pixels to RGB */
+   png_set_bgr(png_ptr);
+
+   /* swap bytes of 16-bit files to most significant byte first */
+   png_set_swap(png_ptr);
+
+   /* swap bits of 1, 2, 4 bit packed pixel formats */
+   png_set_packswap(png_ptr);
+
+   /* turn on interlace handling if you are not using png_write_image() */
+   if (interlacing)
+      number_passes = png_set_interlace_handling(png_ptr);
+   else
+      number_passes = 1;
+
+   /* The easiest way to write the image (you may have a different memory
+    * layout, however, so choose what fits your needs best).  You need to
+    * use the first method if you aren't handling interlacing yourself.
+    */
+   png_uint_32 k, height, width;
+   png_byte image[height][width*bytes_per_pixel];
+   png_bytep row_pointers[height];
+
+   if (height > PNG_UINT_32_MAX/png_sizeof(png_bytep))
+     png_error (png_ptr, "Image is too tall to process in memory");
+
+   for (k = 0; k < height; k++)
+     row_pointers[k] = image + k*width*bytes_per_pixel;
+
+   /* One of the following output methods is REQUIRED */
+#ifdef entire /* write out the entire image data in one call */
+   png_write_image(png_ptr, row_pointers);
+
+   /* the other way to write the image - deal with interlacing */
+
+#else no_entire /* write out the image data by one or more scanlines */
+   /* The number of passes is either 1 for non-interlaced images,
+    * or 7 for interlaced images.
+    */
+   for (pass = 0; pass < number_passes; pass++)
+   {
+      /* Write a few rows at a time. */
+      png_write_rows(png_ptr, &row_pointers[first_row], number_of_rows);
+
+      /* If you are only writing one row at a time, this works */
+      for (y = 0; y < height; y++)
+      {
+         png_write_rows(png_ptr, &row_pointers[y], 1);
+      }
+   }
+#endif no_entire /* use only one output method */
+
+   /* You can write optional chunks like tEXt, zTXt, and tIME at the end
+    * as well.  Shouldn't be necessary in 1.1.0 and up as all the public
+    * chunks are supported and you can use png_set_unknown_chunks() to
+    * register unknown chunks into the info structure to be written out.
+    */
+
+   /* It is REQUIRED to call this to finish writing the rest of the file */
+   png_write_end(png_ptr, info_ptr);
+#endif hilevel
+
+   /* If you png_malloced a palette, free it here (don't free info_ptr->palette,
+      as recommended in versions 1.0.5m and earlier of this example; if
+      libpng mallocs info_ptr->palette, libpng will free it).  If you
+      allocated it with malloc() instead of png_malloc(), use free() instead
+      of png_free(). */
+   png_free(png_ptr, palette);
+   palette=NULL;
+
+   /* Similarly, if you png_malloced any data that you passed in with
+      png_set_something(), such as a hist or trans array, free it here,
+      when you can be sure that libpng is through with it. */
+   png_free(png_ptr, trans);
+   trans=NULL;
+
+   /* clean up after the write, and free any memory allocated */
+   png_destroy_write_struct(&png_ptr, &info_ptr);
+
+   /* close the file */
+   fclose(fp);
+
+   /* that's it */
+   return (OK);
+}
+
+#endif /* if 0 */
diff --git a/gs/libpng/libpng.3 b/gs/libpng/libpng.3
new file mode 100644
index 000000000..1feceee38
--- /dev/null
+++ b/gs/libpng/libpng.3
@@ -0,0 +1,4022 @@
+.TH LIBPNG 3 "December 3, 2004"
+.SH NAME
+libpng \- Portable Network Graphics (PNG) Reference Library 1.2.8
+.SH SYNOPSIS
+\fI\fB
+
+\fB#include <png.h>\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_access_version_number \fI(void\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_check_sig (png_bytep \fP\fIsig\fP\fB, int \fInum\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_chunk_error (png_structp \fP\fIpng_ptr\fP\fB, png_const_charp \fIerror\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_chunk_warning (png_structp \fP\fIpng_ptr\fP\fB, png_const_charp \fImessage\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_convert_from_struct_tm (png_timep \fP\fIptime\fP\fB, struct tm FAR * \fIttime\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_convert_from_time_t (png_timep \fP\fIptime\fP\fB, time_t \fIttime\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_charp png_convert_to_rfc1123 (png_structp \fP\fIpng_ptr\fP\fB, png_timep \fIptime\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_infop png_create_info_struct (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_structp png_create_read_struct (png_const_charp \fP\fIuser_png_ver\fP\fB, png_voidp \fP\fIerror_ptr\fP\fB, png_error_ptr \fP\fIerror_fn\fP\fB, png_error_ptr \fIwarn_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_structp png_create_read_struct_2(png_const_charp \fP\fIuser_png_ver\fP\fB, png_voidp \fP\fIerror_ptr\fP\fB, png_error_ptr \fP\fIerror_fn\fP\fB, png_error_ptr \fP\fIwarn_fn\fP\fB, png_voidp \fP\fImem_ptr\fP\fB, png_malloc_ptr \fP\fImalloc_fn\fP\fB, png_free_ptr \fIfree_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_structp png_create_write_struct (png_const_charp \fP\fIuser_png_ver\fP\fB, png_voidp \fP\fIerror_ptr\fP\fB, png_error_ptr \fP\fIerror_fn\fP\fB, png_error_ptr \fIwarn_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_structp png_create_write_struct_2(png_const_charp \fP\fIuser_png_ver\fP\fB, png_voidp \fP\fIerror_ptr\fP\fB, png_error_ptr \fP\fIerror_fn\fP\fB, png_error_ptr \fP\fIwarn_fn\fP\fB, png_voidp \fP\fImem_ptr\fP\fB, png_malloc_ptr \fP\fImalloc_fn\fP\fB, png_free_ptr \fIfree_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_debug(int \fP\fIlevel\fP\fB, png_const_charp \fImessage\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_debug1(int \fP\fIlevel\fP\fB, png_const_charp \fP\fImessage\fP\fB, \fIp1\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_debug2(int \fP\fIlevel\fP\fB, png_const_charp \fP\fImessage\fP\fB, \fP\fIp1\fP\fB, \fIp2\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_destroy_info_struct (png_structp \fP\fIpng_ptr\fP\fB, png_infopp \fIinfo_ptr_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_destroy_read_struct (png_structpp \fP\fIpng_ptr_ptr\fP\fB, png_infopp \fP\fIinfo_ptr_ptr\fP\fB, png_infopp \fIend_info_ptr_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_destroy_write_struct (png_structpp \fP\fIpng_ptr_ptr\fP\fB, png_infopp \fIinfo_ptr_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_error (png_structp \fP\fIpng_ptr\fP\fB, png_const_charp \fIerror\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_free (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fIptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_free_chunk_list (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_free_default(png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fIptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_free_data (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fInum\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_bit_depth (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_bKGD (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_color_16p \fI*background\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_channels (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_cHRM (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, double \fP\fI*white_x\fP\fB, double \fP\fI*white_y\fP\fB, double \fP\fI*red_x\fP\fB, double \fP\fI*red_y\fP\fB, double \fP\fI*green_x\fP\fB, double \fP\fI*green_y\fP\fB, double \fP\fI*blue_x\fP\fB, double \fI*blue_y\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_cHRM_fixed (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fI*white_x\fP\fB, png_uint_32 \fP\fI*white_y\fP\fB, png_uint_32 \fP\fI*red_x\fP\fB, png_uint_32 \fP\fI*red_y\fP\fB, png_uint_32 \fP\fI*green_x\fP\fB, png_uint_32 \fP\fI*green_y\fP\fB, png_uint_32 \fP\fI*blue_x\fP\fB, png_uint_32 \fI*blue_y\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_color_type (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_compression_type (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_copyright (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_get_error_ptr (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_filter_type (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_gAMA (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, double \fI*file_gamma\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_gAMA_fixed (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fI*int_file_gamma\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_header_ver (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_header_version (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_hIST (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_16p \fI*hist\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_iCCP (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_charpp \fP\fIname\fP\fB, int \fP\fI*compression_type\fP\fB, png_charpp \fP\fIprofile\fP\fB, png_uint_32 \fI*proflen\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_IHDR (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fI*width\fP\fB, png_uint_32 \fP\fI*height\fP\fB, int \fP\fI*bit_depth\fP\fB, int \fP\fI*color_type\fP\fB, int \fP\fI*interlace_type\fP\fB, int \fP\fI*compression_type\fP\fB, int \fI*filter_type\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_image_height (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_image_width (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_interlace_type (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_get_io_ptr (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_libpng_ver (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_get_mem_ptr(png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_oFFs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fI*offset_x\fP\fB, png_uint_32 \fP\fI*offset_y\fP\fB, int \fI*unit_type\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_pCAL (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_charp \fP\fI*purpose\fP\fB, png_int_32 \fP\fI*X0\fP\fB, png_int_32 \fP\fI*X1\fP\fB, int \fP\fI*type\fP\fB, int \fP\fI*nparams\fP\fB, png_charp \fP\fI*units\fP\fB, png_charpp \fI*params\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_pHYs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fI*res_x\fP\fB, png_uint_32 \fP\fI*res_y\fP\fB, int \fI*unit_type\fP\fB);\fP
+
+\fI\fB
+
+\fBfloat png_get_pixel_aspect_ratio (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_pixels_per_meter (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_get_progressive_ptr (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_PLTE (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_colorp \fP\fI*palette\fP\fB, int \fI*num_palette\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_rgb_to_gray_status (png_structp \fIpng_ptr)
+
+\fBpng_uint_32 png_get_rowbytes (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_bytepp png_get_rows (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_sBIT (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_color_8p \fI*sig_bit\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_bytep png_get_signature (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_sPLT (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_spalette_p \fI*splt_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_sRGB (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fI*intent\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_text (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_textp \fP\fI*text_ptr\fP\fB, int \fI*num_text\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_tIME (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_timep \fI*mod_time\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_tRNS (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_bytep \fP\fI*trans\fP\fB, int \fP\fI*num_trans\fP\fB, png_color_16p \fI*trans_values\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_unknown_chunks (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_unknown_chunkpp \fIunknowns\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_get_user_chunk_ptr (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_user_height_max( png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_get_user_transform_ptr (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_user_width_max (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_valid (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIflag\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_int_32 png_get_x_offset_microns (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_int_32 png_get_x_offset_pixels (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_x_pixels_per_meter (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_int_32 png_get_y_offset_microns (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_int_32 png_get_y_offset_pixels (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_y_pixels_per_meter (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_compression_buffer_size (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_handle_as_unknown (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fIchunk_name\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_init_io (png_structp \fP\fIpng_ptr\fP\fB, FILE \fI*fp\fP\fB);\fP
+
+\fI\fB
+
+\fBDEPRECATED: void png_info_init (png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBDEPRECATED: void png_info_init_2 (png_infopp \fP\fIptr_ptr\fP\fB, png_size_t \fIpng_info_struct_size\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_malloc (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_malloc_default(png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBvoidp png_memcpy (png_voidp \fP\fIs1\fP\fB, png_voidp \fP\fIs2\fP\fB, png_size_t \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_memcpy_check (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIs1\fP\fB, png_voidp \fP\fIs2\fP\fB, png_uint_32 \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBvoidp png_memset (png_voidp \fP\fIs1\fP\fB, int \fP\fIvalue\fP\fB, png_size_t \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_memset_check (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIs1\fP\fB, int \fP\fIvalue\fP\fB, png_uint_32 \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBDEPRECATED: void png_permit_empty_plte (png_structp \fP\fIpng_ptr\fP\fB, int \fIempty_plte_permitted\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_process_data (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_bytep \fP\fIbuffer\fP\fB, png_size_t \fIbuffer_size\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_progressive_combine_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIold_row\fP\fB, png_bytep \fInew_row\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_destroy (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_infop \fIend_info_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_end (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_image (png_structp \fP\fIpng_ptr\fP\fB, png_bytepp \fIimage\fP\fB);\fP
+
+\fI\fB
+
+\fBDEPRECATED: void png_read_init (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBDEPRECATED: void png_read_init_2 (png_structpp \fP\fIptr_ptr\fP\fB, png_const_charp \fP\fIuser_png_ver\fP\fB, png_size_t \fP\fIpng_struct_size\fP\fB, png_size_t \fIpng_info_size\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_info (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_png (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fP\fItransforms\fP\fB, png_voidp \fIparams\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIrow\fP\fB, png_bytep \fIdisplay_row\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_rows (png_structp \fP\fIpng_ptr\fP\fB, png_bytepp \fP\fIrow\fP\fB, png_bytepp \fP\fIdisplay_row\fP\fB, png_uint_32 \fInum_rows\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_update_info (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fB#if \fI!defined(PNG_1_0_X)
+
+\fBvoid png_set_add_alpha (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIfiller\fP\fB, int \fIflags\fP\fB);\fP
+
+\fI\fB#endif
+
+\fI\fB
+
+\fBvoid png_set_background (png_structp \fP\fIpng_ptr\fP\fB, png_color_16p \fP\fIbackground_color\fP\fB, int \fP\fIbackground_gamma_code\fP\fB, int \fP\fIneed_expand\fP\fB, double \fIbackground_gamma\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_bgr (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_bKGD (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_color_16p \fIbackground\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_cHRM (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, double \fP\fIwhite_x\fP\fB, double \fP\fIwhite_y\fP\fB, double \fP\fIred_x\fP\fB, double \fP\fIred_y\fP\fB, double \fP\fIgreen_x\fP\fB, double \fP\fIgreen_y\fP\fB, double \fP\fIblue_x\fP\fB, double \fIblue_y\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_cHRM_fixed (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fIwhite_x\fP\fB, png_uint_32 \fP\fIwhite_y\fP\fB, png_uint_32 \fP\fIred_x\fP\fB, png_uint_32 \fP\fIred_y\fP\fB, png_uint_32 \fP\fIgreen_x\fP\fB, png_uint_32 \fP\fIgreen_y\fP\fB, png_uint_32 \fP\fIblue_x\fP\fB, png_uint_32 \fIblue_y\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_compression_level (png_structp \fP\fIpng_ptr\fP\fB, int \fIlevel\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_compression_mem_level (png_structp \fP\fIpng_ptr\fP\fB, int \fImem_level\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_compression_method (png_structp \fP\fIpng_ptr\fP\fB, int \fImethod\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_compression_strategy (png_structp \fP\fIpng_ptr\fP\fB, int \fIstrategy\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_compression_window_bits (png_structp \fP\fIpng_ptr\fP\fB, int \fIwindow_bits\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_crc_action (png_structp \fP\fIpng_ptr\fP\fB, int \fP\fIcrit_action\fP\fB, int \fIancil_action\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_dither (png_structp \fP\fIpng_ptr\fP\fB, png_colorp \fP\fIpalette\fP\fB, int \fP\fInum_palette\fP\fB, int \fP\fImaximum_colors\fP\fB, png_uint_16p \fP\fIhistogram\fP\fB, int \fIfull_dither\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_error_fn (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIerror_ptr\fP\fB, png_error_ptr \fP\fIerror_fn\fP\fB, png_error_ptr \fIwarning_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_expand (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_filler (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIfiller\fP\fB, int \fIflags\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_filter (png_structp \fP\fIpng_ptr\fP\fB, int \fP\fImethod\fP\fB, int \fIfilters\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_filter_heuristics (png_structp \fP\fIpng_ptr\fP\fB, int \fP\fIheuristic_method\fP\fB, int \fP\fInum_weights\fP\fB, png_doublep \fP\fIfilter_weights\fP\fB, png_doublep \fIfilter_costs\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_flush (png_structp \fP\fIpng_ptr\fP\fB, int \fInrows\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_gamma (png_structp \fP\fIpng_ptr\fP\fB, double \fP\fIscreen_gamma\fP\fB, double \fIdefault_file_gamma\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_gAMA (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, double \fIfile_gamma\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_gAMA_fixed (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIfile_gamma\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_gray_1_2_4_to_8(png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_gray_to_rgb (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_hIST (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_16p \fIhist\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_iCCP (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_charp \fP\fIname\fP\fB, int \fP\fIcompression_type\fP\fB, png_charp \fP\fIprofile\fP\fB, png_uint_32 \fIproflen\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_set_interlace_handling (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_invalid (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fImask\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_invert_alpha (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_invert_mono (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_IHDR (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fIwidth\fP\fB, png_uint_32 \fP\fIheight\fP\fB, int \fP\fIbit_depth\fP\fB, int \fP\fIcolor_type\fP\fB, int \fP\fIinterlace_type\fP\fB, int \fP\fIcompression_type\fP\fB, int \fIfilter_type\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_keep_unknown_chunks (png_structp \fP\fIpng_ptr\fP\fB, int \fP\fIkeep\fP\fB, png_bytep \fP\fIchunk_list\fP\fB, int \fInum_chunks\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_mem_fn(png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fImem_ptr\fP\fB, png_malloc_ptr \fP\fImalloc_fn\fP\fB, png_free_ptr \fIfree_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_oFFs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fIoffset_x\fP\fB, png_uint_32 \fP\fIoffset_y\fP\fB, int \fIunit_type\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_packing (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_packswap (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_palette_to_rgb(png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_pCAL (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_charp \fP\fIpurpose\fP\fB, png_int_32 \fP\fIX0\fP\fB, png_int_32 \fP\fIX1\fP\fB, int \fP\fItype\fP\fB, int \fP\fInparams\fP\fB, png_charp \fP\fIunits\fP\fB, png_charpp \fIparams\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_pHYs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fIres_x\fP\fB, png_uint_32 \fP\fIres_y\fP\fB, int \fIunit_type\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_progressive_read_fn (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIprogressive_ptr\fP\fB, png_progressive_info_ptr \fP\fIinfo_fn\fP\fB, png_progressive_row_ptr \fP\fIrow_fn\fP\fB, png_progressive_end_ptr \fIend_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_PLTE (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_colorp \fP\fIpalette\fP\fB, int \fInum_palette\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_read_fn (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIio_ptr\fP\fB, png_rw_ptr \fIread_data_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_read_status_fn (png_structp \fP\fIpng_ptr\fP\fB, png_read_status_ptr \fIread_row_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_read_user_transform_fn (png_structp \fP\fIpng_ptr\fP\fB, png_user_transform_ptr \fIread_user_transform_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_rgb_to_gray (png_structp \fP\fIpng_ptr\fP\fB, int \fP\fIerror_action\fP\fB, double \fP\fIred\fP\fB, double \fIgreen\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_rgb_to_gray_fixed (png_structp \fP\fIpng_ptr\fP\fB, int error_action png_fixed_point \fP\fIred\fP\fB, png_fixed_point \fIgreen\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_rows (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_bytepp \fIrow_pointers\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_sBIT (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_color_8p \fIsig_bit\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_sCAL (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_charp \fP\fIunit\fP\fB, double \fP\fIwidth\fP\fB, double \fIheight\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_shift (png_structp \fP\fIpng_ptr\fP\fB, png_color_8p \fItrue_bits\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_sig_bytes (png_structp \fP\fIpng_ptr\fP\fB, int \fInum_bytes\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_sPLT (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_spalette_p \fP\fIsplt_ptr\fP\fB, int \fInum_spalettes\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_sRGB (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fIintent\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_sRGB_gAMA_and_cHRM (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fIintent\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_strip_16 (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_strip_alpha (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_swap (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_swap_alpha (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_text (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_textp \fP\fItext_ptr\fP\fB, int \fInum_text\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_tIME (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_timep \fImod_time\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_tRNS (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_bytep \fP\fItrans\fP\fB, int \fP\fInum_trans\fP\fB, png_color_16p \fItrans_values\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_tRNS_to_alpha(png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_set_unknown_chunks (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_unknown_chunkp \fP\fIunknowns\fP\fB, int \fP\fInum\fP\fB, int \fIlocation\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_unknown_chunk_location(png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fP\fIchunk\fP\fB, int \fIlocation\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_read_user_chunk_fn (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIuser_chunk_ptr\fP\fB, png_user_chunk_ptr \fIread_user_chunk_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_user_limits (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIuser_width_max\fP\fB, png_uint_32 \fIuser_height_max\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_user_transform_info (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIuser_transform_ptr\fP\fB, int \fP\fIuser_transform_depth\fP\fB, int \fIuser_transform_channels\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_write_fn (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIio_ptr\fP\fB, png_rw_ptr \fP\fIwrite_data_fn\fP\fB, png_flush_ptr \fIoutput_flush_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_write_status_fn (png_structp \fP\fIpng_ptr\fP\fB, png_write_status_ptr \fIwrite_row_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_write_user_transform_fn (png_structp \fP\fIpng_ptr\fP\fB, png_user_transform_ptr \fIwrite_user_transform_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_compression_buffer_size(png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_sig_cmp (png_bytep \fP\fIsig\fP\fB, png_size_t \fP\fIstart\fP\fB, png_size_t \fInum_to_check\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_start_read_image (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_warning (png_structp \fP\fIpng_ptr\fP\fB, png_const_charp \fImessage\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_chunk (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIchunk_name\fP\fB, png_bytep \fP\fIdata\fP\fB, png_size_t \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_chunk_data (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIdata\fP\fB, png_size_t \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_chunk_end (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_chunk_start (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIchunk_name\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_destroy (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_end (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_flush (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_image (png_structp \fP\fIpng_ptr\fP\fB, png_bytepp \fIimage\fP\fB);\fP
+
+\fI\fB
+
+\fBDEPRECATED: void png_write_init (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBDEPRECATED: void png_write_init_2 (png_structpp \fP\fIptr_ptr\fP\fB, png_const_charp \fP\fIuser_png_ver\fP\fB, png_size_t \fP\fIpng_struct_size\fP\fB, png_size_t \fIpng_info_size\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_info (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_info_before_PLTE (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_png (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fP\fItransforms\fP\fB, png_voidp \fIparams\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_rows (png_structp \fP\fIpng_ptr\fP\fB, png_bytepp \fP\fIrow\fP\fB, png_uint_32 \fInum_rows\fP\fB);\fP
+
+\fI\fB
+
+\fBvoidpf png_zalloc (voidpf \fP\fIpng_ptr\fP\fB, uInt \fP\fIitems\fP\fB, uInt \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_zfree (voidpf \fP\fIpng_ptr\fP\fB, voidpf \fIptr\fP\fB);\fP
+
+\fI\fB
+
+.SH DESCRIPTION
+The
+.I libpng
+library supports encoding, decoding, and various manipulations of
+the Portable Network Graphics (PNG) format image files.  It uses the
+.IR zlib(3)
+compression library.
+Following is a copy of the libpng.txt file that accompanies libpng.
+.SH LIBPNG.TXT
+libpng.txt - A description on how to use and modify libpng
+
+ libpng version 1.2.8 - December 3, 2004
+ Updated and distributed by Glenn Randers-Pehrson
+ <glennrp at users.sourceforge.net>
+ Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ For conditions of distribution and use, see copyright
+ notice in png.h.
+
+ based on:
+
+ libpng 1.0 beta 6  version 0.96 May 28, 1997
+ Updated and distributed by Andreas Dilger
+ Copyright (c) 1996, 1997 Andreas Dilger
+
+ libpng 1.0 beta 2 - version 0.88  January 26, 1996
+ For conditions of distribution and use, see copyright
+ notice in png.h. Copyright (c) 1995, 1996 Guy Eric
+ Schalnat, Group 42, Inc.
+
+ Updated/rewritten per request in the libpng FAQ
+ Copyright (c) 1995, 1996 Frank J. T. Wojcik
+ December 18, 1995 & January 20, 1996
+
+.SH I. Introduction
+
+This file describes how to use and modify the PNG reference library
+(known as libpng) for your own use.  There are five sections to this
+file: introduction, structures, reading, writing, and modification and
+configuration notes for various special platforms.  In addition to this
+file, example.c is a good starting point for using the library, as
+it is heavily commented and should include everything most people
+will need.  We assume that libpng is already installed; see the
+INSTALL file for instructions on how to install libpng.
+
+Libpng was written as a companion to the PNG specification, as a way
+of reducing the amount of time and effort it takes to support the PNG
+file format in application programs.
+
+The PNG specification (second edition), November 2003, is available as
+a W3C Recommendation and as an ISO Standard (ISO/IEC 15948:2003 (E)) at
+<http://www.w3.org/TR/2003/REC-PNG-20031110/
+The W3C and ISO documents have identical technical content.
+
+The PNG-1.2 specification is available at
+<http://www.libpng.org/pub/png/documents/>
+
+The PNG-1.0 specification is available
+as RFC 2083 <http://www.libpng.org/pub/png/documents/> and as a
+W3C Recommendation <http://www.w3.org/TR/REC.png.html>. Some
+additional chunks are described in the special-purpose public chunks
+documents at <http://www.libpng.org/pub/png/documents/>.
+
+Other information
+about PNG, and the latest version of libpng, can be found at the PNG home
+page, <http://www.libpng.org/pub/png/>.
+
+Most users will not have to modify the library significantly; advanced
+users may want to modify it more.  All attempts were made to make it as
+complete as possible, while keeping the code easy to understand.
+Currently, this library only supports C.  Support for other languages
+is being considered.
+
+Libpng has been designed to handle multiple sessions at one time,
+to be easily modifiable, to be portable to the vast majority of
+machines (ANSI, K&R, 16-, 32-, and 64-bit) available, and to be easy
+to use.  The ultimate goal of libpng is to promote the acceptance of
+the PNG file format in whatever way possible.  While there is still
+work to be done (see the TODO file), libpng should cover the
+majority of the needs of its users.
+
+Libpng uses zlib for its compression and decompression of PNG files.
+Further information about zlib, and the latest version of zlib, can
+be found at the zlib home page, <http://www.info-zip.org/pub/infozip/zlib/>.
+The zlib compression utility is a general purpose utility that is
+useful for more than PNG files, and can be used without libpng.
+See the documentation delivered with zlib for more details.
+You can usually find the source files for the zlib utility wherever you
+find the libpng source files.
+
+Libpng is thread safe, provided the threads are using different
+instances of the structures.  Each thread should have its own
+png_struct and png_info instances, and thus its own image.
+Libpng does not protect itself against two threads using the
+same instance of a structure.  Note: thread safety may be defeated
+by use of some of the MMX assembler code in pnggccrd.c, which is only
+compiled when the user defines PNG_THREAD_UNSAFE_OK.
+
+.SH II. Structures
+
+There are two main structures that are important to libpng, png_struct
+and png_info.  The first, png_struct, is an internal structure that
+will not, for the most part, be used by a user except as the first
+variable passed to every libpng function call.
+
+The png_info structure is designed to provide information about the
+PNG file.  At one time, the fields of png_info were intended to be
+directly accessible to the user.  However, this tended to cause problems
+with applications using dynamically loaded libraries, and as a result
+a set of interface functions for png_info (the png_get_*() and png_set_*()
+functions) was developed.  The fields of png_info are still available for
+older applications, but it is suggested that applications use the new
+interfaces if at all possible.
+
+Applications that do make direct access to the members of png_struct (except
+for png_ptr->jmpbuf) must be recompiled whenever the library is updated,
+and applications that make direct access to the members of png_info must
+be recompiled if they were compiled or loaded with libpng version 1.0.6,
+in which the members were in a different order.  In version 1.0.7, the
+members of the png_info structure reverted to the old order, as they were
+in versions 0.97c through 1.0.5.  Starting with version 2.0.0, both
+structures are going to be hidden, and the contents of the structures will
+only be accessible through the png_get/png_set functions.
+
+The png.h header file is an invaluable reference for programming with libpng.
+And while I'm on the topic, make sure you include the libpng header file:
+
+#include <png.h>
+
+.SH III. Reading
+
+We'll now walk you through the possible functions to call when reading
+in a PNG file sequentially, briefly explaining the syntax and purpose
+of each one.  See example.c and png.h for more detail.  While
+progressive reading is covered in the next section, you will still
+need some of the functions discussed in this section to read a PNG
+file.
+
+.SS Setup
+
+You will want to do the I/O initialization(*) before you get into libpng,
+so if it doesn't work, you don't have much to undo.  Of course, you
+will also want to insure that you are, in fact, dealing with a PNG
+file.  Libpng provides a simple check to see if a file is a PNG file.
+To use it, pass in the first 1 to 8 bytes of the file to the function
+png_sig_cmp(), and it will return 0 if the bytes match the corresponding
+bytes of the PNG signature, or nonzero otherwise.  Of course, the more bytes
+you pass in, the greater the accuracy of the prediction.
+
+If you are intending to keep the file pointer open for use in libpng,
+you must ensure you don't read more than 8 bytes from the beginning
+of the file, and you also have to make a call to png_set_sig_bytes_read()
+with the number of bytes you read from the beginning.  Libpng will
+then only check the bytes (if any) that your program didn't read.
+
+(*): If you are not using the standard I/O functions, you will need
+to replace them with custom functions.  See the discussion under
+Customizing libpng.
+
+
+    FILE *fp = fopen(file_name, "rb");
+    if (!fp)
+    {
+        return (ERROR);
+    }
+    fread(header, 1, number, fp);
+    is_png = !png_sig_cmp(header, 0, number);
+    if (!is_png)
+    {
+        return (NOT_PNG);
+    }
+
+
+Next, png_struct and png_info need to be allocated and initialized.  In
+order to ensure that the size of these structures is correct even with a
+dynamically linked libpng, there are functions to initialize and
+allocate the structures.  We also pass the library version, optional
+pointers to error handling functions, and a pointer to a data struct for
+use by the error functions, if necessary (the pointer and functions can
+be NULL if the default error handlers are to be used).  See the section
+on Changes to Libpng below regarding the old initialization functions.
+The structure allocation functions quietly return NULL if they fail to
+create the structure, so your application should check for that.
+
+    png_structp png_ptr = png_create_read_struct
+       (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+        user_error_fn, user_warning_fn);
+    if (!png_ptr)
+        return (ERROR);
+
+    png_infop info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr)
+    {
+        png_destroy_read_struct(&png_ptr,
+           (png_infopp)NULL, (png_infopp)NULL);
+        return (ERROR);
+    }
+
+    png_infop end_info = png_create_info_struct(png_ptr);
+    if (!end_info)
+    {
+        png_destroy_read_struct(&png_ptr, &info_ptr,
+          (png_infopp)NULL);
+        return (ERROR);
+    }
+
+If you want to use your own memory allocation routines,
+define PNG_USER_MEM_SUPPORTED and use
+png_create_read_struct_2() instead of png_create_read_struct():
+
+    png_structp png_ptr = png_create_read_struct_2
+       (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+        user_error_fn, user_warning_fn, (png_voidp)
+        user_mem_ptr, user_malloc_fn, user_free_fn);
+
+The error handling routines passed to png_create_read_struct()
+and the memory alloc/free routines passed to png_create_struct_2()
+are only necessary if you are not using the libpng supplied error
+handling and memory alloc/free functions.
+
+When libpng encounters an error, it expects to longjmp back
+to your routine.  Therefore, you will need to call setjmp and pass
+your png_jmpbuf(png_ptr).  If you read the file from different
+routines, you will need to update the jmpbuf field every time you enter
+a new routine that will call a png_*() function.
+
+See your documentation of setjmp/longjmp for your compiler for more
+information on setjmp/longjmp.  See the discussion on libpng error
+handling in the Customizing Libpng section below for more information
+on the libpng error handling.  If an error occurs, and libpng longjmp's
+back to your setjmp, you will want to call png_destroy_read_struct() to
+free any memory.
+
+    if (setjmp(png_jmpbuf(png_ptr)))
+    {
+        png_destroy_read_struct(&png_ptr, &info_ptr,
+           &end_info);
+        fclose(fp);
+        return (ERROR);
+    }
+
+If you would rather avoid the complexity of setjmp/longjmp issues,
+you can compile libpng with PNG_SETJMP_NOT_SUPPORTED, in which case
+errors will result in a call to PNG_ABORT() which defaults to abort().
+
+Now you need to set up the input code.  The default for libpng is to
+use the C function fread().  If you use this, you will need to pass a
+valid FILE * in the function png_init_io().  Be sure that the file is
+opened in binary mode.  If you wish to handle reading data in another
+way, you need not call the png_init_io() function, but you must then
+implement the libpng I/O methods discussed in the Customizing Libpng
+section below.
+
+    png_init_io(png_ptr, fp);
+
+If you had previously opened the file and read any of the signature from
+the beginning in order to see if this was a PNG file, you need to let
+libpng know that there are some bytes missing from the start of the file.
+
+    png_set_sig_bytes(png_ptr, number);
+
+.SS Setting up callback code
+
+You can set up a callback function to handle any unknown chunks in the
+input stream. You must supply the function
+
+    read_chunk_callback(png_ptr ptr,
+         png_unknown_chunkp chunk);
+    {
+       /* The unknown chunk structure contains your
+          chunk data: */
+           png_byte name[5];
+           png_byte *data;
+           png_size_t size;
+       /* Note that libpng has already taken care of
+          the CRC handling */
+
+       /* put your code here.  Return one of the
+          following: */
+
+       return (-n); /* chunk had an error */
+       return (0); /* did not recognize */
+       return (n); /* success */
+    }
+
+(You can give your function another name that you like instead of
+"read_chunk_callback")
+
+To inform libpng about your function, use
+
+    png_set_read_user_chunk_fn(png_ptr, user_chunk_ptr,
+        read_chunk_callback);
+
+This names not only the callback function, but also a user pointer that
+you can retrieve with
+
+    png_get_user_chunk_ptr(png_ptr);
+
+At this point, you can set up a callback function that will be
+called after each row has been read, which you can use to control
+a progress meter or the like.  It's demonstrated in pngtest.c.
+You must supply a function
+
+    void read_row_callback(png_ptr ptr, png_uint_32 row,
+       int pass);
+    {
+      /* put your code here */
+    }
+
+(You can give it another name that you like instead of "read_row_callback")
+
+To inform libpng about your function, use
+
+    png_set_read_status_fn(png_ptr, read_row_callback);
+
+.SS Width and height limits
+
+The PNG specification allows the width and height of an image to be as
+large as 2^31-1 (0x7fffffff), or about 2.147 billion rows and columns.
+Since very few applications really need to process such large images,
+we have imposed an arbitrary 1-million limit on rows and columns.
+Larger images will be rejected immediately with a png_error() call. If
+you wish to override this limit, you can use
+
+   png_set_user_limits(png_ptr, width_max, height_max);
+
+to set your own limits, or use width_max = height_max = 0x7fffffffL
+to allow all valid dimensions (libpng may reject some very large images
+anyway because of potential buffer overflow conditions).
+
+You should put this statement after you create the PNG structure and
+before calling png_read_info(), png_read_png(), or png_process_data().
+If you need to retrieve the limits that are being applied, use
+
+   width_max = png_get_user_width_max(png_ptr);
+   height_max = png_get_user_height_max(png_ptr);
+
+.SS Unknown-chunk handling
+
+Now you get to set the way the library processes unknown chunks in the
+input PNG stream. Both known and unknown chunks will be read.  Normal
+behavior is that known chunks will be parsed into information in
+various info_ptr members; unknown chunks will be discarded. To change
+this, you can call:
+
+    png_set_keep_unknown_chunks(png_ptr, keep,
+        chunk_list, num_chunks);
+    keep       - 0: do not handle as unknown
+                 1: do not keep
+                 2: keep only if safe-to-copy
+                 3: keep even if unsafe-to-copy
+               You can use these definitions:
+                 PNG_HANDLE_CHUNK_AS_DEFAULT   0
+                 PNG_HANDLE_CHUNK_NEVER        1
+                 PNG_HANDLE_CHUNK_IF_SAFE      2
+                 PNG_HANDLE_CHUNK_ALWAYS       3
+    chunk_list - list of chunks affected (a byte string,
+                 five bytes per chunk, NULL or '\0' if
+                 num_chunks is 0)
+    num_chunks - number of chunks affected; if 0, all
+                 unknown chunks are affected.  If nonzero,
+                 only the chunks in the list are affected
+
+Unknown chunks declared in this way will be saved as raw data onto a
+list of png_unknown_chunk structures.  If a chunk that is normally
+known to libpng is named in the list, it will be handled as unknown,
+according to the "keep" directive.  If a chunk is named in successive
+instances of png_set_keep_unknown_chunks(), the final instance will
+take precedence.  The IHDR and IEND chunks should not be named in
+chunk_list; if they are, libpng will process them normally anyway.
+
+.SS The high-level read interface
+
+At this point there are two ways to proceed; through the high-level
+read interface, or through a sequence of low-level read operations.
+You can use the high-level interface if (a) you are willing to read
+the entire image into memory, and (b) the input transformations
+you want to do are limited to the following set:
+
+    PNG_TRANSFORM_IDENTITY      No transformation
+    PNG_TRANSFORM_STRIP_16      Strip 16-bit samples to
+                                8 bits
+    PNG_TRANSFORM_STRIP_ALPHA   Discard the alpha channel
+    PNG_TRANSFORM_PACKING       Expand 1, 2 and 4-bit
+                                samples to bytes
+    PNG_TRANSFORM_PACKSWAP      Change order of packed
+                                pixels to LSB first
+    PNG_TRANSFORM_EXPAND        Perform set_expand()
+    PNG_TRANSFORM_INVERT_MONO   Invert monochrome images
+    PNG_TRANSFORM_SHIFT         Normalize pixels to the
+                                sBIT depth
+    PNG_TRANSFORM_BGR           Flip RGB to BGR, RGBA
+                                to BGRA
+    PNG_TRANSFORM_SWAP_ALPHA    Flip RGBA to ARGB or GA
+                                to AG
+    PNG_TRANSFORM_INVERT_ALPHA  Change alpha from opacity
+                                to transparency
+    PNG_TRANSFORM_SWAP_ENDIAN   Byte-swap 16-bit samples
+
+(This excludes setting a background color, doing gamma transformation,
+dithering, and setting filler.)  If this is the case, simply do this:
+
+    png_read_png(png_ptr, info_ptr, png_transforms, NULL)
+
+where png_transforms is an integer containing the logical OR of
+some set of transformation flags.  This call is equivalent to png_read_info(),
+followed the set of transformations indicated by the transform mask,
+then png_read_image(), and finally png_read_end().
+
+(The final parameter of this call is not yet used.  Someday it might point
+to transformation parameters required by some future input transform.)
+
+You must use png_transforms and not call any png_set_transform() functions
+when you use png_read_png().
+
+After you have called png_read_png(), you can retrieve the image data
+with
+
+   row_pointers = png_get_rows(png_ptr, info_ptr);
+
+where row_pointers is an array of pointers to the pixel data for each row:
+
+   png_bytep row_pointers[height];
+
+If you know your image size and pixel size ahead of time, you can allocate
+row_pointers prior to calling png_read_png() with
+
+   if (height > PNG_UINT_32_MAX/png_sizeof(png_byte))
+      png_error (png_ptr,
+         "Image is too tall to process in memory");
+   if (width > PNG_UINT_32_MAX/pixel_size)
+      png_error (png_ptr,
+         "Image is too wide to process in memory");
+   row_pointers = png_malloc(png_ptr,
+      height*png_sizeof(png_bytep));
+   for (int i=0; i<height, i++)
+      row_pointers[i]=png_malloc(png_ptr,
+         width*pixel_size);
+   png_set_rows(png_ptr, info_ptr, &row_pointers);
+
+Alternatively you could allocate your image in one big block and define
+row_pointers[i] to point into the proper places in your block.
+
+If you use png_set_rows(), the application is responsible for freeing
+row_pointers (and row_pointers[i], if they were separately allocated).
+
+If you don't allocate row_pointers ahead of time, png_read_png() will
+do it, and it'll be free'ed when you call png_destroy_*().
+
+.SS The low-level read interface
+
+If you are going the low-level route, you are now ready to read all
+the file information up to the actual image data.  You do this with a
+call to png_read_info().
+
+    png_read_info(png_ptr, info_ptr);
+
+This will process all chunks up to but not including the image data.
+
+.SS Querying the info structure
+
+Functions are used to get the information from the info_ptr once it
+has been read.  Note that these fields may not be completely filled
+in until png_read_end() has read the chunk data following the image.
+
+    png_get_IHDR(png_ptr, info_ptr, &width, &height,
+       &bit_depth, &color_type, &interlace_type,
+       &compression_type, &filter_method);
+
+    width          - holds the width of the image
+                     in pixels (up to 2^31).
+    height         - holds the height of the image
+                     in pixels (up to 2^31).
+    bit_depth      - holds the bit depth of one of the
+                     image channels.  (valid values are
+                     1, 2, 4, 8, 16 and depend also on
+                     the color_type.  See also
+                     significant bits (sBIT) below).
+    color_type     - describes which color/alpha channels
+                         are present.
+                     PNG_COLOR_TYPE_GRAY
+                        (bit depths 1, 2, 4, 8, 16)
+                     PNG_COLOR_TYPE_GRAY_ALPHA
+                        (bit depths 8, 16)
+                     PNG_COLOR_TYPE_PALETTE
+                        (bit depths 1, 2, 4, 8)
+                     PNG_COLOR_TYPE_RGB
+                        (bit_depths 8, 16)
+                     PNG_COLOR_TYPE_RGB_ALPHA
+                        (bit_depths 8, 16)
+
+                     PNG_COLOR_MASK_PALETTE
+                     PNG_COLOR_MASK_COLOR
+                     PNG_COLOR_MASK_ALPHA
+
+    filter_method  - (must be PNG_FILTER_TYPE_BASE
+                     for PNG 1.0, and can also be
+                     PNG_INTRAPIXEL_DIFFERENCING if
+                     the PNG datastream is embedded in
+                     a MNG-1.0 datastream)
+    compression_type - (must be PNG_COMPRESSION_TYPE_BASE
+                     for PNG 1.0)
+    interlace_type - (PNG_INTERLACE_NONE or
+                     PNG_INTERLACE_ADAM7)
+    Any or all of interlace_type, compression_type, of
+    filter_method can be NULL if you are
+    not interested in their values.
+
+    channels = png_get_channels(png_ptr, info_ptr);
+    channels       - number of channels of info for the
+                     color type (valid values are 1 (GRAY,
+                     PALETTE), 2 (GRAY_ALPHA), 3 (RGB),
+                     4 (RGB_ALPHA or RGB + filler byte))
+    rowbytes = png_get_rowbytes(png_ptr, info_ptr);
+    rowbytes       - number of bytes needed to hold a row
+
+    signature = png_get_signature(png_ptr, info_ptr);
+    signature      - holds the signature read from the
+                     file (if any).  The data is kept in
+                     the same offset it would be if the
+                     whole signature were read (i.e. if an
+                     application had already read in 4
+                     bytes of signature before starting
+                     libpng, the remaining 4 bytes would
+                     be in signature[4] through signature[7]
+                     (see png_set_sig_bytes())).
+
+
+    width            = png_get_image_width(png_ptr,
+                         info_ptr);
+    height           = png_get_image_height(png_ptr,
+                         info_ptr);
+    bit_depth        = png_get_bit_depth(png_ptr,
+                         info_ptr);
+    color_type       = png_get_color_type(png_ptr,
+                         info_ptr);
+    filter_method    = png_get_filter_type(png_ptr,
+                         info_ptr);
+    compression_type = png_get_compression_type(png_ptr,
+                         info_ptr);
+    interlace_type   = png_get_interlace_type(png_ptr,
+                         info_ptr);
+
+
+These are also important, but their validity depends on whether the chunk
+has been read.  The png_get_valid(png_ptr, info_ptr, PNG_INFO_<chunk>) and
+png_get_<chunk>(png_ptr, info_ptr, ...) functions return non-zero if the
+data has been read, or zero if it is missing.  The parameters to the
+png_get_<chunk> are set directly if they are simple data types, or a pointer
+into the info_ptr is returned for any complex types.
+
+    png_get_PLTE(png_ptr, info_ptr, &palette,
+                     &num_palette);
+    palette        - the palette for the file
+                     (array of png_color)
+    num_palette    - number of entries in the palette
+
+    png_get_gAMA(png_ptr, info_ptr, &gamma);
+    gamma          - the gamma the file is written
+                     at (PNG_INFO_gAMA)
+
+    png_get_sRGB(png_ptr, info_ptr, &srgb_intent);
+    srgb_intent    - the rendering intent (PNG_INFO_sRGB)
+                     The presence of the sRGB chunk
+                     means that the pixel data is in the
+                     sRGB color space.  This chunk also
+                     implies specific values of gAMA and
+                     cHRM.
+
+    png_get_iCCP(png_ptr, info_ptr, &name,
+       &compression_type, &profile, &proflen);
+    name            - The profile name.
+    compression     - The compression type; always
+                      PNG_COMPRESSION_TYPE_BASE for PNG 1.0.
+                      You may give NULL to this argument to
+                      ignore it.
+    profile         - International Color Consortium color
+                      profile data. May contain NULs.
+    proflen         - length of profile data in bytes.
+
+    png_get_sBIT(png_ptr, info_ptr, &sig_bit);
+    sig_bit        - the number of significant bits for
+                     (PNG_INFO_sBIT) each of the gray,
+                     red, green, and blue channels,
+                     whichever are appropriate for the
+                     given color type (png_color_16)
+
+    png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans,
+                     &trans_values);
+    trans          - array of transparent entries for
+                     palette (PNG_INFO_tRNS)
+    trans_values   - graylevel or color sample values of
+                     the single transparent color for
+                     non-paletted images (PNG_INFO_tRNS)
+    num_trans      - number of transparent entries
+                     (PNG_INFO_tRNS)
+
+    png_get_hIST(png_ptr, info_ptr, &hist);
+                     (PNG_INFO_hIST)
+    hist           - histogram of palette (array of
+                     png_uint_16)
+
+    png_get_tIME(png_ptr, info_ptr, &mod_time);
+    mod_time       - time image was last modified
+                    (PNG_VALID_tIME)
+
+    png_get_bKGD(png_ptr, info_ptr, &background);
+    background     - background color (PNG_VALID_bKGD)
+                     valid 16-bit red, green and blue
+                     values, regardless of color_type
+
+    num_comments   = png_get_text(png_ptr, info_ptr,
+                     &text_ptr, &num_text);
+    num_comments   - number of comments
+    text_ptr       - array of png_text holding image
+                     comments
+    text_ptr[i].compression - type of compression used
+                 on "text" PNG_TEXT_COMPRESSION_NONE
+                           PNG_TEXT_COMPRESSION_zTXt
+                           PNG_ITXT_COMPRESSION_NONE
+                           PNG_ITXT_COMPRESSION_zTXt
+    text_ptr[i].key   - keyword for comment.  Must contain
+                         1-79 characters.
+    text_ptr[i].text  - text comments for current
+                         keyword.  Can be empty.
+    text_ptr[i].text_length - length of text string,
+                 after decompression, 0 for iTXt
+    text_ptr[i].itxt_length - length of itxt string,
+                 after decompression, 0 for tEXt/zTXt
+    text_ptr[i].lang  - language of comment (empty
+                         string for unknown).
+    text_ptr[i].lang_key  - keyword in UTF-8
+                         (empty string for unknown).
+    num_text       - number of comments (same as
+                     num_comments; you can put NULL here
+                     to avoid the duplication)
+    Note while png_set_text() will accept text, language,
+    and translated keywords that can be NULL pointers, the
+    structure returned by png_get_text will always contain
+    regular zero-terminated C strings.  They might be
+    empty strings but they will never be NULL pointers.
+
+    num_spalettes = png_get_sPLT(png_ptr, info_ptr,
+       &palette_ptr);
+    palette_ptr    - array of palette structures holding
+                     contents of one or more sPLT chunks
+                     read.
+    num_spalettes  - number of sPLT chunks read.
+
+    png_get_oFFs(png_ptr, info_ptr, &offset_x, &offset_y,
+       &unit_type);
+    offset_x       - positive offset from the left edge
+                     of the screen
+    offset_y       - positive offset from the top edge
+                     of the screen
+    unit_type      - PNG_OFFSET_PIXEL, PNG_OFFSET_MICROMETER
+
+    png_get_pHYs(png_ptr, info_ptr, &res_x, &res_y,
+       &unit_type);
+    res_x          - pixels/unit physical resolution in
+                     x direction
+    res_y          - pixels/unit physical resolution in
+                     x direction
+    unit_type      - PNG_RESOLUTION_UNKNOWN,
+                     PNG_RESOLUTION_METER
+
+    png_get_sCAL(png_ptr, info_ptr, &unit, &width,
+       &height)
+    unit        - physical scale units (an integer)
+    width       - width of a pixel in physical scale units
+    height      - height of a pixel in physical scale units
+                 (width and height are doubles)
+
+    png_get_sCAL_s(png_ptr, info_ptr, &unit, &width,
+       &height)
+    unit        - physical scale units (an integer)
+    width       - width of a pixel in physical scale units
+    height      - height of a pixel in physical scale units
+                 (width and height are strings like "2.54")
+
+    num_unknown_chunks = png_get_unknown_chunks(png_ptr,
+       info_ptr, &unknowns)
+    unknowns          - array of png_unknown_chunk
+                        structures holding unknown chunks
+    unknowns[i].name  - name of unknown chunk
+    unknowns[i].data  - data of unknown chunk
+    unknowns[i].size  - size of unknown chunk's data
+    unknowns[i].location - position of chunk in file
+
+    The value of "i" corresponds to the order in which the
+    chunks were read from the PNG file or inserted with the
+    png_set_unknown_chunks() function.
+
+The data from the pHYs chunk can be retrieved in several convenient
+forms:
+
+    res_x = png_get_x_pixels_per_meter(png_ptr,
+       info_ptr)
+    res_y = png_get_y_pixels_per_meter(png_ptr,
+       info_ptr)
+    res_x_and_y = png_get_pixels_per_meter(png_ptr,
+       info_ptr)
+    res_x = png_get_x_pixels_per_inch(png_ptr,
+       info_ptr)
+    res_y = png_get_y_pixels_per_inch(png_ptr,
+       info_ptr)
+    res_x_and_y = png_get_pixels_per_inch(png_ptr,
+       info_ptr)
+    aspect_ratio = png_get_pixel_aspect_ratio(png_ptr,
+       info_ptr)
+
+   (Each of these returns 0 [signifying "unknown"] if
+       the data is not present or if res_x is 0;
+       res_x_and_y is 0 if res_x != res_y)
+
+The data from the oFFs chunk can be retrieved in several convenient
+forms:
+
+    x_offset = png_get_x_offset_microns(png_ptr, info_ptr);
+    y_offset = png_get_y_offset_microns(png_ptr, info_ptr);
+    x_offset = png_get_x_offset_inches(png_ptr, info_ptr);
+    y_offset = png_get_y_offset_inches(png_ptr, info_ptr);
+
+   (Each of these returns 0 [signifying "unknown" if both
+       x and y are 0] if the data is not present or if the
+       chunk is present but the unit is the pixel)
+
+For more information, see the png_info definition in png.h and the
+PNG specification for chunk contents.  Be careful with trusting
+rowbytes, as some of the transformations could increase the space
+needed to hold a row (expand, filler, gray_to_rgb, etc.).
+See png_read_update_info(), below.
+
+A quick word about text_ptr and num_text.  PNG stores comments in
+keyword/text pairs, one pair per chunk, with no limit on the number
+of text chunks, and a 2^31 byte limit on their size.  While there are
+suggested keywords, there is no requirement to restrict the use to these
+strings.  It is strongly suggested that keywords and text be sensible
+to humans (that's the point), so don't use abbreviations.  Non-printing
+symbols are not allowed.  See the PNG specification for more details.
+There is also no requirement to have text after the keyword.
+
+Keywords should be limited to 79 Latin-1 characters without leading or
+trailing spaces, but non-consecutive spaces are allowed within the
+keyword.  It is possible to have the same keyword any number of times.
+The text_ptr is an array of png_text structures, each holding a
+pointer to a language string, a pointer to a keyword and a pointer to
+a text string.  The text string, language code, and translated
+keyword may be empty or NULL pointers.  The keyword/text
+pairs are put into the array in the order that they are received.
+However, some or all of the text chunks may be after the image, so, to
+make sure you have read all the text chunks, don't mess with these
+until after you read the stuff after the image.  This will be
+mentioned again below in the discussion that goes with png_read_end().
+
+.SS Input transformations
+
+After you've read the header information, you can set up the library
+to handle any special transformations of the image data.  The various
+ways to transform the data will be described in the order that they
+should occur.  This is important, as some of these change the color
+type and/or bit depth of the data, and some others only work on
+certain color types and bit depths.  Even though each transformation
+checks to see if it has data that it can do something with, you should
+make sure to only enable a transformation if it will be valid for the
+data.  For example, don't swap red and blue on grayscale data.
+
+The colors used for the background and transparency values should be
+supplied in the same format/depth as the current image data.  They
+are stored in the same format/depth as the image data in a bKGD or tRNS
+chunk, so this is what libpng expects for this data.  The colors are
+transformed to keep in sync with the image data when an application
+calls the png_read_update_info() routine (see below).
+
+Data will be decoded into the supplied row buffers packed into bytes
+unless the library has been told to transform it into another format.
+For example, 4 bit/pixel paletted or grayscale data will be returned
+2 pixels/byte with the leftmost pixel in the high-order bits of the
+byte, unless png_set_packing() is called.  8-bit RGB data will be stored
+in RGB RGB RGB format unless png_set_filler() or png_set_add_alpha()
+is called to insert filler bytes, either before or after each RGB triplet.
+16-bit RGB data will be returned RRGGBB RRGGBB, with the most significant
+byte of the color value first, unless png_set_strip_16() is called to
+transform it to regular RGB RGB triplets, or png_set_filler() or
+png_set_add alpha() is called to insert filler bytes, either before or
+after each RRGGBB triplet.  Similarly, 8-bit or 16-bit grayscale data can
+be modified with
+png_set_filler(), png_set_add_alpha(), or png_set_strip_16().
+
+The following code transforms grayscale images of less than 8 to 8 bits,
+changes paletted images to RGB, and adds a full alpha channel if there is
+transparency information in a tRNS chunk.  This is most useful on
+grayscale images with bit depths of 2 or 4 or if there is a multiple-image
+viewing application that wishes to treat all images in the same way.
+
+    if (color_type == PNG_COLOR_TYPE_PALETTE)
+        png_set_palette_to_rgb(png_ptr);
+
+    if (color_type == PNG_COLOR_TYPE_GRAY &&
+        bit_depth < 8) png_set_gray_1_2_4_to_8(png_ptr);
+
+    if (png_get_valid(png_ptr, info_ptr,
+        PNG_INFO_tRNS)) png_set_tRNS_to_alpha(png_ptr);
+
+These three functions are actually aliases for png_set_expand(), added
+in libpng version 1.0.4, with the function names expanded to improve code
+readability.  In some future version they may actually do different
+things.
+
+PNG can have files with 16 bits per channel.  If you only can handle
+8 bits per channel, this will strip the pixels down to 8 bit.
+
+    if (bit_depth == 16)
+        png_set_strip_16(png_ptr);
+
+If, for some reason, you don't need the alpha channel on an image,
+and you want to remove it rather than combining it with the background
+(but the image author certainly had in mind that you *would* combine
+it with the background, so that's what you should probably do):
+
+    if (color_type & PNG_COLOR_MASK_ALPHA)
+        png_set_strip_alpha(png_ptr);
+
+In PNG files, the alpha channel in an image
+is the level of opacity.  If you need the alpha channel in an image to
+be the level of transparency instead of opacity, you can invert the
+alpha channel (or the tRNS chunk data) after it's read, so that 0 is
+fully opaque and 255 (in 8-bit or paletted images) or 65535 (in 16-bit
+images) is fully transparent, with
+
+    png_set_invert_alpha(png_ptr);
+
+PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as
+they can, resulting in, for example, 8 pixels per byte for 1 bit
+files.  This code expands to 1 pixel per byte without changing the
+values of the pixels:
+
+    if (bit_depth < 8)
+        png_set_packing(png_ptr);
+
+PNG files have possible bit depths of 1, 2, 4, 8, and 16.  All pixels
+stored in a PNG image have been "scaled" or "shifted" up to the next
+higher possible bit depth (e.g. from 5 bits/sample in the range [0,31] to
+8 bits/sample in the range [0, 255]).  However, it is also possible to
+convert the PNG pixel data back to the original bit depth of the image.
+This call reduces the pixels back down to the original bit depth:
+
+    png_color_8p sig_bit;
+
+    if (png_get_sBIT(png_ptr, info_ptr, &sig_bit))
+        png_set_shift(png_ptr, sig_bit);
+
+PNG files store 3-color pixels in red, green, blue order.  This code
+changes the storage of the pixels to blue, green, red:
+
+    if (color_type == PNG_COLOR_TYPE_RGB ||
+        color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+        png_set_bgr(png_ptr);
+
+PNG files store RGB pixels packed into 3 or 6 bytes. This code expands them
+into 4 or 8 bytes for windowing systems that need them in this format:
+
+    if (color_type == PNG_COLOR_TYPE_RGB)
+        png_set_filler(png_ptr, filler, PNG_FILLER_BEFORE);
+
+where "filler" is the 8 or 16-bit number to fill with, and the location is
+either PNG_FILLER_BEFORE or PNG_FILLER_AFTER, depending upon whether
+you want the filler before the RGB or after.  This transformation
+does not affect images that already have full alpha channels.  To add an
+opaque alpha channel, use filler=0xff or 0xffff and PNG_FILLER_AFTER which
+will generate RGBA pixels.
+
+Note that png_set_filler() does not change the color type.  If you want
+to do that, you can add a true alpha channel with
+
+    if (color_type == PNG_COLOR_TYPE_RGB ||
+           color_type == PNG_COLOR_TYPE_GRAY)
+    png_set_add_alpha(png_ptr, filler, PNG_FILLER_AFTER);
+
+where "filler" contains the alpha value to assign to each pixel.
+This function was added in libpng-1.2.7.
+
+If you are reading an image with an alpha channel, and you need the
+data as ARGB instead of the normal PNG format RGBA:
+
+    if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+        png_set_swap_alpha(png_ptr);
+
+For some uses, you may want a grayscale image to be represented as
+RGB.  This code will do that conversion:
+
+    if (color_type == PNG_COLOR_TYPE_GRAY ||
+        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+          png_set_gray_to_rgb(png_ptr);
+
+Conversely, you can convert an RGB or RGBA image to grayscale or grayscale
+with alpha.
+
+    if (color_type == PNG_COLOR_TYPE_RGB ||
+        color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+          png_set_rgb_to_gray_fixed(png_ptr, error_action,
+             int red_weight, int green_weight);
+
+    error_action = 1: silently do the conversion
+    error_action = 2: issue a warning if the original
+                      image has any pixel where
+                      red != green or red != blue
+    error_action = 3: issue an error and abort the
+                      conversion if the original
+                      image has any pixel where
+                      red != green or red != blue
+
+    red_weight:       weight of red component times 100000
+    green_weight:     weight of green component times 100000
+                      If either weight is negative, default
+                      weights (21268, 71514) are used.
+
+If you have set error_action = 1 or 2, you can
+later check whether the image really was gray, after processing
+the image rows, with the png_get_rgb_to_gray_status(png_ptr) function.
+It will return a png_byte that is zero if the image was gray or
+1 if there were any non-gray pixels.  bKGD and sBIT data
+will be silently converted to grayscale, using the green channel
+data, regardless of the error_action setting.
+
+With red_weight+green_weight<=100000,
+the normalized graylevel is computed:
+
+    int rw = red_weight * 65536;
+    int gw = green_weight * 65536;
+    int bw = 65536 - (rw + gw);
+    gray = (rw*red + gw*green + bw*blue)/65536;
+
+The default values approximate those recommended in the Charles
+Poynton's Color FAQ, <http://www.inforamp.net/~poynton/>
+Copyright (c) 1998-01-04 Charles Poynton <poynton at inforamp.net>
+
+    Y = 0.212671 * R + 0.715160 * G + 0.072169 * B
+
+Libpng approximates this with
+
+    Y = 0.21268 * R    + 0.7151 * G    + 0.07217 * B
+
+which can be expressed with integers as
+
+    Y = (6969 * R + 23434 * G + 2365 * B)/32768
+
+The calculation is done in a linear colorspace, if the image gamma
+is known.
+
+If you have a grayscale and you are using png_set_expand_depth(),
+png_set_expand(), or png_set_gray_to_rgb to change to truecolor or to
+a higher bit-depth, you must either supply the background color as a gray
+value at the original file bit-depth (need_expand = 1) or else supply the
+background color as an RGB triplet at the final, expanded bit depth
+(need_expand = 0).  Similarly, if you are reading a paletted image, you
+must either supply the background color as a palette index (need_expand = 1)
+or as an RGB triplet that may or may not be in the palette (need_expand = 0).
+
+    png_color_16 my_background;
+    png_color_16p image_background;
+
+    if (png_get_bKGD(png_ptr, info_ptr, &image_background))
+        png_set_background(png_ptr, image_background,
+          PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
+    else
+        png_set_background(png_ptr, &my_background,
+          PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
+
+The png_set_background() function tells libpng to composite images
+with alpha or simple transparency against the supplied background
+color.  If the PNG file contains a bKGD chunk (PNG_INFO_bKGD valid),
+you may use this color, or supply another color more suitable for
+the current display (e.g., the background color from a web page).  You
+need to tell libpng whether the color is in the gamma space of the
+display (PNG_BACKGROUND_GAMMA_SCREEN for colors you supply), the file
+(PNG_BACKGROUND_GAMMA_FILE for colors from the bKGD chunk), or one
+that is neither of these gammas (PNG_BACKGROUND_GAMMA_UNIQUE - I don't
+know why anyone would use this, but it's here).
+
+To properly display PNG images on any kind of system, the application needs
+to know what the display gamma is.  Ideally, the user will know this, and
+the application will allow them to set it.  One method of allowing the user
+to set the display gamma separately for each system is to check for a
+SCREEN_GAMMA or DISPLAY_GAMMA environment variable, which will hopefully be
+correctly set.
+
+Note that display_gamma is the overall gamma correction required to produce
+pleasing results, which depends on the lighting conditions in the surrounding
+environment.  In a dim or brightly lit room, no compensation other than
+the physical gamma exponent of the monitor is needed, while in a dark room
+a slightly smaller exponent is better.
+
+   double gamma, screen_gamma;
+
+   if (/* We have a user-defined screen
+       gamma value */)
+   {
+      screen_gamma = user_defined_screen_gamma;
+   }
+   /* One way that applications can share the same
+      screen gamma value */
+   else if ((gamma_str = getenv("SCREEN_GAMMA"))
+      != NULL)
+   {
+      screen_gamma = (double)atof(gamma_str);
+   }
+   /* If we don't have another value */
+   else
+   {
+      screen_gamma = 2.2; /* A good guess for a
+           PC monitor in a bright office or a dim room */
+      screen_gamma = 2.0; /* A good guess for a
+           PC monitor in a dark room */
+      screen_gamma = 1.7 or 1.0;  /* A good
+           guess for Mac systems */
+   }
+
+The png_set_gamma() function handles gamma transformations of the data.
+Pass both the file gamma and the current screen_gamma.  If the file does
+not have a gamma value, you can pass one anyway if you have an idea what
+it is (usually 0.45455 is a good guess for GIF images on PCs).  Note
+that file gammas are inverted from screen gammas.  See the discussions
+on gamma in the PNG specification for an excellent description of what
+gamma is, and why all applications should support it.  It is strongly
+recommended that PNG viewers support gamma correction.
+
+   if (png_get_gAMA(png_ptr, info_ptr, &gamma))
+      png_set_gamma(png_ptr, screen_gamma, gamma);
+   else
+      png_set_gamma(png_ptr, screen_gamma, 0.45455);
+
+If you need to reduce an RGB file to a paletted file, or if a paletted
+file has more entries then will fit on your screen, png_set_dither()
+will do that.  Note that this is a simple match dither that merely
+finds the closest color available.  This should work fairly well with
+optimized palettes, and fairly badly with linear color cubes.  If you
+pass a palette that is larger then maximum_colors, the file will
+reduce the number of colors in the palette so it will fit into
+maximum_colors.  If there is a histogram, it will use it to make
+more intelligent choices when reducing the palette.  If there is no
+histogram, it may not do as good a job.
+
+   if (color_type & PNG_COLOR_MASK_COLOR)
+   {
+      if (png_get_valid(png_ptr, info_ptr,
+         PNG_INFO_PLTE))
+      {
+         png_uint_16p histogram = NULL;
+
+         png_get_hIST(png_ptr, info_ptr,
+            &histogram);
+         png_set_dither(png_ptr, palette, num_palette,
+            max_screen_colors, histogram, 1);
+      }
+      else
+      {
+         png_color std_color_cube[MAX_SCREEN_COLORS] =
+            { ... colors ... };
+
+         png_set_dither(png_ptr, std_color_cube,
+            MAX_SCREEN_COLORS, MAX_SCREEN_COLORS,
+            NULL,0);
+      }
+   }
+
+PNG files describe monochrome as black being zero and white being one.
+The following code will reverse this (make black be one and white be
+zero):
+
+   if (bit_depth == 1 && color_type == PNG_COLOR_TYPE_GRAY)
+      png_set_invert_mono(png_ptr);
+
+This function can also be used to invert grayscale and gray-alpha images:
+
+   if (color_type == PNG_COLOR_TYPE_GRAY ||
+        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      png_set_invert_mono(png_ptr);
+
+PNG files store 16 bit pixels in network byte order (big-endian,
+ie. most significant bits first).  This code changes the storage to the
+other way (little-endian, i.e. least significant bits first, the
+way PCs store them):
+
+    if (bit_depth == 16)
+        png_set_swap(png_ptr);
+
+If you are using packed-pixel images (1, 2, or 4 bits/pixel), and you
+need to change the order the pixels are packed into bytes, you can use:
+
+    if (bit_depth < 8)
+       png_set_packswap(png_ptr);
+
+Finally, you can write your own transformation function if none of
+the existing ones meets your needs.  This is done by setting a callback
+with
+
+    png_set_read_user_transform_fn(png_ptr,
+       read_transform_fn);
+
+You must supply the function
+
+    void read_transform_fn(png_ptr ptr, row_info_ptr
+       row_info, png_bytep data)
+
+See pngtest.c for a working example.  Your function will be called
+after all of the other transformations have been processed.
+
+You can also set up a pointer to a user structure for use by your
+callback function, and you can inform libpng that your transform
+function will change the number of channels or bit depth with the
+function
+
+    png_set_user_transform_info(png_ptr, user_ptr,
+       user_depth, user_channels);
+
+The user's application, not libpng, is responsible for allocating and
+freeing any memory required for the user structure.
+
+You can retrieve the pointer via the function
+png_get_user_transform_ptr().  For example:
+
+    voidp read_user_transform_ptr =
+       png_get_user_transform_ptr(png_ptr);
+
+The last thing to handle is interlacing; this is covered in detail below,
+but you must call the function here if you want libpng to handle expansion
+of the interlaced image.
+
+    number_of_passes = png_set_interlace_handling(png_ptr);
+
+After setting the transformations, libpng can update your png_info
+structure to reflect any transformations you've requested with this
+call.  This is most useful to update the info structure's rowbytes
+field so you can use it to allocate your image memory.  This function
+will also update your palette with the correct screen_gamma and
+background if these have been given with the calls above.
+
+    png_read_update_info(png_ptr, info_ptr);
+
+After you call png_read_update_info(), you can allocate any
+memory you need to hold the image.  The row data is simply
+raw byte data for all forms of images.  As the actual allocation
+varies among applications, no example will be given.  If you
+are allocating one large chunk, you will need to build an
+array of pointers to each row, as it will be needed for some
+of the functions below.
+
+.SS Reading image data
+
+After you've allocated memory, you can read the image data.
+The simplest way to do this is in one function call.  If you are
+allocating enough memory to hold the whole image, you can just
+call png_read_image() and libpng will read in all the image data
+and put it in the memory area supplied.  You will need to pass in
+an array of pointers to each row.
+
+This function automatically handles interlacing, so you don't need
+to call png_set_interlace_handling() or call this function multiple
+times, or any of that other stuff necessary with png_read_rows().
+
+   png_read_image(png_ptr, row_pointers);
+
+where row_pointers is:
+
+   png_bytep row_pointers[height];
+
+You can point to void or char or whatever you use for pixels.
+
+If you don't want to read in the whole image at once, you can
+use png_read_rows() instead.  If there is no interlacing (check
+interlace_type == PNG_INTERLACE_NONE), this is simple:
+
+    png_read_rows(png_ptr, row_pointers, NULL,
+       number_of_rows);
+
+where row_pointers is the same as in the png_read_image() call.
+
+If you are doing this just one row at a time, you can do this with
+a single row_pointer instead of an array of row_pointers:
+
+    png_bytep row_pointer = row;
+    png_read_row(png_ptr, row_pointer, NULL);
+
+If the file is interlaced (interlace_type != 0 in the IHDR chunk), things
+get somewhat harder.  The only current (PNG Specification version 1.2)
+interlacing type for PNG is (interlace_type == PNG_INTERLACE_ADAM7)
+is a somewhat complicated 2D interlace scheme, known as Adam7, that
+breaks down an image into seven smaller images of varying size, based
+on an 8x8 grid.
+
+libpng can fill out those images or it can give them to you "as is".
+If you want them filled out, there are two ways to do that.  The one
+mentioned in the PNG specification is to expand each pixel to cover
+those pixels that have not been read yet (the "rectangle" method).
+This results in a blocky image for the first pass, which gradually
+smooths out as more pixels are read.  The other method is the "sparkle"
+method, where pixels are drawn only in their final locations, with the
+rest of the image remaining whatever colors they were initialized to
+before the start of the read.  The first method usually looks better,
+but tends to be slower, as there are more pixels to put in the rows.
+
+If you don't want libpng to handle the interlacing details, just call
+png_read_rows() seven times to read in all seven images.  Each of the
+images is a valid image by itself, or they can all be combined on an
+8x8 grid to form a single image (although if you intend to combine them
+you would be far better off using the libpng interlace handling).
+
+The first pass will return an image 1/8 as wide as the entire image
+(every 8th column starting in column 0) and 1/8 as high as the original
+(every 8th row starting in row 0), the second will be 1/8 as wide
+(starting in column 4) and 1/8 as high (also starting in row 0).  The
+third pass will be 1/4 as wide (every 4th pixel starting in column 0) and
+1/8 as high (every 8th row starting in row 4), and the fourth pass will
+be 1/4 as wide and 1/4 as high (every 4th column starting in column 2,
+and every 4th row starting in row 0).  The fifth pass will return an
+image 1/2 as wide, and 1/4 as high (starting at column 0 and row 2),
+while the sixth pass will be 1/2 as wide and 1/2 as high as the original
+(starting in column 1 and row 0).  The seventh and final pass will be as
+wide as the original, and 1/2 as high, containing all of the odd
+numbered scanlines.  Phew!
+
+If you want libpng to expand the images, call this before calling
+png_start_read_image() or png_read_update_info():
+
+    if (interlace_type == PNG_INTERLACE_ADAM7)
+        number_of_passes
+           = png_set_interlace_handling(png_ptr);
+
+This will return the number of passes needed.  Currently, this
+is seven, but may change if another interlace type is added.
+This function can be called even if the file is not interlaced,
+where it will return one pass.
+
+If you are not going to display the image after each pass, but are
+going to wait until the entire image is read in, use the sparkle
+effect.  This effect is faster and the end result of either method
+is exactly the same.  If you are planning on displaying the image
+after each pass, the "rectangle" effect is generally considered the
+better looking one.
+
+If you only want the "sparkle" effect, just call png_read_rows() as
+normal, with the third parameter NULL.  Make sure you make pass over
+the image number_of_passes times, and you don't change the data in the
+rows between calls.  You can change the locations of the data, just
+not the data.  Each pass only writes the pixels appropriate for that
+pass, and assumes the data from previous passes is still valid.
+
+    png_read_rows(png_ptr, row_pointers, NULL,
+       number_of_rows);
+
+If you only want the first effect (the rectangles), do the same as
+before except pass the row buffer in the third parameter, and leave
+the second parameter NULL.
+
+    png_read_rows(png_ptr, NULL, row_pointers,
+       number_of_rows);
+
+.SS Finishing a sequential read
+
+After you are finished reading the image through either the high- or
+low-level interfaces, you can finish reading the file.  If you are
+interested in comments or time, which may be stored either before or
+after the image data, you should pass the separate png_info struct if
+you want to keep the comments from before and after the image
+separate.  If you are not interested, you can pass NULL.
+
+   png_read_end(png_ptr, end_info);
+
+When you are done, you can free all memory allocated by libpng like this:
+
+   png_destroy_read_struct(&png_ptr, &info_ptr,
+       &end_info);
+
+It is also possible to individually free the info_ptr members that
+point to libpng-allocated storage with the following function:
+
+    png_free_data(png_ptr, info_ptr, mask, seq)
+    mask - identifies data to be freed, a mask
+           containing the logical OR of one or
+           more of
+             PNG_FREE_PLTE, PNG_FREE_TRNS,
+             PNG_FREE_HIST, PNG_FREE_ICCP,
+             PNG_FREE_PCAL, PNG_FREE_ROWS,
+             PNG_FREE_SCAL, PNG_FREE_SPLT,
+             PNG_FREE_TEXT, PNG_FREE_UNKN,
+           or simply PNG_FREE_ALL
+    seq  - sequence number of item to be freed
+           (-1 for all items)
+
+This function may be safely called when the relevant storage has
+already been freed, or has not yet been allocated, or was allocated
+by the user and not by libpng,  and will in those
+cases do nothing.  The "seq" parameter is ignored if only one item
+of the selected data type, such as PLTE, is allowed.  If "seq" is not
+-1, and multiple items are allowed for the data type identified in
+the mask, such as text or sPLT, only the n'th item in the structure
+is freed, where n is "seq".
+
+The default behavior is only to free data that was allocated internally
+by libpng.  This can be changed, so that libpng will not free the data,
+or so that it will free data that was allocated by the user with png_malloc()
+or png_zalloc() and passed in via a png_set_*() function, with
+
+    png_data_freer(png_ptr, info_ptr, freer, mask)
+    mask   - which data elements are affected
+             same choices as in png_free_data()
+    freer  - one of
+               PNG_DESTROY_WILL_FREE_DATA
+               PNG_SET_WILL_FREE_DATA
+               PNG_USER_WILL_FREE_DATA
+
+This function only affects data that has already been allocated.
+You can call this function after reading the PNG data but before calling
+any png_set_*() functions, to control whether the user or the png_set_*()
+function is responsible for freeing any existing data that might be present,
+and again after the png_set_*() functions to control whether the user
+or png_destroy_*() is supposed to free the data.  When the user assumes
+responsibility for libpng-allocated data, the application must use
+png_free() to free it, and when the user transfers responsibility to libpng
+for data that the user has allocated, the user must have used png_malloc()
+or png_zalloc() to allocate it.
+
+If you allocated your row_pointers in a single block, as suggested above in
+the description of the high level read interface, you must not transfer
+responsibility for freeing it to the png_set_rows or png_read_destroy function,
+because they would also try to free the individual row_pointers[i].
+
+If you allocated text_ptr.text, text_ptr.lang, and text_ptr.translated_keyword
+separately, do not transfer responsibility for freeing text_ptr to libpng,
+because when libpng fills a png_text structure it combines these members with
+the key member, and png_free_data() will free only text_ptr.key.  Similarly,
+if you transfer responsibility for free'ing text_ptr from libpng to your
+application, your application must not separately free those members.
+
+The png_free_data() function will turn off the "valid" flag for anything
+it frees.  If you need to turn the flag off for a chunk that was freed by your
+application instead of by libpng, you can use
+
+    png_set_invalid(png_ptr, info_ptr, mask);
+    mask - identifies the chunks to be made invalid,
+           containing the logical OR of one or
+           more of
+             PNG_INFO_gAMA, PNG_INFO_sBIT,
+             PNG_INFO_cHRM, PNG_INFO_PLTE,
+             PNG_INFO_tRNS, PNG_INFO_bKGD,
+             PNG_INFO_hIST, PNG_INFO_pHYs,
+             PNG_INFO_oFFs, PNG_INFO_tIME,
+             PNG_INFO_pCAL, PNG_INFO_sRGB,
+             PNG_INFO_iCCP, PNG_INFO_sPLT,
+             PNG_INFO_sCAL, PNG_INFO_IDAT
+
+For a more compact example of reading a PNG image, see the file example.c.
+
+.SS Reading PNG files progressively
+
+The progressive reader is slightly different then the non-progressive
+reader.  Instead of calling png_read_info(), png_read_rows(), and
+png_read_end(), you make one call to png_process_data(), which calls
+callbacks when it has the info, a row, or the end of the image.  You
+set up these callbacks with png_set_progressive_read_fn().  You don't
+have to worry about the input/output functions of libpng, as you are
+giving the library the data directly in png_process_data().  I will
+assume that you have read the section on reading PNG files above,
+so I will only highlight the differences (although I will show
+all of the code).
+
+png_structp png_ptr;
+png_infop info_ptr;
+
+ /*  An example code fragment of how you would
+     initialize the progressive reader in your
+     application. */
+ int
+ initialize_png_reader()
+ {
+    png_ptr = png_create_read_struct
+        (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+         user_error_fn, user_warning_fn);
+    if (!png_ptr)
+        return (ERROR);
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr)
+    {
+        png_destroy_read_struct(&png_ptr, (png_infopp)NULL,
+           (png_infopp)NULL);
+        return (ERROR);
+    }
+
+    if (setjmp(png_jmpbuf(png_ptr)))
+    {
+        png_destroy_read_struct(&png_ptr, &info_ptr,
+           (png_infopp)NULL);
+        return (ERROR);
+    }
+
+    /* This one's new.  You can provide functions
+       to be called when the header info is valid,
+       when each row is completed, and when the image
+       is finished.  If you aren't using all functions,
+       you can specify NULL parameters.  Even when all
+       three functions are NULL, you need to call
+       png_set_progressive_read_fn().  You can use
+       any struct as the user_ptr (cast to a void pointer
+       for the function call), and retrieve the pointer
+       from inside the callbacks using the function
+
+          png_get_progressive_ptr(png_ptr);
+
+       which will return a void pointer, which you have
+       to cast appropriately.
+     */
+    png_set_progressive_read_fn(png_ptr, (void *)user_ptr,
+        info_callback, row_callback, end_callback);
+
+    return 0;
+ }
+
+ /* A code fragment that you call as you receive blocks
+   of data */
+ int
+ process_data(png_bytep buffer, png_uint_32 length)
+ {
+    if (setjmp(png_jmpbuf(png_ptr)))
+    {
+        png_destroy_read_struct(&png_ptr, &info_ptr,
+           (png_infopp)NULL);
+        return (ERROR);
+    }
+
+    /* This one's new also.  Simply give it a chunk
+       of data from the file stream (in order, of
+       course).  On machines with segmented memory
+       models machines, don't give it any more than
+       64K.  The library seems to run fine with sizes
+       of 4K. Although you can give it much less if
+       necessary (I assume you can give it chunks of
+       1 byte, I haven't tried less then 256 bytes
+       yet).  When this function returns, you may
+       want to display any rows that were generated
+       in the row callback if you don't already do
+       so there.
+     */
+    png_process_data(png_ptr, info_ptr, buffer, length);
+    return 0;
+ }
+
+ /* This function is called (as set by
+    png_set_progressive_read_fn() above) when enough data
+    has been supplied so all of the header has been
+    read.
+ */
+ void
+ info_callback(png_structp png_ptr, png_infop info)
+ {
+    /* Do any setup here, including setting any of
+       the transformations mentioned in the Reading
+       PNG files section.  For now, you _must_ call
+       either png_start_read_image() or
+       png_read_update_info() after all the
+       transformations are set (even if you don't set
+       any).  You may start getting rows before
+       png_process_data() returns, so this is your
+       last chance to prepare for that.
+     */
+ }
+
+ /* This function is called when each row of image
+    data is complete */
+ void
+ row_callback(png_structp png_ptr, png_bytep new_row,
+    png_uint_32 row_num, int pass)
+ {
+    /* If the image is interlaced, and you turned
+       on the interlace handler, this function will
+       be called for every row in every pass.  Some
+       of these rows will not be changed from the
+       previous pass.  When the row is not changed,
+       the new_row variable will be NULL.  The rows
+       and passes are called in order, so you don't
+       really need the row_num and pass, but I'm
+       supplying them because it may make your life
+       easier.
+
+       For the non-NULL rows of interlaced images,
+       you must call png_progressive_combine_row()
+       passing in the row and the old row.  You can
+       call this function for NULL rows (it will just
+       return) and for non-interlaced images (it just
+       does the memcpy for you) if it will make the
+       code easier.  Thus, you can just do this for
+       all cases:
+     */
+
+        png_progressive_combine_row(png_ptr, old_row,
+          new_row);
+
+    /* where old_row is what was displayed for
+       previously for the row.  Note that the first
+       pass (pass == 0, really) will completely cover
+       the old row, so the rows do not have to be
+       initialized.  After the first pass (and only
+       for interlaced images), you will have to pass
+       the current row, and the function will combine
+       the old row and the new row.
+    */
+ }
+
+ void
+ end_callback(png_structp png_ptr, png_infop info)
+ {
+    /* This function is called after the whole image
+       has been read, including any chunks after the
+       image (up to and including the IEND).  You
+       will usually have the same info chunk as you
+       had in the header, although some data may have
+       been added to the comments and time fields.
+
+       Most people won't do much here, perhaps setting
+       a flag that marks the image as finished.
+     */
+ }
+
+
+
+.SH IV. Writing
+
+Much of this is very similar to reading.  However, everything of
+importance is repeated here, so you won't have to constantly look
+back up in the reading section to understand writing.
+
+.SS Setup
+
+You will want to do the I/O initialization before you get into libpng,
+so if it doesn't work, you don't have anything to undo. If you are not
+using the standard I/O functions, you will need to replace them with
+custom writing functions.  See the discussion under Customizing libpng.
+
+    FILE *fp = fopen(file_name, "wb");
+    if (!fp)
+    {
+       return (ERROR);
+    }
+
+Next, png_struct and png_info need to be allocated and initialized.
+As these can be both relatively large, you may not want to store these
+on the stack, unless you have stack space to spare.  Of course, you
+will want to check if they return NULL.  If you are also reading,
+you won't want to name your read structure and your write structure
+both "png_ptr"; you can call them anything you like, such as
+"read_ptr" and "write_ptr".  Look at pngtest.c, for example.
+
+    png_structp png_ptr = png_create_write_struct
+       (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+        user_error_fn, user_warning_fn);
+    if (!png_ptr)
+       return (ERROR);
+
+    png_infop info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr)
+    {
+       png_destroy_write_struct(&png_ptr,
+         (png_infopp)NULL);
+       return (ERROR);
+    }
+
+If you want to use your own memory allocation routines,
+define PNG_USER_MEM_SUPPORTED and use
+png_create_write_struct_2() instead of png_create_write_struct():
+
+    png_structp png_ptr = png_create_write_struct_2
+       (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+        user_error_fn, user_warning_fn, (png_voidp)
+        user_mem_ptr, user_malloc_fn, user_free_fn);
+
+After you have these structures, you will need to set up the
+error handling.  When libpng encounters an error, it expects to
+longjmp() back to your routine.  Therefore, you will need to call
+setjmp() and pass the png_jmpbuf(png_ptr).  If you
+write the file from different routines, you will need to update
+the png_jmpbuf(png_ptr) every time you enter a new routine that will
+call a png_*() function.  See your documentation of setjmp/longjmp
+for your compiler for more information on setjmp/longjmp.  See
+the discussion on libpng error handling in the Customizing Libpng
+section below for more information on the libpng error handling.
+
+    if (setjmp(png_jmpbuf(png_ptr)))
+    {
+       png_destroy_write_struct(&png_ptr, &info_ptr);
+       fclose(fp);
+       return (ERROR);
+    }
+    ...
+    return;
+
+If you would rather avoid the complexity of setjmp/longjmp issues,
+you can compile libpng with PNG_SETJMP_NOT_SUPPORTED, in which case
+errors will result in a call to PNG_ABORT() which defaults to abort().
+
+Now you need to set up the output code.  The default for libpng is to
+use the C function fwrite().  If you use this, you will need to pass a
+valid FILE * in the function png_init_io().  Be sure that the file is
+opened in binary mode.  Again, if you wish to handle writing data in
+another way, see the discussion on libpng I/O handling in the Customizing
+Libpng section below.
+
+    png_init_io(png_ptr, fp);
+
+.SS Write callbacks
+
+At this point, you can set up a callback function that will be
+called after each row has been written, which you can use to control
+a progress meter or the like.  It's demonstrated in pngtest.c.
+You must supply a function
+
+    void write_row_callback(png_ptr, png_uint_32 row,
+       int pass);
+    {
+      /* put your code here */
+    }
+
+(You can give it another name that you like instead of "write_row_callback")
+
+To inform libpng about your function, use
+
+    png_set_write_status_fn(png_ptr, write_row_callback);
+
+You now have the option of modifying how the compression library will
+run.  The following functions are mainly for testing, but may be useful
+in some cases, like if you need to write PNG files extremely fast and
+are willing to give up some compression, or if you want to get the
+maximum possible compression at the expense of slower writing.  If you
+have no special needs in this area, let the library do what it wants by
+not calling this function at all, as it has been tuned to deliver a good
+speed/compression ratio. The second parameter to png_set_filter() is
+the filter method, for which the only valid values are 0 (as of the
+July 1999 PNG specification, version 1.2) or 64 (if you are writing
+a PNG datastream that is to be embedded in a MNG datastream).  The third
+parameter is a flag that indicates which filter type(s) are to be tested
+for each scanline.  See the PNG specification for details on the specific filter
+types.
+
+
+    /* turn on or off filtering, and/or choose
+       specific filters.  You can use either a single
+       PNG_FILTER_VALUE_NAME or the logical OR of one
+       or more PNG_FILTER_NAME masks. */
+    png_set_filter(png_ptr, 0,
+       PNG_FILTER_NONE  | PNG_FILTER_VALUE_NONE |
+       PNG_FILTER_SUB   | PNG_FILTER_VALUE_SUB  |
+       PNG_FILTER_UP    | PNG_FILTER_VALUE_UP   |
+       PNG_FILTER_AVE   | PNG_FILTER_VALUE_AVE  |
+       PNG_FILTER_PAETH | PNG_FILTER_VALUE_PAETH|
+       PNG_ALL_FILTERS);
+
+If an application
+wants to start and stop using particular filters during compression,
+it should start out with all of the filters (to ensure that the previous
+row of pixels will be stored in case it's needed later), and then add
+and remove them after the start of compression.
+
+If you are writing a PNG datastream that is to be embedded in a MNG
+datastream, the second parameter can be either 0 or 64.
+
+The png_set_compression_*() functions interface to the zlib compression
+library, and should mostly be ignored unless you really know what you are
+doing.  The only generally useful call is png_set_compression_level()
+which changes how much time zlib spends on trying to compress the image
+data.  See the Compression Library (zlib.h and algorithm.txt, distributed
+with zlib) for details on the compression levels.
+
+    /* set the zlib compression level */
+    png_set_compression_level(png_ptr,
+        Z_BEST_COMPRESSION);
+
+    /* set other zlib parameters */
+    png_set_compression_mem_level(png_ptr, 8);
+    png_set_compression_strategy(png_ptr,
+        Z_DEFAULT_STRATEGY);
+    png_set_compression_window_bits(png_ptr, 15);
+    png_set_compression_method(png_ptr, 8);
+    png_set_compression_buffer_size(png_ptr, 8192)
+
+extern PNG_EXPORT(void,png_set_zbuf_size)
+
+.SS Setting the contents of info for output
+
+You now need to fill in the png_info structure with all the data you
+wish to write before the actual image.  Note that the only thing you
+are allowed to write after the image is the text chunks and the time
+chunk (as of PNG Specification 1.2, anyway).  See png_write_end() and
+the latest PNG specification for more information on that.  If you
+wish to write them before the image, fill them in now, and flag that
+data as being valid.  If you want to wait until after the data, don't
+fill them until png_write_end().  For all the fields in png_info and
+their data types, see png.h.  For explanations of what the fields
+contain, see the PNG specification.
+
+Some of the more important parts of the png_info are:
+
+    png_set_IHDR(png_ptr, info_ptr, width, height,
+       bit_depth, color_type, interlace_type,
+       compression_type, filter_method)
+    width          - holds the width of the image
+                     in pixels (up to 2^31).
+    height         - holds the height of the image
+                     in pixels (up to 2^31).
+    bit_depth      - holds the bit depth of one of the
+                     image channels.
+                     (valid values are 1, 2, 4, 8, 16
+                     and depend also on the
+                     color_type.  See also significant
+                     bits (sBIT) below).
+    color_type     - describes which color/alpha
+                     channels are present.
+                     PNG_COLOR_TYPE_GRAY
+                        (bit depths 1, 2, 4, 8, 16)
+                     PNG_COLOR_TYPE_GRAY_ALPHA
+                        (bit depths 8, 16)
+                     PNG_COLOR_TYPE_PALETTE
+                        (bit depths 1, 2, 4, 8)
+                     PNG_COLOR_TYPE_RGB
+                        (bit_depths 8, 16)
+                     PNG_COLOR_TYPE_RGB_ALPHA
+                        (bit_depths 8, 16)
+
+                     PNG_COLOR_MASK_PALETTE
+                     PNG_COLOR_MASK_COLOR
+                     PNG_COLOR_MASK_ALPHA
+
+    interlace_type - PNG_INTERLACE_NONE or
+                     PNG_INTERLACE_ADAM7
+    compression_type - (must be
+                     PNG_COMPRESSION_TYPE_DEFAULT)
+    filter_method  - (must be PNG_FILTER_TYPE_DEFAULT
+                     or, if you are writing a PNG to
+                     be embedded in a MNG datastream,
+                     can also be
+                     PNG_INTRAPIXEL_DIFFERENCING)
+
+    png_set_PLTE(png_ptr, info_ptr, palette,
+       num_palette);
+    palette        - the palette for the file
+                     (array of png_color)
+    num_palette    - number of entries in the palette
+
+    png_set_gAMA(png_ptr, info_ptr, gamma);
+    gamma          - the gamma the image was created
+                     at (PNG_INFO_gAMA)
+
+    png_set_sRGB(png_ptr, info_ptr, srgb_intent);
+    srgb_intent    - the rendering intent
+                     (PNG_INFO_sRGB) The presence of
+                     the sRGB chunk means that the pixel
+                     data is in the sRGB color space.
+                     This chunk also implies specific
+                     values of gAMA and cHRM.  Rendering
+                     intent is the CSS-1 property that
+                     has been defined by the International
+                     Color Consortium
+                     (http://www.color.org).
+                     It can be one of
+                     PNG_sRGB_INTENT_SATURATION,
+                     PNG_sRGB_INTENT_PERCEPTUAL,
+                     PNG_sRGB_INTENT_ABSOLUTE, or
+                     PNG_sRGB_INTENT_RELATIVE.
+
+
+    png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr,
+       srgb_intent);
+    srgb_intent    - the rendering intent
+                     (PNG_INFO_sRGB) The presence of the
+                     sRGB chunk means that the pixel
+                     data is in the sRGB color space.
+                     This function also causes gAMA and
+                     cHRM chunks with the specific values
+                     that are consistent with sRGB to be
+                     written.
+
+    png_set_iCCP(png_ptr, info_ptr, name, compression_type,
+                      profile, proflen);
+    name            - The profile name.
+    compression     - The compression type; always
+                      PNG_COMPRESSION_TYPE_BASE for PNG 1.0.
+                      You may give NULL to this argument to
+                      ignore it.
+    profile         - International Color Consortium color
+                      profile data. May contain NULs.
+    proflen         - length of profile data in bytes.
+
+    png_set_sBIT(png_ptr, info_ptr, sig_bit);
+    sig_bit        - the number of significant bits for
+                     (PNG_INFO_sBIT) each of the gray, red,
+                     green, and blue channels, whichever are
+                     appropriate for the given color type
+                     (png_color_16)
+
+    png_set_tRNS(png_ptr, info_ptr, trans, num_trans,
+       trans_values);
+    trans          - array of transparent entries for
+                     palette (PNG_INFO_tRNS)
+    trans_values   - graylevel or color sample values of
+                     the single transparent color for
+                     non-paletted images (PNG_INFO_tRNS)
+    num_trans      - number of transparent entries
+                     (PNG_INFO_tRNS)
+
+    png_set_hIST(png_ptr, info_ptr, hist);
+                    (PNG_INFO_hIST)
+    hist           - histogram of palette (array of
+                     png_uint_16)
+
+    png_set_tIME(png_ptr, info_ptr, mod_time);
+    mod_time       - time image was last modified
+                     (PNG_VALID_tIME)
+
+    png_set_bKGD(png_ptr, info_ptr, background);
+    background     - background color (PNG_VALID_bKGD)
+
+    png_set_text(png_ptr, info_ptr, text_ptr, num_text);
+    text_ptr       - array of png_text holding image
+                     comments
+    text_ptr[i].compression - type of compression used
+                 on "text" PNG_TEXT_COMPRESSION_NONE
+                           PNG_TEXT_COMPRESSION_zTXt
+                           PNG_ITXT_COMPRESSION_NONE
+                           PNG_ITXT_COMPRESSION_zTXt
+    text_ptr[i].key   - keyword for comment.  Must contain
+                 1-79 characters.
+    text_ptr[i].text  - text comments for current
+                         keyword.  Can be NULL or empty.
+    text_ptr[i].text_length - length of text string,
+                 after decompression, 0 for iTXt
+    text_ptr[i].itxt_length - length of itxt string,
+                 after decompression, 0 for tEXt/zTXt
+    text_ptr[i].lang  - language of comment (NULL or
+                         empty for unknown).
+    text_ptr[i].translated_keyword  - keyword in UTF-8 (NULL
+                         or empty for unknown).
+    num_text       - number of comments
+
+    png_set_sPLT(png_ptr, info_ptr, &palette_ptr,
+       num_spalettes);
+    palette_ptr    - array of png_sPLT_struct structures
+                     to be added to the list of palettes
+                     in the info structure.
+    num_spalettes  - number of palette structures to be
+                     added.
+
+    png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y,
+        unit_type);
+    offset_x  - positive offset from the left
+                     edge of the screen
+    offset_y  - positive offset from the top
+                     edge of the screen
+    unit_type - PNG_OFFSET_PIXEL, PNG_OFFSET_MICROMETER
+
+    png_set_pHYs(png_ptr, info_ptr, res_x, res_y,
+        unit_type);
+    res_x       - pixels/unit physical resolution
+                  in x direction
+    res_y       - pixels/unit physical resolution
+                  in y direction
+    unit_type   - PNG_RESOLUTION_UNKNOWN,
+                  PNG_RESOLUTION_METER
+
+    png_set_sCAL(png_ptr, info_ptr, unit, width, height)
+    unit        - physical scale units (an integer)
+    width       - width of a pixel in physical scale units
+    height      - height of a pixel in physical scale units
+                  (width and height are doubles)
+
+    png_set_sCAL_s(png_ptr, info_ptr, unit, width, height)
+    unit        - physical scale units (an integer)
+    width       - width of a pixel in physical scale units
+    height      - height of a pixel in physical scale units
+                 (width and height are strings like "2.54")
+
+    png_set_unknown_chunks(png_ptr, info_ptr, &unknowns,
+       num_unknowns)
+    unknowns          - array of png_unknown_chunk
+                        structures holding unknown chunks
+    unknowns[i].name  - name of unknown chunk
+    unknowns[i].data  - data of unknown chunk
+    unknowns[i].size  - size of unknown chunk's data
+    unknowns[i].location - position to write chunk in file
+                           0: do not write chunk
+                           PNG_HAVE_IHDR: before PLTE
+                           PNG_HAVE_PLTE: before IDAT
+                           PNG_AFTER_IDAT: after IDAT
+
+The "location" member is set automatically according to
+what part of the output file has already been written.
+You can change its value after calling png_set_unknown_chunks()
+as demonstrated in pngtest.c.  Within each of the "locations",
+the chunks are sequenced according to their position in the
+structure (that is, the value of "i", which is the order in which
+the chunk was either read from the input file or defined with
+png_set_unknown_chunks).
+
+A quick word about text and num_text.  text is an array of png_text
+structures.  num_text is the number of valid structures in the array.
+Each png_text structure holds a language code, a keyword, a text value,
+and a compression type.
+
+The compression types have the same valid numbers as the compression
+types of the image data.  Currently, the only valid number is zero.
+However, you can store text either compressed or uncompressed, unlike
+images, which always have to be compressed.  So if you don't want the
+text compressed, set the compression type to PNG_TEXT_COMPRESSION_NONE.
+Because tEXt and zTXt chunks don't have a language field, if you
+specify PNG_TEXT_COMPRESSION_NONE or PNG_TEXT_COMPRESSION_zTXt
+any language code or translated keyword will not be written out.
+
+Until text gets around 1000 bytes, it is not worth compressing it.
+After the text has been written out to the file, the compression type
+is set to PNG_TEXT_COMPRESSION_NONE_WR or PNG_TEXT_COMPRESSION_zTXt_WR,
+so that it isn't written out again at the end (in case you are calling
+png_write_end() with the same struct.
+
+The keywords that are given in the PNG Specification are:
+
+    Title            Short (one line) title or
+                     caption for image
+    Author           Name of image's creator
+    Description      Description of image (possibly long)
+    Copyright        Copyright notice
+    Creation Time    Time of original image creation
+                     (usually RFC 1123 format, see below)
+    Software         Software used to create the image
+    Disclaimer       Legal disclaimer
+    Warning          Warning of nature of content
+    Source           Device used to create the image
+    Comment          Miscellaneous comment; conversion
+                     from other image format
+
+The keyword-text pairs work like this.  Keywords should be short
+simple descriptions of what the comment is about.  Some typical
+keywords are found in the PNG specification, as is some recommendations
+on keywords.  You can repeat keywords in a file.  You can even write
+some text before the image and some after.  For example, you may want
+to put a description of the image before the image, but leave the
+disclaimer until after, so viewers working over modem connections
+don't have to wait for the disclaimer to go over the modem before
+they start seeing the image.  Finally, keywords should be full
+words, not abbreviations.  Keywords and text are in the ISO 8859-1
+(Latin-1) character set (a superset of regular ASCII) and can not
+contain NUL characters, and should not contain control or other
+unprintable characters.  To make the comments widely readable, stick
+with basic ASCII, and avoid machine specific character set extensions
+like the IBM-PC character set.  The keyword must be present, but
+you can leave off the text string on non-compressed pairs.
+Compressed pairs must have a text string, as only the text string
+is compressed anyway, so the compression would be meaningless.
+
+PNG supports modification time via the png_time structure.  Two
+conversion routines are provided, png_convert_from_time_t() for
+time_t and png_convert_from_struct_tm() for struct tm.  The
+time_t routine uses gmtime().  You don't have to use either of
+these, but if you wish to fill in the png_time structure directly,
+you should provide the time in universal time (GMT) if possible
+instead of your local time.  Note that the year number is the full
+year (e.g. 1998, rather than 98 - PNG is year 2000 compliant!), and
+that months start with 1.
+
+If you want to store the time of the original image creation, you should
+use a plain tEXt chunk with the "Creation Time" keyword.  This is
+necessary because the "creation time" of a PNG image is somewhat vague,
+depending on whether you mean the PNG file, the time the image was
+created in a non-PNG format, a still photo from which the image was
+scanned, or possibly the subject matter itself.  In order to facilitate
+machine-readable dates, it is recommended that the "Creation Time"
+tEXt chunk use RFC 1123 format dates (e.g. "22 May 1997 18:07:10 GMT"),
+although this isn't a requirement.  Unlike the tIME chunk, the
+"Creation Time" tEXt chunk is not expected to be automatically changed
+by the software.  To facilitate the use of RFC 1123 dates, a function
+png_convert_to_rfc1123(png_timep) is provided to convert from PNG
+time to an RFC 1123 format string.
+
+.SS Writing unknown chunks
+
+You can use the png_set_unknown_chunks function to queue up chunks
+for writing.  You give it a chunk name, raw data, and a size; that's
+all there is to it.  The chunks will be written by the next following
+png_write_info_before_PLTE, png_write_info, or png_write_end function.
+Any chunks previously read into the info structure's unknown-chunk
+list will also be written out in a sequence that satisfies the PNG
+specification's ordering rules.
+
+.SS The high-level write interface
+
+At this point there are two ways to proceed; through the high-level
+write interface, or through a sequence of low-level write operations.
+You can use the high-level interface if your image data is present
+in the info structure.  All defined output
+transformations are permitted, enabled by the following masks.
+
+    PNG_TRANSFORM_IDENTITY      No transformation
+    PNG_TRANSFORM_PACKING       Pack 1, 2 and 4-bit samples
+    PNG_TRANSFORM_PACKSWAP      Change order of packed
+                                pixels to LSB first
+    PNG_TRANSFORM_INVERT_MONO   Invert monochrome images
+    PNG_TRANSFORM_SHIFT         Normalize pixels to the
+                                sBIT depth
+    PNG_TRANSFORM_BGR           Flip RGB to BGR, RGBA
+                                to BGRA
+    PNG_TRANSFORM_SWAP_ALPHA    Flip RGBA to ARGB or GA
+                                to AG
+    PNG_TRANSFORM_INVERT_ALPHA  Change alpha from opacity
+                                to transparency
+    PNG_TRANSFORM_SWAP_ENDIAN   Byte-swap 16-bit samples
+    PNG_TRANSFORM_STRIP_FILLER  Strip out filler bytes.
+
+If you have valid image data in the info structure (you can use
+png_set_rows() to put image data in the info structure), simply do this:
+
+    png_write_png(png_ptr, info_ptr, png_transforms, NULL)
+
+where png_transforms is an integer containing the logical OR of some set of
+transformation flags.  This call is equivalent to png_write_info(),
+followed the set of transformations indicated by the transform mask,
+then png_write_image(), and finally png_write_end().
+
+(The final parameter of this call is not yet used.  Someday it might point
+to transformation parameters required by some future output transform.)
+
+You must use png_transforms and not call any png_set_transform() functions
+when you use png_write_png().
+
+.SS The low-level write interface
+
+If you are going the low-level route instead, you are now ready to
+write all the file information up to the actual image data.  You do
+this with a call to png_write_info().
+
+    png_write_info(png_ptr, info_ptr);
+
+Note that there is one transformation you may need to do before
+png_write_info().  In PNG files, the alpha channel in an image is the
+level of opacity.  If your data is supplied as a level of
+transparency, you can invert the alpha channel before you write it, so
+that 0 is fully transparent and 255 (in 8-bit or paletted images) or
+65535 (in 16-bit images) is fully opaque, with
+
+    png_set_invert_alpha(png_ptr);
+
+This must appear before png_write_info() instead of later with the
+other transformations because in the case of paletted images the tRNS
+chunk data has to be inverted before the tRNS chunk is written.  If
+your image is not a paletted image, the tRNS data (which in such cases
+represents a single color to be rendered as transparent) won't need to
+be changed, and you can safely do this transformation after your
+png_write_info() call.
+
+If you need to write a private chunk that you want to appear before
+the PLTE chunk when PLTE is present, you can write the PNG info in
+two steps, and insert code to write your own chunk between them:
+
+    png_write_info_before_PLTE(png_ptr, info_ptr);
+    png_set_unknown_chunks(png_ptr, info_ptr, ...);
+    png_write_info(png_ptr, info_ptr);
+
+After you've written the file information, you can set up the library
+to handle any special transformations of the image data.  The various
+ways to transform the data will be described in the order that they
+should occur.  This is important, as some of these change the color
+type and/or bit depth of the data, and some others only work on
+certain color types and bit depths.  Even though each transformation
+checks to see if it has data that it can do something with, you should
+make sure to only enable a transformation if it will be valid for the
+data.  For example, don't swap red and blue on grayscale data.
+
+PNG files store RGB pixels packed into 3 or 6 bytes.  This code tells
+the library to strip input data that has 4 or 8 bytes per pixel down
+to 3 or 6 bytes (or strip 2 or 4-byte grayscale+filler data to 1 or 2
+bytes per pixel).
+
+    png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
+
+where the 0 is unused, and the location is either PNG_FILLER_BEFORE or
+PNG_FILLER_AFTER, depending upon whether the filler byte in the pixel
+is stored XRGB or RGBX.
+
+PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as
+they can, resulting in, for example, 8 pixels per byte for 1 bit files.
+If the data is supplied at 1 pixel per byte, use this code, which will
+correctly pack the pixels into a single byte:
+
+    png_set_packing(png_ptr);
+
+PNG files reduce possible bit depths to 1, 2, 4, 8, and 16.  If your
+data is of another bit depth, you can write an sBIT chunk into the
+file so that decoders can recover the original data if desired.
+
+    /* Set the true bit depth of the image data */
+    if (color_type & PNG_COLOR_MASK_COLOR)
+    {
+        sig_bit.red = true_bit_depth;
+        sig_bit.green = true_bit_depth;
+        sig_bit.blue = true_bit_depth;
+    }
+    else
+    {
+        sig_bit.gray = true_bit_depth;
+    }
+    if (color_type & PNG_COLOR_MASK_ALPHA)
+    {
+        sig_bit.alpha = true_bit_depth;
+    }
+
+    png_set_sBIT(png_ptr, info_ptr, &sig_bit);
+
+If the data is stored in the row buffer in a bit depth other than
+one supported by PNG (e.g. 3 bit data in the range 0-7 for a 4-bit PNG),
+this will scale the values to appear to be the correct bit depth as
+is required by PNG.
+
+    png_set_shift(png_ptr, &sig_bit);
+
+PNG files store 16 bit pixels in network byte order (big-endian,
+ie. most significant bits first).  This code would be used if they are
+supplied the other way (little-endian, i.e. least significant bits
+first, the way PCs store them):
+
+    if (bit_depth > 8)
+       png_set_swap(png_ptr);
+
+If you are using packed-pixel images (1, 2, or 4 bits/pixel), and you
+need to change the order the pixels are packed into bytes, you can use:
+
+    if (bit_depth < 8)
+       png_set_packswap(png_ptr);
+
+PNG files store 3 color pixels in red, green, blue order.  This code
+would be used if they are supplied as blue, green, red:
+
+    png_set_bgr(png_ptr);
+
+PNG files describe monochrome as black being zero and white being
+one. This code would be used if the pixels are supplied with this reversed
+(black being one and white being zero):
+
+    png_set_invert_mono(png_ptr);
+
+Finally, you can write your own transformation function if none of
+the existing ones meets your needs.  This is done by setting a callback
+with
+
+    png_set_write_user_transform_fn(png_ptr,
+       write_transform_fn);
+
+You must supply the function
+
+    void write_transform_fn(png_ptr ptr, row_info_ptr
+       row_info, png_bytep data)
+
+See pngtest.c for a working example.  Your function will be called
+before any of the other transformations are processed.
+
+You can also set up a pointer to a user structure for use by your
+callback function.
+
+    png_set_user_transform_info(png_ptr, user_ptr, 0, 0);
+
+The user_channels and user_depth parameters of this function are ignored
+when writing; you can set them to zero as shown.
+
+You can retrieve the pointer via the function png_get_user_transform_ptr().
+For example:
+
+    voidp write_user_transform_ptr =
+       png_get_user_transform_ptr(png_ptr);
+
+It is possible to have libpng flush any pending output, either manually,
+or automatically after a certain number of lines have been written.  To
+flush the output stream a single time call:
+
+    png_write_flush(png_ptr);
+
+and to have libpng flush the output stream periodically after a certain
+number of scanlines have been written, call:
+
+    png_set_flush(png_ptr, nrows);
+
+Note that the distance between rows is from the last time png_write_flush()
+was called, or the first row of the image if it has never been called.
+So if you write 50 lines, and then png_set_flush 25, it will flush the
+output on the next scanline, and every 25 lines thereafter, unless
+png_write_flush() is called before 25 more lines have been written.
+If nrows is too small (less than about 10 lines for a 640 pixel wide
+RGB image) the image compression may decrease noticeably (although this
+may be acceptable for real-time applications).  Infrequent flushing will
+only degrade the compression performance by a few percent over images
+that do not use flushing.
+
+.SS Writing the image data
+
+That's it for the transformations.  Now you can write the image data.
+The simplest way to do this is in one function call.  If you have the
+whole image in memory, you can just call png_write_image() and libpng
+will write the image.  You will need to pass in an array of pointers to
+each row.  This function automatically handles interlacing, so you don't
+need to call png_set_interlace_handling() or call this function multiple
+times, or any of that other stuff necessary with png_write_rows().
+
+    png_write_image(png_ptr, row_pointers);
+
+where row_pointers is:
+
+    png_byte *row_pointers[height];
+
+You can point to void or char or whatever you use for pixels.
+
+If you don't want to write the whole image at once, you can
+use png_write_rows() instead.  If the file is not interlaced,
+this is simple:
+
+    png_write_rows(png_ptr, row_pointers,
+       number_of_rows);
+
+row_pointers is the same as in the png_write_image() call.
+
+If you are just writing one row at a time, you can do this with
+a single row_pointer instead of an array of row_pointers:
+
+    png_bytep row_pointer = row;
+
+    png_write_row(png_ptr, row_pointer);
+
+When the file is interlaced, things can get a good deal more
+complicated.  The only currently (as of the PNG Specification
+version 1.2, dated July 1999) defined interlacing scheme for PNG files
+is the "Adam7" interlace scheme, that breaks down an
+image into seven smaller images of varying size.  libpng will build
+these images for you, or you can do them yourself.  If you want to
+build them yourself, see the PNG specification for details of which
+pixels to write when.
+
+If you don't want libpng to handle the interlacing details, just
+use png_set_interlace_handling() and call png_write_rows() the
+correct number of times to write all seven sub-images.
+
+If you want libpng to build the sub-images, call this before you start
+writing any rows:
+
+    number_of_passes =
+       png_set_interlace_handling(png_ptr);
+
+This will return the number of passes needed.  Currently, this
+is seven, but may change if another interlace type is added.
+
+Then write the complete image number_of_passes times.
+
+    png_write_rows(png_ptr, row_pointers,
+       number_of_rows);
+
+As some of these rows are not used, and thus return immediately,
+you may want to read about interlacing in the PNG specification,
+and only update the rows that are actually used.
+
+.SS Finishing a sequential write
+
+After you are finished writing the image, you should finish writing
+the file.  If you are interested in writing comments or time, you should
+pass an appropriately filled png_info pointer.  If you are not interested,
+you can pass NULL.
+
+    png_write_end(png_ptr, info_ptr);
+
+When you are done, you can free all memory used by libpng like this:
+
+    png_destroy_write_struct(&png_ptr, &info_ptr);
+
+It is also possible to individually free the info_ptr members that
+point to libpng-allocated storage with the following function:
+
+    png_free_data(png_ptr, info_ptr, mask, seq)
+    mask  - identifies data to be freed, a mask
+            containing the logical OR of one or
+            more of
+              PNG_FREE_PLTE, PNG_FREE_TRNS,
+              PNG_FREE_HIST, PNG_FREE_ICCP,
+              PNG_FREE_PCAL, PNG_FREE_ROWS,
+              PNG_FREE_SCAL, PNG_FREE_SPLT,
+              PNG_FREE_TEXT, PNG_FREE_UNKN,
+            or simply PNG_FREE_ALL
+    seq   - sequence number of item to be freed
+            (-1 for all items)
+
+This function may be safely called when the relevant storage has
+already been freed, or has not yet been allocated, or was allocated
+by the user  and not by libpng,  and will in those
+cases do nothing.  The "seq" parameter is ignored if only one item
+of the selected data type, such as PLTE, is allowed.  If "seq" is not
+-1, and multiple items are allowed for the data type identified in
+the mask, such as text or sPLT, only the n'th item in the structure
+is freed, where n is "seq".
+
+If you allocated data such as a palette that you passed
+in to libpng with png_set_*, you must not free it until just before the call to
+png_destroy_write_struct().
+
+The default behavior is only to free data that was allocated internally
+by libpng.  This can be changed, so that libpng will not free the data,
+or so that it will free data that was allocated by the user with png_malloc()
+or png_zalloc() and passed in via a png_set_*() function, with
+
+    png_data_freer(png_ptr, info_ptr, freer, mask)
+    mask   - which data elements are affected
+             same choices as in png_free_data()
+    freer  - one of
+               PNG_DESTROY_WILL_FREE_DATA
+               PNG_SET_WILL_FREE_DATA
+               PNG_USER_WILL_FREE_DATA
+
+For example, to transfer responsibility for some data from a read structure
+to a write structure, you could use
+
+    png_data_freer(read_ptr, read_info_ptr,
+       PNG_USER_WILL_FREE_DATA,
+       PNG_FREE_PLTE|PNG_FREE_tRNS|PNG_FREE_hIST)
+    png_data_freer(write_ptr, write_info_ptr,
+       PNG_DESTROY_WILL_FREE_DATA,
+       PNG_FREE_PLTE|PNG_FREE_tRNS|PNG_FREE_hIST)
+
+thereby briefly reassigning responsibility for freeing to the user but
+immediately afterwards reassigning it once more to the write_destroy
+function.  Having done this, it would then be safe to destroy the read
+structure and continue to use the PLTE, tRNS, and hIST data in the write
+structure.
+
+This function only affects data that has already been allocated.
+You can call this function before calling after the png_set_*() functions
+to control whether the user or png_destroy_*() is supposed to free the data.
+When the user assumes responsibility for libpng-allocated data, the
+application must use
+png_free() to free it, and when the user transfers responsibility to libpng
+for data that the user has allocated, the user must have used png_malloc()
+or png_zalloc() to allocate it.
+
+If you allocated text_ptr.text, text_ptr.lang, and text_ptr.translated_keyword
+separately, do not transfer responsibility for freeing text_ptr to libpng,
+because when libpng fills a png_text structure it combines these members with
+the key member, and png_free_data() will free only text_ptr.key.  Similarly,
+if you transfer responsibility for free'ing text_ptr from libpng to your
+application, your application must not separately free those members.
+For a more compact example of writing a PNG image, see the file example.c.
+
+.SH V. Modifying/Customizing libpng:
+
+There are three issues here.  The first is changing how libpng does
+standard things like memory allocation, input/output, and error handling.
+The second deals with more complicated things like adding new chunks,
+adding new transformations, and generally changing how libpng works.
+Both of those are compile-time issues; that is, they are generally
+determined at the time the code is written, and there is rarely a need
+to provide the user with a means of changing them.  The third is a
+run-time issue:  choosing between and/or tuning one or more alternate
+versions of computationally intensive routines; specifically, optimized
+assembly-language (and therefore compiler- and platform-dependent)
+versions.
+
+Memory allocation, input/output, and error handling
+
+All of the memory allocation, input/output, and error handling in libpng
+goes through callbacks that are user-settable.  The default routines are
+in pngmem.c, pngrio.c, pngwio.c, and pngerror.c, respectively.  To change
+these functions, call the appropriate png_set_*_fn() function.
+
+Memory allocation is done through the functions png_malloc()
+and png_free().  These currently just call the standard C functions.  If
+your pointers can't access more then 64K at a time, you will want to set
+MAXSEG_64K in zlib.h.  Since it is unlikely that the method of handling
+memory allocation on a platform will change between applications, these
+functions must be modified in the library at compile time.  If you prefer
+to use a different method of allocating and freeing data, you can use
+png_create_read_struct_2() or png_create_write_struct_2() to register
+your own functions as described above.
+These functions also provide a void pointer that can be retrieved via
+
+    mem_ptr=png_get_mem_ptr(png_ptr);
+
+Your replacement memory functions must have prototypes as follows:
+
+    png_voidp malloc_fn(png_structp png_ptr,
+       png_size_t size);
+    void free_fn(png_structp png_ptr, png_voidp ptr);
+
+Your malloc_fn() must return NULL in case of failure.  The png_malloc()
+function will normally call png_error() if it receives a NULL from the
+system memory allocator or from your replacement malloc_fn().
+
+Input/Output in libpng is done through png_read() and png_write(),
+which currently just call fread() and fwrite().  The FILE * is stored in
+png_struct and is initialized via png_init_io().  If you wish to change
+the method of I/O, the library supplies callbacks that you can set
+through the function png_set_read_fn() and png_set_write_fn() at run
+time, instead of calling the png_init_io() function.  These functions
+also provide a void pointer that can be retrieved via the function
+png_get_io_ptr().  For example:
+
+    png_set_read_fn(png_structp read_ptr,
+        voidp read_io_ptr, png_rw_ptr read_data_fn)
+
+    png_set_write_fn(png_structp write_ptr,
+        voidp write_io_ptr, png_rw_ptr write_data_fn,
+        png_flush_ptr output_flush_fn);
+
+    voidp read_io_ptr = png_get_io_ptr(read_ptr);
+    voidp write_io_ptr = png_get_io_ptr(write_ptr);
+
+The replacement I/O functions must have prototypes as follows:
+
+    void user_read_data(png_structp png_ptr,
+        png_bytep data, png_size_t length);
+    void user_write_data(png_structp png_ptr,
+        png_bytep data, png_size_t length);
+    void user_flush_data(png_structp png_ptr);
+
+Supplying NULL for the read, write, or flush functions sets them back
+to using the default C stream functions.  It is an error to read from
+a write stream, and vice versa.
+
+Error handling in libpng is done through png_error() and png_warning().
+Errors handled through png_error() are fatal, meaning that png_error()
+should never return to its caller.  Currently, this is handled via
+setjmp() and longjmp() (unless you have compiled libpng with
+PNG_SETJMP_NOT_SUPPORTED, in which case it is handled via PNG_ABORT()),
+but you could change this to do things like exit() if you should wish.
+
+On non-fatal errors, png_warning() is called
+to print a warning message, and then control returns to the calling code.
+By default png_error() and png_warning() print a message on stderr via
+fprintf() unless the library is compiled with PNG_NO_CONSOLE_IO defined
+(because you don't want the messages) or PNG_NO_STDIO defined (because
+fprintf() isn't available).  If you wish to change the behavior of the error
+functions, you will need to set up your own message callbacks.  These
+functions are normally supplied at the time that the png_struct is created.
+It is also possible to redirect errors and warnings to your own replacement
+functions after png_create_*_struct() has been called by calling:
+
+    png_set_error_fn(png_structp png_ptr,
+        png_voidp error_ptr, png_error_ptr error_fn,
+        png_error_ptr warning_fn);
+
+    png_voidp error_ptr = png_get_error_ptr(png_ptr);
+
+If NULL is supplied for either error_fn or warning_fn, then the libpng
+default function will be used, calling fprintf() and/or longjmp() if a
+problem is encountered.  The replacement error functions should have
+parameters as follows:
+
+    void user_error_fn(png_structp png_ptr,
+        png_const_charp error_msg);
+    void user_warning_fn(png_structp png_ptr,
+        png_const_charp warning_msg);
+
+The motivation behind using setjmp() and longjmp() is the C++ throw and
+catch exception handling methods.  This makes the code much easier to write,
+as there is no need to check every return code of every function call.
+However, there are some uncertainties about the status of local variables
+after a longjmp, so the user may want to be careful about doing anything after
+setjmp returns non-zero besides returning itself.  Consult your compiler
+documentation for more details.  For an alternative approach, you may wish
+to use the "cexcept" facility (see http://cexcept.sourceforge.net).
+
+.SS Custom chunks
+
+If you need to read or write custom chunks, you may need to get deeper
+into the libpng code.  The library now has mechanisms for storing
+and writing chunks of unknown type; you can even declare callbacks
+for custom chunks.  Hoewver, this may not be good enough if the
+library code itself needs to know about interactions between your
+chunk and existing `intrinsic' chunks.
+
+If you need to write a new intrinsic chunk, first read the PNG
+specification. Acquire a first level of
+understanding of how it works.  Pay particular attention to the
+sections that describe chunk names, and look at how other chunks were
+designed, so you can do things similarly.  Second, check out the
+sections of libpng that read and write chunks.  Try to find a chunk
+that is similar to yours and use it as a template.  More details can
+be found in the comments inside the code.  It is best to handle unknown
+chunks in a generic method, via callback functions, instead of by
+modifying libpng functions.
+
+If you wish to write your own transformation for the data, look through
+the part of the code that does the transformations, and check out some of
+the simpler ones to get an idea of how they work.  Try to find a similar
+transformation to the one you want to add and copy off of it.  More details
+can be found in the comments inside the code itself.
+
+.SS Configuring for 16 bit platforms
+
+You will want to look into zconf.h to tell zlib (and thus libpng) that
+it cannot allocate more then 64K at a time.  Even if you can, the memory
+won't be accessible.  So limit zlib and libpng to 64K by defining MAXSEG_64K.
+
+.SS Configuring for DOS
+
+For DOS users who only have access to the lower 640K, you will
+have to limit zlib's memory usage via a png_set_compression_mem_level()
+call.  See zlib.h or zconf.h in the zlib library for more information.
+
+.SS Configuring for Medium Model
+
+Libpng's support for medium model has been tested on most of the popular
+compilers.  Make sure MAXSEG_64K gets defined, USE_FAR_KEYWORD gets
+defined, and FAR gets defined to far in pngconf.h, and you should be
+all set.  Everything in the library (except for zlib's structure) is
+expecting far data.  You must use the typedefs with the p or pp on
+the end for pointers (or at least look at them and be careful).  Make
+note that the rows of data are defined as png_bytepp, which is an
+unsigned char far * far *.
+
+.SS Configuring for gui/windowing platforms:
+
+You will need to write new error and warning functions that use the GUI
+interface, as described previously, and set them to be the error and
+warning functions at the time that png_create_*_struct() is called,
+in order to have them available during the structure initialization.
+They can be changed later via png_set_error_fn().  On some compilers,
+you may also have to change the memory allocators (png_malloc, etc.).
+
+.SS Configuring for compiler xxx:
+
+All includes for libpng are in pngconf.h.  If you need to add/change/delete
+an include, this is the place to do it.  The includes that are not
+needed outside libpng are protected by the PNG_INTERNAL definition,
+which is only defined for those routines inside libpng itself.  The
+files in libpng proper only include png.h, which includes pngconf.h.
+
+.SS Configuring zlib:
+
+There are special functions to configure the compression.  Perhaps the
+most useful one changes the compression level, which currently uses
+input compression values in the range 0 - 9.  The library normally
+uses the default compression level (Z_DEFAULT_COMPRESSION = 6).  Tests
+have shown that for a large majority of images, compression values in
+the range 3-6 compress nearly as well as higher levels, and do so much
+faster.  For online applications it may be desirable to have maximum speed
+(Z_BEST_SPEED = 1).  With versions of zlib after v0.99, you can also
+specify no compression (Z_NO_COMPRESSION = 0), but this would create
+files larger than just storing the raw bitmap.  You can specify the
+compression level by calling:
+
+    png_set_compression_level(png_ptr, level);
+
+Another useful one is to reduce the memory level used by the library.
+The memory level defaults to 8, but it can be lowered if you are
+short on memory (running DOS, for example, where you only have 640K).
+Note that the memory level does have an effect on compression; among
+other things, lower levels will result in sections of incompressible
+data being emitted in smaller stored blocks, with a correspondingly
+larger relative overhead of up to 15% in the worst case.
+
+    png_set_compression_mem_level(png_ptr, level);
+
+The other functions are for configuring zlib.  They are not recommended
+for normal use and may result in writing an invalid PNG file.  See
+zlib.h for more information on what these mean.
+
+    png_set_compression_strategy(png_ptr,
+        strategy);
+    png_set_compression_window_bits(png_ptr,
+        window_bits);
+    png_set_compression_method(png_ptr, method);
+    png_set_compression_buffer_size(png_ptr, size);
+
+.SS Controlling row filtering
+
+If you want to control whether libpng uses filtering or not, which
+filters are used, and how it goes about picking row filters, you
+can call one of these functions.  The selection and configuration
+of row filters can have a significant impact on the size and
+encoding speed and a somewhat lesser impact on the decoding speed
+of an image.  Filtering is enabled by default for RGB and grayscale
+images (with and without alpha), but not for paletted images nor
+for any images with bit depths less than 8 bits/pixel.
+
+The 'method' parameter sets the main filtering method, which is
+currently only '0' in the PNG 1.2 specification.  The 'filters'
+parameter sets which filter(s), if any, should be used for each
+scanline.  Possible values are PNG_ALL_FILTERS and PNG_NO_FILTERS
+to turn filtering on and off, respectively.
+
+Individual filter types are PNG_FILTER_NONE, PNG_FILTER_SUB,
+PNG_FILTER_UP, PNG_FILTER_AVG, PNG_FILTER_PAETH, which can be bitwise
+ORed together with '|' to specify one or more filters to use.
+These filters are described in more detail in the PNG specification.
+If you intend to change the filter type during the course of writing
+the image, you should start with flags set for all of the filters
+you intend to use so that libpng can initialize its internal
+structures appropriately for all of the filter types.  (Note that this
+means the first row must always be adaptively filtered, because libpng
+currently does not allocate the filter buffers until png_write_row()
+is called for the first time.)
+
+    filters = PNG_FILTER_NONE | PNG_FILTER_SUB
+              PNG_FILTER_UP | PNG_FILTER_AVE |
+              PNG_FILTER_PAETH | PNG_ALL_FILTERS;
+
+    png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE,
+       filters);
+              The second parameter can also be
+              PNG_INTRAPIXEL_DIFFERENCING if you are
+              writing a PNG to be embedded in a MNG
+              datastream.  This parameter must be the
+              same as the value of filter_method used
+              in png_set_IHDR().
+
+It is also possible to influence how libpng chooses from among the
+available filters.  This is done in one or both of two ways - by
+telling it how important it is to keep the same filter for successive
+rows, and by telling it the relative computational costs of the filters.
+
+    double weights[3] = {1.5, 1.3, 1.1},
+       costs[PNG_FILTER_VALUE_LAST] =
+       {1.0, 1.3, 1.3, 1.5, 1.7};
+
+    png_set_filter_heuristics(png_ptr,
+       PNG_FILTER_HEURISTIC_WEIGHTED, 3,
+       weights, costs);
+
+The weights are multiplying factors that indicate to libpng that the
+row filter should be the same for successive rows unless another row filter
+is that many times better than the previous filter.  In the above example,
+if the previous 3 filters were SUB, SUB, NONE, the SUB filter could have a
+"sum of absolute differences" 1.5 x 1.3 times higher than other filters
+and still be chosen, while the NONE filter could have a sum 1.1 times
+higher than other filters and still be chosen.  Unspecified weights are
+taken to be 1.0, and the specified weights should probably be declining
+like those above in order to emphasize recent filters over older filters.
+
+The filter costs specify for each filter type a relative decoding cost
+to be considered when selecting row filters.  This means that filters
+with higher costs are less likely to be chosen over filters with lower
+costs, unless their "sum of absolute differences" is that much smaller.
+The costs do not necessarily reflect the exact computational speeds of
+the various filters, since this would unduly influence the final image
+size.
+
+Note that the numbers above were invented purely for this example and
+are given only to help explain the function usage.  Little testing has
+been done to find optimum values for either the costs or the weights.
+
+.SS Removing unwanted object code
+
+There are a bunch of #define's in pngconf.h that control what parts of
+libpng are compiled.  All the defines end in _SUPPORTED.  If you are
+never going to use a capability, you can change the #define to #undef
+before recompiling libpng and save yourself code and data space, or
+you can turn off individual capabilities with defines that begin with
+PNG_NO_.
+
+You can also turn all of the transforms and ancillary chunk capabilities
+off en masse with compiler directives that define
+PNG_NO_READ[or WRITE]_TRANSFORMS, or PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS,
+or all four,
+along with directives to turn on any of the capabilities that you do
+want.  The PNG_NO_READ[or WRITE]_TRANSFORMS directives disable
+the extra transformations but still leave the library fully capable of reading
+and writing PNG files with all known public chunks
+Use of the PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS directive
+produces a library that is incapable of reading or writing ancillary chunks.
+If you are not using the progressive reading capability, you can
+turn that off with PNG_NO_PROGRESSIVE_READ (don't confuse
+this with the INTERLACING capability, which you'll still have).
+
+All the reading and writing specific code are in separate files, so the
+linker should only grab the files it needs.  However, if you want to
+make sure, or if you are building a stand alone library, all the
+reading files start with pngr and all the writing files start with
+pngw.  The files that don't match either (like png.c, pngtrans.c, etc.)
+are used for both reading and writing, and always need to be included.
+The progressive reader is in pngpread.c
+
+If you are creating or distributing a dynamically linked library (a .so
+or DLL file), you should not remove or disable any parts of the library,
+as this will cause applications linked with different versions of the
+library to fail if they call functions not available in your library.
+The size of the library itself should not be an issue, because only
+those sections that are actually used will be loaded into memory.
+
+.SS Requesting debug printout
+
+The macro definition PNG_DEBUG can be used to request debugging
+printout.  Set it to an integer value in the range 0 to 3.  Higher
+numbers result in increasing amounts of debugging information.  The
+information is printed to the "stderr" file, unless another file
+name is specified in the PNG_DEBUG_FILE macro definition.
+
+When PNG_DEBUG > 0, the following functions (macros) become available:
+
+   png_debug(level, message)
+   png_debug1(level, message, p1)
+   png_debug2(level, message, p1, p2)
+
+in which "level" is compared to PNG_DEBUG to decide whether to print
+the message, "message" is the formatted string to be printed,
+and p1 and p2 are parameters that are to be embedded in the string
+according to printf-style formatting directives.  For example,
+
+   png_debug1(2, "foo=%d\n", foo);
+
+is expanded to
+
+   if(PNG_DEBUG > 2)
+     fprintf(PNG_DEBUG_FILE, "foo=%d\n", foo);
+
+When PNG_DEBUG is defined but is zero, the macros aren't defined, but you
+can still use PNG_DEBUG to control your own debugging:
+
+   #ifdef PNG_DEBUG
+       fprintf(stderr, ...
+   #endif
+
+When PNG_DEBUG = 1, the macros are defined, but only png_debug statements
+having level = 0 will be printed.  There aren't any such statements in
+this version of libpng, but if you insert some they will be printed.
+
+.SH VI.  Runtime optimization
+
+A new feature in libpng 1.2.0 is the ability to dynamically switch between
+standard and optimized versions of some routines.  Currently these are
+limited to three computationally intensive tasks when reading PNG files:
+decoding row filters, expanding interlacing, and combining interlaced or
+transparent row data with previous row data.  Currently the optimized
+versions are available only for x86 (Intel, AMD, etc.) platforms with
+MMX support, though this may change in future versions.  (For example,
+the non-MMX assembler optimizations for zlib might become similarly
+runtime-selectable in future releases, in which case libpng could be
+extended to support them.  Alternatively, the compile-time choice of
+floating-point versus integer routines for gamma correction might become
+runtime-selectable.)
+
+Because such optimizations tend to be very platform- and compiler-dependent,
+both in how they are written and in how they perform, the new runtime code
+in libpng has been written to allow programs to query, enable, and disable
+either specific optimizations or all such optimizations.  For example, to
+enable all possible optimizations (bearing in mind that some "optimizations"
+may actually run more slowly in rare cases):
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       png_uint_32 mask, flags;
+
+       flags = png_get_asm_flags(png_ptr);
+       mask = png_get_asm_flagmask(PNG_SELECT_READ | PNG_SELECT_WRITE);
+       png_set_asm_flags(png_ptr, flags | mask);
+    #endif
+
+To enable only optimizations relevant to reading PNGs, use PNG_SELECT_READ
+by itself when calling png_get_asm_flagmask(); similarly for optimizing
+only writing.  To disable all optimizations:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       flags = png_get_asm_flags(png_ptr);
+       mask = png_get_asm_flagmask(PNG_SELECT_READ | PNG_SELECT_WRITE);
+       png_set_asm_flags(png_ptr, flags & ~mask);
+    #endif
+
+To enable or disable only MMX-related features, use png_get_mmx_flagmask()
+in place of png_get_asm_flagmask().  The mmx version takes one additional
+parameter:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       int selection = PNG_SELECT_READ | PNG_SELECT_WRITE;
+       int compilerID;
+
+       mask = png_get_mmx_flagmask(selection, &compilerID);
+    #endif
+
+On return, compilerID will indicate which version of the MMX assembler
+optimizations was compiled.  Currently two flavors exist:  Microsoft
+Visual C++ (compilerID == 1) and GNU C (a.k.a. gcc/gas, compilerID == 2).
+On non-x86 platforms or on systems compiled without MMX optimizations, a
+value of -1 is used.
+
+Note that both png_get_asm_flagmask() and png_get_mmx_flagmask() return
+all valid, settable optimization bits for the version of the library that's
+currently in use.  In the case of shared (dynamically linked) libraries,
+this may include optimizations that did not exist at the time the code was
+written and compiled.  It is also possible, of course, to enable only known,
+specific optimizations; for example:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       flags = PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
+             | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ;
+       png_set_asm_flags(png_ptr, flags);
+    #endif
+
+This method would enable only the MMX read-optimizations available at the
+time of libpng 1.2.0's release, regardless of whether a later version of
+the DLL were actually being used.  (Also note that these functions did not
+exist in versions older than 1.2.0, so any attempt to run a dynamically
+linked app on such an older version would fail.)
+
+To determine whether the processor supports MMX instructions at all, use
+the png_mmx_support() function:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       mmxsupport = png_mmx_support();
+    #endif
+
+It returns -1 if MMX support is not compiled into libpng, 0 if MMX code
+is compiled but MMX is not supported by the processor, or 1 if MMX support
+is fully available.  Note that png_mmx_support(), png_get_mmx_flagmask(),
+and png_get_asm_flagmask() all may be called without allocating and ini-
+tializing any PNG structures (for example, as part of a usage screen or
+"about" box).
+
+The following code can be used to prevent an application from using the
+thread_unsafe features, even if libpng was built with PNG_THREAD_UNSAFE_OK
+defined:
+
+#if defined(PNG_USE_PNGGCCRD) && defined(PNG_ASSEMBLER_CODE_SUPPORTED) \
+  && defined(PNG_THREAD_UNSAFE_OK)
+    /* Disable thread-unsafe features of pnggccrd */
+    if (png_access_version() >= 10200)
+    {
+      png_uint_32 mmx_disable_mask = 0;
+      png_uint_32 asm_flags;
+
+      mmx_disable_mask |= ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
+                          | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
+                          | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
+                          | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH );
+      asm_flags = png_get_asm_flags(png_ptr);
+      png_set_asm_flags(png_ptr, asm_flags & ~mmx_disable_mask);
+    }
+#endif
+
+For more extensive examples of runtime querying, enabling and disabling
+of optimized features, see contrib/gregbook/readpng2.c in the libpng
+source-code distribution.
+
+.SH VII.  MNG support
+
+The MNG specification (available at http://www.libpng.org/pub/mng) allows
+certain extensions to PNG for PNG images that are embedded in MNG datastreams.
+Libpng can support some of these extensions.  To enable them, use the
+png_permit_mng_features() function:
+
+   feature_set = png_permit_mng_features(png_ptr, mask)
+   mask is a png_uint_32 containing the logical OR of the
+        features you want to enable.  These include
+        PNG_FLAG_MNG_EMPTY_PLTE
+        PNG_FLAG_MNG_FILTER_64
+        PNG_ALL_MNG_FEATURES
+   feature_set is a png_uint_32 that is the logical AND of
+      your mask with the set of MNG features that is
+      supported by the version of libpng that you are using.
+
+It is an error to use this function when reading or writing a standalone
+PNG file with the PNG 8-byte signature.  The PNG datastream must be wrapped
+in a MNG datastream.  As a minimum, it must have the MNG 8-byte signature
+and the MHDR and MEND chunks.  Libpng does not provide support for these
+or any other MNG chunks; your application must provide its own support for
+them.  You may wish to consider using libmng (available at
+http://www.libmng.com) instead.
+
+.SH VIII.  Changes to Libpng from version 0.88
+
+It should be noted that versions of libpng later than 0.96 are not
+distributed by the original libpng author, Guy Schalnat, nor by
+Andreas Dilger, who had taken over from Guy during 1996 and 1997, and
+distributed versions 0.89 through 0.96, but rather by another member
+of the original PNG Group, Glenn Randers-Pehrson.  Guy and Andreas are
+still alive and well, but they have moved on to other things.
+
+The old libpng functions png_read_init(), png_write_init(),
+png_info_init(), png_read_destroy(), and png_write_destroy() have been
+moved to PNG_INTERNAL in version 0.95 to discourage their use.  These
+functions will be removed from libpng version 2.0.0.
+
+The preferred method of creating and initializing the libpng structures is
+via the png_create_read_struct(), png_create_write_struct(), and
+png_create_info_struct() because they isolate the size of the structures
+from the application, allow version error checking, and also allow the
+use of custom error handling routines during the initialization, which
+the old functions do not.  The functions png_read_destroy() and
+png_write_destroy() do not actually free the memory that libpng
+allocated for these structs, but just reset the data structures, so they
+can be used instead of png_destroy_read_struct() and
+png_destroy_write_struct() if you feel there is too much system overhead
+allocating and freeing the png_struct for each image read.
+
+Setting the error callbacks via png_set_message_fn() before
+png_read_init() as was suggested in libpng-0.88 is no longer supported
+because this caused applications that do not use custom error functions
+to fail if the png_ptr was not initialized to zero.  It is still possible
+to set the error callbacks AFTER png_read_init(), or to change them with
+png_set_error_fn(), which is essentially the same function, but with a new
+name to force compilation errors with applications that try to use the old
+method.
+
+Starting with version 1.0.7, you can find out which version of the library
+you are using at run-time:
+
+   png_uint_32 libpng_vn = png_access_version_number();
+
+The number libpng_vn is constructed from the major version, minor
+version with leading zero, and release number with leading zero,
+(e.g., libpng_vn for version 1.0.7 is 10007).
+
+You can also check which version of png.h you used when compiling your
+application:
+
+   png_uint_32 application_vn = PNG_LIBPNG_VER;
+
+.SH IX. Y2K Compliance in libpng
+
+December 3, 2004
+
+Since the PNG Development group is an ad-hoc body, we can't make
+an official declaration.
+
+This is your unofficial assurance that libpng from version 0.71 and
+upward through 1.2.8 are Y2K compliant.  It is my belief that earlier
+versions were also Y2K compliant.
+
+Libpng only has three year fields.  One is a 2-byte unsigned integer that
+will hold years up to 65535.  The other two hold the date in text
+format, and will hold years up to 9999.
+
+The integer is
+    "png_uint_16 year" in png_time_struct.
+
+The strings are
+    "png_charp time_buffer" in png_struct and
+    "near_time_buffer", which is a local character string in png.c.
+
+There are seven time-related functions:
+
+    png_convert_to_rfc_1123() in png.c
+      (formerly png_convert_to_rfc_1152() in error)
+    png_convert_from_struct_tm() in pngwrite.c, called
+      in pngwrite.c
+    png_convert_from_time_t() in pngwrite.c
+    png_get_tIME() in pngget.c
+    png_handle_tIME() in pngrutil.c, called in pngread.c
+    png_set_tIME() in pngset.c
+    png_write_tIME() in pngwutil.c, called in pngwrite.c
+
+All appear to handle dates properly in a Y2K environment.  The
+png_convert_from_time_t() function calls gmtime() to convert from system
+clock time, which returns (year - 1900), which we properly convert to
+the full 4-digit year.  There is a possibility that applications using
+libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
+function, or that they are incorrectly passing only a 2-digit year
+instead of "year - 1900" into the png_convert_from_struct_tm() function,
+but this is not under our control.  The libpng documentation has always
+stated that it works with 4-digit years, and the APIs have been
+documented as such.
+
+The tIME chunk itself is also Y2K compliant.  It uses a 2-byte unsigned
+integer to hold the year, and can hold years as large as 65535.
+
+zlib, upon which libpng depends, is also Y2K compliant.  It contains
+no date-related code.
+
+
+   Glenn Randers-Pehrson
+   libpng maintainer
+   PNG Development Group
+
+.SH NOTE
+
+Note about libpng version numbers:
+
+Due to various miscommunications, unforeseen code incompatibilities
+and occasional factors outside the authors' control, version numbering
+on the library has not always been consistent and straightforward.
+The following table summarizes matters since version 0.89c, which was
+the first widely used release:
+
+ source             png.h  png.h  shared-lib
+ version            string   int  version
+ -------            ------  ----- ----------
+ 0.89c ("beta 3")  0.89       89  1.0.89
+ 0.90  ("beta 4")  0.90       90  0.90
+ 0.95  ("beta 5")  0.95       95  0.95
+ 0.96  ("beta 6")  0.96       96  0.96
+ 0.97b ("beta 7")  1.00.97    97  1.0.1
+ 0.97c             0.97       97  2.0.97
+ 0.98              0.98       98  2.0.98
+ 0.99              0.99       98  2.0.99
+ 0.99a-m           0.99       99  2.0.99
+ 1.00              1.00      100  2.1.0
+ 1.0.0             1.0.0     100  2.1.0
+ 1.0.0   (from here on, the  100  2.1.0
+ 1.0.1    png.h string is  10001  2.1.0
+ 1.0.1a-e identical to the 10002  from here on, the
+ 1.0.2    source version)  10002  shared library is 2.V
+ 1.0.2a-b                  10003  where V is the source
+ 1.0.1                     10001  code version except as
+ 1.0.1a-e                  10002  2.1.0.1a-e   noted.
+ 1.0.2                     10002  2.1.0.2
+ 1.0.2a-b                  10003  2.1.0.2a-b
+ 1.0.3                     10003  2.1.0.3
+ 1.0.3a-d                  10004  2.1.0.3a-d
+ 1.0.4                     10004  2.1.0.4
+ 1.0.4a-f                  10005  2.1.0.4a-f
+ 1.0.5 (+ 2 patches)       10005  2.1.0.5
+ 1.0.5a-d                  10006  2.1.0.5a-d
+ 1.0.5e-r                  10100  2.1.0.5e-r
+ 1.0.5s-v                  10006  2.1.0.5s-v
+ 1.0.6 (+ 3 patches)       10006  2.1.0.6
+ 1.0.6d-g                  10007  2.1.0.6d-g
+ 1.0.6h                    10007  10.6h
+ 1.0.6i                    10007  10.6i
+ 1.0.6j                    10007  2.1.0.6j
+ 1.0.7beta11-14    DLLNUM  10007  2.1.0.7beta11-14
+ 1.0.7beta15-18       1    10007  2.1.0.7beta15-18
+ 1.0.7rc1-2           1    10007  2.1.0.7rc1-2
+ 1.0.7                1    10007  2.1.0.7
+ 1.0.8beta1-4         1    10008  2.1.0.8beta1-4
+ 1.0.8rc1             1    10008  2.1.0.8rc1
+ 1.0.8                1    10008  2.1.0.8
+ 1.0.9beta1-6         1    10009  2.1.0.9beta1-6
+ 1.0.9rc1             1    10009  2.1.0.9rc1
+ 1.0.9beta7-10        1    10009  2.1.0.9beta7-10
+ 1.0.9rc2             1    10009  2.1.0.9rc2
+ 1.0.9                1    10009  2.1.0.9
+ 1.0.10beta1          1    10010  2.1.0.10beta1
+ 1.0.10rc1            1    10010  2.1.0.10rc1
+ 1.0.10               1    10010  2.1.0.10
+ 1.0.11beta1-3        1    10011  2.1.0.11beta1-3
+ 1.0.11rc1            1    10011  2.1.0.11rc1
+ 1.0.11               1    10011  2.1.0.11
+ 1.0.12beta1-2        2    10012  2.1.0.12beta1-2
+ 1.0.12rc1            2    10012  2.1.0.12rc1
+ 1.0.12               2    10012  2.1.0.12
+ 1.1.0a-f             -    10100  2.1.1.0a-f abandoned
+ 1.2.0beta1-2         2    10200  2.1.2.0beta1-2
+ 1.2.0beta3-5         3    10200  3.1.2.0beta3-5
+ 1.2.0rc1             3    10200  3.1.2.0rc1
+ 1.2.0                3    10200  3.1.2.0
+ 1.2.1beta-4          3    10201  3.1.2.1beta1-4
+ 1.2.1rc1-2           3    10201  3.1.2.1rc1-2
+ 1.2.1                3    10201  3.1.2.1
+ 1.2.2beta1-6        12    10202  12.so.0.1.2.2beta1-6
+ 1.0.13beta1         10    10013  10.so.0.1.0.13beta1
+ 1.0.13rc1           10    10013  10.so.0.1.0.13rc1
+ 1.2.2rc1            12    10202  12.so.0.1.2.2rc1
+ 1.0.13              10    10013  10.so.0.1.0.13
+ 1.2.2               12    10202  12.so.0.1.2.2
+ 1.2.3rc1-6          12    10203  12.so.0.1.2.3rc1-6
+ 1.2.3               12    10203  12.so.0.1.2.3
+ 1.2.4beta1-3        13    10204  12.so.0.1.2.4beta1-3
+ 1.2.4rc1            13    10204  12.so.0.1.2.4rc1
+ 1.0.14              10    10014  10.so.0.1.0.14
+ 1.2.4               13    10204  12.so.0.1.2.4
+ 1.2.5beta1-2        13    10205  12.so.0.1.2.5beta1-2
+ 1.0.15rc1           10    10015  10.so.0.1.0.15rc1
+ 1.0.15              10    10015  10.so.0.1.0.15
+ 1.2.5               13    10205  12.so.0.1.2.5
+ 1.2.6beta1-4        13    10206  12.so.0.1.2.6beta1-4
+ 1.2.6rc1-5          13    10206  12.so.0.1.2.6rc1-5
+ 1.0.16              10    10016  10.so.0.1.0.16
+ 1.2.6               13    10206  12.so.0.1.2.6
+ 1.2.7beta1-2        13    10207  12.so.0.1.2.7beta1-2
+ 1.0.17rc1           10    10017  12.so.0.1.0.17rc1
+ 1.2.7rc1            13    10207  12.so.0.1.2.7rc1
+ 1.0.17              10    10017  12.so.0.1.0.17
+ 1.2.7               13    10207  12.so.0.1.2.7
+ 1.2.8beta1-5        13    10208  12.so.0.1.2.8beta1-5
+ 1.0.18rc1-5         10    10018  12.so.0.1.0.18rc1-5
+ 1.2.8rc1-5          13    10208  12.so.0.1.2.8rc1-5
+ 1.0.18              10    10018  12.so.0.1.0.18
+ 1.2.8               13    10208  12.so.0.1.2.8
+
+Henceforth the source version will match the shared-library minor
+and patch numbers; the shared-library major version number will be
+used for changes in backward compatibility, as it is intended.  The
+PNG_PNGLIB_VER macro, which is not used within libpng but is available
+for applications, is an unsigned integer of the form xyyzz corresponding
+to the source version x.y.z (leading zeros in y and z).  Beta versions
+were given the previous public release number plus a letter, until
+version 1.0.6j; from then on they were given the upcoming public
+release number plus "betaNN" or "rcN".
+
+.SH "SEE ALSO"
+libpngpf(3), png(5)
+.LP
+.IR libpng :
+.IP
+http://libpng.sourceforge.net (follow the [DOWNLOAD] link)
+http://www.libpng.org/pub/png
+
+.LP
+.IR zlib :
+.IP
+(generally) at the same location as
+.I libpng
+or at
+.br
+ftp://ftp.info-zip.org/pub/infozip/zlib
+
+.LP
+.IR PNG specification: RFC 2083
+.IP
+(generally) at the same location as
+.I libpng
+or at
+.br
+ftp://ds.internic.net/rfc/rfc2083.txt
+.br
+or (as a W3C Recommendation) at
+.br
+http://www.w3.org/TR/REC-png.html
+
+.LP
+In the case of any inconsistency between the PNG specification
+and this library, the specification takes precedence.
+
+.SH AUTHORS
+This man page: Glenn Randers-Pehrson
+<glennrp at users.sourceforge.net>
+
+The contributing authors would like to thank all those who helped
+with testing, bug fixes, and patience.  This wouldn't have been
+possible without all of you.
+
+Thanks to Frank J. T. Wojcik for helping with the documentation.
+
+Libpng version 1.2.8 - December 3, 2004:
+Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
+Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
+
+Supported by the PNG development group
+.br
+png-implement at ccrc.wustl.edu (subscription required; write to
+majordomo at ccrc.wustl.edu with "subscribe png-implement" in the message).
+
+.SH COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
+
+(This copy of the libpng notices is provided for your convenience.  In case of
+any discrepancy between this copy and the notices in the file png.h that is
+included in the libpng distribution, the latter shall prevail.)
+
+If you modify libpng you may insert additional notices immediately following
+this sentence.
+
+libpng version 1.2.6, December 3, 2004, is
+Copyright (c) 2004 Glenn Randers-Pehrson, and is
+distributed according to the same disclaimer and license as libpng-1.2.5
+with the following individual added to the list of Contributing Authors
+
+   Cosmin Truta
+
+libpng versions 1.0.7, July 1, 2000, through 1.2.5 - October 3, 2002, are
+Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
+distributed according to the same disclaimer and license as libpng-1.0.6
+with the following individuals added to the list of Contributing Authors
+
+   Simon-Pierre Cadieux
+   Eric S. Raymond
+   Gilles Vollant
+
+and with the following additions to the disclaimer:
+
+   There is no warranty against interference with your
+   enjoyment of the library or against infringement.
+   There is no warranty that our efforts or the library
+   will fulfill any of your particular purposes or needs.
+   This library is provided with all faults, and the entire
+   risk of satisfactory quality, performance, accuracy, and
+   effort is with the user.
+
+libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
+Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+Distributed according to the same disclaimer and license as libpng-0.96,
+with the following individuals added to the list of Contributing Authors:
+
+   Tom Lane
+   Glenn Randers-Pehrson
+   Willem van Schaik
+
+libpng versions 0.89, June 1996, through 0.96, May 1997, are
+Copyright (c) 1996, 1997 Andreas Dilger
+Distributed according to the same disclaimer and license as libpng-0.88,
+with the following individuals added to the list of Contributing Authors:
+
+   John Bowler
+   Kevin Bracey
+   Sam Bushell
+   Magnus Holmgren
+   Greg Roelofs
+   Tom Tanner
+
+libpng versions 0.5, May 1995, through 0.88, January 1996, are
+Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+
+For the purposes of this copyright and license, "Contributing Authors"
+is defined as the following set of individuals:
+
+   Andreas Dilger
+   Dave Martindale
+   Guy Eric Schalnat
+   Paul Schmidt
+   Tim Wegner
+
+The PNG Reference Library is supplied "AS IS".  The Contributing Authors
+and Group 42, Inc. disclaim all warranties, expressed or implied,
+including, without limitation, the warranties of merchantability and of
+fitness for any purpose.  The Contributing Authors and Group 42, Inc.
+assume no liability for direct, indirect, incidental, special, exemplary,
+or consequential damages, which may result from the use of the PNG
+Reference Library, even if advised of the possibility of such damage.
+
+Permission is hereby granted to use, copy, modify, and distribute this
+source code, or portions hereof, for any purpose, without fee, subject
+to the following restrictions:
+
+1. The origin of this source code must not be misrepresented.
+
+2. Altered versions must be plainly marked as such and
+   must not be misrepresented as being the original source.
+
+3. This Copyright notice may not be removed or altered from
+   any source or altered source distribution.
+
+The Contributing Authors and Group 42, Inc. specifically permit, without
+fee, and encourage the use of this source code as a component to
+supporting the PNG file format in commercial products.  If you use this
+source code in a product, acknowledgment is not required but would be
+appreciated.
+
+
+A "png_get_copyright" function is available, for convenient use in "about"
+boxes and the like:
+
+   printf("%s",png_get_copyright(NULL));
+
+Also, the PNG logo (in PNG format, of course) is supplied in the
+files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
+
+Libpng is OSI Certified Open Source Software.  OSI Certified Open Source is a
+certification mark of the Open Source Initiative.
+
+Glenn Randers-Pehrson
+glennrp at users.sourceforge.net
+December 3, 2004
+
+.\" end of man page
+
diff --git a/gs/libpng/libpng.txt b/gs/libpng/libpng.txt
new file mode 100644
index 000000000..9360f33b3
--- /dev/null
+++ b/gs/libpng/libpng.txt
@@ -0,0 +1,2959 @@
+libpng.txt - A description on how to use and modify libpng
+
+ libpng version 1.2.8 - December 3, 2004
+ Updated and distributed by Glenn Randers-Pehrson
+ <glennrp at users.sourceforge.net>
+ Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ For conditions of distribution and use, see copyright
+ notice in png.h.
+
+ based on:
+
+ libpng 1.0 beta 6  version 0.96 May 28, 1997
+ Updated and distributed by Andreas Dilger
+ Copyright (c) 1996, 1997 Andreas Dilger
+
+ libpng 1.0 beta 2 - version 0.88  January 26, 1996
+ For conditions of distribution and use, see copyright
+ notice in png.h. Copyright (c) 1995, 1996 Guy Eric
+ Schalnat, Group 42, Inc.
+
+ Updated/rewritten per request in the libpng FAQ
+ Copyright (c) 1995, 1996 Frank J. T. Wojcik
+ December 18, 1995 & January 20, 1996
+
+I. Introduction
+
+This file describes how to use and modify the PNG reference library
+(known as libpng) for your own use.  There are five sections to this
+file: introduction, structures, reading, writing, and modification and
+configuration notes for various special platforms.  In addition to this
+file, example.c is a good starting point for using the library, as
+it is heavily commented and should include everything most people
+will need.  We assume that libpng is already installed; see the
+INSTALL file for instructions on how to install libpng.
+
+Libpng was written as a companion to the PNG specification, as a way
+of reducing the amount of time and effort it takes to support the PNG
+file format in application programs.
+
+The PNG specification (second edition), November 2003, is available as
+a W3C Recommendation and as an ISO Standard (ISO/IEC 15948:2003 (E)) at
+<http://www.w3.org/TR/2003/REC-PNG-20031110/
+The W3C and ISO documents have identical technical content.
+
+The PNG-1.2 specification is available at
+<http://www.libpng.org/pub/png/documents/>
+
+The PNG-1.0 specification is available
+as RFC 2083 <http://www.libpng.org/pub/png/documents/> and as a
+W3C Recommendation <http://www.w3.org/TR/REC.png.html>. Some
+additional chunks are described in the special-purpose public chunks
+documents at <http://www.libpng.org/pub/png/documents/>.
+
+Other information
+about PNG, and the latest version of libpng, can be found at the PNG home
+page, <http://www.libpng.org/pub/png/>.
+
+Most users will not have to modify the library significantly; advanced
+users may want to modify it more.  All attempts were made to make it as
+complete as possible, while keeping the code easy to understand.
+Currently, this library only supports C.  Support for other languages
+is being considered.
+
+Libpng has been designed to handle multiple sessions at one time,
+to be easily modifiable, to be portable to the vast majority of
+machines (ANSI, K&R, 16-, 32-, and 64-bit) available, and to be easy
+to use.  The ultimate goal of libpng is to promote the acceptance of
+the PNG file format in whatever way possible.  While there is still
+work to be done (see the TODO file), libpng should cover the
+majority of the needs of its users.
+
+Libpng uses zlib for its compression and decompression of PNG files.
+Further information about zlib, and the latest version of zlib, can
+be found at the zlib home page, <http://www.info-zip.org/pub/infozip/zlib/>.
+The zlib compression utility is a general purpose utility that is
+useful for more than PNG files, and can be used without libpng.
+See the documentation delivered with zlib for more details.
+You can usually find the source files for the zlib utility wherever you
+find the libpng source files.
+
+Libpng is thread safe, provided the threads are using different
+instances of the structures.  Each thread should have its own
+png_struct and png_info instances, and thus its own image.
+Libpng does not protect itself against two threads using the
+same instance of a structure.  Note: thread safety may be defeated
+by use of some of the MMX assembler code in pnggccrd.c, which is only
+compiled when the user defines PNG_THREAD_UNSAFE_OK.
+
+II. Structures
+
+There are two main structures that are important to libpng, png_struct
+and png_info.  The first, png_struct, is an internal structure that
+will not, for the most part, be used by a user except as the first
+variable passed to every libpng function call.
+
+The png_info structure is designed to provide information about the
+PNG file.  At one time, the fields of png_info were intended to be
+directly accessible to the user.  However, this tended to cause problems
+with applications using dynamically loaded libraries, and as a result
+a set of interface functions for png_info (the png_get_*() and png_set_*()
+functions) was developed.  The fields of png_info are still available for
+older applications, but it is suggested that applications use the new
+interfaces if at all possible.
+
+Applications that do make direct access to the members of png_struct (except
+for png_ptr->jmpbuf) must be recompiled whenever the library is updated,
+and applications that make direct access to the members of png_info must
+be recompiled if they were compiled or loaded with libpng version 1.0.6,
+in which the members were in a different order.  In version 1.0.7, the
+members of the png_info structure reverted to the old order, as they were
+in versions 0.97c through 1.0.5.  Starting with version 2.0.0, both
+structures are going to be hidden, and the contents of the structures will
+only be accessible through the png_get/png_set functions.
+
+The png.h header file is an invaluable reference for programming with libpng.
+And while I'm on the topic, make sure you include the libpng header file:
+
+#include <png.h>
+
+III. Reading
+
+We'll now walk you through the possible functions to call when reading
+in a PNG file sequentially, briefly explaining the syntax and purpose
+of each one.  See example.c and png.h for more detail.  While
+progressive reading is covered in the next section, you will still
+need some of the functions discussed in this section to read a PNG
+file.
+
+Setup
+
+You will want to do the I/O initialization(*) before you get into libpng,
+so if it doesn't work, you don't have much to undo.  Of course, you
+will also want to insure that you are, in fact, dealing with a PNG
+file.  Libpng provides a simple check to see if a file is a PNG file.
+To use it, pass in the first 1 to 8 bytes of the file to the function
+png_sig_cmp(), and it will return 0 if the bytes match the corresponding
+bytes of the PNG signature, or nonzero otherwise.  Of course, the more bytes
+you pass in, the greater the accuracy of the prediction.
+
+If you are intending to keep the file pointer open for use in libpng,
+you must ensure you don't read more than 8 bytes from the beginning
+of the file, and you also have to make a call to png_set_sig_bytes_read()
+with the number of bytes you read from the beginning.  Libpng will
+then only check the bytes (if any) that your program didn't read.
+
+(*): If you are not using the standard I/O functions, you will need
+to replace them with custom functions.  See the discussion under
+Customizing libpng.
+
+
+    FILE *fp = fopen(file_name, "rb");
+    if (!fp)
+    {
+        return (ERROR);
+    }
+    fread(header, 1, number, fp);
+    is_png = !png_sig_cmp(header, 0, number);
+    if (!is_png)
+    {
+        return (NOT_PNG);
+    }
+
+
+Next, png_struct and png_info need to be allocated and initialized.  In
+order to ensure that the size of these structures is correct even with a
+dynamically linked libpng, there are functions to initialize and
+allocate the structures.  We also pass the library version, optional
+pointers to error handling functions, and a pointer to a data struct for
+use by the error functions, if necessary (the pointer and functions can
+be NULL if the default error handlers are to be used).  See the section
+on Changes to Libpng below regarding the old initialization functions.
+The structure allocation functions quietly return NULL if they fail to
+create the structure, so your application should check for that.
+
+    png_structp png_ptr = png_create_read_struct
+       (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+        user_error_fn, user_warning_fn);
+    if (!png_ptr)
+        return (ERROR);
+
+    png_infop info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr)
+    {
+        png_destroy_read_struct(&png_ptr,
+           (png_infopp)NULL, (png_infopp)NULL);
+        return (ERROR);
+    }
+
+    png_infop end_info = png_create_info_struct(png_ptr);
+    if (!end_info)
+    {
+        png_destroy_read_struct(&png_ptr, &info_ptr,
+          (png_infopp)NULL);
+        return (ERROR);
+    }
+
+If you want to use your own memory allocation routines,
+define PNG_USER_MEM_SUPPORTED and use
+png_create_read_struct_2() instead of png_create_read_struct():
+
+    png_structp png_ptr = png_create_read_struct_2
+       (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+        user_error_fn, user_warning_fn, (png_voidp)
+        user_mem_ptr, user_malloc_fn, user_free_fn);
+
+The error handling routines passed to png_create_read_struct()
+and the memory alloc/free routines passed to png_create_struct_2()
+are only necessary if you are not using the libpng supplied error
+handling and memory alloc/free functions.
+
+When libpng encounters an error, it expects to longjmp back
+to your routine.  Therefore, you will need to call setjmp and pass
+your png_jmpbuf(png_ptr).  If you read the file from different
+routines, you will need to update the jmpbuf field every time you enter
+a new routine that will call a png_*() function.
+
+See your documentation of setjmp/longjmp for your compiler for more
+information on setjmp/longjmp.  See the discussion on libpng error
+handling in the Customizing Libpng section below for more information
+on the libpng error handling.  If an error occurs, and libpng longjmp's
+back to your setjmp, you will want to call png_destroy_read_struct() to
+free any memory.
+
+    if (setjmp(png_jmpbuf(png_ptr)))
+    {
+        png_destroy_read_struct(&png_ptr, &info_ptr,
+           &end_info);
+        fclose(fp);
+        return (ERROR);
+    }
+
+If you would rather avoid the complexity of setjmp/longjmp issues,
+you can compile libpng with PNG_SETJMP_NOT_SUPPORTED, in which case
+errors will result in a call to PNG_ABORT() which defaults to abort().
+
+Now you need to set up the input code.  The default for libpng is to
+use the C function fread().  If you use this, you will need to pass a
+valid FILE * in the function png_init_io().  Be sure that the file is
+opened in binary mode.  If you wish to handle reading data in another
+way, you need not call the png_init_io() function, but you must then
+implement the libpng I/O methods discussed in the Customizing Libpng
+section below.
+
+    png_init_io(png_ptr, fp);
+
+If you had previously opened the file and read any of the signature from
+the beginning in order to see if this was a PNG file, you need to let
+libpng know that there are some bytes missing from the start of the file.
+
+    png_set_sig_bytes(png_ptr, number);
+
+Setting up callback code
+
+You can set up a callback function to handle any unknown chunks in the
+input stream. You must supply the function
+
+    read_chunk_callback(png_ptr ptr,
+         png_unknown_chunkp chunk);
+    {
+       /* The unknown chunk structure contains your
+          chunk data: */
+           png_byte name[5];
+           png_byte *data;
+           png_size_t size;
+       /* Note that libpng has already taken care of
+          the CRC handling */
+
+       /* put your code here.  Return one of the
+          following: */
+
+       return (-n); /* chunk had an error */
+       return (0); /* did not recognize */
+       return (n); /* success */
+    }
+
+(You can give your function another name that you like instead of
+"read_chunk_callback")
+
+To inform libpng about your function, use
+
+    png_set_read_user_chunk_fn(png_ptr, user_chunk_ptr,
+        read_chunk_callback);
+
+This names not only the callback function, but also a user pointer that
+you can retrieve with
+
+    png_get_user_chunk_ptr(png_ptr);
+
+At this point, you can set up a callback function that will be
+called after each row has been read, which you can use to control
+a progress meter or the like.  It's demonstrated in pngtest.c.
+You must supply a function
+
+    void read_row_callback(png_ptr ptr, png_uint_32 row,
+       int pass);
+    {
+      /* put your code here */
+    }
+
+(You can give it another name that you like instead of "read_row_callback")
+
+To inform libpng about your function, use
+
+    png_set_read_status_fn(png_ptr, read_row_callback);
+
+Width and height limits
+
+The PNG specification allows the width and height of an image to be as
+large as 2^31-1 (0x7fffffff), or about 2.147 billion rows and columns.
+Since very few applications really need to process such large images,
+we have imposed an arbitrary 1-million limit on rows and columns.
+Larger images will be rejected immediately with a png_error() call. If
+you wish to override this limit, you can use
+
+   png_set_user_limits(png_ptr, width_max, height_max);
+
+to set your own limits, or use width_max = height_max = 0x7fffffffL
+to allow all valid dimensions (libpng may reject some very large images
+anyway because of potential buffer overflow conditions).
+
+You should put this statement after you create the PNG structure and
+before calling png_read_info(), png_read_png(), or png_process_data().
+If you need to retrieve the limits that are being applied, use
+
+   width_max = png_get_user_width_max(png_ptr);
+   height_max = png_get_user_height_max(png_ptr);
+
+Unknown-chunk handling
+
+Now you get to set the way the library processes unknown chunks in the
+input PNG stream. Both known and unknown chunks will be read.  Normal
+behavior is that known chunks will be parsed into information in
+various info_ptr members; unknown chunks will be discarded. To change
+this, you can call:
+
+    png_set_keep_unknown_chunks(png_ptr, keep,
+        chunk_list, num_chunks);
+    keep       - 0: do not handle as unknown
+                 1: do not keep
+                 2: keep only if safe-to-copy
+                 3: keep even if unsafe-to-copy
+               You can use these definitions:
+                 PNG_HANDLE_CHUNK_AS_DEFAULT   0
+                 PNG_HANDLE_CHUNK_NEVER        1
+                 PNG_HANDLE_CHUNK_IF_SAFE      2
+                 PNG_HANDLE_CHUNK_ALWAYS       3
+    chunk_list - list of chunks affected (a byte string,
+                 five bytes per chunk, NULL or '\0' if
+                 num_chunks is 0)
+    num_chunks - number of chunks affected; if 0, all
+                 unknown chunks are affected.  If nonzero,
+                 only the chunks in the list are affected
+
+Unknown chunks declared in this way will be saved as raw data onto a
+list of png_unknown_chunk structures.  If a chunk that is normally
+known to libpng is named in the list, it will be handled as unknown,
+according to the "keep" directive.  If a chunk is named in successive
+instances of png_set_keep_unknown_chunks(), the final instance will
+take precedence.  The IHDR and IEND chunks should not be named in
+chunk_list; if they are, libpng will process them normally anyway.
+
+The high-level read interface
+
+At this point there are two ways to proceed; through the high-level
+read interface, or through a sequence of low-level read operations.
+You can use the high-level interface if (a) you are willing to read
+the entire image into memory, and (b) the input transformations
+you want to do are limited to the following set:
+
+    PNG_TRANSFORM_IDENTITY      No transformation
+    PNG_TRANSFORM_STRIP_16      Strip 16-bit samples to
+                                8 bits
+    PNG_TRANSFORM_STRIP_ALPHA   Discard the alpha channel
+    PNG_TRANSFORM_PACKING       Expand 1, 2 and 4-bit
+                                samples to bytes
+    PNG_TRANSFORM_PACKSWAP      Change order of packed
+                                pixels to LSB first
+    PNG_TRANSFORM_EXPAND        Perform set_expand()
+    PNG_TRANSFORM_INVERT_MONO   Invert monochrome images
+    PNG_TRANSFORM_SHIFT         Normalize pixels to the
+                                sBIT depth
+    PNG_TRANSFORM_BGR           Flip RGB to BGR, RGBA
+                                to BGRA
+    PNG_TRANSFORM_SWAP_ALPHA    Flip RGBA to ARGB or GA
+                                to AG
+    PNG_TRANSFORM_INVERT_ALPHA  Change alpha from opacity
+                                to transparency
+    PNG_TRANSFORM_SWAP_ENDIAN   Byte-swap 16-bit samples
+
+(This excludes setting a background color, doing gamma transformation,
+dithering, and setting filler.)  If this is the case, simply do this:
+
+    png_read_png(png_ptr, info_ptr, png_transforms, NULL)
+
+where png_transforms is an integer containing the logical OR of
+some set of transformation flags.  This call is equivalent to png_read_info(),
+followed the set of transformations indicated by the transform mask,
+then png_read_image(), and finally png_read_end().
+
+(The final parameter of this call is not yet used.  Someday it might point
+to transformation parameters required by some future input transform.)
+
+You must use png_transforms and not call any png_set_transform() functions
+when you use png_read_png().
+
+After you have called png_read_png(), you can retrieve the image data
+with
+
+   row_pointers = png_get_rows(png_ptr, info_ptr);
+
+where row_pointers is an array of pointers to the pixel data for each row:
+
+   png_bytep row_pointers[height];
+
+If you know your image size and pixel size ahead of time, you can allocate
+row_pointers prior to calling png_read_png() with
+
+   if (height > PNG_UINT_32_MAX/png_sizeof(png_byte))
+      png_error (png_ptr,
+         "Image is too tall to process in memory");
+   if (width > PNG_UINT_32_MAX/pixel_size)
+      png_error (png_ptr,
+         "Image is too wide to process in memory");
+   row_pointers = png_malloc(png_ptr,
+      height*png_sizeof(png_bytep));
+   for (int i=0; i<height, i++)
+      row_pointers[i]=png_malloc(png_ptr,
+         width*pixel_size);
+   png_set_rows(png_ptr, info_ptr, &row_pointers);
+
+Alternatively you could allocate your image in one big block and define
+row_pointers[i] to point into the proper places in your block.
+
+If you use png_set_rows(), the application is responsible for freeing
+row_pointers (and row_pointers[i], if they were separately allocated).
+
+If you don't allocate row_pointers ahead of time, png_read_png() will
+do it, and it'll be free'ed when you call png_destroy_*().
+
+The low-level read interface
+
+If you are going the low-level route, you are now ready to read all
+the file information up to the actual image data.  You do this with a
+call to png_read_info().
+
+    png_read_info(png_ptr, info_ptr);
+
+This will process all chunks up to but not including the image data.
+
+Querying the info structure
+
+Functions are used to get the information from the info_ptr once it
+has been read.  Note that these fields may not be completely filled
+in until png_read_end() has read the chunk data following the image.
+
+    png_get_IHDR(png_ptr, info_ptr, &width, &height,
+       &bit_depth, &color_type, &interlace_type,
+       &compression_type, &filter_method);
+
+    width          - holds the width of the image
+                     in pixels (up to 2^31).
+    height         - holds the height of the image
+                     in pixels (up to 2^31).
+    bit_depth      - holds the bit depth of one of the
+                     image channels.  (valid values are
+                     1, 2, 4, 8, 16 and depend also on
+                     the color_type.  See also
+                     significant bits (sBIT) below).
+    color_type     - describes which color/alpha channels
+                         are present.
+                     PNG_COLOR_TYPE_GRAY
+                        (bit depths 1, 2, 4, 8, 16)
+                     PNG_COLOR_TYPE_GRAY_ALPHA
+                        (bit depths 8, 16)
+                     PNG_COLOR_TYPE_PALETTE
+                        (bit depths 1, 2, 4, 8)
+                     PNG_COLOR_TYPE_RGB
+                        (bit_depths 8, 16)
+                     PNG_COLOR_TYPE_RGB_ALPHA
+                        (bit_depths 8, 16)
+
+                     PNG_COLOR_MASK_PALETTE
+                     PNG_COLOR_MASK_COLOR
+                     PNG_COLOR_MASK_ALPHA
+
+    filter_method  - (must be PNG_FILTER_TYPE_BASE
+                     for PNG 1.0, and can also be
+                     PNG_INTRAPIXEL_DIFFERENCING if
+                     the PNG datastream is embedded in
+                     a MNG-1.0 datastream)
+    compression_type - (must be PNG_COMPRESSION_TYPE_BASE
+                     for PNG 1.0)
+    interlace_type - (PNG_INTERLACE_NONE or
+                     PNG_INTERLACE_ADAM7)
+    Any or all of interlace_type, compression_type, of
+    filter_method can be NULL if you are
+    not interested in their values.
+
+    channels = png_get_channels(png_ptr, info_ptr);
+    channels       - number of channels of info for the
+                     color type (valid values are 1 (GRAY,
+                     PALETTE), 2 (GRAY_ALPHA), 3 (RGB),
+                     4 (RGB_ALPHA or RGB + filler byte))
+    rowbytes = png_get_rowbytes(png_ptr, info_ptr);
+    rowbytes       - number of bytes needed to hold a row
+
+    signature = png_get_signature(png_ptr, info_ptr);
+    signature      - holds the signature read from the
+                     file (if any).  The data is kept in
+                     the same offset it would be if the
+                     whole signature were read (i.e. if an
+                     application had already read in 4
+                     bytes of signature before starting
+                     libpng, the remaining 4 bytes would
+                     be in signature[4] through signature[7]
+                     (see png_set_sig_bytes())).
+
+
+    width            = png_get_image_width(png_ptr,
+                         info_ptr);
+    height           = png_get_image_height(png_ptr,
+                         info_ptr);
+    bit_depth        = png_get_bit_depth(png_ptr,
+                         info_ptr);
+    color_type       = png_get_color_type(png_ptr,
+                         info_ptr);
+    filter_method    = png_get_filter_type(png_ptr,
+                         info_ptr);
+    compression_type = png_get_compression_type(png_ptr,
+                         info_ptr);
+    interlace_type   = png_get_interlace_type(png_ptr,
+                         info_ptr);
+
+
+These are also important, but their validity depends on whether the chunk
+has been read.  The png_get_valid(png_ptr, info_ptr, PNG_INFO_<chunk>) and
+png_get_<chunk>(png_ptr, info_ptr, ...) functions return non-zero if the
+data has been read, or zero if it is missing.  The parameters to the
+png_get_<chunk> are set directly if they are simple data types, or a pointer
+into the info_ptr is returned for any complex types.
+
+    png_get_PLTE(png_ptr, info_ptr, &palette,
+                     &num_palette);
+    palette        - the palette for the file
+                     (array of png_color)
+    num_palette    - number of entries in the palette
+
+    png_get_gAMA(png_ptr, info_ptr, &gamma);
+    gamma          - the gamma the file is written
+                     at (PNG_INFO_gAMA)
+
+    png_get_sRGB(png_ptr, info_ptr, &srgb_intent);
+    srgb_intent    - the rendering intent (PNG_INFO_sRGB)
+                     The presence of the sRGB chunk
+                     means that the pixel data is in the
+                     sRGB color space.  This chunk also
+                     implies specific values of gAMA and
+                     cHRM.
+
+    png_get_iCCP(png_ptr, info_ptr, &name,
+       &compression_type, &profile, &proflen);
+    name            - The profile name.
+    compression     - The compression type; always
+                      PNG_COMPRESSION_TYPE_BASE for PNG 1.0.
+                      You may give NULL to this argument to
+                      ignore it.
+    profile         - International Color Consortium color
+                      profile data. May contain NULs.
+    proflen         - length of profile data in bytes.
+
+    png_get_sBIT(png_ptr, info_ptr, &sig_bit);
+    sig_bit        - the number of significant bits for
+                     (PNG_INFO_sBIT) each of the gray,
+                     red, green, and blue channels,
+                     whichever are appropriate for the
+                     given color type (png_color_16)
+
+    png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans,
+                     &trans_values);
+    trans          - array of transparent entries for
+                     palette (PNG_INFO_tRNS)
+    trans_values   - graylevel or color sample values of
+                     the single transparent color for
+                     non-paletted images (PNG_INFO_tRNS)
+    num_trans      - number of transparent entries
+                     (PNG_INFO_tRNS)
+
+    png_get_hIST(png_ptr, info_ptr, &hist);
+                     (PNG_INFO_hIST)
+    hist           - histogram of palette (array of
+                     png_uint_16)
+
+    png_get_tIME(png_ptr, info_ptr, &mod_time);
+    mod_time       - time image was last modified
+                    (PNG_VALID_tIME)
+
+    png_get_bKGD(png_ptr, info_ptr, &background);
+    background     - background color (PNG_VALID_bKGD)
+                     valid 16-bit red, green and blue
+                     values, regardless of color_type
+
+    num_comments   = png_get_text(png_ptr, info_ptr,
+                     &text_ptr, &num_text);
+    num_comments   - number of comments
+    text_ptr       - array of png_text holding image
+                     comments
+    text_ptr[i].compression - type of compression used
+                 on "text" PNG_TEXT_COMPRESSION_NONE
+                           PNG_TEXT_COMPRESSION_zTXt
+                           PNG_ITXT_COMPRESSION_NONE
+                           PNG_ITXT_COMPRESSION_zTXt
+    text_ptr[i].key   - keyword for comment.  Must contain
+                         1-79 characters.
+    text_ptr[i].text  - text comments for current
+                         keyword.  Can be empty.
+    text_ptr[i].text_length - length of text string,
+                 after decompression, 0 for iTXt
+    text_ptr[i].itxt_length - length of itxt string,
+                 after decompression, 0 for tEXt/zTXt
+    text_ptr[i].lang  - language of comment (empty
+                         string for unknown).
+    text_ptr[i].lang_key  - keyword in UTF-8
+                         (empty string for unknown).
+    num_text       - number of comments (same as
+                     num_comments; you can put NULL here
+                     to avoid the duplication)
+    Note while png_set_text() will accept text, language,
+    and translated keywords that can be NULL pointers, the
+    structure returned by png_get_text will always contain
+    regular zero-terminated C strings.  They might be
+    empty strings but they will never be NULL pointers.
+
+    num_spalettes = png_get_sPLT(png_ptr, info_ptr,
+       &palette_ptr);
+    palette_ptr    - array of palette structures holding
+                     contents of one or more sPLT chunks
+                     read.
+    num_spalettes  - number of sPLT chunks read.
+
+    png_get_oFFs(png_ptr, info_ptr, &offset_x, &offset_y,
+       &unit_type);
+    offset_x       - positive offset from the left edge
+                     of the screen
+    offset_y       - positive offset from the top edge
+                     of the screen
+    unit_type      - PNG_OFFSET_PIXEL, PNG_OFFSET_MICROMETER
+
+    png_get_pHYs(png_ptr, info_ptr, &res_x, &res_y,
+       &unit_type);
+    res_x          - pixels/unit physical resolution in
+                     x direction
+    res_y          - pixels/unit physical resolution in
+                     x direction
+    unit_type      - PNG_RESOLUTION_UNKNOWN,
+                     PNG_RESOLUTION_METER
+
+    png_get_sCAL(png_ptr, info_ptr, &unit, &width,
+       &height)
+    unit        - physical scale units (an integer)
+    width       - width of a pixel in physical scale units
+    height      - height of a pixel in physical scale units
+                 (width and height are doubles)
+
+    png_get_sCAL_s(png_ptr, info_ptr, &unit, &width,
+       &height)
+    unit        - physical scale units (an integer)
+    width       - width of a pixel in physical scale units
+    height      - height of a pixel in physical scale units
+                 (width and height are strings like "2.54")
+
+    num_unknown_chunks = png_get_unknown_chunks(png_ptr,
+       info_ptr, &unknowns)
+    unknowns          - array of png_unknown_chunk
+                        structures holding unknown chunks
+    unknowns[i].name  - name of unknown chunk
+    unknowns[i].data  - data of unknown chunk
+    unknowns[i].size  - size of unknown chunk's data
+    unknowns[i].location - position of chunk in file
+
+    The value of "i" corresponds to the order in which the
+    chunks were read from the PNG file or inserted with the
+    png_set_unknown_chunks() function.
+
+The data from the pHYs chunk can be retrieved in several convenient
+forms:
+
+    res_x = png_get_x_pixels_per_meter(png_ptr,
+       info_ptr)
+    res_y = png_get_y_pixels_per_meter(png_ptr,
+       info_ptr)
+    res_x_and_y = png_get_pixels_per_meter(png_ptr,
+       info_ptr)
+    res_x = png_get_x_pixels_per_inch(png_ptr,
+       info_ptr)
+    res_y = png_get_y_pixels_per_inch(png_ptr,
+       info_ptr)
+    res_x_and_y = png_get_pixels_per_inch(png_ptr,
+       info_ptr)
+    aspect_ratio = png_get_pixel_aspect_ratio(png_ptr,
+       info_ptr)
+
+   (Each of these returns 0 [signifying "unknown"] if
+       the data is not present or if res_x is 0;
+       res_x_and_y is 0 if res_x != res_y)
+
+The data from the oFFs chunk can be retrieved in several convenient
+forms:
+
+    x_offset = png_get_x_offset_microns(png_ptr, info_ptr);
+    y_offset = png_get_y_offset_microns(png_ptr, info_ptr);
+    x_offset = png_get_x_offset_inches(png_ptr, info_ptr);
+    y_offset = png_get_y_offset_inches(png_ptr, info_ptr);
+
+   (Each of these returns 0 [signifying "unknown" if both
+       x and y are 0] if the data is not present or if the
+       chunk is present but the unit is the pixel)
+
+For more information, see the png_info definition in png.h and the
+PNG specification for chunk contents.  Be careful with trusting
+rowbytes, as some of the transformations could increase the space
+needed to hold a row (expand, filler, gray_to_rgb, etc.).
+See png_read_update_info(), below.
+
+A quick word about text_ptr and num_text.  PNG stores comments in
+keyword/text pairs, one pair per chunk, with no limit on the number
+of text chunks, and a 2^31 byte limit on their size.  While there are
+suggested keywords, there is no requirement to restrict the use to these
+strings.  It is strongly suggested that keywords and text be sensible
+to humans (that's the point), so don't use abbreviations.  Non-printing
+symbols are not allowed.  See the PNG specification for more details.
+There is also no requirement to have text after the keyword.
+
+Keywords should be limited to 79 Latin-1 characters without leading or
+trailing spaces, but non-consecutive spaces are allowed within the
+keyword.  It is possible to have the same keyword any number of times.
+The text_ptr is an array of png_text structures, each holding a
+pointer to a language string, a pointer to a keyword and a pointer to
+a text string.  The text string, language code, and translated
+keyword may be empty or NULL pointers.  The keyword/text
+pairs are put into the array in the order that they are received.
+However, some or all of the text chunks may be after the image, so, to
+make sure you have read all the text chunks, don't mess with these
+until after you read the stuff after the image.  This will be
+mentioned again below in the discussion that goes with png_read_end().
+
+Input transformations
+
+After you've read the header information, you can set up the library
+to handle any special transformations of the image data.  The various
+ways to transform the data will be described in the order that they
+should occur.  This is important, as some of these change the color
+type and/or bit depth of the data, and some others only work on
+certain color types and bit depths.  Even though each transformation
+checks to see if it has data that it can do something with, you should
+make sure to only enable a transformation if it will be valid for the
+data.  For example, don't swap red and blue on grayscale data.
+
+The colors used for the background and transparency values should be
+supplied in the same format/depth as the current image data.  They
+are stored in the same format/depth as the image data in a bKGD or tRNS
+chunk, so this is what libpng expects for this data.  The colors are
+transformed to keep in sync with the image data when an application
+calls the png_read_update_info() routine (see below).
+
+Data will be decoded into the supplied row buffers packed into bytes
+unless the library has been told to transform it into another format.
+For example, 4 bit/pixel paletted or grayscale data will be returned
+2 pixels/byte with the leftmost pixel in the high-order bits of the
+byte, unless png_set_packing() is called.  8-bit RGB data will be stored
+in RGB RGB RGB format unless png_set_filler() or png_set_add_alpha()
+is called to insert filler bytes, either before or after each RGB triplet.
+16-bit RGB data will be returned RRGGBB RRGGBB, with the most significant
+byte of the color value first, unless png_set_strip_16() is called to
+transform it to regular RGB RGB triplets, or png_set_filler() or
+png_set_add alpha() is called to insert filler bytes, either before or
+after each RRGGBB triplet.  Similarly, 8-bit or 16-bit grayscale data can
+be modified with
+png_set_filler(), png_set_add_alpha(), or png_set_strip_16().
+
+The following code transforms grayscale images of less than 8 to 8 bits,
+changes paletted images to RGB, and adds a full alpha channel if there is
+transparency information in a tRNS chunk.  This is most useful on
+grayscale images with bit depths of 2 or 4 or if there is a multiple-image
+viewing application that wishes to treat all images in the same way.
+
+    if (color_type == PNG_COLOR_TYPE_PALETTE)
+        png_set_palette_to_rgb(png_ptr);
+
+    if (color_type == PNG_COLOR_TYPE_GRAY &&
+        bit_depth < 8) png_set_gray_1_2_4_to_8(png_ptr);
+
+    if (png_get_valid(png_ptr, info_ptr,
+        PNG_INFO_tRNS)) png_set_tRNS_to_alpha(png_ptr);
+
+These three functions are actually aliases for png_set_expand(), added
+in libpng version 1.0.4, with the function names expanded to improve code
+readability.  In some future version they may actually do different
+things.
+
+PNG can have files with 16 bits per channel.  If you only can handle
+8 bits per channel, this will strip the pixels down to 8 bit.
+
+    if (bit_depth == 16)
+        png_set_strip_16(png_ptr);
+
+If, for some reason, you don't need the alpha channel on an image,
+and you want to remove it rather than combining it with the background
+(but the image author certainly had in mind that you *would* combine
+it with the background, so that's what you should probably do):
+
+    if (color_type & PNG_COLOR_MASK_ALPHA)
+        png_set_strip_alpha(png_ptr);
+
+In PNG files, the alpha channel in an image
+is the level of opacity.  If you need the alpha channel in an image to
+be the level of transparency instead of opacity, you can invert the
+alpha channel (or the tRNS chunk data) after it's read, so that 0 is
+fully opaque and 255 (in 8-bit or paletted images) or 65535 (in 16-bit
+images) is fully transparent, with
+
+    png_set_invert_alpha(png_ptr);
+
+PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as
+they can, resulting in, for example, 8 pixels per byte for 1 bit
+files.  This code expands to 1 pixel per byte without changing the
+values of the pixels:
+
+    if (bit_depth < 8)
+        png_set_packing(png_ptr);
+
+PNG files have possible bit depths of 1, 2, 4, 8, and 16.  All pixels
+stored in a PNG image have been "scaled" or "shifted" up to the next
+higher possible bit depth (e.g. from 5 bits/sample in the range [0,31] to
+8 bits/sample in the range [0, 255]).  However, it is also possible to
+convert the PNG pixel data back to the original bit depth of the image.
+This call reduces the pixels back down to the original bit depth:
+
+    png_color_8p sig_bit;
+
+    if (png_get_sBIT(png_ptr, info_ptr, &sig_bit))
+        png_set_shift(png_ptr, sig_bit);
+
+PNG files store 3-color pixels in red, green, blue order.  This code
+changes the storage of the pixels to blue, green, red:
+
+    if (color_type == PNG_COLOR_TYPE_RGB ||
+        color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+        png_set_bgr(png_ptr);
+
+PNG files store RGB pixels packed into 3 or 6 bytes. This code expands them
+into 4 or 8 bytes for windowing systems that need them in this format:
+
+    if (color_type == PNG_COLOR_TYPE_RGB)
+        png_set_filler(png_ptr, filler, PNG_FILLER_BEFORE);
+
+where "filler" is the 8 or 16-bit number to fill with, and the location is
+either PNG_FILLER_BEFORE or PNG_FILLER_AFTER, depending upon whether
+you want the filler before the RGB or after.  This transformation
+does not affect images that already have full alpha channels.  To add an
+opaque alpha channel, use filler=0xff or 0xffff and PNG_FILLER_AFTER which
+will generate RGBA pixels.
+
+Note that png_set_filler() does not change the color type.  If you want
+to do that, you can add a true alpha channel with
+
+    if (color_type == PNG_COLOR_TYPE_RGB ||
+           color_type == PNG_COLOR_TYPE_GRAY)
+    png_set_add_alpha(png_ptr, filler, PNG_FILLER_AFTER);
+
+where "filler" contains the alpha value to assign to each pixel.
+This function was added in libpng-1.2.7.
+
+If you are reading an image with an alpha channel, and you need the
+data as ARGB instead of the normal PNG format RGBA:
+
+    if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+        png_set_swap_alpha(png_ptr);
+
+For some uses, you may want a grayscale image to be represented as
+RGB.  This code will do that conversion:
+
+    if (color_type == PNG_COLOR_TYPE_GRAY ||
+        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+          png_set_gray_to_rgb(png_ptr);
+
+Conversely, you can convert an RGB or RGBA image to grayscale or grayscale
+with alpha.
+
+    if (color_type == PNG_COLOR_TYPE_RGB ||
+        color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+          png_set_rgb_to_gray_fixed(png_ptr, error_action,
+             int red_weight, int green_weight);
+
+    error_action = 1: silently do the conversion
+    error_action = 2: issue a warning if the original
+                      image has any pixel where
+                      red != green or red != blue
+    error_action = 3: issue an error and abort the
+                      conversion if the original
+                      image has any pixel where
+                      red != green or red != blue
+
+    red_weight:       weight of red component times 100000
+    green_weight:     weight of green component times 100000
+                      If either weight is negative, default
+                      weights (21268, 71514) are used.
+
+If you have set error_action = 1 or 2, you can
+later check whether the image really was gray, after processing
+the image rows, with the png_get_rgb_to_gray_status(png_ptr) function.
+It will return a png_byte that is zero if the image was gray or
+1 if there were any non-gray pixels.  bKGD and sBIT data
+will be silently converted to grayscale, using the green channel
+data, regardless of the error_action setting.
+
+With red_weight+green_weight<=100000,
+the normalized graylevel is computed:
+
+    int rw = red_weight * 65536;
+    int gw = green_weight * 65536;
+    int bw = 65536 - (rw + gw);
+    gray = (rw*red + gw*green + bw*blue)/65536;
+
+The default values approximate those recommended in the Charles
+Poynton's Color FAQ, <http://www.inforamp.net/~poynton/>
+Copyright (c) 1998-01-04 Charles Poynton <poynton at inforamp.net>
+
+    Y = 0.212671 * R + 0.715160 * G + 0.072169 * B
+
+Libpng approximates this with
+
+    Y = 0.21268 * R    + 0.7151 * G    + 0.07217 * B
+
+which can be expressed with integers as
+
+    Y = (6969 * R + 23434 * G + 2365 * B)/32768
+
+The calculation is done in a linear colorspace, if the image gamma
+is known.
+
+If you have a grayscale and you are using png_set_expand_depth(),
+png_set_expand(), or png_set_gray_to_rgb to change to truecolor or to
+a higher bit-depth, you must either supply the background color as a gray
+value at the original file bit-depth (need_expand = 1) or else supply the
+background color as an RGB triplet at the final, expanded bit depth
+(need_expand = 0).  Similarly, if you are reading a paletted image, you
+must either supply the background color as a palette index (need_expand = 1)
+or as an RGB triplet that may or may not be in the palette (need_expand = 0).
+
+    png_color_16 my_background;
+    png_color_16p image_background;
+
+    if (png_get_bKGD(png_ptr, info_ptr, &image_background))
+        png_set_background(png_ptr, image_background,
+          PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
+    else
+        png_set_background(png_ptr, &my_background,
+          PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
+
+The png_set_background() function tells libpng to composite images
+with alpha or simple transparency against the supplied background
+color.  If the PNG file contains a bKGD chunk (PNG_INFO_bKGD valid),
+you may use this color, or supply another color more suitable for
+the current display (e.g., the background color from a web page).  You
+need to tell libpng whether the color is in the gamma space of the
+display (PNG_BACKGROUND_GAMMA_SCREEN for colors you supply), the file
+(PNG_BACKGROUND_GAMMA_FILE for colors from the bKGD chunk), or one
+that is neither of these gammas (PNG_BACKGROUND_GAMMA_UNIQUE - I don't
+know why anyone would use this, but it's here).
+
+To properly display PNG images on any kind of system, the application needs
+to know what the display gamma is.  Ideally, the user will know this, and
+the application will allow them to set it.  One method of allowing the user
+to set the display gamma separately for each system is to check for a
+SCREEN_GAMMA or DISPLAY_GAMMA environment variable, which will hopefully be
+correctly set.
+
+Note that display_gamma is the overall gamma correction required to produce
+pleasing results, which depends on the lighting conditions in the surrounding
+environment.  In a dim or brightly lit room, no compensation other than
+the physical gamma exponent of the monitor is needed, while in a dark room
+a slightly smaller exponent is better.
+
+   double gamma, screen_gamma;
+
+   if (/* We have a user-defined screen
+       gamma value */)
+   {
+      screen_gamma = user_defined_screen_gamma;
+   }
+   /* One way that applications can share the same
+      screen gamma value */
+   else if ((gamma_str = getenv("SCREEN_GAMMA"))
+      != NULL)
+   {
+      screen_gamma = (double)atof(gamma_str);
+   }
+   /* If we don't have another value */
+   else
+   {
+      screen_gamma = 2.2; /* A good guess for a
+           PC monitor in a bright office or a dim room */
+      screen_gamma = 2.0; /* A good guess for a
+           PC monitor in a dark room */
+      screen_gamma = 1.7 or 1.0;  /* A good
+           guess for Mac systems */
+   }
+
+The png_set_gamma() function handles gamma transformations of the data.
+Pass both the file gamma and the current screen_gamma.  If the file does
+not have a gamma value, you can pass one anyway if you have an idea what
+it is (usually 0.45455 is a good guess for GIF images on PCs).  Note
+that file gammas are inverted from screen gammas.  See the discussions
+on gamma in the PNG specification for an excellent description of what
+gamma is, and why all applications should support it.  It is strongly
+recommended that PNG viewers support gamma correction.
+
+   if (png_get_gAMA(png_ptr, info_ptr, &gamma))
+      png_set_gamma(png_ptr, screen_gamma, gamma);
+   else
+      png_set_gamma(png_ptr, screen_gamma, 0.45455);
+
+If you need to reduce an RGB file to a paletted file, or if a paletted
+file has more entries then will fit on your screen, png_set_dither()
+will do that.  Note that this is a simple match dither that merely
+finds the closest color available.  This should work fairly well with
+optimized palettes, and fairly badly with linear color cubes.  If you
+pass a palette that is larger then maximum_colors, the file will
+reduce the number of colors in the palette so it will fit into
+maximum_colors.  If there is a histogram, it will use it to make
+more intelligent choices when reducing the palette.  If there is no
+histogram, it may not do as good a job.
+
+   if (color_type & PNG_COLOR_MASK_COLOR)
+   {
+      if (png_get_valid(png_ptr, info_ptr,
+         PNG_INFO_PLTE))
+      {
+         png_uint_16p histogram = NULL;
+
+         png_get_hIST(png_ptr, info_ptr,
+            &histogram);
+         png_set_dither(png_ptr, palette, num_palette,
+            max_screen_colors, histogram, 1);
+      }
+      else
+      {
+         png_color std_color_cube[MAX_SCREEN_COLORS] =
+            { ... colors ... };
+
+         png_set_dither(png_ptr, std_color_cube,
+            MAX_SCREEN_COLORS, MAX_SCREEN_COLORS,
+            NULL,0);
+      }
+   }
+
+PNG files describe monochrome as black being zero and white being one.
+The following code will reverse this (make black be one and white be
+zero):
+
+   if (bit_depth == 1 && color_type == PNG_COLOR_TYPE_GRAY)
+      png_set_invert_mono(png_ptr);
+
+This function can also be used to invert grayscale and gray-alpha images:
+
+   if (color_type == PNG_COLOR_TYPE_GRAY ||
+        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      png_set_invert_mono(png_ptr);
+
+PNG files store 16 bit pixels in network byte order (big-endian,
+ie. most significant bits first).  This code changes the storage to the
+other way (little-endian, i.e. least significant bits first, the
+way PCs store them):
+
+    if (bit_depth == 16)
+        png_set_swap(png_ptr);
+
+If you are using packed-pixel images (1, 2, or 4 bits/pixel), and you
+need to change the order the pixels are packed into bytes, you can use:
+
+    if (bit_depth < 8)
+       png_set_packswap(png_ptr);
+
+Finally, you can write your own transformation function if none of
+the existing ones meets your needs.  This is done by setting a callback
+with
+
+    png_set_read_user_transform_fn(png_ptr,
+       read_transform_fn);
+
+You must supply the function
+
+    void read_transform_fn(png_ptr ptr, row_info_ptr
+       row_info, png_bytep data)
+
+See pngtest.c for a working example.  Your function will be called
+after all of the other transformations have been processed.
+
+You can also set up a pointer to a user structure for use by your
+callback function, and you can inform libpng that your transform
+function will change the number of channels or bit depth with the
+function
+
+    png_set_user_transform_info(png_ptr, user_ptr,
+       user_depth, user_channels);
+
+The user's application, not libpng, is responsible for allocating and
+freeing any memory required for the user structure.
+
+You can retrieve the pointer via the function
+png_get_user_transform_ptr().  For example:
+
+    voidp read_user_transform_ptr =
+       png_get_user_transform_ptr(png_ptr);
+
+The last thing to handle is interlacing; this is covered in detail below,
+but you must call the function here if you want libpng to handle expansion
+of the interlaced image.
+
+    number_of_passes = png_set_interlace_handling(png_ptr);
+
+After setting the transformations, libpng can update your png_info
+structure to reflect any transformations you've requested with this
+call.  This is most useful to update the info structure's rowbytes
+field so you can use it to allocate your image memory.  This function
+will also update your palette with the correct screen_gamma and
+background if these have been given with the calls above.
+
+    png_read_update_info(png_ptr, info_ptr);
+
+After you call png_read_update_info(), you can allocate any
+memory you need to hold the image.  The row data is simply
+raw byte data for all forms of images.  As the actual allocation
+varies among applications, no example will be given.  If you
+are allocating one large chunk, you will need to build an
+array of pointers to each row, as it will be needed for some
+of the functions below.
+
+Reading image data
+
+After you've allocated memory, you can read the image data.
+The simplest way to do this is in one function call.  If you are
+allocating enough memory to hold the whole image, you can just
+call png_read_image() and libpng will read in all the image data
+and put it in the memory area supplied.  You will need to pass in
+an array of pointers to each row.
+
+This function automatically handles interlacing, so you don't need
+to call png_set_interlace_handling() or call this function multiple
+times, or any of that other stuff necessary with png_read_rows().
+
+   png_read_image(png_ptr, row_pointers);
+
+where row_pointers is:
+
+   png_bytep row_pointers[height];
+
+You can point to void or char or whatever you use for pixels.
+
+If you don't want to read in the whole image at once, you can
+use png_read_rows() instead.  If there is no interlacing (check
+interlace_type == PNG_INTERLACE_NONE), this is simple:
+
+    png_read_rows(png_ptr, row_pointers, NULL,
+       number_of_rows);
+
+where row_pointers is the same as in the png_read_image() call.
+
+If you are doing this just one row at a time, you can do this with
+a single row_pointer instead of an array of row_pointers:
+
+    png_bytep row_pointer = row;
+    png_read_row(png_ptr, row_pointer, NULL);
+
+If the file is interlaced (interlace_type != 0 in the IHDR chunk), things
+get somewhat harder.  The only current (PNG Specification version 1.2)
+interlacing type for PNG is (interlace_type == PNG_INTERLACE_ADAM7)
+is a somewhat complicated 2D interlace scheme, known as Adam7, that
+breaks down an image into seven smaller images of varying size, based
+on an 8x8 grid.
+
+libpng can fill out those images or it can give them to you "as is".
+If you want them filled out, there are two ways to do that.  The one
+mentioned in the PNG specification is to expand each pixel to cover
+those pixels that have not been read yet (the "rectangle" method).
+This results in a blocky image for the first pass, which gradually
+smooths out as more pixels are read.  The other method is the "sparkle"
+method, where pixels are drawn only in their final locations, with the
+rest of the image remaining whatever colors they were initialized to
+before the start of the read.  The first method usually looks better,
+but tends to be slower, as there are more pixels to put in the rows.
+
+If you don't want libpng to handle the interlacing details, just call
+png_read_rows() seven times to read in all seven images.  Each of the
+images is a valid image by itself, or they can all be combined on an
+8x8 grid to form a single image (although if you intend to combine them
+you would be far better off using the libpng interlace handling).
+
+The first pass will return an image 1/8 as wide as the entire image
+(every 8th column starting in column 0) and 1/8 as high as the original
+(every 8th row starting in row 0), the second will be 1/8 as wide
+(starting in column 4) and 1/8 as high (also starting in row 0).  The
+third pass will be 1/4 as wide (every 4th pixel starting in column 0) and
+1/8 as high (every 8th row starting in row 4), and the fourth pass will
+be 1/4 as wide and 1/4 as high (every 4th column starting in column 2,
+and every 4th row starting in row 0).  The fifth pass will return an
+image 1/2 as wide, and 1/4 as high (starting at column 0 and row 2),
+while the sixth pass will be 1/2 as wide and 1/2 as high as the original
+(starting in column 1 and row 0).  The seventh and final pass will be as
+wide as the original, and 1/2 as high, containing all of the odd
+numbered scanlines.  Phew!
+
+If you want libpng to expand the images, call this before calling
+png_start_read_image() or png_read_update_info():
+
+    if (interlace_type == PNG_INTERLACE_ADAM7)
+        number_of_passes
+           = png_set_interlace_handling(png_ptr);
+
+This will return the number of passes needed.  Currently, this
+is seven, but may change if another interlace type is added.
+This function can be called even if the file is not interlaced,
+where it will return one pass.
+
+If you are not going to display the image after each pass, but are
+going to wait until the entire image is read in, use the sparkle
+effect.  This effect is faster and the end result of either method
+is exactly the same.  If you are planning on displaying the image
+after each pass, the "rectangle" effect is generally considered the
+better looking one.
+
+If you only want the "sparkle" effect, just call png_read_rows() as
+normal, with the third parameter NULL.  Make sure you make pass over
+the image number_of_passes times, and you don't change the data in the
+rows between calls.  You can change the locations of the data, just
+not the data.  Each pass only writes the pixels appropriate for that
+pass, and assumes the data from previous passes is still valid.
+
+    png_read_rows(png_ptr, row_pointers, NULL,
+       number_of_rows);
+
+If you only want the first effect (the rectangles), do the same as
+before except pass the row buffer in the third parameter, and leave
+the second parameter NULL.
+
+    png_read_rows(png_ptr, NULL, row_pointers,
+       number_of_rows);
+
+Finishing a sequential read
+
+After you are finished reading the image through either the high- or
+low-level interfaces, you can finish reading the file.  If you are
+interested in comments or time, which may be stored either before or
+after the image data, you should pass the separate png_info struct if
+you want to keep the comments from before and after the image
+separate.  If you are not interested, you can pass NULL.
+
+   png_read_end(png_ptr, end_info);
+
+When you are done, you can free all memory allocated by libpng like this:
+
+   png_destroy_read_struct(&png_ptr, &info_ptr,
+       &end_info);
+
+It is also possible to individually free the info_ptr members that
+point to libpng-allocated storage with the following function:
+
+    png_free_data(png_ptr, info_ptr, mask, seq)
+    mask - identifies data to be freed, a mask
+           containing the logical OR of one or
+           more of
+             PNG_FREE_PLTE, PNG_FREE_TRNS,
+             PNG_FREE_HIST, PNG_FREE_ICCP,
+             PNG_FREE_PCAL, PNG_FREE_ROWS,
+             PNG_FREE_SCAL, PNG_FREE_SPLT,
+             PNG_FREE_TEXT, PNG_FREE_UNKN,
+           or simply PNG_FREE_ALL
+    seq  - sequence number of item to be freed
+           (-1 for all items)
+
+This function may be safely called when the relevant storage has
+already been freed, or has not yet been allocated, or was allocated
+by the user and not by libpng,  and will in those
+cases do nothing.  The "seq" parameter is ignored if only one item
+of the selected data type, such as PLTE, is allowed.  If "seq" is not
+-1, and multiple items are allowed for the data type identified in
+the mask, such as text or sPLT, only the n'th item in the structure
+is freed, where n is "seq".
+
+The default behavior is only to free data that was allocated internally
+by libpng.  This can be changed, so that libpng will not free the data,
+or so that it will free data that was allocated by the user with png_malloc()
+or png_zalloc() and passed in via a png_set_*() function, with
+
+    png_data_freer(png_ptr, info_ptr, freer, mask)
+    mask   - which data elements are affected
+             same choices as in png_free_data()
+    freer  - one of
+               PNG_DESTROY_WILL_FREE_DATA
+               PNG_SET_WILL_FREE_DATA
+               PNG_USER_WILL_FREE_DATA
+
+This function only affects data that has already been allocated.
+You can call this function after reading the PNG data but before calling
+any png_set_*() functions, to control whether the user or the png_set_*()
+function is responsible for freeing any existing data that might be present,
+and again after the png_set_*() functions to control whether the user
+or png_destroy_*() is supposed to free the data.  When the user assumes
+responsibility for libpng-allocated data, the application must use
+png_free() to free it, and when the user transfers responsibility to libpng
+for data that the user has allocated, the user must have used png_malloc()
+or png_zalloc() to allocate it.
+
+If you allocated your row_pointers in a single block, as suggested above in
+the description of the high level read interface, you must not transfer
+responsibility for freeing it to the png_set_rows or png_read_destroy function,
+because they would also try to free the individual row_pointers[i].
+
+If you allocated text_ptr.text, text_ptr.lang, and text_ptr.translated_keyword
+separately, do not transfer responsibility for freeing text_ptr to libpng,
+because when libpng fills a png_text structure it combines these members with
+the key member, and png_free_data() will free only text_ptr.key.  Similarly,
+if you transfer responsibility for free'ing text_ptr from libpng to your
+application, your application must not separately free those members.
+
+The png_free_data() function will turn off the "valid" flag for anything
+it frees.  If you need to turn the flag off for a chunk that was freed by your
+application instead of by libpng, you can use
+
+    png_set_invalid(png_ptr, info_ptr, mask);
+    mask - identifies the chunks to be made invalid,
+           containing the logical OR of one or
+           more of
+             PNG_INFO_gAMA, PNG_INFO_sBIT,
+             PNG_INFO_cHRM, PNG_INFO_PLTE,
+             PNG_INFO_tRNS, PNG_INFO_bKGD,
+             PNG_INFO_hIST, PNG_INFO_pHYs,
+             PNG_INFO_oFFs, PNG_INFO_tIME,
+             PNG_INFO_pCAL, PNG_INFO_sRGB,
+             PNG_INFO_iCCP, PNG_INFO_sPLT,
+             PNG_INFO_sCAL, PNG_INFO_IDAT
+
+For a more compact example of reading a PNG image, see the file example.c.
+
+Reading PNG files progressively
+
+The progressive reader is slightly different then the non-progressive
+reader.  Instead of calling png_read_info(), png_read_rows(), and
+png_read_end(), you make one call to png_process_data(), which calls
+callbacks when it has the info, a row, or the end of the image.  You
+set up these callbacks with png_set_progressive_read_fn().  You don't
+have to worry about the input/output functions of libpng, as you are
+giving the library the data directly in png_process_data().  I will
+assume that you have read the section on reading PNG files above,
+so I will only highlight the differences (although I will show
+all of the code).
+
+png_structp png_ptr;
+png_infop info_ptr;
+
+ /*  An example code fragment of how you would
+     initialize the progressive reader in your
+     application. */
+ int
+ initialize_png_reader()
+ {
+    png_ptr = png_create_read_struct
+        (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+         user_error_fn, user_warning_fn);
+    if (!png_ptr)
+        return (ERROR);
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr)
+    {
+        png_destroy_read_struct(&png_ptr, (png_infopp)NULL,
+           (png_infopp)NULL);
+        return (ERROR);
+    }
+
+    if (setjmp(png_jmpbuf(png_ptr)))
+    {
+        png_destroy_read_struct(&png_ptr, &info_ptr,
+           (png_infopp)NULL);
+        return (ERROR);
+    }
+
+    /* This one's new.  You can provide functions
+       to be called when the header info is valid,
+       when each row is completed, and when the image
+       is finished.  If you aren't using all functions,
+       you can specify NULL parameters.  Even when all
+       three functions are NULL, you need to call
+       png_set_progressive_read_fn().  You can use
+       any struct as the user_ptr (cast to a void pointer
+       for the function call), and retrieve the pointer
+       from inside the callbacks using the function
+
+          png_get_progressive_ptr(png_ptr);
+
+       which will return a void pointer, which you have
+       to cast appropriately.
+     */
+    png_set_progressive_read_fn(png_ptr, (void *)user_ptr,
+        info_callback, row_callback, end_callback);
+
+    return 0;
+ }
+
+ /* A code fragment that you call as you receive blocks
+   of data */
+ int
+ process_data(png_bytep buffer, png_uint_32 length)
+ {
+    if (setjmp(png_jmpbuf(png_ptr)))
+    {
+        png_destroy_read_struct(&png_ptr, &info_ptr,
+           (png_infopp)NULL);
+        return (ERROR);
+    }
+
+    /* This one's new also.  Simply give it a chunk
+       of data from the file stream (in order, of
+       course).  On machines with segmented memory
+       models machines, don't give it any more than
+       64K.  The library seems to run fine with sizes
+       of 4K. Although you can give it much less if
+       necessary (I assume you can give it chunks of
+       1 byte, I haven't tried less then 256 bytes
+       yet).  When this function returns, you may
+       want to display any rows that were generated
+       in the row callback if you don't already do
+       so there.
+     */
+    png_process_data(png_ptr, info_ptr, buffer, length);
+    return 0;
+ }
+
+ /* This function is called (as set by
+    png_set_progressive_read_fn() above) when enough data
+    has been supplied so all of the header has been
+    read.
+ */
+ void
+ info_callback(png_structp png_ptr, png_infop info)
+ {
+    /* Do any setup here, including setting any of
+       the transformations mentioned in the Reading
+       PNG files section.  For now, you _must_ call
+       either png_start_read_image() or
+       png_read_update_info() after all the
+       transformations are set (even if you don't set
+       any).  You may start getting rows before
+       png_process_data() returns, so this is your
+       last chance to prepare for that.
+     */
+ }
+
+ /* This function is called when each row of image
+    data is complete */
+ void
+ row_callback(png_structp png_ptr, png_bytep new_row,
+    png_uint_32 row_num, int pass)
+ {
+    /* If the image is interlaced, and you turned
+       on the interlace handler, this function will
+       be called for every row in every pass.  Some
+       of these rows will not be changed from the
+       previous pass.  When the row is not changed,
+       the new_row variable will be NULL.  The rows
+       and passes are called in order, so you don't
+       really need the row_num and pass, but I'm
+       supplying them because it may make your life
+       easier.
+
+       For the non-NULL rows of interlaced images,
+       you must call png_progressive_combine_row()
+       passing in the row and the old row.  You can
+       call this function for NULL rows (it will just
+       return) and for non-interlaced images (it just
+       does the memcpy for you) if it will make the
+       code easier.  Thus, you can just do this for
+       all cases:
+     */
+
+        png_progressive_combine_row(png_ptr, old_row,
+          new_row);
+
+    /* where old_row is what was displayed for
+       previously for the row.  Note that the first
+       pass (pass == 0, really) will completely cover
+       the old row, so the rows do not have to be
+       initialized.  After the first pass (and only
+       for interlaced images), you will have to pass
+       the current row, and the function will combine
+       the old row and the new row.
+    */
+ }
+
+ void
+ end_callback(png_structp png_ptr, png_infop info)
+ {
+    /* This function is called after the whole image
+       has been read, including any chunks after the
+       image (up to and including the IEND).  You
+       will usually have the same info chunk as you
+       had in the header, although some data may have
+       been added to the comments and time fields.
+
+       Most people won't do much here, perhaps setting
+       a flag that marks the image as finished.
+     */
+ }
+
+
+
+IV. Writing
+
+Much of this is very similar to reading.  However, everything of
+importance is repeated here, so you won't have to constantly look
+back up in the reading section to understand writing.
+
+Setup
+
+You will want to do the I/O initialization before you get into libpng,
+so if it doesn't work, you don't have anything to undo. If you are not
+using the standard I/O functions, you will need to replace them with
+custom writing functions.  See the discussion under Customizing libpng.
+
+    FILE *fp = fopen(file_name, "wb");
+    if (!fp)
+    {
+       return (ERROR);
+    }
+
+Next, png_struct and png_info need to be allocated and initialized.
+As these can be both relatively large, you may not want to store these
+on the stack, unless you have stack space to spare.  Of course, you
+will want to check if they return NULL.  If you are also reading,
+you won't want to name your read structure and your write structure
+both "png_ptr"; you can call them anything you like, such as
+"read_ptr" and "write_ptr".  Look at pngtest.c, for example.
+
+    png_structp png_ptr = png_create_write_struct
+       (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+        user_error_fn, user_warning_fn);
+    if (!png_ptr)
+       return (ERROR);
+
+    png_infop info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr)
+    {
+       png_destroy_write_struct(&png_ptr,
+         (png_infopp)NULL);
+       return (ERROR);
+    }
+
+If you want to use your own memory allocation routines,
+define PNG_USER_MEM_SUPPORTED and use
+png_create_write_struct_2() instead of png_create_write_struct():
+
+    png_structp png_ptr = png_create_write_struct_2
+       (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+        user_error_fn, user_warning_fn, (png_voidp)
+        user_mem_ptr, user_malloc_fn, user_free_fn);
+
+After you have these structures, you will need to set up the
+error handling.  When libpng encounters an error, it expects to
+longjmp() back to your routine.  Therefore, you will need to call
+setjmp() and pass the png_jmpbuf(png_ptr).  If you
+write the file from different routines, you will need to update
+the png_jmpbuf(png_ptr) every time you enter a new routine that will
+call a png_*() function.  See your documentation of setjmp/longjmp
+for your compiler for more information on setjmp/longjmp.  See
+the discussion on libpng error handling in the Customizing Libpng
+section below for more information on the libpng error handling.
+
+    if (setjmp(png_jmpbuf(png_ptr)))
+    {
+       png_destroy_write_struct(&png_ptr, &info_ptr);
+       fclose(fp);
+       return (ERROR);
+    }
+    ...
+    return;
+
+If you would rather avoid the complexity of setjmp/longjmp issues,
+you can compile libpng with PNG_SETJMP_NOT_SUPPORTED, in which case
+errors will result in a call to PNG_ABORT() which defaults to abort().
+
+Now you need to set up the output code.  The default for libpng is to
+use the C function fwrite().  If you use this, you will need to pass a
+valid FILE * in the function png_init_io().  Be sure that the file is
+opened in binary mode.  Again, if you wish to handle writing data in
+another way, see the discussion on libpng I/O handling in the Customizing
+Libpng section below.
+
+    png_init_io(png_ptr, fp);
+
+Write callbacks
+
+At this point, you can set up a callback function that will be
+called after each row has been written, which you can use to control
+a progress meter or the like.  It's demonstrated in pngtest.c.
+You must supply a function
+
+    void write_row_callback(png_ptr, png_uint_32 row,
+       int pass);
+    {
+      /* put your code here */
+    }
+
+(You can give it another name that you like instead of "write_row_callback")
+
+To inform libpng about your function, use
+
+    png_set_write_status_fn(png_ptr, write_row_callback);
+
+You now have the option of modifying how the compression library will
+run.  The following functions are mainly for testing, but may be useful
+in some cases, like if you need to write PNG files extremely fast and
+are willing to give up some compression, or if you want to get the
+maximum possible compression at the expense of slower writing.  If you
+have no special needs in this area, let the library do what it wants by
+not calling this function at all, as it has been tuned to deliver a good
+speed/compression ratio. The second parameter to png_set_filter() is
+the filter method, for which the only valid values are 0 (as of the
+July 1999 PNG specification, version 1.2) or 64 (if you are writing
+a PNG datastream that is to be embedded in a MNG datastream).  The third
+parameter is a flag that indicates which filter type(s) are to be tested
+for each scanline.  See the PNG specification for details on the specific filter
+types.
+
+
+    /* turn on or off filtering, and/or choose
+       specific filters.  You can use either a single
+       PNG_FILTER_VALUE_NAME or the logical OR of one
+       or more PNG_FILTER_NAME masks. */
+    png_set_filter(png_ptr, 0,
+       PNG_FILTER_NONE  | PNG_FILTER_VALUE_NONE |
+       PNG_FILTER_SUB   | PNG_FILTER_VALUE_SUB  |
+       PNG_FILTER_UP    | PNG_FILTER_VALUE_UP   |
+       PNG_FILTER_AVE   | PNG_FILTER_VALUE_AVE  |
+       PNG_FILTER_PAETH | PNG_FILTER_VALUE_PAETH|
+       PNG_ALL_FILTERS);
+
+If an application
+wants to start and stop using particular filters during compression,
+it should start out with all of the filters (to ensure that the previous
+row of pixels will be stored in case it's needed later), and then add
+and remove them after the start of compression.
+
+If you are writing a PNG datastream that is to be embedded in a MNG
+datastream, the second parameter can be either 0 or 64.
+
+The png_set_compression_*() functions interface to the zlib compression
+library, and should mostly be ignored unless you really know what you are
+doing.  The only generally useful call is png_set_compression_level()
+which changes how much time zlib spends on trying to compress the image
+data.  See the Compression Library (zlib.h and algorithm.txt, distributed
+with zlib) for details on the compression levels.
+
+    /* set the zlib compression level */
+    png_set_compression_level(png_ptr,
+        Z_BEST_COMPRESSION);
+
+    /* set other zlib parameters */
+    png_set_compression_mem_level(png_ptr, 8);
+    png_set_compression_strategy(png_ptr,
+        Z_DEFAULT_STRATEGY);
+    png_set_compression_window_bits(png_ptr, 15);
+    png_set_compression_method(png_ptr, 8);
+    png_set_compression_buffer_size(png_ptr, 8192)
+
+extern PNG_EXPORT(void,png_set_zbuf_size)
+
+Setting the contents of info for output
+
+You now need to fill in the png_info structure with all the data you
+wish to write before the actual image.  Note that the only thing you
+are allowed to write after the image is the text chunks and the time
+chunk (as of PNG Specification 1.2, anyway).  See png_write_end() and
+the latest PNG specification for more information on that.  If you
+wish to write them before the image, fill them in now, and flag that
+data as being valid.  If you want to wait until after the data, don't
+fill them until png_write_end().  For all the fields in png_info and
+their data types, see png.h.  For explanations of what the fields
+contain, see the PNG specification.
+
+Some of the more important parts of the png_info are:
+
+    png_set_IHDR(png_ptr, info_ptr, width, height,
+       bit_depth, color_type, interlace_type,
+       compression_type, filter_method)
+    width          - holds the width of the image
+                     in pixels (up to 2^31).
+    height         - holds the height of the image
+                     in pixels (up to 2^31).
+    bit_depth      - holds the bit depth of one of the
+                     image channels.
+                     (valid values are 1, 2, 4, 8, 16
+                     and depend also on the
+                     color_type.  See also significant
+                     bits (sBIT) below).
+    color_type     - describes which color/alpha
+                     channels are present.
+                     PNG_COLOR_TYPE_GRAY
+                        (bit depths 1, 2, 4, 8, 16)
+                     PNG_COLOR_TYPE_GRAY_ALPHA
+                        (bit depths 8, 16)
+                     PNG_COLOR_TYPE_PALETTE
+                        (bit depths 1, 2, 4, 8)
+                     PNG_COLOR_TYPE_RGB
+                        (bit_depths 8, 16)
+                     PNG_COLOR_TYPE_RGB_ALPHA
+                        (bit_depths 8, 16)
+
+                     PNG_COLOR_MASK_PALETTE
+                     PNG_COLOR_MASK_COLOR
+                     PNG_COLOR_MASK_ALPHA
+
+    interlace_type - PNG_INTERLACE_NONE or
+                     PNG_INTERLACE_ADAM7
+    compression_type - (must be
+                     PNG_COMPRESSION_TYPE_DEFAULT)
+    filter_method  - (must be PNG_FILTER_TYPE_DEFAULT
+                     or, if you are writing a PNG to
+                     be embedded in a MNG datastream,
+                     can also be
+                     PNG_INTRAPIXEL_DIFFERENCING)
+
+    png_set_PLTE(png_ptr, info_ptr, palette,
+       num_palette);
+    palette        - the palette for the file
+                     (array of png_color)
+    num_palette    - number of entries in the palette
+
+    png_set_gAMA(png_ptr, info_ptr, gamma);
+    gamma          - the gamma the image was created
+                     at (PNG_INFO_gAMA)
+
+    png_set_sRGB(png_ptr, info_ptr, srgb_intent);
+    srgb_intent    - the rendering intent
+                     (PNG_INFO_sRGB) The presence of
+                     the sRGB chunk means that the pixel
+                     data is in the sRGB color space.
+                     This chunk also implies specific
+                     values of gAMA and cHRM.  Rendering
+                     intent is the CSS-1 property that
+                     has been defined by the International
+                     Color Consortium
+                     (http://www.color.org).
+                     It can be one of
+                     PNG_sRGB_INTENT_SATURATION,
+                     PNG_sRGB_INTENT_PERCEPTUAL,
+                     PNG_sRGB_INTENT_ABSOLUTE, or
+                     PNG_sRGB_INTENT_RELATIVE.
+
+
+    png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr,
+       srgb_intent);
+    srgb_intent    - the rendering intent
+                     (PNG_INFO_sRGB) The presence of the
+                     sRGB chunk means that the pixel
+                     data is in the sRGB color space.
+                     This function also causes gAMA and
+                     cHRM chunks with the specific values
+                     that are consistent with sRGB to be
+                     written.
+
+    png_set_iCCP(png_ptr, info_ptr, name, compression_type,
+                      profile, proflen);
+    name            - The profile name.
+    compression     - The compression type; always
+                      PNG_COMPRESSION_TYPE_BASE for PNG 1.0.
+                      You may give NULL to this argument to
+                      ignore it.
+    profile         - International Color Consortium color
+                      profile data. May contain NULs.
+    proflen         - length of profile data in bytes.
+
+    png_set_sBIT(png_ptr, info_ptr, sig_bit);
+    sig_bit        - the number of significant bits for
+                     (PNG_INFO_sBIT) each of the gray, red,
+                     green, and blue channels, whichever are
+                     appropriate for the given color type
+                     (png_color_16)
+
+    png_set_tRNS(png_ptr, info_ptr, trans, num_trans,
+       trans_values);
+    trans          - array of transparent entries for
+                     palette (PNG_INFO_tRNS)
+    trans_values   - graylevel or color sample values of
+                     the single transparent color for
+                     non-paletted images (PNG_INFO_tRNS)
+    num_trans      - number of transparent entries
+                     (PNG_INFO_tRNS)
+
+    png_set_hIST(png_ptr, info_ptr, hist);
+                    (PNG_INFO_hIST)
+    hist           - histogram of palette (array of
+                     png_uint_16)
+
+    png_set_tIME(png_ptr, info_ptr, mod_time);
+    mod_time       - time image was last modified
+                     (PNG_VALID_tIME)
+
+    png_set_bKGD(png_ptr, info_ptr, background);
+    background     - background color (PNG_VALID_bKGD)
+
+    png_set_text(png_ptr, info_ptr, text_ptr, num_text);
+    text_ptr       - array of png_text holding image
+                     comments
+    text_ptr[i].compression - type of compression used
+                 on "text" PNG_TEXT_COMPRESSION_NONE
+                           PNG_TEXT_COMPRESSION_zTXt
+                           PNG_ITXT_COMPRESSION_NONE
+                           PNG_ITXT_COMPRESSION_zTXt
+    text_ptr[i].key   - keyword for comment.  Must contain
+                 1-79 characters.
+    text_ptr[i].text  - text comments for current
+                         keyword.  Can be NULL or empty.
+    text_ptr[i].text_length - length of text string,
+                 after decompression, 0 for iTXt
+    text_ptr[i].itxt_length - length of itxt string,
+                 after decompression, 0 for tEXt/zTXt
+    text_ptr[i].lang  - language of comment (NULL or
+                         empty for unknown).
+    text_ptr[i].translated_keyword  - keyword in UTF-8 (NULL
+                         or empty for unknown).
+    num_text       - number of comments
+
+    png_set_sPLT(png_ptr, info_ptr, &palette_ptr,
+       num_spalettes);
+    palette_ptr    - array of png_sPLT_struct structures
+                     to be added to the list of palettes
+                     in the info structure.
+    num_spalettes  - number of palette structures to be
+                     added.
+
+    png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y,
+        unit_type);
+    offset_x  - positive offset from the left
+                     edge of the screen
+    offset_y  - positive offset from the top
+                     edge of the screen
+    unit_type - PNG_OFFSET_PIXEL, PNG_OFFSET_MICROMETER
+
+    png_set_pHYs(png_ptr, info_ptr, res_x, res_y,
+        unit_type);
+    res_x       - pixels/unit physical resolution
+                  in x direction
+    res_y       - pixels/unit physical resolution
+                  in y direction
+    unit_type   - PNG_RESOLUTION_UNKNOWN,
+                  PNG_RESOLUTION_METER
+
+    png_set_sCAL(png_ptr, info_ptr, unit, width, height)
+    unit        - physical scale units (an integer)
+    width       - width of a pixel in physical scale units
+    height      - height of a pixel in physical scale units
+                  (width and height are doubles)
+
+    png_set_sCAL_s(png_ptr, info_ptr, unit, width, height)
+    unit        - physical scale units (an integer)
+    width       - width of a pixel in physical scale units
+    height      - height of a pixel in physical scale units
+                 (width and height are strings like "2.54")
+
+    png_set_unknown_chunks(png_ptr, info_ptr, &unknowns,
+       num_unknowns)
+    unknowns          - array of png_unknown_chunk
+                        structures holding unknown chunks
+    unknowns[i].name  - name of unknown chunk
+    unknowns[i].data  - data of unknown chunk
+    unknowns[i].size  - size of unknown chunk's data
+    unknowns[i].location - position to write chunk in file
+                           0: do not write chunk
+                           PNG_HAVE_IHDR: before PLTE
+                           PNG_HAVE_PLTE: before IDAT
+                           PNG_AFTER_IDAT: after IDAT
+
+The "location" member is set automatically according to
+what part of the output file has already been written.
+You can change its value after calling png_set_unknown_chunks()
+as demonstrated in pngtest.c.  Within each of the "locations",
+the chunks are sequenced according to their position in the
+structure (that is, the value of "i", which is the order in which
+the chunk was either read from the input file or defined with
+png_set_unknown_chunks).
+
+A quick word about text and num_text.  text is an array of png_text
+structures.  num_text is the number of valid structures in the array.
+Each png_text structure holds a language code, a keyword, a text value,
+and a compression type.
+
+The compression types have the same valid numbers as the compression
+types of the image data.  Currently, the only valid number is zero.
+However, you can store text either compressed or uncompressed, unlike
+images, which always have to be compressed.  So if you don't want the
+text compressed, set the compression type to PNG_TEXT_COMPRESSION_NONE.
+Because tEXt and zTXt chunks don't have a language field, if you
+specify PNG_TEXT_COMPRESSION_NONE or PNG_TEXT_COMPRESSION_zTXt
+any language code or translated keyword will not be written out.
+
+Until text gets around 1000 bytes, it is not worth compressing it.
+After the text has been written out to the file, the compression type
+is set to PNG_TEXT_COMPRESSION_NONE_WR or PNG_TEXT_COMPRESSION_zTXt_WR,
+so that it isn't written out again at the end (in case you are calling
+png_write_end() with the same struct.
+
+The keywords that are given in the PNG Specification are:
+
+    Title            Short (one line) title or
+                     caption for image
+    Author           Name of image's creator
+    Description      Description of image (possibly long)
+    Copyright        Copyright notice
+    Creation Time    Time of original image creation
+                     (usually RFC 1123 format, see below)
+    Software         Software used to create the image
+    Disclaimer       Legal disclaimer
+    Warning          Warning of nature of content
+    Source           Device used to create the image
+    Comment          Miscellaneous comment; conversion
+                     from other image format
+
+The keyword-text pairs work like this.  Keywords should be short
+simple descriptions of what the comment is about.  Some typical
+keywords are found in the PNG specification, as is some recommendations
+on keywords.  You can repeat keywords in a file.  You can even write
+some text before the image and some after.  For example, you may want
+to put a description of the image before the image, but leave the
+disclaimer until after, so viewers working over modem connections
+don't have to wait for the disclaimer to go over the modem before
+they start seeing the image.  Finally, keywords should be full
+words, not abbreviations.  Keywords and text are in the ISO 8859-1
+(Latin-1) character set (a superset of regular ASCII) and can not
+contain NUL characters, and should not contain control or other
+unprintable characters.  To make the comments widely readable, stick
+with basic ASCII, and avoid machine specific character set extensions
+like the IBM-PC character set.  The keyword must be present, but
+you can leave off the text string on non-compressed pairs.
+Compressed pairs must have a text string, as only the text string
+is compressed anyway, so the compression would be meaningless.
+
+PNG supports modification time via the png_time structure.  Two
+conversion routines are provided, png_convert_from_time_t() for
+time_t and png_convert_from_struct_tm() for struct tm.  The
+time_t routine uses gmtime().  You don't have to use either of
+these, but if you wish to fill in the png_time structure directly,
+you should provide the time in universal time (GMT) if possible
+instead of your local time.  Note that the year number is the full
+year (e.g. 1998, rather than 98 - PNG is year 2000 compliant!), and
+that months start with 1.
+
+If you want to store the time of the original image creation, you should
+use a plain tEXt chunk with the "Creation Time" keyword.  This is
+necessary because the "creation time" of a PNG image is somewhat vague,
+depending on whether you mean the PNG file, the time the image was
+created in a non-PNG format, a still photo from which the image was
+scanned, or possibly the subject matter itself.  In order to facilitate
+machine-readable dates, it is recommended that the "Creation Time"
+tEXt chunk use RFC 1123 format dates (e.g. "22 May 1997 18:07:10 GMT"),
+although this isn't a requirement.  Unlike the tIME chunk, the
+"Creation Time" tEXt chunk is not expected to be automatically changed
+by the software.  To facilitate the use of RFC 1123 dates, a function
+png_convert_to_rfc1123(png_timep) is provided to convert from PNG
+time to an RFC 1123 format string.
+
+Writing unknown chunks
+
+You can use the png_set_unknown_chunks function to queue up chunks
+for writing.  You give it a chunk name, raw data, and a size; that's
+all there is to it.  The chunks will be written by the next following
+png_write_info_before_PLTE, png_write_info, or png_write_end function.
+Any chunks previously read into the info structure's unknown-chunk
+list will also be written out in a sequence that satisfies the PNG
+specification's ordering rules.
+
+The high-level write interface
+
+At this point there are two ways to proceed; through the high-level
+write interface, or through a sequence of low-level write operations.
+You can use the high-level interface if your image data is present
+in the info structure.  All defined output
+transformations are permitted, enabled by the following masks.
+
+    PNG_TRANSFORM_IDENTITY      No transformation
+    PNG_TRANSFORM_PACKING       Pack 1, 2 and 4-bit samples
+    PNG_TRANSFORM_PACKSWAP      Change order of packed
+                                pixels to LSB first
+    PNG_TRANSFORM_INVERT_MONO   Invert monochrome images
+    PNG_TRANSFORM_SHIFT         Normalize pixels to the
+                                sBIT depth
+    PNG_TRANSFORM_BGR           Flip RGB to BGR, RGBA
+                                to BGRA
+    PNG_TRANSFORM_SWAP_ALPHA    Flip RGBA to ARGB or GA
+                                to AG
+    PNG_TRANSFORM_INVERT_ALPHA  Change alpha from opacity
+                                to transparency
+    PNG_TRANSFORM_SWAP_ENDIAN   Byte-swap 16-bit samples
+    PNG_TRANSFORM_STRIP_FILLER  Strip out filler bytes.
+
+If you have valid image data in the info structure (you can use
+png_set_rows() to put image data in the info structure), simply do this:
+
+    png_write_png(png_ptr, info_ptr, png_transforms, NULL)
+
+where png_transforms is an integer containing the logical OR of some set of
+transformation flags.  This call is equivalent to png_write_info(),
+followed the set of transformations indicated by the transform mask,
+then png_write_image(), and finally png_write_end().
+
+(The final parameter of this call is not yet used.  Someday it might point
+to transformation parameters required by some future output transform.)
+
+You must use png_transforms and not call any png_set_transform() functions
+when you use png_write_png().
+
+The low-level write interface
+
+If you are going the low-level route instead, you are now ready to
+write all the file information up to the actual image data.  You do
+this with a call to png_write_info().
+
+    png_write_info(png_ptr, info_ptr);
+
+Note that there is one transformation you may need to do before
+png_write_info().  In PNG files, the alpha channel in an image is the
+level of opacity.  If your data is supplied as a level of
+transparency, you can invert the alpha channel before you write it, so
+that 0 is fully transparent and 255 (in 8-bit or paletted images) or
+65535 (in 16-bit images) is fully opaque, with
+
+    png_set_invert_alpha(png_ptr);
+
+This must appear before png_write_info() instead of later with the
+other transformations because in the case of paletted images the tRNS
+chunk data has to be inverted before the tRNS chunk is written.  If
+your image is not a paletted image, the tRNS data (which in such cases
+represents a single color to be rendered as transparent) won't need to
+be changed, and you can safely do this transformation after your
+png_write_info() call.
+
+If you need to write a private chunk that you want to appear before
+the PLTE chunk when PLTE is present, you can write the PNG info in
+two steps, and insert code to write your own chunk between them:
+
+    png_write_info_before_PLTE(png_ptr, info_ptr);
+    png_set_unknown_chunks(png_ptr, info_ptr, ...);
+    png_write_info(png_ptr, info_ptr);
+
+After you've written the file information, you can set up the library
+to handle any special transformations of the image data.  The various
+ways to transform the data will be described in the order that they
+should occur.  This is important, as some of these change the color
+type and/or bit depth of the data, and some others only work on
+certain color types and bit depths.  Even though each transformation
+checks to see if it has data that it can do something with, you should
+make sure to only enable a transformation if it will be valid for the
+data.  For example, don't swap red and blue on grayscale data.
+
+PNG files store RGB pixels packed into 3 or 6 bytes.  This code tells
+the library to strip input data that has 4 or 8 bytes per pixel down
+to 3 or 6 bytes (or strip 2 or 4-byte grayscale+filler data to 1 or 2
+bytes per pixel).
+
+    png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
+
+where the 0 is unused, and the location is either PNG_FILLER_BEFORE or
+PNG_FILLER_AFTER, depending upon whether the filler byte in the pixel
+is stored XRGB or RGBX.
+
+PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as
+they can, resulting in, for example, 8 pixels per byte for 1 bit files.
+If the data is supplied at 1 pixel per byte, use this code, which will
+correctly pack the pixels into a single byte:
+
+    png_set_packing(png_ptr);
+
+PNG files reduce possible bit depths to 1, 2, 4, 8, and 16.  If your
+data is of another bit depth, you can write an sBIT chunk into the
+file so that decoders can recover the original data if desired.
+
+    /* Set the true bit depth of the image data */
+    if (color_type & PNG_COLOR_MASK_COLOR)
+    {
+        sig_bit.red = true_bit_depth;
+        sig_bit.green = true_bit_depth;
+        sig_bit.blue = true_bit_depth;
+    }
+    else
+    {
+        sig_bit.gray = true_bit_depth;
+    }
+    if (color_type & PNG_COLOR_MASK_ALPHA)
+    {
+        sig_bit.alpha = true_bit_depth;
+    }
+
+    png_set_sBIT(png_ptr, info_ptr, &sig_bit);
+
+If the data is stored in the row buffer in a bit depth other than
+one supported by PNG (e.g. 3 bit data in the range 0-7 for a 4-bit PNG),
+this will scale the values to appear to be the correct bit depth as
+is required by PNG.
+
+    png_set_shift(png_ptr, &sig_bit);
+
+PNG files store 16 bit pixels in network byte order (big-endian,
+ie. most significant bits first).  This code would be used if they are
+supplied the other way (little-endian, i.e. least significant bits
+first, the way PCs store them):
+
+    if (bit_depth > 8)
+       png_set_swap(png_ptr);
+
+If you are using packed-pixel images (1, 2, or 4 bits/pixel), and you
+need to change the order the pixels are packed into bytes, you can use:
+
+    if (bit_depth < 8)
+       png_set_packswap(png_ptr);
+
+PNG files store 3 color pixels in red, green, blue order.  This code
+would be used if they are supplied as blue, green, red:
+
+    png_set_bgr(png_ptr);
+
+PNG files describe monochrome as black being zero and white being
+one. This code would be used if the pixels are supplied with this reversed
+(black being one and white being zero):
+
+    png_set_invert_mono(png_ptr);
+
+Finally, you can write your own transformation function if none of
+the existing ones meets your needs.  This is done by setting a callback
+with
+
+    png_set_write_user_transform_fn(png_ptr,
+       write_transform_fn);
+
+You must supply the function
+
+    void write_transform_fn(png_ptr ptr, row_info_ptr
+       row_info, png_bytep data)
+
+See pngtest.c for a working example.  Your function will be called
+before any of the other transformations are processed.
+
+You can also set up a pointer to a user structure for use by your
+callback function.
+
+    png_set_user_transform_info(png_ptr, user_ptr, 0, 0);
+
+The user_channels and user_depth parameters of this function are ignored
+when writing; you can set them to zero as shown.
+
+You can retrieve the pointer via the function png_get_user_transform_ptr().
+For example:
+
+    voidp write_user_transform_ptr =
+       png_get_user_transform_ptr(png_ptr);
+
+It is possible to have libpng flush any pending output, either manually,
+or automatically after a certain number of lines have been written.  To
+flush the output stream a single time call:
+
+    png_write_flush(png_ptr);
+
+and to have libpng flush the output stream periodically after a certain
+number of scanlines have been written, call:
+
+    png_set_flush(png_ptr, nrows);
+
+Note that the distance between rows is from the last time png_write_flush()
+was called, or the first row of the image if it has never been called.
+So if you write 50 lines, and then png_set_flush 25, it will flush the
+output on the next scanline, and every 25 lines thereafter, unless
+png_write_flush() is called before 25 more lines have been written.
+If nrows is too small (less than about 10 lines for a 640 pixel wide
+RGB image) the image compression may decrease noticeably (although this
+may be acceptable for real-time applications).  Infrequent flushing will
+only degrade the compression performance by a few percent over images
+that do not use flushing.
+
+Writing the image data
+
+That's it for the transformations.  Now you can write the image data.
+The simplest way to do this is in one function call.  If you have the
+whole image in memory, you can just call png_write_image() and libpng
+will write the image.  You will need to pass in an array of pointers to
+each row.  This function automatically handles interlacing, so you don't
+need to call png_set_interlace_handling() or call this function multiple
+times, or any of that other stuff necessary with png_write_rows().
+
+    png_write_image(png_ptr, row_pointers);
+
+where row_pointers is:
+
+    png_byte *row_pointers[height];
+
+You can point to void or char or whatever you use for pixels.
+
+If you don't want to write the whole image at once, you can
+use png_write_rows() instead.  If the file is not interlaced,
+this is simple:
+
+    png_write_rows(png_ptr, row_pointers,
+       number_of_rows);
+
+row_pointers is the same as in the png_write_image() call.
+
+If you are just writing one row at a time, you can do this with
+a single row_pointer instead of an array of row_pointers:
+
+    png_bytep row_pointer = row;
+
+    png_write_row(png_ptr, row_pointer);
+
+When the file is interlaced, things can get a good deal more
+complicated.  The only currently (as of the PNG Specification
+version 1.2, dated July 1999) defined interlacing scheme for PNG files
+is the "Adam7" interlace scheme, that breaks down an
+image into seven smaller images of varying size.  libpng will build
+these images for you, or you can do them yourself.  If you want to
+build them yourself, see the PNG specification for details of which
+pixels to write when.
+
+If you don't want libpng to handle the interlacing details, just
+use png_set_interlace_handling() and call png_write_rows() the
+correct number of times to write all seven sub-images.
+
+If you want libpng to build the sub-images, call this before you start
+writing any rows:
+
+    number_of_passes =
+       png_set_interlace_handling(png_ptr);
+
+This will return the number of passes needed.  Currently, this
+is seven, but may change if another interlace type is added.
+
+Then write the complete image number_of_passes times.
+
+    png_write_rows(png_ptr, row_pointers,
+       number_of_rows);
+
+As some of these rows are not used, and thus return immediately,
+you may want to read about interlacing in the PNG specification,
+and only update the rows that are actually used.
+
+Finishing a sequential write
+
+After you are finished writing the image, you should finish writing
+the file.  If you are interested in writing comments or time, you should
+pass an appropriately filled png_info pointer.  If you are not interested,
+you can pass NULL.
+
+    png_write_end(png_ptr, info_ptr);
+
+When you are done, you can free all memory used by libpng like this:
+
+    png_destroy_write_struct(&png_ptr, &info_ptr);
+
+It is also possible to individually free the info_ptr members that
+point to libpng-allocated storage with the following function:
+
+    png_free_data(png_ptr, info_ptr, mask, seq)
+    mask  - identifies data to be freed, a mask
+            containing the logical OR of one or
+            more of
+              PNG_FREE_PLTE, PNG_FREE_TRNS,
+              PNG_FREE_HIST, PNG_FREE_ICCP,
+              PNG_FREE_PCAL, PNG_FREE_ROWS,
+              PNG_FREE_SCAL, PNG_FREE_SPLT,
+              PNG_FREE_TEXT, PNG_FREE_UNKN,
+            or simply PNG_FREE_ALL
+    seq   - sequence number of item to be freed
+            (-1 for all items)
+
+This function may be safely called when the relevant storage has
+already been freed, or has not yet been allocated, or was allocated
+by the user  and not by libpng,  and will in those
+cases do nothing.  The "seq" parameter is ignored if only one item
+of the selected data type, such as PLTE, is allowed.  If "seq" is not
+-1, and multiple items are allowed for the data type identified in
+the mask, such as text or sPLT, only the n'th item in the structure
+is freed, where n is "seq".
+
+If you allocated data such as a palette that you passed
+in to libpng with png_set_*, you must not free it until just before the call to
+png_destroy_write_struct().
+
+The default behavior is only to free data that was allocated internally
+by libpng.  This can be changed, so that libpng will not free the data,
+or so that it will free data that was allocated by the user with png_malloc()
+or png_zalloc() and passed in via a png_set_*() function, with
+
+    png_data_freer(png_ptr, info_ptr, freer, mask)
+    mask   - which data elements are affected
+             same choices as in png_free_data()
+    freer  - one of
+               PNG_DESTROY_WILL_FREE_DATA
+               PNG_SET_WILL_FREE_DATA
+               PNG_USER_WILL_FREE_DATA
+
+For example, to transfer responsibility for some data from a read structure
+to a write structure, you could use
+
+    png_data_freer(read_ptr, read_info_ptr,
+       PNG_USER_WILL_FREE_DATA,
+       PNG_FREE_PLTE|PNG_FREE_tRNS|PNG_FREE_hIST)
+    png_data_freer(write_ptr, write_info_ptr,
+       PNG_DESTROY_WILL_FREE_DATA,
+       PNG_FREE_PLTE|PNG_FREE_tRNS|PNG_FREE_hIST)
+
+thereby briefly reassigning responsibility for freeing to the user but
+immediately afterwards reassigning it once more to the write_destroy
+function.  Having done this, it would then be safe to destroy the read
+structure and continue to use the PLTE, tRNS, and hIST data in the write
+structure.
+
+This function only affects data that has already been allocated.
+You can call this function before calling after the png_set_*() functions
+to control whether the user or png_destroy_*() is supposed to free the data.
+When the user assumes responsibility for libpng-allocated data, the
+application must use
+png_free() to free it, and when the user transfers responsibility to libpng
+for data that the user has allocated, the user must have used png_malloc()
+or png_zalloc() to allocate it.
+
+If you allocated text_ptr.text, text_ptr.lang, and text_ptr.translated_keyword
+separately, do not transfer responsibility for freeing text_ptr to libpng,
+because when libpng fills a png_text structure it combines these members with
+the key member, and png_free_data() will free only text_ptr.key.  Similarly,
+if you transfer responsibility for free'ing text_ptr from libpng to your
+application, your application must not separately free those members.
+For a more compact example of writing a PNG image, see the file example.c.
+
+V. Modifying/Customizing libpng:
+
+There are three issues here.  The first is changing how libpng does
+standard things like memory allocation, input/output, and error handling.
+The second deals with more complicated things like adding new chunks,
+adding new transformations, and generally changing how libpng works.
+Both of those are compile-time issues; that is, they are generally
+determined at the time the code is written, and there is rarely a need
+to provide the user with a means of changing them.  The third is a
+run-time issue:  choosing between and/or tuning one or more alternate
+versions of computationally intensive routines; specifically, optimized
+assembly-language (and therefore compiler- and platform-dependent)
+versions.
+
+Memory allocation, input/output, and error handling
+
+All of the memory allocation, input/output, and error handling in libpng
+goes through callbacks that are user-settable.  The default routines are
+in pngmem.c, pngrio.c, pngwio.c, and pngerror.c, respectively.  To change
+these functions, call the appropriate png_set_*_fn() function.
+
+Memory allocation is done through the functions png_malloc()
+and png_free().  These currently just call the standard C functions.  If
+your pointers can't access more then 64K at a time, you will want to set
+MAXSEG_64K in zlib.h.  Since it is unlikely that the method of handling
+memory allocation on a platform will change between applications, these
+functions must be modified in the library at compile time.  If you prefer
+to use a different method of allocating and freeing data, you can use
+png_create_read_struct_2() or png_create_write_struct_2() to register
+your own functions as described above.
+These functions also provide a void pointer that can be retrieved via
+
+    mem_ptr=png_get_mem_ptr(png_ptr);
+
+Your replacement memory functions must have prototypes as follows:
+
+    png_voidp malloc_fn(png_structp png_ptr,
+       png_size_t size);
+    void free_fn(png_structp png_ptr, png_voidp ptr);
+
+Your malloc_fn() must return NULL in case of failure.  The png_malloc()
+function will normally call png_error() if it receives a NULL from the
+system memory allocator or from your replacement malloc_fn().
+
+Input/Output in libpng is done through png_read() and png_write(),
+which currently just call fread() and fwrite().  The FILE * is stored in
+png_struct and is initialized via png_init_io().  If you wish to change
+the method of I/O, the library supplies callbacks that you can set
+through the function png_set_read_fn() and png_set_write_fn() at run
+time, instead of calling the png_init_io() function.  These functions
+also provide a void pointer that can be retrieved via the function
+png_get_io_ptr().  For example:
+
+    png_set_read_fn(png_structp read_ptr,
+        voidp read_io_ptr, png_rw_ptr read_data_fn)
+
+    png_set_write_fn(png_structp write_ptr,
+        voidp write_io_ptr, png_rw_ptr write_data_fn,
+        png_flush_ptr output_flush_fn);
+
+    voidp read_io_ptr = png_get_io_ptr(read_ptr);
+    voidp write_io_ptr = png_get_io_ptr(write_ptr);
+
+The replacement I/O functions must have prototypes as follows:
+
+    void user_read_data(png_structp png_ptr,
+        png_bytep data, png_size_t length);
+    void user_write_data(png_structp png_ptr,
+        png_bytep data, png_size_t length);
+    void user_flush_data(png_structp png_ptr);
+
+Supplying NULL for the read, write, or flush functions sets them back
+to using the default C stream functions.  It is an error to read from
+a write stream, and vice versa.
+
+Error handling in libpng is done through png_error() and png_warning().
+Errors handled through png_error() are fatal, meaning that png_error()
+should never return to its caller.  Currently, this is handled via
+setjmp() and longjmp() (unless you have compiled libpng with
+PNG_SETJMP_NOT_SUPPORTED, in which case it is handled via PNG_ABORT()),
+but you could change this to do things like exit() if you should wish.
+
+On non-fatal errors, png_warning() is called
+to print a warning message, and then control returns to the calling code.
+By default png_error() and png_warning() print a message on stderr via
+fprintf() unless the library is compiled with PNG_NO_CONSOLE_IO defined
+(because you don't want the messages) or PNG_NO_STDIO defined (because
+fprintf() isn't available).  If you wish to change the behavior of the error
+functions, you will need to set up your own message callbacks.  These
+functions are normally supplied at the time that the png_struct is created.
+It is also possible to redirect errors and warnings to your own replacement
+functions after png_create_*_struct() has been called by calling:
+
+    png_set_error_fn(png_structp png_ptr,
+        png_voidp error_ptr, png_error_ptr error_fn,
+        png_error_ptr warning_fn);
+
+    png_voidp error_ptr = png_get_error_ptr(png_ptr);
+
+If NULL is supplied for either error_fn or warning_fn, then the libpng
+default function will be used, calling fprintf() and/or longjmp() if a
+problem is encountered.  The replacement error functions should have
+parameters as follows:
+
+    void user_error_fn(png_structp png_ptr,
+        png_const_charp error_msg);
+    void user_warning_fn(png_structp png_ptr,
+        png_const_charp warning_msg);
+
+The motivation behind using setjmp() and longjmp() is the C++ throw and
+catch exception handling methods.  This makes the code much easier to write,
+as there is no need to check every return code of every function call.
+However, there are some uncertainties about the status of local variables
+after a longjmp, so the user may want to be careful about doing anything after
+setjmp returns non-zero besides returning itself.  Consult your compiler
+documentation for more details.  For an alternative approach, you may wish
+to use the "cexcept" facility (see http://cexcept.sourceforge.net).
+
+Custom chunks
+
+If you need to read or write custom chunks, you may need to get deeper
+into the libpng code.  The library now has mechanisms for storing
+and writing chunks of unknown type; you can even declare callbacks
+for custom chunks.  Hoewver, this may not be good enough if the
+library code itself needs to know about interactions between your
+chunk and existing `intrinsic' chunks.
+
+If you need to write a new intrinsic chunk, first read the PNG
+specification. Acquire a first level of
+understanding of how it works.  Pay particular attention to the
+sections that describe chunk names, and look at how other chunks were
+designed, so you can do things similarly.  Second, check out the
+sections of libpng that read and write chunks.  Try to find a chunk
+that is similar to yours and use it as a template.  More details can
+be found in the comments inside the code.  It is best to handle unknown
+chunks in a generic method, via callback functions, instead of by
+modifying libpng functions.
+
+If you wish to write your own transformation for the data, look through
+the part of the code that does the transformations, and check out some of
+the simpler ones to get an idea of how they work.  Try to find a similar
+transformation to the one you want to add and copy off of it.  More details
+can be found in the comments inside the code itself.
+
+Configuring for 16 bit platforms
+
+You will want to look into zconf.h to tell zlib (and thus libpng) that
+it cannot allocate more then 64K at a time.  Even if you can, the memory
+won't be accessible.  So limit zlib and libpng to 64K by defining MAXSEG_64K.
+
+Configuring for DOS
+
+For DOS users who only have access to the lower 640K, you will
+have to limit zlib's memory usage via a png_set_compression_mem_level()
+call.  See zlib.h or zconf.h in the zlib library for more information.
+
+Configuring for Medium Model
+
+Libpng's support for medium model has been tested on most of the popular
+compilers.  Make sure MAXSEG_64K gets defined, USE_FAR_KEYWORD gets
+defined, and FAR gets defined to far in pngconf.h, and you should be
+all set.  Everything in the library (except for zlib's structure) is
+expecting far data.  You must use the typedefs with the p or pp on
+the end for pointers (or at least look at them and be careful).  Make
+note that the rows of data are defined as png_bytepp, which is an
+unsigned char far * far *.
+
+Configuring for gui/windowing platforms:
+
+You will need to write new error and warning functions that use the GUI
+interface, as described previously, and set them to be the error and
+warning functions at the time that png_create_*_struct() is called,
+in order to have them available during the structure initialization.
+They can be changed later via png_set_error_fn().  On some compilers,
+you may also have to change the memory allocators (png_malloc, etc.).
+
+Configuring for compiler xxx:
+
+All includes for libpng are in pngconf.h.  If you need to add/change/delete
+an include, this is the place to do it.  The includes that are not
+needed outside libpng are protected by the PNG_INTERNAL definition,
+which is only defined for those routines inside libpng itself.  The
+files in libpng proper only include png.h, which includes pngconf.h.
+
+Configuring zlib:
+
+There are special functions to configure the compression.  Perhaps the
+most useful one changes the compression level, which currently uses
+input compression values in the range 0 - 9.  The library normally
+uses the default compression level (Z_DEFAULT_COMPRESSION = 6).  Tests
+have shown that for a large majority of images, compression values in
+the range 3-6 compress nearly as well as higher levels, and do so much
+faster.  For online applications it may be desirable to have maximum speed
+(Z_BEST_SPEED = 1).  With versions of zlib after v0.99, you can also
+specify no compression (Z_NO_COMPRESSION = 0), but this would create
+files larger than just storing the raw bitmap.  You can specify the
+compression level by calling:
+
+    png_set_compression_level(png_ptr, level);
+
+Another useful one is to reduce the memory level used by the library.
+The memory level defaults to 8, but it can be lowered if you are
+short on memory (running DOS, for example, where you only have 640K).
+Note that the memory level does have an effect on compression; among
+other things, lower levels will result in sections of incompressible
+data being emitted in smaller stored blocks, with a correspondingly
+larger relative overhead of up to 15% in the worst case.
+
+    png_set_compression_mem_level(png_ptr, level);
+
+The other functions are for configuring zlib.  They are not recommended
+for normal use and may result in writing an invalid PNG file.  See
+zlib.h for more information on what these mean.
+
+    png_set_compression_strategy(png_ptr,
+        strategy);
+    png_set_compression_window_bits(png_ptr,
+        window_bits);
+    png_set_compression_method(png_ptr, method);
+    png_set_compression_buffer_size(png_ptr, size);
+
+Controlling row filtering
+
+If you want to control whether libpng uses filtering or not, which
+filters are used, and how it goes about picking row filters, you
+can call one of these functions.  The selection and configuration
+of row filters can have a significant impact on the size and
+encoding speed and a somewhat lesser impact on the decoding speed
+of an image.  Filtering is enabled by default for RGB and grayscale
+images (with and without alpha), but not for paletted images nor
+for any images with bit depths less than 8 bits/pixel.
+
+The 'method' parameter sets the main filtering method, which is
+currently only '0' in the PNG 1.2 specification.  The 'filters'
+parameter sets which filter(s), if any, should be used for each
+scanline.  Possible values are PNG_ALL_FILTERS and PNG_NO_FILTERS
+to turn filtering on and off, respectively.
+
+Individual filter types are PNG_FILTER_NONE, PNG_FILTER_SUB,
+PNG_FILTER_UP, PNG_FILTER_AVG, PNG_FILTER_PAETH, which can be bitwise
+ORed together with '|' to specify one or more filters to use.
+These filters are described in more detail in the PNG specification.
+If you intend to change the filter type during the course of writing
+the image, you should start with flags set for all of the filters
+you intend to use so that libpng can initialize its internal
+structures appropriately for all of the filter types.  (Note that this
+means the first row must always be adaptively filtered, because libpng
+currently does not allocate the filter buffers until png_write_row()
+is called for the first time.)
+
+    filters = PNG_FILTER_NONE | PNG_FILTER_SUB
+              PNG_FILTER_UP | PNG_FILTER_AVE |
+              PNG_FILTER_PAETH | PNG_ALL_FILTERS;
+
+    png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE,
+       filters);
+              The second parameter can also be
+              PNG_INTRAPIXEL_DIFFERENCING if you are
+              writing a PNG to be embedded in a MNG
+              datastream.  This parameter must be the
+              same as the value of filter_method used
+              in png_set_IHDR().
+
+It is also possible to influence how libpng chooses from among the
+available filters.  This is done in one or both of two ways - by
+telling it how important it is to keep the same filter for successive
+rows, and by telling it the relative computational costs of the filters.
+
+    double weights[3] = {1.5, 1.3, 1.1},
+       costs[PNG_FILTER_VALUE_LAST] =
+       {1.0, 1.3, 1.3, 1.5, 1.7};
+
+    png_set_filter_heuristics(png_ptr,
+       PNG_FILTER_HEURISTIC_WEIGHTED, 3,
+       weights, costs);
+
+The weights are multiplying factors that indicate to libpng that the
+row filter should be the same for successive rows unless another row filter
+is that many times better than the previous filter.  In the above example,
+if the previous 3 filters were SUB, SUB, NONE, the SUB filter could have a
+"sum of absolute differences" 1.5 x 1.3 times higher than other filters
+and still be chosen, while the NONE filter could have a sum 1.1 times
+higher than other filters and still be chosen.  Unspecified weights are
+taken to be 1.0, and the specified weights should probably be declining
+like those above in order to emphasize recent filters over older filters.
+
+The filter costs specify for each filter type a relative decoding cost
+to be considered when selecting row filters.  This means that filters
+with higher costs are less likely to be chosen over filters with lower
+costs, unless their "sum of absolute differences" is that much smaller.
+The costs do not necessarily reflect the exact computational speeds of
+the various filters, since this would unduly influence the final image
+size.
+
+Note that the numbers above were invented purely for this example and
+are given only to help explain the function usage.  Little testing has
+been done to find optimum values for either the costs or the weights.
+
+Removing unwanted object code
+
+There are a bunch of #define's in pngconf.h that control what parts of
+libpng are compiled.  All the defines end in _SUPPORTED.  If you are
+never going to use a capability, you can change the #define to #undef
+before recompiling libpng and save yourself code and data space, or
+you can turn off individual capabilities with defines that begin with
+PNG_NO_.
+
+You can also turn all of the transforms and ancillary chunk capabilities
+off en masse with compiler directives that define
+PNG_NO_READ[or WRITE]_TRANSFORMS, or PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS,
+or all four,
+along with directives to turn on any of the capabilities that you do
+want.  The PNG_NO_READ[or WRITE]_TRANSFORMS directives disable
+the extra transformations but still leave the library fully capable of reading
+and writing PNG files with all known public chunks
+Use of the PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS directive
+produces a library that is incapable of reading or writing ancillary chunks.
+If you are not using the progressive reading capability, you can
+turn that off with PNG_NO_PROGRESSIVE_READ (don't confuse
+this with the INTERLACING capability, which you'll still have).
+
+All the reading and writing specific code are in separate files, so the
+linker should only grab the files it needs.  However, if you want to
+make sure, or if you are building a stand alone library, all the
+reading files start with pngr and all the writing files start with
+pngw.  The files that don't match either (like png.c, pngtrans.c, etc.)
+are used for both reading and writing, and always need to be included.
+The progressive reader is in pngpread.c
+
+If you are creating or distributing a dynamically linked library (a .so
+or DLL file), you should not remove or disable any parts of the library,
+as this will cause applications linked with different versions of the
+library to fail if they call functions not available in your library.
+The size of the library itself should not be an issue, because only
+those sections that are actually used will be loaded into memory.
+
+Requesting debug printout
+
+The macro definition PNG_DEBUG can be used to request debugging
+printout.  Set it to an integer value in the range 0 to 3.  Higher
+numbers result in increasing amounts of debugging information.  The
+information is printed to the "stderr" file, unless another file
+name is specified in the PNG_DEBUG_FILE macro definition.
+
+When PNG_DEBUG > 0, the following functions (macros) become available:
+
+   png_debug(level, message)
+   png_debug1(level, message, p1)
+   png_debug2(level, message, p1, p2)
+
+in which "level" is compared to PNG_DEBUG to decide whether to print
+the message, "message" is the formatted string to be printed,
+and p1 and p2 are parameters that are to be embedded in the string
+according to printf-style formatting directives.  For example,
+
+   png_debug1(2, "foo=%d\n", foo);
+
+is expanded to
+
+   if(PNG_DEBUG > 2)
+     fprintf(PNG_DEBUG_FILE, "foo=%d\n", foo);
+
+When PNG_DEBUG is defined but is zero, the macros aren't defined, but you
+can still use PNG_DEBUG to control your own debugging:
+
+   #ifdef PNG_DEBUG
+       fprintf(stderr, ...
+   #endif
+
+When PNG_DEBUG = 1, the macros are defined, but only png_debug statements
+having level = 0 will be printed.  There aren't any such statements in
+this version of libpng, but if you insert some they will be printed.
+
+VI.  Runtime optimization
+
+A new feature in libpng 1.2.0 is the ability to dynamically switch between
+standard and optimized versions of some routines.  Currently these are
+limited to three computationally intensive tasks when reading PNG files:
+decoding row filters, expanding interlacing, and combining interlaced or
+transparent row data with previous row data.  Currently the optimized
+versions are available only for x86 (Intel, AMD, etc.) platforms with
+MMX support, though this may change in future versions.  (For example,
+the non-MMX assembler optimizations for zlib might become similarly
+runtime-selectable in future releases, in which case libpng could be
+extended to support them.  Alternatively, the compile-time choice of
+floating-point versus integer routines for gamma correction might become
+runtime-selectable.)
+
+Because such optimizations tend to be very platform- and compiler-dependent,
+both in how they are written and in how they perform, the new runtime code
+in libpng has been written to allow programs to query, enable, and disable
+either specific optimizations or all such optimizations.  For example, to
+enable all possible optimizations (bearing in mind that some "optimizations"
+may actually run more slowly in rare cases):
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       png_uint_32 mask, flags;
+
+       flags = png_get_asm_flags(png_ptr);
+       mask = png_get_asm_flagmask(PNG_SELECT_READ | PNG_SELECT_WRITE);
+       png_set_asm_flags(png_ptr, flags | mask);
+    #endif
+
+To enable only optimizations relevant to reading PNGs, use PNG_SELECT_READ
+by itself when calling png_get_asm_flagmask(); similarly for optimizing
+only writing.  To disable all optimizations:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       flags = png_get_asm_flags(png_ptr);
+       mask = png_get_asm_flagmask(PNG_SELECT_READ | PNG_SELECT_WRITE);
+       png_set_asm_flags(png_ptr, flags & ~mask);
+    #endif
+
+To enable or disable only MMX-related features, use png_get_mmx_flagmask()
+in place of png_get_asm_flagmask().  The mmx version takes one additional
+parameter:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       int selection = PNG_SELECT_READ | PNG_SELECT_WRITE;
+       int compilerID;
+
+       mask = png_get_mmx_flagmask(selection, &compilerID);
+    #endif
+
+On return, compilerID will indicate which version of the MMX assembler
+optimizations was compiled.  Currently two flavors exist:  Microsoft
+Visual C++ (compilerID == 1) and GNU C (a.k.a. gcc/gas, compilerID == 2).
+On non-x86 platforms or on systems compiled without MMX optimizations, a
+value of -1 is used.
+
+Note that both png_get_asm_flagmask() and png_get_mmx_flagmask() return
+all valid, settable optimization bits for the version of the library that's
+currently in use.  In the case of shared (dynamically linked) libraries,
+this may include optimizations that did not exist at the time the code was
+written and compiled.  It is also possible, of course, to enable only known,
+specific optimizations; for example:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       flags = PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
+             | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ;
+       png_set_asm_flags(png_ptr, flags);
+    #endif
+
+This method would enable only the MMX read-optimizations available at the
+time of libpng 1.2.0's release, regardless of whether a later version of
+the DLL were actually being used.  (Also note that these functions did not
+exist in versions older than 1.2.0, so any attempt to run a dynamically
+linked app on such an older version would fail.)
+
+To determine whether the processor supports MMX instructions at all, use
+the png_mmx_support() function:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       mmxsupport = png_mmx_support();
+    #endif
+
+It returns -1 if MMX support is not compiled into libpng, 0 if MMX code
+is compiled but MMX is not supported by the processor, or 1 if MMX support
+is fully available.  Note that png_mmx_support(), png_get_mmx_flagmask(),
+and png_get_asm_flagmask() all may be called without allocating and ini-
+tializing any PNG structures (for example, as part of a usage screen or
+"about" box).
+
+The following code can be used to prevent an application from using the
+thread_unsafe features, even if libpng was built with PNG_THREAD_UNSAFE_OK
+defined:
+
+#if defined(PNG_USE_PNGGCCRD) && defined(PNG_ASSEMBLER_CODE_SUPPORTED) \
+  && defined(PNG_THREAD_UNSAFE_OK)
+    /* Disable thread-unsafe features of pnggccrd */
+    if (png_access_version() >= 10200)
+    {
+      png_uint_32 mmx_disable_mask = 0;
+      png_uint_32 asm_flags;
+
+      mmx_disable_mask |= ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
+                          | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
+                          | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
+                          | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH );
+      asm_flags = png_get_asm_flags(png_ptr);
+      png_set_asm_flags(png_ptr, asm_flags & ~mmx_disable_mask);
+    }
+#endif
+
+For more extensive examples of runtime querying, enabling and disabling
+of optimized features, see contrib/gregbook/readpng2.c in the libpng
+source-code distribution.
+
+VII.  MNG support
+
+The MNG specification (available at http://www.libpng.org/pub/mng) allows
+certain extensions to PNG for PNG images that are embedded in MNG datastreams.
+Libpng can support some of these extensions.  To enable them, use the
+png_permit_mng_features() function:
+
+   feature_set = png_permit_mng_features(png_ptr, mask)
+   mask is a png_uint_32 containing the logical OR of the
+        features you want to enable.  These include
+        PNG_FLAG_MNG_EMPTY_PLTE
+        PNG_FLAG_MNG_FILTER_64
+        PNG_ALL_MNG_FEATURES
+   feature_set is a png_uint_32 that is the logical AND of
+      your mask with the set of MNG features that is
+      supported by the version of libpng that you are using.
+
+It is an error to use this function when reading or writing a standalone
+PNG file with the PNG 8-byte signature.  The PNG datastream must be wrapped
+in a MNG datastream.  As a minimum, it must have the MNG 8-byte signature
+and the MHDR and MEND chunks.  Libpng does not provide support for these
+or any other MNG chunks; your application must provide its own support for
+them.  You may wish to consider using libmng (available at
+http://www.libmng.com) instead.
+
+VIII.  Changes to Libpng from version 0.88
+
+It should be noted that versions of libpng later than 0.96 are not
+distributed by the original libpng author, Guy Schalnat, nor by
+Andreas Dilger, who had taken over from Guy during 1996 and 1997, and
+distributed versions 0.89 through 0.96, but rather by another member
+of the original PNG Group, Glenn Randers-Pehrson.  Guy and Andreas are
+still alive and well, but they have moved on to other things.
+
+The old libpng functions png_read_init(), png_write_init(),
+png_info_init(), png_read_destroy(), and png_write_destroy() have been
+moved to PNG_INTERNAL in version 0.95 to discourage their use.  These
+functions will be removed from libpng version 2.0.0.
+
+The preferred method of creating and initializing the libpng structures is
+via the png_create_read_struct(), png_create_write_struct(), and
+png_create_info_struct() because they isolate the size of the structures
+from the application, allow version error checking, and also allow the
+use of custom error handling routines during the initialization, which
+the old functions do not.  The functions png_read_destroy() and
+png_write_destroy() do not actually free the memory that libpng
+allocated for these structs, but just reset the data structures, so they
+can be used instead of png_destroy_read_struct() and
+png_destroy_write_struct() if you feel there is too much system overhead
+allocating and freeing the png_struct for each image read.
+
+Setting the error callbacks via png_set_message_fn() before
+png_read_init() as was suggested in libpng-0.88 is no longer supported
+because this caused applications that do not use custom error functions
+to fail if the png_ptr was not initialized to zero.  It is still possible
+to set the error callbacks AFTER png_read_init(), or to change them with
+png_set_error_fn(), which is essentially the same function, but with a new
+name to force compilation errors with applications that try to use the old
+method.
+
+Starting with version 1.0.7, you can find out which version of the library
+you are using at run-time:
+
+   png_uint_32 libpng_vn = png_access_version_number();
+
+The number libpng_vn is constructed from the major version, minor
+version with leading zero, and release number with leading zero,
+(e.g., libpng_vn for version 1.0.7 is 10007).
+
+You can also check which version of png.h you used when compiling your
+application:
+
+   png_uint_32 application_vn = PNG_LIBPNG_VER;
+
+IX. Y2K Compliance in libpng
+
+December 3, 2004
+
+Since the PNG Development group is an ad-hoc body, we can't make
+an official declaration.
+
+This is your unofficial assurance that libpng from version 0.71 and
+upward through 1.2.8 are Y2K compliant.  It is my belief that earlier
+versions were also Y2K compliant.
+
+Libpng only has three year fields.  One is a 2-byte unsigned integer that
+will hold years up to 65535.  The other two hold the date in text
+format, and will hold years up to 9999.
+
+The integer is
+    "png_uint_16 year" in png_time_struct.
+
+The strings are
+    "png_charp time_buffer" in png_struct and
+    "near_time_buffer", which is a local character string in png.c.
+
+There are seven time-related functions:
+
+    png_convert_to_rfc_1123() in png.c
+      (formerly png_convert_to_rfc_1152() in error)
+    png_convert_from_struct_tm() in pngwrite.c, called
+      in pngwrite.c
+    png_convert_from_time_t() in pngwrite.c
+    png_get_tIME() in pngget.c
+    png_handle_tIME() in pngrutil.c, called in pngread.c
+    png_set_tIME() in pngset.c
+    png_write_tIME() in pngwutil.c, called in pngwrite.c
+
+All appear to handle dates properly in a Y2K environment.  The
+png_convert_from_time_t() function calls gmtime() to convert from system
+clock time, which returns (year - 1900), which we properly convert to
+the full 4-digit year.  There is a possibility that applications using
+libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
+function, or that they are incorrectly passing only a 2-digit year
+instead of "year - 1900" into the png_convert_from_struct_tm() function,
+but this is not under our control.  The libpng documentation has always
+stated that it works with 4-digit years, and the APIs have been
+documented as such.
+
+The tIME chunk itself is also Y2K compliant.  It uses a 2-byte unsigned
+integer to hold the year, and can hold years as large as 65535.
+
+zlib, upon which libpng depends, is also Y2K compliant.  It contains
+no date-related code.
+
+
+   Glenn Randers-Pehrson
+   libpng maintainer
+   PNG Development Group
diff --git a/gs/libpng/libpngpf.3 b/gs/libpng/libpngpf.3
new file mode 100644
index 000000000..d196d70c4
--- /dev/null
+++ b/gs/libpng/libpngpf.3
@@ -0,0 +1,1096 @@
+.TH LIBPNGPF 3 "December 3, 2004"
+.SH NAME
+libpng \- Portable Network Graphics (PNG) Reference Library 1.2.8
+(private functions)
+.SH SYNOPSIS
+\fB\fB#include <png.h>\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_build_gamma_table (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_build_grayscale_palette (int \fP\fI\fP\fIbit_depth\fP\fB\fP\fB, png_colorp \fI\fIpalette\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_calculate_crc (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIptr\fP\fB\fP\fB, png_size_t \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_check_chunk_name (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fI\fIchunk_name\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBpng_size_t png_check_keyword (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_charp \fP\fI\fP\fIkey\fP\fB\fP\fB, png_charpp \fI\fInew_key\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_combine_row (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, int \fI\fImask\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_correct_palette (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_colorp \fP\fI\fP\fIpalette\fP\fB\fP\fB, int \fI\fInum_palette\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBint png_crc_error (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBint png_crc_finish (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIskip\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_crc_read (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIbuf\fP\fB\fP\fB, png_size_t \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBpng_voidp png_create_struct (int \fI\fItype\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBpng_voidp png_create_struct_2 (int \fP\fI\fP\fItype\fP\fB\fP\fB, png_malloc_ptr \fP\fI\fP\fImalloc_fn\fP\fB\fP\fB, png_voidp \fI\fImem_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBpng_charp png_decompress_chunk (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, int \fP\fI\fP\fIcomp_type\fP\fB\fP\fB, png_charp \fP\fI\fP\fIchunkdata\fP\fB\fP\fB, png_size_t \fP\fI\fP\fIchunklength\fP\fB\fP\fB, png_size_t \fP\fI\fP\fIprefix_length\fP\fB\fP\fB, png_size_t \fI\fI*data_length\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_destroy_struct (png_voidp \fI\fIstruct_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_destroy_struct_2 (png_voidp \fP\fI\fP\fIstruct_ptr\fP\fB\fP\fB, png_free_ptr \fP\fI\fP\fIfree_fn\fP\fB\fP\fB, png_voidp \fI\fImem_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_background (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, png_color_16p \fP\fI\fP\fItrans_values\fP\fB\fP\fB, png_color_16p \fP\fI\fP\fIbackground\fP\fB\fP\fB, png_color_16p \fP\fI\fP\fIbackground_1\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIgamma_table\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIgamma_from_1\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIgamma_to_1\fP\fB\fP\fB, png_uint_16pp \fP\fI\fP\fIgamma_16\fP\fB\fP\fB, png_uint_16pp \fP\fI\fP\fIgamma_16_from_1\fP\fB\fP\fB, png_uint_16pp \fP\fI\fP\fIgamma_16_to_1\fP\fB\fP\fB, int \fI\fIgamma_shift\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_bgr (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_chop (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_dither (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIpalette_lookup\fP\fB\fP\fB, png_bytep \fI\fIdither_lookup\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_expand (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, png_color_16p \fI\fItrans_value\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_expand_palette (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, png_colorp \fP\fI\fP\fIpalette\fP\fB\fP\fB, png_bytep \fP\fI\fP\fItrans\fP\fB\fP\fB, int \fI\fInum_trans\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_gamma (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIgamma_table\fP\fB\fP\fB, png_uint_16pp \fP\fI\fP\fIgamma_16_table\fP\fB\fP\fB, int \fI\fIgamma_shift\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_gray_to_rgb (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_invert (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_pack (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, png_uint_32 \fI\fIbit_depth\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_packswap (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_read_filler (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIfiller\fP\fB\fP\fB, png_uint_32 \fI\fIflags\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_read_interlace (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, int \fP\fI\fP\fIpass\fP\fB\fP\fB, png_uint_32 \fI\fItransformations\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_read_invert_alpha (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_read_swap_alpha (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_read_transformations (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBint png_do_rgb_to_gray (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_shift (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, png_color_8p \fI\fIbit_depth\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_strip_filler (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, png_uint_32 \fI\fIflags\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_swap (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_unpack (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_unshift (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, png_color_8p \fI\fIsig_bits\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_write_interlace (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, int \fI\fIpass\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_write_invert_alpha (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_write_swap_alpha (png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_do_write_transformations (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid *png_far_to_near (png_structp png_ptr,png_voidp \fP\fI\fP\fIptr\fP\fB\fP\fB, int \fI\fIcheck\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_flush (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBpng_int_32 png_get_int_32 (png_bytep \fI\fIbuf\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBpng_uint_16 png_get_uint_16 (png_bytep \fI\fIbuf\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBpng_uint_32 png_get_uint_31 (png_bytep \fI\fIbuf\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBpng_uint_32 png_get_uint_32 (png_bytep \fI\fIbuf\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_bKGD (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_cHRM (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_gAMA (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_hIST (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_IEND (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_IHDR (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_iCCP (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_iTXt (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_oFFs (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_pCAL (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_pHYs (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_PLTE (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_sBIT (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_sCAL (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_sPLT (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_sRGB (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_tEXt (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_tIME (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_tRNS (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_unknown (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_handle_zTXt (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_info_destroy (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fI\fIinfo_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_init_mmx_flags (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_init_read_transformations (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_process_IDAT_data (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIbuffer\fP\fB\fP\fB, png_size_t \fI\fIbuffer_length\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_process_some_data (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fI\fIinfo_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_check_crc (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_crc_finish (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_crc_skip (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_fill_buffer (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIbuffer\fP\fB\fP\fB, png_size_t \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_handle_tEXt (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_handle_unknown (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_handle_zTXt (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_have_end (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fI\fIinfo_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_have_info (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fI\fIinfo_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_have_row (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fI\fIrow\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_process_row (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_read_chunk (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fI\fIinfo_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_read_end (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fI\fIinfo_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_read_IDAT (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_read_sig (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fI\fIinfo_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_read_tEXt (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fI\fIinfo_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_read_zTXt (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fI\fIinfo_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_restore_buffer (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIbuffer\fP\fB\fP\fB, png_size_t \fI\fIbuffer_length\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_push_save_buffer (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_read_data (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIdata\fP\fB\fP\fB, png_size_t \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_read_filter_row (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_row_infop \fP\fI\fP\fIrow_info\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIrow\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIprev_row\fP\fB\fP\fB, int \fI\fIfilter\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_read_finish_row (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_read_push_finish_row (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_read_start_row (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_read_transform_info (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fI\fIinfo_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_reset_crc (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_save_int_32 (png_bytep \fP\fI\fP\fIbuf\fP\fB\fP\fB, png_int_32 \fI\fIi\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_save_uint_16 (png_bytep \fP\fI\fP\fIbuf\fP\fB\fP\fB, unsigned int \fI\fIi\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_save_uint_32 (png_bytep \fP\fI\fP\fIbuf\fP\fB\fP\fB, png_uint_32 \fI\fIi\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBint png_set_text_2 (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_infop \fP\fI\fP\fIinfo_ptr\fP\fB\fP\fB, png_textp \fP\fI\fP\fItext_ptr\fP\fB\fP\fB, int \fI\fInum_text\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_cHRM (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, double \fP\fI\fP\fIwhite_x\fP\fB\fP\fB, double \fP\fI\fP\fIwhite_y\fP\fB\fP\fB, double \fP\fI\fP\fIred_x\fP\fB\fP\fB, double \fP\fI\fP\fIred_y\fP\fB\fP\fB, double \fP\fI\fP\fIgreen_x\fP\fB\fP\fB, double \fP\fI\fP\fIgreen_y\fP\fB\fP\fB, double \fP\fI\fP\fIblue_x\fP\fB\fP\fB, double \fI\fIblue_y\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_cHRM_fixed (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIwhite_x\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIwhite_y\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIred_x\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIred_y\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIgreen_x\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIgreen_y\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIblue_x\fP\fB\fP\fB, png_uint_32 \fI\fIblue_y\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_data (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIdata\fP\fB\fP\fB, png_size_t \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_filtered_row (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fI\fIfiltered_row\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_find_filter (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_row_infop \fI\fIrow_info\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_finish_row (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_gAMA (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, double \fI\fIfile_gamma\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_gAMA_fixed (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_uint_32 \fI\fIint_file_gamma\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_hIST (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_uint_16p \fP\fI\fP\fIhist\fP\fB\fP\fB, int \fI\fInum_hist\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_iCCP (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_charp \fP\fI\fP\fIname\fP\fB\fP\fB, int \fP\fI\fP\fIcompression_type\fP\fB\fP\fB, png_charp \fP\fI\fP\fIprofile\fP\fB\fP\fB, int \fI\fIproflen\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_IDAT (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fP\fI\fP\fIdata\fP\fB\fP\fB, png_size_t \fI\fIlength\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_IEND (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_IHDR (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIwidth\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIheight\fP\fB\fP\fB, int \fP\fI\fP\fIbit_depth\fP\fB\fP\fB, int \fP\fI\fP\fIcolor_type\fP\fB\fP\fB, int \fP\fI\fP\fIcompression_type\fP\fB\fP\fB, int \fP\fI\fP\fIfilter_type\fP\fB\fP\fB, int \fI\fIinterlace_type\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_iTXt (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, int \fP\fI\fP\fIcompression\fP\fB\fP\fB, png_charp \fP\fI\fP\fIkey\fP\fB\fP\fB, png_charp \fP\fI\fP\fIlang\fP\fB\fP\fB, png_charp \fP\fI\fP\fItranslated_key\fP\fB\fP\fB, png_charp \fI\fItext\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_oFFs (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIx_offset\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIy_offset\fP\fB\fP\fB, int \fI\fIunit_type\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_pCAL (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_charp \fP\fI\fP\fIpurpose\fP\fB\fP\fB, png_int_32 \fP\fI\fP\fIX0\fP\fB\fP\fB, png_int_32 \fP\fI\fP\fIX1\fP\fB\fP\fB, int \fP\fI\fP\fItype\fP\fB\fP\fB, int \fP\fI\fP\fInparams\fP\fB\fP\fB, png_charp \fP\fI\fP\fIunits\fP\fB\fP\fB, png_charpp \fI\fIparams\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_pHYs (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIx_pixels_per_unit\fP\fB\fP\fB, png_uint_32 \fP\fI\fP\fIy_pixels_per_unit\fP\fB\fP\fB, int \fI\fIunit_type\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_PLTE (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_colorp \fP\fI\fP\fIpalette\fP\fB\fP\fB, png_uint_32 \fI\fInum_pal\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_sBIT (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_color_8p \fP\fI\fP\fIsbit\fP\fB\fP\fB, int \fI\fIcolor_type\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_sCAL (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_charp \fP\fI\fP\fIunit\fP\fB\fP\fB, double \fP\fI\fP\fIwidth\fP\fB\fP\fB, double \fI\fIheight\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_sCAL_s (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_charp \fP\fI\fP\fIunit\fP\fB\fP\fB, png_charp \fP\fI\fP\fIwidth\fP\fB\fP\fB, png_charp \fI\fIheight\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_sig (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_sRGB (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, int \fI\fIintent\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_sPLT (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_spalette_p \fI\fIpalette\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_start_row (png_structp \fI\fIpng_ptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_tEXt (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_charp \fP\fI\fP\fIkey\fP\fB\fP\fB, png_charp \fP\fI\fP\fItext\fP\fB\fP\fB, png_size_t \fI\fItext_len\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_tIME (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_timep \fI\fImod_time\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_tRNS (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_bytep \fP\fI\fP\fItrans\fP\fB\fP\fB, png_color_16p \fP\fI\fP\fIvalues\fP\fB\fP\fB, int \fP\fI\fP\fInumber\fP\fB\fP\fB, int \fI\fIcolor_type\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_write_zTXt (png_structp \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, png_charp \fP\fI\fP\fIkey\fP\fB\fP\fB, png_charp \fP\fI\fP\fItext\fP\fB\fP\fB, png_size_t \fP\fI\fP\fItext_len\fP\fB\fP\fB, int \fI\fIcompression\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoidpf png_zalloc (voidpf \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, uInt \fP\fI\fP\fIitems\fP\fB\fP\fB, uInt \fI\fIsize\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+\fB\fBvoid png_zfree (voidpf \fP\fI\fP\fIpng_ptr\fP\fB\fP\fB, voidpf \fI\fIptr\fP\fB\fP\fB);\fP\fP
+
+\fI\fB
+
+\fI\fB\fI\fB
+
+\fI\fB
+
+.SH DESCRIPTION
+The functions listed above are used privately by libpng
+and are not recommended for use by applications.  They are
+not "exported" to applications using shared libraries.  They
+are listed alphabetically here as an aid to libpng maintainers.
+See png.h for more information on these functions.
+
+.SH SEE ALSO
+libpng(3), png(5)
+.SH AUTHOR
+Glenn Randers-Pehrson
diff --git a/gs/libpng/png.5 b/gs/libpng/png.5
new file mode 100644
index 000000000..db7c83416
--- /dev/null
+++ b/gs/libpng/png.5
@@ -0,0 +1,74 @@
+.TH PNG 5 "December 3, 2004"
+.SH NAME
+png \- Portable Network Graphics (PNG) format
+.SH DESCRIPTION
+PNG (Portable Network Graphics) is an extensible file format for the
+lossless, portable, well-compressed storage of raster images. PNG provides
+a patent-free replacement for GIF and can also replace many
+common uses of TIFF. Indexed-color, grayscale, and truecolor images are
+supported, plus an optional alpha channel. Sample depths range from
+1 to 16 bits.
+.br
+
+PNG is designed to work well in online viewing applications, such as the
+World Wide Web, so it is fully streamable with a progressive display
+option. PNG is robust, providing both full file integrity checking and
+fast, simple detection of common transmission errors. Also, PNG can store
+gamma and chromaticity data for improved color matching on heterogeneous
+platforms.
+
+.SH "SEE ALSO"
+.IR libpng(3), zlib(3), deflate(5), and zlib(5)
+.LP
+PNG specification (second edition), November 2003:
+.IP
+.br
+  <http://www.w3.org/TR/2003/REC-PNG-20031110/
+PNG 1.2 specification, July 1999:
+.IP
+.br
+http://www.libpng.org/pub/png
+.LP
+PNG 1.0 specification, October 1996:
+.IP
+.br
+RFC 2083
+.IP
+.br
+ftp://ds.internic.net/rfc/rfc2083.txt
+.br
+or (as a W3C Recommendation) at
+.br
+http://www.w3.org/TR/REC-png.html
+.SH AUTHORS
+This man page: Glenn Randers-Pehrson
+.LP
+Portable Network Graphics (PNG) Specification (Second Edition)
+Information technology - Computer graphics and image processing -
+Portable Network Graphics (PNG): Functional specification.
+ISO/IEC 15948:2003 (E) (November 10, 2003): David Duce and others.
+.LP
+Portable Network Graphics (PNG) Specification Version 1.2 (July 8, 1999):
+Glenn Randers-Pehrson and others (png-list).
+.LP
+Portable Network Graphics (PNG) Specification Version 1.0 (October 1, 1996):
+Thomas Boutell and others (png-list).
+.LP
+
+
+.SH COPYRIGHT NOTICE
+.LP
+This man page is Copyright (c) 1998-2004 Glenn Randers-Pehrson.  See png.h
+for conditions of use and distribution.
+.LP
+The PNG Specification (Second Edition) is
+Copyright (c) 2003 W3C. (MIT, ERCIM, Keio), All Rights Reserved.
+.LP
+The PNG-1.2 specification is copyright (c) 1999 Glenn Randers-Pehrson.
+See the specification for conditions of use and distribution.
+.LP
+The PNG-1.0 specification is copyright (c) 1996 Massachusetts Institute of
+Technology.  See the specification for conditions of use and distribution.
+.LP
+.\" end of man page
+
diff --git a/gs/libpng/png.c b/gs/libpng/png.c
new file mode 100644
index 000000000..608ea2ce7
--- /dev/null
+++ b/gs/libpng/png.c
@@ -0,0 +1,828 @@
+
+/* png.c - location for general purpose libpng functions
+ *
+ * libpng version 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#define PNG_NO_EXTERN
+#include "png.h"
+
+/* Generate a compiler error if there is an old png.h in the search path. */
+typedef version_1_2_8 Your_png_h_is_not_version_1_2_8;
+
+/* Version information for C files.  This had better match the version
+ * string defined in png.h.  */
+
+#ifdef PNG_USE_GLOBAL_ARRAYS
+/* png_libpng_ver was changed to a function in version 1.0.5c */
+const char png_libpng_ver[18] = PNG_LIBPNG_VER_STRING;
+
+/* png_sig was changed to a function in version 1.0.5c */
+/* Place to hold the signature string for a PNG file. */
+const png_byte FARDATA png_sig[8] = {137, 80, 78, 71, 13, 10, 26, 10};
+
+/* Invoke global declarations for constant strings for known chunk types */
+PNG_IHDR;
+PNG_IDAT;
+PNG_IEND;
+PNG_PLTE;
+PNG_bKGD;
+PNG_cHRM;
+PNG_gAMA;
+PNG_hIST;
+PNG_iCCP;
+PNG_iTXt;
+PNG_oFFs;
+PNG_pCAL;
+PNG_sCAL;
+PNG_pHYs;
+PNG_sBIT;
+PNG_sPLT;
+PNG_sRGB;
+PNG_tEXt;
+PNG_tIME;
+PNG_tRNS;
+PNG_zTXt;
+
+/* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+/* start of interlace block */
+const int FARDATA png_pass_start[] = {0, 4, 0, 2, 0, 1, 0};
+
+/* offset to next interlace block */
+const int FARDATA png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
+
+/* start of interlace block in the y direction */
+const int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
+
+/* offset to next interlace block in the y direction */
+const int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
+
+/* width of interlace block (used in assembler routines only) */
+#ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
+const int FARDATA png_pass_width[] = {8, 4, 4, 2, 2, 1, 1};
+#endif
+
+/* Height of interlace block.  This is not currently used - if you need
+ * it, uncomment it here and in png.h
+const int FARDATA png_pass_height[] = {8, 8, 4, 4, 2, 2, 1};
+*/
+
+/* Mask to determine which pixels are valid in a pass */
+const int FARDATA png_pass_mask[] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
+
+/* Mask to determine which pixels to overwrite while displaying */
+const int FARDATA png_pass_dsp_mask[]
+   = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
+
+#endif /* PNG_USE_GLOBAL_ARRAYS */
+
+/* Tells libpng that we have already handled the first "num_bytes" bytes
+ * of the PNG file signature.  If the PNG data is embedded into another
+ * stream we can set num_bytes = 8 so that libpng will not attempt to read
+ * or write any of the magic bytes before it starts on the IHDR.
+ */
+
+void PNGAPI
+png_set_sig_bytes(png_structp png_ptr, int num_bytes)
+{
+   png_debug(1, "in png_set_sig_bytes\n");
+   if (num_bytes > 8)
+      png_error(png_ptr, "Too many bytes for PNG signature.");
+
+   png_ptr->sig_bytes = (png_byte)(num_bytes < 0 ? 0 : num_bytes);
+}
+
+/* Checks whether the supplied bytes match the PNG signature.  We allow
+ * checking less than the full 8-byte signature so that those apps that
+ * already read the first few bytes of a file to determine the file type
+ * can simply check the remaining bytes for extra assurance.  Returns
+ * an integer less than, equal to, or greater than zero if sig is found,
+ * respectively, to be less than, to match, or be greater than the correct
+ * PNG signature (this is the same behaviour as strcmp, memcmp, etc).
+ */
+int PNGAPI
+png_sig_cmp(png_bytep sig, png_size_t start, png_size_t num_to_check)
+{
+   png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
+   if (num_to_check > 8)
+      num_to_check = 8;
+   else if (num_to_check < 1)
+      return (0);
+
+   if (start > 7)
+      return (0);
+
+   if (start + num_to_check > 8)
+      num_to_check = 8 - start;
+
+   return ((int)(png_memcmp(&sig[start], &png_signature[start], num_to_check)));
+}
+
+/* (Obsolete) function to check signature bytes.  It does not allow one
+ * to check a partial signature.  This function might be removed in the
+ * future - use png_sig_cmp().  Returns true (nonzero) if the file is a PNG.
+ */
+int PNGAPI
+png_check_sig(png_bytep sig, int num)
+{
+  return ((int)!png_sig_cmp(sig, (png_size_t)0, (png_size_t)num));
+}
+
+/* Function to allocate memory for zlib and clear it to 0. */
+#ifdef PNG_1_0_X
+voidpf PNGAPI
+#else
+voidpf /* private */
+#endif
+png_zalloc(voidpf png_ptr, uInt items, uInt size)
+{
+   png_voidp ptr;
+   png_structp p=png_ptr;
+   png_uint_32 save_flags=p->flags;
+   png_uint_32 num_bytes;
+
+   if (items > PNG_UINT_32_MAX/size)
+   {
+     png_warning (png_ptr, "Potential overflow in png_zalloc()");
+     return (NULL);
+   }
+   num_bytes = (png_uint_32)items * size;
+
+   p->flags|=PNG_FLAG_MALLOC_NULL_MEM_OK;
+   ptr = (png_voidp)png_malloc((png_structp)png_ptr, num_bytes);
+   p->flags=save_flags;
+
+#if defined(PNG_1_0_X) && !defined(PNG_NO_ZALLOC_ZERO)
+   if (ptr == NULL)
+       return ((voidpf)ptr);
+
+   if (num_bytes > (png_uint_32)0x8000L)
+   {
+      png_memset(ptr, 0, (png_size_t)0x8000L);
+      png_memset((png_bytep)ptr + (png_size_t)0x8000L, 0,
+         (png_size_t)(num_bytes - (png_uint_32)0x8000L));
+   }
+   else
+   {
+      png_memset(ptr, 0, (png_size_t)num_bytes);
+   }
+#endif
+   return ((voidpf)ptr);
+}
+
+/* function to free memory for zlib */
+#ifdef PNG_1_0_X
+void PNGAPI
+#else
+void /* private */
+#endif
+png_zfree(voidpf png_ptr, voidpf ptr)
+{
+   png_free((png_structp)png_ptr, (png_voidp)ptr);
+}
+
+/* Reset the CRC variable to 32 bits of 1's.  Care must be taken
+ * in case CRC is > 32 bits to leave the top bits 0.
+ */
+void /* PRIVATE */
+png_reset_crc(png_structp png_ptr)
+{
+   png_ptr->crc = crc32(0, Z_NULL, 0);
+}
+
+/* Calculate the CRC over a section of data.  We can only pass as
+ * much data to this routine as the largest single buffer size.  We
+ * also check that this data will actually be used before going to the
+ * trouble of calculating it.
+ */
+void /* PRIVATE */
+png_calculate_crc(png_structp png_ptr, png_bytep ptr, png_size_t length)
+{
+   int need_crc = 1;
+
+   if (png_ptr->chunk_name[0] & 0x20)                     /* ancillary */
+   {
+      if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
+          (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
+         need_crc = 0;
+   }
+   else                                                    /* critical */
+   {
+      if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE)
+         need_crc = 0;
+   }
+
+   if (need_crc)
+      png_ptr->crc = crc32(png_ptr->crc, ptr, (uInt)length);
+}
+
+/* Allocate the memory for an info_struct for the application.  We don't
+ * really need the png_ptr, but it could potentially be useful in the
+ * future.  This should be used in favour of malloc(png_sizeof(png_info))
+ * and png_info_init() so that applications that want to use a shared
+ * libpng don't have to be recompiled if png_info changes size.
+ */
+png_infop PNGAPI
+png_create_info_struct(png_structp png_ptr)
+{
+   png_infop info_ptr;
+
+   png_debug(1, "in png_create_info_struct\n");
+   if(png_ptr == NULL) return (NULL);
+#ifdef PNG_USER_MEM_SUPPORTED
+   info_ptr = (png_infop)png_create_struct_2(PNG_STRUCT_INFO,
+      png_ptr->malloc_fn, png_ptr->mem_ptr);
+#else
+   info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO);
+#endif
+   if (info_ptr != NULL)
+      png_info_init_3(&info_ptr, png_sizeof(png_info));
+
+   return (info_ptr);
+}
+
+/* This function frees the memory associated with a single info struct.
+ * Normally, one would use either png_destroy_read_struct() or
+ * png_destroy_write_struct() to free an info struct, but this may be
+ * useful for some applications.
+ */
+void PNGAPI
+png_destroy_info_struct(png_structp png_ptr, png_infopp info_ptr_ptr)
+{
+   png_infop info_ptr = NULL;
+
+   png_debug(1, "in png_destroy_info_struct\n");
+   if (info_ptr_ptr != NULL)
+      info_ptr = *info_ptr_ptr;
+
+   if (info_ptr != NULL)
+   {
+      png_info_destroy(png_ptr, info_ptr);
+
+#ifdef PNG_USER_MEM_SUPPORTED
+      png_destroy_struct_2((png_voidp)info_ptr, png_ptr->free_fn,
+          png_ptr->mem_ptr);
+#else
+      png_destroy_struct((png_voidp)info_ptr);
+#endif
+      *info_ptr_ptr = NULL;
+   }
+}
+
+/* Initialize the info structure.  This is now an internal function (0.89)
+ * and applications using it are urged to use png_create_info_struct()
+ * instead.
+ */
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+#undef png_info_init
+void PNGAPI
+png_info_init(png_infop info_ptr)
+{
+   /* We only come here via pre-1.0.12-compiled applications */
+   png_info_init_3(&info_ptr, 0);
+}
+#endif
+
+void PNGAPI
+png_info_init_3(png_infopp ptr_ptr, png_size_t png_info_struct_size)
+{
+   png_infop info_ptr = *ptr_ptr;
+
+   png_debug(1, "in png_info_init_3\n");
+
+   if(png_sizeof(png_info) > png_info_struct_size)
+     {
+       png_destroy_struct(info_ptr);
+       info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO);
+       *ptr_ptr = info_ptr;
+     }
+
+   /* set everything to 0 */
+   png_memset(info_ptr, 0, png_sizeof (png_info));
+}
+
+#ifdef PNG_FREE_ME_SUPPORTED
+void PNGAPI
+png_data_freer(png_structp png_ptr, png_infop info_ptr,
+   int freer, png_uint_32 mask)
+{
+   png_debug(1, "in png_data_freer\n");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+   if(freer == PNG_DESTROY_WILL_FREE_DATA)
+      info_ptr->free_me |= mask;
+   else if(freer == PNG_USER_WILL_FREE_DATA)
+      info_ptr->free_me &= ~mask;
+   else
+      png_warning(png_ptr,
+         "Unknown freer parameter in png_data_freer.");
+}
+#endif
+
+void PNGAPI
+png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask,
+   int num)
+{
+   png_debug(1, "in png_free_data\n");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+#if defined(PNG_TEXT_SUPPORTED)
+/* free text item num or (if num == -1) all text items */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_TEXT) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_TEXT)
+#endif
+{
+   if (num != -1)
+   {
+     if (info_ptr->text && info_ptr->text[num].key)
+     {
+         png_free(png_ptr, info_ptr->text[num].key);
+         info_ptr->text[num].key = NULL;
+     }
+   }
+   else
+   {
+       int i;
+       for (i = 0; i < info_ptr->num_text; i++)
+           png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, i);
+       png_free(png_ptr, info_ptr->text);
+       info_ptr->text = NULL;
+       info_ptr->num_text=0;
+   }
+}
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+/* free any tRNS entry */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_TRNS) & info_ptr->free_me)
+#else
+if ((mask & PNG_FREE_TRNS) && (png_ptr->flags & PNG_FLAG_FREE_TRNS))
+#endif
+{
+    png_free(png_ptr, info_ptr->trans);
+    info_ptr->valid &= ~PNG_INFO_tRNS;
+#ifndef PNG_FREE_ME_SUPPORTED
+    png_ptr->flags &= ~PNG_FLAG_FREE_TRNS;
+#endif
+    info_ptr->trans = NULL;
+}
+#endif
+
+#if defined(PNG_sCAL_SUPPORTED)
+/* free any sCAL entry */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_SCAL) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_SCAL)
+#endif
+{
+#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
+    png_free(png_ptr, info_ptr->scal_s_width);
+    png_free(png_ptr, info_ptr->scal_s_height);
+    info_ptr->scal_s_width = NULL;
+    info_ptr->scal_s_height = NULL;
+#endif
+    info_ptr->valid &= ~PNG_INFO_sCAL;
+}
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+/* free any pCAL entry */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_PCAL) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_PCAL)
+#endif
+{
+    png_free(png_ptr, info_ptr->pcal_purpose);
+    png_free(png_ptr, info_ptr->pcal_units);
+    info_ptr->pcal_purpose = NULL;
+    info_ptr->pcal_units = NULL;
+    if (info_ptr->pcal_params != NULL)
+    {
+        int i;
+        for (i = 0; i < (int)info_ptr->pcal_nparams; i++)
+        {
+          png_free(png_ptr, info_ptr->pcal_params[i]);
+          info_ptr->pcal_params[i]=NULL;
+        }
+        png_free(png_ptr, info_ptr->pcal_params);
+        info_ptr->pcal_params = NULL;
+    }
+    info_ptr->valid &= ~PNG_INFO_pCAL;
+}
+#endif
+
+#if defined(PNG_iCCP_SUPPORTED)
+/* free any iCCP entry */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_ICCP) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_ICCP)
+#endif
+{
+    png_free(png_ptr, info_ptr->iccp_name);
+    png_free(png_ptr, info_ptr->iccp_profile);
+    info_ptr->iccp_name = NULL;
+    info_ptr->iccp_profile = NULL;
+    info_ptr->valid &= ~PNG_INFO_iCCP;
+}
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+/* free a given sPLT entry, or (if num == -1) all sPLT entries */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_SPLT) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_SPLT)
+#endif
+{
+   if (num != -1)
+   {
+      if(info_ptr->splt_palettes)
+      {
+          png_free(png_ptr, info_ptr->splt_palettes[num].name);
+          png_free(png_ptr, info_ptr->splt_palettes[num].entries);
+          info_ptr->splt_palettes[num].name = NULL;
+          info_ptr->splt_palettes[num].entries = NULL;
+      }
+   }
+   else
+   {
+       if(info_ptr->splt_palettes_num)
+       {
+         int i;
+         for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
+            png_free_data(png_ptr, info_ptr, PNG_FREE_SPLT, i);
+
+         png_free(png_ptr, info_ptr->splt_palettes);
+         info_ptr->splt_palettes = NULL;
+         info_ptr->splt_palettes_num = 0;
+       }
+       info_ptr->valid &= ~PNG_INFO_sPLT;
+   }
+}
+#endif
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_UNKN) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_UNKN)
+#endif
+{
+   if (num != -1)
+   {
+       if(info_ptr->unknown_chunks)
+       {
+          png_free(png_ptr, info_ptr->unknown_chunks[num].data);
+          info_ptr->unknown_chunks[num].data = NULL;
+       }
+   }
+   else
+   {
+       int i;
+
+       if(info_ptr->unknown_chunks_num)
+       {
+         for (i = 0; i < (int)info_ptr->unknown_chunks_num; i++)
+            png_free_data(png_ptr, info_ptr, PNG_FREE_UNKN, i);
+
+         png_free(png_ptr, info_ptr->unknown_chunks);
+         info_ptr->unknown_chunks = NULL;
+         info_ptr->unknown_chunks_num = 0;
+       }
+   }
+}
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+/* free any hIST entry */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_HIST)  & info_ptr->free_me)
+#else
+if ((mask & PNG_FREE_HIST) && (png_ptr->flags & PNG_FLAG_FREE_HIST))
+#endif
+{
+    png_free(png_ptr, info_ptr->hist);
+    info_ptr->hist = NULL;
+    info_ptr->valid &= ~PNG_INFO_hIST;
+#ifndef PNG_FREE_ME_SUPPORTED
+    png_ptr->flags &= ~PNG_FLAG_FREE_HIST;
+#endif
+}
+#endif
+
+/* free any PLTE entry that was internally allocated */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_PLTE) & info_ptr->free_me)
+#else
+if ((mask & PNG_FREE_PLTE) && (png_ptr->flags & PNG_FLAG_FREE_PLTE))
+#endif
+{
+    png_zfree(png_ptr, info_ptr->palette);
+    info_ptr->palette = NULL;
+    info_ptr->valid &= ~PNG_INFO_PLTE;
+#ifndef PNG_FREE_ME_SUPPORTED
+    png_ptr->flags &= ~PNG_FLAG_FREE_PLTE;
+#endif
+    info_ptr->num_palette = 0;
+}
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+/* free any image bits attached to the info structure */
+#ifdef PNG_FREE_ME_SUPPORTED
+if ((mask & PNG_FREE_ROWS) & info_ptr->free_me)
+#else
+if (mask & PNG_FREE_ROWS)
+#endif
+{
+    if(info_ptr->row_pointers)
+    {
+       int row;
+       for (row = 0; row < (int)info_ptr->height; row++)
+       {
+          png_free(png_ptr, info_ptr->row_pointers[row]);
+          info_ptr->row_pointers[row]=NULL;
+       }
+       png_free(png_ptr, info_ptr->row_pointers);
+       info_ptr->row_pointers=NULL;
+    }
+    info_ptr->valid &= ~PNG_INFO_IDAT;
+}
+#endif
+
+#ifdef PNG_FREE_ME_SUPPORTED
+   if(num == -1)
+     info_ptr->free_me &= ~mask;
+   else
+     info_ptr->free_me &= ~(mask & ~PNG_FREE_MUL);
+#endif
+}
+
+/* This is an internal routine to free any memory that the info struct is
+ * pointing to before re-using it or freeing the struct itself.  Recall
+ * that png_free() checks for NULL pointers for us.
+ */
+void /* PRIVATE */
+png_info_destroy(png_structp png_ptr, png_infop info_ptr)
+{
+   png_debug(1, "in png_info_destroy\n");
+
+   png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+   if (png_ptr->num_chunk_list)
+   {
+       png_free(png_ptr, png_ptr->chunk_list);
+       png_ptr->chunk_list=NULL;
+       png_ptr->num_chunk_list=0;
+   }
+#endif
+
+   png_info_init_3(&info_ptr, png_sizeof(png_info));
+}
+
+/* This function returns a pointer to the io_ptr associated with the user
+ * functions.  The application should free any memory associated with this
+ * pointer before png_write_destroy() or png_read_destroy() are called.
+ */
+png_voidp PNGAPI
+png_get_io_ptr(png_structp png_ptr)
+{
+   return (png_ptr->io_ptr);
+}
+
+#if !defined(PNG_NO_STDIO)
+/* Initialize the default input/output functions for the PNG file.  If you
+ * use your own read or write routines, you can call either png_set_read_fn()
+ * or png_set_write_fn() instead of png_init_io().  If you have defined
+ * PNG_NO_STDIO, you must use a function of your own because "FILE *" isn't
+ * necessarily available.
+ */
+void PNGAPI
+png_init_io(png_structp png_ptr, png_FILE_p fp)
+{
+   png_debug(1, "in png_init_io\n");
+   png_ptr->io_ptr = (png_voidp)fp;
+}
+#endif
+
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+/* Convert the supplied time into an RFC 1123 string suitable for use in
+ * a "Creation Time" or other text-based time string.
+ */
+png_charp PNGAPI
+png_convert_to_rfc1123(png_structp png_ptr, png_timep ptime)
+{
+   static PNG_CONST char short_months[12][4] =
+        {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
+         "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
+
+   if (png_ptr->time_buffer == NULL)
+   {
+      png_ptr->time_buffer = (png_charp)png_malloc(png_ptr, (png_uint_32)(29*
+         png_sizeof(char)));
+   }
+
+#if defined(_WIN32_WCE)
+   {
+      wchar_t time_buf[29];
+      wsprintf(time_buf, TEXT("%d %S %d %02d:%02d:%02d +0000"),
+          ptime->day % 32, short_months[(ptime->month - 1) % 12],
+        ptime->year, ptime->hour % 24, ptime->minute % 60,
+          ptime->second % 61);
+      WideCharToMultiByte(CP_ACP, 0, time_buf, -1, png_ptr->time_buffer, 29,
+          NULL, NULL);
+   }
+#else
+#ifdef USE_FAR_KEYWORD
+   {
+      char near_time_buf[29];
+      sprintf(near_time_buf, "%d %s %d %02d:%02d:%02d +0000",
+          ptime->day % 32, short_months[(ptime->month - 1) % 12],
+          ptime->year, ptime->hour % 24, ptime->minute % 60,
+          ptime->second % 61);
+      png_memcpy(png_ptr->time_buffer, near_time_buf,
+          29*png_sizeof(char));
+   }
+#else
+   sprintf(png_ptr->time_buffer, "%d %s %d %02d:%02d:%02d +0000",
+       ptime->day % 32, short_months[(ptime->month - 1) % 12],
+       ptime->year, ptime->hour % 24, ptime->minute % 60,
+       ptime->second % 61);
+#endif
+#endif /* _WIN32_WCE */
+   return ((png_charp)png_ptr->time_buffer);
+}
+#endif /* PNG_TIME_RFC1123_SUPPORTED */
+
+#if 0
+/* Signature string for a PNG file. */
+png_bytep PNGAPI
+png_sig_bytes(void)
+{
+   return ((png_bytep)"\211\120\116\107\015\012\032\012");
+}
+#endif
+
+png_charp PNGAPI
+png_get_copyright(png_structp png_ptr)
+{
+   if (&png_ptr != NULL)  /* silence compiler warning about unused png_ptr */
+   return ((png_charp) "\n libpng version 1.2.8 - December 3, 2004\n\
+   Copyright (c) 1998-2004 Glenn Randers-Pehrson\n\
+   Copyright (c) 1996-1997 Andreas Dilger\n\
+   Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.\n");
+   return ((png_charp) "");
+}
+
+/* The following return the library version as a short string in the
+ * format 1.0.0 through 99.99.99zz.  To get the version of *.h files
+ * used with your application, print out PNG_LIBPNG_VER_STRING, which
+ * is defined in png.h.
+ * Note: now there is no difference between png_get_libpng_ver() and
+ * png_get_header_ver().  Due to the version_nn_nn_nn typedef guard,
+ * it is guaranteed that png.c uses the correct version of png.h.
+ */
+png_charp PNGAPI
+png_get_libpng_ver(png_structp png_ptr)
+{
+   /* Version of *.c files used when building libpng */
+   if (&png_ptr != NULL)  /* silence compiler warning about unused png_ptr */
+      return ((png_charp) PNG_LIBPNG_VER_STRING);
+   return ((png_charp) "");
+}
+
+png_charp PNGAPI
+png_get_header_ver(png_structp png_ptr)
+{
+   /* Version of *.h files used when building libpng */
+   if (&png_ptr != NULL)  /* silence compiler warning about unused png_ptr */
+      return ((png_charp) PNG_LIBPNG_VER_STRING);
+   return ((png_charp) "");
+}
+
+png_charp PNGAPI
+png_get_header_version(png_structp png_ptr)
+{
+   /* Returns longer string containing both version and date */
+   if (&png_ptr != NULL)  /* silence compiler warning about unused png_ptr */
+      return ((png_charp) PNG_HEADER_VERSION_STRING);
+   return ((png_charp) "");
+}
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+int PNGAPI
+png_handle_as_unknown(png_structp png_ptr, png_bytep chunk_name)
+{
+   /* check chunk_name and return "keep" value if it's on the list, else 0 */
+   int i;
+   png_bytep p;
+   if((png_ptr == NULL && chunk_name == NULL) || png_ptr->num_chunk_list<=0)
+      return 0;
+   p=png_ptr->chunk_list+png_ptr->num_chunk_list*5-5;
+   for (i = png_ptr->num_chunk_list; i; i--, p-=5)
+      if (!png_memcmp(chunk_name, p, 4))
+        return ((int)*(p+4));
+   return 0;
+}
+#endif
+
+/* This function, added to libpng-1.0.6g, is untested. */
+int PNGAPI
+png_reset_zstream(png_structp png_ptr)
+{
+   return (inflateReset(&png_ptr->zstream));
+}
+
+/* This function was added to libpng-1.0.7 */
+png_uint_32 PNGAPI
+png_access_version_number(void)
+{
+   /* Version of *.c files used when building libpng */
+   return((png_uint_32) PNG_LIBPNG_VER);
+}
+
+
+#if !defined(PNG_1_0_X)
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+    /* GRR:  could add this:   && defined(PNG_MMX_CODE_SUPPORTED) */
+/* this INTERNAL function was added to libpng 1.2.0 */
+void /* PRIVATE */
+png_init_mmx_flags (png_structp png_ptr)
+{
+    png_ptr->mmx_rowbytes_threshold = 0;
+    png_ptr->mmx_bitdepth_threshold = 0;
+
+#  if (defined(PNG_USE_PNGVCRD) || defined(PNG_USE_PNGGCCRD))
+
+    png_ptr->asm_flags |= PNG_ASM_FLAG_MMX_SUPPORT_COMPILED;
+
+    if (png_mmx_support() > 0) {
+        png_ptr->asm_flags |= PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU
+#    ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
+                              | PNG_ASM_FLAG_MMX_READ_COMBINE_ROW
+#    endif
+#    ifdef PNG_HAVE_ASSEMBLER_READ_INTERLACE
+                              | PNG_ASM_FLAG_MMX_READ_INTERLACE
+#    endif
+#    ifndef PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+                              ;
+#    else
+                              | PNG_ASM_FLAG_MMX_READ_FILTER_SUB
+                              | PNG_ASM_FLAG_MMX_READ_FILTER_UP
+                              | PNG_ASM_FLAG_MMX_READ_FILTER_AVG
+                              | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ;
+
+        png_ptr->mmx_rowbytes_threshold = PNG_MMX_ROWBYTES_THRESHOLD_DEFAULT;
+        png_ptr->mmx_bitdepth_threshold = PNG_MMX_BITDEPTH_THRESHOLD_DEFAULT;
+#    endif
+    } else {
+        png_ptr->asm_flags &= ~( PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU
+                               | PNG_MMX_READ_FLAGS
+                               | PNG_MMX_WRITE_FLAGS );
+    }
+
+#  else /* !((PNGVCRD || PNGGCCRD) && PNG_ASSEMBLER_CODE_SUPPORTED)) */
+
+    /* clear all MMX flags; no support is compiled in */
+    png_ptr->asm_flags &= ~( PNG_MMX_FLAGS );
+
+#  endif /* ?(PNGVCRD || PNGGCCRD) */
+}
+
+#endif /* !(PNG_ASSEMBLER_CODE_SUPPORTED) */
+
+/* this function was added to libpng 1.2.0 */
+#if !defined(PNG_USE_PNGGCCRD) && \
+    !(defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_USE_PNGVCRD))
+int PNGAPI
+png_mmx_support(void)
+{
+    return -1;
+}
+#endif
+#endif /* PNG_1_0_X */
+
+#ifdef PNG_SIZE_T
+/* Added at libpng version 1.2.6 */
+   PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size));
+png_size_t PNGAPI
+png_convert_size(size_t size)
+{
+  if (size > (png_size_t)-1)
+     PNG_ABORT();  /* We haven't got access to png_ptr, so no png_error() */
+  return ((png_size_t)size);
+}
+#endif /* PNG_SIZE_T */
diff --git a/gs/libpng/png.h b/gs/libpng/png.h
new file mode 100644
index 000000000..e87a3011c
--- /dev/null
+++ b/gs/libpng/png.h
@@ -0,0 +1,3419 @@
+/* png.h - header file for PNG reference library
+ *
+ * libpng version 1.2.8 - December 3, 2004
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * Authors and maintainers:
+ *  libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
+ *  libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
+ *  libpng versions 0.97, January 1998, through 1.2.8 - December 3, 2004: Glenn
+ *  See also "Contributing Authors", below.
+ *
+ * Note about libpng version numbers:
+ *
+ *    Due to various miscommunications, unforeseen code incompatibilities
+ *    and occasional factors outside the authors' control, version numbering
+ *    on the library has not always been consistent and straightforward.
+ *    The following table summarizes matters since version 0.89c, which was
+ *    the first widely used release:
+ *
+ *    source                 png.h  png.h  shared-lib
+ *    version                string   int  version
+ *    -------                ------ -----  ----------
+ *    0.89c "1.0 beta 3"     0.89      89  1.0.89
+ *    0.90  "1.0 beta 4"     0.90      90  0.90  [should have been 2.0.90]
+ *    0.95  "1.0 beta 5"     0.95      95  0.95  [should have been 2.0.95]
+ *    0.96  "1.0 beta 6"     0.96      96  0.96  [should have been 2.0.96]
+ *    0.97b "1.00.97 beta 7" 1.00.97   97  1.0.1 [should have been 2.0.97]
+ *    0.97c                  0.97      97  2.0.97
+ *    0.98                   0.98      98  2.0.98
+ *    0.99                   0.99      98  2.0.99
+ *    0.99a-m                0.99      99  2.0.99
+ *    1.00                   1.00     100  2.1.0 [100 should be 10000]
+ *    1.0.0      (from here on, the   100  2.1.0 [100 should be 10000]
+ *    1.0.1       png.h string is   10001  2.1.0
+ *    1.0.1a-e    identical to the  10002  from here on, the shared library
+ *    1.0.2       source version)   10002  is 2.V where V is the source code
+ *    1.0.2a-b                      10003  version, except as noted.
+ *    1.0.3                         10003
+ *    1.0.3a-d                      10004
+ *    1.0.4                         10004
+ *    1.0.4a-f                      10005
+ *    1.0.5 (+ 2 patches)           10005
+ *    1.0.5a-d                      10006
+ *    1.0.5e-r                      10100 (not source compatible)
+ *    1.0.5s-v                      10006 (not binary compatible)
+ *    1.0.6 (+ 3 patches)           10006 (still binary incompatible)
+ *    1.0.6d-f                      10007 (still binary incompatible)
+ *    1.0.6g                        10007
+ *    1.0.6h                        10007  10.6h (testing xy.z so-numbering)
+ *    1.0.6i                        10007  10.6i
+ *    1.0.6j                        10007  2.1.0.6j (incompatible with 1.0.0)
+ *    1.0.7beta11-14        DLLNUM  10007  2.1.0.7beta11-14 (binary compatible)
+ *    1.0.7beta15-18           1    10007  2.1.0.7beta15-18 (binary compatible)
+ *    1.0.7rc1-2               1    10007  2.1.0.7rc1-2 (binary compatible)
+ *    1.0.7                    1    10007  (still compatible)
+ *    1.0.8beta1-4             1    10008  2.1.0.8beta1-4
+ *    1.0.8rc1                 1    10008  2.1.0.8rc1
+ *    1.0.8                    1    10008  2.1.0.8
+ *    1.0.9beta1-6             1    10009  2.1.0.9beta1-6
+ *    1.0.9rc1                 1    10009  2.1.0.9rc1
+ *    1.0.9beta7-10            1    10009  2.1.0.9beta7-10
+ *    1.0.9rc2                 1    10009  2.1.0.9rc2
+ *    1.0.9                    1    10009  2.1.0.9
+ *    1.0.10beta1              1    10010  2.1.0.10beta1
+ *    1.0.10rc1                1    10010  2.1.0.10rc1
+ *    1.0.10                   1    10010  2.1.0.10
+ *    1.0.11beta1-3            1    10011  2.1.0.11beta1-3
+ *    1.0.11rc1                1    10011  2.1.0.11rc1
+ *    1.0.11                   1    10011  2.1.0.11
+ *    1.0.12beta1-2            2    10012  2.1.0.12beta1-2
+ *    1.0.12rc1                2    10012  2.1.0.12rc1
+ *    1.0.12                   2    10012  2.1.0.12
+ *    1.1.0a-f                 -    10100  2.1.1.0a-f (branch abandoned)
+ *    1.2.0beta1-2             2    10200  2.1.2.0beta1-2
+ *    1.2.0beta3-5             3    10200  3.1.2.0beta3-5
+ *    1.2.0rc1                 3    10200  3.1.2.0rc1
+ *    1.2.0                    3    10200  3.1.2.0
+ *    1.2.1beta1-4             3    10201  3.1.2.1beta1-4
+ *    1.2.1rc1-2               3    10201  3.1.2.1rc1-2
+ *    1.2.1                    3    10201  3.1.2.1
+ *    1.2.2beta1-6            12    10202  12.so.0.1.2.2beta1-6
+ *    1.0.13beta1             10    10013  10.so.0.1.0.13beta1
+ *    1.0.13rc1               10    10013  10.so.0.1.0.13rc1
+ *    1.2.2rc1                12    10202  12.so.0.1.2.2rc1
+ *    1.0.13                  10    10013  10.so.0.1.0.13
+ *    1.2.2                   12    10202  12.so.0.1.2.2
+ *    1.2.3rc1-6              12    10203  12.so.0.1.2.3rc1-6
+ *    1.2.3                   12    10203  12.so.0.1.2.3
+ *    1.2.4beta1-3            13    10204  12.so.0.1.2.4beta1-3
+ *    1.0.14rc1               13    10014  10.so.0.1.0.14rc1
+ *    1.2.4rc1                13    10204  12.so.0.1.2.4rc1
+ *    1.0.14                  10    10014  10.so.0.1.0.14
+ *    1.2.4                   13    10204  12.so.0.1.2.4
+ *    1.2.5beta1-2            13    10205  12.so.0.1.2.5beta1-2
+ *    1.0.15rc1-3             10    10015  10.so.0.1.0.15rc1-3
+ *    1.2.5rc1-3              13    10205  12.so.0.1.2.5rc1-3
+ *    1.0.15                  10    10015  10.so.0.1.0.15
+ *    1.2.5                   13    10205  12.so.0.1.2.5
+ *    1.2.6beta1-4            13    10206  12.so.0.1.2.6beta1-4
+ *    1.0.16                  10    10016  10.so.0.1.0.16
+ *    1.2.6                   13    10206  12.so.0.1.2.6
+ *    1.2.7beta1-2            13    10207  12.so.0.1.2.7beta1-2
+ *    1.0.17rc1               10    10017  12.so.0.1.0.17rc1
+ *    1.2.7rc1                13    10207  12.so.0.1.2.7rc1
+ *    1.0.17                  10    10017  12.so.0.1.0.17
+ *    1.2.7                   13    10207  12.so.0.1.2.7
+ *    1.2.8beta1-5            13    10208  12.so.0.1.2.8beta1-5
+ *    1.0.18rc1-5             10    10018  12.so.0.1.0.18rc1-5
+ *    1.2.8rc1-5              13    10208  12.so.0.1.2.8rc1-5
+ *    1.0.18                  10    10018  12.so.0.1.0.18
+ *    1.2.8                   13    10208  12.so.0.1.2.8
+ *
+ *    Henceforth the source version will match the shared-library major
+ *    and minor numbers; the shared-library major version number will be
+ *    used for changes in backward compatibility, as it is intended.  The
+ *    PNG_LIBPNG_VER macro, which is not used within libpng but is available
+ *    for applications, is an unsigned integer of the form xyyzz corresponding
+ *    to the source version x.y.z (leading zeros in y and z).  Beta versions
+ *    were given the previous public release number plus a letter, until
+ *    version 1.0.6j; from then on they were given the upcoming public
+ *    release number plus "betaNN" or "rcN".
+ *
+ *    Binary incompatibility exists only when applications make direct access
+ *    to the info_ptr or png_ptr members through png.h, and the compiled
+ *    application is loaded with a different version of the library.
+ *
+ *    DLLNUM will change each time there are forward or backward changes
+ *    in binary compatibility (e.g., when a new feature is added).
+ *
+ * See libpng.txt or libpng.3 for more information.  The PNG specification
+ * is available as a W3C Recommendation and as an ISO Specification,
+ * <http://www.w3.org/TR/2003/REC-PNG-20031110/
+ */
+
+/*
+ * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
+ *
+ * If you modify libpng you may insert additional notices immediately following
+ * this sentence.
+ *
+ * libpng versions 1.2.6, August 15, 2004, through 1.2.8, December 3, 2004, are
+ * Copyright (c) 2004 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-1.2.5
+ * with the following individual added to the list of Contributing Authors:
+ *
+ *    Cosmin Truta
+ *
+ * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
+ * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-1.0.6
+ * with the following individuals added to the list of Contributing Authors:
+ *
+ *    Simon-Pierre Cadieux
+ *    Eric S. Raymond
+ *    Gilles Vollant
+ *
+ * and with the following additions to the disclaimer:
+ *
+ *    There is no warranty against interference with your enjoyment of the
+ *    library or against infringement.  There is no warranty that our
+ *    efforts or the library will fulfill any of your particular purposes
+ *    or needs.  This library is provided with all faults, and the entire
+ *    risk of satisfactory quality, performance, accuracy, and effort is with
+ *    the user.
+ *
+ * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
+ * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-0.96,
+ * with the following individuals added to the list of Contributing Authors:
+ *
+ *    Tom Lane
+ *    Glenn Randers-Pehrson
+ *    Willem van Schaik
+ *
+ * libpng versions 0.89, June 1996, through 0.96, May 1997, are
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Distributed according to the same disclaimer and license as libpng-0.88,
+ * with the following individuals added to the list of Contributing Authors:
+ *
+ *    John Bowler
+ *    Kevin Bracey
+ *    Sam Bushell
+ *    Magnus Holmgren
+ *    Greg Roelofs
+ *    Tom Tanner
+ *
+ * libpng versions 0.5, May 1995, through 0.88, January 1996, are
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ *
+ * For the purposes of this copyright and license, "Contributing Authors"
+ * is defined as the following set of individuals:
+ *
+ *    Andreas Dilger
+ *    Dave Martindale
+ *    Guy Eric Schalnat
+ *    Paul Schmidt
+ *    Tim Wegner
+ *
+ * The PNG Reference Library is supplied "AS IS".  The Contributing Authors
+ * and Group 42, Inc. disclaim all warranties, expressed or implied,
+ * including, without limitation, the warranties of merchantability and of
+ * fitness for any purpose.  The Contributing Authors and Group 42, Inc.
+ * assume no liability for direct, indirect, incidental, special, exemplary,
+ * or consequential damages, which may result from the use of the PNG
+ * Reference Library, even if advised of the possibility of such damage.
+ *
+ * Permission is hereby granted to use, copy, modify, and distribute this
+ * source code, or portions hereof, for any purpose, without fee, subject
+ * to the following restrictions:
+ *
+ * 1. The origin of this source code must not be misrepresented.
+ *
+ * 2. Altered versions must be plainly marked as such and
+ * must not be misrepresented as being the original source.
+ *
+ * 3. This Copyright notice may not be removed or altered from
+ *    any source or altered source distribution.
+ *
+ * The Contributing Authors and Group 42, Inc. specifically permit, without
+ * fee, and encourage the use of this source code as a component to
+ * supporting the PNG file format in commercial products.  If you use this
+ * source code in a product, acknowledgment is not required but would be
+ * appreciated.
+ */
+
+/*
+ * A "png_get_copyright" function is available, for convenient use in "about"
+ * boxes and the like:
+ *
+ * printf("%s",png_get_copyright(NULL));
+ *
+ * Also, the PNG logo (in PNG format, of course) is supplied in the
+ * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
+ */
+
+/*
+ * Libpng is OSI Certified Open Source Software.  OSI Certified is a
+ * certification mark of the Open Source Initiative.
+ */
+
+/*
+ * The contributing authors would like to thank all those who helped
+ * with testing, bug fixes, and patience.  This wouldn't have been
+ * possible without all of you.
+ *
+ * Thanks to Frank J. T. Wojcik for helping with the documentation.
+ */
+
+/*
+ * Y2K compliance in libpng:
+ * =========================
+ *
+ *    December 3, 2004
+ *
+ *    Since the PNG Development group is an ad-hoc body, we can't make
+ *    an official declaration.
+ *
+ *    This is your unofficial assurance that libpng from version 0.71 and
+ *    upward through 1.2.8 are Y2K compliant.  It is my belief that earlier
+ *    versions were also Y2K compliant.
+ *
+ *    Libpng only has three year fields.  One is a 2-byte unsigned integer
+ *    that will hold years up to 65535.  The other two hold the date in text
+ *    format, and will hold years up to 9999.
+ *
+ *    The integer is
+ *        "png_uint_16 year" in png_time_struct.
+ *
+ *    The strings are
+ *        "png_charp time_buffer" in png_struct and
+ *        "near_time_buffer", which is a local character string in png.c.
+ *
+ *    There are seven time-related functions:
+ *        png.c: png_convert_to_rfc_1123() in png.c
+ *          (formerly png_convert_to_rfc_1152() in error)
+ *        png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
+ *        png_convert_from_time_t() in pngwrite.c
+ *        png_get_tIME() in pngget.c
+ *        png_handle_tIME() in pngrutil.c, called in pngread.c
+ *        png_set_tIME() in pngset.c
+ *        png_write_tIME() in pngwutil.c, called in pngwrite.c
+ *
+ *    All handle dates properly in a Y2K environment.  The
+ *    png_convert_from_time_t() function calls gmtime() to convert from system
+ *    clock time, which returns (year - 1900), which we properly convert to
+ *    the full 4-digit year.  There is a possibility that applications using
+ *    libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
+ *    function, or that they are incorrectly passing only a 2-digit year
+ *    instead of "year - 1900" into the png_convert_from_struct_tm() function,
+ *    but this is not under our control.  The libpng documentation has always
+ *    stated that it works with 4-digit years, and the APIs have been
+ *    documented as such.
+ *
+ *    The tIME chunk itself is also Y2K compliant.  It uses a 2-byte unsigned
+ *    integer to hold the year, and can hold years as large as 65535.
+ *
+ *    zlib, upon which libpng depends, is also Y2K compliant.  It contains
+ *    no date-related code.
+ *
+ *       Glenn Randers-Pehrson
+ *       libpng maintainer
+ *       PNG Development Group
+ */
+
+#ifndef PNG_H
+#define PNG_H
+
+/* This is not the place to learn how to use libpng.  The file libpng.txt
+ * describes how to use libpng, and the file example.c summarizes it
+ * with some code on which to build.  This file is useful for looking
+ * at the actual function definitions and structure components.
+ */
+
+/* Version information for png.h - this should match the version in png.c */
+#define PNG_LIBPNG_VER_STRING "1.2.8"
+#define PNG_HEADER_VERSION_STRING \
+   " libpng version 1.2.8 - December 3, 2004 (header)\n"
+
+#define PNG_LIBPNG_VER_SONUM   0
+#define PNG_LIBPNG_VER_DLLNUM  13
+
+/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
+#define PNG_LIBPNG_VER_MAJOR   1
+#define PNG_LIBPNG_VER_MINOR   2
+#define PNG_LIBPNG_VER_RELEASE 8
+/* This should match the numeric part of the final component of
+ * PNG_LIBPNG_VER_STRING, omitting any leading zero: */
+
+#define PNG_LIBPNG_VER_BUILD  0
+
+/* Release Status */
+#define PNG_LIBPNG_BUILD_ALPHA    1
+#define PNG_LIBPNG_BUILD_BETA     2
+#define PNG_LIBPNG_BUILD_RC       3
+#define PNG_LIBPNG_BUILD_STABLE   4
+#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
+  
+/* Release-Specific Flags */
+#define PNG_LIBPNG_BUILD_PATCH    8 /* Can be OR'ed with
+                                       PNG_LIBPNG_BUILD_STABLE only */
+#define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with
+                                       PNG_LIBPNG_BUILD_SPECIAL */
+#define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
+                                       PNG_LIBPNG_BUILD_PRIVATE */
+
+#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
+
+/* Careful here.  At one time, Guy wanted to use 082, but that would be octal.
+ * We must not include leading zeros.
+ * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
+ * version 1.0.0 was mis-numbered 100 instead of 10000).  From
+ * version 1.0.1 it's    xxyyzz, where x=major, y=minor, z=release */
+#define PNG_LIBPNG_VER 10208 /* 1.2.8 */
+
+#ifndef PNG_VERSION_INFO_ONLY
+/* include the compression library's header */
+#include "zlib.h"
+#endif
+
+/* include all user configurable info, including optional assembler routines */
+#include "pngconf.h"
+
+/*
+ * Added at libpng-1.2.8 */
+/* Ref MSDN: Private as priority over Special
+ * VS_FF_PRIVATEBUILD File *was not* built using standard release
+ * procedures. If this value is given, the StringFileInfo block must
+ * contain a PrivateBuild string. 
+ *
+ * VS_FF_SPECIALBUILD File *was* built by the original company using
+ * standard release procedures but is a variation of the standard
+ * file of the same version number. If this value is given, the
+ * StringFileInfo block must contain a SpecialBuild string. 
+ */
+
+#if defined(PNG_USER_PRIVATEBUILD)
+#  define PNG_LIBPNG_BUILD_TYPE PNG_LIBPNG_BUILD_BASE_TYPE | \
+          PNG_LIBPNG_BUILD_PRIVATE
+#else
+#  if defined(PNG_LIBPNG_SPECIALBUILD)
+#    define PNG_LIBPNG_BUILD_TYPE PNG_LIBPNG_BUILD_BASE_TYPE | \
+            PNG_LIBPNG_BUILD_SPECIAL
+#  else
+#    define PNG_LIBPNG_BUILD_TYPE PNG_LIBPNG_BUILD_BASE_TYPE
+#  endif
+#endif
+
+#ifndef PNG_VERSION_INFO_ONLY
+
+/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/* This file is arranged in several sections.  The first section contains
+ * structure and type definitions.  The second section contains the external
+ * library functions, while the third has the internal library functions,
+ * which applications aren't expected to use directly.
+ */
+
+#ifndef PNG_NO_TYPECAST_NULL
+#define int_p_NULL                (int *)NULL
+#define png_bytep_NULL            (png_bytep)NULL
+#define png_bytepp_NULL           (png_bytepp)NULL
+#define png_doublep_NULL          (png_doublep)NULL
+#define png_error_ptr_NULL        (png_error_ptr)NULL
+#define png_flush_ptr_NULL        (png_flush_ptr)NULL
+#define png_free_ptr_NULL         (png_free_ptr)NULL
+#define png_infopp_NULL           (png_infopp)NULL
+#define png_malloc_ptr_NULL       (png_malloc_ptr)NULL
+#define png_read_status_ptr_NULL  (png_read_status_ptr)NULL
+#define png_rw_ptr_NULL           (png_rw_ptr)NULL
+#define png_structp_NULL          (png_structp)NULL
+#define png_uint_16p_NULL         (png_uint_16p)NULL
+#define png_voidp_NULL            (png_voidp)NULL
+#define png_write_status_ptr_NULL (png_write_status_ptr)NULL
+#else
+#define int_p_NULL                NULL
+#define png_bytep_NULL            NULL
+#define png_bytepp_NULL           NULL
+#define png_doublep_NULL          NULL
+#define png_error_ptr_NULL        NULL
+#define png_flush_ptr_NULL        NULL
+#define png_free_ptr_NULL         NULL
+#define png_infopp_NULL           NULL
+#define png_malloc_ptr_NULL       NULL
+#define png_read_status_ptr_NULL  NULL
+#define png_rw_ptr_NULL           NULL
+#define png_structp_NULL          NULL
+#define png_uint_16p_NULL         NULL
+#define png_voidp_NULL            NULL
+#define png_write_status_ptr_NULL NULL
+#endif
+
+/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
+#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
+/* Version information for C files, stored in png.c.  This had better match
+ * the version above.
+ */
+#ifdef PNG_USE_GLOBAL_ARRAYS
+PNG_EXPORT_VAR (const char) png_libpng_ver[18];
+  /* need room for 99.99.99beta99z */
+#else
+#define png_libpng_ver png_get_header_ver(NULL)
+#endif
+
+#ifdef PNG_USE_GLOBAL_ARRAYS
+/* This was removed in version 1.0.5c */
+/* Structures to facilitate easy interlacing.  See png.c for more details */
+PNG_EXPORT_VAR (const int FARDATA) png_pass_start[7];
+PNG_EXPORT_VAR (const int FARDATA) png_pass_inc[7];
+PNG_EXPORT_VAR (const int FARDATA) png_pass_ystart[7];
+PNG_EXPORT_VAR (const int FARDATA) png_pass_yinc[7];
+PNG_EXPORT_VAR (const int FARDATA) png_pass_mask[7];
+PNG_EXPORT_VAR (const int FARDATA) png_pass_dsp_mask[7];
+#ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
+PNG_EXPORT_VAR (const int FARDATA) png_pass_width[7];
+#endif
+/* This isn't currently used.  If you need it, see png.c for more details.
+PNG_EXPORT_VAR (const int FARDATA) png_pass_height[7];
+*/
+#endif
+
+#endif /* PNG_NO_EXTERN */
+
+/* Three color definitions.  The order of the red, green, and blue, (and the
+ * exact size) is not important, although the size of the fields need to
+ * be png_byte or png_uint_16 (as defined below).
+ */
+typedef struct png_color_struct
+{
+   png_byte red;
+   png_byte green;
+   png_byte blue;
+} png_color;
+typedef png_color FAR * png_colorp;
+typedef png_color FAR * FAR * png_colorpp;
+
+typedef struct png_color_16_struct
+{
+   png_byte index;    /* used for palette files */
+   png_uint_16 red;   /* for use in red green blue files */
+   png_uint_16 green;
+   png_uint_16 blue;
+   png_uint_16 gray;  /* for use in grayscale files */
+} png_color_16;
+typedef png_color_16 FAR * png_color_16p;
+typedef png_color_16 FAR * FAR * png_color_16pp;
+
+typedef struct png_color_8_struct
+{
+   png_byte red;   /* for use in red green blue files */
+   png_byte green;
+   png_byte blue;
+   png_byte gray;  /* for use in grayscale files */
+   png_byte alpha; /* for alpha channel files */
+} png_color_8;
+typedef png_color_8 FAR * png_color_8p;
+typedef png_color_8 FAR * FAR * png_color_8pp;
+
+/*
+ * The following two structures are used for the in-core representation
+ * of sPLT chunks.
+ */
+typedef struct png_sPLT_entry_struct
+{
+   png_uint_16 red;
+   png_uint_16 green;
+   png_uint_16 blue;
+   png_uint_16 alpha;
+   png_uint_16 frequency;
+} png_sPLT_entry;
+typedef png_sPLT_entry FAR * png_sPLT_entryp;
+typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
+
+/*  When the depth of the sPLT palette is 8 bits, the color and alpha samples
+ *  occupy the LSB of their respective members, and the MSB of each member
+ *  is zero-filled.  The frequency member always occupies the full 16 bits.
+ */
+
+typedef struct png_sPLT_struct
+{
+   png_charp name;           /* palette name */
+   png_byte depth;           /* depth of palette samples */
+   png_sPLT_entryp entries;  /* palette entries */
+   png_int_32 nentries;      /* number of palette entries */
+} png_sPLT_t;
+typedef png_sPLT_t FAR * png_sPLT_tp;
+typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
+
+#ifdef PNG_TEXT_SUPPORTED
+/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
+ * and whether that contents is compressed or not.  The "key" field
+ * points to a regular zero-terminated C string.  The "text", "lang", and
+ * "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
+ * However, the * structure returned by png_get_text() will always contain
+ * regular zero-terminated C strings (possibly empty), never NULL pointers,
+ * so they can be safely used in printf() and other string-handling functions.
+ */
+typedef struct png_text_struct
+{
+   int  compression;       /* compression value:
+                             -1: tEXt, none
+                              0: zTXt, deflate
+                              1: iTXt, none
+                              2: iTXt, deflate  */
+   png_charp key;          /* keyword, 1-79 character description of "text" */
+   png_charp text;         /* comment, may be an empty string (ie "")
+                              or a NULL pointer */
+   png_size_t text_length; /* length of the text string */
+#ifdef PNG_iTXt_SUPPORTED
+   png_size_t itxt_length; /* length of the itxt string */
+   png_charp lang;         /* language code, 0-79 characters
+                              or a NULL pointer */
+   png_charp lang_key;     /* keyword translated UTF-8 string, 0 or more
+                              chars or a NULL pointer */
+#endif
+} png_text;
+typedef png_text FAR * png_textp;
+typedef png_text FAR * FAR * png_textpp;
+#endif
+
+/* Supported compression types for text in PNG files (tEXt, and zTXt).
+ * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
+#define PNG_TEXT_COMPRESSION_NONE_WR -3
+#define PNG_TEXT_COMPRESSION_zTXt_WR -2
+#define PNG_TEXT_COMPRESSION_NONE    -1
+#define PNG_TEXT_COMPRESSION_zTXt     0
+#define PNG_ITXT_COMPRESSION_NONE     1
+#define PNG_ITXT_COMPRESSION_zTXt     2
+#define PNG_TEXT_COMPRESSION_LAST     3  /* Not a valid value */
+
+/* png_time is a way to hold the time in an machine independent way.
+ * Two conversions are provided, both from time_t and struct tm.  There
+ * is no portable way to convert to either of these structures, as far
+ * as I know.  If you know of a portable way, send it to me.  As a side
+ * note - PNG has always been Year 2000 compliant!
+ */
+typedef struct png_time_struct
+{
+   png_uint_16 year; /* full year, as in, 1995 */
+   png_byte month;   /* month of year, 1 - 12 */
+   png_byte day;     /* day of month, 1 - 31 */
+   png_byte hour;    /* hour of day, 0 - 23 */
+   png_byte minute;  /* minute of hour, 0 - 59 */
+   png_byte second;  /* second of minute, 0 - 60 (for leap seconds) */
+} png_time;
+typedef png_time FAR * png_timep;
+typedef png_time FAR * FAR * png_timepp;
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+/* png_unknown_chunk is a structure to hold queued chunks for which there is
+ * no specific support.  The idea is that we can use this to queue
+ * up private chunks for output even though the library doesn't actually
+ * know about their semantics.
+ */
+typedef struct png_unknown_chunk_t
+{
+    png_byte name[5];
+    png_byte *data;
+    png_size_t size;
+
+    /* libpng-using applications should NOT directly modify this byte. */
+    png_byte location; /* mode of operation at read time */
+}
+png_unknown_chunk;
+typedef png_unknown_chunk FAR * png_unknown_chunkp;
+typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
+#endif
+
+/* png_info is a structure that holds the information in a PNG file so
+ * that the application can find out the characteristics of the image.
+ * If you are reading the file, this structure will tell you what is
+ * in the PNG file.  If you are writing the file, fill in the information
+ * you want to put into the PNG file, then call png_write_info().
+ * The names chosen should be very close to the PNG specification, so
+ * consult that document for information about the meaning of each field.
+ *
+ * With libpng < 0.95, it was only possible to directly set and read the
+ * the values in the png_info_struct, which meant that the contents and
+ * order of the values had to remain fixed.  With libpng 0.95 and later,
+ * however, there are now functions that abstract the contents of
+ * png_info_struct from the application, so this makes it easier to use
+ * libpng with dynamic libraries, and even makes it possible to use
+ * libraries that don't have all of the libpng ancillary chunk-handing
+ * functionality.
+ *
+ * In any case, the order of the parameters in png_info_struct should NOT
+ * be changed for as long as possible to keep compatibility with applications
+ * that use the old direct-access method with png_info_struct.
+ *
+ * The following members may have allocated storage attached that should be
+ * cleaned up before the structure is discarded: palette, trans, text,
+ * pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile,
+ * splt_palettes, scal_unit, row_pointers, and unknowns.   By default, these
+ * are automatically freed when the info structure is deallocated, if they were
+ * allocated internally by libpng.  This behavior can be changed by means
+ * of the png_data_freer() function.
+ *
+ * More allocation details: all the chunk-reading functions that
+ * change these members go through the corresponding png_set_*
+ * functions.  A function to clear these members is available: see
+ * png_free_data().  The png_set_* functions do not depend on being
+ * able to point info structure members to any of the storage they are
+ * passed (they make their own copies), EXCEPT that the png_set_text
+ * functions use the same storage passed to them in the text_ptr or
+ * itxt_ptr structure argument, and the png_set_rows and png_set_unknowns
+ * functions do not make their own copies.
+ */
+typedef struct png_info_struct
+{
+   /* the following are necessary for every PNG file */
+   png_uint_32 width;       /* width of image in pixels (from IHDR) */
+   png_uint_32 height;      /* height of image in pixels (from IHDR) */
+   png_uint_32 valid;       /* valid chunk data (see PNG_INFO_ below) */
+   png_uint_32 rowbytes;    /* bytes needed to hold an untransformed row */
+   png_colorp palette;      /* array of color values (valid & PNG_INFO_PLTE) */
+   png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
+   png_uint_16 num_trans;   /* number of transparent palette color (tRNS) */
+   png_byte bit_depth;      /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
+   png_byte color_type;     /* see PNG_COLOR_TYPE_ below (from IHDR) */
+   /* The following three should have been named *_method not *_type */
+   png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
+   png_byte filter_type;    /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
+   png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
+
+   /* The following is informational only on read, and not used on writes. */
+   png_byte channels;       /* number of data channels per pixel (1, 2, 3, 4) */
+   png_byte pixel_depth;    /* number of bits per pixel */
+   png_byte spare_byte;     /* to align the data, and for future use */
+   png_byte signature[8];   /* magic bytes read by libpng from start of file */
+
+   /* The rest of the data is optional.  If you are reading, check the
+    * valid field to see if the information in these are valid.  If you
+    * are writing, set the valid field to those chunks you want written,
+    * and initialize the appropriate fields below.
+    */
+
+#if defined(PNG_gAMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
+   /* The gAMA chunk describes the gamma characteristics of the system
+    * on which the image was created, normally in the range [1.0, 2.5].
+    * Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
+    */
+   float gamma; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
+#endif
+
+#if defined(PNG_sRGB_SUPPORTED)
+    /* GR-P, 0.96a */
+    /* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
+   png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
+#endif
+
+#if defined(PNG_TEXT_SUPPORTED)
+   /* The tEXt, and zTXt chunks contain human-readable textual data in
+    * uncompressed, compressed, and optionally compressed forms, respectively.
+    * The data in "text" is an array of pointers to uncompressed,
+    * null-terminated C strings. Each chunk has a keyword that describes the
+    * textual data contained in that chunk.  Keywords are not required to be
+    * unique, and the text string may be empty.  Any number of text chunks may
+    * be in an image.
+    */
+   int num_text; /* number of comments read/to write */
+   int max_text; /* current size of text array */
+   png_textp text; /* array of comments read/to write */
+#endif /* PNG_TEXT_SUPPORTED */
+
+#if defined(PNG_tIME_SUPPORTED)
+   /* The tIME chunk holds the last time the displayed image data was
+    * modified.  See the png_time struct for the contents of this struct.
+    */
+   png_time mod_time;
+#endif
+
+#if defined(PNG_sBIT_SUPPORTED)
+   /* The sBIT chunk specifies the number of significant high-order bits
+    * in the pixel data.  Values are in the range [1, bit_depth], and are
+    * only specified for the channels in the pixel data.  The contents of
+    * the low-order bits is not specified.  Data is valid if
+    * (valid & PNG_INFO_sBIT) is non-zero.
+    */
+   png_color_8 sig_bit; /* significant bits in color channels */
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_EXPAND_SUPPORTED) || \
+defined(PNG_READ_BACKGROUND_SUPPORTED)
+   /* The tRNS chunk supplies transparency data for paletted images and
+    * other image types that don't need a full alpha channel.  There are
+    * "num_trans" transparency values for a paletted image, stored in the
+    * same order as the palette colors, starting from index 0.  Values
+    * for the data are in the range [0, 255], ranging from fully transparent
+    * to fully opaque, respectively.  For non-paletted images, there is a
+    * single color specified that should be treated as fully transparent.
+    * Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
+    */
+   png_bytep trans; /* transparent values for paletted image */
+   png_color_16 trans_values; /* transparent color for non-palette image */
+#endif
+
+#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+   /* The bKGD chunk gives the suggested image background color if the
+    * display program does not have its own background color and the image
+    * is needs to composited onto a background before display.  The colors
+    * in "background" are normally in the same color space/depth as the
+    * pixel data.  Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
+    */
+   png_color_16 background;
+#endif
+
+#if defined(PNG_oFFs_SUPPORTED)
+   /* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
+    * and downwards from the top-left corner of the display, page, or other
+    * application-specific co-ordinate space.  See the PNG_OFFSET_ defines
+    * below for the unit types.  Valid if (valid & PNG_INFO_oFFs) non-zero.
+    */
+   png_int_32 x_offset; /* x offset on page */
+   png_int_32 y_offset; /* y offset on page */
+   png_byte offset_unit_type; /* offset units type */
+#endif
+
+#if defined(PNG_pHYs_SUPPORTED)
+   /* The pHYs chunk gives the physical pixel density of the image for
+    * display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
+    * defines below).  Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
+    */
+   png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
+   png_uint_32 y_pixels_per_unit; /* vertical pixel density */
+   png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+   /* The hIST chunk contains the relative frequency or importance of the
+    * various palette entries, so that a viewer can intelligently select a
+    * reduced-color palette, if required.  Data is an array of "num_palette"
+    * values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
+    * is non-zero.
+    */
+   png_uint_16p hist;
+#endif
+
+#ifdef PNG_cHRM_SUPPORTED
+   /* The cHRM chunk describes the CIE color characteristics of the monitor
+    * on which the PNG was created.  This data allows the viewer to do gamut
+    * mapping of the input image to ensure that the viewer sees the same
+    * colors in the image as the creator.  Values are in the range
+    * [0.0, 0.8].  Data valid if (valid & PNG_INFO_cHRM) non-zero.
+    */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   float x_white;
+   float y_white;
+   float x_red;
+   float y_red;
+   float x_green;
+   float y_green;
+   float x_blue;
+   float y_blue;
+#endif
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+   /* The pCAL chunk describes a transformation between the stored pixel
+    * values and original physical data values used to create the image.
+    * The integer range [0, 2^bit_depth - 1] maps to the floating-point
+    * range given by [pcal_X0, pcal_X1], and are further transformed by a
+    * (possibly non-linear) transformation function given by "pcal_type"
+    * and "pcal_params" into "pcal_units".  Please see the PNG_EQUATION_
+    * defines below, and the PNG-Group's PNG extensions document for a
+    * complete description of the transformations and how they should be
+    * implemented, and for a description of the ASCII parameter strings.
+    * Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
+    */
+   png_charp pcal_purpose;  /* pCAL chunk description string */
+   png_int_32 pcal_X0;      /* minimum value */
+   png_int_32 pcal_X1;      /* maximum value */
+   png_charp pcal_units;    /* Latin-1 string giving physical units */
+   png_charpp pcal_params;  /* ASCII strings containing parameter values */
+   png_byte pcal_type;      /* equation type (see PNG_EQUATION_ below) */
+   png_byte pcal_nparams;   /* number of parameters given in pcal_params */
+#endif
+
+/* New members added in libpng-1.0.6 */
+#ifdef PNG_FREE_ME_SUPPORTED
+   png_uint_32 free_me;     /* flags items libpng is responsible for freeing */
+#endif
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+   /* storage for unknown chunks that the library doesn't recognize. */
+   png_unknown_chunkp unknown_chunks;
+   png_size_t unknown_chunks_num;
+#endif
+
+#if defined(PNG_iCCP_SUPPORTED)
+   /* iCCP chunk data. */
+   png_charp iccp_name;     /* profile name */
+   png_charp iccp_profile;  /* International Color Consortium profile data */
+                            /* Note to maintainer: should be png_bytep */
+   png_uint_32 iccp_proflen;  /* ICC profile data length */
+   png_byte iccp_compression; /* Always zero */
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+   /* data on sPLT chunks (there may be more than one). */
+   png_sPLT_tp splt_palettes;
+   png_uint_32 splt_palettes_num;
+#endif
+
+#if defined(PNG_sCAL_SUPPORTED)
+   /* The sCAL chunk describes the actual physical dimensions of the
+    * subject matter of the graphic.  The chunk contains a unit specification
+    * a byte value, and two ASCII strings representing floating-point
+    * values.  The values are width and height corresponsing to one pixel
+    * in the image.  This external representation is converted to double
+    * here.  Data values are valid if (valid & PNG_INFO_sCAL) is non-zero.
+    */
+   png_byte scal_unit;         /* unit of physical scale */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   double scal_pixel_width;    /* width of one pixel */
+   double scal_pixel_height;   /* height of one pixel */
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   png_charp scal_s_width;     /* string containing height */
+   png_charp scal_s_height;    /* string containing width */
+#endif
+#endif
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+   /* Memory has been allocated if (valid & PNG_ALLOCATED_INFO_ROWS) non-zero */
+   /* Data valid if (valid & PNG_INFO_IDAT) non-zero */
+   png_bytepp row_pointers;        /* the image bits */
+#endif
+
+#if defined(PNG_FIXED_POINT_SUPPORTED) && defined(PNG_gAMA_SUPPORTED)
+   png_fixed_point int_gamma; /* gamma of image, if (valid & PNG_INFO_gAMA) */
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED) && defined(PNG_FIXED_POINT_SUPPORTED)
+   png_fixed_point int_x_white;
+   png_fixed_point int_y_white;
+   png_fixed_point int_x_red;
+   png_fixed_point int_y_red;
+   png_fixed_point int_x_green;
+   png_fixed_point int_y_green;
+   png_fixed_point int_x_blue;
+   png_fixed_point int_y_blue;
+#endif
+
+} png_info;
+
+typedef png_info FAR * png_infop;
+typedef png_info FAR * FAR * png_infopp;
+
+/* Maximum positive integer used in PNG is (2^31)-1 */
+#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
+#define PNG_UINT_32_MAX ((png_uint_32)(-1))
+#define PNG_SIZE_MAX ((png_size_t)(-1))
+/* PNG_MAX_UINT is deprecated; use PNG_UINT_31_MAX instead. */
+#define PNG_MAX_UINT PNG_UINT_31_MAX
+
+/* These describe the color_type field in png_info. */
+/* color type masks */
+#define PNG_COLOR_MASK_PALETTE    1
+#define PNG_COLOR_MASK_COLOR      2
+#define PNG_COLOR_MASK_ALPHA      4
+
+/* color types.  Note that not all combinations are legal */
+#define PNG_COLOR_TYPE_GRAY 0
+#define PNG_COLOR_TYPE_PALETTE  (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
+#define PNG_COLOR_TYPE_RGB        (PNG_COLOR_MASK_COLOR)
+#define PNG_COLOR_TYPE_RGB_ALPHA  (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
+#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
+/* aliases */
+#define PNG_COLOR_TYPE_RGBA  PNG_COLOR_TYPE_RGB_ALPHA
+#define PNG_COLOR_TYPE_GA  PNG_COLOR_TYPE_GRAY_ALPHA
+
+/* This is for compression type. PNG 1.0-1.2 only define the single type. */
+#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
+#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
+
+/* This is for filter type. PNG 1.0-1.2 only define the single type. */
+#define PNG_FILTER_TYPE_BASE      0 /* Single row per-byte filtering */
+#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
+#define PNG_FILTER_TYPE_DEFAULT   PNG_FILTER_TYPE_BASE
+
+/* These are for the interlacing type.  These values should NOT be changed. */
+#define PNG_INTERLACE_NONE        0 /* Non-interlaced image */
+#define PNG_INTERLACE_ADAM7       1 /* Adam7 interlacing */
+#define PNG_INTERLACE_LAST        2 /* Not a valid value */
+
+/* These are for the oFFs chunk.  These values should NOT be changed. */
+#define PNG_OFFSET_PIXEL          0 /* Offset in pixels */
+#define PNG_OFFSET_MICROMETER     1 /* Offset in micrometers (1/10^6 meter) */
+#define PNG_OFFSET_LAST           2 /* Not a valid value */
+
+/* These are for the pCAL chunk.  These values should NOT be changed. */
+#define PNG_EQUATION_LINEAR       0 /* Linear transformation */
+#define PNG_EQUATION_BASE_E       1 /* Exponential base e transform */
+#define PNG_EQUATION_ARBITRARY    2 /* Arbitrary base exponential transform */
+#define PNG_EQUATION_HYPERBOLIC   3 /* Hyperbolic sine transformation */
+#define PNG_EQUATION_LAST         4 /* Not a valid value */
+
+/* These are for the sCAL chunk.  These values should NOT be changed. */
+#define PNG_SCALE_UNKNOWN         0 /* unknown unit (image scale) */
+#define PNG_SCALE_METER           1 /* meters per pixel */
+#define PNG_SCALE_RADIAN          2 /* radians per pixel */
+#define PNG_SCALE_LAST            3 /* Not a valid value */
+
+/* These are for the pHYs chunk.  These values should NOT be changed. */
+#define PNG_RESOLUTION_UNKNOWN    0 /* pixels/unknown unit (aspect ratio) */
+#define PNG_RESOLUTION_METER      1 /* pixels/meter */
+#define PNG_RESOLUTION_LAST       2 /* Not a valid value */
+
+/* These are for the sRGB chunk.  These values should NOT be changed. */
+#define PNG_sRGB_INTENT_PERCEPTUAL 0
+#define PNG_sRGB_INTENT_RELATIVE   1
+#define PNG_sRGB_INTENT_SATURATION 2
+#define PNG_sRGB_INTENT_ABSOLUTE   3
+#define PNG_sRGB_INTENT_LAST       4 /* Not a valid value */
+
+/* This is for text chunks */
+#define PNG_KEYWORD_MAX_LENGTH     79
+
+/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
+#define PNG_MAX_PALETTE_LENGTH    256
+
+/* These determine if an ancillary chunk's data has been successfully read
+ * from the PNG header, or if the application has filled in the corresponding
+ * data in the info_struct to be written into the output file.  The values
+ * of the PNG_INFO_<chunk> defines should NOT be changed.
+ */
+#define PNG_INFO_gAMA 0x0001
+#define PNG_INFO_sBIT 0x0002
+#define PNG_INFO_cHRM 0x0004
+#define PNG_INFO_PLTE 0x0008
+#define PNG_INFO_tRNS 0x0010
+#define PNG_INFO_bKGD 0x0020
+#define PNG_INFO_hIST 0x0040
+#define PNG_INFO_pHYs 0x0080
+#define PNG_INFO_oFFs 0x0100
+#define PNG_INFO_tIME 0x0200
+#define PNG_INFO_pCAL 0x0400
+#define PNG_INFO_sRGB 0x0800   /* GR-P, 0.96a */
+#define PNG_INFO_iCCP 0x1000   /* ESR, 1.0.6 */
+#define PNG_INFO_sPLT 0x2000   /* ESR, 1.0.6 */
+#define PNG_INFO_sCAL 0x4000   /* ESR, 1.0.6 */
+#define PNG_INFO_IDAT 0x8000L  /* ESR, 1.0.6 */
+
+/* This is used for the transformation routines, as some of them
+ * change these values for the row.  It also should enable using
+ * the routines for other purposes.
+ */
+typedef struct png_row_info_struct
+{
+   png_uint_32 width; /* width of row */
+   png_uint_32 rowbytes; /* number of bytes in row */
+   png_byte color_type; /* color type of row */
+   png_byte bit_depth; /* bit depth of row */
+   png_byte channels; /* number of channels (1, 2, 3, or 4) */
+   png_byte pixel_depth; /* bits per pixel (depth * channels) */
+} png_row_info;
+
+typedef png_row_info FAR * png_row_infop;
+typedef png_row_info FAR * FAR * png_row_infopp;
+
+/* These are the function types for the I/O functions and for the functions
+ * that allow the user to override the default I/O functions with his or her
+ * own.  The png_error_ptr type should match that of user-supplied warning
+ * and error functions, while the png_rw_ptr type should match that of the
+ * user read/write data functions.
+ */
+typedef struct png_struct_def png_struct;
+typedef png_struct FAR * png_structp;
+
+typedef void (PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp));
+typedef void (PNGAPI *png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
+typedef void (PNGAPI *png_flush_ptr) PNGARG((png_structp));
+typedef void (PNGAPI *png_read_status_ptr) PNGARG((png_structp, png_uint_32,
+   int));
+typedef void (PNGAPI *png_write_status_ptr) PNGARG((png_structp, png_uint_32,
+   int));
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+typedef void (PNGAPI *png_progressive_info_ptr) PNGARG((png_structp, png_infop));
+typedef void (PNGAPI *png_progressive_end_ptr) PNGARG((png_structp, png_infop));
+typedef void (PNGAPI *png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
+   png_uint_32, int));
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_LEGACY_SUPPORTED)
+typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp,
+    png_row_infop, png_bytep));
+#endif
+
+#if defined(PNG_USER_CHUNKS_SUPPORTED)
+typedef int (PNGAPI *png_user_chunk_ptr) PNGARG((png_structp, png_unknown_chunkp));
+#endif
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp));
+#endif
+
+/* Transform masks for the high-level interface */
+#define PNG_TRANSFORM_IDENTITY       0x0000    /* read and write */
+#define PNG_TRANSFORM_STRIP_16       0x0001    /* read only */
+#define PNG_TRANSFORM_STRIP_ALPHA    0x0002    /* read only */
+#define PNG_TRANSFORM_PACKING        0x0004    /* read and write */
+#define PNG_TRANSFORM_PACKSWAP       0x0008    /* read and write */
+#define PNG_TRANSFORM_EXPAND         0x0010    /* read only */
+#define PNG_TRANSFORM_INVERT_MONO    0x0020    /* read and write */
+#define PNG_TRANSFORM_SHIFT          0x0040    /* read and write */
+#define PNG_TRANSFORM_BGR            0x0080    /* read and write */
+#define PNG_TRANSFORM_SWAP_ALPHA     0x0100    /* read and write */
+#define PNG_TRANSFORM_SWAP_ENDIAN    0x0200    /* read and write */
+#define PNG_TRANSFORM_INVERT_ALPHA   0x0400    /* read and write */
+#define PNG_TRANSFORM_STRIP_FILLER   0x0800    /* WRITE only */
+
+/* Flags for MNG supported features */
+#define PNG_FLAG_MNG_EMPTY_PLTE     0x01
+#define PNG_FLAG_MNG_FILTER_64      0x04
+#define PNG_ALL_MNG_FEATURES        0x05
+
+typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
+typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp));
+
+/* The structure that holds the information to read and write PNG files.
+ * The only people who need to care about what is inside of this are the
+ * people who will be modifying the library for their own special needs.
+ * It should NOT be accessed directly by an application, except to store
+ * the jmp_buf.
+ */
+
+struct png_struct_def
+{
+#ifdef PNG_SETJMP_SUPPORTED
+   jmp_buf jmpbuf;            /* used in png_error */
+#endif
+   png_error_ptr error_fn;    /* function for printing errors and aborting */
+   png_error_ptr warning_fn;  /* function for printing warnings */
+   png_voidp error_ptr;       /* user supplied struct for error functions */
+   png_rw_ptr write_data_fn;  /* function for writing output data */
+   png_rw_ptr read_data_fn;   /* function for reading input data */
+   png_voidp io_ptr;          /* ptr to application struct for I/O functions */
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+   png_user_transform_ptr read_user_transform_fn; /* user read transform */
+#endif
+
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+   png_user_transform_ptr write_user_transform_fn; /* user write transform */
+#endif
+
+/* These were added in libpng-1.0.2 */
+#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+   png_voidp user_transform_ptr; /* user supplied struct for user transform */
+   png_byte user_transform_depth;    /* bit depth of user transformed pixels */
+   png_byte user_transform_channels; /* channels in user transformed pixels */
+#endif
+#endif
+
+   png_uint_32 mode;          /* tells us where we are in the PNG file */
+   png_uint_32 flags;         /* flags indicating various things to libpng */
+   png_uint_32 transformations; /* which transformations to perform */
+
+   z_stream zstream;          /* pointer to decompression structure (below) */
+   png_bytep zbuf;            /* buffer for zlib */
+   png_size_t zbuf_size;      /* size of zbuf */
+   int zlib_level;            /* holds zlib compression level */
+   int zlib_method;           /* holds zlib compression method */
+   int zlib_window_bits;      /* holds zlib compression window bits */
+   int zlib_mem_level;        /* holds zlib compression memory level */
+   int zlib_strategy;         /* holds zlib compression strategy */
+
+   png_uint_32 width;         /* width of image in pixels */
+   png_uint_32 height;        /* height of image in pixels */
+   png_uint_32 num_rows;      /* number of rows in current pass */
+   png_uint_32 usr_width;     /* width of row at start of write */
+   png_uint_32 rowbytes;      /* size of row in bytes */
+   png_uint_32 irowbytes;     /* size of current interlaced row in bytes */
+   png_uint_32 iwidth;        /* width of current interlaced row in pixels */
+   png_uint_32 row_number;    /* current row in interlace pass */
+   png_bytep prev_row;        /* buffer to save previous (unfiltered) row */
+   png_bytep row_buf;         /* buffer to save current (unfiltered) row */
+   png_bytep sub_row;         /* buffer to save "sub" row when filtering */
+   png_bytep up_row;          /* buffer to save "up" row when filtering */
+   png_bytep avg_row;         /* buffer to save "avg" row when filtering */
+   png_bytep paeth_row;       /* buffer to save "Paeth" row when filtering */
+   png_row_info row_info;     /* used for transformation routines */
+
+   png_uint_32 idat_size;     /* current IDAT size for read */
+   png_uint_32 crc;           /* current chunk CRC value */
+   png_colorp palette;        /* palette from the input file */
+   png_uint_16 num_palette;   /* number of color entries in palette */
+   png_uint_16 num_trans;     /* number of transparency values */
+   png_byte chunk_name[5];    /* null-terminated name of current chunk */
+   png_byte compression;      /* file compression type (always 0) */
+   png_byte filter;           /* file filter type (always 0) */
+   png_byte interlaced;       /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
+   png_byte pass;             /* current interlace pass (0 - 6) */
+   png_byte do_filter;        /* row filter flags (see PNG_FILTER_ below ) */
+   png_byte color_type;       /* color type of file */
+   png_byte bit_depth;        /* bit depth of file */
+   png_byte usr_bit_depth;    /* bit depth of users row */
+   png_byte pixel_depth;      /* number of bits per pixel */
+   png_byte channels;         /* number of channels in file */
+   png_byte usr_channels;     /* channels at start of write */
+   png_byte sig_bytes;        /* magic bytes read/written from start of file */
+
+#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+#ifdef PNG_LEGACY_SUPPORTED
+   png_byte filler;           /* filler byte for pixel expansion */
+#else
+   png_uint_16 filler;           /* filler bytes for pixel expansion */
+#endif
+#endif
+
+#if defined(PNG_bKGD_SUPPORTED)
+   png_byte background_gamma_type;
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
+   float background_gamma;
+#  endif
+   png_color_16 background;   /* background color in screen gamma space */
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+   png_color_16 background_1; /* background normalized to gamma 1.0 */
+#endif
+#endif /* PNG_bKGD_SUPPORTED */
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+   png_flush_ptr output_flush_fn;/* Function for flushing output */
+   png_uint_32 flush_dist;    /* how many rows apart to flush, 0 - no flush */
+   png_uint_32 flush_rows;    /* number of rows written since last flush */
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+   int gamma_shift;      /* number of "insignificant" bits 16-bit gamma */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   float gamma;          /* file gamma value */
+   float screen_gamma;   /* screen gamma value (display_exponent) */
+#endif
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+   png_bytep gamma_table;     /* gamma table for 8-bit depth files */
+   png_bytep gamma_from_1;    /* converts from 1.0 to screen */
+   png_bytep gamma_to_1;      /* converts from file to 1.0 */
+   png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
+   png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
+   png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
+   png_color_8 sig_bit;       /* significant bits in each available channel */
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
+   png_color_8 shift;         /* shift for significant bit tranformation */
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
+ || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+   png_bytep trans;           /* transparency values for paletted files */
+   png_color_16 trans_values; /* transparency values for non-paletted files */
+#endif
+
+   png_read_status_ptr read_row_fn;   /* called after each row is decoded */
+   png_write_status_ptr write_row_fn; /* called after each row is encoded */
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+   png_progressive_info_ptr info_fn; /* called after header data fully read */
+   png_progressive_row_ptr row_fn;   /* called after each prog. row is decoded */
+   png_progressive_end_ptr end_fn;   /* called after image is complete */
+   png_bytep save_buffer_ptr;        /* current location in save_buffer */
+   png_bytep save_buffer;            /* buffer for previously read data */
+   png_bytep current_buffer_ptr;     /* current location in current_buffer */
+   png_bytep current_buffer;         /* buffer for recently used data */
+   png_uint_32 push_length;          /* size of current input chunk */
+   png_uint_32 skip_length;          /* bytes to skip in input data */
+   png_size_t save_buffer_size;      /* amount of data now in save_buffer */
+   png_size_t save_buffer_max;       /* total size of save_buffer */
+   png_size_t buffer_size;           /* total amount of available input data */
+   png_size_t current_buffer_size;   /* amount of data now in current_buffer */
+   int process_mode;                 /* what push library is currently doing */
+   int cur_palette;                  /* current push library palette index */
+
+#  if defined(PNG_TEXT_SUPPORTED)
+     png_size_t current_text_size;   /* current size of text input data */
+     png_size_t current_text_left;   /* how much text left to read in input */
+     png_charp current_text;         /* current text chunk buffer */
+     png_charp current_text_ptr;     /* current location in current_text */
+#  endif /* PNG_PROGRESSIVE_READ_SUPPORTED && PNG_TEXT_SUPPORTED */
+
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
+/* for the Borland special 64K segment handler */
+   png_bytepp offset_table_ptr;
+   png_bytep offset_table;
+   png_uint_16 offset_table_number;
+   png_uint_16 offset_table_count;
+   png_uint_16 offset_table_count_free;
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+   png_bytep palette_lookup;         /* lookup table for dithering */
+   png_bytep dither_index;           /* index translation for palette files */
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
+   png_uint_16p hist;                /* histogram */
+#endif
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+   png_byte heuristic_method;        /* heuristic for row filter selection */
+   png_byte num_prev_filters;        /* number of weights for previous rows */
+   png_bytep prev_filters;           /* filter type(s) of previous row(s) */
+   png_uint_16p filter_weights;      /* weight(s) for previous line(s) */
+   png_uint_16p inv_filter_weights;  /* 1/weight(s) for previous line(s) */
+   png_uint_16p filter_costs;        /* relative filter calculation cost */
+   png_uint_16p inv_filter_costs;    /* 1/relative filter calculation cost */
+#endif
+
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+   png_charp time_buffer;            /* String to hold RFC 1123 time text */
+#endif
+
+/* New members added in libpng-1.0.6 */
+
+#ifdef PNG_FREE_ME_SUPPORTED
+   png_uint_32 free_me;       /* flags items libpng is responsible for freeing */
+#endif
+
+#if defined(PNG_USER_CHUNKS_SUPPORTED)
+   png_voidp user_chunk_ptr;
+   png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
+#endif
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+   int num_chunk_list;
+   png_bytep chunk_list;
+#endif
+
+/* New members added in libpng-1.0.3 */
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+   png_byte rgb_to_gray_status;
+   /* These were changed from png_byte in libpng-1.0.6 */
+   png_uint_16 rgb_to_gray_red_coeff;
+   png_uint_16 rgb_to_gray_green_coeff;
+   png_uint_16 rgb_to_gray_blue_coeff;
+#endif
+
+/* New member added in libpng-1.0.4 (renamed in 1.0.9) */
+#if defined(PNG_MNG_FEATURES_SUPPORTED) || \
+    defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
+    defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
+/* changed from png_byte to png_uint_32 at version 1.2.0 */
+#ifdef PNG_1_0_X
+   png_byte mng_features_permitted;
+#else
+   png_uint_32 mng_features_permitted;
+#endif /* PNG_1_0_X */
+#endif
+
+/* New member added in libpng-1.0.7 */
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+   png_fixed_point int_gamma;
+#endif
+
+/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+   png_byte filter_type;
+#endif
+
+#if defined(PNG_1_0_X) || (defined(PNG_DEBUG) && defined(PNG_USE_PNGGCCRD))
+/* New member added in libpng-1.0.10, ifdef'ed out in 1.2.0 */
+   png_uint_32 row_buf_size;
+#endif
+
+/* New members added in libpng-1.2.0 */
+#if !defined(PNG_1_0_X) && defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+   png_byte     mmx_bitdepth_threshold;
+   png_uint_32  mmx_rowbytes_threshold;
+   png_uint_32  asm_flags;
+#endif
+
+/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_voidp mem_ptr;                /* user supplied struct for mem functions */
+   png_malloc_ptr malloc_fn;         /* function for allocating memory */
+   png_free_ptr free_fn;             /* function for freeing memory */
+#endif
+
+/* New member added in libpng-1.0.13 and 1.2.0 */
+   png_bytep big_row_buf;         /* buffer to save current (unfiltered) row */
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+/* The following three members were added at version 1.0.14 and 1.2.4 */
+   png_bytep dither_sort;            /* working sort array */
+   png_bytep index_to_palette;       /* where the original index currently is */
+                                     /* in the palette */
+   png_bytep palette_to_index;       /* which original index points to this */
+                                     /* palette color */
+#endif
+
+/* New members added in libpng-1.0.16 and 1.2.6 */
+   png_byte compression_type;
+
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+   png_uint_32 user_width_max;
+   png_uint_32 user_height_max;
+#endif
+
+};
+
+
+/* This triggers a compiler error in png.c, if png.c and png.h
+ * do not agree upon the version number.
+ */
+typedef png_structp version_1_2_8;
+
+typedef png_struct FAR * FAR * png_structpp;
+
+/* Here are the function definitions most commonly used.  This is not
+ * the place to find out how to use libpng.  See libpng.txt for the
+ * full explanation, see example.c for the summary.  This just provides
+ * a simple one line description of the use of each function.
+ */
+
+/* Returns the version number of the library */
+extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void));
+
+/* Tell lib we have already handled the first <num_bytes> magic bytes.
+ * Handling more than 8 bytes from the beginning of the file is an error.
+ */
+extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
+   int num_bytes));
+
+/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
+ * PNG file.  Returns zero if the supplied bytes match the 8-byte PNG
+ * signature, and non-zero otherwise.  Having num_to_check == 0 or
+ * start > 7 will always fail (ie return non-zero).
+ */
+extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
+   png_size_t num_to_check));
+
+/* Simple signature checking function.  This is the same as calling
+ * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
+ */
+extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num));
+
+/* Allocate and initialize png_ptr struct for reading, and any other memory. */
+extern PNG_EXPORT(png_structp,png_create_read_struct)
+   PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
+   png_error_ptr error_fn, png_error_ptr warn_fn));
+
+/* Allocate and initialize png_ptr struct for writing, and any other memory */
+extern PNG_EXPORT(png_structp,png_create_write_struct)
+   PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
+   png_error_ptr error_fn, png_error_ptr warn_fn));
+
+#ifdef PNG_WRITE_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_compression_buffer_size)
+   PNGARG((png_structp png_ptr));
+#endif
+
+#ifdef PNG_WRITE_SUPPORTED
+extern PNG_EXPORT(void,png_set_compression_buffer_size)
+   PNGARG((png_structp png_ptr, png_uint_32 size));
+#endif
+
+/* Reset the compression stream */
+extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr));
+
+/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
+#ifdef PNG_USER_MEM_SUPPORTED
+extern PNG_EXPORT(png_structp,png_create_read_struct_2)
+   PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
+   png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
+   png_malloc_ptr malloc_fn, png_free_ptr free_fn));
+extern PNG_EXPORT(png_structp,png_create_write_struct_2)
+   PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
+   png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
+   png_malloc_ptr malloc_fn, png_free_ptr free_fn));
+#endif
+
+/* Write a PNG chunk - size, type, (optional) data, CRC. */
+extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
+   png_bytep chunk_name, png_bytep data, png_size_t length));
+
+/* Write the start of a PNG chunk - length and chunk name. */
+extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
+   png_bytep chunk_name, png_uint_32 length));
+
+/* Write the data of a PNG chunk started with png_write_chunk_start(). */
+extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
+   png_bytep data, png_size_t length));
+
+/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
+extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
+
+/* Allocate and initialize the info structure */
+extern PNG_EXPORT(png_infop,png_create_info_struct)
+   PNGARG((png_structp png_ptr));
+
+/* Initialize the info structure (old interface - DEPRECATED) */
+extern PNG_EXPORT(void,png_info_init) PNGARG((png_infop info_ptr));
+#undef png_info_init
+#define png_info_init(info_ptr) png_info_init_3(&info_ptr,\
+    png_sizeof(png_info));
+extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr,
+    png_size_t png_info_struct_size));
+
+/* Writes all the PNG information before the image. */
+extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* read the information before the actual image data. */
+extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+#endif
+
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
+   PNGARG((png_structp png_ptr, png_timep ptime));
+#endif
+
+#if !defined(_WIN32_WCE)
+/* "time.h" functions are not supported on WindowsCE */
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+/* convert from a struct tm to png_time */
+extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime,
+   struct tm FAR * ttime));
+
+/* convert from time_t to png_time.  Uses gmtime() */
+extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
+   time_t ttime));
+#endif /* PNG_WRITE_tIME_SUPPORTED */
+#endif /* _WIN32_WCE */
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
+extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
+/* Use blue, green, red order for pixels. */
+extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+/* Expand the grayscale to 24-bit RGB if necessary. */
+extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+/* Reduce RGB to grayscale. */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
+   int error_action, double red, double green ));
+#endif
+extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr,
+   int error_action, png_fixed_point red, png_fixed_point green ));
+extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
+   png_ptr));
+#endif
+
+extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
+   png_colorp palette));
+
+#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
+    defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
+    defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
+extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
+   png_uint_32 filler, int flags));
+/* The values of the PNG_FILLER_ defines should NOT be changed */
+#define PNG_FILLER_BEFORE 0
+#define PNG_FILLER_AFTER 1
+/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
+#if !defined(PNG_1_0_X)
+extern PNG_EXPORT(void,png_set_add_alpha) PNGARG((png_structp png_ptr,
+   png_uint_32 filler, int flags));
+#endif
+#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
+
+#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
+/* Swap bytes in 16-bit depth files. */
+extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
+extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+/* Swap packing order of pixels in bytes. */
+extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
+/* Converts files to legal bit depths. */
+extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr,
+   png_color_8p true_bits));
+#endif
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
+    defined(PNG_WRITE_INTERLACING_SUPPORTED)
+/* Have the code handle the interlacing.  Returns the number of passes. */
+extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
+/* Invert monochrome files */
+extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+/* Handle alpha and tRNS by replacing with a background color. */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
+   png_color_16p background_color, int background_gamma_code,
+   int need_expand, double background_gamma));
+#endif
+#define PNG_BACKGROUND_GAMMA_UNKNOWN 0
+#define PNG_BACKGROUND_GAMMA_SCREEN  1
+#define PNG_BACKGROUND_GAMMA_FILE    2
+#define PNG_BACKGROUND_GAMMA_UNIQUE  3
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+/* strip the second byte of information from a 16-bit depth file. */
+extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+/* Turn on dithering, and reduce the palette to the number of colors available. */
+extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
+   png_colorp palette, int num_palette, int maximum_colors,
+   png_uint_16p histogram, int full_dither));
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+/* Handle gamma correction. Screen_gamma=(display_exponent) */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
+   double screen_gamma, double default_file_gamma));
+#endif
+#endif
+
+#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
+    defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
+/* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */
+/* Deprecated and will be removed.  Use png_permit_mng_features() instead. */
+extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr,
+   int empty_plte_permitted));
+#endif
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+/* Set how many lines between output flushes - 0 for no flushing */
+extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
+/* Flush the current PNG output buffer */
+extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
+#endif
+
+/* optional update palette with requested transformations */
+extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
+
+/* optional call to update the users info structure */
+extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* read one or more rows of image data. */
+extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr,
+   png_bytepp row, png_bytepp display_row, png_uint_32 num_rows));
+#endif
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* read a row of data. */
+extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
+   png_bytep row,
+   png_bytep display_row));
+#endif
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* read the whole image into memory at once. */
+extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
+   png_bytepp image));
+#endif
+
+/* write a row of image data */
+extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
+   png_bytep row));
+
+/* write a few rows of image data */
+extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr,
+   png_bytepp row, png_uint_32 num_rows));
+
+/* write the image data */
+extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
+   png_bytepp image));
+
+/* writes the end of the PNG file. */
+extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* read the end of the PNG file. */
+extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+#endif
+
+/* free any memory associated with the png_info_struct */
+extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr,
+   png_infopp info_ptr_ptr));
+
+/* free any memory associated with the png_struct and the png_info_structs */
+extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp
+   png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
+
+/* free all memory used by the read (old method - NOT DLL EXPORTED) */
+extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_infop end_info_ptr));
+
+/* free any memory associated with the png_struct and the png_info_structs */
+extern PNG_EXPORT(void,png_destroy_write_struct)
+   PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
+
+/* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
+extern void png_write_destroy PNGARG((png_structp png_ptr));
+
+/* set the libpng method of handling chunk CRC errors */
+extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
+   int crit_action, int ancil_action));
+
+/* Values for png_set_crc_action() to say how to handle CRC errors in
+ * ancillary and critical chunks, and whether to use the data contained
+ * therein.  Note that it is impossible to "discard" data in a critical
+ * chunk.  For versions prior to 0.90, the action was always error/quit,
+ * whereas in version 0.90 and later, the action for CRC errors in ancillary
+ * chunks is warn/discard.  These values should NOT be changed.
+ *
+ *      value                       action:critical     action:ancillary
+ */
+#define PNG_CRC_DEFAULT       0  /* error/quit          warn/discard data */
+#define PNG_CRC_ERROR_QUIT    1  /* error/quit          error/quit        */
+#define PNG_CRC_WARN_DISCARD  2  /* (INVALID)           warn/discard data */
+#define PNG_CRC_WARN_USE      3  /* warn/use data       warn/use data     */
+#define PNG_CRC_QUIET_USE     4  /* quiet/use data      quiet/use data    */
+#define PNG_CRC_NO_CHANGE     5  /* use current value   use current value */
+
+/* These functions give the user control over the scan-line filtering in
+ * libpng and the compression methods used by zlib.  These functions are
+ * mainly useful for testing, as the defaults should work with most users.
+ * Those users who are tight on memory or want faster performance at the
+ * expense of compression can modify them.  See the compression library
+ * header file (zlib.h) for an explination of the compression functions.
+ */
+
+/* set the filtering method(s) used by libpng.  Currently, the only valid
+ * value for "method" is 0.
+ */
+extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
+   int filters));
+
+/* Flags for png_set_filter() to say which filters to use.  The flags
+ * are chosen so that they don't conflict with real filter types
+ * below, in case they are supplied instead of the #defined constants.
+ * These values should NOT be changed.
+ */
+#define PNG_NO_FILTERS     0x00
+#define PNG_FILTER_NONE    0x08
+#define PNG_FILTER_SUB     0x10
+#define PNG_FILTER_UP      0x20
+#define PNG_FILTER_AVG     0x40
+#define PNG_FILTER_PAETH   0x80
+#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
+                         PNG_FILTER_AVG | PNG_FILTER_PAETH)
+
+/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
+ * These defines should NOT be changed.
+ */
+#define PNG_FILTER_VALUE_NONE  0
+#define PNG_FILTER_VALUE_SUB   1
+#define PNG_FILTER_VALUE_UP    2
+#define PNG_FILTER_VALUE_AVG   3
+#define PNG_FILTER_VALUE_PAETH 4
+#define PNG_FILTER_VALUE_LAST  5
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
+/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
+ * defines, either the default (minimum-sum-of-absolute-differences), or
+ * the experimental method (weighted-minimum-sum-of-absolute-differences).
+ *
+ * Weights are factors >= 1.0, indicating how important it is to keep the
+ * filter type consistent between rows.  Larger numbers mean the current
+ * filter is that many times as likely to be the same as the "num_weights"
+ * previous filters.  This is cumulative for each previous row with a weight.
+ * There needs to be "num_weights" values in "filter_weights", or it can be
+ * NULL if the weights aren't being specified.  Weights have no influence on
+ * the selection of the first row filter.  Well chosen weights can (in theory)
+ * improve the compression for a given image.
+ *
+ * Costs are factors >= 1.0 indicating the relative decoding costs of a
+ * filter type.  Higher costs indicate more decoding expense, and are
+ * therefore less likely to be selected over a filter with lower computational
+ * costs.  There needs to be a value in "filter_costs" for each valid filter
+ * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
+ * setting the costs.  Costs try to improve the speed of decompression without
+ * unduly increasing the compressed image size.
+ *
+ * A negative weight or cost indicates the default value is to be used, and
+ * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
+ * The default values for both weights and costs are currently 1.0, but may
+ * change if good general weighting/cost heuristics can be found.  If both
+ * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
+ * to the UNWEIGHTED method, but with added encoding time/computation.
+ */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
+   int heuristic_method, int num_weights, png_doublep filter_weights,
+   png_doublep filter_costs));
+#endif
+#endif /*  PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
+
+/* Heuristic used for row filter selection.  These defines should NOT be
+ * changed.
+ */
+#define PNG_FILTER_HEURISTIC_DEFAULT    0  /* Currently "UNWEIGHTED" */
+#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1  /* Used by libpng < 0.95 */
+#define PNG_FILTER_HEURISTIC_WEIGHTED   2  /* Experimental feature */
+#define PNG_FILTER_HEURISTIC_LAST       3  /* Not a valid value */
+
+/* Set the library compression level.  Currently, valid values range from
+ * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
+ * (0 - no compression, 9 - "maximal" compression).  Note that tests have
+ * shown that zlib compression levels 3-6 usually perform as well as level 9
+ * for PNG images, and do considerably fewer caclulations.  In the future,
+ * these values may not correspond directly to the zlib compression levels.
+ */
+extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr,
+   int level));
+
+extern PNG_EXPORT(void,png_set_compression_mem_level)
+   PNGARG((png_structp png_ptr, int mem_level));
+
+extern PNG_EXPORT(void,png_set_compression_strategy)
+   PNGARG((png_structp png_ptr, int strategy));
+
+extern PNG_EXPORT(void,png_set_compression_window_bits)
+   PNGARG((png_structp png_ptr, int window_bits));
+
+extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
+   int method));
+
+/* These next functions are called for input/output, memory, and error
+ * handling.  They are in the file pngrio.c, pngwio.c, and pngerror.c,
+ * and call standard C I/O routines such as fread(), fwrite(), and
+ * fprintf().  These functions can be made to use other I/O routines
+ * at run time for those applications that need to handle I/O in a
+ * different manner by calling png_set_???_fn().  See libpng.txt for
+ * more information.
+ */
+
+#if !defined(PNG_NO_STDIO)
+/* Initialize the input/output for the PNG file to the default functions. */
+extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, png_FILE_p fp));
+#endif
+
+/* Replace the (error and abort), and warning functions with user
+ * supplied functions.  If no messages are to be printed you must still
+ * write and use replacement functions. The replacement error_fn should
+ * still do a longjmp to the last setjmp location if you are using this
+ * method of error handling.  If error_fn or warning_fn is NULL, the
+ * default function will be used.
+ */
+
+extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr,
+   png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
+
+/* Return the user pointer associated with the error functions */
+extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
+
+/* Replace the default data output functions with a user supplied one(s).
+ * If buffered output is not used, then output_flush_fn can be set to NULL.
+ * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
+ * output_flush_fn will be ignored (and thus can be NULL).
+ */
+extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
+   png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
+
+/* Replace the default data input function with a user supplied one. */
+extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
+   png_voidp io_ptr, png_rw_ptr read_data_fn));
+
+/* Return the user pointer associated with the I/O functions */
+extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
+
+extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr,
+   png_read_status_ptr read_row_fn));
+
+extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr,
+   png_write_status_ptr write_row_fn));
+
+#ifdef PNG_USER_MEM_SUPPORTED
+/* Replace the default memory allocation functions with user supplied one(s). */
+extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
+   png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
+/* Return the user pointer associated with the memory functions */
+extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_LEGACY_SUPPORTED)
+extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp
+   png_ptr, png_user_transform_ptr read_user_transform_fn));
+#endif
+
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_LEGACY_SUPPORTED)
+extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
+   png_ptr, png_user_transform_ptr write_user_transform_fn));
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_LEGACY_SUPPORTED)
+extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp
+   png_ptr, png_voidp user_transform_ptr, int user_transform_depth,
+   int user_transform_channels));
+/* Return the user pointer associated with the user transform functions */
+extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
+   PNGARG((png_structp png_ptr));
+#endif
+
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+extern PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr,
+   png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
+extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp
+   png_ptr));
+#endif
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+/* Sets the function callbacks for the push reader, and a pointer to a
+ * user-defined structure available to the callback functions.
+ */
+extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
+   png_voidp progressive_ptr,
+   png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
+   png_progressive_end_ptr end_fn));
+
+/* returns the user pointer associated with the push read functions */
+extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
+   PNGARG((png_structp png_ptr));
+
+/* function to be called when data becomes available */
+extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_bytep buffer, png_size_t buffer_size));
+
+/* function that combines rows.  Not very much different than the
+ * png_combine_row() call.  Is this even used?????
+ */
+extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
+   png_bytep old_row, png_bytep new_row));
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
+   png_uint_32 size));
+
+#if defined(PNG_1_0_X)
+#  define png_malloc_warn png_malloc
+#else
+/* Added at libpng version 1.2.4 */
+extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr,
+   png_uint_32 size));
+#endif
+
+/* frees a pointer allocated by png_malloc() */
+extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
+
+#if defined(PNG_1_0_X)
+/* Function to allocate memory for zlib. */
+extern PNG_EXPORT(voidpf,png_zalloc) PNGARG((voidpf png_ptr, uInt items,
+   uInt size));
+
+/* Function to free memory for zlib */
+extern PNG_EXPORT(void,png_zfree) PNGARG((voidpf png_ptr, voidpf ptr));
+#endif
+
+/* Free data that was allocated internally */
+extern PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_32 free_me, int num));
+#ifdef PNG_FREE_ME_SUPPORTED
+/* Reassign responsibility for freeing existing data, whether allocated
+ * by libpng or by the application */
+extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, int freer, png_uint_32 mask));
+#endif
+/* assignments for png_data_freer */
+#define PNG_DESTROY_WILL_FREE_DATA 1
+#define PNG_SET_WILL_FREE_DATA 1
+#define PNG_USER_WILL_FREE_DATA 2
+/* Flags for png_ptr->free_me and info_ptr->free_me */
+#define PNG_FREE_HIST 0x0008
+#define PNG_FREE_ICCP 0x0010
+#define PNG_FREE_SPLT 0x0020
+#define PNG_FREE_ROWS 0x0040
+#define PNG_FREE_PCAL 0x0080
+#define PNG_FREE_SCAL 0x0100
+#define PNG_FREE_UNKN 0x0200
+#define PNG_FREE_LIST 0x0400
+#define PNG_FREE_PLTE 0x1000
+#define PNG_FREE_TRNS 0x2000
+#define PNG_FREE_TEXT 0x4000
+#define PNG_FREE_ALL  0x7fff
+#define PNG_FREE_MUL  0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
+
+#ifdef PNG_USER_MEM_SUPPORTED
+extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
+   png_uint_32 size));
+extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
+   png_voidp ptr));
+#endif
+
+extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
+   png_voidp s1, png_voidp s2, png_uint_32 size));
+
+extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
+   png_voidp s1, int value, png_uint_32 size));
+
+#if defined(USE_FAR_KEYWORD)  /* memory model conversion function */
+extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
+   int check));
+#endif /* USE_FAR_KEYWORD */
+
+/* Fatal error in PNG image of libpng - can't continue */
+extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
+   png_const_charp error_message));
+
+/* The same, but the chunk name is prepended to the error string. */
+extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
+   png_const_charp error_message));
+
+/* Non-fatal error in libpng.  Can continue, but may have a problem. */
+extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
+   png_const_charp warning_message));
+
+/* Non-fatal error in libpng, chunk name is prepended to message. */
+extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
+   png_const_charp warning_message));
+
+/* The png_set_<chunk> functions are for storing values in the png_info_struct.
+ * Similarly, the png_get_<chunk> calls are used to read values from the
+ * png_info_struct, either storing the parameters in the passed variables, or
+ * setting pointers into the png_info_struct where the data is stored.  The
+ * png_get_<chunk> functions return a non-zero value if the data was available
+ * in info_ptr, or return zero and do not change any of the parameters if the
+ * data was not available.
+ *
+ * These functions should be used instead of directly accessing png_info
+ * to avoid problems with future changes in the size and internal layout of
+ * png_info_struct.
+ */
+/* Returns "flag" if chunk data is valid in info_ptr. */
+extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
+png_infop info_ptr, png_uint_32 flag));
+
+/* Returns number of bytes needed to hold a transformed row. */
+extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+/* Returns row_pointers, which is an array of pointers to scanlines that was
+returned from png_read_png(). */
+extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+/* Set row_pointers, which is an array of pointers to scanlines for use
+by png_write_png(). */
+extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_bytepp row_pointers));
+#endif
+
+/* Returns number of color channels in image. */
+extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+#ifdef PNG_EASY_ACCESS_SUPPORTED
+/* Returns image width in pixels. */
+extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image height in pixels. */
+extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image bit_depth. */
+extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image color_type. */
+extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image filter_type. */
+extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image interlace_type. */
+extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image compression_type. */
+extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image resolution in pixels per meter, from pHYs chunk data. */
+extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns pixel aspect ratio, computed from pHYs chunk data.  */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+#endif
+
+/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
+extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+#endif /* PNG_EASY_ACCESS_SUPPORTED */
+
+/* Returns pointer to signature string read from PNG header */
+extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
+png_infop info_ptr));
+
+#if defined(PNG_bKGD_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_color_16p *background));
+#endif
+
+#if defined(PNG_bKGD_SUPPORTED)
+extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_color_16p background));
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, double *white_x, double *white_y, double *red_x,
+   double *red_y, double *green_x, double *green_y, double *blue_x,
+   double *blue_y));
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_fixed_point *int_white_x, png_fixed_point
+   *int_white_y, png_fixed_point *int_red_x, png_fixed_point *int_red_y,
+   png_fixed_point *int_green_x, png_fixed_point *int_green_y, png_fixed_point
+   *int_blue_x, png_fixed_point *int_blue_y));
+#endif
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, double white_x, double white_y, double red_x,
+   double red_y, double green_x, double green_y, double blue_x, double blue_y));
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_fixed_point int_white_x, png_fixed_point int_white_y,
+   png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
+   int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
+   png_fixed_point int_blue_y));
+#endif
+#endif
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, double *file_gamma));
+#endif
+extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_fixed_point *int_file_gamma));
+#endif
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, double file_gamma));
+#endif
+extern PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_fixed_point int_file_gamma));
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_16p *hist));
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_16p hist));
+#endif
+
+extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
+   int *bit_depth, int *color_type, int *interlace_method,
+   int *compression_method, int *filter_method));
+
+extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
+   int color_type, int interlace_method, int compression_method,
+   int filter_method));
+
+#if defined(PNG_oFFs_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
+   int *unit_type));
+#endif
+
+#if defined(PNG_oFFs_SUPPORTED)
+extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y,
+   int unit_type));
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
+   int *type, int *nparams, png_charp *units, png_charpp *params));
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
+   int type, int nparams, png_charp units, png_charpp params));
+#endif
+
+#if defined(PNG_pHYs_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
+#endif
+
+#if defined(PNG_pHYs_SUPPORTED)
+extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
+#endif
+
+extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_colorp *palette, int *num_palette));
+
+extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_colorp palette, int num_palette));
+
+#if defined(PNG_sBIT_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_color_8p *sig_bit));
+#endif
+
+#if defined(PNG_sBIT_SUPPORTED)
+extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_color_8p sig_bit));
+#endif
+
+#if defined(PNG_sRGB_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, int *intent));
+#endif
+
+#if defined(PNG_sRGB_SUPPORTED)
+extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, int intent));
+extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, int intent));
+#endif
+
+#if defined(PNG_iCCP_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_charpp name, int *compression_type,
+   png_charpp profile, png_uint_32 *proflen));
+   /* Note to maintainer: profile should be png_bytepp */
+#endif
+
+#if defined(PNG_iCCP_SUPPORTED)
+extern PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_charp name, int compression_type,
+   png_charp profile, png_uint_32 proflen));
+   /* Note to maintainer: profile should be png_bytep */
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_sPLT_tpp entries));
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+extern PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_sPLT_tp entries, int nentries));
+#endif
+
+#if defined(PNG_TEXT_SUPPORTED)
+/* png_get_text also returns the number of text chunks in *num_text */
+extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_textp *text_ptr, int *num_text));
+#endif
+
+/*
+ *  Note while png_set_text() will accept a structure whose text,
+ *  language, and  translated keywords are NULL pointers, the structure
+ *  returned by png_get_text will always contain regular
+ *  zero-terminated C strings.  They might be empty strings but
+ *  they will never be NULL pointers.
+ */
+
+#if defined(PNG_TEXT_SUPPORTED)
+extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_textp text_ptr, int num_text));
+#endif
+
+#if defined(PNG_tIME_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_timep *mod_time));
+#endif
+
+#if defined(PNG_tIME_SUPPORTED)
+extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_timep mod_time));
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_bytep *trans, int *num_trans,
+   png_color_16p *trans_values));
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_bytep trans, int num_trans,
+   png_color_16p trans_values));
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+#endif
+
+#if defined(PNG_sCAL_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, int *unit, double *width, double *height));
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight));
+#endif
+#endif
+#endif /* PNG_sCAL_SUPPORTED */
+
+#if defined(PNG_sCAL_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, int unit, double width, double height));
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, int unit, png_charp swidth, png_charp sheight));
+#endif
+#endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+/* provide a list of chunks and how they are to be handled, if the built-in
+   handling or default unknown chunk handling is not desired.  Any chunks not
+   listed will be handled in the default manner.  The IHDR and IEND chunks
+   must not be listed.
+      keep = 0: follow default behavour
+           = 1: do not keep
+           = 2: keep only if safe-to-copy
+           = 3: keep even if unsafe-to-copy
+*/
+extern PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp
+   png_ptr, int keep, png_bytep chunk_list, int num_chunks));
+extern PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns));
+extern PNG_EXPORT(void, png_set_unknown_chunk_location)
+   PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location));
+extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp
+   png_ptr, png_infop info_ptr, png_unknown_chunkpp entries));
+#endif
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep
+   chunk_name));
+#endif
+
+/* Png_free_data() will turn off the "valid" flag for anything it frees.
+   If you need to turn it off for a chunk that your application has freed,
+   you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); */
+extern PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr,
+   png_infop info_ptr, int mask));
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+/* The "params" pointer is currently not used and is for future expansion. */
+extern PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr,
+                        png_infop info_ptr,
+                        int transforms,
+                        png_voidp params));
+extern PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr,
+                        png_infop info_ptr,
+                        int transforms,
+                        png_voidp params));
+#endif
+
+/* Define PNG_DEBUG at compile time for debugging information.  Higher
+ * numbers for PNG_DEBUG mean more debugging information.  This has
+ * only been added since version 0.95 so it is not implemented throughout
+ * libpng yet, but more support will be added as needed.
+ */
+#ifdef PNG_DEBUG
+#if (PNG_DEBUG > 0)
+#if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER)
+#include <crtdbg.h>
+#if (PNG_DEBUG > 1)
+#define png_debug(l,m)  _RPT0(_CRT_WARN,m)
+#define png_debug1(l,m,p1)  _RPT1(_CRT_WARN,m,p1)
+#define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m,p1,p2)
+#endif
+#else /* PNG_DEBUG_FILE || !_MSC_VER */
+#ifndef PNG_DEBUG_FILE
+#define PNG_DEBUG_FILE stderr
+#endif /* PNG_DEBUG_FILE */
+#if (PNG_DEBUG > 1)
+#define png_debug(l,m) \
+{ \
+     int num_tabs=l; \
+     fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
+       (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
+}
+#define png_debug1(l,m,p1) \
+{ \
+     int num_tabs=l; \
+     fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
+       (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
+}
+#define png_debug2(l,m,p1,p2) \
+{ \
+     int num_tabs=l; \
+     fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
+       (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
+}
+#endif /* (PNG_DEBUG > 1) */
+#endif /* _MSC_VER */
+#endif /* (PNG_DEBUG > 0) */
+#endif /* PNG_DEBUG */
+#ifndef png_debug
+#define png_debug(l, m)
+#endif
+#ifndef png_debug1
+#define png_debug1(l, m, p1)
+#endif
+#ifndef png_debug2
+#define png_debug2(l, m, p1, p2)
+#endif
+
+extern PNG_EXPORT(png_bytep,png_sig_bytes) PNGARG((void));
+
+extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr));
+
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp
+   png_ptr, png_uint_32 mng_features_permitted));
+#endif
+
+/* For use in png_set_keep_unknown, added to version 1.2.6 */
+#define PNG_HANDLE_CHUNK_AS_DEFAULT   0
+#define PNG_HANDLE_CHUNK_NEVER        1
+#define PNG_HANDLE_CHUNK_IF_SAFE      2
+#define PNG_HANDLE_CHUNK_ALWAYS       3
+
+/* Added to version 1.2.0 */
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+#define PNG_ASM_FLAG_MMX_SUPPORT_COMPILED  0x01  /* not user-settable */
+#define PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU    0x02  /* not user-settable */
+#define PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  0x04
+#define PNG_ASM_FLAG_MMX_READ_INTERLACE    0x08
+#define PNG_ASM_FLAG_MMX_READ_FILTER_SUB   0x10
+#define PNG_ASM_FLAG_MMX_READ_FILTER_UP    0x20
+#define PNG_ASM_FLAG_MMX_READ_FILTER_AVG   0x40
+#define PNG_ASM_FLAG_MMX_READ_FILTER_PAETH 0x80
+#define PNG_ASM_FLAGS_INITIALIZED          0x80000000  /* not user-settable */
+
+#define PNG_MMX_READ_FLAGS ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
+                           | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
+                           | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
+                           | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
+                           | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
+                           | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH )
+#define PNG_MMX_WRITE_FLAGS ( 0 )
+
+#define PNG_MMX_FLAGS ( PNG_ASM_FLAG_MMX_SUPPORT_COMPILED \
+                      | PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU   \
+                      | PNG_MMX_READ_FLAGS                \
+                      | PNG_MMX_WRITE_FLAGS )
+
+#define PNG_SELECT_READ   1
+#define PNG_SELECT_WRITE  2
+
+#if !defined(PNG_1_0_X)
+/* pngget.c */
+extern PNG_EXPORT(png_uint_32,png_get_mmx_flagmask)
+   PNGARG((int flag_select, int *compilerID));
+
+/* pngget.c */
+extern PNG_EXPORT(png_uint_32,png_get_asm_flagmask)
+   PNGARG((int flag_select));
+
+/* pngget.c */
+extern PNG_EXPORT(png_uint_32,png_get_asm_flags)
+   PNGARG((png_structp png_ptr));
+
+/* pngget.c */
+extern PNG_EXPORT(png_byte,png_get_mmx_bitdepth_threshold)
+   PNGARG((png_structp png_ptr));
+
+/* pngget.c */
+extern PNG_EXPORT(png_uint_32,png_get_mmx_rowbytes_threshold)
+   PNGARG((png_structp png_ptr));
+
+/* pngset.c */
+extern PNG_EXPORT(void,png_set_asm_flags)
+   PNGARG((png_structp png_ptr, png_uint_32 asm_flags));
+
+/* pngset.c */
+extern PNG_EXPORT(void,png_set_mmx_thresholds)
+   PNGARG((png_structp png_ptr, png_byte mmx_bitdepth_threshold,
+   png_uint_32 mmx_rowbytes_threshold));
+
+#endif /* PNG_1_0_X */
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+
+#if !defined(PNG_1_0_X)
+/* png.c, pnggccrd.c, or pngvcrd.c */
+extern PNG_EXPORT(int,png_mmx_support) PNGARG((void));
+
+/* Strip the prepended error numbers ("#nnn ") from error and warning
+ * messages before passing them to the error or warning handler. */
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
+   png_ptr, png_uint_32 strip_mode));
+#endif
+
+#endif /* PNG_1_0_X */
+
+/* Added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+extern PNG_EXPORT(void,png_set_user_limits) PNGARG((png_structp
+   png_ptr, png_uint_32 user_width_max, png_uint_32 user_height_max));
+extern PNG_EXPORT(png_uint_32,png_get_user_width_max) PNGARG((png_structp
+   png_ptr));
+extern PNG_EXPORT(png_uint_32,png_get_user_height_max) PNGARG((png_structp
+   png_ptr));
+#endif
+
+/* Maintainer: Put new public prototypes here ^, in libpng.3, and project defs */
+
+#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
+/* With these routines we avoid an integer divide, which will be slower on
+ * most machines.  However, it does take more operations than the corresponding
+ * divide method, so it may be slower on a few RISC systems.  There are two
+ * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
+ *
+ * Note that the rounding factors are NOT supposed to be the same!  128 and
+ * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
+ * standard method.
+ *
+ * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
+ */
+
+ /* fg and bg should be in `gamma 1.0' space; alpha is the opacity          */
+
+#  define png_composite(composite, fg, alpha, bg)                            \
+     { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) * (png_uint_16)(alpha) \
+                        +        (png_uint_16)(bg)*(png_uint_16)(255 -       \
+                        (png_uint_16)(alpha)) + (png_uint_16)128);           \
+       (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
+
+#  define png_composite_16(composite, fg, alpha, bg)                         \
+     { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) * (png_uint_32)(alpha) \
+                        + (png_uint_32)(bg)*(png_uint_32)(65535L -           \
+                        (png_uint_32)(alpha)) + (png_uint_32)32768L);        \
+       (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
+
+#else  /* standard method using integer division */
+
+#  define png_composite(composite, fg, alpha, bg)                            \
+     (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) +    \
+       (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) +       \
+       (png_uint_16)127) / 255)
+
+#  define png_composite_16(composite, fg, alpha, bg)                         \
+     (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
+       (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) +      \
+       (png_uint_32)32767) / (png_uint_32)65535L)
+
+#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
+
+/* These next functions are used internally in the code.  They generally
+ * shouldn't be used unless you are writing code to add or replace some
+ * functionality in libpng.  More information about most functions can
+ * be found in the files where the functions are located.
+ */
+
+#if defined(PNG_INTERNAL)
+
+/* Various modes of operation.  Note that after an init, mode is set to
+ * zero automatically when the structure is created.
+ */
+#define PNG_HAVE_IHDR               0x01
+#define PNG_HAVE_PLTE               0x02
+#define PNG_HAVE_IDAT               0x04
+#define PNG_AFTER_IDAT              0x08
+#define PNG_HAVE_IEND               0x10
+#define PNG_HAVE_gAMA               0x20
+#define PNG_HAVE_cHRM               0x40
+#define PNG_HAVE_sRGB               0x80
+#define PNG_HAVE_CHUNK_HEADER      0x100
+#define PNG_WROTE_tIME             0x200
+#define PNG_WROTE_INFO_BEFORE_PLTE 0x400
+#define PNG_BACKGROUND_IS_GRAY     0x800
+#define PNG_HAVE_PNG_SIGNATURE    0x1000
+
+/* flags for the transformations the PNG library does on the image data */
+#define PNG_BGR                0x0001
+#define PNG_INTERLACE          0x0002
+#define PNG_PACK               0x0004
+#define PNG_SHIFT              0x0008
+#define PNG_SWAP_BYTES         0x0010
+#define PNG_INVERT_MONO        0x0020
+#define PNG_DITHER             0x0040
+#define PNG_BACKGROUND         0x0080
+#define PNG_BACKGROUND_EXPAND  0x0100
+                          /*   0x0200 unused */
+#define PNG_16_TO_8            0x0400
+#define PNG_RGBA               0x0800
+#define PNG_EXPAND             0x1000
+#define PNG_GAMMA              0x2000
+#define PNG_GRAY_TO_RGB        0x4000
+#define PNG_FILLER             0x8000L
+#define PNG_PACKSWAP          0x10000L
+#define PNG_SWAP_ALPHA        0x20000L
+#define PNG_STRIP_ALPHA       0x40000L
+#define PNG_INVERT_ALPHA      0x80000L
+#define PNG_USER_TRANSFORM   0x100000L
+#define PNG_RGB_TO_GRAY_ERR  0x200000L
+#define PNG_RGB_TO_GRAY_WARN 0x400000L
+#define PNG_RGB_TO_GRAY      0x600000L  /* two bits, RGB_TO_GRAY_ERR|WARN */
+                       /*    0x800000L     Unused */
+#define PNG_ADD_ALPHA       0x1000000L  /* Added to libpng-1.2.7 */
+                       /*   0x2000000L  unused */
+                       /*   0x4000000L  unused */
+                       /*   0x8000000L  unused */
+                       /*  0x10000000L  unused */
+                       /*  0x20000000L  unused */
+                       /*  0x40000000L  unused */
+
+/* flags for png_create_struct */
+#define PNG_STRUCT_PNG   0x0001
+#define PNG_STRUCT_INFO  0x0002
+
+/* Scaling factor for filter heuristic weighting calculations */
+#define PNG_WEIGHT_SHIFT 8
+#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
+#define PNG_COST_SHIFT 3
+#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
+
+/* flags for the png_ptr->flags rather than declaring a byte for each one */
+#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY     0x0001
+#define PNG_FLAG_ZLIB_CUSTOM_LEVEL        0x0002
+#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL    0x0004
+#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS  0x0008
+#define PNG_FLAG_ZLIB_CUSTOM_METHOD       0x0010
+#define PNG_FLAG_ZLIB_FINISHED            0x0020
+#define PNG_FLAG_ROW_INIT                 0x0040
+#define PNG_FLAG_FILLER_AFTER             0x0080
+#define PNG_FLAG_CRC_ANCILLARY_USE        0x0100
+#define PNG_FLAG_CRC_ANCILLARY_NOWARN     0x0200
+#define PNG_FLAG_CRC_CRITICAL_USE         0x0400
+#define PNG_FLAG_CRC_CRITICAL_IGNORE      0x0800
+#define PNG_FLAG_FREE_PLTE                0x1000
+#define PNG_FLAG_FREE_TRNS                0x2000
+#define PNG_FLAG_FREE_HIST                0x4000
+#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS      0x8000L
+#define PNG_FLAG_KEEP_UNSAFE_CHUNKS       0x10000L
+#define PNG_FLAG_LIBRARY_MISMATCH         0x20000L
+#define PNG_FLAG_STRIP_ERROR_NUMBERS      0x40000L
+#define PNG_FLAG_STRIP_ERROR_TEXT         0x80000L
+#define PNG_FLAG_MALLOC_NULL_MEM_OK       0x100000L
+#define PNG_FLAG_ADD_ALPHA                0x200000L  /* Added to libpng-1.2.8 */
+#define PNG_FLAG_STRIP_ALPHA              0x400000L  /* Added to libpng-1.2.8 */
+                                  /*      0x800000L  unused */
+                                  /*     0x1000000L  unused */
+                                  /*     0x2000000L  unused */
+                                  /*     0x4000000L  unused */
+                                  /*     0x8000000L  unused */
+                                  /*    0x10000000L  unused */
+                                  /*    0x20000000L  unused */
+                                  /*    0x40000000L  unused */
+
+#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
+                                     PNG_FLAG_CRC_ANCILLARY_NOWARN)
+
+#define PNG_FLAG_CRC_CRITICAL_MASK  (PNG_FLAG_CRC_CRITICAL_USE | \
+                                     PNG_FLAG_CRC_CRITICAL_IGNORE)
+
+#define PNG_FLAG_CRC_MASK           (PNG_FLAG_CRC_ANCILLARY_MASK | \
+                                     PNG_FLAG_CRC_CRITICAL_MASK)
+
+/* save typing and make code easier to understand */
+
+#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
+   abs((int)((c1).green) - (int)((c2).green)) + \
+   abs((int)((c1).blue) - (int)((c2).blue)))
+
+/* Added to libpng-1.2.6 JB */
+#define PNG_ROWBYTES(pixel_bits, width) \
+    ((pixel_bits) >= 8 ? \
+    ((width) * (((png_uint_32)(pixel_bits)) >> 3)) : \
+    (( ((width) * ((png_uint_32)(pixel_bits))) + 7) >> 3) )
+
+/* PNG_OUT_OF_RANGE returns true if value is outside the range
+   ideal-delta..ideal+delta.  Each argument is evaluated twice.
+   "ideal" and "delta" should be constants, normally simple
+   integers, "value" a variable. Added to libpng-1.2.6 JB */
+#define PNG_OUT_OF_RANGE(value, ideal, delta) \
+        ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
+
+/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
+#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
+/* place to hold the signature string for a PNG file. */
+#ifdef PNG_USE_GLOBAL_ARRAYS
+   PNG_EXPORT_VAR (const png_byte FARDATA) png_sig[8];
+#else
+#define png_sig png_sig_bytes(NULL)
+#endif
+#endif /* PNG_NO_EXTERN */
+
+/* Constant strings for known chunk types.  If you need to add a chunk,
+ * define the name here, and add an invocation of the macro in png.c and
+ * wherever it's needed.
+ */
+#define PNG_IHDR const png_byte png_IHDR[5] = { 73,  72,  68,  82, '\0'}
+#define PNG_IDAT const png_byte png_IDAT[5] = { 73,  68,  65,  84, '\0'}
+#define PNG_IEND const png_byte png_IEND[5] = { 73,  69,  78,  68, '\0'}
+#define PNG_PLTE const png_byte png_PLTE[5] = { 80,  76,  84,  69, '\0'}
+#define PNG_bKGD const png_byte png_bKGD[5] = { 98,  75,  71,  68, '\0'}
+#define PNG_cHRM const png_byte png_cHRM[5] = { 99,  72,  82,  77, '\0'}
+#define PNG_gAMA const png_byte png_gAMA[5] = {103,  65,  77,  65, '\0'}
+#define PNG_hIST const png_byte png_hIST[5] = {104,  73,  83,  84, '\0'}
+#define PNG_iCCP const png_byte png_iCCP[5] = {105,  67,  67,  80, '\0'}
+#define PNG_iTXt const png_byte png_iTXt[5] = {105,  84,  88, 116, '\0'}
+#define PNG_oFFs const png_byte png_oFFs[5] = {111,  70,  70, 115, '\0'}
+#define PNG_pCAL const png_byte png_pCAL[5] = {112,  67,  65,  76, '\0'}
+#define PNG_sCAL const png_byte png_sCAL[5] = {115,  67,  65,  76, '\0'}
+#define PNG_pHYs const png_byte png_pHYs[5] = {112,  72,  89, 115, '\0'}
+#define PNG_sBIT const png_byte png_sBIT[5] = {115,  66,  73,  84, '\0'}
+#define PNG_sPLT const png_byte png_sPLT[5] = {115,  80,  76,  84, '\0'}
+#define PNG_sRGB const png_byte png_sRGB[5] = {115,  82,  71,  66, '\0'}
+#define PNG_tEXt const png_byte png_tEXt[5] = {116,  69,  88, 116, '\0'}
+#define PNG_tIME const png_byte png_tIME[5] = {116,  73,  77,  69, '\0'}
+#define PNG_tRNS const png_byte png_tRNS[5] = {116,  82,  78,  83, '\0'}
+#define PNG_zTXt const png_byte png_zTXt[5] = {122,  84,  88, 116, '\0'}
+
+#ifdef PNG_USE_GLOBAL_ARRAYS
+PNG_EXPORT_VAR (const png_byte FARDATA) png_IHDR[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_IDAT[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_IEND[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_PLTE[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_bKGD[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_cHRM[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_gAMA[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_hIST[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_iCCP[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_iTXt[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_oFFs[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_pCAL[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_sCAL[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_pHYs[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_sBIT[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_sPLT[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_sRGB[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_tEXt[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_tIME[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_tRNS[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_zTXt[5];
+#endif /* PNG_USE_GLOBAL_ARRAYS */
+
+
+/* Inline macros to do direct reads of bytes from the input buffer.  These
+ * require that you are using an architecture that uses PNG byte ordering
+ * (MSB first) and supports unaligned data storage.  I think that PowerPC
+ * in big-endian mode and 680x0 are the only ones that will support this.
+ * The x86 line of processors definitely do not.  The png_get_int_32()
+ * routine also assumes we are using two's complement format for negative
+ * values, which is almost certainly true.
+ */
+#if defined(PNG_READ_BIG_ENDIAN_SUPPORTED)
+#  if defined(PNG_pCAL_SUPPORTED) || defined(PNG_oFFs_SUPPORTED)
+#    define png_get_int_32(buf) ( *((png_int_32p) (buf)))
+#  endif
+#  define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
+#  define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
+#else
+#  if defined(PNG_pCAL_SUPPORTED) || defined(PNG_oFFs_SUPPORTED)
+PNG_EXTERN png_int_32 png_get_int_32 PNGARG((png_bytep buf));
+#  endif
+PNG_EXTERN png_uint_32 png_get_uint_32 PNGARG((png_bytep buf));
+PNG_EXTERN png_uint_16 png_get_uint_16 PNGARG((png_bytep buf));
+#endif /* !PNG_READ_BIG_ENDIAN_SUPPORTED */
+PNG_EXTERN png_uint_32 png_get_uint_31 PNGARG((png_structp png_ptr,
+  png_bytep buf));
+
+/* Initialize png_ptr struct for reading, and allocate any other memory.
+ * (old interface - DEPRECATED - use png_create_read_struct instead).
+ */
+extern PNG_EXPORT(void,png_read_init) PNGARG((png_structp png_ptr));
+#undef png_read_init
+#define png_read_init(png_ptr) png_read_init_3(&png_ptr, \
+    PNG_LIBPNG_VER_STRING,  png_sizeof(png_struct));
+extern PNG_EXPORT(void,png_read_init_3) PNGARG((png_structpp ptr_ptr,
+    png_const_charp user_png_ver, png_size_t png_struct_size));
+extern PNG_EXPORT(void,png_read_init_2) PNGARG((png_structp png_ptr,
+    png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
+    png_info_size));
+
+/* Initialize png_ptr struct for writing, and allocate any other memory.
+ * (old interface - DEPRECATED - use png_create_write_struct instead).
+ */
+extern PNG_EXPORT(void,png_write_init) PNGARG((png_structp png_ptr));
+#undef png_write_init
+#define png_write_init(png_ptr) png_write_init_3(&png_ptr, \
+    PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
+extern PNG_EXPORT(void,png_write_init_3) PNGARG((png_structpp ptr_ptr,
+    png_const_charp user_png_ver, png_size_t png_struct_size));
+extern PNG_EXPORT(void,png_write_init_2) PNGARG((png_structp png_ptr,
+    png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
+    png_info_size));
+
+/* Allocate memory for an internal libpng struct */
+PNG_EXTERN png_voidp png_create_struct PNGARG((int type));
+
+/* Free memory from internal libpng struct */
+PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
+
+PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
+  malloc_fn, png_voidp mem_ptr));
+PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
+   png_free_ptr free_fn, png_voidp mem_ptr));
+
+/* Free any memory that info_ptr points to and reset struct. */
+PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+
+#ifndef PNG_1_0_X
+/* Function to allocate memory for zlib. */
+PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));
+
+/* Function to free memory for zlib */
+PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
+
+#ifdef PNG_SIZE_T
+/* Function to convert a sizeof an item to png_sizeof item */
+   PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size));
+#endif
+
+/* Next four functions are used internally as callbacks.  PNGAPI is required
+ * but not PNG_EXPORT.  PNGAPI added at libpng version 1.2.3. */
+
+PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr,
+   png_bytep data, png_size_t length));
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
+   png_bytep buffer, png_size_t length));
+#endif
+
+PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr,
+   png_bytep data, png_size_t length));
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+#if !defined(PNG_NO_STDIO)
+PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr));
+#endif
+#endif
+#else /* PNG_1_0_X */
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
+   png_bytep buffer, png_size_t length));
+#endif
+#endif /* PNG_1_0_X */
+
+/* Reset the CRC variable */
+PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
+
+/* Write the "data" buffer to whatever output you are using. */
+PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
+   png_size_t length));
+
+/* Read data from whatever input you are using into the "data" buffer */
+PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
+   png_size_t length));
+
+/* Read bytes into buf, and update png_ptr->crc */
+PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
+   png_size_t length));
+
+/* Decompress data in a chunk that uses compression */
+#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
+    defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
+PNG_EXTERN png_charp png_decompress_chunk PNGARG((png_structp png_ptr,
+   int comp_type, png_charp chunkdata, png_size_t chunklength,
+   png_size_t prefix_length, png_size_t *data_length));
+#endif
+
+/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
+PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
+
+/* Read the CRC from the file and compare it to the libpng calculated CRC */
+PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
+
+/* Calculate the CRC over a section of data.  Note that we are only
+ * passing a maximum of 64K on systems that have this as a memory limit,
+ * since this is the maximum buffer size we can specify.
+ */
+PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
+   png_size_t length));
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
+#endif
+
+
+/* Place a 32-bit number into a buffer in PNG byte order (big-endian).
+ * The only currently known PNG chunks that use signed numbers are
+ * the ancillary extension chunks, oFFs and pCAL.
+ */
+PNG_EXTERN void png_save_uint_32 PNGARG((png_bytep buf, png_uint_32 i));
+
+#if defined(PNG_WRITE_pCAL_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
+PNG_EXTERN void png_save_int_32 PNGARG((png_bytep buf, png_int_32 i));
+#endif
+
+/* Place a 16-bit number into a buffer in PNG byte order.
+ * The parameter is declared unsigned int, not png_uint_16,
+ * just to avoid potential problems on pre-ANSI C compilers.
+ */
+PNG_EXTERN void png_save_uint_16 PNGARG((png_bytep buf, unsigned int i));
+
+/* simple function to write the signature */
+PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
+
+/* write various chunks */
+
+/* Write the IHDR chunk, and update the png_struct with the necessary
+ * information.
+ */
+PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
+   png_uint_32 height,
+   int bit_depth, int color_type, int compression_method, int filter_method,
+   int interlace_method));
+
+PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,
+   png_uint_32 num_pal));
+
+PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
+   png_size_t length));
+
+PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
+
+#if defined(PNG_WRITE_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, png_fixed_point
+    file_gamma));
+#endif
+#endif
+
+#if defined(PNG_WRITE_sBIT_SUPPORTED)
+PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
+   int color_type));
+#endif
+
+#if defined(PNG_WRITE_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
+   double white_x, double white_y,
+   double red_x, double red_y, double green_x, double green_y,
+   double blue_x, double blue_y));
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
+   png_fixed_point int_white_x, png_fixed_point int_white_y,
+   png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
+   int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
+   png_fixed_point int_blue_y));
+#endif
+#endif
+
+#if defined(PNG_WRITE_sRGB_SUPPORTED)
+PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
+   int intent));
+#endif
+
+#if defined(PNG_WRITE_iCCP_SUPPORTED)
+PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
+   png_charp name, int compression_type,
+   png_charp profile, int proflen));
+   /* Note to maintainer: profile should be png_bytep */
+#endif
+
+#if defined(PNG_WRITE_sPLT_SUPPORTED)
+PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
+   png_sPLT_tp palette));
+#endif
+
+#if defined(PNG_WRITE_tRNS_SUPPORTED)
+PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
+   png_color_16p values, int number, int color_type));
+#endif
+
+#if defined(PNG_WRITE_bKGD_SUPPORTED)
+PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
+   png_color_16p values, int color_type));
+#endif
+
+#if defined(PNG_WRITE_hIST_SUPPORTED)
+PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
+   int num_hist));
+#endif
+
+#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
+    defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
+PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
+   png_charp key, png_charpp new_key));
+#endif
+
+#if defined(PNG_WRITE_tEXt_SUPPORTED)
+PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
+   png_charp text, png_size_t text_len));
+#endif
+
+#if defined(PNG_WRITE_zTXt_SUPPORTED)
+PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
+   png_charp text, png_size_t text_len, int compression));
+#endif
+
+#if defined(PNG_WRITE_iTXt_SUPPORTED)
+PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
+   int compression, png_charp key, png_charp lang, png_charp lang_key,
+   png_charp text));
+#endif
+
+#if defined(PNG_TEXT_SUPPORTED)  /* Added at version 1.0.14 and 1.2.4 */
+PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_textp text_ptr, int num_text));
+#endif
+
+#if defined(PNG_WRITE_oFFs_SUPPORTED)
+PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
+   png_int_32 x_offset, png_int_32 y_offset, int unit_type));
+#endif
+
+#if defined(PNG_WRITE_pCAL_SUPPORTED)
+PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
+   png_int_32 X0, png_int_32 X1, int type, int nparams,
+   png_charp units, png_charpp params));
+#endif
+
+#if defined(PNG_WRITE_pHYs_SUPPORTED)
+PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
+   png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
+   int unit_type));
+#endif
+
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
+   png_timep mod_time));
+#endif
+
+#if defined(PNG_WRITE_sCAL_SUPPORTED)
+#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
+PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr,
+   int unit, double width, double height));
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
+   int unit, png_charp width, png_charp height));
+#endif
+#endif
+#endif
+
+/* Called when finished processing a row of data */
+PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
+
+/* Internal use only.   Called before first row of data */
+PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr));
+#endif
+
+/* combine a row of data, dealing with alpha, etc. if requested */
+PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
+   int mask));
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+/* expand an interlaced row */
+/* OLD pre-1.0.9 interface:
+PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
+   png_bytep row, int pass, png_uint_32 transformations));
+ */
+PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr));
+#endif
+
+/* GRR TO DO (2.0 or whenever):  simplify other internal calling interfaces */
+
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+/* grab pixels out of a row for an interlaced pass */
+PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
+   png_bytep row, int pass));
+#endif
+
+/* unfilter a row */
+PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
+   png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter));
+
+/* Choose the best filter to use and filter the row data */
+PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
+   png_row_infop row_info));
+
+/* Write out the filtered row. */
+PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
+   png_bytep filtered_row));
+/* finish a row while reading, dealing with interlacing passes, etc. */
+PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
+
+/* initialize the row buffers, etc. */
+PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
+/* optional call to update the users info structure */
+PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+
+/* these are the functions that do the transformations */
+#if defined(PNG_READ_FILLER_SUPPORTED)
+PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
+   png_bytep row, png_uint_32 filler, png_uint_32 flags));
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
+PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
+   png_bytep row));
+#endif
+
+#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
+   png_bytep row));
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
+PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
+   png_bytep row));
+#endif
+
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
+   png_bytep row));
+#endif
+
+#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
+    defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
+   png_bytep row, png_uint_32 flags));
+#endif
+
+#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
+PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
+   row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
+   png_bytep row));
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED)
+PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED)
+PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
+   png_color_8p sig_bits));
+#endif
+
+#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
+PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
+   png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup));
+
+#  if defined(PNG_CORRECT_PALETTE_SUPPORTED)
+PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
+   png_colorp palette, int num_palette));
+#  endif
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
+PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
+#if defined(PNG_WRITE_PACK_SUPPORTED)
+PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
+   png_bytep row, png_uint_32 bit_depth));
+#endif
+
+#if defined(PNG_WRITE_SHIFT_SUPPORTED)
+PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
+   png_color_8p bit_depth));
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
+   png_color_16p trans_values, png_color_16p background,
+   png_color_16p background_1,
+   png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
+   png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
+   png_uint_16pp gamma_16_to_1, int gamma_shift));
+#else
+PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
+   png_color_16p trans_values, png_color_16p background));
+#endif
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
+   png_bytep gamma_table, png_uint_16pp gamma_16_table,
+   int gamma_shift));
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
+   png_bytep row, png_colorp palette, png_bytep trans, int num_trans));
+PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
+   png_bytep row, png_color_16p trans_value));
+#endif
+
+/* The following decodes the appropriate chunks, and does error correction,
+ * then calls the appropriate callback for the chunk if it is valid.
+ */
+
+/* decode the IHDR chunk */
+PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+
+#if defined(PNG_READ_bKGD_SUPPORTED)
+PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_cHRM_SUPPORTED)
+PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_gAMA_SUPPORTED)
+PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_hIST_SUPPORTED)
+PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_iCCP_SUPPORTED)
+extern void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif /* PNG_READ_iCCP_SUPPORTED */
+
+#if defined(PNG_READ_iTXt_SUPPORTED)
+PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_oFFs_SUPPORTED)
+PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_pCAL_SUPPORTED)
+PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_pHYs_SUPPORTED)
+PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_sBIT_SUPPORTED)
+PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_sCAL_SUPPORTED)
+PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_sPLT_SUPPORTED)
+extern void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif /* PNG_READ_sPLT_SUPPORTED */
+
+#if defined(PNG_READ_sRGB_SUPPORTED)
+PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_tEXt_SUPPORTED)
+PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_tIME_SUPPORTED)
+PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_tRNS_SUPPORTED)
+PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+#if defined(PNG_READ_zTXt_SUPPORTED)
+PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 length));
+#endif
+
+PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_32 length));
+
+PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
+   png_bytep chunk_name));
+
+/* handle the transformations for reading and writing */
+PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
+
+PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
+   png_uint_32 length));
+PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
+   png_bytep buffer, png_size_t buffer_length));
+PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
+   png_bytep buffer, png_size_t buffer_length));
+PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
+PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
+#if defined(PNG_READ_tEXt_SUPPORTED)
+PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
+   png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
+#endif
+
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
+   png_bytep row));
+PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
+   png_bytep row));
+#endif
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+/* png.c */ /* PRIVATE */
+PNG_EXTERN void png_init_mmx_flags PNGARG((png_structp png_ptr));
+#endif
+/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
+
+#endif /* PNG_INTERNAL */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PNG_VERSION_INFO_ONLY */
+/* do not put anything past this line */
+#endif /* PNG_H */
diff --git a/gs/libpng/pngbar.jpg b/gs/libpng/pngbar.jpg
new file mode 100644
index 000000000..70ba8d817
--- /dev/null
+++ b/gs/libpng/pngbar.jpg
diff --git a/gs/libpng/pngbar.png b/gs/libpng/pngbar.png
new file mode 100644
index 000000000..49798c8ed
--- /dev/null
+++ b/gs/libpng/pngbar.png
diff --git a/gs/libpng/pngconf.h b/gs/libpng/pngconf.h
new file mode 100644
index 000000000..ba5083845
--- /dev/null
+++ b/gs/libpng/pngconf.h
@@ -0,0 +1,1437 @@
+
+/* pngconf.h - machine configurable file for libpng
+ *
+ * libpng version 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+/* Any machine specific code is near the front of this file, so if you
+ * are configuring libpng for a machine, you may want to read the section
+ * starting here down to where it starts to typedef png_color, png_text,
+ * and png_info.
+ */
+
+#ifndef PNGCONF_H
+#define PNGCONF_H
+
+#define PNG_1_2_X
+
+/* 
+ * PNG_USER_CONFIG has to be defined on the compiler command line. This
+ * includes the resource compiler for Windows DLL configurations.
+ */
+#ifdef PNG_USER_CONFIG
+#include "pngusr.h"
+#endif
+
+/*
+ * Added at libpng-1.2.8
+ *  
+ * If you create a private DLL you need to define in "pngusr.h" the followings:
+ * #define PNG_USER_PRIVATEBUILD <Describes by whom and why this version of
+ *        the DLL was built>
+ *  e.g. #define PNG_USER_PRIVATEBUILD "Build by MyCompany for xyz reasons."
+ * #define PNG_USER_DLLFNAME_POSTFIX <two-letter postfix that serve to
+ *        distinguish your DLL from those of the official release. These
+ *        correspond to the trailing letters that come after the version
+ *        number and must match your private DLL name>
+ *  e.g. // private DLL "libpng13gx.dll"
+ *       #define PNG_USER_DLLFNAME_POSTFIX "gx"
+ * 
+ * The following macros are also at your disposal if you want to complete the 
+ * DLL VERSIONINFO structure.
+ * - PNG_USER_VERSIONINFO_COMMENTS
+ * - PNG_USER_VERSIONINFO_COMPANYNAME
+ * - PNG_USER_VERSIONINFO_LEGALTRADEMARKS
+ */
+
+#ifdef __STDC__
+#ifdef SPECIALBUILD
+#  pragma message("PNG_LIBPNG_SPECIALBUILD (and deprecated SPECIALBUILD)\
+ are now LIBPNG reserved macros. Use PNG_USER_PRIVATEBUILD instead.")
+#endif
+
+#ifdef PRIVATEBUILD
+# pragma message("PRIVATEBUILD is deprecated. Use\
+ PNG_USER_PRIVATEBUILD instead.")
+# define PNG_USER_PRIVATEBUILD PRIVATEBUILD
+#endif
+#endif /* __STDC__ */
+
+#ifndef PNG_VERSION_INFO_ONLY
+
+/* End of material added to libpng-1.2.8 */
+
+/* This is the size of the compression buffer, and thus the size of
+ * an IDAT chunk.  Make this whatever size you feel is best for your
+ * machine.  One of these will be allocated per png_struct.  When this
+ * is full, it writes the data to the disk, and does some other
+ * calculations.  Making this an extremely small size will slow
+ * the library down, but you may want to experiment to determine
+ * where it becomes significant, if you are concerned with memory
+ * usage.  Note that zlib allocates at least 32Kb also.  For readers,
+ * this describes the size of the buffer available to read the data in.
+ * Unless this gets smaller than the size of a row (compressed),
+ * it should not make much difference how big this is.
+ */
+
+#ifndef PNG_ZBUF_SIZE
+#  define PNG_ZBUF_SIZE 8192
+#endif
+
+/* Enable if you want a write-only libpng */
+
+#ifndef PNG_NO_READ_SUPPORTED
+#  define PNG_READ_SUPPORTED
+#endif
+
+/* Enable if you want a read-only libpng */
+
+#ifndef PNG_NO_WRITE_SUPPORTED
+#  define PNG_WRITE_SUPPORTED
+#endif
+
+/* Enabled by default in 1.2.0.  You can disable this if you don't need to
+   support PNGs that are embedded in MNG datastreams */
+#if !defined(PNG_1_0_X) && !defined(PNG_NO_MNG_FEATURES)
+#  ifndef PNG_MNG_FEATURES_SUPPORTED
+#    define PNG_MNG_FEATURES_SUPPORTED
+#  endif
+#endif
+
+#ifndef PNG_NO_FLOATING_POINT_SUPPORTED
+#  ifndef PNG_FLOATING_POINT_SUPPORTED
+#    define PNG_FLOATING_POINT_SUPPORTED
+#  endif
+#endif
+
+/* If you are running on a machine where you cannot allocate more
+ * than 64K of memory at once, uncomment this.  While libpng will not
+ * normally need that much memory in a chunk (unless you load up a very
+ * large file), zlib needs to know how big of a chunk it can use, and
+ * libpng thus makes sure to check any memory allocation to verify it
+ * will fit into memory.
+#define PNG_MAX_MALLOC_64K
+ */
+#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
+#  define PNG_MAX_MALLOC_64K
+#endif
+
+/* Special munging to support doing things the 'cygwin' way:
+ * 'Normal' png-on-win32 defines/defaults:
+ *   PNG_BUILD_DLL -- building dll
+ *   PNG_USE_DLL   -- building an application, linking to dll
+ *   (no define)   -- building static library, or building an
+ *                    application and linking to the static lib
+ * 'Cygwin' defines/defaults:
+ *   PNG_BUILD_DLL -- (ignored) building the dll
+ *   (no define)   -- (ignored) building an application, linking to the dll
+ *   PNG_STATIC    -- (ignored) building the static lib, or building an 
+ *                    application that links to the static lib.
+ *   ALL_STATIC    -- (ignored) building various static libs, or building an 
+ *                    application that links to the static libs.
+ * Thus,
+ * a cygwin user should define either PNG_BUILD_DLL or PNG_STATIC, and
+ * this bit of #ifdefs will define the 'correct' config variables based on
+ * that. If a cygwin user *wants* to define 'PNG_USE_DLL' that's okay, but
+ * unnecessary.
+ *
+ * Also, the precedence order is:
+ *   ALL_STATIC (since we can't #undef something outside our namespace)
+ *   PNG_BUILD_DLL
+ *   PNG_STATIC
+ *   (nothing) == PNG_USE_DLL
+ * 
+ * CYGWIN (2002-01-20): The preceding is now obsolete. With the advent
+ *   of auto-import in binutils, we no longer need to worry about 
+ *   __declspec(dllexport) / __declspec(dllimport) and friends.  Therefore,
+ *   we don't need to worry about PNG_STATIC or ALL_STATIC when it comes
+ *   to __declspec() stuff.  However, we DO need to worry about 
+ *   PNG_BUILD_DLL and PNG_STATIC because those change some defaults
+ *   such as CONSOLE_IO and whether GLOBAL_ARRAYS are allowed.
+ */
+#if defined(__CYGWIN__)
+#  if defined(ALL_STATIC)
+#    if defined(PNG_BUILD_DLL)
+#      undef PNG_BUILD_DLL
+#    endif
+#    if defined(PNG_USE_DLL)
+#      undef PNG_USE_DLL
+#    endif
+#    if defined(PNG_DLL)
+#      undef PNG_DLL
+#    endif
+#    if !defined(PNG_STATIC)
+#      define PNG_STATIC
+#    endif
+#  else
+#    if defined (PNG_BUILD_DLL)
+#      if defined(PNG_STATIC)
+#        undef PNG_STATIC
+#      endif
+#      if defined(PNG_USE_DLL)
+#        undef PNG_USE_DLL
+#      endif
+#      if !defined(PNG_DLL)
+#        define PNG_DLL
+#      endif
+#    else
+#      if defined(PNG_STATIC)
+#        if defined(PNG_USE_DLL)
+#          undef PNG_USE_DLL
+#        endif
+#        if defined(PNG_DLL)
+#          undef PNG_DLL
+#        endif
+#      else
+#        if !defined(PNG_USE_DLL)
+#          define PNG_USE_DLL
+#        endif
+#        if !defined(PNG_DLL)
+#          define PNG_DLL
+#        endif
+#      endif  
+#    endif  
+#  endif
+#endif
+
+/* This protects us against compilers that run on a windowing system
+ * and thus don't have or would rather us not use the stdio types:
+ * stdin, stdout, and stderr.  The only one currently used is stderr
+ * in png_error() and png_warning().  #defining PNG_NO_CONSOLE_IO will
+ * prevent these from being compiled and used. #defining PNG_NO_STDIO
+ * will also prevent these, plus will prevent the entire set of stdio
+ * macros and functions (FILE *, printf, etc.) from being compiled and used,
+ * unless (PNG_DEBUG > 0) has been #defined.
+ *
+ * #define PNG_NO_CONSOLE_IO
+ * #define PNG_NO_STDIO
+ */
+
+#if defined(_WIN32_WCE)
+#  include <windows.h>
+   /* Console I/O functions are not supported on WindowsCE */
+#  define PNG_NO_CONSOLE_IO
+#  ifdef PNG_DEBUG
+#    undef PNG_DEBUG
+#  endif
+#endif
+
+#ifdef PNG_BUILD_DLL
+#  ifndef PNG_CONSOLE_IO_SUPPORTED
+#    ifndef PNG_NO_CONSOLE_IO
+#      define PNG_NO_CONSOLE_IO
+#    endif
+#  endif
+#endif
+
+#  ifdef PNG_NO_STDIO
+#    ifndef PNG_NO_CONSOLE_IO
+#      define PNG_NO_CONSOLE_IO
+#    endif
+#    ifdef PNG_DEBUG
+#      if (PNG_DEBUG > 0)
+#        include <stdio.h>
+#      endif
+#    endif
+#  else
+#    if !defined(_WIN32_WCE)
+/* "stdio.h" functions are not supported on WindowsCE */
+#      include <stdio.h>
+#    endif
+#  endif
+
+/* This macro protects us against machines that don't have function
+ * prototypes (ie K&R style headers).  If your compiler does not handle
+ * function prototypes, define this macro and use the included ansi2knr.
+ * I've always been able to use _NO_PROTO as the indicator, but you may
+ * need to drag the empty declaration out in front of here, or change the
+ * ifdef to suit your own needs.
+ */
+#ifndef PNGARG
+
+#ifdef OF /* zlib prototype munger */
+#  define PNGARG(arglist) OF(arglist)
+#else
+
+#ifdef _NO_PROTO
+#  define PNGARG(arglist) ()
+#  ifndef PNG_TYPECAST_NULL
+#     define PNG_TYPECAST_NULL
+#  endif
+#else
+#  define PNGARG(arglist) arglist
+#endif /* _NO_PROTO */
+
+#endif /* OF */
+
+#endif /* PNGARG */
+
+/* Try to determine if we are compiling on a Mac.  Note that testing for
+ * just __MWERKS__ is not good enough, because the Codewarrior is now used
+ * on non-Mac platforms.
+ */
+#ifndef MACOS
+#  if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
+      defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
+#    define MACOS
+#  endif
+#endif
+
+/* enough people need this for various reasons to include it here */
+#if !defined(MACOS) && !defined(RISCOS) && !defined(_WIN32_WCE)
+#  include <sys/types.h>
+#endif
+
+#if !defined(PNG_SETJMP_NOT_SUPPORTED) && !defined(PNG_NO_SETJMP_SUPPORTED)
+#  define PNG_SETJMP_SUPPORTED
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+/* This is an attempt to force a single setjmp behaviour on Linux.  If
+ * the X config stuff didn't define _BSD_SOURCE we wouldn't need this.
+ */
+
+#  ifdef __linux__
+#    ifdef _BSD_SOURCE
+#      define PNG_SAVE_BSD_SOURCE
+#      undef _BSD_SOURCE
+#    endif
+#    ifdef _SETJMP_H
+     /* If you encounter a compiler error here, see the explanation
+      * near the end of INSTALL.
+      */
+         __png.h__ already includes setjmp.h;
+         __dont__ include it again.;
+#    endif
+#  endif /* __linux__ */
+
+   /* include setjmp.h for error handling */
+#  include <setjmp.h>
+
+#  ifdef __linux__
+#    ifdef PNG_SAVE_BSD_SOURCE
+#      define _BSD_SOURCE
+#      undef PNG_SAVE_BSD_SOURCE
+#    endif
+#  endif /* __linux__ */
+#endif /* PNG_SETJMP_SUPPORTED */
+
+#ifdef BSD
+#  include <strings.h>
+#else
+#  include <string.h>
+#endif
+
+/* Other defines for things like memory and the like can go here.  */
+#ifdef PNG_INTERNAL
+
+#include <stdlib.h>
+
+/* The functions exported by PNG_EXTERN are PNG_INTERNAL functions, which
+ * aren't usually used outside the library (as far as I know), so it is
+ * debatable if they should be exported at all.  In the future, when it is
+ * possible to have run-time registry of chunk-handling functions, some of
+ * these will be made available again.
+#define PNG_EXTERN extern
+ */
+#define PNG_EXTERN
+
+/* Other defines specific to compilers can go here.  Try to keep
+ * them inside an appropriate ifdef/endif pair for portability.
+ */
+
+#if defined(PNG_FLOATING_POINT_SUPPORTED)
+#  if defined(MACOS)
+     /* We need to check that <math.h> hasn't already been included earlier
+      * as it seems it doesn't agree with <fp.h>, yet we should really use
+      * <fp.h> if possible.
+      */
+#    if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
+#      include <fp.h>
+#    endif
+#  else
+#    include <math.h>
+#  endif
+#  if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
+     /* Amiga SAS/C: We must include builtin FPU functions when compiling using
+      * MATH=68881
+      */
+#    include <m68881.h>
+#  endif
+#endif
+
+/* Codewarrior on NT has linking problems without this. */
+#if (defined(__MWERKS__) && defined(WIN32)) || defined(__STDC__)
+#  define PNG_ALWAYS_EXTERN
+#endif
+
+/* This provides the non-ANSI (far) memory allocation routines. */
+#if defined(__TURBOC__) && defined(__MSDOS__)
+#  include <mem.h>
+#  include <alloc.h>
+#endif
+
+/* I have no idea why is this necessary... */
+#if defined(_MSC_VER) && (defined(WIN32) || defined(_Windows) || \
+    defined(_WINDOWS) || defined(_WIN32) || defined(__WIN32__))
+#  include <malloc.h>
+#endif
+
+/* This controls how fine the dithering gets.  As this allocates
+ * a largish chunk of memory (32K), those who are not as concerned
+ * with dithering quality can decrease some or all of these.
+ */
+#ifndef PNG_DITHER_RED_BITS
+#  define PNG_DITHER_RED_BITS 5
+#endif
+#ifndef PNG_DITHER_GREEN_BITS
+#  define PNG_DITHER_GREEN_BITS 5
+#endif
+#ifndef PNG_DITHER_BLUE_BITS
+#  define PNG_DITHER_BLUE_BITS 5
+#endif
+
+/* This controls how fine the gamma correction becomes when you
+ * are only interested in 8 bits anyway.  Increasing this value
+ * results in more memory being used, and more pow() functions
+ * being called to fill in the gamma tables.  Don't set this value
+ * less then 8, and even that may not work (I haven't tested it).
+ */
+
+#ifndef PNG_MAX_GAMMA_8
+#  define PNG_MAX_GAMMA_8 11
+#endif
+
+/* This controls how much a difference in gamma we can tolerate before
+ * we actually start doing gamma conversion.
+ */
+#ifndef PNG_GAMMA_THRESHOLD
+#  define PNG_GAMMA_THRESHOLD 0.05
+#endif
+
+#endif /* PNG_INTERNAL */
+
+/* The following uses const char * instead of char * for error
+ * and warning message functions, so some compilers won't complain.
+ * If you do not want to use const, define PNG_NO_CONST here.
+ */
+
+#ifndef PNG_NO_CONST
+#  define PNG_CONST const
+#else
+#  define PNG_CONST
+#endif
+
+/* The following defines give you the ability to remove code from the
+ * library that you will not be using.  I wish I could figure out how to
+ * automate this, but I can't do that without making it seriously hard
+ * on the users.  So if you are not using an ability, change the #define
+ * to and #undef, and that part of the library will not be compiled.  If
+ * your linker can't find a function, you may want to make sure the
+ * ability is defined here.  Some of these depend upon some others being
+ * defined.  I haven't figured out all the interactions here, so you may
+ * have to experiment awhile to get everything to compile.  If you are
+ * creating or using a shared library, you probably shouldn't touch this,
+ * as it will affect the size of the structures, and this will cause bad
+ * things to happen if the library and/or application ever change.
+ */
+
+/* Any features you will not be using can be undef'ed here */
+
+/* GR-P, 0.96a: Set "*TRANSFORMS_SUPPORTED as default but allow user
+ * to turn it off with "*TRANSFORMS_NOT_SUPPORTED" or *PNG_NO_*_TRANSFORMS
+ * on the compile line, then pick and choose which ones to define without
+ * having to edit this file. It is safe to use the *TRANSFORMS_NOT_SUPPORTED
+ * if you only want to have a png-compliant reader/writer but don't need
+ * any of the extra transformations.  This saves about 80 kbytes in a
+ * typical installation of the library. (PNG_NO_* form added in version
+ * 1.0.1c, for consistency)
+ */
+
+/* The size of the png_text structure changed in libpng-1.0.6 when
+ * iTXt is supported.  It is turned off by default, to support old apps
+ * that malloc the png_text structure instead of calling png_set_text()
+ * and letting libpng malloc it.  It will be turned on by default in
+ * libpng-1.3.0.
+ */
+
+#ifndef PNG_iTXt_SUPPORTED
+#  if !defined(PNG_READ_iTXt_SUPPORTED) && !defined(PNG_NO_READ_iTXt)
+#    define PNG_NO_READ_iTXt
+#  endif
+#  if !defined(PNG_WRITE_iTXt_SUPPORTED) && !defined(PNG_NO_WRITE_iTXt)
+#    define PNG_NO_WRITE_iTXt
+#  endif
+#endif
+
+/* The following support, added after version 1.0.0, can be turned off here en
+ * masse by defining PNG_LEGACY_SUPPORTED in case you need binary compatibility
+ * with old applications that require the length of png_struct and png_info
+ * to remain unchanged.
+ */
+
+#ifdef PNG_LEGACY_SUPPORTED
+#  define PNG_NO_FREE_ME
+#  define PNG_NO_READ_UNKNOWN_CHUNKS
+#  define PNG_NO_WRITE_UNKNOWN_CHUNKS
+#  define PNG_NO_READ_USER_CHUNKS
+#  define PNG_NO_READ_iCCP
+#  define PNG_NO_WRITE_iCCP
+#  define PNG_NO_READ_iTXt
+#  define PNG_NO_WRITE_iTXt
+#  define PNG_NO_READ_sCAL
+#  define PNG_NO_WRITE_sCAL
+#  define PNG_NO_READ_sPLT
+#  define PNG_NO_WRITE_sPLT
+#  define PNG_NO_INFO_IMAGE
+#  define PNG_NO_READ_RGB_TO_GRAY
+#  define PNG_NO_READ_USER_TRANSFORM
+#  define PNG_NO_WRITE_USER_TRANSFORM
+#  define PNG_NO_USER_MEM
+#  define PNG_NO_READ_EMPTY_PLTE
+#  define PNG_NO_MNG_FEATURES
+#  define PNG_NO_FIXED_POINT_SUPPORTED
+#endif
+
+/* Ignore attempt to turn off both floating and fixed point support */
+#if !defined(PNG_FLOATING_POINT_SUPPORTED) || \
+    !defined(PNG_NO_FIXED_POINT_SUPPORTED)
+#  define PNG_FIXED_POINT_SUPPORTED
+#endif
+
+#ifndef PNG_NO_FREE_ME
+#  define PNG_FREE_ME_SUPPORTED
+#endif
+
+#if defined(PNG_READ_SUPPORTED)
+
+#if !defined(PNG_READ_TRANSFORMS_NOT_SUPPORTED) && \
+      !defined(PNG_NO_READ_TRANSFORMS)
+#  define PNG_READ_TRANSFORMS_SUPPORTED
+#endif
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+#  ifndef PNG_NO_READ_EXPAND
+#    define PNG_READ_EXPAND_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_SHIFT
+#    define PNG_READ_SHIFT_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_PACK
+#    define PNG_READ_PACK_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_BGR
+#    define PNG_READ_BGR_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_SWAP
+#    define PNG_READ_SWAP_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_PACKSWAP
+#    define PNG_READ_PACKSWAP_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_INVERT
+#    define PNG_READ_INVERT_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_DITHER
+#    define PNG_READ_DITHER_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_BACKGROUND
+#    define PNG_READ_BACKGROUND_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_16_TO_8
+#    define PNG_READ_16_TO_8_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_FILLER
+#    define PNG_READ_FILLER_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_GAMMA
+#    define PNG_READ_GAMMA_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_GRAY_TO_RGB
+#    define PNG_READ_GRAY_TO_RGB_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_SWAP_ALPHA
+#    define PNG_READ_SWAP_ALPHA_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_INVERT_ALPHA
+#    define PNG_READ_INVERT_ALPHA_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_STRIP_ALPHA
+#    define PNG_READ_STRIP_ALPHA_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_USER_TRANSFORM
+#    define PNG_READ_USER_TRANSFORM_SUPPORTED
+#  endif
+#  ifndef PNG_NO_READ_RGB_TO_GRAY
+#    define PNG_READ_RGB_TO_GRAY_SUPPORTED
+#  endif
+#endif /* PNG_READ_TRANSFORMS_SUPPORTED */
+
+#if !defined(PNG_NO_PROGRESSIVE_READ) && \
+ !defined(PNG_PROGRESSIVE_READ_NOT_SUPPORTED)  /* if you don't do progressive */
+#  define PNG_PROGRESSIVE_READ_SUPPORTED     /* reading.  This is not talking */
+#endif                               /* about interlacing capability!  You'll */
+              /* still have interlacing unless you change the following line: */
+
+#define PNG_READ_INTERLACING_SUPPORTED /* required for PNG-compliant decoders */
+
+#ifndef PNG_NO_READ_COMPOSITE_NODIV
+#  ifndef PNG_NO_READ_COMPOSITED_NODIV  /* libpng-1.0.x misspelling */
+#    define PNG_READ_COMPOSITE_NODIV_SUPPORTED   /* well tested on Intel, SGI */
+#  endif
+#endif
+
+/* Deprecated, will be removed from version 2.0.0.
+   Use PNG_MNG_FEATURES_SUPPORTED instead. */
+#ifndef PNG_NO_READ_EMPTY_PLTE
+#  define PNG_READ_EMPTY_PLTE_SUPPORTED
+#endif
+
+#endif /* PNG_READ_SUPPORTED */
+
+#if defined(PNG_WRITE_SUPPORTED)
+
+# if !defined(PNG_WRITE_TRANSFORMS_NOT_SUPPORTED) && \
+    !defined(PNG_NO_WRITE_TRANSFORMS)
+#  define PNG_WRITE_TRANSFORMS_SUPPORTED
+#endif
+
+#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
+#  ifndef PNG_NO_WRITE_SHIFT
+#    define PNG_WRITE_SHIFT_SUPPORTED
+#  endif
+#  ifndef PNG_NO_WRITE_PACK
+#    define PNG_WRITE_PACK_SUPPORTED
+#  endif
+#  ifndef PNG_NO_WRITE_BGR
+#    define PNG_WRITE_BGR_SUPPORTED
+#  endif
+#  ifndef PNG_NO_WRITE_SWAP
+#    define PNG_WRITE_SWAP_SUPPORTED
+#  endif
+#  ifndef PNG_NO_WRITE_PACKSWAP
+#    define PNG_WRITE_PACKSWAP_SUPPORTED
+#  endif
+#  ifndef PNG_NO_WRITE_INVERT
+#    define PNG_WRITE_INVERT_SUPPORTED
+#  endif
+#  ifndef PNG_NO_WRITE_FILLER
+#    define PNG_WRITE_FILLER_SUPPORTED   /* same as WRITE_STRIP_ALPHA */
+#  endif
+#  ifndef PNG_NO_WRITE_SWAP_ALPHA
+#    define PNG_WRITE_SWAP_ALPHA_SUPPORTED
+#  endif
+#  ifndef PNG_NO_WRITE_INVERT_ALPHA
+#    define PNG_WRITE_INVERT_ALPHA_SUPPORTED
+#  endif
+#  ifndef PNG_NO_WRITE_USER_TRANSFORM
+#    define PNG_WRITE_USER_TRANSFORM_SUPPORTED
+#  endif
+#endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */
+
+#define PNG_WRITE_INTERLACING_SUPPORTED  /* not required for PNG-compliant
+                                            encoders, but can cause trouble
+                                            if left undefined */
+
+#if !defined(PNG_NO_WRITE_WEIGHTED_FILTER) && \
+     defined(PNG_FLOATING_POINT_SUPPORTED)
+#  define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
+#endif
+
+#ifndef PNG_NO_WRITE_FLUSH
+#  define PNG_WRITE_FLUSH_SUPPORTED
+#endif
+
+/* Deprecated, see PNG_MNG_FEATURES_SUPPORTED, above */
+#ifndef PNG_NO_WRITE_EMPTY_PLTE
+#  define PNG_WRITE_EMPTY_PLTE_SUPPORTED
+#endif
+
+#endif /* PNG_WRITE_SUPPORTED */
+
+#ifndef PNG_1_0_X
+#  ifndef PNG_NO_ERROR_NUMBERS
+#    define PNG_ERROR_NUMBERS_SUPPORTED
+#  endif
+#endif /* PNG_1_0_X */
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+#  ifndef PNG_NO_USER_TRANSFORM_PTR
+#    define PNG_USER_TRANSFORM_PTR_SUPPORTED
+#  endif
+#endif
+
+#ifndef PNG_NO_STDIO
+#  define PNG_TIME_RFC1123_SUPPORTED
+#endif
+
+/* This adds extra functions in pngget.c for accessing data from the
+ * info pointer (added in version 0.99)
+ * png_get_image_width()
+ * png_get_image_height()
+ * png_get_bit_depth()
+ * png_get_color_type()
+ * png_get_compression_type()
+ * png_get_filter_type()
+ * png_get_interlace_type()
+ * png_get_pixel_aspect_ratio()
+ * png_get_pixels_per_meter()
+ * png_get_x_offset_pixels()
+ * png_get_y_offset_pixels()
+ * png_get_x_offset_microns()
+ * png_get_y_offset_microns()
+ */
+#if !defined(PNG_NO_EASY_ACCESS) && !defined(PNG_EASY_ACCESS_SUPPORTED)
+#  define PNG_EASY_ACCESS_SUPPORTED
+#endif
+
+/* PNG_ASSEMBLER_CODE was enabled by default in version 1.2.0 
+   even when PNG_USE_PNGVCRD or PNG_USE_PNGGCCRD is not defined */
+#if defined(PNG_READ_SUPPORTED) && !defined(PNG_NO_ASSEMBLER_CODE)
+#  ifndef PNG_ASSEMBLER_CODE_SUPPORTED
+#    define PNG_ASSEMBLER_CODE_SUPPORTED
+#  endif
+#  if !defined(PNG_MMX_CODE_SUPPORTED) && !defined(PNG_NO_MMX_CODE)
+#    define PNG_MMX_CODE_SUPPORTED
+#  endif
+#endif
+
+/* If you are sure that you don't need thread safety and you are compiling
+   with PNG_USE_PNGCCRD for an MMX application, you can define this for
+   faster execution.  See pnggccrd.c.
+#define PNG_THREAD_UNSAFE_OK
+*/
+
+#if !defined(PNG_1_0_X)
+#if !defined(PNG_NO_USER_MEM) && !defined(PNG_USER_MEM_SUPPORTED)
+#  define PNG_USER_MEM_SUPPORTED
+#endif
+#endif /* PNG_1_0_X */
+
+/* Added at libpng-1.2.6 */
+#if !defined(PNG_1_0_X)
+#ifndef PNG_SET_USER_LIMITS_SUPPORTED
+#if !defined(PNG_NO_SET_USER_LIMITS) && !defined(PNG_SET_USER_LIMITS_SUPPORTED)
+#  define PNG_SET_USER_LIMITS_SUPPORTED
+#endif
+#endif
+#endif /* PNG_1_0_X */
+
+/* Added at libpng-1.0.16 and 1.2.6.  To accept all valid PNGS no matter
+ * how large, set these limits to 0x7fffffffL
+ */
+#ifndef PNG_USER_WIDTH_MAX
+#  define PNG_USER_WIDTH_MAX 1000000L
+#endif
+#ifndef PNG_USER_HEIGHT_MAX
+#  define PNG_USER_HEIGHT_MAX 1000000L
+#endif
+
+/* These are currently experimental features, define them if you want */
+
+/* very little testing */
+/*
+#ifdef PNG_READ_SUPPORTED
+#  ifndef PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
+#    define PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
+#  endif
+#endif
+*/
+
+/* This is only for PowerPC big-endian and 680x0 systems */
+/* some testing */
+/*
+#ifndef PNG_READ_BIG_ENDIAN_SUPPORTED
+#  define PNG_READ_BIG_ENDIAN_SUPPORTED
+#endif
+*/
+
+/* Buggy compilers (e.g., gcc 2.7.2.2) need this */
+/*
+#define PNG_NO_POINTER_INDEXING
+*/
+
+/* These functions are turned off by default, as they will be phased out. */
+/*
+#define  PNG_USELESS_TESTS_SUPPORTED
+#define  PNG_CORRECT_PALETTE_SUPPORTED
+*/
+
+/* Any chunks you are not interested in, you can undef here.  The
+ * ones that allocate memory may be expecially important (hIST,
+ * tEXt, zTXt, tRNS, pCAL).  Others will just save time and make png_info
+ * a bit smaller.
+ */
+
+#if defined(PNG_READ_SUPPORTED) && \
+    !defined(PNG_READ_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \
+    !defined(PNG_NO_READ_ANCILLARY_CHUNKS)
+#  define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
+#endif
+
+#if defined(PNG_WRITE_SUPPORTED) && \
+    !defined(PNG_WRITE_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \
+    !defined(PNG_NO_WRITE_ANCILLARY_CHUNKS)
+#  define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
+#endif
+
+#ifdef PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
+
+#ifdef PNG_NO_READ_TEXT
+#  define PNG_NO_READ_iTXt
+#  define PNG_NO_READ_tEXt
+#  define PNG_NO_READ_zTXt
+#endif
+#ifndef PNG_NO_READ_bKGD
+#  define PNG_READ_bKGD_SUPPORTED
+#  define PNG_bKGD_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_cHRM
+#  define PNG_READ_cHRM_SUPPORTED
+#  define PNG_cHRM_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_gAMA
+#  define PNG_READ_gAMA_SUPPORTED
+#  define PNG_gAMA_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_hIST
+#  define PNG_READ_hIST_SUPPORTED
+#  define PNG_hIST_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_iCCP
+#  define PNG_READ_iCCP_SUPPORTED
+#  define PNG_iCCP_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_iTXt
+#  ifndef PNG_READ_iTXt_SUPPORTED
+#    define PNG_READ_iTXt_SUPPORTED
+#  endif
+#  ifndef PNG_iTXt_SUPPORTED
+#    define PNG_iTXt_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_READ_oFFs
+#  define PNG_READ_oFFs_SUPPORTED
+#  define PNG_oFFs_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_pCAL
+#  define PNG_READ_pCAL_SUPPORTED
+#  define PNG_pCAL_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_sCAL
+#  define PNG_READ_sCAL_SUPPORTED
+#  define PNG_sCAL_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_pHYs
+#  define PNG_READ_pHYs_SUPPORTED
+#  define PNG_pHYs_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_sBIT
+#  define PNG_READ_sBIT_SUPPORTED
+#  define PNG_sBIT_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_sPLT
+#  define PNG_READ_sPLT_SUPPORTED
+#  define PNG_sPLT_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_sRGB
+#  define PNG_READ_sRGB_SUPPORTED
+#  define PNG_sRGB_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_tEXt
+#  define PNG_READ_tEXt_SUPPORTED
+#  define PNG_tEXt_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_tIME
+#  define PNG_READ_tIME_SUPPORTED
+#  define PNG_tIME_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_tRNS
+#  define PNG_READ_tRNS_SUPPORTED
+#  define PNG_tRNS_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_zTXt
+#  define PNG_READ_zTXt_SUPPORTED
+#  define PNG_zTXt_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_UNKNOWN_CHUNKS
+#  define PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
+#  ifndef PNG_UNKNOWN_CHUNKS_SUPPORTED
+#    define PNG_UNKNOWN_CHUNKS_SUPPORTED
+#  endif
+#  ifndef PNG_NO_HANDLE_AS_UNKNOWN
+#    define PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+#  endif
+#endif
+#if !defined(PNG_NO_READ_USER_CHUNKS) && \
+     defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+#  define PNG_READ_USER_CHUNKS_SUPPORTED
+#  define PNG_USER_CHUNKS_SUPPORTED
+#  ifdef PNG_NO_READ_UNKNOWN_CHUNKS
+#    undef PNG_NO_READ_UNKNOWN_CHUNKS
+#  endif
+#  ifdef PNG_NO_HANDLE_AS_UNKNOWN
+#    undef PNG_NO_HANDLE_AS_UNKNOWN
+#  endif
+#endif
+#ifndef PNG_NO_READ_OPT_PLTE
+#  define PNG_READ_OPT_PLTE_SUPPORTED /* only affects support of the */
+#endif                      /* optional PLTE chunk in RGB and RGBA images */
+#if defined(PNG_READ_iTXt_SUPPORTED) || defined(PNG_READ_tEXt_SUPPORTED) || \
+    defined(PNG_READ_zTXt_SUPPORTED)
+#  define PNG_READ_TEXT_SUPPORTED
+#  define PNG_TEXT_SUPPORTED
+#endif
+
+#endif /* PNG_READ_ANCILLARY_CHUNKS_SUPPORTED */
+
+#ifdef PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
+
+#ifdef PNG_NO_WRITE_TEXT
+#  define PNG_NO_WRITE_iTXt
+#  define PNG_NO_WRITE_tEXt
+#  define PNG_NO_WRITE_zTXt
+#endif
+#ifndef PNG_NO_WRITE_bKGD
+#  define PNG_WRITE_bKGD_SUPPORTED
+#  ifndef PNG_bKGD_SUPPORTED
+#    define PNG_bKGD_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_cHRM
+#  define PNG_WRITE_cHRM_SUPPORTED
+#  ifndef PNG_cHRM_SUPPORTED
+#    define PNG_cHRM_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_gAMA
+#  define PNG_WRITE_gAMA_SUPPORTED
+#  ifndef PNG_gAMA_SUPPORTED
+#    define PNG_gAMA_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_hIST
+#  define PNG_WRITE_hIST_SUPPORTED
+#  ifndef PNG_hIST_SUPPORTED
+#    define PNG_hIST_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_iCCP
+#  define PNG_WRITE_iCCP_SUPPORTED
+#  ifndef PNG_iCCP_SUPPORTED
+#    define PNG_iCCP_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_iTXt
+#  ifndef PNG_WRITE_iTXt_SUPPORTED
+#    define PNG_WRITE_iTXt_SUPPORTED
+#  endif
+#  ifndef PNG_iTXt_SUPPORTED
+#    define PNG_iTXt_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_oFFs
+#  define PNG_WRITE_oFFs_SUPPORTED
+#  ifndef PNG_oFFs_SUPPORTED
+#    define PNG_oFFs_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_pCAL
+#  define PNG_WRITE_pCAL_SUPPORTED
+#  ifndef PNG_pCAL_SUPPORTED
+#    define PNG_pCAL_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_sCAL
+#  define PNG_WRITE_sCAL_SUPPORTED
+#  ifndef PNG_sCAL_SUPPORTED
+#    define PNG_sCAL_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_pHYs
+#  define PNG_WRITE_pHYs_SUPPORTED
+#  ifndef PNG_pHYs_SUPPORTED
+#    define PNG_pHYs_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_sBIT
+#  define PNG_WRITE_sBIT_SUPPORTED
+#  ifndef PNG_sBIT_SUPPORTED
+#    define PNG_sBIT_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_sPLT
+#  define PNG_WRITE_sPLT_SUPPORTED
+#  ifndef PNG_sPLT_SUPPORTED
+#    define PNG_sPLT_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_sRGB
+#  define PNG_WRITE_sRGB_SUPPORTED
+#  ifndef PNG_sRGB_SUPPORTED
+#    define PNG_sRGB_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_tEXt
+#  define PNG_WRITE_tEXt_SUPPORTED
+#  ifndef PNG_tEXt_SUPPORTED
+#    define PNG_tEXt_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_tIME
+#  define PNG_WRITE_tIME_SUPPORTED
+#  ifndef PNG_tIME_SUPPORTED
+#    define PNG_tIME_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_tRNS
+#  define PNG_WRITE_tRNS_SUPPORTED
+#  ifndef PNG_tRNS_SUPPORTED
+#    define PNG_tRNS_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_zTXt
+#  define PNG_WRITE_zTXt_SUPPORTED
+#  ifndef PNG_zTXt_SUPPORTED
+#    define PNG_zTXt_SUPPORTED
+#  endif
+#endif
+#ifndef PNG_NO_WRITE_UNKNOWN_CHUNKS
+#  define PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
+#  ifndef PNG_UNKNOWN_CHUNKS_SUPPORTED
+#    define PNG_UNKNOWN_CHUNKS_SUPPORTED
+#  endif
+#  ifndef PNG_NO_HANDLE_AS_UNKNOWN
+#     ifndef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+#       define PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+#     endif
+#  endif
+#endif
+#if defined(PNG_WRITE_iTXt_SUPPORTED) || defined(PNG_WRITE_tEXt_SUPPORTED) || \
+    defined(PNG_WRITE_zTXt_SUPPORTED)
+#  define PNG_WRITE_TEXT_SUPPORTED
+#  ifndef PNG_TEXT_SUPPORTED
+#    define PNG_TEXT_SUPPORTED
+#  endif
+#endif
+
+#endif /* PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED */
+
+/* Turn this off to disable png_read_png() and
+ * png_write_png() and leave the row_pointers member
+ * out of the info structure.
+ */
+#ifndef PNG_NO_INFO_IMAGE
+#  define PNG_INFO_IMAGE_SUPPORTED
+#endif
+
+/* need the time information for reading tIME chunks */
+#if defined(PNG_tIME_SUPPORTED)
+#  if !defined(_WIN32_WCE)
+     /* "time.h" functions are not supported on WindowsCE */
+#    include <time.h>
+#  endif
+#endif
+
+/* Some typedefs to get us started.  These should be safe on most of the
+ * common platforms.  The typedefs should be at least as large as the
+ * numbers suggest (a png_uint_32 must be at least 32 bits long), but they
+ * don't have to be exactly that size.  Some compilers dislike passing
+ * unsigned shorts as function parameters, so you may be better off using
+ * unsigned int for png_uint_16.  Likewise, for 64-bit systems, you may
+ * want to have unsigned int for png_uint_32 instead of unsigned long.
+ */
+
+typedef unsigned long png_uint_32;
+typedef long png_int_32;
+typedef unsigned short png_uint_16;
+typedef short png_int_16;
+typedef unsigned char png_byte;
+
+/* This is usually size_t.  It is typedef'ed just in case you need it to
+   change (I'm not sure if you will or not, so I thought I'd be safe) */
+#ifdef PNG_SIZE_T
+   typedef PNG_SIZE_T png_size_t;
+#  define png_sizeof(x) png_convert_size(sizeof (x))
+#else
+   typedef size_t png_size_t;
+#  define png_sizeof(x) sizeof (x)
+#endif
+
+/* The following is needed for medium model support.  It cannot be in the
+ * PNG_INTERNAL section.  Needs modification for other compilers besides
+ * MSC.  Model independent support declares all arrays and pointers to be
+ * large using the far keyword.  The zlib version used must also support
+ * model independent data.  As of version zlib 1.0.4, the necessary changes
+ * have been made in zlib.  The USE_FAR_KEYWORD define triggers other
+ * changes that are needed. (Tim Wegner)
+ */
+
+/* Separate compiler dependencies (problem here is that zlib.h always
+   defines FAR. (SJT) */
+#ifdef __BORLANDC__
+#  if defined(__LARGE__) || defined(__HUGE__) || defined(__COMPACT__)
+#    define LDATA 1
+#  else
+#    define LDATA 0
+#  endif
+   /* GRR:  why is Cygwin in here?  Cygwin is not Borland C... */
+#  if !defined(__WIN32__) && !defined(__FLAT__) && !defined(__CYGWIN__)
+#    define PNG_MAX_MALLOC_64K
+#    if (LDATA != 1)
+#      ifndef FAR
+#        define FAR __far
+#      endif
+#      define USE_FAR_KEYWORD
+#    endif   /* LDATA != 1 */
+     /* Possibly useful for moving data out of default segment.
+      * Uncomment it if you want. Could also define FARDATA as
+      * const if your compiler supports it. (SJT)
+#    define FARDATA FAR
+      */
+#  endif  /* __WIN32__, __FLAT__, __CYGWIN__ */
+#endif   /* __BORLANDC__ */
+
+
+/* Suggest testing for specific compiler first before testing for
+ * FAR.  The Watcom compiler defines both __MEDIUM__ and M_I86MM,
+ * making reliance oncertain keywords suspect. (SJT)
+ */
+
+/* MSC Medium model */
+#if defined(FAR)
+#  if defined(M_I86MM)
+#    define USE_FAR_KEYWORD
+#    define FARDATA FAR
+#    include <dos.h>
+#  endif
+#endif
+
+/* SJT: default case */
+#ifndef FAR
+#  define FAR
+#endif
+
+/* At this point FAR is always defined */
+#ifndef FARDATA
+#  define FARDATA
+#endif
+
+/* Typedef for floating-point numbers that are converted
+   to fixed-point with a multiple of 100,000, e.g., int_gamma */
+typedef png_int_32 png_fixed_point;
+
+/* Add typedefs for pointers */
+typedef void            FAR * png_voidp;
+typedef png_byte        FAR * png_bytep;
+typedef png_uint_32     FAR * png_uint_32p;
+typedef png_int_32      FAR * png_int_32p;
+typedef png_uint_16     FAR * png_uint_16p;
+typedef png_int_16      FAR * png_int_16p;
+typedef PNG_CONST char  FAR * png_const_charp;
+typedef char            FAR * png_charp;
+typedef png_fixed_point FAR * png_fixed_point_p;
+
+#ifndef PNG_NO_STDIO
+#if defined(_WIN32_WCE)
+typedef HANDLE                png_FILE_p;
+#else
+typedef FILE                * png_FILE_p;
+#endif
+#endif
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+typedef double          FAR * png_doublep;
+#endif
+
+/* Pointers to pointers; i.e. arrays */
+typedef png_byte        FAR * FAR * png_bytepp;
+typedef png_uint_32     FAR * FAR * png_uint_32pp;
+typedef png_int_32      FAR * FAR * png_int_32pp;
+typedef png_uint_16     FAR * FAR * png_uint_16pp;
+typedef png_int_16      FAR * FAR * png_int_16pp;
+typedef PNG_CONST char  FAR * FAR * png_const_charpp;
+typedef char            FAR * FAR * png_charpp;
+typedef png_fixed_point FAR * FAR * png_fixed_point_pp;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+typedef double          FAR * FAR * png_doublepp;
+#endif
+
+/* Pointers to pointers to pointers; i.e., pointer to array */
+typedef char            FAR * FAR * FAR * png_charppp;
+
+#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
+/* SPC -  Is this stuff deprecated? */
+/* It'll be removed as of libpng-1.3.0 - GR-P */
+/* libpng typedefs for types in zlib. If zlib changes
+ * or another compression library is used, then change these.
+ * Eliminates need to change all the source files.
+ */
+typedef charf *         png_zcharp;
+typedef charf * FAR *   png_zcharpp;
+typedef z_stream FAR *  png_zstreamp;
+#endif /* (PNG_1_0_X) || defined(PNG_1_2_X) */
+
+/*
+ * Define PNG_BUILD_DLL if the module being built is a Windows
+ * LIBPNG DLL.
+ *
+ * Define PNG_USE_DLL if you want to *link* to the Windows LIBPNG DLL.
+ * It is equivalent to Microsoft predefined macro _DLL that is
+ * automatically defined when you compile using the share
+ * version of the CRT (C Run-Time library)
+ *
+ * The cygwin mods make this behavior a little different:
+ * Define PNG_BUILD_DLL if you are building a dll for use with cygwin
+ * Define PNG_STATIC if you are building a static library for use with cygwin,
+ *   -or- if you are building an application that you want to link to the
+ *   static library.
+ * PNG_USE_DLL is defined by default (no user action needed) unless one of
+ *   the other flags is defined.
+ */
+
+#if !defined(PNG_DLL) && (defined(PNG_BUILD_DLL) || defined(PNG_USE_DLL))
+#  define PNG_DLL
+#endif
+/* If CYGWIN, then disallow GLOBAL ARRAYS unless building a static lib.
+ * When building a static lib, default to no GLOBAL ARRAYS, but allow
+ * command-line override
+ */
+#if defined(__CYGWIN__)
+#  if !defined(PNG_STATIC)
+#    if defined(PNG_USE_GLOBAL_ARRAYS)
+#      undef PNG_USE_GLOBAL_ARRAYS
+#    endif
+#    if !defined(PNG_USE_LOCAL_ARRAYS)
+#      define PNG_USE_LOCAL_ARRAYS
+#    endif
+#  else
+#    if defined(PNG_USE_LOCAL_ARRAYS) || defined(PNG_NO_GLOBAL_ARRAYS)
+#      if defined(PNG_USE_GLOBAL_ARRAYS)
+#        undef PNG_USE_GLOBAL_ARRAYS
+#      endif
+#    endif
+#  endif
+#  if !defined(PNG_USE_LOCAL_ARRAYS) && !defined(PNG_USE_GLOBAL_ARRAYS)
+#    define PNG_USE_LOCAL_ARRAYS
+#  endif
+#endif
+
+/* Do not use global arrays (helps with building DLL's)
+ * They are no longer used in libpng itself, since version 1.0.5c,
+ * but might be required for some pre-1.0.5c applications.
+ */
+#if !defined(PNG_USE_LOCAL_ARRAYS) && !defined(PNG_USE_GLOBAL_ARRAYS)
+#  if defined(PNG_NO_GLOBAL_ARRAYS) || (defined(__GNUC__) && defined(PNG_DLL))
+#    define PNG_USE_LOCAL_ARRAYS
+#  else
+#    define PNG_USE_GLOBAL_ARRAYS
+#  endif
+#endif
+
+#if defined(__CYGWIN__)
+#  undef PNGAPI
+#  define PNGAPI __cdecl
+#  undef PNG_IMPEXP
+#  define PNG_IMPEXP
+#endif  
+
+/* If you define PNGAPI, e.g., with compiler option "-DPNGAPI=__stdcall",
+ * you may get warnings regarding the linkage of png_zalloc and png_zfree.
+ * Don't ignore those warnings; you must also reset the default calling
+ * convention in your compiler to match your PNGAPI, and you must build
+ * zlib and your applications the same way you build libpng.
+ */
+
+#if defined(__MINGW32__) && !defined(PNG_MODULEDEF)
+#  ifndef PNG_NO_MODULEDEF
+#    define PNG_NO_MODULEDEF
+#  endif
+#endif
+
+#if !defined(PNG_IMPEXP) && defined(PNG_BUILD_DLL) && !defined(PNG_NO_MODULEDEF)
+#  define PNG_IMPEXP
+#endif
+
+#if defined(PNG_DLL) || defined(_DLL) || defined(__DLL__ ) || \
+    (( defined(_Windows) || defined(_WINDOWS) || \
+       defined(WIN32) || defined(_WIN32) || defined(__WIN32__) ))
+
+#  ifndef PNGAPI
+#     if defined(__GNUC__) || (defined (_MSC_VER) && (_MSC_VER >= 800))
+#        define PNGAPI __cdecl
+#     else
+#        define PNGAPI _cdecl
+#     endif
+#  endif
+
+#  if !defined(PNG_IMPEXP) && (!defined(PNG_DLL) || \
+       0 /* WINCOMPILER_WITH_NO_SUPPORT_FOR_DECLIMPEXP */)
+#     define PNG_IMPEXP
+#  endif
+
+#  if !defined(PNG_IMPEXP)
+
+#     define PNG_EXPORT_TYPE1(type,symbol)  PNG_IMPEXP type PNGAPI symbol
+#     define PNG_EXPORT_TYPE2(type,symbol)  type PNG_IMPEXP PNGAPI symbol
+
+      /* Borland/Microsoft */
+#     if defined(_MSC_VER) || defined(__BORLANDC__)
+#        if (_MSC_VER >= 800) || (__BORLANDC__ >= 0x500)
+#           define PNG_EXPORT PNG_EXPORT_TYPE1
+#        else
+#           define PNG_EXPORT PNG_EXPORT_TYPE2
+#           if defined(PNG_BUILD_DLL)
+#              define PNG_IMPEXP __export
+#           else
+#              define PNG_IMPEXP /*__import */ /* doesn't exist AFAIK in
+                                                 VC++ */
+#           endif                             /* Exists in Borland C++ for
+                                                 C++ classes (== huge) */
+#        endif
+#     endif
+
+#     if !defined(PNG_IMPEXP)
+#        if defined(PNG_BUILD_DLL)
+#           define PNG_IMPEXP __declspec(dllexport)
+#        else
+#           define PNG_IMPEXP __declspec(dllimport)
+#        endif
+#     endif
+#  endif  /* PNG_IMPEXP */
+#else /* !(DLL || non-cygwin WINDOWS) */
+#   if (defined(__IBMC__) || defined(__IBMCPP__)) && defined(__OS2__)
+#      ifndef PNGAPI
+#         define PNGAPI _System
+#      endif
+#   else
+#      if 0 /* ... other platforms, with other meanings */
+#      endif
+#   endif
+#endif
+
+#ifndef PNGAPI
+#  define PNGAPI
+#endif
+#ifndef PNG_IMPEXP
+#  define PNG_IMPEXP
+#endif
+
+#ifdef PNG_BUILDSYMS
+#  ifndef PNG_EXPORT
+#    define PNG_EXPORT(type,symbol) PNG_FUNCTION_EXPORT symbol END
+#  endif
+#  ifdef PNG_USE_GLOBAL_ARRAYS
+#    ifndef PNG_EXPORT_VAR
+#      define PNG_EXPORT_VAR(type) PNG_DATA_EXPORT
+#    endif
+#  endif
+#endif
+
+#ifndef PNG_EXPORT
+#  define PNG_EXPORT(type,symbol) PNG_IMPEXP type PNGAPI symbol
+#endif
+
+#ifdef PNG_USE_GLOBAL_ARRAYS
+#  ifndef PNG_EXPORT_VAR
+#    define PNG_EXPORT_VAR(type) extern PNG_IMPEXP type
+#  endif
+#endif
+
+/* User may want to use these so they are not in PNG_INTERNAL. Any library
+ * functions that are passed far data must be model independent.
+ */
+
+#ifndef PNG_ABORT
+#  define PNG_ABORT() abort()
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+#  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
+#else
+#  define png_jmpbuf(png_ptr) \
+   (LIBPNG_WAS_COMPILED_WITH__PNG_SETJMP_NOT_SUPPORTED)
+#endif
+
+#if defined(USE_FAR_KEYWORD)  /* memory model independent fns */
+/* use this to make far-to-near assignments */
+#  define CHECK   1
+#  define NOCHECK 0
+#  define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
+#  define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
+#  define png_strcpy  _fstrcpy
+#  define png_strncpy _fstrncpy   /* Added to v 1.2.6 */
+#  define png_strlen  _fstrlen
+#  define png_memcmp  _fmemcmp    /* SJT: added */
+#  define png_memcpy  _fmemcpy
+#  define png_memset  _fmemset
+#else /* use the usual functions */
+#  define CVT_PTR(ptr)         (ptr)
+#  define CVT_PTR_NOCHECK(ptr) (ptr)
+#  define png_strcpy  strcpy
+#  define png_strncpy strncpy     /* Added to v 1.2.6 */
+#  define png_strlen  strlen
+#  define png_memcmp  memcmp      /* SJT: added */
+#  define png_memcpy  memcpy
+#  define png_memset  memset
+#endif
+/* End of memory model independent support */
+
+/* Just a little check that someone hasn't tried to define something
+ * contradictory.
+ */
+#if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
+#  undef PNG_ZBUF_SIZE
+#  define PNG_ZBUF_SIZE 65536L
+#endif
+
+#ifdef PNG_READ_SUPPORTED
+/* Prior to libpng-1.0.9, this block was in pngasmrd.h */
+#if defined(PNG_INTERNAL)
+
+/* These are the default thresholds before the MMX code kicks in; if either
+ * rowbytes or bitdepth is below the threshold, plain C code is used.  These
+ * can be overridden at runtime via the png_set_mmx_thresholds() call in
+ * libpng 1.2.0 and later.  The values below were chosen by Intel.
+ */
+
+#ifndef PNG_MMX_ROWBYTES_THRESHOLD_DEFAULT
+#  define PNG_MMX_ROWBYTES_THRESHOLD_DEFAULT  128  /*  >=  */
+#endif
+#ifndef PNG_MMX_BITDEPTH_THRESHOLD_DEFAULT
+#  define PNG_MMX_BITDEPTH_THRESHOLD_DEFAULT  9    /*  >=  */   
+#endif
+
+/* Set this in the makefile for VC++ on Pentium, not here. */
+/* Platform must be Pentium.  Makefile must assemble and load pngvcrd.c .
+ * MMX will be detected at run time and used if present.
+ */
+#ifdef PNG_USE_PNGVCRD
+#  define PNG_HAVE_ASSEMBLER_COMBINE_ROW
+#  define PNG_HAVE_ASSEMBLER_READ_INTERLACE
+#  define PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+#endif
+
+/* Set this in the makefile for gcc/as on Pentium, not here. */
+/* Platform must be Pentium.  Makefile must assemble and load pnggccrd.c .
+ * MMX will be detected at run time and used if present.
+ */
+#ifdef PNG_USE_PNGGCCRD
+#  define PNG_HAVE_ASSEMBLER_COMBINE_ROW
+#  define PNG_HAVE_ASSEMBLER_READ_INTERLACE
+#  define PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+#endif
+/* - see pnggccrd.c for info about what is currently enabled */
+
+#endif /* PNG_INTERNAL */
+#endif /* PNG_READ_SUPPORTED */
+
+/* Added at libpng-1.2.8 */
+#endif /* PNG_VERSION_INFO_ONLY */
+
+#endif /* PNGCONF_H */
diff --git a/gs/libpng/pngerror.c b/gs/libpng/pngerror.c
new file mode 100644
index 000000000..6fa401237
--- /dev/null
+++ b/gs/libpng/pngerror.c
@@ -0,0 +1,295 @@
+
+/* pngerror.c - stub functions for i/o and memory allocation
+ *
+ * libpng version 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file provides a location for all error handling.  Users who
+ * need special error handling are expected to write replacement functions
+ * and use png_set_error_fn() to use those functions.  See the instructions
+ * at each function.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+static void /* PRIVATE */
+png_default_error PNGARG((png_structp png_ptr,
+  png_const_charp error_message));
+static void /* PRIVATE */
+png_default_warning PNGARG((png_structp png_ptr,
+  png_const_charp warning_message));
+
+/* This function is called whenever there is a fatal error.  This function
+ * should not be changed.  If there is a need to handle errors differently,
+ * you should supply a replacement error function and use png_set_error_fn()
+ * to replace the error function at run-time.
+ */
+void PNGAPI
+png_error(png_structp png_ptr, png_const_charp error_message)
+{
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+   char msg[16];
+   if (png_ptr->flags&(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
+   {
+     if (*error_message == '#')
+     {
+         int offset;
+         for (offset=1; offset<15; offset++)
+            if (*(error_message+offset) == ' ')
+                break;
+         if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
+         {
+            int i;
+            for (i=0; i<offset-1; i++)
+               msg[i]=error_message[i+1];
+            msg[i]='\0';
+            error_message=msg;
+         }
+         else
+            error_message+=offset;
+     }
+     else
+     {
+         if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
+         {
+            msg[0]='0';        
+            msg[1]='\0';
+            error_message=msg;
+         }
+     }
+   }
+#endif
+   if (png_ptr != NULL && png_ptr->error_fn != NULL)
+      (*(png_ptr->error_fn))(png_ptr, error_message);
+
+   /* If the custom handler doesn't exist, or if it returns,
+      use the default handler, which will not return. */
+   png_default_error(png_ptr, error_message);
+}
+
+/* This function is called whenever there is a non-fatal error.  This function
+ * should not be changed.  If there is a need to handle warnings differently,
+ * you should supply a replacement warning function and use
+ * png_set_error_fn() to replace the warning function at run-time.
+ */
+void PNGAPI
+png_warning(png_structp png_ptr, png_const_charp warning_message)
+{
+   int offset = 0;
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+   if (png_ptr->flags&(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
+#endif
+   {
+     if (*warning_message == '#')
+     {
+         for (offset=1; offset<15; offset++)
+            if (*(warning_message+offset) == ' ')
+                break;
+     }
+   }
+   if (png_ptr != NULL && png_ptr->warning_fn != NULL)
+      (*(png_ptr->warning_fn))(png_ptr, warning_message+offset);
+   else
+      png_default_warning(png_ptr, warning_message+offset);
+}
+
+/* These utilities are used internally to build an error message that relates
+ * to the current chunk.  The chunk name comes from png_ptr->chunk_name,
+ * this is used to prefix the message.  The message is limited in length
+ * to 63 bytes, the name characters are output as hex digits wrapped in []
+ * if the character is invalid.
+ */
+#define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97))
+static PNG_CONST char png_digit[16] = {
+   '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
+   'A', 'B', 'C', 'D', 'E', 'F'
+};
+
+static void /* PRIVATE */
+png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp
+   error_message)
+{
+   int iout = 0, iin = 0;
+
+   while (iin < 4)
+   {
+      int c = png_ptr->chunk_name[iin++];
+      if (isnonalpha(c))
+      {
+         buffer[iout++] = '[';
+         buffer[iout++] = png_digit[(c & 0xf0) >> 4];
+         buffer[iout++] = png_digit[c & 0x0f];
+         buffer[iout++] = ']';
+      }
+      else
+      {
+         buffer[iout++] = (png_byte)c;
+      }
+   }
+
+   if (error_message == NULL)
+      buffer[iout] = 0;
+   else
+   {
+      buffer[iout++] = ':';
+      buffer[iout++] = ' ';
+      png_strncpy(buffer+iout, error_message, 63);
+      buffer[iout+63] = 0;
+   }
+}
+
+void PNGAPI
+png_chunk_error(png_structp png_ptr, png_const_charp error_message)
+{
+   char msg[18+64];
+   png_format_buffer(png_ptr, msg, error_message);
+   png_error(png_ptr, msg);
+}
+
+void PNGAPI
+png_chunk_warning(png_structp png_ptr, png_const_charp warning_message)
+{
+   char msg[18+64];
+   png_format_buffer(png_ptr, msg, warning_message);
+   png_warning(png_ptr, msg);
+}
+
+/* This is the default error handling function.  Note that replacements for
+ * this function MUST NOT RETURN, or the program will likely crash.  This
+ * function is used by default, or if the program supplies NULL for the
+ * error function pointer in png_set_error_fn().
+ */
+static void /* PRIVATE */
+png_default_error(png_structp png_ptr, png_const_charp error_message)
+{
+#ifndef PNG_NO_CONSOLE_IO
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+   if (*error_message == '#')
+   {
+     int offset;
+     char error_number[16];
+     for (offset=0; offset<15; offset++)
+     {
+         error_number[offset] = *(error_message+offset+1);
+         if (*(error_message+offset) == ' ')
+             break;
+     }
+     if((offset > 1) && (offset < 15))
+     {
+       error_number[offset-1]='\0';
+       fprintf(stderr, "libpng error no. %s: %s\n", error_number,
+          error_message+offset);
+     }
+     else
+       fprintf(stderr, "libpng error: %s, offset=%d\n", error_message,offset);
+   }
+   else
+#endif
+   fprintf(stderr, "libpng error: %s\n", error_message);
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+#  ifdef USE_FAR_KEYWORD
+   {
+      jmp_buf jmpbuf;
+      png_memcpy(jmpbuf,png_ptr->jmpbuf,png_sizeof(jmp_buf));
+      longjmp(jmpbuf, 1);
+   }
+#  else
+   longjmp(png_ptr->jmpbuf, 1);
+# endif
+#else
+   /* make compiler happy */ ;
+   if (png_ptr)
+   PNG_ABORT();
+#endif
+#ifdef PNG_NO_CONSOLE_IO
+   /* make compiler happy */ ;
+   if (&error_message != NULL)
+      return;
+#endif
+}
+
+/* This function is called when there is a warning, but the library thinks
+ * it can continue anyway.  Replacement functions don't have to do anything
+ * here if you don't want them to.  In the default configuration, png_ptr is
+ * not used, but it is passed in case it may be useful.
+ */
+static void /* PRIVATE */
+png_default_warning(png_structp png_ptr, png_const_charp warning_message)
+{
+#ifndef PNG_NO_CONSOLE_IO
+#  ifdef PNG_ERROR_NUMBERS_SUPPORTED
+   if (*warning_message == '#')
+   {
+     int offset;
+     char warning_number[16];
+     for (offset=0; offset<15; offset++)
+     {
+        warning_number[offset]=*(warning_message+offset+1);
+        if (*(warning_message+offset) == ' ')
+            break;
+     }
+     if((offset > 1) && (offset < 15))
+     {
+       warning_number[offset-1]='\0';
+       fprintf(stderr, "libpng warning no. %s: %s\n", warning_number,
+          warning_message+offset);
+     }
+     else
+       fprintf(stderr, "libpng warning: %s\n", warning_message);
+   }
+   else
+#  endif
+     fprintf(stderr, "libpng warning: %s\n", warning_message);
+#else
+   /* make compiler happy */ ;
+   if (warning_message)
+     return;
+#endif
+   /* make compiler happy */ ;
+   if (png_ptr)
+      return;
+}
+
+/* This function is called when the application wants to use another method
+ * of handling errors and warnings.  Note that the error function MUST NOT
+ * return to the calling routine or serious problems will occur.  The return
+ * method used in the default routine calls longjmp(png_ptr->jmpbuf, 1)
+ */
+void PNGAPI
+png_set_error_fn(png_structp png_ptr, png_voidp error_ptr,
+   png_error_ptr error_fn, png_error_ptr warning_fn)
+{
+   png_ptr->error_ptr = error_ptr;
+   png_ptr->error_fn = error_fn;
+   png_ptr->warning_fn = warning_fn;
+}
+
+
+/* This function returns a pointer to the error_ptr associated with the user
+ * functions.  The application should free any memory associated with this
+ * pointer before png_write_destroy and png_read_destroy are called.
+ */
+png_voidp PNGAPI
+png_get_error_ptr(png_structp png_ptr)
+{
+   return ((png_voidp)png_ptr->error_ptr);
+}
+
+
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+void PNGAPI
+png_set_strip_error_numbers(png_structp png_ptr, png_uint_32 strip_mode)
+{
+   if(png_ptr != NULL)
+   {
+     png_ptr->flags &=
+       ((~(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))&strip_mode);
+   }
+}
+#endif
diff --git a/gs/libpng/pnggccrd.c b/gs/libpng/pnggccrd.c
new file mode 100644
index 000000000..248e1b3bb
--- /dev/null
+++ b/gs/libpng/pnggccrd.c
@@ -0,0 +1,5408 @@
+/* pnggccrd.c - mixed C/assembler version of utilities to read a PNG file
+ *
+ * For Intel x86 CPU (Pentium-MMX or later) and GNU C compiler.
+ *
+ *     See http://www.intel.com/drg/pentiumII/appnotes/916/916.htm
+ *     and http://www.intel.com/drg/pentiumII/appnotes/923/923.htm
+ *     for Intel's performance analysis of the MMX vs. non-MMX code.
+ *
+ * libpng version 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * Copyright (c) 1998, Intel Corporation
+ *
+ * Based on MSVC code contributed by Nirav Chhatrapati, Intel Corp., 1998.
+ * Interface to libpng contributed by Gilles Vollant, 1999.
+ * GNU C port by Greg Roelofs, 1999-2001.
+ *
+ * Lines 2350-4300 converted in place with intel2gas 1.3.1:
+ *
+ *   intel2gas -mdI pnggccrd.c.partially-msvc -o pnggccrd.c
+ *
+ * and then cleaned up by hand.  See http://hermes.terminal.at/intel2gas/ .
+ *
+ * NOTE:  A sufficiently recent version of GNU as (or as.exe under DOS/Windows)
+ *        is required to assemble the newer MMX instructions such as movq.
+ *        For djgpp, see
+ *
+ *           ftp://ftp.simtel.net/pub/simtelnet/gnu/djgpp/v2gnu/bnu281b.zip
+ *
+ *        (or a later version in the same directory).  For Linux, check your
+ *        distribution's web site(s) or try these links:
+ *
+ *           http://rufus.w3.org/linux/RPM/binutils.html
+ *           http://www.debian.org/Packages/stable/devel/binutils.html
+ *           ftp://ftp.slackware.com/pub/linux/slackware/slackware/slakware/d1/
+ *             binutils.tgz
+ *
+ *        For other platforms, see the main GNU site:
+ *
+ *           ftp://ftp.gnu.org/pub/gnu/binutils/
+ *
+ *        Version 2.5.2l.15 is definitely too old...
+ */
+
+/*
+ * TEMPORARY PORTING NOTES AND CHANGELOG (mostly by Greg Roelofs)
+ * =====================================
+ *
+ * 19991006:
+ *  - fixed sign error in post-MMX cleanup code (16- & 32-bit cases)
+ *
+ * 19991007:
+ *  - additional optimizations (possible or definite):
+ *     x [DONE] write MMX code for 64-bit case (pixel_bytes == 8) [not tested]
+ *     - write MMX code for 48-bit case (pixel_bytes == 6)
+ *     - figure out what's up with 24-bit case (pixel_bytes == 3):
+ *        why subtract 8 from width_mmx in the pass 4/5 case?
+ *        (only width_mmx case) (near line 1606)
+ *     x [DONE] replace pixel_bytes within each block with the true
+ *        constant value (or are compilers smart enough to do that?)
+ *     - rewrite all MMX interlacing code so it's aligned with
+ *        the *beginning* of the row buffer, not the end.  This
+ *        would not only allow one to eliminate half of the memory
+ *        writes for odd passes (that is, pass == odd), it may also
+ *        eliminate some unaligned-data-access exceptions (assuming
+ *        there's a penalty for not aligning 64-bit accesses on
+ *        64-bit boundaries).  The only catch is that the "leftover"
+ *        pixel(s) at the end of the row would have to be saved,
+ *        but there are enough unused MMX registers in every case,
+ *        so this is not a problem.  A further benefit is that the
+ *        post-MMX cleanup code (C code) in at least some of the
+ *        cases could be done within the assembler block.
+ *  x [DONE] the "v3 v2 v1 v0 v7 v6 v5 v4" comments are confusing,
+ *     inconsistent, and don't match the MMX Programmer's Reference
+ *     Manual conventions anyway.  They should be changed to
+ *     "b7 b6 b5 b4 b3 b2 b1 b0," where b0 indicates the byte that
+ *     was lowest in memory (e.g., corresponding to a left pixel)
+ *     and b7 is the byte that was highest (e.g., a right pixel).
+ *
+ * 19991016:
+ *  - Brennan's Guide notwithstanding, gcc under Linux does *not*
+ *     want globals prefixed by underscores when referencing them--
+ *     i.e., if the variable is const4, then refer to it as const4,
+ *     not _const4.  This seems to be a djgpp-specific requirement.
+ *     Also, such variables apparently *must* be declared outside
+ *     of functions; neither static nor automatic variables work if
+ *     defined within the scope of a single function, but both
+ *     static and truly global (multi-module) variables work fine.
+ *
+ * 19991023:
+ *  - fixed png_combine_row() non-MMX replication bug (odd passes only?)
+ *  - switched from string-concatenation-with-macros to cleaner method of
+ *     renaming global variables for djgpp--i.e., always use prefixes in
+ *     inlined assembler code (== strings) and conditionally rename the
+ *     variables, not the other way around.  Hence _const4, _mask8_0, etc.
+ *
+ * 19991024:
+ *  - fixed mmxsupport()/png_do_read_interlace() first-row bug
+ *     This one was severely weird:  even though mmxsupport() doesn't touch
+ *     ebx (where "row" pointer was stored), it nevertheless managed to zero
+ *     the register (even in static/non-fPIC code--see below), which in turn
+ *     caused png_do_read_interlace() to return prematurely on the first row of
+ *     interlaced images (i.e., without expanding the interlaced pixels).
+ *     Inspection of the generated assembly code didn't turn up any clues,
+ *     although it did point at a minor optimization (i.e., get rid of
+ *     mmx_supported_local variable and just use eax).  Possibly the CPUID
+ *     instruction is more destructive than it looks?  (Not yet checked.)
+ *  - "info gcc" was next to useless, so compared fPIC and non-fPIC assembly
+ *     listings...  Apparently register spillage has to do with ebx, since
+ *     it's used to index the global offset table.  Commenting it out of the
+ *     input-reg lists in png_combine_row() eliminated compiler barfage, so
+ *     ifdef'd with __PIC__ macro:  if defined, use a global for unmask
+ *
+ * 19991107:
+ *  - verified CPUID clobberage:  12-char string constant ("GenuineIntel",
+ *     "AuthenticAMD", etc.) placed in ebx:ecx:edx.  Still need to polish.
+ *
+ * 19991120:
+ *  - made "diff" variable (now "_dif") global to simplify conversion of
+ *     filtering routines (running out of regs, sigh).  "diff" is still used
+ *     in interlacing routines, however.
+ *  - fixed up both versions of mmxsupport() (ORIG_THAT_USED_TO_CLOBBER_EBX
+ *     macro determines which is used); original not yet tested.
+ *
+ * 20000213:
+ *  - when compiling with gcc, be sure to use  -fomit-frame-pointer
+ *
+ * 20000319:
+ *  - fixed a register-name typo in png_do_read_interlace(), default (MMX) case,
+ *     pass == 4 or 5, that caused visible corruption of interlaced images
+ *
+ * 20000623:
+ *  - Various problems were reported with gcc 2.95.2 in the Cygwin environment,
+ *     many of the form "forbidden register 0 (ax) was spilled for class AREG."
+ *     This is explained at http://gcc.gnu.org/fom_serv/cache/23.html, and
+ *     Chuck Wilson supplied a patch involving dummy output registers.  See
+ *     http://sourceforge.net/bugs/?func=detailbug&bug_id=108741&group_id=5624
+ *     for the original (anonymous) SourceForge bug report.
+ *
+ * 20000706:
+ *  - Chuck Wilson passed along these remaining gcc 2.95.2 errors:
+ *       pnggccrd.c: In function `png_combine_row':
+ *       pnggccrd.c:525: more than 10 operands in `asm'
+ *       pnggccrd.c:669: more than 10 operands in `asm'
+ *       pnggccrd.c:828: more than 10 operands in `asm'
+ *       pnggccrd.c:994: more than 10 operands in `asm'
+ *       pnggccrd.c:1177: more than 10 operands in `asm'
+ *     They are all the same problem and can be worked around by using the
+ *     global _unmask variable unconditionally, not just in the -fPIC case.
+ *     Reportedly earlier versions of gcc also have the problem with more than
+ *     10 operands; they just don't report it.  Much strangeness ensues, etc.
+ *
+ * 20000729:
+ *  - enabled png_read_filter_row_mmx_up() (shortest remaining unconverted
+ *     MMX routine); began converting png_read_filter_row_mmx_sub()
+ *  - to finish remaining sections:
+ *     - clean up indentation and comments
+ *     - preload local variables
+ *     - add output and input regs (order of former determines numerical
+ *        mapping of latter)
+ *     - avoid all usage of ebx (including bx, bh, bl) register [20000823]
+ *     - remove "$" from addressing of Shift and Mask variables [20000823]
+ *
+ * 20000731:
+ *  - global union vars causing segfaults in png_read_filter_row_mmx_sub()?
+ *
+ * 20000822:
+ *  - ARGH, stupid png_read_filter_row_mmx_sub() segfault only happens with
+ *     shared-library (-fPIC) version!  Code works just fine as part of static
+ *     library.  Damn damn damn damn damn, should have tested that sooner.
+ *     ebx is getting clobbered again (explicitly this time); need to save it
+ *     on stack or rewrite asm code to avoid using it altogether.  Blargh!
+ *
+ * 20000823:
+ *  - first section was trickiest; all remaining sections have ebx -> edx now.
+ *     (-fPIC works again.)  Also added missing underscores to various Shift*
+ *     and *Mask* globals and got rid of leading "$" signs.
+ *
+ * 20000826:
+ *  - added visual separators to help navigate microscopic printed copies
+ *     (http://pobox.com/~newt/code/gpr-latest.zip, mode 10); started working
+ *     on png_read_filter_row_mmx_avg()
+ *
+ * 20000828:
+ *  - finished png_read_filter_row_mmx_avg():  only Paeth left! (930 lines...)
+ *     What the hell, did png_read_filter_row_mmx_paeth(), too.  Comments not
+ *     cleaned up/shortened in either routine, but functionality is complete
+ *     and seems to be working fine.
+ *
+ * 20000829:
+ *  - ahhh, figured out last(?) bit of gcc/gas asm-fu:  if register is listed
+ *     as an input reg (with dummy output variables, etc.), then it *cannot*
+ *     also appear in the clobber list or gcc 2.95.2 will barf.  The solution
+ *     is simple enough...
+ *
+ * 20000914:
+ *  - bug in png_read_filter_row_mmx_avg():  16-bit grayscale not handled
+ *     correctly (but 48-bit RGB just fine)
+ *
+ * 20000916:
+ *  - fixed bug in png_read_filter_row_mmx_avg(), bpp == 2 case; three errors:
+ *     - "_ShiftBpp.use = 24;"      should have been   "_ShiftBpp.use = 16;"
+ *     - "_ShiftRem.use = 40;"      should have been   "_ShiftRem.use = 48;"
+ *     - "psllq _ShiftRem, %%mm2"   should have been   "psrlq _ShiftRem, %%mm2"
+ *
+ * 20010101:
+ *  - added new png_init_mmx_flags() function (here only because it needs to
+ *     call mmxsupport(), which should probably become global png_mmxsupport());
+ *     modified other MMX routines to run conditionally (png_ptr->asm_flags)
+ *
+ * 20010103:
+ *  - renamed mmxsupport() to png_mmx_support(), with auto-set of mmx_supported,
+ *     and made it public; moved png_init_mmx_flags() to png.c as internal func
+ *
+ * 20010104:
+ *  - removed dependency on png_read_filter_row_c() (C code already duplicated
+ *     within MMX version of png_read_filter_row()) so no longer necessary to
+ *     compile it into pngrutil.o
+ *
+ * 20010310:
+ *  - fixed buffer-overrun bug in png_combine_row() C code (non-MMX)
+ *
+ * 20020304:
+ *  - eliminated incorrect use of width_mmx in pixel_bytes == 8 case
+ *
+ * 20040724:
+ *   - more tinkering with clobber list at lines 4529 and 5033, to get
+ *     it to compile on gcc-3.4.
+ *
+ * STILL TO DO:
+ *     - test png_do_read_interlace() 64-bit case (pixel_bytes == 8)
+ *     - write MMX code for 48-bit case (pixel_bytes == 6)
+ *     - figure out what's up with 24-bit case (pixel_bytes == 3):
+ *        why subtract 8 from width_mmx in the pass 4/5 case?
+ *        (only width_mmx case) (near line 1606)
+ *     - rewrite all MMX interlacing code so it's aligned with beginning
+ *        of the row buffer, not the end (see 19991007 for details)
+ *     x pick one version of mmxsupport() and get rid of the other
+ *     - add error messages to any remaining bogus default cases
+ *     - enable pixel_depth == 8 cases in png_read_filter_row()? (test speed)
+ *     x add support for runtime enable/disable/query of various MMX routines
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_USE_PNGGCCRD)
+
+int PNGAPI png_mmx_support(void);
+
+#ifdef PNG_USE_LOCAL_ARRAYS
+static const int FARDATA png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+static const int FARDATA png_pass_inc[7]   = {8, 8, 4, 4, 2, 2, 1};
+static const int FARDATA png_pass_width[7] = {8, 4, 4, 2, 2, 1, 1};
+#endif
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+/* djgpp, Win32, and Cygwin add their own underscores to global variables,
+ * so define them without: */
+#if defined(__DJGPP__) || defined(WIN32) || defined(__CYGWIN__)
+#  define _mmx_supported  mmx_supported
+#  define _const4         const4
+#  define _const6         const6
+#  define _mask8_0        mask8_0
+#  define _mask16_1       mask16_1
+#  define _mask16_0       mask16_0
+#  define _mask24_2       mask24_2
+#  define _mask24_1       mask24_1
+#  define _mask24_0       mask24_0
+#  define _mask32_3       mask32_3
+#  define _mask32_2       mask32_2
+#  define _mask32_1       mask32_1
+#  define _mask32_0       mask32_0
+#  define _mask48_5       mask48_5
+#  define _mask48_4       mask48_4
+#  define _mask48_3       mask48_3
+#  define _mask48_2       mask48_2
+#  define _mask48_1       mask48_1
+#  define _mask48_0       mask48_0
+#  define _LBCarryMask    LBCarryMask
+#  define _HBClearMask    HBClearMask
+#  define _ActiveMask     ActiveMask
+#  define _ActiveMask2    ActiveMask2
+#  define _ActiveMaskEnd  ActiveMaskEnd
+#  define _ShiftBpp       ShiftBpp
+#  define _ShiftRem       ShiftRem
+#ifdef PNG_THREAD_UNSAFE_OK
+#  define _unmask         unmask
+#  define _FullLength     FullLength
+#  define _MMXLength      MMXLength
+#  define _dif            dif
+#  define _patemp         patemp
+#  define _pbtemp         pbtemp
+#  define _pctemp         pctemp
+#endif
+#endif
+
+
+/* These constants are used in the inlined MMX assembly code.
+   Ignore gcc's "At top level: defined but not used" warnings. */
+
+/* GRR 20000706:  originally _unmask was needed only when compiling with -fPIC,
+ *  since that case uses the %ebx register for indexing the Global Offset Table
+ *  and there were no other registers available.  But gcc 2.95 and later emit
+ *  "more than 10 operands in `asm'" errors when %ebx is used to preload unmask
+ *  in the non-PIC case, so we'll just use the global unconditionally now.
+ */
+#ifdef PNG_THREAD_UNSAFE_OK
+static int _unmask;
+#endif
+
+static unsigned long long _mask8_0  = 0x0102040810204080LL;
+
+static unsigned long long _mask16_1 = 0x0101020204040808LL;
+static unsigned long long _mask16_0 = 0x1010202040408080LL;
+
+static unsigned long long _mask24_2 = 0x0101010202020404LL;
+static unsigned long long _mask24_1 = 0x0408080810101020LL;
+static unsigned long long _mask24_0 = 0x2020404040808080LL;
+
+static unsigned long long _mask32_3 = 0x0101010102020202LL;
+static unsigned long long _mask32_2 = 0x0404040408080808LL;
+static unsigned long long _mask32_1 = 0x1010101020202020LL;
+static unsigned long long _mask32_0 = 0x4040404080808080LL;
+
+static unsigned long long _mask48_5 = 0x0101010101010202LL;
+static unsigned long long _mask48_4 = 0x0202020204040404LL;
+static unsigned long long _mask48_3 = 0x0404080808080808LL;
+static unsigned long long _mask48_2 = 0x1010101010102020LL;
+static unsigned long long _mask48_1 = 0x2020202040404040LL;
+static unsigned long long _mask48_0 = 0x4040808080808080LL;
+
+static unsigned long long _const4   = 0x0000000000FFFFFFLL;
+//static unsigned long long _const5 = 0x000000FFFFFF0000LL;     // NOT USED
+static unsigned long long _const6   = 0x00000000000000FFLL;
+
+// These are used in the row-filter routines and should/would be local
+//  variables if not for gcc addressing limitations.
+// WARNING: Their presence probably defeats the thread safety of libpng.
+
+#ifdef PNG_THREAD_UNSAFE_OK
+static png_uint_32  _FullLength;
+static png_uint_32  _MMXLength;
+static int          _dif;
+static int          _patemp; // temp variables for Paeth routine
+static int          _pbtemp;
+static int          _pctemp;
+#endif
+
+void /* PRIVATE */
+png_squelch_warnings(void)
+{
+#ifdef PNG_THREAD_UNSAFE_OK
+   _dif = _dif;
+   _patemp = _patemp;
+   _pbtemp = _pbtemp;
+   _pctemp = _pctemp;
+   _MMXLength = _MMXLength;
+#endif
+   _const4  = _const4;
+   _const6  = _const6;
+   _mask8_0  = _mask8_0;
+   _mask16_1 = _mask16_1;
+   _mask16_0 = _mask16_0;
+   _mask24_2 = _mask24_2;
+   _mask24_1 = _mask24_1;
+   _mask24_0 = _mask24_0;
+   _mask32_3 = _mask32_3;
+   _mask32_2 = _mask32_2;
+   _mask32_1 = _mask32_1;
+   _mask32_0 = _mask32_0;
+   _mask48_5 = _mask48_5;
+   _mask48_4 = _mask48_4;
+   _mask48_3 = _mask48_3;
+   _mask48_2 = _mask48_2;
+   _mask48_1 = _mask48_1;
+   _mask48_0 = _mask48_0;
+}
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+
+
+static int _mmx_supported = 2;
+
+/*===========================================================================*/
+/*                                                                           */
+/*                       P N G _ C O M B I N E _ R O W                       */
+/*                                                                           */
+/*===========================================================================*/
+
+#if defined(PNG_HAVE_ASSEMBLER_COMBINE_ROW)
+
+#define BPP2  2
+#define BPP3  3 /* bytes per pixel (a.k.a. pixel_bytes) */
+#define BPP4  4
+#define BPP6  6 /* (defined only to help avoid cut-and-paste errors) */
+#define BPP8  8
+
+/* Combines the row recently read in with the previous row.
+   This routine takes care of alpha and transparency if requested.
+   This routine also handles the two methods of progressive display
+   of interlaced images, depending on the mask value.
+   The mask value describes which pixels are to be combined with
+   the row.  The pattern always repeats every 8 pixels, so just 8
+   bits are needed.  A one indicates the pixel is to be combined; a
+   zero indicates the pixel is to be skipped.  This is in addition
+   to any alpha or transparency value associated with the pixel.
+   If you want all pixels to be combined, pass 0xff (255) in mask. */
+
+/* Use this routine for the x86 platform - it uses a faster MMX routine
+   if the machine supports MMX. */
+
+void /* PRIVATE */
+png_combine_row(png_structp png_ptr, png_bytep row, int mask)
+{
+   png_debug(1, "in png_combine_row (pnggccrd.c)\n");
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+   if (_mmx_supported == 2) {
+#if !defined(PNG_1_0_X)
+       /* this should have happened in png_init_mmx_flags() already */
+       png_warning(png_ptr, "asm_flags may not have been initialized");
+#endif
+       png_mmx_support();
+   }
+#endif
+
+   if (mask == 0xff)
+   {
+      png_debug(2,"mask == 0xff:  doing single png_memcpy()\n");
+      png_memcpy(row, png_ptr->row_buf + 1,
+       (png_size_t)PNG_ROWBYTES(png_ptr->row_info.pixel_depth,png_ptr->width));
+   }
+   else   /* (png_combine_row() is never called with mask == 0) */
+   {
+      switch (png_ptr->row_info.pixel_depth)
+      {
+         case 1:        /* png_ptr->row_info.pixel_depth */
+         {
+            png_bytep sp;
+            png_bytep dp;
+            int s_inc, s_start, s_end;
+            int m;
+            int shift;
+            png_uint_32 i;
+
+            sp = png_ptr->row_buf + 1;
+            dp = row;
+            m = 0x80;
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (png_ptr->transformations & PNG_PACKSWAP)
+            {
+                s_start = 0;
+                s_end = 7;
+                s_inc = 1;
+            }
+            else
+#endif
+            {
+                s_start = 7;
+                s_end = 0;
+                s_inc = -1;
+            }
+
+            shift = s_start;
+
+            for (i = 0; i < png_ptr->width; i++)
+            {
+               if (m & mask)
+               {
+                  int value;
+
+                  value = (*sp >> shift) & 0x1;
+                  *dp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff);
+                  *dp |= (png_byte)(value << shift);
+               }
+
+               if (shift == s_end)
+               {
+                  shift = s_start;
+                  sp++;
+                  dp++;
+               }
+               else
+                  shift += s_inc;
+
+               if (m == 1)
+                  m = 0x80;
+               else
+                  m >>= 1;
+            }
+            break;
+         }
+
+         case 2:        /* png_ptr->row_info.pixel_depth */
+         {
+            png_bytep sp;
+            png_bytep dp;
+            int s_start, s_end, s_inc;
+            int m;
+            int shift;
+            png_uint_32 i;
+            int value;
+
+            sp = png_ptr->row_buf + 1;
+            dp = row;
+            m = 0x80;
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (png_ptr->transformations & PNG_PACKSWAP)
+            {
+               s_start = 0;
+               s_end = 6;
+               s_inc = 2;
+            }
+            else
+#endif
+            {
+               s_start = 6;
+               s_end = 0;
+               s_inc = -2;
+            }
+
+            shift = s_start;
+
+            for (i = 0; i < png_ptr->width; i++)
+            {
+               if (m & mask)
+               {
+                  value = (*sp >> shift) & 0x3;
+                  *dp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
+                  *dp |= (png_byte)(value << shift);
+               }
+
+               if (shift == s_end)
+               {
+                  shift = s_start;
+                  sp++;
+                  dp++;
+               }
+               else
+                  shift += s_inc;
+               if (m == 1)
+                  m = 0x80;
+               else
+                  m >>= 1;
+            }
+            break;
+         }
+
+         case 4:        /* png_ptr->row_info.pixel_depth */
+         {
+            png_bytep sp;
+            png_bytep dp;
+            int s_start, s_end, s_inc;
+            int m;
+            int shift;
+            png_uint_32 i;
+            int value;
+
+            sp = png_ptr->row_buf + 1;
+            dp = row;
+            m = 0x80;
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (png_ptr->transformations & PNG_PACKSWAP)
+            {
+               s_start = 0;
+               s_end = 4;
+               s_inc = 4;
+            }
+            else
+#endif
+            {
+               s_start = 4;
+               s_end = 0;
+               s_inc = -4;
+            }
+            shift = s_start;
+
+            for (i = 0; i < png_ptr->width; i++)
+            {
+               if (m & mask)
+               {
+                  value = (*sp >> shift) & 0xf;
+                  *dp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
+                  *dp |= (png_byte)(value << shift);
+               }
+
+               if (shift == s_end)
+               {
+                  shift = s_start;
+                  sp++;
+                  dp++;
+               }
+               else
+                  shift += s_inc;
+               if (m == 1)
+                  m = 0x80;
+               else
+                  m >>= 1;
+            }
+            break;
+         }
+
+         case 8:        /* png_ptr->row_info.pixel_depth */
+         {
+            png_bytep srcptr;
+            png_bytep dstptr;
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_THREAD_UNSAFE_OK)
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)
+                /* && _mmx_supported */ )
+#else
+            if (_mmx_supported)
+#endif
+            {
+               png_uint_32 len;
+               int diff;
+               int dummy_value_a;   // fix 'forbidden register spilled' error
+               int dummy_value_d;
+               int dummy_value_c;
+               int dummy_value_S;
+               int dummy_value_D;
+               _unmask = ~mask;            // global variable for -fPIC version
+               srcptr = png_ptr->row_buf + 1;
+               dstptr = row;
+               len  = png_ptr->width &~7;  // reduce to multiple of 8
+               diff = (int) (png_ptr->width & 7);  // amount lost
+
+               __asm__ __volatile__ (
+                  "movd      _unmask, %%mm7  \n\t" // load bit pattern
+                  "psubb     %%mm6, %%mm6    \n\t" // zero mm6
+                  "punpcklbw %%mm7, %%mm7    \n\t"
+                  "punpcklwd %%mm7, %%mm7    \n\t"
+                  "punpckldq %%mm7, %%mm7    \n\t" // fill reg with 8 masks
+
+                  "movq      _mask8_0, %%mm0 \n\t"
+                  "pand      %%mm7, %%mm0    \n\t" // nonzero if keep byte
+                  "pcmpeqb   %%mm6, %%mm0    \n\t" // zeros->1s, v versa
+
+// preload        "movl      len, %%ecx      \n\t" // load length of line
+// preload        "movl      srcptr, %%esi   \n\t" // load source
+// preload        "movl      dstptr, %%edi   \n\t" // load dest
+
+                  "cmpl      $0, %%ecx       \n\t" // len == 0 ?
+                  "je        mainloop8end    \n\t"
+
+                "mainloop8:                  \n\t"
+                  "movq      (%%esi), %%mm4  \n\t" // *srcptr
+                  "pand      %%mm0, %%mm4    \n\t"
+                  "movq      %%mm0, %%mm6    \n\t"
+                  "pandn     (%%edi), %%mm6  \n\t" // *dstptr
+                  "por       %%mm6, %%mm4    \n\t"
+                  "movq      %%mm4, (%%edi)  \n\t"
+                  "addl      $8, %%esi       \n\t" // inc by 8 bytes processed
+                  "addl      $8, %%edi       \n\t"
+                  "subl      $8, %%ecx       \n\t" // dec by 8 pixels processed
+                  "ja        mainloop8       \n\t"
+
+                "mainloop8end:               \n\t"
+// preload        "movl      diff, %%ecx     \n\t" // (diff is in eax)
+                  "movl      %%eax, %%ecx    \n\t"
+                  "cmpl      $0, %%ecx       \n\t"
+                  "jz        end8            \n\t"
+// preload        "movl      mask, %%edx     \n\t"
+                  "sall      $24, %%edx      \n\t" // make low byte, high byte
+
+                "secondloop8:                \n\t"
+                  "sall      %%edx           \n\t" // move high bit to CF
+                  "jnc       skip8           \n\t" // if CF = 0
+                  "movb      (%%esi), %%al   \n\t"
+                  "movb      %%al, (%%edi)   \n\t"
+
+                "skip8:                      \n\t"
+                  "incl      %%esi           \n\t"
+                  "incl      %%edi           \n\t"
+                  "decl      %%ecx           \n\t"
+                  "jnz       secondloop8     \n\t"
+
+                "end8:                       \n\t"
+                  "EMMS                      \n\t"  // DONE
+
+                  : "=a" (dummy_value_a),           // output regs (dummy)
+                    "=d" (dummy_value_d),
+                    "=c" (dummy_value_c),
+                    "=S" (dummy_value_S),
+                    "=D" (dummy_value_D)
+
+                  : "3" (srcptr),      // esi       // input regs
+                    "4" (dstptr),      // edi
+                    "0" (diff),        // eax
+// was (unmask)     "b"    RESERVED    // ebx       // Global Offset Table idx
+                    "2" (len),         // ecx
+                    "1" (mask)         // edx
+
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+                  : "%mm0", "%mm4", "%mm6", "%mm7"  // clobber list
+#endif
+               );
+            }
+            else /* mmx _not supported - Use modified C routine */
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+            {
+               register png_uint_32 i;
+               png_uint_32 initial_val = png_pass_start[png_ptr->pass];
+                 /* png.c:  png_pass_start[] = {0, 4, 0, 2, 0, 1, 0}; */
+               register int stride = png_pass_inc[png_ptr->pass];
+                 /* png.c:  png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1}; */
+               register int rep_bytes = png_pass_width[png_ptr->pass];
+                 /* png.c:  png_pass_width[] = {8, 4, 4, 2, 2, 1, 1}; */
+               png_uint_32 len = png_ptr->width &~7;  /* reduce to mult. of 8 */
+               int diff = (int) (png_ptr->width & 7); /* amount lost */
+               register png_uint_32 final_val = len;  /* GRR bugfix */
+
+               srcptr = png_ptr->row_buf + 1 + initial_val;
+               dstptr = row + initial_val;
+
+               for (i = initial_val; i < final_val; i += stride)
+               {
+                  png_memcpy(dstptr, srcptr, rep_bytes);
+                  srcptr += stride;
+                  dstptr += stride;
+               }
+               if (diff)  /* number of leftover pixels:  3 for pngtest */
+               {
+                  final_val+=diff /* *BPP1 */ ;
+                  for (; i < final_val; i += stride)
+                  {
+                     if (rep_bytes > (int)(final_val-i))
+                        rep_bytes = (int)(final_val-i);
+                     png_memcpy(dstptr, srcptr, rep_bytes);
+                     srcptr += stride;
+                     dstptr += stride;
+                  }
+               }
+
+            } /* end of else (_mmx_supported) */
+
+            break;
+         }       /* end 8 bpp */
+
+         case 16:       /* png_ptr->row_info.pixel_depth */
+         {
+            png_bytep srcptr;
+            png_bytep dstptr;
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_THREAD_UNSAFE_OK)
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)
+                /* && _mmx_supported */ )
+#else
+            if (_mmx_supported)
+#endif
+            {
+               png_uint_32 len;
+               int diff;
+               int dummy_value_a;   // fix 'forbidden register spilled' error
+               int dummy_value_d;
+               int dummy_value_c;
+               int dummy_value_S;
+               int dummy_value_D;
+               _unmask = ~mask;            // global variable for -fPIC version
+               srcptr = png_ptr->row_buf + 1;
+               dstptr = row;
+               len  = png_ptr->width &~7;  // reduce to multiple of 8
+               diff = (int) (png_ptr->width & 7); // amount lost //
+
+               __asm__ __volatile__ (
+                  "movd      _unmask, %%mm7   \n\t" // load bit pattern
+                  "psubb     %%mm6, %%mm6     \n\t" // zero mm6
+                  "punpcklbw %%mm7, %%mm7     \n\t"
+                  "punpcklwd %%mm7, %%mm7     \n\t"
+                  "punpckldq %%mm7, %%mm7     \n\t" // fill reg with 8 masks
+
+                  "movq      _mask16_0, %%mm0 \n\t"
+                  "movq      _mask16_1, %%mm1 \n\t"
+
+                  "pand      %%mm7, %%mm0     \n\t"
+                  "pand      %%mm7, %%mm1     \n\t"
+
+                  "pcmpeqb   %%mm6, %%mm0     \n\t"
+                  "pcmpeqb   %%mm6, %%mm1     \n\t"
+
+// preload        "movl      len, %%ecx       \n\t" // load length of line
+// preload        "movl      srcptr, %%esi    \n\t" // load source
+// preload        "movl      dstptr, %%edi    \n\t" // load dest
+
+                  "cmpl      $0, %%ecx        \n\t"
+                  "jz        mainloop16end    \n\t"
+
+                "mainloop16:                  \n\t"
+                  "movq      (%%esi), %%mm4   \n\t"
+                  "pand      %%mm0, %%mm4     \n\t"
+                  "movq      %%mm0, %%mm6     \n\t"
+                  "movq      (%%edi), %%mm7   \n\t"
+                  "pandn     %%mm7, %%mm6     \n\t"
+                  "por       %%mm6, %%mm4     \n\t"
+                  "movq      %%mm4, (%%edi)   \n\t"
+
+                  "movq      8(%%esi), %%mm5  \n\t"
+                  "pand      %%mm1, %%mm5     \n\t"
+                  "movq      %%mm1, %%mm7     \n\t"
+                  "movq      8(%%edi), %%mm6  \n\t"
+                  "pandn     %%mm6, %%mm7     \n\t"
+                  "por       %%mm7, %%mm5     \n\t"
+                  "movq      %%mm5, 8(%%edi)  \n\t"
+
+                  "addl      $16, %%esi       \n\t" // inc by 16 bytes processed
+                  "addl      $16, %%edi       \n\t"
+                  "subl      $8, %%ecx        \n\t" // dec by 8 pixels processed
+                  "ja        mainloop16       \n\t"
+
+                "mainloop16end:               \n\t"
+// preload        "movl      diff, %%ecx      \n\t" // (diff is in eax)
+                  "movl      %%eax, %%ecx     \n\t"
+                  "cmpl      $0, %%ecx        \n\t"
+                  "jz        end16            \n\t"
+// preload        "movl      mask, %%edx      \n\t"
+                  "sall      $24, %%edx       \n\t" // make low byte, high byte
+
+                "secondloop16:                \n\t"
+                  "sall      %%edx            \n\t" // move high bit to CF
+                  "jnc       skip16           \n\t" // if CF = 0
+                  "movw      (%%esi), %%ax    \n\t"
+                  "movw      %%ax, (%%edi)    \n\t"
+
+                "skip16:                      \n\t"
+                  "addl      $2, %%esi        \n\t"
+                  "addl      $2, %%edi        \n\t"
+                  "decl      %%ecx            \n\t"
+                  "jnz       secondloop16     \n\t"
+
+                "end16:                       \n\t"
+                  "EMMS                       \n\t" // DONE
+
+                  : "=a" (dummy_value_a),           // output regs (dummy)
+                    "=c" (dummy_value_c),
+                    "=d" (dummy_value_d),
+                    "=S" (dummy_value_S),
+                    "=D" (dummy_value_D)
+
+                  : "0" (diff),        // eax       // input regs
+// was (unmask)     " "    RESERVED    // ebx       // Global Offset Table idx
+                    "1" (len),         // ecx
+                    "2" (mask),        // edx
+                    "3" (srcptr),      // esi
+                    "4" (dstptr)       // edi
+
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+                  : "%mm0", "%mm1", "%mm4"          // clobber list
+                  , "%mm5", "%mm6", "%mm7"
+#endif
+               );
+            }
+            else /* mmx _not supported - Use modified C routine */
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+            {
+               register png_uint_32 i;
+               png_uint_32 initial_val = BPP2 * png_pass_start[png_ptr->pass];
+                 /* png.c:  png_pass_start[] = {0, 4, 0, 2, 0, 1, 0}; */
+               register int stride = BPP2 * png_pass_inc[png_ptr->pass];
+                 /* png.c:  png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1}; */
+               register int rep_bytes = BPP2 * png_pass_width[png_ptr->pass];
+                 /* png.c:  png_pass_width[] = {8, 4, 4, 2, 2, 1, 1}; */
+               png_uint_32 len = png_ptr->width &~7;  /* reduce to mult. of 8 */
+               int diff = (int) (png_ptr->width & 7); /* amount lost */
+               register png_uint_32 final_val = BPP2 * len;   /* GRR bugfix */
+
+               srcptr = png_ptr->row_buf + 1 + initial_val;
+               dstptr = row + initial_val;
+
+               for (i = initial_val; i < final_val; i += stride)
+               {
+                  png_memcpy(dstptr, srcptr, rep_bytes);
+                  srcptr += stride;
+                  dstptr += stride;
+               }
+               if (diff)  /* number of leftover pixels:  3 for pngtest */
+               {
+                  final_val+=diff*BPP2;
+                  for (; i < final_val; i += stride)
+                  {
+                     if (rep_bytes > (int)(final_val-i))
+                        rep_bytes = (int)(final_val-i);
+                     png_memcpy(dstptr, srcptr, rep_bytes);
+                     srcptr += stride;
+                     dstptr += stride;
+                  }
+               }
+            } /* end of else (_mmx_supported) */
+
+            break;
+         }       /* end 16 bpp */
+
+         case 24:       /* png_ptr->row_info.pixel_depth */
+         {
+            png_bytep srcptr;
+            png_bytep dstptr;
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_THREAD_UNSAFE_OK)
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)
+                /* && _mmx_supported */ )
+#else
+            if (_mmx_supported)
+#endif
+            {
+               png_uint_32 len;
+               int diff;
+               int dummy_value_a;   // fix 'forbidden register spilled' error
+               int dummy_value_d;
+               int dummy_value_c;
+               int dummy_value_S;
+               int dummy_value_D;
+               _unmask = ~mask;            // global variable for -fPIC version
+               srcptr = png_ptr->row_buf + 1;
+               dstptr = row;
+               len  = png_ptr->width &~7;  // reduce to multiple of 8
+               diff = (int) (png_ptr->width & 7); // amount lost //
+
+               __asm__ __volatile__ (
+                  "movd      _unmask, %%mm7   \n\t" // load bit pattern
+                  "psubb     %%mm6, %%mm6     \n\t" // zero mm6
+                  "punpcklbw %%mm7, %%mm7     \n\t"
+                  "punpcklwd %%mm7, %%mm7     \n\t"
+                  "punpckldq %%mm7, %%mm7     \n\t" // fill reg with 8 masks
+
+                  "movq      _mask24_0, %%mm0 \n\t"
+                  "movq      _mask24_1, %%mm1 \n\t"
+                  "movq      _mask24_2, %%mm2 \n\t"
+
+                  "pand      %%mm7, %%mm0     \n\t"
+                  "pand      %%mm7, %%mm1     \n\t"
+                  "pand      %%mm7, %%mm2     \n\t"
+
+                  "pcmpeqb   %%mm6, %%mm0     \n\t"
+                  "pcmpeqb   %%mm6, %%mm1     \n\t"
+                  "pcmpeqb   %%mm6, %%mm2     \n\t"
+
+// preload        "movl      len, %%ecx       \n\t" // load length of line
+// preload        "movl      srcptr, %%esi    \n\t" // load source
+// preload        "movl      dstptr, %%edi    \n\t" // load dest
+
+                  "cmpl      $0, %%ecx        \n\t"
+                  "jz        mainloop24end    \n\t"
+
+                "mainloop24:                  \n\t"
+                  "movq      (%%esi), %%mm4   \n\t"
+                  "pand      %%mm0, %%mm4     \n\t"
+                  "movq      %%mm0, %%mm6     \n\t"
+                  "movq      (%%edi), %%mm7   \n\t"
+                  "pandn     %%mm7, %%mm6     \n\t"
+                  "por       %%mm6, %%mm4     \n\t"
+                  "movq      %%mm4, (%%edi)   \n\t"
+
+                  "movq      8(%%esi), %%mm5  \n\t"
+                  "pand      %%mm1, %%mm5     \n\t"
+                  "movq      %%mm1, %%mm7     \n\t"
+                  "movq      8(%%edi), %%mm6  \n\t"
+                  "pandn     %%mm6, %%mm7     \n\t"
+                  "por       %%mm7, %%mm5     \n\t"
+                  "movq      %%mm5, 8(%%edi)  \n\t"
+
+                  "movq      16(%%esi), %%mm6 \n\t"
+                  "pand      %%mm2, %%mm6     \n\t"
+                  "movq      %%mm2, %%mm4     \n\t"
+                  "movq      16(%%edi), %%mm7 \n\t"
+                  "pandn     %%mm7, %%mm4     \n\t"
+                  "por       %%mm4, %%mm6     \n\t"
+                  "movq      %%mm6, 16(%%edi) \n\t"
+
+                  "addl      $24, %%esi       \n\t" // inc by 24 bytes processed
+                  "addl      $24, %%edi       \n\t"
+                  "subl      $8, %%ecx        \n\t" // dec by 8 pixels processed
+
+                  "ja        mainloop24       \n\t"
+
+                "mainloop24end:               \n\t"
+// preload        "movl      diff, %%ecx      \n\t" // (diff is in eax)
+                  "movl      %%eax, %%ecx     \n\t"
+                  "cmpl      $0, %%ecx        \n\t"
+                  "jz        end24            \n\t"
+// preload        "movl      mask, %%edx      \n\t"
+                  "sall      $24, %%edx       \n\t" // make low byte, high byte
+
+                "secondloop24:                \n\t"
+                  "sall      %%edx            \n\t" // move high bit to CF
+                  "jnc       skip24           \n\t" // if CF = 0
+                  "movw      (%%esi), %%ax    \n\t"
+                  "movw      %%ax, (%%edi)    \n\t"
+                  "xorl      %%eax, %%eax     \n\t"
+                  "movb      2(%%esi), %%al   \n\t"
+                  "movb      %%al, 2(%%edi)   \n\t"
+
+                "skip24:                      \n\t"
+                  "addl      $3, %%esi        \n\t"
+                  "addl      $3, %%edi        \n\t"
+                  "decl      %%ecx            \n\t"
+                  "jnz       secondloop24     \n\t"
+
+                "end24:                       \n\t"
+                  "EMMS                       \n\t" // DONE
+
+                  : "=a" (dummy_value_a),           // output regs (dummy)
+                    "=d" (dummy_value_d),
+                    "=c" (dummy_value_c),
+                    "=S" (dummy_value_S),
+                    "=D" (dummy_value_D)
+
+                  : "3" (srcptr),      // esi       // input regs
+                    "4" (dstptr),      // edi
+                    "0" (diff),        // eax
+// was (unmask)     "b"    RESERVED    // ebx       // Global Offset Table idx
+                    "2" (len),         // ecx
+                    "1" (mask)         // edx
+
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+                  : "%mm0", "%mm1", "%mm2"          // clobber list
+                  , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+               );
+            }
+            else /* mmx _not supported - Use modified C routine */
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+            {
+               register png_uint_32 i;
+               png_uint_32 initial_val = BPP3 * png_pass_start[png_ptr->pass];
+                 /* png.c:  png_pass_start[] = {0, 4, 0, 2, 0, 1, 0}; */
+               register int stride = BPP3 * png_pass_inc[png_ptr->pass];
+                 /* png.c:  png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1}; */
+               register int rep_bytes = BPP3 * png_pass_width[png_ptr->pass];
+                 /* png.c:  png_pass_width[] = {8, 4, 4, 2, 2, 1, 1}; */
+               png_uint_32 len = png_ptr->width &~7;  /* reduce to mult. of 8 */
+               int diff = (int) (png_ptr->width & 7); /* amount lost */
+               register png_uint_32 final_val = BPP3 * len;   /* GRR bugfix */
+
+               srcptr = png_ptr->row_buf + 1 + initial_val;
+               dstptr = row + initial_val;
+
+               for (i = initial_val; i < final_val; i += stride)
+               {
+                  png_memcpy(dstptr, srcptr, rep_bytes);
+                  srcptr += stride;
+                  dstptr += stride;
+               }
+               if (diff)  /* number of leftover pixels:  3 for pngtest */
+               {
+                  final_val+=diff*BPP3;
+                  for (; i < final_val; i += stride)
+                  {
+                     if (rep_bytes > (int)(final_val-i))
+                        rep_bytes = (int)(final_val-i);
+                     png_memcpy(dstptr, srcptr, rep_bytes);
+                     srcptr += stride;
+                     dstptr += stride;
+                  }
+               }
+            } /* end of else (_mmx_supported) */
+
+            break;
+         }       /* end 24 bpp */
+
+         case 32:       /* png_ptr->row_info.pixel_depth */
+         {
+            png_bytep srcptr;
+            png_bytep dstptr;
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_THREAD_UNSAFE_OK)
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)
+                /* && _mmx_supported */ )
+#else
+            if (_mmx_supported)
+#endif
+            {
+               png_uint_32 len;
+               int diff;
+               int dummy_value_a;   // fix 'forbidden register spilled' error
+               int dummy_value_d;
+               int dummy_value_c;
+               int dummy_value_S;
+               int dummy_value_D;
+               _unmask = ~mask;            // global variable for -fPIC version
+               srcptr = png_ptr->row_buf + 1;
+               dstptr = row;
+               len  = png_ptr->width &~7;  // reduce to multiple of 8
+               diff = (int) (png_ptr->width & 7); // amount lost //
+
+               __asm__ __volatile__ (
+                  "movd      _unmask, %%mm7   \n\t" // load bit pattern
+                  "psubb     %%mm6, %%mm6     \n\t" // zero mm6
+                  "punpcklbw %%mm7, %%mm7     \n\t"
+                  "punpcklwd %%mm7, %%mm7     \n\t"
+                  "punpckldq %%mm7, %%mm7     \n\t" // fill reg with 8 masks
+
+                  "movq      _mask32_0, %%mm0 \n\t"
+                  "movq      _mask32_1, %%mm1 \n\t"
+                  "movq      _mask32_2, %%mm2 \n\t"
+                  "movq      _mask32_3, %%mm3 \n\t"
+
+                  "pand      %%mm7, %%mm0     \n\t"
+                  "pand      %%mm7, %%mm1     \n\t"
+                  "pand      %%mm7, %%mm2     \n\t"
+                  "pand      %%mm7, %%mm3     \n\t"
+
+                  "pcmpeqb   %%mm6, %%mm0     \n\t"
+                  "pcmpeqb   %%mm6, %%mm1     \n\t"
+                  "pcmpeqb   %%mm6, %%mm2     \n\t"
+                  "pcmpeqb   %%mm6, %%mm3     \n\t"
+
+// preload        "movl      len, %%ecx       \n\t" // load length of line
+// preload        "movl      srcptr, %%esi    \n\t" // load source
+// preload        "movl      dstptr, %%edi    \n\t" // load dest
+
+                  "cmpl      $0, %%ecx        \n\t" // lcr
+                  "jz        mainloop32end    \n\t"
+
+                "mainloop32:                  \n\t"
+                  "movq      (%%esi), %%mm4   \n\t"
+                  "pand      %%mm0, %%mm4     \n\t"
+                  "movq      %%mm0, %%mm6     \n\t"
+                  "movq      (%%edi), %%mm7   \n\t"
+                  "pandn     %%mm7, %%mm6     \n\t"
+                  "por       %%mm6, %%mm4     \n\t"
+                  "movq      %%mm4, (%%edi)   \n\t"
+
+                  "movq      8(%%esi), %%mm5  \n\t"
+                  "pand      %%mm1, %%mm5     \n\t"
+                  "movq      %%mm1, %%mm7     \n\t"
+                  "movq      8(%%edi), %%mm6  \n\t"
+                  "pandn     %%mm6, %%mm7     \n\t"
+                  "por       %%mm7, %%mm5     \n\t"
+                  "movq      %%mm5, 8(%%edi)  \n\t"
+
+                  "movq      16(%%esi), %%mm6 \n\t"
+                  "pand      %%mm2, %%mm6     \n\t"
+                  "movq      %%mm2, %%mm4     \n\t"
+                  "movq      16(%%edi), %%mm7 \n\t"
+                  "pandn     %%mm7, %%mm4     \n\t"
+                  "por       %%mm4, %%mm6     \n\t"
+                  "movq      %%mm6, 16(%%edi) \n\t"
+
+                  "movq      24(%%esi), %%mm7 \n\t"
+                  "pand      %%mm3, %%mm7     \n\t"
+                  "movq      %%mm3, %%mm5     \n\t"
+                  "movq      24(%%edi), %%mm4 \n\t"
+                  "pandn     %%mm4, %%mm5     \n\t"
+                  "por       %%mm5, %%mm7     \n\t"
+                  "movq      %%mm7, 24(%%edi) \n\t"
+
+                  "addl      $32, %%esi       \n\t" // inc by 32 bytes processed
+                  "addl      $32, %%edi       \n\t"
+                  "subl      $8, %%ecx        \n\t" // dec by 8 pixels processed
+                  "ja        mainloop32       \n\t"
+
+                "mainloop32end:               \n\t"
+// preload        "movl      diff, %%ecx      \n\t" // (diff is in eax)
+                  "movl      %%eax, %%ecx     \n\t"
+                  "cmpl      $0, %%ecx        \n\t"
+                  "jz        end32            \n\t"
+// preload        "movl      mask, %%edx      \n\t"
+                  "sall      $24, %%edx       \n\t" // low byte => high byte
+
+                "secondloop32:                \n\t"
+                  "sall      %%edx            \n\t" // move high bit to CF
+                  "jnc       skip32           \n\t" // if CF = 0
+                  "movl      (%%esi), %%eax   \n\t"
+                  "movl      %%eax, (%%edi)   \n\t"
+
+                "skip32:                      \n\t"
+                  "addl      $4, %%esi        \n\t"
+                  "addl      $4, %%edi        \n\t"
+                  "decl      %%ecx            \n\t"
+                  "jnz       secondloop32     \n\t"
+
+                "end32:                       \n\t"
+                  "EMMS                       \n\t" // DONE
+
+                  : "=a" (dummy_value_a),           // output regs (dummy)
+                    "=d" (dummy_value_d),
+                    "=c" (dummy_value_c),
+                    "=S" (dummy_value_S),
+                    "=D" (dummy_value_D)
+
+                  : "3" (srcptr),      // esi       // input regs
+                    "4" (dstptr),      // edi
+                    "0" (diff),        // eax
+// was (unmask)     "b"    RESERVED    // ebx       // Global Offset Table idx
+                    "2" (len),         // ecx
+                    "1" (mask)         // edx
+
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+                  : "%mm0", "%mm1", "%mm2", "%mm3"  // clobber list
+                  , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+               );
+            }
+            else /* mmx _not supported - Use modified C routine */
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+            {
+               register png_uint_32 i;
+               png_uint_32 initial_val = BPP4 * png_pass_start[png_ptr->pass];
+                 /* png.c:  png_pass_start[] = {0, 4, 0, 2, 0, 1, 0}; */
+               register int stride = BPP4 * png_pass_inc[png_ptr->pass];
+                 /* png.c:  png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1}; */
+               register int rep_bytes = BPP4 * png_pass_width[png_ptr->pass];
+                 /* png.c:  png_pass_width[] = {8, 4, 4, 2, 2, 1, 1}; */
+               png_uint_32 len = png_ptr->width &~7;  /* reduce to mult. of 8 */
+               int diff = (int) (png_ptr->width & 7); /* amount lost */
+               register png_uint_32 final_val = BPP4 * len;   /* GRR bugfix */
+
+               srcptr = png_ptr->row_buf + 1 + initial_val;
+               dstptr = row + initial_val;
+
+               for (i = initial_val; i < final_val; i += stride)
+               {
+                  png_memcpy(dstptr, srcptr, rep_bytes);
+                  srcptr += stride;
+                  dstptr += stride;
+               }
+               if (diff)  /* number of leftover pixels:  3 for pngtest */
+               {
+                  final_val+=diff*BPP4;
+                  for (; i < final_val; i += stride)
+                  {
+                     if (rep_bytes > (int)(final_val-i))
+                        rep_bytes = (int)(final_val-i);
+                     png_memcpy(dstptr, srcptr, rep_bytes);
+                     srcptr += stride;
+                     dstptr += stride;
+                  }
+               }
+            } /* end of else (_mmx_supported) */
+
+            break;
+         }       /* end 32 bpp */
+
+         case 48:       /* png_ptr->row_info.pixel_depth */
+         {
+            png_bytep srcptr;
+            png_bytep dstptr;
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_THREAD_UNSAFE_OK)
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)
+                /* && _mmx_supported */ )
+#else
+            if (_mmx_supported)
+#endif
+            {
+               png_uint_32 len;
+               int diff;
+               int dummy_value_a;   // fix 'forbidden register spilled' error
+               int dummy_value_d;
+               int dummy_value_c;
+               int dummy_value_S;
+               int dummy_value_D;
+               _unmask = ~mask;            // global variable for -fPIC version
+               srcptr = png_ptr->row_buf + 1;
+               dstptr = row;
+               len  = png_ptr->width &~7;  // reduce to multiple of 8
+               diff = (int) (png_ptr->width & 7); // amount lost //
+
+               __asm__ __volatile__ (
+                  "movd      _unmask, %%mm7   \n\t" // load bit pattern
+                  "psubb     %%mm6, %%mm6     \n\t" // zero mm6
+                  "punpcklbw %%mm7, %%mm7     \n\t"
+                  "punpcklwd %%mm7, %%mm7     \n\t"
+                  "punpckldq %%mm7, %%mm7     \n\t" // fill reg with 8 masks
+
+                  "movq      _mask48_0, %%mm0 \n\t"
+                  "movq      _mask48_1, %%mm1 \n\t"
+                  "movq      _mask48_2, %%mm2 \n\t"
+                  "movq      _mask48_3, %%mm3 \n\t"
+                  "movq      _mask48_4, %%mm4 \n\t"
+                  "movq      _mask48_5, %%mm5 \n\t"
+
+                  "pand      %%mm7, %%mm0     \n\t"
+                  "pand      %%mm7, %%mm1     \n\t"
+                  "pand      %%mm7, %%mm2     \n\t"
+                  "pand      %%mm7, %%mm3     \n\t"
+                  "pand      %%mm7, %%mm4     \n\t"
+                  "pand      %%mm7, %%mm5     \n\t"
+
+                  "pcmpeqb   %%mm6, %%mm0     \n\t"
+                  "pcmpeqb   %%mm6, %%mm1     \n\t"
+                  "pcmpeqb   %%mm6, %%mm2     \n\t"
+                  "pcmpeqb   %%mm6, %%mm3     \n\t"
+                  "pcmpeqb   %%mm6, %%mm4     \n\t"
+                  "pcmpeqb   %%mm6, %%mm5     \n\t"
+
+// preload        "movl      len, %%ecx       \n\t" // load length of line
+// preload        "movl      srcptr, %%esi    \n\t" // load source
+// preload        "movl      dstptr, %%edi    \n\t" // load dest
+
+                  "cmpl      $0, %%ecx        \n\t"
+                  "jz        mainloop48end    \n\t"
+
+                "mainloop48:                  \n\t"
+                  "movq      (%%esi), %%mm7   \n\t"
+                  "pand      %%mm0, %%mm7     \n\t"
+                  "movq      %%mm0, %%mm6     \n\t"
+                  "pandn     (%%edi), %%mm6   \n\t"
+                  "por       %%mm6, %%mm7     \n\t"
+                  "movq      %%mm7, (%%edi)   \n\t"
+
+                  "movq      8(%%esi), %%mm6  \n\t"
+                  "pand      %%mm1, %%mm6     \n\t"
+                  "movq      %%mm1, %%mm7     \n\t"
+                  "pandn     8(%%edi), %%mm7  \n\t"
+                  "por       %%mm7, %%mm6     \n\t"
+                  "movq      %%mm6, 8(%%edi)  \n\t"
+
+                  "movq      16(%%esi), %%mm6 \n\t"
+                  "pand      %%mm2, %%mm6     \n\t"
+                  "movq      %%mm2, %%mm7     \n\t"
+                  "pandn     16(%%edi), %%mm7 \n\t"
+                  "por       %%mm7, %%mm6     \n\t"
+                  "movq      %%mm6, 16(%%edi) \n\t"
+
+                  "movq      24(%%esi), %%mm7 \n\t"
+                  "pand      %%mm3, %%mm7     \n\t"
+                  "movq      %%mm3, %%mm6     \n\t"
+                  "pandn     24(%%edi), %%mm6 \n\t"
+                  "por       %%mm6, %%mm7     \n\t"
+                  "movq      %%mm7, 24(%%edi) \n\t"
+
+                  "movq      32(%%esi), %%mm6 \n\t"
+                  "pand      %%mm4, %%mm6     \n\t"
+                  "movq      %%mm4, %%mm7     \n\t"
+                  "pandn     32(%%edi), %%mm7 \n\t"
+                  "por       %%mm7, %%mm6     \n\t"
+                  "movq      %%mm6, 32(%%edi) \n\t"
+
+                  "movq      40(%%esi), %%mm7 \n\t"
+                  "pand      %%mm5, %%mm7     \n\t"
+                  "movq      %%mm5, %%mm6     \n\t"
+                  "pandn     40(%%edi), %%mm6 \n\t"
+                  "por       %%mm6, %%mm7     \n\t"
+                  "movq      %%mm7, 40(%%edi) \n\t"
+
+                  "addl      $48, %%esi       \n\t" // inc by 48 bytes processed
+                  "addl      $48, %%edi       \n\t"
+                  "subl      $8, %%ecx        \n\t" // dec by 8 pixels processed
+
+                  "ja        mainloop48       \n\t"
+
+                "mainloop48end:               \n\t"
+// preload        "movl      diff, %%ecx      \n\t" // (diff is in eax)
+                  "movl      %%eax, %%ecx     \n\t"
+                  "cmpl      $0, %%ecx        \n\t"
+                  "jz        end48            \n\t"
+// preload        "movl      mask, %%edx      \n\t"
+                  "sall      $24, %%edx       \n\t" // make low byte, high byte
+
+                "secondloop48:                \n\t"
+                  "sall      %%edx            \n\t" // move high bit to CF
+                  "jnc       skip48           \n\t" // if CF = 0
+                  "movl      (%%esi), %%eax   \n\t"
+                  "movl      %%eax, (%%edi)   \n\t"
+
+                "skip48:                      \n\t"
+                  "addl      $4, %%esi        \n\t"
+                  "addl      $4, %%edi        \n\t"
+                  "decl      %%ecx            \n\t"
+                  "jnz       secondloop48     \n\t"
+
+                "end48:                       \n\t"
+                  "EMMS                       \n\t" // DONE
+
+                  : "=a" (dummy_value_a),           // output regs (dummy)
+                    "=d" (dummy_value_d),
+                    "=c" (dummy_value_c),
+                    "=S" (dummy_value_S),
+                    "=D" (dummy_value_D)
+
+                  : "3" (srcptr),      // esi       // input regs
+                    "4" (dstptr),      // edi
+                    "0" (diff),        // eax
+// was (unmask)     "b"    RESERVED    // ebx       // Global Offset Table idx
+                    "2" (len),         // ecx
+                    "1" (mask)         // edx
+
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+                  : "%mm0", "%mm1", "%mm2", "%mm3"  // clobber list
+                  , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+               );
+            }
+            else /* mmx _not supported - Use modified C routine */
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+            {
+               register png_uint_32 i;
+               png_uint_32 initial_val = BPP6 * png_pass_start[png_ptr->pass];
+                 /* png.c:  png_pass_start[] = {0, 4, 0, 2, 0, 1, 0}; */
+               register int stride = BPP6 * png_pass_inc[png_ptr->pass];
+                 /* png.c:  png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1}; */
+               register int rep_bytes = BPP6 * png_pass_width[png_ptr->pass];
+                 /* png.c:  png_pass_width[] = {8, 4, 4, 2, 2, 1, 1}; */
+               png_uint_32 len = png_ptr->width &~7;  /* reduce to mult. of 8 */
+               int diff = (int) (png_ptr->width & 7); /* amount lost */
+               register png_uint_32 final_val = BPP6 * len;   /* GRR bugfix */
+
+               srcptr = png_ptr->row_buf + 1 + initial_val;
+               dstptr = row + initial_val;
+
+               for (i = initial_val; i < final_val; i += stride)
+               {
+                  png_memcpy(dstptr, srcptr, rep_bytes);
+                  srcptr += stride;
+                  dstptr += stride;
+               }
+               if (diff)  /* number of leftover pixels:  3 for pngtest */
+               {
+                  final_val+=diff*BPP6;
+                  for (; i < final_val; i += stride)
+                  {
+                     if (rep_bytes > (int)(final_val-i))
+                        rep_bytes = (int)(final_val-i);
+                     png_memcpy(dstptr, srcptr, rep_bytes);
+                     srcptr += stride;
+                     dstptr += stride;
+                  }
+               }
+            } /* end of else (_mmx_supported) */
+
+            break;
+         }       /* end 48 bpp */
+
+         case 64:       /* png_ptr->row_info.pixel_depth */
+         {
+            png_bytep srcptr;
+            png_bytep dstptr;
+            register png_uint_32 i;
+            png_uint_32 initial_val = BPP8 * png_pass_start[png_ptr->pass];
+              /* png.c:  png_pass_start[] = {0, 4, 0, 2, 0, 1, 0}; */
+            register int stride = BPP8 * png_pass_inc[png_ptr->pass];
+              /* png.c:  png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1}; */
+            register int rep_bytes = BPP8 * png_pass_width[png_ptr->pass];
+              /* png.c:  png_pass_width[] = {8, 4, 4, 2, 2, 1, 1}; */
+            png_uint_32 len = png_ptr->width &~7;  /* reduce to mult. of 8 */
+            int diff = (int) (png_ptr->width & 7); /* amount lost */
+            register png_uint_32 final_val = BPP8 * len;   /* GRR bugfix */
+
+            srcptr = png_ptr->row_buf + 1 + initial_val;
+            dstptr = row + initial_val;
+
+            for (i = initial_val; i < final_val; i += stride)
+            {
+               png_memcpy(dstptr, srcptr, rep_bytes);
+               srcptr += stride;
+               dstptr += stride;
+            }
+            if (diff)  /* number of leftover pixels:  3 for pngtest */
+            {
+               final_val+=diff*BPP8;
+               for (; i < final_val; i += stride)
+               {
+                  if (rep_bytes > (int)(final_val-i))
+                     rep_bytes = (int)(final_val-i);
+                  png_memcpy(dstptr, srcptr, rep_bytes);
+                  srcptr += stride;
+                  dstptr += stride;
+               }
+            }
+
+            break;
+         }       /* end 64 bpp */
+
+         default: /* png_ptr->row_info.pixel_depth != 1,2,4,8,16,24,32,48,64 */
+         {
+            /* this should never happen */
+            png_warning(png_ptr, "Invalid row_info.pixel_depth in pnggccrd");
+            break;
+         }
+      } /* end switch (png_ptr->row_info.pixel_depth) */
+
+   } /* end if (non-trivial mask) */
+
+} /* end png_combine_row() */
+
+#endif /* PNG_HAVE_ASSEMBLER_COMBINE_ROW */
+
+
+
+
+/*===========================================================================*/
+/*                                                                           */
+/*                 P N G _ D O _ R E A D _ I N T E R L A C E                 */
+/*                                                                           */
+/*===========================================================================*/
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+#if defined(PNG_HAVE_ASSEMBLER_READ_INTERLACE)
+
+/* png_do_read_interlace() is called after any 16-bit to 8-bit conversion
+ * has taken place.  [GRR: what other steps come before and/or after?]
+ */
+
+void /* PRIVATE */
+png_do_read_interlace(png_structp png_ptr)
+{
+   png_row_infop row_info = &(png_ptr->row_info);
+   png_bytep row = png_ptr->row_buf + 1;
+   int pass = png_ptr->pass;
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+   png_uint_32 transformations = png_ptr->transformations;
+#endif
+
+   png_debug(1, "in png_do_read_interlace (pnggccrd.c)\n");
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+   if (_mmx_supported == 2) {
+#if !defined(PNG_1_0_X)
+       /* this should have happened in png_init_mmx_flags() already */
+       png_warning(png_ptr, "asm_flags may not have been initialized");
+#endif
+       png_mmx_support();
+   }
+#endif
+
+   if (row != NULL && row_info != NULL)
+   {
+      png_uint_32 final_width;
+
+      final_width = row_info->width * png_pass_inc[pass];
+
+      switch (row_info->pixel_depth)
+      {
+         case 1:
+         {
+            png_bytep sp, dp;
+            int sshift, dshift;
+            int s_start, s_end, s_inc;
+            png_byte v;
+            png_uint_32 i;
+            int j;
+
+            sp = row + (png_size_t)((row_info->width - 1) >> 3);
+            dp = row + (png_size_t)((final_width - 1) >> 3);
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (transformations & PNG_PACKSWAP)
+            {
+               sshift = (int)((row_info->width + 7) & 7);
+               dshift = (int)((final_width + 7) & 7);
+               s_start = 7;
+               s_end = 0;
+               s_inc = -1;
+            }
+            else
+#endif
+            {
+               sshift = 7 - (int)((row_info->width + 7) & 7);
+               dshift = 7 - (int)((final_width + 7) & 7);
+               s_start = 0;
+               s_end = 7;
+               s_inc = 1;
+            }
+
+            for (i = row_info->width; i; i--)
+            {
+               v = (png_byte)((*sp >> sshift) & 0x1);
+               for (j = 0; j < png_pass_inc[pass]; j++)
+               {
+                  *dp &= (png_byte)((0x7f7f >> (7 - dshift)) & 0xff);
+                  *dp |= (png_byte)(v << dshift);
+                  if (dshift == s_end)
+                  {
+                     dshift = s_start;
+                     dp--;
+                  }
+                  else
+                     dshift += s_inc;
+               }
+               if (sshift == s_end)
+               {
+                  sshift = s_start;
+                  sp--;
+               }
+               else
+                  sshift += s_inc;
+            }
+            break;
+         }
+
+         case 2:
+         {
+            png_bytep sp, dp;
+            int sshift, dshift;
+            int s_start, s_end, s_inc;
+            png_uint_32 i;
+
+            sp = row + (png_size_t)((row_info->width - 1) >> 2);
+            dp = row + (png_size_t)((final_width - 1) >> 2);
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (transformations & PNG_PACKSWAP)
+            {
+               sshift = (png_size_t)(((row_info->width + 3) & 3) << 1);
+               dshift = (png_size_t)(((final_width + 3) & 3) << 1);
+               s_start = 6;
+               s_end = 0;
+               s_inc = -2;
+            }
+            else
+#endif
+            {
+               sshift = (png_size_t)((3 - ((row_info->width + 3) & 3)) << 1);
+               dshift = (png_size_t)((3 - ((final_width + 3) & 3)) << 1);
+               s_start = 0;
+               s_end = 6;
+               s_inc = 2;
+            }
+
+            for (i = row_info->width; i; i--)
+            {
+               png_byte v;
+               int j;
+
+               v = (png_byte)((*sp >> sshift) & 0x3);
+               for (j = 0; j < png_pass_inc[pass]; j++)
+               {
+                  *dp &= (png_byte)((0x3f3f >> (6 - dshift)) & 0xff);
+                  *dp |= (png_byte)(v << dshift);
+                  if (dshift == s_end)
+                  {
+                     dshift = s_start;
+                     dp--;
+                  }
+                  else
+                     dshift += s_inc;
+               }
+               if (sshift == s_end)
+               {
+                  sshift = s_start;
+                  sp--;
+               }
+               else
+                  sshift += s_inc;
+            }
+            break;
+         }
+
+         case 4:
+         {
+            png_bytep sp, dp;
+            int sshift, dshift;
+            int s_start, s_end, s_inc;
+            png_uint_32 i;
+
+            sp = row + (png_size_t)((row_info->width - 1) >> 1);
+            dp = row + (png_size_t)((final_width - 1) >> 1);
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (transformations & PNG_PACKSWAP)
+            {
+               sshift = (png_size_t)(((row_info->width + 1) & 1) << 2);
+               dshift = (png_size_t)(((final_width + 1) & 1) << 2);
+               s_start = 4;
+               s_end = 0;
+               s_inc = -4;
+            }
+            else
+#endif
+            {
+               sshift = (png_size_t)((1 - ((row_info->width + 1) & 1)) << 2);
+               dshift = (png_size_t)((1 - ((final_width + 1) & 1)) << 2);
+               s_start = 0;
+               s_end = 4;
+               s_inc = 4;
+            }
+
+            for (i = row_info->width; i; i--)
+            {
+               png_byte v;
+               int j;
+
+               v = (png_byte)((*sp >> sshift) & 0xf);
+               for (j = 0; j < png_pass_inc[pass]; j++)
+               {
+                  *dp &= (png_byte)((0xf0f >> (4 - dshift)) & 0xff);
+                  *dp |= (png_byte)(v << dshift);
+                  if (dshift == s_end)
+                  {
+                     dshift = s_start;
+                     dp--;
+                  }
+                  else
+                     dshift += s_inc;
+               }
+               if (sshift == s_end)
+               {
+                  sshift = s_start;
+                  sp--;
+               }
+               else
+                  sshift += s_inc;
+            }
+            break;
+         }
+
+       /*====================================================================*/
+
+         default: /* 8-bit or larger (this is where the routine is modified) */
+         {
+#if 0
+//          static unsigned long long _const4 = 0x0000000000FFFFFFLL;  no good
+//          static unsigned long long const4 = 0x0000000000FFFFFFLL;   no good
+//          unsigned long long _const4 = 0x0000000000FFFFFFLL;         no good
+//          unsigned long long const4 = 0x0000000000FFFFFFLL;          no good
+#endif
+            png_bytep sptr, dp;
+            png_uint_32 i;
+            png_size_t pixel_bytes;
+            int width = (int)row_info->width;
+
+            pixel_bytes = (row_info->pixel_depth >> 3);
+
+            /* point sptr at the last pixel in the pre-expanded row: */
+            sptr = row + (width - 1) * pixel_bytes;
+
+            /* point dp at the last pixel position in the expanded row: */
+            dp = row + (final_width - 1) * pixel_bytes;
+
+            /* New code by Nirav Chhatrapati - Intel Corporation */
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_INTERLACE)
+                /* && _mmx_supported */ )
+#else
+            if (_mmx_supported)
+#endif
+            {
+               //--------------------------------------------------------------
+               if (pixel_bytes == 3)
+               {
+                  if (((pass == 0) || (pass == 1)) && width)
+                  {
+                     int dummy_value_c;   // fix 'forbidden register spilled'
+                     int dummy_value_S;
+                     int dummy_value_D;
+
+                     __asm__ __volatile__ (
+                        "subl $21, %%edi         \n\t"
+                                     // (png_pass_inc[pass] - 1)*pixel_bytes
+
+                     ".loop3_pass0:              \n\t"
+                        "movd (%%esi), %%mm0     \n\t" // x x x x x 2 1 0
+                        "pand _const4, %%mm0     \n\t" // z z z z z 2 1 0
+                        "movq %%mm0, %%mm1       \n\t" // z z z z z 2 1 0
+                        "psllq $16, %%mm0        \n\t" // z z z 2 1 0 z z
+                        "movq %%mm0, %%mm2       \n\t" // z z z 2 1 0 z z
+                        "psllq $24, %%mm0        \n\t" // 2 1 0 z z z z z
+                        "psrlq $8, %%mm1         \n\t" // z z z z z z 2 1
+                        "por %%mm2, %%mm0        \n\t" // 2 1 0 2 1 0 z z
+                        "por %%mm1, %%mm0        \n\t" // 2 1 0 2 1 0 2 1
+                        "movq %%mm0, %%mm3       \n\t" // 2 1 0 2 1 0 2 1
+                        "psllq $16, %%mm0        \n\t" // 0 2 1 0 2 1 z z
+                        "movq %%mm3, %%mm4       \n\t" // 2 1 0 2 1 0 2 1
+                        "punpckhdq %%mm0, %%mm3  \n\t" // 0 2 1 0 2 1 0 2
+                        "movq %%mm4, 16(%%edi)   \n\t"
+                        "psrlq $32, %%mm0        \n\t" // z z z z 0 2 1 0
+                        "movq %%mm3, 8(%%edi)    \n\t"
+                        "punpckldq %%mm4, %%mm0  \n\t" // 1 0 2 1 0 2 1 0
+                        "subl $3, %%esi          \n\t"
+                        "movq %%mm0, (%%edi)     \n\t"
+                        "subl $24, %%edi         \n\t"
+                        "decl %%ecx              \n\t"
+                        "jnz .loop3_pass0        \n\t"
+                        "EMMS                    \n\t" // DONE
+
+                        : "=c" (dummy_value_c),        // output regs (dummy)
+                          "=S" (dummy_value_S),
+                          "=D" (dummy_value_D)
+
+                        : "1" (sptr),      // esi      // input regs
+                          "2" (dp),        // edi
+                          "0" (width),     // ecx
+                          "rim" (_const4)  // %1(?)  (0x0000000000FFFFFFLL)
+
+#if 0  /* %mm0, ..., %mm4 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                        : "%mm0", "%mm1", "%mm2"       // clobber list
+                        , "%mm3", "%mm4"
+#endif
+                     );
+                  }
+                  else if (((pass == 2) || (pass == 3)) && width)
+                  {
+                     int dummy_value_c;   // fix 'forbidden register spilled'
+                     int dummy_value_S;
+                     int dummy_value_D;
+
+                     __asm__ __volatile__ (
+                        "subl $9, %%edi          \n\t"
+                                     // (png_pass_inc[pass] - 1)*pixel_bytes
+
+                     ".loop3_pass2:              \n\t"
+                        "movd (%%esi), %%mm0     \n\t" // x x x x x 2 1 0
+                        "pand _const4, %%mm0     \n\t" // z z z z z 2 1 0
+                        "movq %%mm0, %%mm1       \n\t" // z z z z z 2 1 0
+                        "psllq $16, %%mm0        \n\t" // z z z 2 1 0 z z
+                        "movq %%mm0, %%mm2       \n\t" // z z z 2 1 0 z z
+                        "psllq $24, %%mm0        \n\t" // 2 1 0 z z z z z
+                        "psrlq $8, %%mm1         \n\t" // z z z z z z 2 1
+                        "por %%mm2, %%mm0        \n\t" // 2 1 0 2 1 0 z z
+                        "por %%mm1, %%mm0        \n\t" // 2 1 0 2 1 0 2 1
+                        "movq %%mm0, 4(%%edi)    \n\t"
+                        "psrlq $16, %%mm0        \n\t" // z z 2 1 0 2 1 0
+                        "subl $3, %%esi          \n\t"
+                        "movd %%mm0, (%%edi)     \n\t"
+                        "subl $12, %%edi         \n\t"
+                        "decl %%ecx              \n\t"
+                        "jnz .loop3_pass2        \n\t"
+                        "EMMS                    \n\t" // DONE
+
+                        : "=c" (dummy_value_c),        // output regs (dummy)
+                          "=S" (dummy_value_S),
+                          "=D" (dummy_value_D)
+
+                        : "1" (sptr),      // esi      // input regs
+                          "2" (dp),        // edi
+                          "0" (width),     // ecx
+                          "rim" (_const4)  // (0x0000000000FFFFFFLL)
+
+#if 0  /* %mm0, ..., %mm2 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                        : "%mm0", "%mm1", "%mm2"       // clobber list
+#endif
+                     );
+                  }
+                  else if (width) /* && ((pass == 4) || (pass == 5)) */
+                  {
+                     int width_mmx = ((width >> 1) << 1) - 8;   // GRR:  huh?
+                     if (width_mmx < 0)
+                         width_mmx = 0;
+                     width -= width_mmx;        // 8 or 9 pix, 24 or 27 bytes
+                     if (width_mmx)
+                     {
+                        // png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
+                        // sptr points at last pixel in pre-expanded row
+                        // dp points at last pixel position in expanded row
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $3, %%esi          \n\t"
+                           "subl $9, %%edi          \n\t"
+                                        // (png_pass_inc[pass] + 1)*pixel_bytes
+
+                        ".loop3_pass4:              \n\t"
+                           "movq (%%esi), %%mm0     \n\t" // x x 5 4 3 2 1 0
+                           "movq %%mm0, %%mm1       \n\t" // x x 5 4 3 2 1 0
+                           "movq %%mm0, %%mm2       \n\t" // x x 5 4 3 2 1 0
+                           "psllq $24, %%mm0        \n\t" // 4 3 2 1 0 z z z
+                           "pand _const4, %%mm1     \n\t" // z z z z z 2 1 0
+                           "psrlq $24, %%mm2        \n\t" // z z z x x 5 4 3
+                           "por %%mm1, %%mm0        \n\t" // 4 3 2 1 0 2 1 0
+                           "movq %%mm2, %%mm3       \n\t" // z z z x x 5 4 3
+                           "psllq $8, %%mm2         \n\t" // z z x x 5 4 3 z
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "psrlq $16, %%mm3        \n\t" // z z z z z x x 5
+                           "pand _const6, %%mm3     \n\t" // z z z z z z z 5
+                           "por %%mm3, %%mm2        \n\t" // z z x x 5 4 3 5
+                           "subl $6, %%esi          \n\t"
+                           "movd %%mm2, 8(%%edi)    \n\t"
+                           "subl $12, %%edi         \n\t"
+                           "subl $2, %%ecx          \n\t"
+                           "jnz .loop3_pass4        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (dummy)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width_mmx), // ecx
+                             "rim" (_const4), // 0x0000000000FFFFFFLL
+                             "rim" (_const6)  // 0x00000000000000FFLL
+
+#if 0  /* %mm0, ..., %mm3 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0", "%mm1"               // clobber list
+                           , "%mm2", "%mm3"
+#endif
+                        );
+                     }
+
+                     sptr -= width_mmx*3;
+                     dp -= width_mmx*6;
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+
+                        png_memcpy(v, sptr, 3);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           png_memcpy(dp, v, 3);
+                           dp -= 3;
+                        }
+                        sptr -= 3;
+                     }
+                  }
+               } /* end of pixel_bytes == 3 */
+
+               //--------------------------------------------------------------
+               else if (pixel_bytes == 1)
+               {
+                  if (((pass == 0) || (pass == 1)) && width)
+                  {
+                     int width_mmx = ((width >> 2) << 2);
+                     width -= width_mmx;        // 0-3 pixels => 0-3 bytes
+                     if (width_mmx)
+                     {
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $3, %%esi          \n\t"
+                           "subl $31, %%edi         \n\t"
+
+                        ".loop1_pass0:              \n\t"
+                           "movd (%%esi), %%mm0     \n\t" // x x x x 3 2 1 0
+                           "movq %%mm0, %%mm1       \n\t" // x x x x 3 2 1 0
+                           "punpcklbw %%mm0, %%mm0  \n\t" // 3 3 2 2 1 1 0 0
+                           "movq %%mm0, %%mm2       \n\t" // 3 3 2 2 1 1 0 0
+                           "punpcklwd %%mm0, %%mm0  \n\t" // 1 1 1 1 0 0 0 0
+                           "movq %%mm0, %%mm3       \n\t" // 1 1 1 1 0 0 0 0
+                           "punpckldq %%mm0, %%mm0  \n\t" // 0 0 0 0 0 0 0 0
+                           "punpckhdq %%mm3, %%mm3  \n\t" // 1 1 1 1 1 1 1 1
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "punpckhwd %%mm2, %%mm2  \n\t" // 3 3 3 3 2 2 2 2
+                           "movq %%mm3, 8(%%edi)    \n\t"
+                           "movq %%mm2, %%mm4       \n\t" // 3 3 3 3 2 2 2 2
+                           "punpckldq %%mm2, %%mm2  \n\t" // 2 2 2 2 2 2 2 2
+                           "punpckhdq %%mm4, %%mm4  \n\t" // 3 3 3 3 3 3 3 3
+                           "movq %%mm2, 16(%%edi)   \n\t"
+                           "subl $4, %%esi          \n\t"
+                           "movq %%mm4, 24(%%edi)   \n\t"
+                           "subl $32, %%edi         \n\t"
+                           "subl $4, %%ecx          \n\t"
+                           "jnz .loop1_pass0        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (dummy)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width_mmx)  // ecx
+
+#if 0  /* %mm0, ..., %mm4 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0", "%mm1", "%mm2"       // clobber list
+                           , "%mm3", "%mm4"
+#endif
+                        );
+                     }
+
+                     sptr -= width_mmx;
+                     dp -= width_mmx*8;
+                     for (i = width; i; i--)
+                     {
+                        int j;
+
+                       /* I simplified this part in version 1.0.4e
+                        * here and in several other instances where
+                        * pixel_bytes == 1  -- GR-P
+                        *
+                        * Original code:
+                        *
+                        * png_byte v[8];
+                        * png_memcpy(v, sptr, pixel_bytes);
+                        * for (j = 0; j < png_pass_inc[pass]; j++)
+                        * {
+                        *    png_memcpy(dp, v, pixel_bytes);
+                        *    dp -= pixel_bytes;
+                        * }
+                        * sptr -= pixel_bytes;
+                        *
+                        * Replacement code is in the next three lines:
+                        */
+
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           *dp-- = *sptr;
+                        }
+                        --sptr;
+                     }
+                  }
+                  else if (((pass == 2) || (pass == 3)) && width)
+                  {
+                     int width_mmx = ((width >> 2) << 2);
+                     width -= width_mmx;        // 0-3 pixels => 0-3 bytes
+                     if (width_mmx)
+                     {
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $3, %%esi          \n\t"
+                           "subl $15, %%edi         \n\t"
+
+                        ".loop1_pass2:              \n\t"
+                           "movd (%%esi), %%mm0     \n\t" // x x x x 3 2 1 0
+                           "punpcklbw %%mm0, %%mm0  \n\t" // 3 3 2 2 1 1 0 0
+                           "movq %%mm0, %%mm1       \n\t" // 3 3 2 2 1 1 0 0
+                           "punpcklwd %%mm0, %%mm0  \n\t" // 1 1 1 1 0 0 0 0
+                           "punpckhwd %%mm1, %%mm1  \n\t" // 3 3 3 3 2 2 2 2
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "subl $4, %%esi          \n\t"
+                           "movq %%mm1, 8(%%edi)    \n\t"
+                           "subl $16, %%edi         \n\t"
+                           "subl $4, %%ecx          \n\t"
+                           "jnz .loop1_pass2        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (dummy)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width_mmx)  // ecx
+
+#if 0  /* %mm0, %mm1 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0", "%mm1"               // clobber list
+#endif
+                        );
+                     }
+
+                     sptr -= width_mmx;
+                     dp -= width_mmx*4;
+                     for (i = width; i; i--)
+                     {
+                        int j;
+
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           *dp-- = *sptr;
+                        }
+                        --sptr;
+                     }
+                  }
+                  else if (width)  /* && ((pass == 4) || (pass == 5)) */
+                  {
+                     int width_mmx = ((width >> 3) << 3);
+                     width -= width_mmx;        // 0-3 pixels => 0-3 bytes
+                     if (width_mmx)
+                     {
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $7, %%esi          \n\t"
+                           "subl $15, %%edi         \n\t"
+
+                        ".loop1_pass4:              \n\t"
+                           "movq (%%esi), %%mm0     \n\t" // 7 6 5 4 3 2 1 0
+                           "movq %%mm0, %%mm1       \n\t" // 7 6 5 4 3 2 1 0
+                           "punpcklbw %%mm0, %%mm0  \n\t" // 3 3 2 2 1 1 0 0
+                           "punpckhbw %%mm1, %%mm1  \n\t" // 7 7 6 6 5 5 4 4
+                           "movq %%mm1, 8(%%edi)    \n\t"
+                           "subl $8, %%esi          \n\t"
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "subl $16, %%edi         \n\t"
+                           "subl $8, %%ecx          \n\t"
+                           "jnz .loop1_pass4        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (none)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width_mmx)  // ecx
+
+#if 0  /* %mm0, %mm1 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0", "%mm1"               // clobber list
+#endif
+                        );
+                     }
+
+                     sptr -= width_mmx;
+                     dp -= width_mmx*2;
+                     for (i = width; i; i--)
+                     {
+                        int j;
+
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           *dp-- = *sptr;
+                        }
+                        --sptr;
+                     }
+                  }
+               } /* end of pixel_bytes == 1 */
+
+               //--------------------------------------------------------------
+               else if (pixel_bytes == 2)
+               {
+                  if (((pass == 0) || (pass == 1)) && width)
+                  {
+                     int width_mmx = ((width >> 1) << 1);
+                     width -= width_mmx;        // 0,1 pixels => 0,2 bytes
+                     if (width_mmx)
+                     {
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $2, %%esi          \n\t"
+                           "subl $30, %%edi         \n\t"
+
+                        ".loop2_pass0:              \n\t"
+                           "movd (%%esi), %%mm0     \n\t" // x x x x 3 2 1 0
+                           "punpcklwd %%mm0, %%mm0  \n\t" // 3 2 3 2 1 0 1 0
+                           "movq %%mm0, %%mm1       \n\t" // 3 2 3 2 1 0 1 0
+                           "punpckldq %%mm0, %%mm0  \n\t" // 1 0 1 0 1 0 1 0
+                           "punpckhdq %%mm1, %%mm1  \n\t" // 3 2 3 2 3 2 3 2
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "movq %%mm0, 8(%%edi)    \n\t"
+                           "movq %%mm1, 16(%%edi)   \n\t"
+                           "subl $4, %%esi          \n\t"
+                           "movq %%mm1, 24(%%edi)   \n\t"
+                           "subl $32, %%edi         \n\t"
+                           "subl $2, %%ecx          \n\t"
+                           "jnz .loop2_pass0        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (dummy)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width_mmx)  // ecx
+
+#if 0  /* %mm0, %mm1 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0", "%mm1"               // clobber list
+#endif
+                        );
+                     }
+
+                     sptr -= (width_mmx*2 - 2); // sign fixed
+                     dp -= (width_mmx*16 - 2);  // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 2;
+                        png_memcpy(v, sptr, 2);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 2;
+                           png_memcpy(dp, v, 2);
+                        }
+                     }
+                  }
+                  else if (((pass == 2) || (pass == 3)) && width)
+                  {
+                     int width_mmx = ((width >> 1) << 1) ;
+                     width -= width_mmx;        // 0,1 pixels => 0,2 bytes
+                     if (width_mmx)
+                     {
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $2, %%esi          \n\t"
+                           "subl $14, %%edi         \n\t"
+
+                        ".loop2_pass2:              \n\t"
+                           "movd (%%esi), %%mm0     \n\t" // x x x x 3 2 1 0
+                           "punpcklwd %%mm0, %%mm0  \n\t" // 3 2 3 2 1 0 1 0
+                           "movq %%mm0, %%mm1       \n\t" // 3 2 3 2 1 0 1 0
+                           "punpckldq %%mm0, %%mm0  \n\t" // 1 0 1 0 1 0 1 0
+                           "punpckhdq %%mm1, %%mm1  \n\t" // 3 2 3 2 3 2 3 2
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "subl $4, %%esi          \n\t"
+                           "movq %%mm1, 8(%%edi)    \n\t"
+                           "subl $16, %%edi         \n\t"
+                           "subl $2, %%ecx          \n\t"
+                           "jnz .loop2_pass2        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (dummy)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width_mmx)  // ecx
+
+#if 0  /* %mm0, %mm1 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0", "%mm1"               // clobber list
+#endif
+                        );
+                     }
+
+                     sptr -= (width_mmx*2 - 2); // sign fixed
+                     dp -= (width_mmx*8 - 2);   // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 2;
+                        png_memcpy(v, sptr, 2);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 2;
+                           png_memcpy(dp, v, 2);
+                        }
+                     }
+                  }
+                  else if (width)  // pass == 4 or 5
+                  {
+                     int width_mmx = ((width >> 1) << 1) ;
+                     width -= width_mmx;        // 0,1 pixels => 0,2 bytes
+                     if (width_mmx)
+                     {
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $2, %%esi          \n\t"
+                           "subl $6, %%edi          \n\t"
+
+                        ".loop2_pass4:              \n\t"
+                           "movd (%%esi), %%mm0     \n\t" // x x x x 3 2 1 0
+                           "punpcklwd %%mm0, %%mm0  \n\t" // 3 2 3 2 1 0 1 0
+                           "subl $4, %%esi          \n\t"
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "subl $8, %%edi          \n\t"
+                           "subl $2, %%ecx          \n\t"
+                           "jnz .loop2_pass4        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (dummy)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width_mmx)  // ecx
+
+#if 0  /* %mm0 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0"                       // clobber list
+#endif
+                        );
+                     }
+
+                     sptr -= (width_mmx*2 - 2); // sign fixed
+                     dp -= (width_mmx*4 - 2);   // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 2;
+                        png_memcpy(v, sptr, 2);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 2;
+                           png_memcpy(dp, v, 2);
+                        }
+                     }
+                  }
+               } /* end of pixel_bytes == 2 */
+
+               //--------------------------------------------------------------
+               else if (pixel_bytes == 4)
+               {
+                  if (((pass == 0) || (pass == 1)) && width)
+                  {
+                     int width_mmx = ((width >> 1) << 1);
+                     width -= width_mmx;        // 0,1 pixels => 0,4 bytes
+                     if (width_mmx)
+                     {
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $4, %%esi          \n\t"
+                           "subl $60, %%edi         \n\t"
+
+                        ".loop4_pass0:              \n\t"
+                           "movq (%%esi), %%mm0     \n\t" // 7 6 5 4 3 2 1 0
+                           "movq %%mm0, %%mm1       \n\t" // 7 6 5 4 3 2 1 0
+                           "punpckldq %%mm0, %%mm0  \n\t" // 3 2 1 0 3 2 1 0
+                           "punpckhdq %%mm1, %%mm1  \n\t" // 7 6 5 4 7 6 5 4
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "movq %%mm0, 8(%%edi)    \n\t"
+                           "movq %%mm0, 16(%%edi)   \n\t"
+                           "movq %%mm0, 24(%%edi)   \n\t"
+                           "movq %%mm1, 32(%%edi)   \n\t"
+                           "movq %%mm1, 40(%%edi)   \n\t"
+                           "movq %%mm1, 48(%%edi)   \n\t"
+                           "subl $8, %%esi          \n\t"
+                           "movq %%mm1, 56(%%edi)   \n\t"
+                           "subl $64, %%edi         \n\t"
+                           "subl $2, %%ecx          \n\t"
+                           "jnz .loop4_pass0        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (dummy)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width_mmx)  // ecx
+
+#if 0  /* %mm0, %mm1 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0", "%mm1"               // clobber list
+#endif
+                        );
+                     }
+
+                     sptr -= (width_mmx*4 - 4); // sign fixed
+                     dp -= (width_mmx*32 - 4);  // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 4;
+                        png_memcpy(v, sptr, 4);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 4;
+                           png_memcpy(dp, v, 4);
+                        }
+                     }
+                  }
+                  else if (((pass == 2) || (pass == 3)) && width)
+                  {
+                     int width_mmx = ((width >> 1) << 1);
+                     width -= width_mmx;        // 0,1 pixels => 0,4 bytes
+                     if (width_mmx)
+                     {
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $4, %%esi          \n\t"
+                           "subl $28, %%edi         \n\t"
+
+                        ".loop4_pass2:              \n\t"
+                           "movq (%%esi), %%mm0     \n\t" // 7 6 5 4 3 2 1 0
+                           "movq %%mm0, %%mm1       \n\t" // 7 6 5 4 3 2 1 0
+                           "punpckldq %%mm0, %%mm0  \n\t" // 3 2 1 0 3 2 1 0
+                           "punpckhdq %%mm1, %%mm1  \n\t" // 7 6 5 4 7 6 5 4
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "movq %%mm0, 8(%%edi)    \n\t"
+                           "movq %%mm1, 16(%%edi)   \n\t"
+                           "movq %%mm1, 24(%%edi)   \n\t"
+                           "subl $8, %%esi          \n\t"
+                           "subl $32, %%edi         \n\t"
+                           "subl $2, %%ecx          \n\t"
+                           "jnz .loop4_pass2        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (dummy)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width_mmx)  // ecx
+
+#if 0  /* %mm0, %mm1 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0", "%mm1"               // clobber list
+#endif
+                        );
+                     }
+
+                     sptr -= (width_mmx*4 - 4); // sign fixed
+                     dp -= (width_mmx*16 - 4);  // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 4;
+                        png_memcpy(v, sptr, 4);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 4;
+                           png_memcpy(dp, v, 4);
+                        }
+                     }
+                  }
+                  else if (width)  // pass == 4 or 5
+                  {
+                     int width_mmx = ((width >> 1) << 1) ;
+                     width -= width_mmx;        // 0,1 pixels => 0,4 bytes
+                     if (width_mmx)
+                     {
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $4, %%esi          \n\t"
+                           "subl $12, %%edi         \n\t"
+
+                        ".loop4_pass4:              \n\t"
+                           "movq (%%esi), %%mm0     \n\t" // 7 6 5 4 3 2 1 0
+                           "movq %%mm0, %%mm1       \n\t" // 7 6 5 4 3 2 1 0
+                           "punpckldq %%mm0, %%mm0  \n\t" // 3 2 1 0 3 2 1 0
+                           "punpckhdq %%mm1, %%mm1  \n\t" // 7 6 5 4 7 6 5 4
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "subl $8, %%esi          \n\t"
+                           "movq %%mm1, 8(%%edi)    \n\t"
+                           "subl $16, %%edi         \n\t"
+                           "subl $2, %%ecx          \n\t"
+                           "jnz .loop4_pass4        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (dummy)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width_mmx)  // ecx
+
+#if 0  /* %mm0, %mm1 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0", "%mm1"               // clobber list
+#endif
+                        );
+                     }
+
+                     sptr -= (width_mmx*4 - 4); // sign fixed
+                     dp -= (width_mmx*8 - 4);   // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 4;
+                        png_memcpy(v, sptr, 4);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 4;
+                           png_memcpy(dp, v, 4);
+                        }
+                     }
+                  }
+               } /* end of pixel_bytes == 4 */
+
+               //--------------------------------------------------------------
+               else if (pixel_bytes == 8)
+               {
+// GRR TEST:  should work, but needs testing (special 64-bit version of rpng2?)
+                  // GRR NOTE:  no need to combine passes here!
+                  if (((pass == 0) || (pass == 1)) && width)
+                  {
+                     int dummy_value_c;  // fix 'forbidden register spilled'
+                     int dummy_value_S;
+                     int dummy_value_D;
+
+                     // source is 8-byte RRGGBBAA
+                     // dest is 64-byte RRGGBBAA RRGGBBAA RRGGBBAA RRGGBBAA ...
+                     __asm__ __volatile__ (
+                        "subl $56, %%edi         \n\t" // start of last block
+
+                     ".loop8_pass0:              \n\t"
+                        "movq (%%esi), %%mm0     \n\t" // 7 6 5 4 3 2 1 0
+                        "movq %%mm0, (%%edi)     \n\t"
+                        "movq %%mm0, 8(%%edi)    \n\t"
+                        "movq %%mm0, 16(%%edi)   \n\t"
+                        "movq %%mm0, 24(%%edi)   \n\t"
+                        "movq %%mm0, 32(%%edi)   \n\t"
+                        "movq %%mm0, 40(%%edi)   \n\t"
+                        "movq %%mm0, 48(%%edi)   \n\t"
+                        "subl $8, %%esi          \n\t"
+                        "movq %%mm0, 56(%%edi)   \n\t"
+                        "subl $64, %%edi         \n\t"
+                        "decl %%ecx              \n\t"
+                        "jnz .loop8_pass0        \n\t"
+                        "EMMS                    \n\t" // DONE
+
+                        : "=c" (dummy_value_c),        // output regs (dummy)
+                          "=S" (dummy_value_S),
+                          "=D" (dummy_value_D)
+
+                        : "1" (sptr),      // esi      // input regs
+                          "2" (dp),        // edi
+                          "0" (width)      // ecx
+
+#if 0  /* %mm0 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                        : "%mm0"                       // clobber list
+#endif
+                     );
+                  }
+                  else if (((pass == 2) || (pass == 3)) && width)
+                  {
+                     // source is 8-byte RRGGBBAA
+                     // dest is 32-byte RRGGBBAA RRGGBBAA RRGGBBAA RRGGBBAA
+                     // (recall that expansion is _in place_:  sptr and dp
+                     //  both point at locations within same row buffer)
+                     {
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $24, %%edi         \n\t" // start of last block
+
+                        ".loop8_pass2:              \n\t"
+                           "movq (%%esi), %%mm0     \n\t" // 7 6 5 4 3 2 1 0
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "movq %%mm0, 8(%%edi)    \n\t"
+                           "movq %%mm0, 16(%%edi)   \n\t"
+                           "subl $8, %%esi          \n\t"
+                           "movq %%mm0, 24(%%edi)   \n\t"
+                           "subl $32, %%edi         \n\t"
+                           "decl %%ecx              \n\t"
+                           "jnz .loop8_pass2        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (dummy)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width)      // ecx
+
+#if 0  /* %mm0 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0"                       // clobber list
+#endif
+                        );
+                     }
+                  }
+                  else if (width)  // pass == 4 or 5
+                  {
+                     // source is 8-byte RRGGBBAA
+                     // dest is 16-byte RRGGBBAA RRGGBBAA
+                     {
+                        int dummy_value_c;  // fix 'forbidden register spilled'
+                        int dummy_value_S;
+                        int dummy_value_D;
+
+                        __asm__ __volatile__ (
+                           "subl $8, %%edi          \n\t" // start of last block
+
+                        ".loop8_pass4:              \n\t"
+                           "movq (%%esi), %%mm0     \n\t" // 7 6 5 4 3 2 1 0
+                           "movq %%mm0, (%%edi)     \n\t"
+                           "subl $8, %%esi          \n\t"
+                           "movq %%mm0, 8(%%edi)    \n\t"
+                           "subl $16, %%edi         \n\t"
+                           "decl %%ecx              \n\t"
+                           "jnz .loop8_pass4        \n\t"
+                           "EMMS                    \n\t" // DONE
+
+                           : "=c" (dummy_value_c),        // output regs (dummy)
+                             "=S" (dummy_value_S),
+                             "=D" (dummy_value_D)
+
+                           : "1" (sptr),      // esi      // input regs
+                             "2" (dp),        // edi
+                             "0" (width)      // ecx
+
+#if 0  /* %mm0 not supported by gcc 2.7.2.3 or egcs 1.1 */
+                           : "%mm0"                       // clobber list
+#endif
+                        );
+                     }
+                  }
+
+               } /* end of pixel_bytes == 8 */
+
+               //--------------------------------------------------------------
+               else if (pixel_bytes == 6)
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, 6);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, 6);
+                        dp -= 6;
+                     }
+                     sptr -= 6;
+                  }
+               } /* end of pixel_bytes == 6 */
+
+               //--------------------------------------------------------------
+               else
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, pixel_bytes);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, pixel_bytes);
+                        dp -= pixel_bytes;
+                     }
+                     sptr-= pixel_bytes;
+                  }
+               }
+            } // end of _mmx_supported ========================================
+
+            else /* MMX not supported:  use modified C code - takes advantage
+                  *   of inlining of png_memcpy for a constant */
+                 /* GRR 19991007:  does it?  or should pixel_bytes in each
+                  *   block be replaced with immediate value (e.g., 1)? */
+                 /* GRR 19991017:  replaced with constants in each case */
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+            {
+               if (pixel_bytes == 1)
+               {
+                  for (i = width; i; i--)
+                  {
+                     int j;
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        *dp-- = *sptr;
+                     }
+                     --sptr;
+                  }
+               }
+               else if (pixel_bytes == 3)
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, 3);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, 3);
+                        dp -= 3;
+                     }
+                     sptr -= 3;
+                  }
+               }
+               else if (pixel_bytes == 2)
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, 2);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, 2);
+                        dp -= 2;
+                     }
+                     sptr -= 2;
+                  }
+               }
+               else if (pixel_bytes == 4)
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, 4);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+#ifdef PNG_DEBUG
+                        if (dp < row || dp+3 > row+png_ptr->row_buf_size)
+                        {
+                           printf("dp out of bounds: row=%d, dp=%d, rp=%d\n",
+                             row, dp, row+png_ptr->row_buf_size);
+                           printf("row_buf=%d\n",png_ptr->row_buf_size);
+                        }
+#endif
+                        png_memcpy(dp, v, 4);
+                        dp -= 4;
+                     }
+                     sptr -= 4;
+                  }
+               }
+               else if (pixel_bytes == 6)
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, 6);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, 6);
+                        dp -= 6;
+                     }
+                     sptr -= 6;
+                  }
+               }
+               else if (pixel_bytes == 8)
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, 8);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, 8);
+                        dp -= 8;
+                     }
+                     sptr -= 8;
+                  }
+               }
+               else     /* GRR:  should never be reached */
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, pixel_bytes);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, pixel_bytes);
+                        dp -= pixel_bytes;
+                     }
+                     sptr -= pixel_bytes;
+                  }
+               }
+
+            } /* end if (MMX not supported) */
+            break;
+         }
+      } /* end switch (row_info->pixel_depth) */
+
+      row_info->width = final_width;
+
+      row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,final_width);
+   }
+
+} /* end png_do_read_interlace() */
+
+#endif /* PNG_HAVE_ASSEMBLER_READ_INTERLACE */
+#endif /* PNG_READ_INTERLACING_SUPPORTED */
+
+
+
+#if defined(PNG_HAVE_ASSEMBLER_READ_FILTER_ROW)
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+
+// These variables are utilized in the functions below.  They are declared
+// globally here to ensure alignment on 8-byte boundaries.
+
+union uAll {
+   long long use;
+   double  align;
+} _LBCarryMask = {0x0101010101010101LL},
+  _HBClearMask = {0x7f7f7f7f7f7f7f7fLL},
+  _ActiveMask, _ActiveMask2, _ActiveMaskEnd, _ShiftBpp, _ShiftRem;
+
+#ifdef PNG_THREAD_UNSAFE_OK
+//===========================================================================//
+//                                                                           //
+//           P N G _ R E A D _ F I L T E R _ R O W _ M M X _ A V G           //
+//                                                                           //
+//===========================================================================//
+
+// Optimized code for PNG Average filter decoder
+
+static void /* PRIVATE */
+png_read_filter_row_mmx_avg(png_row_infop row_info, png_bytep row,
+                            png_bytep prev_row)
+{
+   int bpp;
+   int dummy_value_c;   // fix 'forbidden register 2 (cx) was spilled' error
+   int dummy_value_S;
+   int dummy_value_D;
+
+   bpp = (row_info->pixel_depth + 7) >> 3;  // get # bytes per pixel
+   _FullLength  = row_info->rowbytes;       // # of bytes to filter
+
+   __asm__ __volatile__ (
+      // initialize address pointers and offset
+#ifdef __PIC__
+      "pushl %%ebx                 \n\t" // save index to Global Offset Table
+#endif
+//pre "movl row, %%edi             \n\t" // edi:  Avg(x)
+      "xorl %%ebx, %%ebx           \n\t" // ebx:  x
+      "movl %%edi, %%edx           \n\t"
+//pre "movl prev_row, %%esi        \n\t" // esi:  Prior(x)
+//pre "subl bpp, %%edx             \n\t" // (bpp is preloaded into ecx)
+      "subl %%ecx, %%edx           \n\t" // edx:  Raw(x-bpp)
+
+      "xorl %%eax,%%eax            \n\t"
+
+      // Compute the Raw value for the first bpp bytes
+      //    Raw(x) = Avg(x) + (Prior(x)/2)
+   "avg_rlp:                       \n\t"
+      "movb (%%esi,%%ebx,),%%al    \n\t" // load al with Prior(x)
+      "incl %%ebx                  \n\t"
+      "shrb %%al                   \n\t" // divide by 2
+      "addb -1(%%edi,%%ebx,),%%al  \n\t" // add Avg(x); -1 to offset inc ebx
+//pre "cmpl bpp, %%ebx             \n\t" // (bpp is preloaded into ecx)
+      "cmpl %%ecx, %%ebx           \n\t"
+      "movb %%al,-1(%%edi,%%ebx,)  \n\t" // write Raw(x); -1 to offset inc ebx
+      "jb avg_rlp                  \n\t" // mov does not affect flags
+
+      // get # of bytes to alignment
+      "movl %%edi, _dif            \n\t" // take start of row
+      "addl %%ebx, _dif            \n\t" // add bpp
+      "addl $0xf, _dif             \n\t" // add 7+8 to incr past alignment bdry
+      "andl $0xfffffff8, _dif      \n\t" // mask to alignment boundary
+      "subl %%edi, _dif            \n\t" // subtract from start => value ebx at
+      "jz avg_go                   \n\t" //  alignment
+
+      // fix alignment
+      // Compute the Raw value for the bytes up to the alignment boundary
+      //    Raw(x) = Avg(x) + ((Raw(x-bpp) + Prior(x))/2)
+      "xorl %%ecx, %%ecx           \n\t"
+
+   "avg_lp1:                       \n\t"
+      "xorl %%eax, %%eax           \n\t"
+      "movb (%%esi,%%ebx,), %%cl   \n\t" // load cl with Prior(x)
+      "movb (%%edx,%%ebx,), %%al   \n\t" // load al with Raw(x-bpp)
+      "addw %%cx, %%ax             \n\t"
+      "incl %%ebx                  \n\t"
+      "shrw %%ax                   \n\t" // divide by 2
+      "addb -1(%%edi,%%ebx,), %%al \n\t" // add Avg(x); -1 to offset inc ebx
+      "cmpl _dif, %%ebx            \n\t" // check if at alignment boundary
+      "movb %%al, -1(%%edi,%%ebx,) \n\t" // write Raw(x); -1 to offset inc ebx
+      "jb avg_lp1                  \n\t" // repeat until at alignment boundary
+
+   "avg_go:                        \n\t"
+      "movl _FullLength, %%eax     \n\t"
+      "movl %%eax, %%ecx           \n\t"
+      "subl %%ebx, %%eax           \n\t" // subtract alignment fix
+      "andl $0x00000007, %%eax     \n\t" // calc bytes over mult of 8
+      "subl %%eax, %%ecx           \n\t" // drop over bytes from original length
+      "movl %%ecx, _MMXLength      \n\t"
+#ifdef __PIC__
+      "popl %%ebx                  \n\t" // restore index to Global Offset Table
+#endif
+
+      : "=c" (dummy_value_c),            // output regs (dummy)
+        "=S" (dummy_value_S),
+        "=D" (dummy_value_D)
+
+      : "0" (bpp),       // ecx          // input regs
+        "1" (prev_row),  // esi
+        "2" (row)        // edi
+
+      : "%eax", "%edx"                   // clobber list
+#ifndef __PIC__
+      , "%ebx"
+#endif
+      // GRR: INCLUDE "memory" as clobbered? (_dif, _MMXLength)
+      // (seems to work fine without...)
+   );
+
+   // now do the math for the rest of the row
+   switch (bpp)
+   {
+      case 3:
+      {
+         _ActiveMask.use  = 0x0000000000ffffffLL;
+         _ShiftBpp.use = 24;    // == 3 * 8
+         _ShiftRem.use = 40;    // == 64 - 24
+
+         __asm__ __volatile__ (
+            // re-init address pointers and offset
+            "movq _ActiveMask, %%mm7      \n\t"
+            "movl _dif, %%ecx             \n\t" // ecx:  x = offset to
+            "movq _LBCarryMask, %%mm5     \n\t" //  alignment boundary
+// preload  "movl row, %%edi              \n\t" // edi:  Avg(x)
+            "movq _HBClearMask, %%mm4     \n\t"
+// preload  "movl prev_row, %%esi         \n\t" // esi:  Prior(x)
+
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%ecx,), %%mm2 \n\t" // load previous aligned 8 bytes
+                                                // (correct pos. in loop below)
+         "avg_3lp:                        \n\t"
+            "movq (%%edi,%%ecx,), %%mm0   \n\t" // load mm0 with Avg(x)
+            "movq %%mm5, %%mm3            \n\t"
+            "psrlq _ShiftRem, %%mm2       \n\t" // correct position Raw(x-bpp)
+                                                // data
+            "movq (%%esi,%%ecx,), %%mm1   \n\t" // load mm1 with Prior(x)
+            "movq %%mm7, %%mm6            \n\t"
+            "pand %%mm1, %%mm3            \n\t" // get lsb for each prev_row byte
+            "psrlq $1, %%mm1              \n\t" // divide prev_row bytes by 2
+            "pand  %%mm4, %%mm1           \n\t" // clear invalid bit 7 of each
+                                                // byte
+            "paddb %%mm1, %%mm0           \n\t" // add (Prev_row/2) to Avg for
+                                                // each byte
+            // add 1st active group (Raw(x-bpp)/2) to average with LBCarry
+            "movq %%mm3, %%mm1            \n\t" // now use mm1 for getting
+                                                // LBCarrys
+            "pand %%mm2, %%mm1            \n\t" // get LBCarrys for each byte
+                                                // where both
+                               // lsb's were == 1 (only valid for active group)
+            "psrlq $1, %%mm2              \n\t" // divide raw bytes by 2
+            "pand  %%mm4, %%mm2           \n\t" // clear invalid bit 7 of each
+                                                // byte
+            "paddb %%mm1, %%mm2           \n\t" // add LBCarrys to (Raw(x-bpp)/2)
+                                                // for each byte
+            "pand %%mm6, %%mm2            \n\t" // leave only Active Group 1
+                                                // bytes to add to Avg
+            "paddb %%mm2, %%mm0           \n\t" // add (Raw/2) + LBCarrys to
+                                                // Avg for each Active
+                               //  byte
+            // add 2nd active group (Raw(x-bpp)/2) to average with _LBCarry
+            "psllq _ShiftBpp, %%mm6       \n\t" // shift the mm6 mask to cover
+                                                // bytes 3-5
+            "movq %%mm0, %%mm2            \n\t" // mov updated Raws to mm2
+            "psllq _ShiftBpp, %%mm2       \n\t" // shift data to pos. correctly
+            "movq %%mm3, %%mm1            \n\t" // now use mm1 for getting
+                                                // LBCarrys
+            "pand %%mm2, %%mm1            \n\t" // get LBCarrys for each byte
+                                                // where both
+                               // lsb's were == 1 (only valid for active group)
+            "psrlq $1, %%mm2              \n\t" // divide raw bytes by 2
+            "pand  %%mm4, %%mm2           \n\t" // clear invalid bit 7 of each
+                                                // byte
+            "paddb %%mm1, %%mm2           \n\t" // add LBCarrys to (Raw(x-bpp)/2)
+                                                // for each byte
+            "pand %%mm6, %%mm2            \n\t" // leave only Active Group 2
+                                                // bytes to add to Avg
+            "paddb %%mm2, %%mm0           \n\t" // add (Raw/2) + LBCarrys to
+                                                // Avg for each Active
+                               //  byte
+
+            // add 3rd active group (Raw(x-bpp)/2) to average with _LBCarry
+            "psllq _ShiftBpp, %%mm6       \n\t" // shift mm6 mask to cover last
+                                                // two
+                                 // bytes
+            "movq %%mm0, %%mm2            \n\t" // mov updated Raws to mm2
+            "psllq _ShiftBpp, %%mm2       \n\t" // shift data to pos. correctly
+                              // Data only needs to be shifted once here to
+                              // get the correct x-bpp offset.
+            "movq %%mm3, %%mm1            \n\t" // now use mm1 for getting
+                                                // LBCarrys
+            "pand %%mm2, %%mm1            \n\t" // get LBCarrys for each byte
+                                                // where both
+                              // lsb's were == 1 (only valid for active group)
+            "psrlq $1, %%mm2              \n\t" // divide raw bytes by 2
+            "pand  %%mm4, %%mm2           \n\t" // clear invalid bit 7 of each
+                                                // byte
+            "paddb %%mm1, %%mm2           \n\t" // add LBCarrys to (Raw(x-bpp)/2)
+                                                // for each byte
+            "pand %%mm6, %%mm2            \n\t" // leave only Active Group 2
+                                                // bytes to add to Avg
+            "addl $8, %%ecx               \n\t"
+            "paddb %%mm2, %%mm0           \n\t" // add (Raw/2) + LBCarrys to
+                                                // Avg for each Active
+                                                // byte
+            // now ready to write back to memory
+            "movq %%mm0, -8(%%edi,%%ecx,) \n\t"
+            // move updated Raw(x) to use as Raw(x-bpp) for next loop
+            "cmpl _MMXLength, %%ecx       \n\t"
+            "movq %%mm0, %%mm2            \n\t" // mov updated Raw(x) to mm2
+            "jb avg_3lp                   \n\t"
+
+            : "=S" (dummy_value_S),             // output regs (dummy)
+              "=D" (dummy_value_D)
+
+            : "0" (prev_row),  // esi           // input regs
+              "1" (row)        // edi
+
+            : "%ecx"                            // clobber list
+#if 0  /* %mm0, ..., %mm7 not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1", "%mm2", "%mm3"
+            , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+         );
+      }
+      break;  // end 3 bpp
+
+      case 6:
+      case 4:
+      //case 7:   // who wrote this?  PNG doesn't support 5 or 7 bytes/pixel
+      //case 5:   // GRR BOGUS
+      {
+         _ActiveMask.use  = 0xffffffffffffffffLL; // use shift below to clear
+                                                  // appropriate inactive bytes
+         _ShiftBpp.use = bpp << 3;
+         _ShiftRem.use = 64 - _ShiftBpp.use;
+
+         __asm__ __volatile__ (
+            "movq _HBClearMask, %%mm4    \n\t"
+
+            // re-init address pointers and offset
+            "movl _dif, %%ecx            \n\t" // ecx:  x = offset to
+                                               // alignment boundary
+
+            // load _ActiveMask and clear all bytes except for 1st active group
+            "movq _ActiveMask, %%mm7     \n\t"
+// preload  "movl row, %%edi             \n\t" // edi:  Avg(x)
+            "psrlq _ShiftRem, %%mm7      \n\t"
+// preload  "movl prev_row, %%esi        \n\t" // esi:  Prior(x)
+            "movq %%mm7, %%mm6           \n\t"
+            "movq _LBCarryMask, %%mm5    \n\t"
+            "psllq _ShiftBpp, %%mm6      \n\t" // create mask for 2nd active
+                                               // group
+
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%ecx,), %%mm2 \n\t" // load previous aligned 8 bytes
+                                          // (we correct pos. in loop below)
+         "avg_4lp:                       \n\t"
+            "movq (%%edi,%%ecx,), %%mm0  \n\t"
+            "psrlq _ShiftRem, %%mm2      \n\t" // shift data to pos. correctly
+            "movq (%%esi,%%ecx,), %%mm1  \n\t"
+            // add (Prev_row/2) to average
+            "movq %%mm5, %%mm3           \n\t"
+            "pand %%mm1, %%mm3           \n\t" // get lsb for each prev_row byte
+            "psrlq $1, %%mm1             \n\t" // divide prev_row bytes by 2
+            "pand  %%mm4, %%mm1          \n\t" // clear invalid bit 7 of each
+                                               // byte
+            "paddb %%mm1, %%mm0          \n\t" // add (Prev_row/2) to Avg for
+                                               // each byte
+            // add 1st active group (Raw(x-bpp)/2) to average with _LBCarry
+            "movq %%mm3, %%mm1           \n\t" // now use mm1 for getting
+                                               // LBCarrys
+            "pand %%mm2, %%mm1           \n\t" // get LBCarrys for each byte
+                                               // where both
+                              // lsb's were == 1 (only valid for active group)
+            "psrlq $1, %%mm2             \n\t" // divide raw bytes by 2
+            "pand  %%mm4, %%mm2          \n\t" // clear invalid bit 7 of each
+                                               // byte
+            "paddb %%mm1, %%mm2          \n\t" // add LBCarrys to (Raw(x-bpp)/2)
+                                               // for each byte
+            "pand %%mm7, %%mm2           \n\t" // leave only Active Group 1
+                                               // bytes to add to Avg
+            "paddb %%mm2, %%mm0          \n\t" // add (Raw/2) + LBCarrys to Avg
+                                               // for each Active
+                              // byte
+            // add 2nd active group (Raw(x-bpp)/2) to average with _LBCarry
+            "movq %%mm0, %%mm2           \n\t" // mov updated Raws to mm2
+            "psllq _ShiftBpp, %%mm2      \n\t" // shift data to pos. correctly
+            "addl $8, %%ecx              \n\t"
+            "movq %%mm3, %%mm1           \n\t" // now use mm1 for getting
+                                               // LBCarrys
+            "pand %%mm2, %%mm1           \n\t" // get LBCarrys for each byte
+                                               // where both
+                              // lsb's were == 1 (only valid for active group)
+            "psrlq $1, %%mm2             \n\t" // divide raw bytes by 2
+            "pand  %%mm4, %%mm2          \n\t" // clear invalid bit 7 of each
+                                               // byte
+            "paddb %%mm1, %%mm2          \n\t" // add LBCarrys to (Raw(x-bpp)/2)
+                                               // for each byte
+            "pand %%mm6, %%mm2           \n\t" // leave only Active Group 2
+                                               // bytes to add to Avg
+            "paddb %%mm2, %%mm0          \n\t" // add (Raw/2) + LBCarrys to
+                                               // Avg for each Active
+                              // byte
+            "cmpl _MMXLength, %%ecx      \n\t"
+            // now ready to write back to memory
+            "movq %%mm0, -8(%%edi,%%ecx,) \n\t"
+            // prep Raw(x-bpp) for next loop
+            "movq %%mm0, %%mm2           \n\t" // mov updated Raws to mm2
+            "jb avg_4lp                  \n\t"
+
+            : "=S" (dummy_value_S),            // output regs (dummy)
+              "=D" (dummy_value_D)
+
+            : "0" (prev_row),  // esi          // input regs
+              "1" (row)        // edi
+
+            : "%ecx"                           // clobber list
+#if 0  /* %mm0, ..., %mm7 not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1", "%mm2", "%mm3"
+            , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+         );
+      }
+      break;  // end 4,6 bpp
+
+      case 2:
+      {
+         _ActiveMask.use  = 0x000000000000ffffLL;
+         _ShiftBpp.use = 16;   // == 2 * 8
+         _ShiftRem.use = 48;   // == 64 - 16
+
+         __asm__ __volatile__ (
+            // load _ActiveMask
+            "movq _ActiveMask, %%mm7     \n\t"
+            // re-init address pointers and offset
+            "movl _dif, %%ecx            \n\t" // ecx:  x = offset to alignment
+                                               // boundary
+            "movq _LBCarryMask, %%mm5    \n\t"
+// preload  "movl row, %%edi             \n\t" // edi:  Avg(x)
+            "movq _HBClearMask, %%mm4    \n\t"
+// preload  "movl prev_row, %%esi        \n\t" // esi:  Prior(x)
+
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%ecx,), %%mm2 \n\t" // load previous aligned 8 bytes
+                              // (we correct pos. in loop below)
+         "avg_2lp:                       \n\t"
+            "movq (%%edi,%%ecx,), %%mm0  \n\t"
+            "psrlq _ShiftRem, %%mm2      \n\t" // shift data to pos. correctly
+            "movq (%%esi,%%ecx,), %%mm1  \n\t" //  (GRR BUGFIX:  was psllq)
+            // add (Prev_row/2) to average
+            "movq %%mm5, %%mm3           \n\t"
+            "pand %%mm1, %%mm3           \n\t" // get lsb for each prev_row byte
+            "psrlq $1, %%mm1             \n\t" // divide prev_row bytes by 2
+            "pand  %%mm4, %%mm1          \n\t" // clear invalid bit 7 of each
+                                               // byte
+            "movq %%mm7, %%mm6           \n\t"
+            "paddb %%mm1, %%mm0          \n\t" // add (Prev_row/2) to Avg for
+                                               // each byte
+
+            // add 1st active group (Raw(x-bpp)/2) to average with _LBCarry
+            "movq %%mm3, %%mm1           \n\t" // now use mm1 for getting
+                                               // LBCarrys
+            "pand %%mm2, %%mm1           \n\t" // get LBCarrys for each byte
+                                               // where both
+                                               // lsb's were == 1 (only valid
+                                               // for active group)
+            "psrlq $1, %%mm2             \n\t" // divide raw bytes by 2
+            "pand  %%mm4, %%mm2          \n\t" // clear invalid bit 7 of each
+                                               // byte
+            "paddb %%mm1, %%mm2          \n\t" // add LBCarrys to (Raw(x-bpp)/2)
+                                               // for each byte
+            "pand %%mm6, %%mm2           \n\t" // leave only Active Group 1
+                                               // bytes to add to Avg
+            "paddb %%mm2, %%mm0          \n\t" // add (Raw/2) + LBCarrys to Avg
+                                               // for each Active byte
+
+            // add 2nd active group (Raw(x-bpp)/2) to average with _LBCarry
+            "psllq _ShiftBpp, %%mm6      \n\t" // shift the mm6 mask to cover
+                                               // bytes 2 & 3
+            "movq %%mm0, %%mm2           \n\t" // mov updated Raws to mm2
+            "psllq _ShiftBpp, %%mm2      \n\t" // shift data to pos. correctly
+            "movq %%mm3, %%mm1           \n\t" // now use mm1 for getting
+                                               // LBCarrys
+            "pand %%mm2, %%mm1           \n\t" // get LBCarrys for each byte
+                                               // where both
+                                               // lsb's were == 1 (only valid
+                                               // for active group)
+            "psrlq $1, %%mm2             \n\t" // divide raw bytes by 2
+            "pand  %%mm4, %%mm2          \n\t" // clear invalid bit 7 of each
+                                               // byte
+            "paddb %%mm1, %%mm2          \n\t" // add LBCarrys to (Raw(x-bpp)/2)
+                                               // for each byte
+            "pand %%mm6, %%mm2           \n\t" // leave only Active Group 2
+                                               // bytes to add to Avg
+            "paddb %%mm2, %%mm0          \n\t" // add (Raw/2) + LBCarrys to
+                                               // Avg for each Active byte
+
+            // add 3rd active group (Raw(x-bpp)/2) to average with _LBCarry
+            "psllq _ShiftBpp, %%mm6      \n\t" // shift the mm6 mask to cover
+                                               // bytes 4 & 5
+            "movq %%mm0, %%mm2           \n\t" // mov updated Raws to mm2
+            "psllq _ShiftBpp, %%mm2      \n\t" // shift data to pos. correctly
+            "movq %%mm3, %%mm1           \n\t" // now use mm1 for getting
+                                               // LBCarrys
+            "pand %%mm2, %%mm1           \n\t" // get LBCarrys for each byte
+                                               // where both lsb's were == 1
+                                               // (only valid for active group)
+            "psrlq $1, %%mm2             \n\t" // divide raw bytes by 2
+            "pand  %%mm4, %%mm2          \n\t" // clear invalid bit 7 of each
+                                               // byte
+            "paddb %%mm1, %%mm2          \n\t" // add LBCarrys to (Raw(x-bpp)/2)
+                                               // for each byte
+            "pand %%mm6, %%mm2           \n\t" // leave only Active Group 2
+                                               // bytes to add to Avg
+            "paddb %%mm2, %%mm0          \n\t" // add (Raw/2) + LBCarrys to
+                                               // Avg for each Active byte
+
+            // add 4th active group (Raw(x-bpp)/2) to average with _LBCarry
+            "psllq _ShiftBpp, %%mm6      \n\t" // shift the mm6 mask to cover
+                                               // bytes 6 & 7
+            "movq %%mm0, %%mm2           \n\t" // mov updated Raws to mm2
+            "psllq _ShiftBpp, %%mm2      \n\t" // shift data to pos. correctly
+            "addl $8, %%ecx              \n\t"
+            "movq %%mm3, %%mm1           \n\t" // now use mm1 for getting
+                                               // LBCarrys
+            "pand %%mm2, %%mm1           \n\t" // get LBCarrys for each byte
+                                               // where both
+                                               // lsb's were == 1 (only valid
+                                               // for active group)
+            "psrlq $1, %%mm2             \n\t" // divide raw bytes by 2
+            "pand  %%mm4, %%mm2          \n\t" // clear invalid bit 7 of each
+                                               // byte
+            "paddb %%mm1, %%mm2          \n\t" // add LBCarrys to (Raw(x-bpp)/2)
+                                               // for each byte
+            "pand %%mm6, %%mm2           \n\t" // leave only Active Group 2
+                                               // bytes to add to Avg
+            "paddb %%mm2, %%mm0          \n\t" // add (Raw/2) + LBCarrys to
+                                               // Avg for each Active byte
+
+            "cmpl _MMXLength, %%ecx      \n\t"
+            // now ready to write back to memory
+            "movq %%mm0, -8(%%edi,%%ecx,) \n\t"
+            // prep Raw(x-bpp) for next loop
+            "movq %%mm0, %%mm2           \n\t" // mov updated Raws to mm2
+            "jb avg_2lp                  \n\t"
+
+            : "=S" (dummy_value_S),            // output regs (dummy)
+              "=D" (dummy_value_D)
+
+            : "0" (prev_row),  // esi          // input regs
+              "1" (row)        // edi
+
+            : "%ecx"                           // clobber list
+#if 0  /* %mm0, ..., %mm7 not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1", "%mm2", "%mm3"
+            , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+         );
+      }
+      break;  // end 2 bpp
+
+      case 1:
+      {
+         __asm__ __volatile__ (
+            // re-init address pointers and offset
+#ifdef __PIC__
+            "pushl %%ebx                 \n\t" // save Global Offset Table index
+#endif
+            "movl _dif, %%ebx            \n\t" // ebx:  x = offset to alignment
+                                               // boundary
+// preload  "movl row, %%edi             \n\t" // edi:  Avg(x)
+            "cmpl _FullLength, %%ebx     \n\t" // test if offset at end of array
+            "jnb avg_1end                \n\t"
+            // do Paeth decode for remaining bytes
+// preload  "movl prev_row, %%esi        \n\t" // esi:  Prior(x)
+            "movl %%edi, %%edx           \n\t"
+// preload  "subl bpp, %%edx             \n\t" // (bpp is preloaded into ecx)
+            "subl %%ecx, %%edx           \n\t" // edx:  Raw(x-bpp)
+            "xorl %%ecx, %%ecx           \n\t" // zero ecx before using cl & cx
+                                               //  in loop below
+         "avg_1lp:                       \n\t"
+            // Raw(x) = Avg(x) + ((Raw(x-bpp) + Prior(x))/2)
+            "xorl %%eax, %%eax           \n\t"
+            "movb (%%esi,%%ebx,), %%cl   \n\t" // load cl with Prior(x)
+            "movb (%%edx,%%ebx,), %%al   \n\t" // load al with Raw(x-bpp)
+            "addw %%cx, %%ax             \n\t"
+            "incl %%ebx                  \n\t"
+            "shrw %%ax                   \n\t" // divide by 2
+            "addb -1(%%edi,%%ebx,), %%al \n\t" // add Avg(x); -1 to offset
+                                               // inc ebx
+            "cmpl _FullLength, %%ebx     \n\t" // check if at end of array
+            "movb %%al, -1(%%edi,%%ebx,) \n\t" // write back Raw(x);
+                         // mov does not affect flags; -1 to offset inc ebx
+            "jb avg_1lp                  \n\t"
+
+         "avg_1end:                      \n\t"
+#ifdef __PIC__
+            "popl %%ebx                  \n\t" // Global Offset Table index
+#endif
+
+            : "=c" (dummy_value_c),            // output regs (dummy)
+              "=S" (dummy_value_S),
+              "=D" (dummy_value_D)
+
+            : "0" (bpp),       // ecx          // input regs
+              "1" (prev_row),  // esi
+              "2" (row)        // edi
+
+            : "%eax", "%edx"                   // clobber list
+#ifndef __PIC__
+            , "%ebx"
+#endif
+         );
+      }
+      return;  // end 1 bpp
+
+      case 8:
+      {
+         __asm__ __volatile__ (
+            // re-init address pointers and offset
+            "movl _dif, %%ecx            \n\t" // ecx:  x == offset to alignment
+            "movq _LBCarryMask, %%mm5    \n\t" //            boundary
+// preload  "movl row, %%edi             \n\t" // edi:  Avg(x)
+            "movq _HBClearMask, %%mm4    \n\t"
+// preload  "movl prev_row, %%esi        \n\t" // esi:  Prior(x)
+
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%ecx,), %%mm2 \n\t" // load previous aligned 8 bytes
+                                      // (NO NEED to correct pos. in loop below)
+
+         "avg_8lp:                       \n\t"
+            "movq (%%edi,%%ecx,), %%mm0  \n\t"
+            "movq %%mm5, %%mm3           \n\t"
+            "movq (%%esi,%%ecx,), %%mm1  \n\t"
+            "addl $8, %%ecx              \n\t"
+            "pand %%mm1, %%mm3           \n\t" // get lsb for each prev_row byte
+            "psrlq $1, %%mm1             \n\t" // divide prev_row bytes by 2
+            "pand %%mm2, %%mm3           \n\t" // get LBCarrys for each byte
+                                               //  where both lsb's were == 1
+            "psrlq $1, %%mm2             \n\t" // divide raw bytes by 2
+            "pand  %%mm4, %%mm1          \n\t" // clear invalid bit 7, each byte
+            "paddb %%mm3, %%mm0          \n\t" // add LBCarrys to Avg, each byte
+            "pand  %%mm4, %%mm2          \n\t" // clear invalid bit 7, each byte
+            "paddb %%mm1, %%mm0          \n\t" // add (Prev_row/2) to Avg, each
+            "paddb %%mm2, %%mm0          \n\t" // add (Raw/2) to Avg for each
+            "cmpl _MMXLength, %%ecx      \n\t"
+            "movq %%mm0, -8(%%edi,%%ecx,) \n\t"
+            "movq %%mm0, %%mm2           \n\t" // reuse as Raw(x-bpp)
+            "jb avg_8lp                  \n\t"
+
+            : "=S" (dummy_value_S),            // output regs (dummy)
+              "=D" (dummy_value_D)
+
+            : "0" (prev_row),  // esi          // input regs
+              "1" (row)        // edi
+
+            : "%ecx"                           // clobber list
+#if 0  /* %mm0, ..., %mm5 not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1", "%mm2"
+            , "%mm3", "%mm4", "%mm5"
+#endif
+         );
+      }
+      break;  // end 8 bpp
+
+      default:                  // bpp greater than 8 (!= 1,2,3,4,[5],6,[7],8)
+      {
+
+#ifdef PNG_DEBUG
+         // GRR:  PRINT ERROR HERE:  SHOULD NEVER BE REACHED
+        png_debug(1,
+        "Internal logic error in pnggccrd (png_read_filter_row_mmx_avg())\n");
+#endif
+
+#if 0
+        __asm__ __volatile__ (
+            "movq _LBCarryMask, %%mm5    \n\t"
+            // re-init address pointers and offset
+            "movl _dif, %%ebx            \n\t" // ebx:  x = offset to
+                                               // alignment boundary
+            "movl row, %%edi             \n\t" // edi:  Avg(x)
+            "movq _HBClearMask, %%mm4    \n\t"
+            "movl %%edi, %%edx           \n\t"
+            "movl prev_row, %%esi        \n\t" // esi:  Prior(x)
+            "subl bpp, %%edx             \n\t" // edx:  Raw(x-bpp)
+         "avg_Alp:                       \n\t"
+            "movq (%%edi,%%ebx,), %%mm0  \n\t"
+            "movq %%mm5, %%mm3           \n\t"
+            "movq (%%esi,%%ebx,), %%mm1  \n\t"
+            "pand %%mm1, %%mm3           \n\t" // get lsb for each prev_row byte
+            "movq (%%edx,%%ebx,), %%mm2  \n\t"
+            "psrlq $1, %%mm1             \n\t" // divide prev_row bytes by 2
+            "pand %%mm2, %%mm3           \n\t" // get LBCarrys for each byte
+                                               // where both lsb's were == 1
+            "psrlq $1, %%mm2             \n\t" // divide raw bytes by 2
+            "pand  %%mm4, %%mm1          \n\t" // clear invalid bit 7 of each
+                                               // byte
+            "paddb %%mm3, %%mm0          \n\t" // add LBCarrys to Avg for each
+                                               // byte
+            "pand  %%mm4, %%mm2          \n\t" // clear invalid bit 7 of each
+                                               // byte
+            "paddb %%mm1, %%mm0          \n\t" // add (Prev_row/2) to Avg for
+                                               // each byte
+            "addl $8, %%ebx              \n\t"
+            "paddb %%mm2, %%mm0          \n\t" // add (Raw/2) to Avg for each
+                                               // byte
+            "cmpl _MMXLength, %%ebx      \n\t"
+            "movq %%mm0, -8(%%edi,%%ebx,) \n\t"
+            "jb avg_Alp                  \n\t"
+
+            : // FIXASM: output regs/vars go here, e.g.:  "=m" (memory_var)
+
+            : // FIXASM: input regs, e.g.:  "c" (count), "S" (src), "D" (dest)
+
+            : "%ebx", "%edx", "%edi", "%esi" // CHECKASM: clobber list
+         );
+#endif /* 0 - NEVER REACHED */
+      }
+      break;
+
+   } // end switch (bpp)
+
+   __asm__ __volatile__ (
+      // MMX acceleration complete; now do clean-up
+      // check if any remaining bytes left to decode
+#ifdef __PIC__
+      "pushl %%ebx                 \n\t" // save index to Global Offset Table
+#endif
+      "movl _MMXLength, %%ebx      \n\t" // ebx:  x == offset bytes after MMX
+//pre "movl row, %%edi             \n\t" // edi:  Avg(x)
+      "cmpl _FullLength, %%ebx     \n\t" // test if offset at end of array
+      "jnb avg_end                 \n\t"
+
+      // do Avg decode for remaining bytes
+//pre "movl prev_row, %%esi        \n\t" // esi:  Prior(x)
+      "movl %%edi, %%edx           \n\t"
+//pre "subl bpp, %%edx             \n\t" // (bpp is preloaded into ecx)
+      "subl %%ecx, %%edx           \n\t" // edx:  Raw(x-bpp)
+      "xorl %%ecx, %%ecx           \n\t" // zero ecx before using cl & cx below
+
+   "avg_lp2:                       \n\t"
+      // Raw(x) = Avg(x) + ((Raw(x-bpp) + Prior(x))/2)
+      "xorl %%eax, %%eax           \n\t"
+      "movb (%%esi,%%ebx,), %%cl   \n\t" // load cl with Prior(x)
+      "movb (%%edx,%%ebx,), %%al   \n\t" // load al with Raw(x-bpp)
+      "addw %%cx, %%ax             \n\t"
+      "incl %%ebx                  \n\t"
+      "shrw %%ax                   \n\t" // divide by 2
+      "addb -1(%%edi,%%ebx,), %%al \n\t" // add Avg(x); -1 to offset inc ebx
+      "cmpl _FullLength, %%ebx     \n\t" // check if at end of array
+      "movb %%al, -1(%%edi,%%ebx,) \n\t" // write back Raw(x) [mov does not
+      "jb avg_lp2                  \n\t" //  affect flags; -1 to offset inc ebx]
+
+   "avg_end:                       \n\t"
+      "EMMS                        \n\t" // end MMX; prep for poss. FP instrs.
+#ifdef __PIC__
+      "popl %%ebx                  \n\t" // restore index to Global Offset Table
+#endif
+
+      : "=c" (dummy_value_c),            // output regs (dummy)
+        "=S" (dummy_value_S),
+        "=D" (dummy_value_D)
+
+      : "0" (bpp),       // ecx          // input regs
+        "1" (prev_row),  // esi
+        "2" (row)        // edi
+
+      : "%eax", "%edx"                   // clobber list
+#ifndef __PIC__
+      , "%ebx"
+#endif
+   );
+
+} /* end png_read_filter_row_mmx_avg() */
+#endif
+
+
+
+#ifdef PNG_THREAD_UNSAFE_OK
+//===========================================================================//
+//                                                                           //
+//         P N G _ R E A D _ F I L T E R _ R O W _ M M X _ P A E T H         //
+//                                                                           //
+//===========================================================================//
+
+// Optimized code for PNG Paeth filter decoder
+
+static void /* PRIVATE */
+png_read_filter_row_mmx_paeth(png_row_infop row_info, png_bytep row,
+                              png_bytep prev_row)
+{
+   int bpp;
+   int dummy_value_c;   // fix 'forbidden register 2 (cx) was spilled' error
+   int dummy_value_S;
+   int dummy_value_D;
+
+   bpp = (row_info->pixel_depth + 7) >> 3; // Get # bytes per pixel
+   _FullLength  = row_info->rowbytes; // # of bytes to filter
+
+   __asm__ __volatile__ (
+#ifdef __PIC__
+      "pushl %%ebx                 \n\t" // save index to Global Offset Table
+#endif
+      "xorl %%ebx, %%ebx           \n\t" // ebx:  x offset
+//pre "movl row, %%edi             \n\t"
+      "xorl %%edx, %%edx           \n\t" // edx:  x-bpp offset
+//pre "movl prev_row, %%esi        \n\t"
+      "xorl %%eax, %%eax           \n\t"
+
+      // Compute the Raw value for the first bpp bytes
+      // Note: the formula works out to be always
+      //   Paeth(x) = Raw(x) + Prior(x)      where x < bpp
+   "paeth_rlp:                     \n\t"
+      "movb (%%edi,%%ebx,), %%al   \n\t"
+      "addb (%%esi,%%ebx,), %%al   \n\t"
+      "incl %%ebx                  \n\t"
+//pre "cmpl bpp, %%ebx             \n\t" (bpp is preloaded into ecx)
+      "cmpl %%ecx, %%ebx           \n\t"
+      "movb %%al, -1(%%edi,%%ebx,) \n\t"
+      "jb paeth_rlp                \n\t"
+      // get # of bytes to alignment
+      "movl %%edi, _dif            \n\t" // take start of row
+      "addl %%ebx, _dif            \n\t" // add bpp
+      "xorl %%ecx, %%ecx           \n\t"
+      "addl $0xf, _dif             \n\t" // add 7 + 8 to incr past alignment
+                                         // boundary
+      "andl $0xfffffff8, _dif      \n\t" // mask to alignment boundary
+      "subl %%edi, _dif            \n\t" // subtract from start ==> value ebx
+                                         // at alignment
+      "jz paeth_go                 \n\t"
+      // fix alignment
+
+   "paeth_lp1:                     \n\t"
+      "xorl %%eax, %%eax           \n\t"
+      // pav = p - a = (a + b - c) - a = b - c
+      "movb (%%esi,%%ebx,), %%al   \n\t" // load Prior(x) into al
+      "movb (%%esi,%%edx,), %%cl   \n\t" // load Prior(x-bpp) into cl
+      "subl %%ecx, %%eax           \n\t" // subtract Prior(x-bpp)
+      "movl %%eax, _patemp         \n\t" // Save pav for later use
+      "xorl %%eax, %%eax           \n\t"
+      // pbv = p - b = (a + b - c) - b = a - c
+      "movb (%%edi,%%edx,), %%al   \n\t" // load Raw(x-bpp) into al
+      "subl %%ecx, %%eax           \n\t" // subtract Prior(x-bpp)
+      "movl %%eax, %%ecx           \n\t"
+      // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+      "addl _patemp, %%eax         \n\t" // pcv = pav + pbv
+      // pc = abs(pcv)
+      "testl $0x80000000, %%eax    \n\t"
+      "jz paeth_pca                \n\t"
+      "negl %%eax                  \n\t" // reverse sign of neg values
+
+   "paeth_pca:                     \n\t"
+      "movl %%eax, _pctemp         \n\t" // save pc for later use
+      // pb = abs(pbv)
+      "testl $0x80000000, %%ecx    \n\t"
+      "jz paeth_pba                \n\t"
+      "negl %%ecx                  \n\t" // reverse sign of neg values
+
+   "paeth_pba:                     \n\t"
+      "movl %%ecx, _pbtemp         \n\t" // save pb for later use
+      // pa = abs(pav)
+      "movl _patemp, %%eax         \n\t"
+      "testl $0x80000000, %%eax    \n\t"
+      "jz paeth_paa                \n\t"
+      "negl %%eax                  \n\t" // reverse sign of neg values
+
+   "paeth_paa:                     \n\t"
+      "movl %%eax, _patemp         \n\t" // save pa for later use
+      // test if pa <= pb
+      "cmpl %%ecx, %%eax           \n\t"
+      "jna paeth_abb               \n\t"
+      // pa > pb; now test if pb <= pc
+      "cmpl _pctemp, %%ecx         \n\t"
+      "jna paeth_bbc               \n\t"
+      // pb > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+      "movb (%%esi,%%edx,), %%cl   \n\t" // load Prior(x-bpp) into cl
+      "jmp paeth_paeth             \n\t"
+
+   "paeth_bbc:                     \n\t"
+      // pb <= pc; Raw(x) = Paeth(x) + Prior(x)
+      "movb (%%esi,%%ebx,), %%cl   \n\t" // load Prior(x) into cl
+      "jmp paeth_paeth             \n\t"
+
+   "paeth_abb:                     \n\t"
+      // pa <= pb; now test if pa <= pc
+      "cmpl _pctemp, %%eax         \n\t"
+      "jna paeth_abc               \n\t"
+      // pa > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+      "movb (%%esi,%%edx,), %%cl   \n\t" // load Prior(x-bpp) into cl
+      "jmp paeth_paeth             \n\t"
+
+   "paeth_abc:                     \n\t"
+      // pa <= pc; Raw(x) = Paeth(x) + Raw(x-bpp)
+      "movb (%%edi,%%edx,), %%cl   \n\t" // load Raw(x-bpp) into cl
+
+   "paeth_paeth:                   \n\t"
+      "incl %%ebx                  \n\t"
+      "incl %%edx                  \n\t"
+      // Raw(x) = (Paeth(x) + Paeth_Predictor( a, b, c )) mod 256
+      "addb %%cl, -1(%%edi,%%ebx,) \n\t"
+      "cmpl _dif, %%ebx            \n\t"
+      "jb paeth_lp1                \n\t"
+
+   "paeth_go:                      \n\t"
+      "movl _FullLength, %%ecx     \n\t"
+      "movl %%ecx, %%eax           \n\t"
+      "subl %%ebx, %%eax           \n\t" // subtract alignment fix
+      "andl $0x00000007, %%eax     \n\t" // calc bytes over mult of 8
+      "subl %%eax, %%ecx           \n\t" // drop over bytes from original length
+      "movl %%ecx, _MMXLength      \n\t"
+#ifdef __PIC__
+      "popl %%ebx                  \n\t" // restore index to Global Offset Table
+#endif
+
+      : "=c" (dummy_value_c),            // output regs (dummy)
+        "=S" (dummy_value_S),
+        "=D" (dummy_value_D)
+
+      : "0" (bpp),       // ecx          // input regs
+        "1" (prev_row),  // esi
+        "2" (row)        // edi
+
+      : "%eax", "%edx"                   // clobber list
+#ifndef __PIC__
+      , "%ebx"
+#endif
+   );
+
+   // now do the math for the rest of the row
+   switch (bpp)
+   {
+      case 3:
+      {
+         _ActiveMask.use = 0x0000000000ffffffLL;
+         _ActiveMaskEnd.use = 0xffff000000000000LL;
+         _ShiftBpp.use = 24;    // == bpp(3) * 8
+         _ShiftRem.use = 40;    // == 64 - 24
+
+         __asm__ __volatile__ (
+            "movl _dif, %%ecx            \n\t"
+// preload  "movl row, %%edi             \n\t"
+// preload  "movl prev_row, %%esi        \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%ecx,), %%mm1 \n\t"
+         "paeth_3lp:                     \n\t"
+            "psrlq _ShiftRem, %%mm1      \n\t" // shift last 3 bytes to 1st
+                                               // 3 bytes
+            "movq (%%esi,%%ecx,), %%mm2  \n\t" // load b=Prior(x)
+            "punpcklbw %%mm0, %%mm1      \n\t" // unpack High bytes of a
+            "movq -8(%%esi,%%ecx,), %%mm3 \n\t" // prep c=Prior(x-bpp) bytes
+            "punpcklbw %%mm0, %%mm2      \n\t" // unpack High bytes of b
+            "psrlq _ShiftRem, %%mm3      \n\t" // shift last 3 bytes to 1st
+                                               // 3 bytes
+            // pav = p - a = (a + b - c) - a = b - c
+            "movq %%mm2, %%mm4           \n\t"
+            "punpcklbw %%mm0, %%mm3      \n\t" // unpack High bytes of c
+            // pbv = p - b = (a + b - c) - b = a - c
+            "movq %%mm1, %%mm5           \n\t"
+            "psubw %%mm3, %%mm4          \n\t"
+            "pxor %%mm7, %%mm7           \n\t"
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            "movq %%mm4, %%mm6           \n\t"
+            "psubw %%mm3, %%mm5          \n\t"
+
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            "pcmpgtw %%mm4, %%mm0        \n\t" // create mask pav bytes < 0
+            "paddw %%mm5, %%mm6          \n\t"
+            "pand %%mm4, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "pcmpgtw %%mm5, %%mm7        \n\t" // create mask pbv bytes < 0
+            "psubw %%mm0, %%mm4          \n\t"
+            "pand %%mm5, %%mm7           \n\t" // only pbv bytes < 0 in mm0
+            "psubw %%mm0, %%mm4          \n\t"
+            "psubw %%mm7, %%mm5          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "pcmpgtw %%mm6, %%mm0        \n\t" // create mask pcv bytes < 0
+            "pand %%mm6, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "psubw %%mm7, %%mm5          \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            //  test pa <= pb
+            "movq %%mm4, %%mm7           \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            "pcmpgtw %%mm5, %%mm7        \n\t" // pa > pb?
+            "movq %%mm7, %%mm0           \n\t"
+            // use mm7 mask to merge pa & pb
+            "pand %%mm7, %%mm5           \n\t"
+            // use mm0 mask copy to merge a & b
+            "pand %%mm0, %%mm2           \n\t"
+            "pandn %%mm4, %%mm7          \n\t"
+            "pandn %%mm1, %%mm0          \n\t"
+            "paddw %%mm5, %%mm7          \n\t"
+            "paddw %%mm2, %%mm0          \n\t"
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            "pcmpgtw %%mm6, %%mm7        \n\t" // pab > pc?
+            "pxor %%mm1, %%mm1           \n\t"
+            "pand %%mm7, %%mm3           \n\t"
+            "pandn %%mm0, %%mm7          \n\t"
+            "paddw %%mm3, %%mm7          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "packuswb %%mm1, %%mm7       \n\t"
+            "movq (%%esi,%%ecx,), %%mm3  \n\t" // load c=Prior(x-bpp)
+            "pand _ActiveMask, %%mm7     \n\t"
+            "movq %%mm3, %%mm2           \n\t" // load b=Prior(x) step 1
+            "paddb (%%edi,%%ecx,), %%mm7 \n\t" // add Paeth predictor with Raw(x)
+            "punpcklbw %%mm0, %%mm3      \n\t" // unpack High bytes of c
+            "movq %%mm7, (%%edi,%%ecx,)  \n\t" // write back updated value
+            "movq %%mm7, %%mm1           \n\t" // now mm1 will be used as
+                                               // Raw(x-bpp)
+            // now do Paeth for 2nd set of bytes (3-5)
+            "psrlq _ShiftBpp, %%mm2      \n\t" // load b=Prior(x) step 2
+            "punpcklbw %%mm0, %%mm1      \n\t" // unpack High bytes of a
+            "pxor %%mm7, %%mm7           \n\t"
+            "punpcklbw %%mm0, %%mm2      \n\t" // unpack High bytes of b
+            // pbv = p - b = (a + b - c) - b = a - c
+            "movq %%mm1, %%mm5           \n\t"
+            // pav = p - a = (a + b - c) - a = b - c
+            "movq %%mm2, %%mm4           \n\t"
+            "psubw %%mm3, %%mm5          \n\t"
+            "psubw %%mm3, %%mm4          \n\t"
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) =
+            //       pav + pbv = pbv + pav
+            "movq %%mm5, %%mm6           \n\t"
+            "paddw %%mm4, %%mm6          \n\t"
+
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            "pcmpgtw %%mm5, %%mm0        \n\t" // create mask pbv bytes < 0
+            "pcmpgtw %%mm4, %%mm7        \n\t" // create mask pav bytes < 0
+            "pand %%mm5, %%mm0           \n\t" // only pbv bytes < 0 in mm0
+            "pand %%mm4, %%mm7           \n\t" // only pav bytes < 0 in mm7
+            "psubw %%mm0, %%mm5          \n\t"
+            "psubw %%mm7, %%mm4          \n\t"
+            "psubw %%mm0, %%mm5          \n\t"
+            "psubw %%mm7, %%mm4          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "pcmpgtw %%mm6, %%mm0        \n\t" // create mask pcv bytes < 0
+            "pand %%mm6, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "psubw %%mm0, %%mm6          \n\t"
+            //  test pa <= pb
+            "movq %%mm4, %%mm7           \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            "pcmpgtw %%mm5, %%mm7        \n\t" // pa > pb?
+            "movq %%mm7, %%mm0           \n\t"
+            // use mm7 mask to merge pa & pb
+            "pand %%mm7, %%mm5           \n\t"
+            // use mm0 mask copy to merge a & b
+            "pand %%mm0, %%mm2           \n\t"
+            "pandn %%mm4, %%mm7          \n\t"
+            "pandn %%mm1, %%mm0          \n\t"
+            "paddw %%mm5, %%mm7          \n\t"
+            "paddw %%mm2, %%mm0          \n\t"
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            "pcmpgtw %%mm6, %%mm7        \n\t" // pab > pc?
+            "movq (%%esi,%%ecx,), %%mm2  \n\t" // load b=Prior(x)
+            "pand %%mm7, %%mm3           \n\t"
+            "pandn %%mm0, %%mm7          \n\t"
+            "pxor %%mm1, %%mm1           \n\t"
+            "paddw %%mm3, %%mm7          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "packuswb %%mm1, %%mm7       \n\t"
+            "movq %%mm2, %%mm3           \n\t" // load c=Prior(x-bpp) step 1
+            "pand _ActiveMask, %%mm7     \n\t"
+            "punpckhbw %%mm0, %%mm2      \n\t" // unpack High bytes of b
+            "psllq _ShiftBpp, %%mm7      \n\t" // shift bytes to 2nd group of
+                                               // 3 bytes
+             // pav = p - a = (a + b - c) - a = b - c
+            "movq %%mm2, %%mm4           \n\t"
+            "paddb (%%edi,%%ecx,), %%mm7 \n\t" // add Paeth predictor with Raw(x)
+            "psllq _ShiftBpp, %%mm3      \n\t" // load c=Prior(x-bpp) step 2
+            "movq %%mm7, (%%edi,%%ecx,)  \n\t" // write back updated value
+            "movq %%mm7, %%mm1           \n\t"
+            "punpckhbw %%mm0, %%mm3      \n\t" // unpack High bytes of c
+            "psllq _ShiftBpp, %%mm1      \n\t" // shift bytes
+                                    // now mm1 will be used as Raw(x-bpp)
+            // now do Paeth for 3rd, and final, set of bytes (6-7)
+            "pxor %%mm7, %%mm7           \n\t"
+            "punpckhbw %%mm0, %%mm1      \n\t" // unpack High bytes of a
+            "psubw %%mm3, %%mm4          \n\t"
+            // pbv = p - b = (a + b - c) - b = a - c
+            "movq %%mm1, %%mm5           \n\t"
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            "movq %%mm4, %%mm6           \n\t"
+            "psubw %%mm3, %%mm5          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "paddw %%mm5, %%mm6          \n\t"
+
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            "pcmpgtw %%mm4, %%mm0        \n\t" // create mask pav bytes < 0
+            "pcmpgtw %%mm5, %%mm7        \n\t" // create mask pbv bytes < 0
+            "pand %%mm4, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "pand %%mm5, %%mm7           \n\t" // only pbv bytes < 0 in mm0
+            "psubw %%mm0, %%mm4          \n\t"
+            "psubw %%mm7, %%mm5          \n\t"
+            "psubw %%mm0, %%mm4          \n\t"
+            "psubw %%mm7, %%mm5          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "pcmpgtw %%mm6, %%mm0        \n\t" // create mask pcv bytes < 0
+            "pand %%mm6, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "psubw %%mm0, %%mm6          \n\t"
+            //  test pa <= pb
+            "movq %%mm4, %%mm7           \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            "pcmpgtw %%mm5, %%mm7        \n\t" // pa > pb?
+            "movq %%mm7, %%mm0           \n\t"
+            // use mm0 mask copy to merge a & b
+            "pand %%mm0, %%mm2           \n\t"
+            // use mm7 mask to merge pa & pb
+            "pand %%mm7, %%mm5           \n\t"
+            "pandn %%mm1, %%mm0          \n\t"
+            "pandn %%mm4, %%mm7          \n\t"
+            "paddw %%mm2, %%mm0          \n\t"
+            "paddw %%mm5, %%mm7          \n\t"
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            "pcmpgtw %%mm6, %%mm7        \n\t" // pab > pc?
+            "pand %%mm7, %%mm3           \n\t"
+            "pandn %%mm0, %%mm7          \n\t"
+            "paddw %%mm3, %%mm7          \n\t"
+            "pxor %%mm1, %%mm1           \n\t"
+            "packuswb %%mm7, %%mm1       \n\t"
+            // step ecx to next set of 8 bytes and repeat loop til done
+            "addl $8, %%ecx              \n\t"
+            "pand _ActiveMaskEnd, %%mm1  \n\t"
+            "paddb -8(%%edi,%%ecx,), %%mm1 \n\t" // add Paeth predictor with
+                                                 // Raw(x)
+
+            "cmpl _MMXLength, %%ecx      \n\t"
+            "pxor %%mm0, %%mm0           \n\t" // pxor does not affect flags
+            "movq %%mm1, -8(%%edi,%%ecx,) \n\t" // write back updated value
+                                 // mm1 will be used as Raw(x-bpp) next loop
+                           // mm3 ready to be used as Prior(x-bpp) next loop
+            "jb paeth_3lp                \n\t"
+
+            : "=S" (dummy_value_S),             // output regs (dummy)
+              "=D" (dummy_value_D)
+
+            : "0" (prev_row),  // esi           // input regs
+              "1" (row)        // edi
+
+            : "%ecx"                            // clobber list
+#if 0  /* %mm0, ..., %mm7 not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1", "%mm2", "%mm3"
+            , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+         );
+      }
+      break;  // end 3 bpp
+
+      case 6:
+      //case 7:   // GRR BOGUS
+      //case 5:   // GRR BOGUS
+      {
+         _ActiveMask.use  = 0x00000000ffffffffLL;
+         _ActiveMask2.use = 0xffffffff00000000LL;
+         _ShiftBpp.use = bpp << 3;    // == bpp * 8
+         _ShiftRem.use = 64 - _ShiftBpp.use;
+
+         __asm__ __volatile__ (
+            "movl _dif, %%ecx            \n\t"
+// preload  "movl row, %%edi             \n\t"
+// preload  "movl prev_row, %%esi        \n\t"
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%ecx,), %%mm1 \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+
+         "paeth_6lp:                     \n\t"
+            // must shift to position Raw(x-bpp) data
+            "psrlq _ShiftRem, %%mm1      \n\t"
+            // do first set of 4 bytes
+            "movq -8(%%esi,%%ecx,), %%mm3 \n\t" // read c=Prior(x-bpp) bytes
+            "punpcklbw %%mm0, %%mm1      \n\t" // unpack Low bytes of a
+            "movq (%%esi,%%ecx,), %%mm2  \n\t" // load b=Prior(x)
+            "punpcklbw %%mm0, %%mm2      \n\t" // unpack Low bytes of b
+            // must shift to position Prior(x-bpp) data
+            "psrlq _ShiftRem, %%mm3      \n\t"
+            // pav = p - a = (a + b - c) - a = b - c
+            "movq %%mm2, %%mm4           \n\t"
+            "punpcklbw %%mm0, %%mm3      \n\t" // unpack Low bytes of c
+            // pbv = p - b = (a + b - c) - b = a - c
+            "movq %%mm1, %%mm5           \n\t"
+            "psubw %%mm3, %%mm4          \n\t"
+            "pxor %%mm7, %%mm7           \n\t"
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            "movq %%mm4, %%mm6           \n\t"
+            "psubw %%mm3, %%mm5          \n\t"
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            "pcmpgtw %%mm4, %%mm0        \n\t" // create mask pav bytes < 0
+            "paddw %%mm5, %%mm6          \n\t"
+            "pand %%mm4, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "pcmpgtw %%mm5, %%mm7        \n\t" // create mask pbv bytes < 0
+            "psubw %%mm0, %%mm4          \n\t"
+            "pand %%mm5, %%mm7           \n\t" // only pbv bytes < 0 in mm0
+            "psubw %%mm0, %%mm4          \n\t"
+            "psubw %%mm7, %%mm5          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "pcmpgtw %%mm6, %%mm0        \n\t" // create mask pcv bytes < 0
+            "pand %%mm6, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "psubw %%mm7, %%mm5          \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            //  test pa <= pb
+            "movq %%mm4, %%mm7           \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            "pcmpgtw %%mm5, %%mm7        \n\t" // pa > pb?
+            "movq %%mm7, %%mm0           \n\t"
+            // use mm7 mask to merge pa & pb
+            "pand %%mm7, %%mm5           \n\t"
+            // use mm0 mask copy to merge a & b
+            "pand %%mm0, %%mm2           \n\t"
+            "pandn %%mm4, %%mm7          \n\t"
+            "pandn %%mm1, %%mm0          \n\t"
+            "paddw %%mm5, %%mm7          \n\t"
+            "paddw %%mm2, %%mm0          \n\t"
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            "pcmpgtw %%mm6, %%mm7        \n\t" // pab > pc?
+            "pxor %%mm1, %%mm1           \n\t"
+            "pand %%mm7, %%mm3           \n\t"
+            "pandn %%mm0, %%mm7          \n\t"
+            "paddw %%mm3, %%mm7          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "packuswb %%mm1, %%mm7       \n\t"
+            "movq -8(%%esi,%%ecx,), %%mm3 \n\t" // load c=Prior(x-bpp)
+            "pand _ActiveMask, %%mm7     \n\t"
+            "psrlq _ShiftRem, %%mm3      \n\t"
+            "movq (%%esi,%%ecx,), %%mm2  \n\t" // load b=Prior(x) step 1
+            "paddb (%%edi,%%ecx,), %%mm7 \n\t" // add Paeth predictor and Raw(x)
+            "movq %%mm2, %%mm6           \n\t"
+            "movq %%mm7, (%%edi,%%ecx,)  \n\t" // write back updated value
+            "movq -8(%%edi,%%ecx,), %%mm1 \n\t"
+            "psllq _ShiftBpp, %%mm6      \n\t"
+            "movq %%mm7, %%mm5           \n\t"
+            "psrlq _ShiftRem, %%mm1      \n\t"
+            "por %%mm6, %%mm3            \n\t"
+            "psllq _ShiftBpp, %%mm5      \n\t"
+            "punpckhbw %%mm0, %%mm3      \n\t" // unpack High bytes of c
+            "por %%mm5, %%mm1            \n\t"
+            // do second set of 4 bytes
+            "punpckhbw %%mm0, %%mm2      \n\t" // unpack High bytes of b
+            "punpckhbw %%mm0, %%mm1      \n\t" // unpack High bytes of a
+            // pav = p - a = (a + b - c) - a = b - c
+            "movq %%mm2, %%mm4           \n\t"
+            // pbv = p - b = (a + b - c) - b = a - c
+            "movq %%mm1, %%mm5           \n\t"
+            "psubw %%mm3, %%mm4          \n\t"
+            "pxor %%mm7, %%mm7           \n\t"
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            "movq %%mm4, %%mm6           \n\t"
+            "psubw %%mm3, %%mm5          \n\t"
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            "pcmpgtw %%mm4, %%mm0        \n\t" // create mask pav bytes < 0
+            "paddw %%mm5, %%mm6          \n\t"
+            "pand %%mm4, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "pcmpgtw %%mm5, %%mm7        \n\t" // create mask pbv bytes < 0
+            "psubw %%mm0, %%mm4          \n\t"
+            "pand %%mm5, %%mm7           \n\t" // only pbv bytes < 0 in mm0
+            "psubw %%mm0, %%mm4          \n\t"
+            "psubw %%mm7, %%mm5          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "pcmpgtw %%mm6, %%mm0        \n\t" // create mask pcv bytes < 0
+            "pand %%mm6, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "psubw %%mm7, %%mm5          \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            //  test pa <= pb
+            "movq %%mm4, %%mm7           \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            "pcmpgtw %%mm5, %%mm7        \n\t" // pa > pb?
+            "movq %%mm7, %%mm0           \n\t"
+            // use mm7 mask to merge pa & pb
+            "pand %%mm7, %%mm5           \n\t"
+            // use mm0 mask copy to merge a & b
+            "pand %%mm0, %%mm2           \n\t"
+            "pandn %%mm4, %%mm7          \n\t"
+            "pandn %%mm1, %%mm0          \n\t"
+            "paddw %%mm5, %%mm7          \n\t"
+            "paddw %%mm2, %%mm0          \n\t"
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            "pcmpgtw %%mm6, %%mm7        \n\t" // pab > pc?
+            "pxor %%mm1, %%mm1           \n\t"
+            "pand %%mm7, %%mm3           \n\t"
+            "pandn %%mm0, %%mm7          \n\t"
+            "pxor %%mm1, %%mm1           \n\t"
+            "paddw %%mm3, %%mm7          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            // step ecx to next set of 8 bytes and repeat loop til done
+            "addl $8, %%ecx              \n\t"
+            "packuswb %%mm7, %%mm1       \n\t"
+            "paddb -8(%%edi,%%ecx,), %%mm1 \n\t" // add Paeth predictor with Raw(x)
+            "cmpl _MMXLength, %%ecx      \n\t"
+            "movq %%mm1, -8(%%edi,%%ecx,) \n\t" // write back updated value
+                                // mm1 will be used as Raw(x-bpp) next loop
+            "jb paeth_6lp                \n\t"
+
+            : "=S" (dummy_value_S),             // output regs (dummy)
+              "=D" (dummy_value_D)
+
+            : "0" (prev_row),  // esi           // input regs
+              "1" (row)        // edi
+
+            : "%ecx"                            // clobber list
+#if 0  /* %mm0, ..., %mm7 not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1", "%mm2", "%mm3"
+            , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+         );
+      }
+      break;  // end 6 bpp
+
+      case 4:
+      {
+         _ActiveMask.use  = 0x00000000ffffffffLL;
+
+         __asm__ __volatile__ (
+            "movl _dif, %%ecx            \n\t"
+// preload  "movl row, %%edi             \n\t"
+// preload  "movl prev_row, %%esi        \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%ecx,), %%mm1 \n\t" // only time should need to read
+                                     //  a=Raw(x-bpp) bytes
+         "paeth_4lp:                     \n\t"
+            // do first set of 4 bytes
+            "movq -8(%%esi,%%ecx,), %%mm3 \n\t" // read c=Prior(x-bpp) bytes
+            "punpckhbw %%mm0, %%mm1      \n\t" // unpack Low bytes of a
+            "movq (%%esi,%%ecx,), %%mm2  \n\t" // load b=Prior(x)
+            "punpcklbw %%mm0, %%mm2      \n\t" // unpack High bytes of b
+            // pav = p - a = (a + b - c) - a = b - c
+            "movq %%mm2, %%mm4           \n\t"
+            "punpckhbw %%mm0, %%mm3      \n\t" // unpack High bytes of c
+            // pbv = p - b = (a + b - c) - b = a - c
+            "movq %%mm1, %%mm5           \n\t"
+            "psubw %%mm3, %%mm4          \n\t"
+            "pxor %%mm7, %%mm7           \n\t"
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            "movq %%mm4, %%mm6           \n\t"
+            "psubw %%mm3, %%mm5          \n\t"
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            "pcmpgtw %%mm4, %%mm0        \n\t" // create mask pav bytes < 0
+            "paddw %%mm5, %%mm6          \n\t"
+            "pand %%mm4, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "pcmpgtw %%mm5, %%mm7        \n\t" // create mask pbv bytes < 0
+            "psubw %%mm0, %%mm4          \n\t"
+            "pand %%mm5, %%mm7           \n\t" // only pbv bytes < 0 in mm0
+            "psubw %%mm0, %%mm4          \n\t"
+            "psubw %%mm7, %%mm5          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "pcmpgtw %%mm6, %%mm0        \n\t" // create mask pcv bytes < 0
+            "pand %%mm6, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "psubw %%mm7, %%mm5          \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            //  test pa <= pb
+            "movq %%mm4, %%mm7           \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            "pcmpgtw %%mm5, %%mm7        \n\t" // pa > pb?
+            "movq %%mm7, %%mm0           \n\t"
+            // use mm7 mask to merge pa & pb
+            "pand %%mm7, %%mm5           \n\t"
+            // use mm0 mask copy to merge a & b
+            "pand %%mm0, %%mm2           \n\t"
+            "pandn %%mm4, %%mm7          \n\t"
+            "pandn %%mm1, %%mm0          \n\t"
+            "paddw %%mm5, %%mm7          \n\t"
+            "paddw %%mm2, %%mm0          \n\t"
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            "pcmpgtw %%mm6, %%mm7        \n\t" // pab > pc?
+            "pxor %%mm1, %%mm1           \n\t"
+            "pand %%mm7, %%mm3           \n\t"
+            "pandn %%mm0, %%mm7          \n\t"
+            "paddw %%mm3, %%mm7          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "packuswb %%mm1, %%mm7       \n\t"
+            "movq (%%esi,%%ecx,), %%mm3  \n\t" // load c=Prior(x-bpp)
+            "pand _ActiveMask, %%mm7     \n\t"
+            "movq %%mm3, %%mm2           \n\t" // load b=Prior(x) step 1
+            "paddb (%%edi,%%ecx,), %%mm7 \n\t" // add Paeth predictor with Raw(x)
+            "punpcklbw %%mm0, %%mm3      \n\t" // unpack High bytes of c
+            "movq %%mm7, (%%edi,%%ecx,)  \n\t" // write back updated value
+            "movq %%mm7, %%mm1           \n\t" // now mm1 will be used as Raw(x-bpp)
+            // do second set of 4 bytes
+            "punpckhbw %%mm0, %%mm2      \n\t" // unpack Low bytes of b
+            "punpcklbw %%mm0, %%mm1      \n\t" // unpack Low bytes of a
+            // pav = p - a = (a + b - c) - a = b - c
+            "movq %%mm2, %%mm4           \n\t"
+            // pbv = p - b = (a + b - c) - b = a - c
+            "movq %%mm1, %%mm5           \n\t"
+            "psubw %%mm3, %%mm4          \n\t"
+            "pxor %%mm7, %%mm7           \n\t"
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            "movq %%mm4, %%mm6           \n\t"
+            "psubw %%mm3, %%mm5          \n\t"
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            "pcmpgtw %%mm4, %%mm0        \n\t" // create mask pav bytes < 0
+            "paddw %%mm5, %%mm6          \n\t"
+            "pand %%mm4, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "pcmpgtw %%mm5, %%mm7        \n\t" // create mask pbv bytes < 0
+            "psubw %%mm0, %%mm4          \n\t"
+            "pand %%mm5, %%mm7           \n\t" // only pbv bytes < 0 in mm0
+            "psubw %%mm0, %%mm4          \n\t"
+            "psubw %%mm7, %%mm5          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "pcmpgtw %%mm6, %%mm0        \n\t" // create mask pcv bytes < 0
+            "pand %%mm6, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "psubw %%mm7, %%mm5          \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            //  test pa <= pb
+            "movq %%mm4, %%mm7           \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            "pcmpgtw %%mm5, %%mm7        \n\t" // pa > pb?
+            "movq %%mm7, %%mm0           \n\t"
+            // use mm7 mask to merge pa & pb
+            "pand %%mm7, %%mm5           \n\t"
+            // use mm0 mask copy to merge a & b
+            "pand %%mm0, %%mm2           \n\t"
+            "pandn %%mm4, %%mm7          \n\t"
+            "pandn %%mm1, %%mm0          \n\t"
+            "paddw %%mm5, %%mm7          \n\t"
+            "paddw %%mm2, %%mm0          \n\t"
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            "pcmpgtw %%mm6, %%mm7        \n\t" // pab > pc?
+            "pxor %%mm1, %%mm1           \n\t"
+            "pand %%mm7, %%mm3           \n\t"
+            "pandn %%mm0, %%mm7          \n\t"
+            "pxor %%mm1, %%mm1           \n\t"
+            "paddw %%mm3, %%mm7          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            // step ecx to next set of 8 bytes and repeat loop til done
+            "addl $8, %%ecx              \n\t"
+            "packuswb %%mm7, %%mm1       \n\t"
+            "paddb -8(%%edi,%%ecx,), %%mm1 \n\t" // add predictor with Raw(x)
+            "cmpl _MMXLength, %%ecx      \n\t"
+            "movq %%mm1, -8(%%edi,%%ecx,) \n\t" // write back updated value
+                                // mm1 will be used as Raw(x-bpp) next loop
+            "jb paeth_4lp                \n\t"
+
+            : "=S" (dummy_value_S),             // output regs (dummy)
+              "=D" (dummy_value_D)
+
+            : "0" (prev_row),  // esi           // input regs
+              "1" (row)        // edi
+
+            : "%ecx"                            // clobber list
+#if 0  /* %mm0, ..., %mm7 not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1", "%mm2", "%mm3"
+            , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+         );
+      }
+      break;  // end 4 bpp
+
+      case 8:                          // bpp == 8
+      {
+         _ActiveMask.use  = 0x00000000ffffffffLL;
+
+         __asm__ __volatile__ (
+            "movl _dif, %%ecx            \n\t"
+// preload  "movl row, %%edi             \n\t"
+// preload  "movl prev_row, %%esi        \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%ecx,), %%mm1 \n\t" // only time should need to read
+                                       //  a=Raw(x-bpp) bytes
+         "paeth_8lp:                     \n\t"
+            // do first set of 4 bytes
+            "movq -8(%%esi,%%ecx,), %%mm3 \n\t" // read c=Prior(x-bpp) bytes
+            "punpcklbw %%mm0, %%mm1      \n\t" // unpack Low bytes of a
+            "movq (%%esi,%%ecx,), %%mm2  \n\t" // load b=Prior(x)
+            "punpcklbw %%mm0, %%mm2      \n\t" // unpack Low bytes of b
+            // pav = p - a = (a + b - c) - a = b - c
+            "movq %%mm2, %%mm4           \n\t"
+            "punpcklbw %%mm0, %%mm3      \n\t" // unpack Low bytes of c
+            // pbv = p - b = (a + b - c) - b = a - c
+            "movq %%mm1, %%mm5           \n\t"
+            "psubw %%mm3, %%mm4          \n\t"
+            "pxor %%mm7, %%mm7           \n\t"
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            "movq %%mm4, %%mm6           \n\t"
+            "psubw %%mm3, %%mm5          \n\t"
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            "pcmpgtw %%mm4, %%mm0        \n\t" // create mask pav bytes < 0
+            "paddw %%mm5, %%mm6          \n\t"
+            "pand %%mm4, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "pcmpgtw %%mm5, %%mm7        \n\t" // create mask pbv bytes < 0
+            "psubw %%mm0, %%mm4          \n\t"
+            "pand %%mm5, %%mm7           \n\t" // only pbv bytes < 0 in mm0
+            "psubw %%mm0, %%mm4          \n\t"
+            "psubw %%mm7, %%mm5          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "pcmpgtw %%mm6, %%mm0        \n\t" // create mask pcv bytes < 0
+            "pand %%mm6, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "psubw %%mm7, %%mm5          \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            //  test pa <= pb
+            "movq %%mm4, %%mm7           \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            "pcmpgtw %%mm5, %%mm7        \n\t" // pa > pb?
+            "movq %%mm7, %%mm0           \n\t"
+            // use mm7 mask to merge pa & pb
+            "pand %%mm7, %%mm5           \n\t"
+            // use mm0 mask copy to merge a & b
+            "pand %%mm0, %%mm2           \n\t"
+            "pandn %%mm4, %%mm7          \n\t"
+            "pandn %%mm1, %%mm0          \n\t"
+            "paddw %%mm5, %%mm7          \n\t"
+            "paddw %%mm2, %%mm0          \n\t"
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            "pcmpgtw %%mm6, %%mm7        \n\t" // pab > pc?
+            "pxor %%mm1, %%mm1           \n\t"
+            "pand %%mm7, %%mm3           \n\t"
+            "pandn %%mm0, %%mm7          \n\t"
+            "paddw %%mm3, %%mm7          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "packuswb %%mm1, %%mm7       \n\t"
+            "movq -8(%%esi,%%ecx,), %%mm3 \n\t" // read c=Prior(x-bpp) bytes
+            "pand _ActiveMask, %%mm7     \n\t"
+            "movq (%%esi,%%ecx,), %%mm2  \n\t" // load b=Prior(x)
+            "paddb (%%edi,%%ecx,), %%mm7 \n\t" // add Paeth predictor with Raw(x)
+            "punpckhbw %%mm0, %%mm3      \n\t" // unpack High bytes of c
+            "movq %%mm7, (%%edi,%%ecx,)  \n\t" // write back updated value
+            "movq -8(%%edi,%%ecx,), %%mm1 \n\t" // read a=Raw(x-bpp) bytes
+
+            // do second set of 4 bytes
+            "punpckhbw %%mm0, %%mm2      \n\t" // unpack High bytes of b
+            "punpckhbw %%mm0, %%mm1      \n\t" // unpack High bytes of a
+            // pav = p - a = (a + b - c) - a = b - c
+            "movq %%mm2, %%mm4           \n\t"
+            // pbv = p - b = (a + b - c) - b = a - c
+            "movq %%mm1, %%mm5           \n\t"
+            "psubw %%mm3, %%mm4          \n\t"
+            "pxor %%mm7, %%mm7           \n\t"
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            "movq %%mm4, %%mm6           \n\t"
+            "psubw %%mm3, %%mm5          \n\t"
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            "pcmpgtw %%mm4, %%mm0        \n\t" // create mask pav bytes < 0
+            "paddw %%mm5, %%mm6          \n\t"
+            "pand %%mm4, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "pcmpgtw %%mm5, %%mm7        \n\t" // create mask pbv bytes < 0
+            "psubw %%mm0, %%mm4          \n\t"
+            "pand %%mm5, %%mm7           \n\t" // only pbv bytes < 0 in mm0
+            "psubw %%mm0, %%mm4          \n\t"
+            "psubw %%mm7, %%mm5          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            "pcmpgtw %%mm6, %%mm0        \n\t" // create mask pcv bytes < 0
+            "pand %%mm6, %%mm0           \n\t" // only pav bytes < 0 in mm7
+            "psubw %%mm7, %%mm5          \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            //  test pa <= pb
+            "movq %%mm4, %%mm7           \n\t"
+            "psubw %%mm0, %%mm6          \n\t"
+            "pcmpgtw %%mm5, %%mm7        \n\t" // pa > pb?
+            "movq %%mm7, %%mm0           \n\t"
+            // use mm7 mask to merge pa & pb
+            "pand %%mm7, %%mm5           \n\t"
+            // use mm0 mask copy to merge a & b
+            "pand %%mm0, %%mm2           \n\t"
+            "pandn %%mm4, %%mm7          \n\t"
+            "pandn %%mm1, %%mm0          \n\t"
+            "paddw %%mm5, %%mm7          \n\t"
+            "paddw %%mm2, %%mm0          \n\t"
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            "pcmpgtw %%mm6, %%mm7        \n\t" // pab > pc?
+            "pxor %%mm1, %%mm1           \n\t"
+            "pand %%mm7, %%mm3           \n\t"
+            "pandn %%mm0, %%mm7          \n\t"
+            "pxor %%mm1, %%mm1           \n\t"
+            "paddw %%mm3, %%mm7          \n\t"
+            "pxor %%mm0, %%mm0           \n\t"
+            // step ecx to next set of 8 bytes and repeat loop til done
+            "addl $8, %%ecx              \n\t"
+            "packuswb %%mm7, %%mm1       \n\t"
+            "paddb -8(%%edi,%%ecx,), %%mm1 \n\t" // add Paeth predictor with Raw(x)
+            "cmpl _MMXLength, %%ecx      \n\t"
+            "movq %%mm1, -8(%%edi,%%ecx,) \n\t" // write back updated value
+                            // mm1 will be used as Raw(x-bpp) next loop
+            "jb paeth_8lp                \n\t"
+
+            : "=S" (dummy_value_S),             // output regs (dummy)
+              "=D" (dummy_value_D)
+
+            : "0" (prev_row),  // esi           // input regs
+              "1" (row)        // edi
+
+            : "%ecx"                            // clobber list
+#if 0  /* %mm0, ..., %mm7 not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1", "%mm2", "%mm3"
+            , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+         );
+      }
+      break;  // end 8 bpp
+
+      case 1:                // bpp = 1
+      case 2:                // bpp = 2
+      default:               // bpp > 8
+      {
+         __asm__ __volatile__ (
+#ifdef __PIC__
+            "pushl %%ebx                 \n\t" // save Global Offset Table index
+#endif
+            "movl _dif, %%ebx            \n\t"
+            "cmpl _FullLength, %%ebx     \n\t"
+            "jnb paeth_dend              \n\t"
+
+// preload  "movl row, %%edi             \n\t"
+// preload  "movl prev_row, %%esi        \n\t"
+            // do Paeth decode for remaining bytes
+            "movl %%ebx, %%edx           \n\t"
+// preload  "subl bpp, %%edx             \n\t" // (bpp is preloaded into ecx)
+            "subl %%ecx, %%edx           \n\t" // edx = ebx - bpp
+            "xorl %%ecx, %%ecx           \n\t" // zero ecx before using cl & cx
+
+         "paeth_dlp:                     \n\t"
+            "xorl %%eax, %%eax           \n\t"
+            // pav = p - a = (a + b - c) - a = b - c
+            "movb (%%esi,%%ebx,), %%al   \n\t" // load Prior(x) into al
+            "movb (%%esi,%%edx,), %%cl   \n\t" // load Prior(x-bpp) into cl
+            "subl %%ecx, %%eax           \n\t" // subtract Prior(x-bpp)
+            "movl %%eax, _patemp         \n\t" // Save pav for later use
+            "xorl %%eax, %%eax           \n\t"
+            // pbv = p - b = (a + b - c) - b = a - c
+            "movb (%%edi,%%edx,), %%al   \n\t" // load Raw(x-bpp) into al
+            "subl %%ecx, %%eax           \n\t" // subtract Prior(x-bpp)
+            "movl %%eax, %%ecx           \n\t"
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            "addl _patemp, %%eax         \n\t" // pcv = pav + pbv
+            // pc = abs(pcv)
+            "testl $0x80000000, %%eax    \n\t"
+            "jz paeth_dpca               \n\t"
+            "negl %%eax                  \n\t" // reverse sign of neg values
+
+         "paeth_dpca:                    \n\t"
+            "movl %%eax, _pctemp         \n\t" // save pc for later use
+            // pb = abs(pbv)
+            "testl $0x80000000, %%ecx    \n\t"
+            "jz paeth_dpba               \n\t"
+            "negl %%ecx                  \n\t" // reverse sign of neg values
+
+         "paeth_dpba:                    \n\t"
+            "movl %%ecx, _pbtemp         \n\t" // save pb for later use
+            // pa = abs(pav)
+            "movl _patemp, %%eax         \n\t"
+            "testl $0x80000000, %%eax    \n\t"
+            "jz paeth_dpaa               \n\t"
+            "negl %%eax                  \n\t" // reverse sign of neg values
+
+         "paeth_dpaa:                    \n\t"
+            "movl %%eax, _patemp         \n\t" // save pa for later use
+            // test if pa <= pb
+            "cmpl %%ecx, %%eax           \n\t"
+            "jna paeth_dabb              \n\t"
+            // pa > pb; now test if pb <= pc
+            "cmpl _pctemp, %%ecx         \n\t"
+            "jna paeth_dbbc              \n\t"
+            // pb > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+            "movb (%%esi,%%edx,), %%cl   \n\t" // load Prior(x-bpp) into cl
+            "jmp paeth_dpaeth            \n\t"
+
+         "paeth_dbbc:                    \n\t"
+            // pb <= pc; Raw(x) = Paeth(x) + Prior(x)
+            "movb (%%esi,%%ebx,), %%cl   \n\t" // load Prior(x) into cl
+            "jmp paeth_dpaeth            \n\t"
+
+         "paeth_dabb:                    \n\t"
+            // pa <= pb; now test if pa <= pc
+            "cmpl _pctemp, %%eax         \n\t"
+            "jna paeth_dabc              \n\t"
+            // pa > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+            "movb (%%esi,%%edx,), %%cl   \n\t" // load Prior(x-bpp) into cl
+            "jmp paeth_dpaeth            \n\t"
+
+         "paeth_dabc:                    \n\t"
+            // pa <= pc; Raw(x) = Paeth(x) + Raw(x-bpp)
+            "movb (%%edi,%%edx,), %%cl   \n\t" // load Raw(x-bpp) into cl
+
+         "paeth_dpaeth:                  \n\t"
+            "incl %%ebx                  \n\t"
+            "incl %%edx                  \n\t"
+            // Raw(x) = (Paeth(x) + Paeth_Predictor( a, b, c )) mod 256
+            "addb %%cl, -1(%%edi,%%ebx,) \n\t"
+            "cmpl _FullLength, %%ebx     \n\t"
+            "jb paeth_dlp                \n\t"
+
+         "paeth_dend:                    \n\t"
+#ifdef __PIC__
+            "popl %%ebx                  \n\t" // index to Global Offset Table
+#endif
+
+            : "=c" (dummy_value_c),            // output regs (dummy)
+              "=S" (dummy_value_S),
+              "=D" (dummy_value_D)
+
+            : "0" (bpp),       // ecx          // input regs
+              "1" (prev_row),  // esi
+              "2" (row)        // edi
+
+            : "%eax", "%edx"                   // clobber list
+#ifndef __PIC__
+            , "%ebx"
+#endif
+         );
+      }
+      return;                   // No need to go further with this one
+
+   } // end switch (bpp)
+
+   __asm__ __volatile__ (
+      // MMX acceleration complete; now do clean-up
+      // check if any remaining bytes left to decode
+#ifdef __PIC__
+      "pushl %%ebx                 \n\t" // save index to Global Offset Table
+#endif
+      "movl _MMXLength, %%ebx      \n\t"
+      "cmpl _FullLength, %%ebx     \n\t"
+      "jnb paeth_end               \n\t"
+//pre "movl row, %%edi             \n\t"
+//pre "movl prev_row, %%esi        \n\t"
+      // do Paeth decode for remaining bytes
+      "movl %%ebx, %%edx           \n\t"
+//pre "subl bpp, %%edx             \n\t" // (bpp is preloaded into ecx)
+      "subl %%ecx, %%edx           \n\t" // edx = ebx - bpp
+      "xorl %%ecx, %%ecx           \n\t" // zero ecx before using cl & cx below
+
+   "paeth_lp2:                     \n\t"
+      "xorl %%eax, %%eax           \n\t"
+      // pav = p - a = (a + b - c) - a = b - c
+      "movb (%%esi,%%ebx,), %%al   \n\t" // load Prior(x) into al
+      "movb (%%esi,%%edx,), %%cl   \n\t" // load Prior(x-bpp) into cl
+      "subl %%ecx, %%eax           \n\t" // subtract Prior(x-bpp)
+      "movl %%eax, _patemp         \n\t" // Save pav for later use
+      "xorl %%eax, %%eax           \n\t"
+      // pbv = p - b = (a + b - c) - b = a - c
+      "movb (%%edi,%%edx,), %%al   \n\t" // load Raw(x-bpp) into al
+      "subl %%ecx, %%eax           \n\t" // subtract Prior(x-bpp)
+      "movl %%eax, %%ecx           \n\t"
+      // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+      "addl _patemp, %%eax         \n\t" // pcv = pav + pbv
+      // pc = abs(pcv)
+      "testl $0x80000000, %%eax    \n\t"
+      "jz paeth_pca2               \n\t"
+      "negl %%eax                  \n\t" // reverse sign of neg values
+
+   "paeth_pca2:                    \n\t"
+      "movl %%eax, _pctemp         \n\t" // save pc for later use
+      // pb = abs(pbv)
+      "testl $0x80000000, %%ecx    \n\t"
+      "jz paeth_pba2               \n\t"
+      "negl %%ecx                  \n\t" // reverse sign of neg values
+
+   "paeth_pba2:                    \n\t"
+      "movl %%ecx, _pbtemp         \n\t" // save pb for later use
+      // pa = abs(pav)
+      "movl _patemp, %%eax         \n\t"
+      "testl $0x80000000, %%eax    \n\t"
+      "jz paeth_paa2               \n\t"
+      "negl %%eax                  \n\t" // reverse sign of neg values
+
+   "paeth_paa2:                    \n\t"
+      "movl %%eax, _patemp         \n\t" // save pa for later use
+      // test if pa <= pb
+      "cmpl %%ecx, %%eax           \n\t"
+      "jna paeth_abb2              \n\t"
+      // pa > pb; now test if pb <= pc
+      "cmpl _pctemp, %%ecx         \n\t"
+      "jna paeth_bbc2              \n\t"
+      // pb > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+      "movb (%%esi,%%edx,), %%cl   \n\t" // load Prior(x-bpp) into cl
+      "jmp paeth_paeth2            \n\t"
+
+   "paeth_bbc2:                    \n\t"
+      // pb <= pc; Raw(x) = Paeth(x) + Prior(x)
+      "movb (%%esi,%%ebx,), %%cl   \n\t" // load Prior(x) into cl
+      "jmp paeth_paeth2            \n\t"
+
+   "paeth_abb2:                    \n\t"
+      // pa <= pb; now test if pa <= pc
+      "cmpl _pctemp, %%eax         \n\t"
+      "jna paeth_abc2              \n\t"
+      // pa > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+      "movb (%%esi,%%edx,), %%cl   \n\t" // load Prior(x-bpp) into cl
+      "jmp paeth_paeth2            \n\t"
+
+   "paeth_abc2:                    \n\t"
+      // pa <= pc; Raw(x) = Paeth(x) + Raw(x-bpp)
+      "movb (%%edi,%%edx,), %%cl   \n\t" // load Raw(x-bpp) into cl
+
+   "paeth_paeth2:                  \n\t"
+      "incl %%ebx                  \n\t"
+      "incl %%edx                  \n\t"
+      // Raw(x) = (Paeth(x) + Paeth_Predictor( a, b, c )) mod 256
+      "addb %%cl, -1(%%edi,%%ebx,) \n\t"
+      "cmpl _FullLength, %%ebx     \n\t"
+      "jb paeth_lp2                \n\t"
+
+   "paeth_end:                     \n\t"
+      "EMMS                        \n\t" // end MMX; prep for poss. FP instrs.
+#ifdef __PIC__
+      "popl %%ebx                  \n\t" // restore index to Global Offset Table
+#endif
+
+      : "=c" (dummy_value_c),            // output regs (dummy)
+        "=S" (dummy_value_S),
+        "=D" (dummy_value_D)
+
+      : "0" (bpp),       // ecx          // input regs
+        "1" (prev_row),  // esi
+        "2" (row)        // edi
+
+      : "%eax", "%edx"                   // clobber list (no input regs!)
+#ifndef __PIC__
+      , "%ebx"
+#endif
+   );
+
+} /* end png_read_filter_row_mmx_paeth() */
+#endif
+
+
+
+
+#ifdef PNG_THREAD_UNSAFE_OK
+//===========================================================================//
+//                                                                           //
+//           P N G _ R E A D _ F I L T E R _ R O W _ M M X _ S U B           //
+//                                                                           //
+//===========================================================================//
+
+// Optimized code for PNG Sub filter decoder
+
+static void /* PRIVATE */
+png_read_filter_row_mmx_sub(png_row_infop row_info, png_bytep row)
+{
+   int bpp;
+   int dummy_value_a;
+   int dummy_value_D;
+
+   bpp = (row_info->pixel_depth + 7) >> 3;   // calc number of bytes per pixel
+   _FullLength = row_info->rowbytes - bpp;   // number of bytes to filter
+
+   __asm__ __volatile__ (
+//pre "movl row, %%edi             \n\t"
+      "movl %%edi, %%esi           \n\t" // lp = row
+//pre "movl bpp, %%eax             \n\t"
+      "addl %%eax, %%edi           \n\t" // rp = row + bpp
+//irr "xorl %%eax, %%eax           \n\t"
+      // get # of bytes to alignment
+      "movl %%edi, _dif            \n\t" // take start of row
+      "addl $0xf, _dif             \n\t" // add 7 + 8 to incr past
+                                         //  alignment boundary
+      "xorl %%ecx, %%ecx           \n\t"
+      "andl $0xfffffff8, _dif      \n\t" // mask to alignment boundary
+      "subl %%edi, _dif            \n\t" // subtract from start ==> value
+      "jz sub_go                   \n\t" //  ecx at alignment
+
+   "sub_lp1:                       \n\t" // fix alignment
+      "movb (%%esi,%%ecx,), %%al   \n\t"
+      "addb %%al, (%%edi,%%ecx,)   \n\t"
+      "incl %%ecx                  \n\t"
+      "cmpl _dif, %%ecx            \n\t"
+      "jb sub_lp1                  \n\t"
+
+   "sub_go:                        \n\t"
+      "movl _FullLength, %%eax     \n\t"
+      "movl %%eax, %%edx           \n\t"
+      "subl %%ecx, %%edx           \n\t" // subtract alignment fix
+      "andl $0x00000007, %%edx     \n\t" // calc bytes over mult of 8
+      "subl %%edx, %%eax           \n\t" // drop over bytes from length
+      "movl %%eax, _MMXLength      \n\t"
+
+      : "=a" (dummy_value_a),   // 0      // output regs (dummy)
+        "=D" (dummy_value_D)    // 1
+
+      : "0" (bpp),              // eax    // input regs
+        "1" (row)               // edi
+
+      : "%esi", "%ecx", "%edx"            // clobber list
+
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+      , "%mm0", "%mm1", "%mm2", "%mm3"
+      , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+   );
+
+   // now do the math for the rest of the row
+   switch (bpp)
+   {
+      case 3:
+      {
+         _ActiveMask.use  = 0x0000ffffff000000LL;
+         _ShiftBpp.use = 24;       // == 3 * 8
+         _ShiftRem.use  = 40;      // == 64 - 24
+
+         __asm__ __volatile__ (
+// preload  "movl row, %%edi              \n\t"
+            "movq _ActiveMask, %%mm7       \n\t" // load _ActiveMask for 2nd
+                                                //  active byte group
+            "movl %%edi, %%esi            \n\t" // lp = row
+// preload  "movl bpp, %%eax              \n\t"
+            "addl %%eax, %%edi            \n\t" // rp = row + bpp
+            "movq %%mm7, %%mm6            \n\t"
+            "movl _dif, %%edx             \n\t"
+            "psllq _ShiftBpp, %%mm6       \n\t" // move mask in mm6 to cover
+                                                //  3rd active byte group
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%edx,), %%mm1 \n\t"
+
+         "sub_3lp:                        \n\t" // shift data for adding first
+            "psrlq _ShiftRem, %%mm1       \n\t" //  bpp bytes (no need for mask;
+                                                //  shift clears inactive bytes)
+            // add 1st active group
+            "movq (%%edi,%%edx,), %%mm0   \n\t"
+            "paddb %%mm1, %%mm0           \n\t"
+
+            // add 2nd active group
+            "movq %%mm0, %%mm1            \n\t" // mov updated Raws to mm1
+            "psllq _ShiftBpp, %%mm1       \n\t" // shift data to pos. correctly
+            "pand %%mm7, %%mm1            \n\t" // mask to use 2nd active group
+            "paddb %%mm1, %%mm0           \n\t"
+
+            // add 3rd active group
+            "movq %%mm0, %%mm1            \n\t" // mov updated Raws to mm1
+            "psllq _ShiftBpp, %%mm1       \n\t" // shift data to pos. correctly
+            "pand %%mm6, %%mm1            \n\t" // mask to use 3rd active group
+            "addl $8, %%edx               \n\t"
+            "paddb %%mm1, %%mm0           \n\t"
+
+            "cmpl _MMXLength, %%edx       \n\t"
+            "movq %%mm0, -8(%%edi,%%edx,) \n\t" // write updated Raws to array
+            "movq %%mm0, %%mm1            \n\t" // prep 1st add at top of loop
+            "jb sub_3lp                   \n\t"
+
+            : "=a" (dummy_value_a),   // 0      // output regs (dummy)
+              "=D" (dummy_value_D)    // 1
+
+            : "0" (bpp),              // eax    // input regs
+              "1" (row)               // edi
+
+            : "%edx", "%esi"                    // clobber list
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1", "%mm6", "%mm7"
+#endif
+         );
+      }
+      break;
+
+      case 1:
+      {
+         __asm__ __volatile__ (
+            "movl _dif, %%edx            \n\t"
+// preload  "movl row, %%edi             \n\t"
+            "cmpl _FullLength, %%edx     \n\t"
+            "jnb sub_1end                \n\t"
+            "movl %%edi, %%esi           \n\t" // lp = row
+            "xorl %%eax, %%eax           \n\t"
+// preload  "movl bpp, %%eax             \n\t"
+            "addl %%eax, %%edi           \n\t" // rp = row + bpp
+
+         "sub_1lp:                       \n\t"
+            "movb (%%esi,%%edx,), %%al   \n\t"
+            "addb %%al, (%%edi,%%edx,)   \n\t"
+            "incl %%edx                  \n\t"
+            "cmpl _FullLength, %%edx     \n\t"
+            "jb sub_1lp                  \n\t"
+
+         "sub_1end:                      \n\t"
+
+            : "=a" (dummy_value_a),   // 0      // output regs (dummy)
+              "=D" (dummy_value_D)    // 1
+
+            : "0" (bpp),              // eax    // input regs
+              "1" (row)               // edi
+
+            : "%edx", "%esi"                    // clobber list
+         );
+      }
+      return;
+
+      case 6:
+      case 4:
+      //case 7:   // GRR BOGUS
+      //case 5:   // GRR BOGUS
+      {
+         _ShiftBpp.use = bpp << 3;
+         _ShiftRem.use = 64 - _ShiftBpp.use;
+
+         __asm__ __volatile__ (
+// preload  "movl row, %%edi              \n\t"
+            "movl _dif, %%edx             \n\t"
+            "movl %%edi, %%esi            \n\t" // lp = row
+// preload  "movl bpp, %%eax              \n\t"
+            "addl %%eax, %%edi            \n\t" // rp = row + bpp
+
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%edx,), %%mm1 \n\t"
+
+         "sub_4lp:                        \n\t" // shift data for adding first
+            "psrlq _ShiftRem, %%mm1       \n\t" //  bpp bytes (no need for mask;
+                                                //  shift clears inactive bytes)
+            "movq (%%edi,%%edx,), %%mm0   \n\t"
+            "paddb %%mm1, %%mm0           \n\t"
+
+            // add 2nd active group
+            "movq %%mm0, %%mm1            \n\t" // mov updated Raws to mm1
+            "psllq _ShiftBpp, %%mm1       \n\t" // shift data to pos. correctly
+            "addl $8, %%edx               \n\t"
+            "paddb %%mm1, %%mm0           \n\t"
+
+            "cmpl _MMXLength, %%edx       \n\t"
+            "movq %%mm0, -8(%%edi,%%edx,) \n\t"
+            "movq %%mm0, %%mm1            \n\t" // prep 1st add at top of loop
+            "jb sub_4lp                   \n\t"
+
+            : "=a" (dummy_value_a),   // 0      // output regs (dummy)
+              "=D" (dummy_value_D)    // 1
+
+            : "0" (bpp),              // eax    // input regs
+              "1" (row)               // edi
+
+            : "%edx", "%esi"                    // clobber list
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1"
+#endif
+         );
+      }
+      break;
+
+      case 2:
+      {
+         _ActiveMask.use = 0x00000000ffff0000LL;
+         _ShiftBpp.use = 16;       // == 2 * 8
+         _ShiftRem.use = 48;       // == 64 - 16
+
+         __asm__ __volatile__ (
+            "movq _ActiveMask, %%mm7      \n\t" // load _ActiveMask for 2nd
+                                                //  active byte group
+            "movl _dif, %%edx             \n\t"
+            "movq %%mm7, %%mm6            \n\t"
+// preload  "movl row, %%edi              \n\t"
+            "psllq _ShiftBpp, %%mm6       \n\t" // move mask in mm6 to cover
+                                                //  3rd active byte group
+            "movl %%edi, %%esi            \n\t" // lp = row
+            "movq %%mm6, %%mm5            \n\t"
+// preload  "movl bpp, %%eax              \n\t"
+            "addl %%eax, %%edi            \n\t" // rp = row + bpp
+            "psllq _ShiftBpp, %%mm5       \n\t" // move mask in mm5 to cover
+                                                //  4th active byte group
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%edx,), %%mm1 \n\t"
+
+         "sub_2lp:                        \n\t" // shift data for adding first
+            "psrlq _ShiftRem, %%mm1       \n\t" //  bpp bytes (no need for mask;
+                                                //  shift clears inactive bytes)
+            // add 1st active group
+            "movq (%%edi,%%edx,), %%mm0   \n\t"
+            "paddb %%mm1, %%mm0           \n\t"
+
+            // add 2nd active group
+            "movq %%mm0, %%mm1            \n\t" // mov updated Raws to mm1
+            "psllq _ShiftBpp, %%mm1       \n\t" // shift data to pos. correctly
+            "pand %%mm7, %%mm1            \n\t" // mask to use 2nd active group
+            "paddb %%mm1, %%mm0           \n\t"
+
+            // add 3rd active group
+            "movq %%mm0, %%mm1            \n\t" // mov updated Raws to mm1
+            "psllq _ShiftBpp, %%mm1       \n\t" // shift data to pos. correctly
+            "pand %%mm6, %%mm1            \n\t" // mask to use 3rd active group
+            "paddb %%mm1, %%mm0           \n\t"
+
+            // add 4th active group
+            "movq %%mm0, %%mm1            \n\t" // mov updated Raws to mm1
+            "psllq _ShiftBpp, %%mm1       \n\t" // shift data to pos. correctly
+            "pand %%mm5, %%mm1            \n\t" // mask to use 4th active group
+            "addl $8, %%edx               \n\t"
+            "paddb %%mm1, %%mm0           \n\t"
+            "cmpl _MMXLength, %%edx       \n\t"
+            "movq %%mm0, -8(%%edi,%%edx,) \n\t" // write updated Raws to array
+            "movq %%mm0, %%mm1            \n\t" // prep 1st add at top of loop
+            "jb sub_2lp                   \n\t"
+
+            : "=a" (dummy_value_a),   // 0      // output regs (dummy)
+              "=D" (dummy_value_D)    // 1
+
+            : "0" (bpp),              // eax    // input regs
+              "1" (row)               // edi
+
+            : "%edx", "%esi"                    // clobber list
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1", "%mm5", "%mm6", "%mm7"
+#endif
+         );
+      }
+      break;
+
+      case 8:
+      {
+         __asm__ __volatile__ (
+// preload  "movl row, %%edi              \n\t"
+            "movl _dif, %%edx             \n\t"
+            "movl %%edi, %%esi            \n\t" // lp = row
+// preload  "movl bpp, %%eax              \n\t"
+            "addl %%eax, %%edi            \n\t" // rp = row + bpp
+            "movl _MMXLength, %%ecx       \n\t"
+
+            // prime the pump:  load the first Raw(x-bpp) data set
+            "movq -8(%%edi,%%edx,), %%mm7 \n\t"
+            "andl $0x0000003f, %%ecx      \n\t" // calc bytes over mult of 64
+
+         "sub_8lp:                        \n\t"
+            "movq (%%edi,%%edx,), %%mm0   \n\t" // load Sub(x) for 1st 8 bytes
+            "paddb %%mm7, %%mm0           \n\t"
+            "movq 8(%%edi,%%edx,), %%mm1  \n\t" // load Sub(x) for 2nd 8 bytes
+            "movq %%mm0, (%%edi,%%edx,)   \n\t" // write Raw(x) for 1st 8 bytes
+
+            // Now mm0 will be used as Raw(x-bpp) for the 2nd group of 8 bytes.
+            // This will be repeated for each group of 8 bytes with the 8th
+            // group being used as the Raw(x-bpp) for the 1st group of the
+            // next loop.
+
+            "paddb %%mm0, %%mm1           \n\t"
+            "movq 16(%%edi,%%edx,), %%mm2 \n\t" // load Sub(x) for 3rd 8 bytes
+            "movq %%mm1, 8(%%edi,%%edx,)  \n\t" // write Raw(x) for 2nd 8 bytes
+            "paddb %%mm1, %%mm2           \n\t"
+            "movq 24(%%edi,%%edx,), %%mm3 \n\t" // load Sub(x) for 4th 8 bytes
+            "movq %%mm2, 16(%%edi,%%edx,) \n\t" // write Raw(x) for 3rd 8 bytes
+            "paddb %%mm2, %%mm3           \n\t"
+            "movq 32(%%edi,%%edx,), %%mm4 \n\t" // load Sub(x) for 5th 8 bytes
+            "movq %%mm3, 24(%%edi,%%edx,) \n\t" // write Raw(x) for 4th 8 bytes
+            "paddb %%mm3, %%mm4           \n\t"
+            "movq 40(%%edi,%%edx,), %%mm5 \n\t" // load Sub(x) for 6th 8 bytes
+            "movq %%mm4, 32(%%edi,%%edx,) \n\t" // write Raw(x) for 5th 8 bytes
+            "paddb %%mm4, %%mm5           \n\t"
+            "movq 48(%%edi,%%edx,), %%mm6 \n\t" // load Sub(x) for 7th 8 bytes
+            "movq %%mm5, 40(%%edi,%%edx,) \n\t" // write Raw(x) for 6th 8 bytes
+            "paddb %%mm5, %%mm6           \n\t"
+            "movq 56(%%edi,%%edx,), %%mm7 \n\t" // load Sub(x) for 8th 8 bytes
+            "movq %%mm6, 48(%%edi,%%edx,) \n\t" // write Raw(x) for 7th 8 bytes
+            "addl $64, %%edx              \n\t"
+            "paddb %%mm6, %%mm7           \n\t"
+            "cmpl %%ecx, %%edx            \n\t"
+            "movq %%mm7, -8(%%edi,%%edx,) \n\t" // write Raw(x) for 8th 8 bytes
+            "jb sub_8lp                   \n\t"
+
+            "cmpl _MMXLength, %%edx       \n\t"
+            "jnb sub_8lt8                 \n\t"
+
+         "sub_8lpA:                       \n\t"
+            "movq (%%edi,%%edx,), %%mm0   \n\t"
+            "addl $8, %%edx               \n\t"
+            "paddb %%mm7, %%mm0           \n\t"
+            "cmpl _MMXLength, %%edx       \n\t"
+            "movq %%mm0, -8(%%edi,%%edx,) \n\t" // -8 to offset early addl edx
+            "movq %%mm0, %%mm7            \n\t" // move calculated Raw(x) data
+                                                //  to mm1 to be new Raw(x-bpp)
+                                                //  for next loop
+            "jb sub_8lpA                  \n\t"
+
+         "sub_8lt8:                       \n\t"
+
+            : "=a" (dummy_value_a),   // 0      // output regs (dummy)
+              "=D" (dummy_value_D)    // 1
+
+            : "0" (bpp),              // eax    // input regs
+              "1" (row)               // edi
+
+            : "%ecx", "%edx", "%esi"            // clobber list
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1", "%mm2", "%mm3", "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+         );
+      }
+      break;
+
+      default:                // bpp greater than 8 bytes   GRR BOGUS
+      {
+         __asm__ __volatile__ (
+            "movl _dif, %%edx             \n\t"
+// preload  "movl row, %%edi              \n\t"
+            "movl %%edi, %%esi            \n\t" // lp = row
+// preload  "movl bpp, %%eax              \n\t"
+            "addl %%eax, %%edi            \n\t" // rp = row + bpp
+
+         "sub_Alp:                        \n\t"
+            "movq (%%edi,%%edx,), %%mm0   \n\t"
+            "movq (%%esi,%%edx,), %%mm1   \n\t"
+            "addl $8, %%edx               \n\t"
+            "paddb %%mm1, %%mm0           \n\t"
+            "cmpl _MMXLength, %%edx       \n\t"
+            "movq %%mm0, -8(%%edi,%%edx,) \n\t" // mov does not affect flags;
+                                                //  -8 to offset addl edx
+            "jb sub_Alp                   \n\t"
+
+            : "=a" (dummy_value_a),   // 0      // output regs (dummy)
+              "=D" (dummy_value_D)    // 1
+
+            : "0" (bpp),              // eax    // input regs
+              "1" (row)               // edi
+
+            : "%edx", "%esi"                    // clobber list
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+            , "%mm0", "%mm1"
+#endif
+         );
+      }
+      break;
+
+   } // end switch (bpp)
+
+   __asm__ __volatile__ (
+      "movl _MMXLength, %%edx       \n\t"
+//pre "movl row, %%edi              \n\t"
+      "cmpl _FullLength, %%edx      \n\t"
+      "jnb sub_end                  \n\t"
+
+      "movl %%edi, %%esi            \n\t" // lp = row
+//pre "movl bpp, %%eax              \n\t"
+      "addl %%eax, %%edi            \n\t" // rp = row + bpp
+      "xorl %%eax, %%eax            \n\t"
+
+   "sub_lp2:                        \n\t"
+      "movb (%%esi,%%edx,), %%al    \n\t"
+      "addb %%al, (%%edi,%%edx,)    \n\t"
+      "incl %%edx                   \n\t"
+      "cmpl _FullLength, %%edx      \n\t"
+      "jb sub_lp2                   \n\t"
+
+   "sub_end:                        \n\t"
+      "EMMS                         \n\t" // end MMX instructions
+
+      : "=a" (dummy_value_a),   // 0      // output regs (dummy)
+        "=D" (dummy_value_D)    // 1
+
+      : "0" (bpp),              // eax    // input regs
+        "1" (row)               // edi
+
+      : "%edx", "%esi"                    // clobber list
+   );
+
+} // end of png_read_filter_row_mmx_sub()
+#endif
+
+
+
+
+//===========================================================================//
+//                                                                           //
+//            P N G _ R E A D _ F I L T E R _ R O W _ M M X _ U P            //
+//                                                                           //
+//===========================================================================//
+
+// Optimized code for PNG Up filter decoder
+
+static void /* PRIVATE */
+png_read_filter_row_mmx_up(png_row_infop row_info, png_bytep row,
+                           png_bytep prev_row)
+{
+   png_uint_32 len;
+   int dummy_value_d;   // fix 'forbidden register 3 (dx) was spilled' error
+   int dummy_value_S;
+   int dummy_value_D;
+
+   len = row_info->rowbytes;              // number of bytes to filter
+
+   __asm__ __volatile__ (
+//pre "movl row, %%edi              \n\t"
+      // get # of bytes to alignment
+#ifdef __PIC__
+      "pushl %%ebx                  \n\t"
+#endif
+      "movl %%edi, %%ecx            \n\t"
+      "xorl %%ebx, %%ebx            \n\t"
+      "addl $0x7, %%ecx             \n\t"
+      "xorl %%eax, %%eax            \n\t"
+      "andl $0xfffffff8, %%ecx      \n\t"
+//pre "movl prev_row, %%esi         \n\t"
+      "subl %%edi, %%ecx            \n\t"
+      "jz up_go                     \n\t"
+
+   "up_lp1:                         \n\t" // fix alignment
+      "movb (%%edi,%%ebx,), %%al    \n\t"
+      "addb (%%esi,%%ebx,), %%al    \n\t"
+      "incl %%ebx                   \n\t"
+      "cmpl %%ecx, %%ebx            \n\t"
+      "movb %%al, -1(%%edi,%%ebx,)  \n\t" // mov does not affect flags; -1 to
+      "jb up_lp1                    \n\t" //  offset incl ebx
+
+   "up_go:                          \n\t"
+//pre "movl len, %%edx              \n\t"
+      "movl %%edx, %%ecx            \n\t"
+      "subl %%ebx, %%edx            \n\t" // subtract alignment fix
+      "andl $0x0000003f, %%edx      \n\t" // calc bytes over mult of 64
+      "subl %%edx, %%ecx            \n\t" // drop over bytes from length
+
+      // unrolled loop - use all MMX registers and interleave to reduce
+      // number of branch instructions (loops) and reduce partial stalls
+   "up_loop:                        \n\t"
+      "movq (%%esi,%%ebx,), %%mm1   \n\t"
+      "movq (%%edi,%%ebx,), %%mm0   \n\t"
+      "movq 8(%%esi,%%ebx,), %%mm3  \n\t"
+      "paddb %%mm1, %%mm0           \n\t"
+      "movq 8(%%edi,%%ebx,), %%mm2  \n\t"
+      "movq %%mm0, (%%edi,%%ebx,)   \n\t"
+      "paddb %%mm3, %%mm2           \n\t"
+      "movq 16(%%esi,%%ebx,), %%mm5 \n\t"
+      "movq %%mm2, 8(%%edi,%%ebx,)  \n\t"
+      "movq 16(%%edi,%%ebx,), %%mm4 \n\t"
+      "movq 24(%%esi,%%ebx,), %%mm7 \n\t"
+      "paddb %%mm5, %%mm4           \n\t"
+      "movq 24(%%edi,%%ebx,), %%mm6 \n\t"
+      "movq %%mm4, 16(%%edi,%%ebx,) \n\t"
+      "paddb %%mm7, %%mm6           \n\t"
+      "movq 32(%%esi,%%ebx,), %%mm1 \n\t"
+      "movq %%mm6, 24(%%edi,%%ebx,) \n\t"
+      "movq 32(%%edi,%%ebx,), %%mm0 \n\t"
+      "movq 40(%%esi,%%ebx,), %%mm3 \n\t"
+      "paddb %%mm1, %%mm0           \n\t"
+      "movq 40(%%edi,%%ebx,), %%mm2 \n\t"
+      "movq %%mm0, 32(%%edi,%%ebx,) \n\t"
+      "paddb %%mm3, %%mm2           \n\t"
+      "movq 48(%%esi,%%ebx,), %%mm5 \n\t"
+      "movq %%mm2, 40(%%edi,%%ebx,) \n\t"
+      "movq 48(%%edi,%%ebx,), %%mm4 \n\t"
+      "movq 56(%%esi,%%ebx,), %%mm7 \n\t"
+      "paddb %%mm5, %%mm4           \n\t"
+      "movq 56(%%edi,%%ebx,), %%mm6 \n\t"
+      "movq %%mm4, 48(%%edi,%%ebx,) \n\t"
+      "addl $64, %%ebx              \n\t"
+      "paddb %%mm7, %%mm6           \n\t"
+      "cmpl %%ecx, %%ebx            \n\t"
+      "movq %%mm6, -8(%%edi,%%ebx,) \n\t" // (+56)movq does not affect flags;
+      "jb up_loop                   \n\t" //  -8 to offset addl ebx
+
+      "cmpl $0, %%edx               \n\t" // test for bytes over mult of 64
+      "jz up_end                    \n\t"
+
+      "cmpl $8, %%edx               \n\t" // test for less than 8 bytes
+      "jb up_lt8                    \n\t" //  [added by lcreeve at netins.net]
+
+      "addl %%edx, %%ecx            \n\t"
+      "andl $0x00000007, %%edx      \n\t" // calc bytes over mult of 8
+      "subl %%edx, %%ecx            \n\t" // drop over bytes from length
+      "jz up_lt8                    \n\t"
+
+   "up_lpA:                         \n\t" // use MMX regs to update 8 bytes sim.
+      "movq (%%esi,%%ebx,), %%mm1   \n\t"
+      "movq (%%edi,%%ebx,), %%mm0   \n\t"
+      "addl $8, %%ebx               \n\t"
+      "paddb %%mm1, %%mm0           \n\t"
+      "cmpl %%ecx, %%ebx            \n\t"
+      "movq %%mm0, -8(%%edi,%%ebx,) \n\t" // movq does not affect flags; -8 to
+      "jb up_lpA                    \n\t" //  offset add ebx
+      "cmpl $0, %%edx               \n\t" // test for bytes over mult of 8
+      "jz up_end                    \n\t"
+
+   "up_lt8:                         \n\t"
+      "xorl %%eax, %%eax            \n\t"
+      "addl %%edx, %%ecx            \n\t" // move over byte count into counter
+
+   "up_lp2:                         \n\t" // use x86 regs for remaining bytes
+      "movb (%%edi,%%ebx,), %%al    \n\t"
+      "addb (%%esi,%%ebx,), %%al    \n\t"
+      "incl %%ebx                   \n\t"
+      "cmpl %%ecx, %%ebx            \n\t"
+      "movb %%al, -1(%%edi,%%ebx,)  \n\t" // mov does not affect flags; -1 to
+      "jb up_lp2                    \n\t" //  offset inc ebx
+
+   "up_end:                         \n\t"
+      "EMMS                         \n\t" // conversion of filtered row complete
+#ifdef __PIC__
+      "popl %%ebx                   \n\t"
+#endif
+
+      : "=d" (dummy_value_d),   // 0      // output regs (dummy)
+        "=S" (dummy_value_S),   // 1
+        "=D" (dummy_value_D)    // 2
+
+      : "0" (len),              // edx    // input regs
+        "1" (prev_row),         // esi
+        "2" (row)               // edi
+
+      : "%eax", "%ecx"            // clobber list (no input regs!)
+#ifndef __PIC__
+      , "%ebx"
+#endif
+
+#if 0  /* MMX regs (%mm0, etc.) not supported by gcc 2.7.2.3 or egcs 1.1 */
+      , "%mm0", "%mm1", "%mm2", "%mm3"
+      , "%mm4", "%mm5", "%mm6", "%mm7"
+#endif
+   );
+
+} // end of png_read_filter_row_mmx_up()
+
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+
+
+
+
+/*===========================================================================*/
+/*                                                                           */
+/*                   P N G _ R E A D _ F I L T E R _ R O W                   */
+/*                                                                           */
+/*===========================================================================*/
+
+
+/* Optimized png_read_filter_row routines */
+
+void /* PRIVATE */
+png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep
+   row, png_bytep prev_row, int filter)
+{
+#ifdef PNG_DEBUG
+   char filnm[10];
+#endif
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+/* GRR:  these are superseded by png_ptr->asm_flags: */
+#define UseMMX_sub    1   // GRR:  converted 20000730
+#define UseMMX_up     1   // GRR:  converted 20000729
+#define UseMMX_avg    1   // GRR:  converted 20000828 (+ 16-bit bugfix 20000916)
+#define UseMMX_paeth  1   // GRR:  converted 20000828
+
+   if (_mmx_supported == 2) {
+       /* this should have happened in png_init_mmx_flags() already */
+#if !defined(PNG_1_0_X)
+       png_warning(png_ptr, "asm_flags may not have been initialized");
+#endif
+       png_mmx_support();
+   }
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+
+#ifdef PNG_DEBUG
+   png_debug(1, "in png_read_filter_row (pnggccrd.c)\n");
+   switch (filter)
+   {
+      case 0: sprintf(filnm, "none");
+         break;
+      case 1: sprintf(filnm, "sub-%s",
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_THREAD_UNSAFE_OK)
+#if !defined(PNG_1_0_X)
+        (png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_SUB)? "MMX" : 
+#endif
+#endif
+"x86");
+         break;
+      case 2: sprintf(filnm, "up-%s",
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+#if !defined(PNG_1_0_X)
+        (png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_UP)? "MMX" :
+#endif
+#endif
+ "x86");
+         break;
+      case 3: sprintf(filnm, "avg-%s",
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_THREAD_UNSAFE_OK)
+#if !defined(PNG_1_0_X)
+        (png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_AVG)? "MMX" :
+#endif
+#endif
+ "x86");
+         break;
+      case 4: sprintf(filnm, "Paeth-%s",
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_THREAD_UNSAFE_OK)
+#if !defined(PNG_1_0_X)
+        (png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_PAETH)? "MMX":
+#endif
+#endif
+"x86");
+         break;
+      default: sprintf(filnm, "unknw");
+         break;
+   }
+   png_debug2(0, "row_number=%5ld, %5s, ", png_ptr->row_number, filnm);
+   png_debug1(0, "row=0x%08lx, ", (unsigned long)row);
+   png_debug2(0, "pixdepth=%2d, bytes=%d, ", (int)row_info->pixel_depth,
+      (int)((row_info->pixel_depth + 7) >> 3));
+   png_debug1(0,"rowbytes=%8ld\n", row_info->rowbytes);
+#endif /* PNG_DEBUG */
+
+   switch (filter)
+   {
+      case PNG_FILTER_VALUE_NONE:
+         break;
+
+      case PNG_FILTER_VALUE_SUB:
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_THREAD_UNSAFE_OK)
+#if !defined(PNG_1_0_X)
+         if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_SUB) &&
+             (row_info->pixel_depth >= png_ptr->mmx_bitdepth_threshold) &&
+             (row_info->rowbytes >= png_ptr->mmx_rowbytes_threshold))
+#else
+         if (_mmx_supported)
+#endif
+         {
+            png_read_filter_row_mmx_sub(row_info, row);
+         }
+         else
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+         {
+            png_uint_32 i;
+            png_uint_32 istop = row_info->rowbytes;
+            png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+            png_bytep rp = row + bpp;
+            png_bytep lp = row;
+
+            for (i = bpp; i < istop; i++)
+            {
+               *rp = (png_byte)(((int)(*rp) + (int)(*lp++)) & 0xff);
+               rp++;
+            }
+         }  /* end !UseMMX_sub */
+         break;
+
+      case PNG_FILTER_VALUE_UP:
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+#if !defined(PNG_1_0_X)
+         if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_UP) &&
+             (row_info->pixel_depth >= png_ptr->mmx_bitdepth_threshold) &&
+             (row_info->rowbytes >= png_ptr->mmx_rowbytes_threshold))
+#else
+         if (_mmx_supported)
+#endif
+         {
+            png_read_filter_row_mmx_up(row_info, row, prev_row);
+         }
+          else
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+         {
+            png_uint_32 i;
+            png_uint_32 istop = row_info->rowbytes;
+            png_bytep rp = row;
+            png_bytep pp = prev_row;
+
+            for (i = 0; i < istop; ++i)
+            {
+               *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
+               rp++;
+            }
+         }  /* end !UseMMX_up */
+         break;
+
+      case PNG_FILTER_VALUE_AVG:
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_THREAD_UNSAFE_OK)
+#if !defined(PNG_1_0_X)
+         if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_AVG) &&
+             (row_info->pixel_depth >= png_ptr->mmx_bitdepth_threshold) &&
+             (row_info->rowbytes >= png_ptr->mmx_rowbytes_threshold))
+#else
+         if (_mmx_supported)
+#endif
+         {
+            png_read_filter_row_mmx_avg(row_info, row, prev_row);
+         }
+         else
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+         {
+            png_uint_32 i;
+            png_bytep rp = row;
+            png_bytep pp = prev_row;
+            png_bytep lp = row;
+            png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+            png_uint_32 istop = row_info->rowbytes - bpp;
+
+            for (i = 0; i < bpp; i++)
+            {
+               *rp = (png_byte)(((int)(*rp) +
+                  ((int)(*pp++) >> 1)) & 0xff);
+               rp++;
+            }
+
+            for (i = 0; i < istop; i++)
+            {
+               *rp = (png_byte)(((int)(*rp) +
+                  ((int)(*pp++ + *lp++) >> 1)) & 0xff);
+               rp++;
+            }
+         }  /* end !UseMMX_avg */
+         break;
+
+      case PNG_FILTER_VALUE_PAETH:
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_THREAD_UNSAFE_OK)
+#if !defined(PNG_1_0_X)
+         if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_PAETH) &&
+             (row_info->pixel_depth >= png_ptr->mmx_bitdepth_threshold) &&
+             (row_info->rowbytes >= png_ptr->mmx_rowbytes_threshold))
+#else
+         if (_mmx_supported)
+#endif
+         {
+            png_read_filter_row_mmx_paeth(row_info, row, prev_row);
+         }
+         else
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+         {
+            png_uint_32 i;
+            png_bytep rp = row;
+            png_bytep pp = prev_row;
+            png_bytep lp = row;
+            png_bytep cp = prev_row;
+            png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+            png_uint_32 istop = row_info->rowbytes - bpp;
+
+            for (i = 0; i < bpp; i++)
+            {
+               *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
+               rp++;
+            }
+
+            for (i = 0; i < istop; i++)   /* use leftover rp,pp */
+            {
+               int a, b, c, pa, pb, pc, p;
+
+               a = *lp++;
+               b = *pp++;
+               c = *cp++;
+
+               p = b - c;
+               pc = a - c;
+
+#ifdef PNG_USE_ABS
+               pa = abs(p);
+               pb = abs(pc);
+               pc = abs(p + pc);
+#else
+               pa = p < 0 ? -p : p;
+               pb = pc < 0 ? -pc : pc;
+               pc = (p + pc) < 0 ? -(p + pc) : p + pc;
+#endif
+
+               /*
+                  if (pa <= pb && pa <= pc)
+                     p = a;
+                  else if (pb <= pc)
+                     p = b;
+                  else
+                     p = c;
+                */
+
+               p = (pa <= pb && pa <= pc) ? a : (pb <= pc) ? b : c;
+
+               *rp = (png_byte)(((int)(*rp) + p) & 0xff);
+               rp++;
+            }
+         }  /* end !UseMMX_paeth */
+         break;
+
+      default:
+         png_warning(png_ptr, "Ignoring bad row-filter type");
+         *row=0;
+         break;
+   }
+}
+
+#endif /* PNG_HAVE_ASSEMBLER_READ_FILTER_ROW */
+
+
+/*===========================================================================*/
+/*                                                                           */
+/*                      P N G _ M M X _ S U P P O R T                        */
+/*                                                                           */
+/*===========================================================================*/
+
+/* GRR NOTES:  (1) the following code assumes 386 or better (pushfl/popfl)
+ *             (2) all instructions compile with gcc 2.7.2.3 and later
+ *             (3) the function is moved down here to prevent gcc from
+ *                  inlining it in multiple places and then barfing be-
+ *                  cause the ".NOT_SUPPORTED" label is multiply defined
+ *             [is there a way to signal that a *single* function should
+ *              not be inlined?  is there a way to modify the label for
+ *              each inlined instance, e.g., by appending _1, _2, etc.?
+ *              maybe if don't use leading "." in label name? (nope...sigh)]
+ */
+
+int PNGAPI
+png_mmx_support(void)
+{
+#if defined(PNG_MMX_CODE_SUPPORTED)
+    __asm__ __volatile__ (
+        "pushl %%ebx          \n\t"  // ebx gets clobbered by CPUID instruction
+        "pushl %%ecx          \n\t"  // so does ecx...
+        "pushl %%edx          \n\t"  // ...and edx (but ecx & edx safe on Linux)
+//      ".byte  0x66          \n\t"  // convert 16-bit pushf to 32-bit pushfd
+//      "pushf                \n\t"  // 16-bit pushf
+        "pushfl               \n\t"  // save Eflag to stack
+        "popl %%eax           \n\t"  // get Eflag from stack into eax
+        "movl %%eax, %%ecx    \n\t"  // make another copy of Eflag in ecx
+        "xorl $0x200000, %%eax \n\t" // toggle ID bit in Eflag (i.e., bit 21)
+        "pushl %%eax          \n\t"  // save modified Eflag back to stack
+//      ".byte  0x66          \n\t"  // convert 16-bit popf to 32-bit popfd
+//      "popf                 \n\t"  // 16-bit popf
+        "popfl                \n\t"  // restore modified value to Eflag reg
+        "pushfl               \n\t"  // save Eflag to stack
+        "popl %%eax           \n\t"  // get Eflag from stack
+        "pushl %%ecx          \n\t"  // save original Eflag to stack
+        "popfl                \n\t"  // restore original Eflag
+        "xorl %%ecx, %%eax    \n\t"  // compare new Eflag with original Eflag
+        "jz 0f                \n\t"  // if same, CPUID instr. is not supported
+
+        "xorl %%eax, %%eax    \n\t"  // set eax to zero
+//      ".byte  0x0f, 0xa2    \n\t"  // CPUID instruction (two-byte opcode)
+        "cpuid                \n\t"  // get the CPU identification info
+        "cmpl $1, %%eax       \n\t"  // make sure eax return non-zero value
+        "jl 0f                \n\t"  // if eax is zero, MMX is not supported
+
+        "xorl %%eax, %%eax    \n\t"  // set eax to zero and...
+        "incl %%eax           \n\t"  // ...increment eax to 1.  This pair is
+                                     // faster than the instruction "mov eax, 1"
+        "cpuid                \n\t"  // get the CPU identification info again
+        "andl $0x800000, %%edx \n\t" // mask out all bits but MMX bit (23)
+        "cmpl $0, %%edx       \n\t"  // 0 = MMX not supported
+        "jz 0f                \n\t"  // non-zero = yes, MMX IS supported
+
+        "movl $1, %%eax       \n\t"  // set return value to 1
+        "jmp  1f              \n\t"  // DONE:  have MMX support
+
+    "0:                       \n\t"  // .NOT_SUPPORTED: target label for jump instructions
+        "movl $0, %%eax       \n\t"  // set return value to 0
+    "1:                       \n\t"  // .RETURN: target label for jump instructions
+        "movl %%eax, _mmx_supported \n\t" // save in global static variable, too
+        "popl %%edx           \n\t"  // restore edx
+        "popl %%ecx           \n\t"  // restore ecx
+        "popl %%ebx           \n\t"  // restore ebx
+
+//      "ret                  \n\t"  // DONE:  no MMX support
+                                     // (fall through to standard C "ret")
+
+        :                            // output list (none)
+
+        :                            // any variables used on input (none)
+
+        : "%eax"                     // clobber list
+//      , "%ebx", "%ecx", "%edx"     // GRR:  we handle these manually
+//      , "memory"   // if write to a variable gcc thought was in a reg
+//      , "cc"       // "condition codes" (flag bits)
+    );
+#else     
+    _mmx_supported = 0;
+#endif /* PNG_MMX_CODE_SUPPORTED */
+
+    return _mmx_supported;
+}
+
+
+#endif /* PNG_USE_PNGGCCRD */
diff --git a/gs/libpng/pngget.c b/gs/libpng/pngget.c
new file mode 100644
index 000000000..8eefa7779
--- /dev/null
+++ b/gs/libpng/pngget.c
@@ -0,0 +1,934 @@
+
+/* pngget.c - retrieval of values from info struct
+ *
+ * libpng 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+png_uint_32 PNGAPI
+png_get_valid(png_structp png_ptr, png_infop info_ptr, png_uint_32 flag)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+      return(info_ptr->valid & flag);
+   else
+      return(0);
+}
+
+png_uint_32 PNGAPI
+png_get_rowbytes(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+      return(info_ptr->rowbytes);
+   else
+      return(0);
+}
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+png_bytepp PNGAPI
+png_get_rows(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+      return(info_ptr->row_pointers);
+   else
+      return(0);
+}
+#endif
+
+#ifdef PNG_EASY_ACCESS_SUPPORTED
+/* easy access to info, added in libpng-0.99 */
+png_uint_32 PNGAPI
+png_get_image_width(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->width;
+   }
+   return (0);
+}
+
+png_uint_32 PNGAPI
+png_get_image_height(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->height;
+   }
+   return (0);
+}
+
+png_byte PNGAPI
+png_get_bit_depth(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->bit_depth;
+   }
+   return (0);
+}
+
+png_byte PNGAPI
+png_get_color_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->color_type;
+   }
+   return (0);
+}
+
+png_byte PNGAPI
+png_get_filter_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->filter_type;
+   }
+   return (0);
+}
+
+png_byte PNGAPI
+png_get_interlace_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->interlace_type;
+   }
+   return (0);
+}
+
+png_byte PNGAPI
+png_get_compression_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->compression_type;
+   }
+   return (0);
+}
+
+png_uint_32 PNGAPI
+png_get_x_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_pHYs_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_pHYs)
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_x_pixels_per_meter");
+      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
+          return (0);
+      else return (info_ptr->x_pixels_per_unit);
+   }
+#else
+   return (0);
+#endif
+   return (0);
+}
+
+png_uint_32 PNGAPI
+png_get_y_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_pHYs_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_pHYs)
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_y_pixels_per_meter");
+      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
+          return (0);
+      else return (info_ptr->y_pixels_per_unit);
+   }
+#else
+   return (0);
+#endif
+   return (0);
+}
+
+png_uint_32 PNGAPI
+png_get_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_pHYs_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_pHYs)
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_pixels_per_meter");
+      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER ||
+         info_ptr->x_pixels_per_unit != info_ptr->y_pixels_per_unit)
+          return (0);
+      else return (info_ptr->x_pixels_per_unit);
+   }
+#else
+   return (0);
+#endif
+   return (0);
+}
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+float PNGAPI
+png_get_pixel_aspect_ratio(png_structp png_ptr, png_infop info_ptr)
+   {
+   if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_pHYs_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_pHYs)
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_aspect_ratio");
+      if (info_ptr->x_pixels_per_unit == 0)
+         return ((float)0.0);
+      else
+         return ((float)((float)info_ptr->y_pixels_per_unit
+            /(float)info_ptr->x_pixels_per_unit));
+   }
+#else
+   return (0.0);
+#endif
+   return ((float)0.0);
+}
+#endif
+
+png_int_32 PNGAPI
+png_get_x_offset_microns(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_oFFs_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_oFFs)
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
+          return (0);
+      else return (info_ptr->x_offset);
+   }
+#else
+   return (0);
+#endif
+   return (0);
+}
+
+png_int_32 PNGAPI
+png_get_y_offset_microns(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_oFFs_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_oFFs)
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
+          return (0);
+      else return (info_ptr->y_offset);
+   }
+#else
+   return (0);
+#endif
+   return (0);
+}
+
+png_int_32 PNGAPI
+png_get_x_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_oFFs_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_oFFs)
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
+          return (0);
+      else return (info_ptr->x_offset);
+   }
+#else
+   return (0);
+#endif
+   return (0);
+}
+
+png_int_32 PNGAPI
+png_get_y_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+#if defined(PNG_oFFs_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_oFFs)
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
+          return (0);
+      else return (info_ptr->y_offset);
+   }
+#else
+   return (0);
+#endif
+   return (0);
+}
+
+#if defined(PNG_INCH_CONVERSIONS) && defined(PNG_FLOATING_POINT_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((png_uint_32)((float)png_get_pixels_per_meter(png_ptr, info_ptr)
+     *.0254 +.5));
+}
+
+png_uint_32 PNGAPI
+png_get_x_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((png_uint_32)((float)png_get_x_pixels_per_meter(png_ptr, info_ptr)
+     *.0254 +.5));
+}
+
+png_uint_32 PNGAPI
+png_get_y_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((png_uint_32)((float)png_get_y_pixels_per_meter(png_ptr, info_ptr)
+     *.0254 +.5));
+}
+
+float PNGAPI
+png_get_x_offset_inches(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((float)png_get_x_offset_microns(png_ptr, info_ptr)
+     *.00003937);
+}
+
+float PNGAPI
+png_get_y_offset_inches(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((float)png_get_y_offset_microns(png_ptr, info_ptr)
+     *.00003937);
+}
+
+#if defined(PNG_pHYs_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_pHYs_dpi(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
+{
+   png_uint_32 retval = 0;
+
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "pHYs");
+      if (res_x != NULL)
+      {
+         *res_x = info_ptr->x_pixels_per_unit;
+         retval |= PNG_INFO_pHYs;
+      }
+      if (res_y != NULL)
+      {
+         *res_y = info_ptr->y_pixels_per_unit;
+         retval |= PNG_INFO_pHYs;
+      }
+      if (unit_type != NULL)
+      {
+         *unit_type = (int)info_ptr->phys_unit_type;
+         retval |= PNG_INFO_pHYs;
+         if(*unit_type == 1)
+         {
+            if (res_x != NULL) *res_x = (png_uint_32)(*res_x * .0254 + .50);
+            if (res_y != NULL) *res_y = (png_uint_32)(*res_y * .0254 + .50);
+         }
+      }
+   }
+   return (retval);
+}
+#endif /* PNG_pHYs_SUPPORTED */
+#endif  /* PNG_INCH_CONVERSIONS && PNG_FLOATING_POINT_SUPPORTED */
+
+/* png_get_channels really belongs in here, too, but it's been around longer */
+
+#endif  /* PNG_EASY_ACCESS_SUPPORTED */
+
+png_byte PNGAPI
+png_get_channels(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+      return(info_ptr->channels);
+   else
+      return (0);
+}
+
+png_bytep PNGAPI
+png_get_signature(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+      return(info_ptr->signature);
+   else
+      return (NULL);
+}
+
+#if defined(PNG_bKGD_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_bKGD(png_structp png_ptr, png_infop info_ptr,
+   png_color_16p *background)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)
+      && background != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "bKGD");
+      *background = &(info_ptr->background);
+      return (PNG_INFO_bKGD);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_cHRM(png_structp png_ptr, png_infop info_ptr,
+   double *white_x, double *white_y, double *red_x, double *red_y,
+   double *green_x, double *green_y, double *blue_x, double *blue_y)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
+   {
+      png_debug1(1, "in %s retrieval function\n", "cHRM");
+      if (white_x != NULL)
+         *white_x = (double)info_ptr->x_white;
+      if (white_y != NULL)
+         *white_y = (double)info_ptr->y_white;
+      if (red_x != NULL)
+         *red_x = (double)info_ptr->x_red;
+      if (red_y != NULL)
+         *red_y = (double)info_ptr->y_red;
+      if (green_x != NULL)
+         *green_x = (double)info_ptr->x_green;
+      if (green_y != NULL)
+         *green_y = (double)info_ptr->y_green;
+      if (blue_x != NULL)
+         *blue_x = (double)info_ptr->x_blue;
+      if (blue_y != NULL)
+         *blue_y = (double)info_ptr->y_blue;
+      return (PNG_INFO_cHRM);
+   }
+   return (0);
+}
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,
+   png_fixed_point *white_x, png_fixed_point *white_y, png_fixed_point *red_x,
+   png_fixed_point *red_y, png_fixed_point *green_x, png_fixed_point *green_y,
+   png_fixed_point *blue_x, png_fixed_point *blue_y)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
+   {
+      png_debug1(1, "in %s retrieval function\n", "cHRM");
+      if (white_x != NULL)
+         *white_x = info_ptr->int_x_white;
+      if (white_y != NULL)
+         *white_y = info_ptr->int_y_white;
+      if (red_x != NULL)
+         *red_x = info_ptr->int_x_red;
+      if (red_y != NULL)
+         *red_y = info_ptr->int_y_red;
+      if (green_x != NULL)
+         *green_x = info_ptr->int_x_green;
+      if (green_y != NULL)
+         *green_y = info_ptr->int_y_green;
+      if (blue_x != NULL)
+         *blue_x = info_ptr->int_x_blue;
+      if (blue_y != NULL)
+         *blue_y = info_ptr->int_y_blue;
+      return (PNG_INFO_cHRM);
+   }
+   return (0);
+}
+#endif
+#endif
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
+      && file_gamma != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "gAMA");
+      *file_gamma = (double)info_ptr->gamma;
+      return (PNG_INFO_gAMA);
+   }
+   return (0);
+}
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_gAMA_fixed(png_structp png_ptr, png_infop info_ptr,
+    png_fixed_point *int_file_gamma)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
+      && int_file_gamma != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "gAMA");
+      *int_file_gamma = info_ptr->int_gamma;
+      return (PNG_INFO_gAMA);
+   }
+   return (0);
+}
+#endif
+#endif
+
+#if defined(PNG_sRGB_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_sRGB(png_structp png_ptr, png_infop info_ptr, int *file_srgb_intent)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)
+      && file_srgb_intent != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "sRGB");
+      *file_srgb_intent = (int)info_ptr->srgb_intent;
+      return (PNG_INFO_sRGB);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_iCCP_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_iCCP(png_structp png_ptr, png_infop info_ptr,
+             png_charpp name, int *compression_type,
+             png_charpp profile, png_uint_32 *proflen)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP)
+      && name != NULL && profile != NULL && proflen != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "iCCP");
+      *name = info_ptr->iccp_name;
+      *profile = info_ptr->iccp_profile;
+      /* compression_type is a dummy so the API won't have to change
+         if we introduce multiple compression types later. */
+      *proflen = (int)info_ptr->iccp_proflen;
+      *compression_type = (int)info_ptr->iccp_compression;
+      return (PNG_INFO_iCCP);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_sPLT(png_structp png_ptr, png_infop info_ptr,
+             png_sPLT_tpp spalettes)
+{
+   if (png_ptr != NULL && info_ptr != NULL && spalettes != NULL)
+     *spalettes = info_ptr->splt_palettes;
+   return ((png_uint_32)info_ptr->splt_palettes_num);
+}
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p *hist)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)
+      && hist != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "hIST");
+      *hist = info_ptr->hist;
+      return (PNG_INFO_hIST);
+   }
+   return (0);
+}
+#endif
+
+png_uint_32 PNGAPI
+png_get_IHDR(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 *width, png_uint_32 *height, int *bit_depth,
+   int *color_type, int *interlace_type, int *compression_type,
+   int *filter_type)
+
+{
+   if (png_ptr != NULL && info_ptr != NULL && width != NULL && height != NULL &&
+      bit_depth != NULL && color_type != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "IHDR");
+      *width = info_ptr->width;
+      *height = info_ptr->height;
+      *bit_depth = info_ptr->bit_depth;
+      if (info_ptr->bit_depth < 1 || info_ptr->bit_depth > 16)
+        png_error(png_ptr, "Invalid bit depth");
+      *color_type = info_ptr->color_type;
+      if (info_ptr->color_type > 6)
+        png_error(png_ptr, "Invalid color type");
+      if (compression_type != NULL)
+         *compression_type = info_ptr->compression_type;
+      if (filter_type != NULL)
+         *filter_type = info_ptr->filter_type;
+      if (interlace_type != NULL)
+         *interlace_type = info_ptr->interlace_type;
+
+      /* check for potential overflow of rowbytes */
+      if (*width == 0 || *width > PNG_UINT_31_MAX)
+        png_error(png_ptr, "Invalid image width");
+      if (*height == 0 || *height > PNG_UINT_31_MAX)
+        png_error(png_ptr, "Invalid image height");
+      if (info_ptr->width > (PNG_UINT_32_MAX
+                 >> 3)      /* 8-byte RGBA pixels */
+                 - 64       /* bigrowbuf hack */
+                 - 1        /* filter byte */
+                 - 7*8      /* rounding of width to multiple of 8 pixels */
+                 - 8)       /* extra max_pixel_depth pad */
+      {
+         png_warning(png_ptr,
+            "Width too large for libpng to process image data.");
+      }
+      return (1);
+   }
+   return (0);
+}
+
+#if defined(PNG_oFFs_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_oFFs(png_structp png_ptr, png_infop info_ptr,
+   png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)
+      && offset_x != NULL && offset_y != NULL && unit_type != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "oFFs");
+      *offset_x = info_ptr->x_offset;
+      *offset_y = info_ptr->y_offset;
+      *unit_type = (int)info_ptr->offset_unit_type;
+      return (PNG_INFO_oFFs);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_pCAL(png_structp png_ptr, png_infop info_ptr,
+   png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, int *nparams,
+   png_charp *units, png_charpp *params)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL)
+      && purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
+      nparams != NULL && units != NULL && params != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "pCAL");
+      *purpose = info_ptr->pcal_purpose;
+      *X0 = info_ptr->pcal_X0;
+      *X1 = info_ptr->pcal_X1;
+      *type = (int)info_ptr->pcal_type;
+      *nparams = (int)info_ptr->pcal_nparams;
+      *units = info_ptr->pcal_units;
+      *params = info_ptr->pcal_params;
+      return (PNG_INFO_pCAL);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_sCAL_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_sCAL(png_structp png_ptr, png_infop info_ptr,
+             int *unit, double *width, double *height)
+{
+    if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_sCAL))
+    {
+        *unit = info_ptr->scal_unit;
+        *width = info_ptr->scal_pixel_width;
+        *height = info_ptr->scal_pixel_height;
+        return (PNG_INFO_sCAL);
+    }
+    return(0);
+}
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_sCAL_s(png_structp png_ptr, png_infop info_ptr,
+             int *unit, png_charpp width, png_charpp height)
+{
+    if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_sCAL))
+    {
+        *unit = info_ptr->scal_unit;
+        *width = info_ptr->scal_s_width;
+        *height = info_ptr->scal_s_height;
+        return (PNG_INFO_sCAL);
+    }
+    return(0);
+}
+#endif
+#endif
+#endif
+
+#if defined(PNG_pHYs_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_pHYs(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
+{
+   png_uint_32 retval = 0;
+
+   if (png_ptr != NULL && info_ptr != NULL &&
+      (info_ptr->valid & PNG_INFO_pHYs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "pHYs");
+      if (res_x != NULL)
+      {
+         *res_x = info_ptr->x_pixels_per_unit;
+         retval |= PNG_INFO_pHYs;
+      }
+      if (res_y != NULL)
+      {
+         *res_y = info_ptr->y_pixels_per_unit;
+         retval |= PNG_INFO_pHYs;
+      }
+      if (unit_type != NULL)
+      {
+         *unit_type = (int)info_ptr->phys_unit_type;
+         retval |= PNG_INFO_pHYs;
+      }
+   }
+   return (retval);
+}
+#endif
+
+png_uint_32 PNGAPI
+png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette,
+   int *num_palette)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_PLTE)
+       && palette != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "PLTE");
+      *palette = info_ptr->palette;
+      *num_palette = info_ptr->num_palette;
+      png_debug1(3, "num_palette = %d\n", *num_palette);
+      return (PNG_INFO_PLTE);
+   }
+   return (0);
+}
+
+#if defined(PNG_sBIT_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_sBIT(png_structp png_ptr, png_infop info_ptr, png_color_8p *sig_bit)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT)
+      && sig_bit != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "sBIT");
+      *sig_bit = &(info_ptr->sig_bit);
+      return (PNG_INFO_sBIT);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_TEXT_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_text(png_structp png_ptr, png_infop info_ptr, png_textp *text_ptr,
+   int *num_text)
+{
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->num_text > 0)
+   {
+      png_debug1(1, "in %s retrieval function\n",
+         (png_ptr->chunk_name[0] == '\0' ? "text"
+             : (png_const_charp)png_ptr->chunk_name));
+      if (text_ptr != NULL)
+         *text_ptr = info_ptr->text;
+      if (num_text != NULL)
+         *num_text = info_ptr->num_text;
+      return ((png_uint_32)info_ptr->num_text);
+   }
+   if (num_text != NULL)
+     *num_text = 0;
+   return(0);
+}
+#endif
+
+#if defined(PNG_tIME_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_tIME(png_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME)
+       && mod_time != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "tIME");
+      *mod_time = &(info_ptr->mod_time);
+      return (PNG_INFO_tIME);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_tRNS(png_structp png_ptr, png_infop info_ptr,
+   png_bytep *trans, int *num_trans, png_color_16p *trans_values)
+{
+   png_uint_32 retval = 0;
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
+   {
+      png_debug1(1, "in %s retrieval function\n", "tRNS");
+      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      {
+          if (trans != NULL)
+          {
+             *trans = info_ptr->trans;
+             retval |= PNG_INFO_tRNS;
+          }
+          if (trans_values != NULL)
+             *trans_values = &(info_ptr->trans_values);
+      }
+      else /* if (info_ptr->color_type != PNG_COLOR_TYPE_PALETTE) */
+      {
+          if (trans_values != NULL)
+          {
+             *trans_values = &(info_ptr->trans_values);
+             retval |= PNG_INFO_tRNS;
+          }
+          if(trans != NULL)
+             *trans = NULL;
+      }
+      if(num_trans != NULL)
+      {
+         *num_trans = info_ptr->num_trans;
+         retval |= PNG_INFO_tRNS;
+      }
+   }
+   return (retval);
+}
+#endif
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+png_uint_32 PNGAPI
+png_get_unknown_chunks(png_structp png_ptr, png_infop info_ptr,
+             png_unknown_chunkpp unknowns)
+{
+   if (png_ptr != NULL && info_ptr != NULL && unknowns != NULL)
+     *unknowns = info_ptr->unknown_chunks;
+   return ((png_uint_32)info_ptr->unknown_chunks_num);
+}
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+png_byte PNGAPI
+png_get_rgb_to_gray_status (png_structp png_ptr)
+{
+   return (png_byte)(png_ptr? png_ptr->rgb_to_gray_status : 0);
+}
+#endif
+
+#if defined(PNG_USER_CHUNKS_SUPPORTED)
+png_voidp PNGAPI
+png_get_user_chunk_ptr(png_structp png_ptr)
+{
+   return (png_ptr? png_ptr->user_chunk_ptr : NULL);
+}
+#endif
+
+#ifdef PNG_WRITE_SUPPORTED
+png_uint_32 PNGAPI
+png_get_compression_buffer_size(png_structp png_ptr)
+{
+   return (png_uint_32)(png_ptr? png_ptr->zbuf_size : 0L);
+}
+#endif
+
+#ifndef PNG_1_0_X
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+/* this function was added to libpng 1.2.0 and should exist by default */
+png_uint_32 PNGAPI
+png_get_asm_flags (png_structp png_ptr)
+{
+    return (png_uint_32)(png_ptr? png_ptr->asm_flags : 0L);
+}
+
+/* this function was added to libpng 1.2.0 and should exist by default */
+png_uint_32 PNGAPI
+png_get_asm_flagmask (int flag_select)
+{
+    png_uint_32 settable_asm_flags = 0;
+
+    if (flag_select & PNG_SELECT_READ)
+        settable_asm_flags |=
+          PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  |
+          PNG_ASM_FLAG_MMX_READ_INTERLACE    |
+          PNG_ASM_FLAG_MMX_READ_FILTER_SUB   |
+          PNG_ASM_FLAG_MMX_READ_FILTER_UP    |
+          PNG_ASM_FLAG_MMX_READ_FILTER_AVG   |
+          PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ;
+          /* no non-MMX flags yet */
+
+#if 0
+    /* GRR:  no write-flags yet, either, but someday... */
+    if (flag_select & PNG_SELECT_WRITE)
+        settable_asm_flags |=
+          PNG_ASM_FLAG_MMX_WRITE_ [whatever] ;
+#endif /* 0 */
+
+    return settable_asm_flags;  /* _theoretically_ settable capabilities only */
+}
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
+
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
+    /* GRR:  could add this:   && defined(PNG_MMX_CODE_SUPPORTED) */
+/* this function was added to libpng 1.2.0 */
+png_uint_32 PNGAPI
+png_get_mmx_flagmask (int flag_select, int *compilerID)
+{
+    png_uint_32 settable_mmx_flags = 0;
+
+    if (flag_select & PNG_SELECT_READ)
+        settable_mmx_flags |=
+          PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  |
+          PNG_ASM_FLAG_MMX_READ_INTERLACE    |
+          PNG_ASM_FLAG_MMX_READ_FILTER_SUB   |
+          PNG_ASM_FLAG_MMX_READ_FILTER_UP    |
+          PNG_ASM_FLAG_MMX_READ_FILTER_AVG   |
+          PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ;
+#if 0
+    /* GRR:  no MMX write support yet, but someday... */
+    if (flag_select & PNG_SELECT_WRITE)
+        settable_mmx_flags |=
+          PNG_ASM_FLAG_MMX_WRITE_ [whatever] ;
+#endif /* 0 */
+
+    if (compilerID != NULL) {
+#ifdef PNG_USE_PNGVCRD
+        *compilerID = 1;    /* MSVC */
+#else
+#ifdef PNG_USE_PNGGCCRD
+        *compilerID = 2;    /* gcc/gas */
+#else
+        *compilerID = -1;   /* unknown (i.e., no asm/MMX code compiled) */
+#endif
+#endif
+    }
+
+    return settable_mmx_flags;  /* _theoretically_ settable capabilities only */
+}
+
+/* this function was added to libpng 1.2.0 */
+png_byte PNGAPI
+png_get_mmx_bitdepth_threshold (png_structp png_ptr)
+{
+    return (png_byte)(png_ptr? png_ptr->mmx_bitdepth_threshold : 0);
+}
+
+/* this function was added to libpng 1.2.0 */
+png_uint_32 PNGAPI
+png_get_mmx_rowbytes_threshold (png_structp png_ptr)
+{
+    return (png_uint_32)(png_ptr? png_ptr->mmx_rowbytes_threshold : 0L);
+}
+#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
+
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+/* these functions were added to libpng 1.2.6 */
+png_uint_32 PNGAPI
+png_get_user_width_max (png_structp png_ptr)
+{
+    return (png_ptr? png_ptr->user_width_max : 0);
+}
+png_uint_32 PNGAPI
+png_get_user_height_max (png_structp png_ptr)
+{
+    return (png_ptr? png_ptr->user_height_max : 0);
+}
+#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
+
+#endif /* ?PNG_1_0_X */
diff --git a/gs/libpng/pngmem.c b/gs/libpng/pngmem.c
new file mode 100644
index 000000000..f1cb69395
--- /dev/null
+++ b/gs/libpng/pngmem.c
@@ -0,0 +1,595 @@
+
+/* pngmem.c - stub functions for memory allocation
+ *
+ * libpng version 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file provides a location for all memory allocation.  Users who
+ * need special memory handling are expected to supply replacement
+ * functions for png_malloc() and png_free(), and to use
+ * png_create_read_struct_2() and png_create_write_struct_2() to
+ * identify the replacement functions.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+/* Borland DOS special memory handler */
+#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
+/* if you change this, be sure to change the one in png.h also */
+
+/* Allocate memory for a png_struct.  The malloc and memset can be replaced
+   by a single call to calloc() if this is thought to improve performance. */
+png_voidp /* PRIVATE */
+png_create_struct(int type)
+{
+#ifdef PNG_USER_MEM_SUPPORTED
+   return (png_create_struct_2(type, png_malloc_ptr_NULL, png_voidp_NULL));
+}
+
+/* Alternate version of png_create_struct, for use with user-defined malloc. */
+png_voidp /* PRIVATE */
+png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+   png_size_t size;
+   png_voidp struct_ptr;
+
+   if (type == PNG_STRUCT_INFO)
+     size = png_sizeof(png_info);
+   else if (type == PNG_STRUCT_PNG)
+     size = png_sizeof(png_struct);
+   else
+     return (png_get_copyright(NULL));
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   if(malloc_fn != NULL)
+   {
+      png_struct dummy_struct;
+      png_structp png_ptr = &dummy_struct;
+      png_ptr->mem_ptr=mem_ptr;
+      struct_ptr = (*(malloc_fn))(png_ptr, (png_uint_32)size);
+   }
+   else
+#endif /* PNG_USER_MEM_SUPPORTED */
+      struct_ptr = (png_voidp)farmalloc(size);
+   if (struct_ptr != NULL)
+      png_memset(struct_ptr, 0, size);
+   return (struct_ptr);
+}
+
+/* Free memory allocated by a png_create_struct() call */
+void /* PRIVATE */
+png_destroy_struct(png_voidp struct_ptr)
+{
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_destroy_struct_2(struct_ptr, png_free_ptr_NULL, png_voidp_NULL);
+}
+
+/* Free memory allocated by a png_create_struct() call */
+void /* PRIVATE */
+png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn,
+    png_voidp mem_ptr)
+{
+#endif
+   if (struct_ptr != NULL)
+   {
+#ifdef PNG_USER_MEM_SUPPORTED
+      if(free_fn != NULL)
+      {
+         png_struct dummy_struct;
+         png_structp png_ptr = &dummy_struct;
+         png_ptr->mem_ptr=mem_ptr;
+         (*(free_fn))(png_ptr, struct_ptr);
+         return;
+      }
+#endif /* PNG_USER_MEM_SUPPORTED */
+      farfree (struct_ptr);
+   }
+}
+
+/* Allocate memory.  For reasonable files, size should never exceed
+ * 64K.  However, zlib may allocate more then 64K if you don't tell
+ * it not to.  See zconf.h and png.h for more information. zlib does
+ * need to allocate exactly 64K, so whatever you call here must
+ * have the ability to do that.
+ *
+ * Borland seems to have a problem in DOS mode for exactly 64K.
+ * It gives you a segment with an offset of 8 (perhaps to store its
+ * memory stuff).  zlib doesn't like this at all, so we have to
+ * detect and deal with it.  This code should not be needed in
+ * Windows or OS/2 modes, and only in 16 bit mode.  This code has
+ * been updated by Alexander Lehmann for version 0.89 to waste less
+ * memory.
+ *
+ * Note that we can't use png_size_t for the "size" declaration,
+ * since on some systems a png_size_t is a 16-bit quantity, and as a
+ * result, we would be truncating potentially larger memory requests
+ * (which should cause a fatal error) and introducing major problems.
+ */
+
+png_voidp PNGAPI
+png_malloc(png_structp png_ptr, png_uint_32 size)
+{
+   png_voidp ret;
+
+   if (png_ptr == NULL || size == 0)
+      return (NULL);
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   if(png_ptr->malloc_fn != NULL)
+       ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size));
+   else
+       ret = (png_malloc_default(png_ptr, size));
+   if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+       png_error(png_ptr, "Out of memory!");
+   return (ret);
+}
+
+png_voidp PNGAPI
+png_malloc_default(png_structp png_ptr, png_uint_32 size)
+{
+   png_voidp ret;
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+#ifdef PNG_MAX_MALLOC_64K
+   if (size > (png_uint_32)65536L)
+   {
+      png_warning(png_ptr, "Cannot Allocate > 64K");
+      ret = NULL;
+   }
+   else
+#endif
+
+   if (size != (size_t)size)
+     ret = NULL;
+   else if (size == (png_uint_32)65536L)
+   {
+      if (png_ptr->offset_table == NULL)
+      {
+         /* try to see if we need to do any of this fancy stuff */
+         ret = farmalloc(size);
+         if (ret == NULL || ((png_size_t)ret & 0xffff))
+         {
+            int num_blocks;
+            png_uint_32 total_size;
+            png_bytep table;
+            int i;
+            png_byte huge * hptr;
+
+            if (ret != NULL)
+            {
+               farfree(ret);
+               ret = NULL;
+            }
+
+            if(png_ptr->zlib_window_bits > 14)
+               num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14));
+            else
+               num_blocks = 1;
+            if (png_ptr->zlib_mem_level >= 7)
+               num_blocks += (int)(1 << (png_ptr->zlib_mem_level - 7));
+            else
+               num_blocks++;
+
+            total_size = ((png_uint_32)65536L) * (png_uint_32)num_blocks+16;
+
+            table = farmalloc(total_size);
+
+            if (table == NULL)
+            {
+#ifndef PNG_USER_MEM_SUPPORTED
+               if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+                  png_error(png_ptr, "Out Of Memory."); /* Note "O" and "M" */
+               else
+                  png_warning(png_ptr, "Out Of Memory.");
+#endif
+               return (NULL);
+            }
+
+            if ((png_size_t)table & 0xfff0)
+            {
+#ifndef PNG_USER_MEM_SUPPORTED
+               if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+                  png_error(png_ptr,
+                    "Farmalloc didn't return normalized pointer");
+               else
+                  png_warning(png_ptr,
+                    "Farmalloc didn't return normalized pointer");
+#endif
+               return (NULL);
+            }
+
+            png_ptr->offset_table = table;
+            png_ptr->offset_table_ptr = farmalloc(num_blocks *
+               png_sizeof (png_bytep));
+
+            if (png_ptr->offset_table_ptr == NULL)
+            {
+#ifndef PNG_USER_MEM_SUPPORTED
+               if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+                  png_error(png_ptr, "Out Of memory."); /* Note "O" and "M" */
+               else
+                  png_warning(png_ptr, "Out Of memory.");
+#endif
+               return (NULL);
+            }
+
+            hptr = (png_byte huge *)table;
+            if ((png_size_t)hptr & 0xf)
+            {
+               hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
+               hptr = hptr + 16L;  /* "hptr += 16L" fails on Turbo C++ 3.0 */
+            }
+            for (i = 0; i < num_blocks; i++)
+            {
+               png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
+               hptr = hptr + (png_uint_32)65536L;  /* "+=" fails on TC++3.0 */
+            }
+
+            png_ptr->offset_table_number = num_blocks;
+            png_ptr->offset_table_count = 0;
+            png_ptr->offset_table_count_free = 0;
+         }
+      }
+
+      if (png_ptr->offset_table_count >= png_ptr->offset_table_number)
+      {
+#ifndef PNG_USER_MEM_SUPPORTED
+         if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+            png_error(png_ptr, "Out of Memory."); /* Note "o" and "M" */
+         else
+            png_warning(png_ptr, "Out of Memory.");
+#endif
+         return (NULL);
+      }
+
+      ret = png_ptr->offset_table_ptr[png_ptr->offset_table_count++];
+   }
+   else
+      ret = farmalloc(size);
+
+#ifndef PNG_USER_MEM_SUPPORTED
+   if (ret == NULL)
+   {
+      if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+         png_error(png_ptr, "Out of memory."); /* Note "o" and "m" */
+      else
+         png_warning(png_ptr, "Out of memory."); /* Note "o" and "m" */
+   }
+#endif
+
+   return (ret);
+}
+
+/* free a pointer allocated by png_malloc().  In the default
+   configuration, png_ptr is not used, but is passed in case it
+   is needed.  If ptr is NULL, return without taking any action. */
+void PNGAPI
+png_free(png_structp png_ptr, png_voidp ptr)
+{
+   if (png_ptr == NULL || ptr == NULL)
+      return;
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   if (png_ptr->free_fn != NULL)
+   {
+      (*(png_ptr->free_fn))(png_ptr, ptr);
+      return;
+   }
+   else png_free_default(png_ptr, ptr);
+}
+
+void PNGAPI
+png_free_default(png_structp png_ptr, png_voidp ptr)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+   if (png_ptr->offset_table != NULL)
+   {
+      int i;
+
+      for (i = 0; i < png_ptr->offset_table_count; i++)
+      {
+         if (ptr == png_ptr->offset_table_ptr[i])
+         {
+            ptr = NULL;
+            png_ptr->offset_table_count_free++;
+            break;
+         }
+      }
+      if (png_ptr->offset_table_count_free == png_ptr->offset_table_count)
+      {
+         farfree(png_ptr->offset_table);
+         farfree(png_ptr->offset_table_ptr);
+         png_ptr->offset_table = NULL;
+         png_ptr->offset_table_ptr = NULL;
+      }
+   }
+
+   if (ptr != NULL)
+   {
+      farfree(ptr);
+   }
+}
+
+#else /* Not the Borland DOS special memory handler */
+
+/* Allocate memory for a png_struct or a png_info.  The malloc and
+   memset can be replaced by a single call to calloc() if this is thought
+   to improve performance noticably. */
+png_voidp /* PRIVATE */
+png_create_struct(int type)
+{
+#ifdef PNG_USER_MEM_SUPPORTED
+   return (png_create_struct_2(type, png_malloc_ptr_NULL, png_voidp_NULL));
+}
+
+/* Allocate memory for a png_struct or a png_info.  The malloc and
+   memset can be replaced by a single call to calloc() if this is thought
+   to improve performance noticably. */
+png_voidp /* PRIVATE */
+png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+   png_size_t size;
+   png_voidp struct_ptr;
+
+   if (type == PNG_STRUCT_INFO)
+      size = png_sizeof(png_info);
+   else if (type == PNG_STRUCT_PNG)
+      size = png_sizeof(png_struct);
+   else
+      return (NULL);
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   if(malloc_fn != NULL)
+   {
+      png_struct dummy_struct;
+      png_structp png_ptr = &dummy_struct;
+      png_ptr->mem_ptr=mem_ptr;
+      struct_ptr = (*(malloc_fn))(png_ptr, size);
+      if (struct_ptr != NULL)
+         png_memset(struct_ptr, 0, size);
+      return (struct_ptr);
+   }
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+#if defined(__TURBOC__) && !defined(__FLAT__)
+   struct_ptr = (png_voidp)farmalloc(size);
+#else
+# if defined(_MSC_VER) && defined(MAXSEG_64K)
+   struct_ptr = (png_voidp)halloc(size,1);
+# else
+   struct_ptr = (png_voidp)malloc(size);
+# endif
+#endif
+   if (struct_ptr != NULL)
+      png_memset(struct_ptr, 0, size);
+
+   return (struct_ptr);
+}
+
+
+/* Free memory allocated by a png_create_struct() call */
+void /* PRIVATE */
+png_destroy_struct(png_voidp struct_ptr)
+{
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_destroy_struct_2(struct_ptr, png_free_ptr_NULL, png_voidp_NULL);
+}
+
+/* Free memory allocated by a png_create_struct() call */
+void /* PRIVATE */
+png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn,
+    png_voidp mem_ptr)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+   if (struct_ptr != NULL)
+   {
+#ifdef PNG_USER_MEM_SUPPORTED
+      if(free_fn != NULL)
+      {
+         png_struct dummy_struct;
+         png_structp png_ptr = &dummy_struct;
+         png_ptr->mem_ptr=mem_ptr;
+         (*(free_fn))(png_ptr, struct_ptr);
+         return;
+      }
+#endif /* PNG_USER_MEM_SUPPORTED */
+#if defined(__TURBOC__) && !defined(__FLAT__)
+      farfree(struct_ptr);
+#else
+# if defined(_MSC_VER) && defined(MAXSEG_64K)
+      hfree(struct_ptr);
+# else
+      free(struct_ptr);
+# endif
+#endif
+   }
+}
+
+/* Allocate memory.  For reasonable files, size should never exceed
+   64K.  However, zlib may allocate more then 64K if you don't tell
+   it not to.  See zconf.h and png.h for more information.  zlib does
+   need to allocate exactly 64K, so whatever you call here must
+   have the ability to do that. */
+
+png_voidp PNGAPI
+png_malloc(png_structp png_ptr, png_uint_32 size)
+{
+   png_voidp ret;
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   if (png_ptr == NULL || size == 0)
+      return (NULL);
+
+   if(png_ptr->malloc_fn != NULL)
+       ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size));
+   else
+       ret = (png_malloc_default(png_ptr, size));
+   if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+       png_error(png_ptr, "Out of Memory!");
+   return (ret);
+}
+
+png_voidp PNGAPI
+png_malloc_default(png_structp png_ptr, png_uint_32 size)
+{
+   png_voidp ret;
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+   if (png_ptr == NULL || size == 0)
+      return (NULL);
+
+#ifdef PNG_MAX_MALLOC_64K
+   if (size > (png_uint_32)65536L)
+   {
+#ifndef PNG_USER_MEM_SUPPORTED
+      if(png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+         png_error(png_ptr, "Cannot Allocate > 64K");
+      else
+#endif
+         return NULL;
+   }
+#endif
+
+ /* Check for overflow */
+#if defined(__TURBOC__) && !defined(__FLAT__)
+ if (size != (unsigned long)size)
+   ret = NULL;
+ else
+   ret = farmalloc(size);
+#else
+# if defined(_MSC_VER) && defined(MAXSEG_64K)
+ if (size != (unsigned long)size)
+   ret = NULL;
+ else
+   ret = halloc(size, 1);
+# else
+ if (size != (size_t)size)
+   ret = NULL;
+ else
+   ret = malloc((size_t)size);
+# endif
+#endif
+
+#ifndef PNG_USER_MEM_SUPPORTED
+   if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
+      png_error(png_ptr, "Out of Memory");
+#endif
+
+   return (ret);
+}
+
+/* Free a pointer allocated by png_malloc().  If ptr is NULL, return
+   without taking any action. */
+void PNGAPI
+png_free(png_structp png_ptr, png_voidp ptr)
+{
+   if (png_ptr == NULL || ptr == NULL)
+      return;
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   if (png_ptr->free_fn != NULL)
+   {
+      (*(png_ptr->free_fn))(png_ptr, ptr);
+      return;
+   }
+   else png_free_default(png_ptr, ptr);
+}
+void PNGAPI
+png_free_default(png_structp png_ptr, png_voidp ptr)
+{
+   if (png_ptr == NULL || ptr == NULL)
+      return;
+
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+#if defined(__TURBOC__) && !defined(__FLAT__)
+   farfree(ptr);
+#else
+# if defined(_MSC_VER) && defined(MAXSEG_64K)
+   hfree(ptr);
+# else
+   free(ptr);
+# endif
+#endif
+}
+
+#endif /* Not Borland DOS special memory handler */
+
+#if defined(PNG_1_0_X)
+#  define png_malloc_warn png_malloc
+#else
+/* This function was added at libpng version 1.2.3.  The png_malloc_warn()
+ * function will set up png_malloc() to issue a png_warning and return NULL
+ * instead of issuing a png_error, if it fails to allocate the requested
+ * memory.
+ */
+png_voidp PNGAPI
+png_malloc_warn(png_structp png_ptr, png_uint_32 size)
+{
+   png_voidp ptr;
+   png_uint_32 save_flags=png_ptr->flags;
+
+   png_ptr->flags|=PNG_FLAG_MALLOC_NULL_MEM_OK;
+   ptr = (png_voidp)png_malloc((png_structp)png_ptr, size);
+   png_ptr->flags=save_flags;
+   return(ptr);
+}
+#endif
+
+png_voidp PNGAPI
+png_memcpy_check (png_structp png_ptr, png_voidp s1, png_voidp s2,
+   png_uint_32 length)
+{
+   png_size_t size;
+
+   size = (png_size_t)length;
+   if ((png_uint_32)size != length)
+      png_error(png_ptr,"Overflow in png_memcpy_check.");
+
+   return(png_memcpy (s1, s2, size));
+}
+
+png_voidp PNGAPI
+png_memset_check (png_structp png_ptr, png_voidp s1, int value,
+   png_uint_32 length)
+{
+   png_size_t size;
+
+   size = (png_size_t)length;
+   if ((png_uint_32)size != length)
+      png_error(png_ptr,"Overflow in png_memset_check.");
+
+   return (png_memset (s1, value, size));
+
+}
+
+#ifdef PNG_USER_MEM_SUPPORTED
+/* This function is called when the application wants to use another method
+ * of allocating and freeing memory.
+ */
+void PNGAPI
+png_set_mem_fn(png_structp png_ptr, png_voidp mem_ptr, png_malloc_ptr
+  malloc_fn, png_free_ptr free_fn)
+{
+   png_ptr->mem_ptr = mem_ptr;
+   png_ptr->malloc_fn = malloc_fn;
+   png_ptr->free_fn = free_fn;
+}
+
+/* This function returns a pointer to the mem_ptr associated with the user
+ * functions.  The application should free any memory associated with this
+ * pointer before png_write_destroy and png_read_destroy are called.
+ */
+png_voidp PNGAPI
+png_get_mem_ptr(png_structp png_ptr)
+{
+   return ((png_voidp)png_ptr->mem_ptr);
+}
+#endif /* PNG_USER_MEM_SUPPORTED */
diff --git a/gs/libpng/pngnow.png b/gs/libpng/pngnow.png
new file mode 100644
index 000000000..82793ebdd
--- /dev/null
+++ b/gs/libpng/pngnow.png
diff --git a/gs/libpng/pngpread.c b/gs/libpng/pngpread.c
new file mode 100644
index 000000000..8c35faae4
--- /dev/null
+++ b/gs/libpng/pngpread.c
@@ -0,0 +1,1573 @@
+
+/* pngpread.c - read a png file in push mode
+ *
+ * libpng version 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+
+/* push model modes */
+#define PNG_READ_SIG_MODE   0
+#define PNG_READ_CHUNK_MODE 1
+#define PNG_READ_IDAT_MODE  2
+#define PNG_SKIP_MODE       3
+#define PNG_READ_tEXt_MODE  4
+#define PNG_READ_zTXt_MODE  5
+#define PNG_READ_DONE_MODE  6
+#define PNG_READ_iTXt_MODE  7
+#define PNG_ERROR_MODE      8
+
+void PNGAPI
+png_process_data(png_structp png_ptr, png_infop info_ptr,
+   png_bytep buffer, png_size_t buffer_size)
+{
+   png_push_restore_buffer(png_ptr, buffer, buffer_size);
+
+   while (png_ptr->buffer_size)
+   {
+      png_process_some_data(png_ptr, info_ptr);
+   }
+}
+
+/* What we do with the incoming data depends on what we were previously
+ * doing before we ran out of data...
+ */
+void /* PRIVATE */
+png_process_some_data(png_structp png_ptr, png_infop info_ptr)
+{
+   switch (png_ptr->process_mode)
+   {
+      case PNG_READ_SIG_MODE:
+      {
+         png_push_read_sig(png_ptr, info_ptr);
+         break;
+      }
+      case PNG_READ_CHUNK_MODE:
+      {
+         png_push_read_chunk(png_ptr, info_ptr);
+         break;
+      }
+      case PNG_READ_IDAT_MODE:
+      {
+         png_push_read_IDAT(png_ptr);
+         break;
+      }
+#if defined(PNG_READ_tEXt_SUPPORTED)
+      case PNG_READ_tEXt_MODE:
+      {
+         png_push_read_tEXt(png_ptr, info_ptr);
+         break;
+      }
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+      case PNG_READ_zTXt_MODE:
+      {
+         png_push_read_zTXt(png_ptr, info_ptr);
+         break;
+      }
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+      case PNG_READ_iTXt_MODE:
+      {
+         png_push_read_iTXt(png_ptr, info_ptr);
+         break;
+      }
+#endif
+      case PNG_SKIP_MODE:
+      {
+         png_push_crc_finish(png_ptr);
+         break;
+      }
+      default:
+      {
+         png_ptr->buffer_size = 0;
+         break;
+      }
+   }
+}
+
+/* Read any remaining signature bytes from the stream and compare them with
+ * the correct PNG signature.  It is possible that this routine is called
+ * with bytes already read from the signature, either because they have been
+ * checked by the calling application, or because of multiple calls to this
+ * routine.
+ */
+void /* PRIVATE */
+png_push_read_sig(png_structp png_ptr, png_infop info_ptr)
+{
+   png_size_t num_checked = png_ptr->sig_bytes,
+             num_to_check = 8 - num_checked;
+
+   if (png_ptr->buffer_size < num_to_check)
+   {
+      num_to_check = png_ptr->buffer_size;
+   }
+
+   png_push_fill_buffer(png_ptr, &(info_ptr->signature[num_checked]),
+      num_to_check);
+   png_ptr->sig_bytes = (png_byte)(png_ptr->sig_bytes+num_to_check);
+
+   if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
+   {
+      if (num_checked < 4 &&
+          png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
+         png_error(png_ptr, "Not a PNG file");
+      else
+         png_error(png_ptr, "PNG file corrupted by ASCII conversion");
+   }
+   else
+   {
+      if (png_ptr->sig_bytes >= 8)
+      {
+         png_ptr->process_mode = PNG_READ_CHUNK_MODE;
+      }
+   }
+}
+
+void /* PRIVATE */
+png_push_read_chunk(png_structp png_ptr, png_infop info_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+      PNG_IHDR;
+      PNG_IDAT;
+      PNG_IEND;
+      PNG_PLTE;
+#if defined(PNG_READ_bKGD_SUPPORTED)
+      PNG_bKGD;
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+      PNG_cHRM;
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+      PNG_gAMA;
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+      PNG_hIST;
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+      PNG_iCCP;
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+      PNG_iTXt;
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+      PNG_oFFs;
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+      PNG_pCAL;
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+      PNG_pHYs;
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+      PNG_sBIT;
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+      PNG_sCAL;
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+      PNG_sRGB;
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+      PNG_sPLT;
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+      PNG_tEXt;
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+      PNG_tIME;
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+      PNG_tRNS;
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+      PNG_zTXt;
+#endif
+#endif /* PNG_USE_LOCAL_ARRAYS */
+   /* First we make sure we have enough data for the 4 byte chunk name
+    * and the 4 byte chunk length before proceeding with decoding the
+    * chunk data.  To fully decode each of these chunks, we also make
+    * sure we have enough data in the buffer for the 4 byte CRC at the
+    * end of every chunk (except IDAT, which is handled separately).
+    */
+   if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
+   {
+      png_byte chunk_length[4];
+
+      if (png_ptr->buffer_size < 8)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+
+      png_push_fill_buffer(png_ptr, chunk_length, 4);
+      png_ptr->push_length = png_get_uint_31(png_ptr,chunk_length);
+      png_reset_crc(png_ptr);
+      png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+      png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
+   }
+
+   if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_IHDR(png_ptr, info_ptr, png_ptr->push_length);
+   }
+   else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_IEND(png_ptr, info_ptr, png_ptr->push_length);
+
+      png_ptr->process_mode = PNG_READ_DONE_MODE;
+      png_push_have_end(png_ptr, info_ptr);
+   }
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+   else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+         png_ptr->mode |= PNG_HAVE_IDAT;
+      png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
+      if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+         png_ptr->mode |= PNG_HAVE_PLTE;
+      else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+      {
+         if (!(png_ptr->mode & PNG_HAVE_IHDR))
+            png_error(png_ptr, "Missing IHDR before IDAT");
+         else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+                  !(png_ptr->mode & PNG_HAVE_PLTE))
+            png_error(png_ptr, "Missing PLTE before IDAT");
+      }
+   }
+#endif
+   else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_PLTE(png_ptr, info_ptr, png_ptr->push_length);
+   }
+   else if (!png_memcmp(png_ptr->chunk_name, (png_bytep)png_IDAT, 4))
+   {
+      /* If we reach an IDAT chunk, this means we have read all of the
+       * header chunks, and we can start reading the image (or if this
+       * is called after the image has been read - we have an error).
+       */
+     if (!(png_ptr->mode & PNG_HAVE_IHDR))
+       png_error(png_ptr, "Missing IHDR before IDAT");
+     else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+         !(png_ptr->mode & PNG_HAVE_PLTE))
+       png_error(png_ptr, "Missing PLTE before IDAT");
+
+      if (png_ptr->mode & PNG_HAVE_IDAT)
+      {
+         if (png_ptr->push_length == 0)
+            return;
+
+         if (png_ptr->mode & PNG_AFTER_IDAT)
+            png_error(png_ptr, "Too many IDAT's found");
+      }
+
+      png_ptr->idat_size = png_ptr->push_length;
+      png_ptr->mode |= PNG_HAVE_IDAT;
+      png_ptr->process_mode = PNG_READ_IDAT_MODE;
+      png_push_have_info(png_ptr, info_ptr);
+      png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
+      png_ptr->zstream.next_out = png_ptr->row_buf;
+      return;
+   }
+#if defined(PNG_READ_gAMA_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_gAMA(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_sBIT(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_cHRM(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_sRGB(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_iCCP(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_sPLT(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_tRNS(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_bKGD_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_bKGD(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_hIST(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_pHYs(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_oFFs(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_pCAL(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_sCAL(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_handle_tIME(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_push_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_push_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+   else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_push_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length);
+   }
+#endif
+   else
+   {
+      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+      png_push_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
+   }
+
+   png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
+}
+
+void /* PRIVATE */
+png_push_crc_skip(png_structp png_ptr, png_uint_32 skip)
+{
+   png_ptr->process_mode = PNG_SKIP_MODE;
+   png_ptr->skip_length = skip;
+}
+
+void /* PRIVATE */
+png_push_crc_finish(png_structp png_ptr)
+{
+   if (png_ptr->skip_length && png_ptr->save_buffer_size)
+   {
+      png_size_t save_size;
+
+      if (png_ptr->skip_length < (png_uint_32)png_ptr->save_buffer_size)
+         save_size = (png_size_t)png_ptr->skip_length;
+      else
+         save_size = png_ptr->save_buffer_size;
+
+      png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
+
+      png_ptr->skip_length -= save_size;
+      png_ptr->buffer_size -= save_size;
+      png_ptr->save_buffer_size -= save_size;
+      png_ptr->save_buffer_ptr += save_size;
+   }
+   if (png_ptr->skip_length && png_ptr->current_buffer_size)
+   {
+      png_size_t save_size;
+
+      if (png_ptr->skip_length < (png_uint_32)png_ptr->current_buffer_size)
+         save_size = (png_size_t)png_ptr->skip_length;
+      else
+         save_size = png_ptr->current_buffer_size;
+
+      png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
+
+      png_ptr->skip_length -= save_size;
+      png_ptr->buffer_size -= save_size;
+      png_ptr->current_buffer_size -= save_size;
+      png_ptr->current_buffer_ptr += save_size;
+   }
+   if (!png_ptr->skip_length)
+   {
+      if (png_ptr->buffer_size < 4)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+
+      png_crc_finish(png_ptr, 0);
+      png_ptr->process_mode = PNG_READ_CHUNK_MODE;
+   }
+}
+
+void PNGAPI
+png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
+{
+   png_bytep ptr;
+
+   ptr = buffer;
+   if (png_ptr->save_buffer_size)
+   {
+      png_size_t save_size;
+
+      if (length < png_ptr->save_buffer_size)
+         save_size = length;
+      else
+         save_size = png_ptr->save_buffer_size;
+
+      png_memcpy(ptr, png_ptr->save_buffer_ptr, save_size);
+      length -= save_size;
+      ptr += save_size;
+      png_ptr->buffer_size -= save_size;
+      png_ptr->save_buffer_size -= save_size;
+      png_ptr->save_buffer_ptr += save_size;
+   }
+   if (length && png_ptr->current_buffer_size)
+   {
+      png_size_t save_size;
+
+      if (length < png_ptr->current_buffer_size)
+         save_size = length;
+      else
+         save_size = png_ptr->current_buffer_size;
+
+      png_memcpy(ptr, png_ptr->current_buffer_ptr, save_size);
+      png_ptr->buffer_size -= save_size;
+      png_ptr->current_buffer_size -= save_size;
+      png_ptr->current_buffer_ptr += save_size;
+   }
+}
+
+void /* PRIVATE */
+png_push_save_buffer(png_structp png_ptr)
+{
+   if (png_ptr->save_buffer_size)
+   {
+      if (png_ptr->save_buffer_ptr != png_ptr->save_buffer)
+      {
+         png_size_t i,istop;
+         png_bytep sp;
+         png_bytep dp;
+
+         istop = png_ptr->save_buffer_size;
+         for (i = 0, sp = png_ptr->save_buffer_ptr, dp = png_ptr->save_buffer;
+            i < istop; i++, sp++, dp++)
+         {
+            *dp = *sp;
+         }
+      }
+   }
+   if (png_ptr->save_buffer_size + png_ptr->current_buffer_size >
+      png_ptr->save_buffer_max)
+   {
+      png_size_t new_max;
+      png_bytep old_buffer;
+
+      if (png_ptr->save_buffer_size > PNG_SIZE_MAX - 
+         (png_ptr->current_buffer_size + 256))
+      {
+        png_error(png_ptr, "Potential overflow of save_buffer");
+      }
+      new_max = png_ptr->save_buffer_size + png_ptr->current_buffer_size + 256;
+      old_buffer = png_ptr->save_buffer;
+      png_ptr->save_buffer = (png_bytep)png_malloc(png_ptr,
+         (png_uint_32)new_max);
+      png_memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
+      png_free(png_ptr, old_buffer);
+      png_ptr->save_buffer_max = new_max;
+   }
+   if (png_ptr->current_buffer_size)
+   {
+      png_memcpy(png_ptr->save_buffer + png_ptr->save_buffer_size,
+         png_ptr->current_buffer_ptr, png_ptr->current_buffer_size);
+      png_ptr->save_buffer_size += png_ptr->current_buffer_size;
+      png_ptr->current_buffer_size = 0;
+   }
+   png_ptr->save_buffer_ptr = png_ptr->save_buffer;
+   png_ptr->buffer_size = 0;
+}
+
+void /* PRIVATE */
+png_push_restore_buffer(png_structp png_ptr, png_bytep buffer,
+   png_size_t buffer_length)
+{
+   png_ptr->current_buffer = buffer;
+   png_ptr->current_buffer_size = buffer_length;
+   png_ptr->buffer_size = buffer_length + png_ptr->save_buffer_size;
+   png_ptr->current_buffer_ptr = png_ptr->current_buffer;
+}
+
+void /* PRIVATE */
+png_push_read_IDAT(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_IDAT;
+#endif
+   if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
+   {
+      png_byte chunk_length[4];
+
+      if (png_ptr->buffer_size < 8)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+
+      png_push_fill_buffer(png_ptr, chunk_length, 4);
+      png_ptr->push_length = png_get_uint_31(png_ptr,chunk_length);
+      png_reset_crc(png_ptr);
+      png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+      png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
+
+      if (png_memcmp(png_ptr->chunk_name, (png_bytep)png_IDAT, 4))
+      {
+         png_ptr->process_mode = PNG_READ_CHUNK_MODE;
+         if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
+            png_error(png_ptr, "Not enough compressed data");
+         return;
+      }
+
+      png_ptr->idat_size = png_ptr->push_length;
+   }
+   if (png_ptr->idat_size && png_ptr->save_buffer_size)
+   {
+      png_size_t save_size;
+
+      if (png_ptr->idat_size < (png_uint_32)png_ptr->save_buffer_size)
+      {
+         save_size = (png_size_t)png_ptr->idat_size;
+         /* check for overflow */
+         if((png_uint_32)save_size != png_ptr->idat_size)
+            png_error(png_ptr, "save_size overflowed in pngpread");
+      }
+      else
+         save_size = png_ptr->save_buffer_size;
+
+      png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
+      if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
+         png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size);
+      png_ptr->idat_size -= save_size;
+      png_ptr->buffer_size -= save_size;
+      png_ptr->save_buffer_size -= save_size;
+      png_ptr->save_buffer_ptr += save_size;
+   }
+   if (png_ptr->idat_size && png_ptr->current_buffer_size)
+   {
+      png_size_t save_size;
+
+      if (png_ptr->idat_size < (png_uint_32)png_ptr->current_buffer_size)
+      {
+         save_size = (png_size_t)png_ptr->idat_size;
+         /* check for overflow */
+         if((png_uint_32)save_size != png_ptr->idat_size)
+            png_error(png_ptr, "save_size overflowed in pngpread");
+      }
+      else
+         save_size = png_ptr->current_buffer_size;
+
+      png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
+      if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
+        png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size);
+
+      png_ptr->idat_size -= save_size;
+      png_ptr->buffer_size -= save_size;
+      png_ptr->current_buffer_size -= save_size;
+      png_ptr->current_buffer_ptr += save_size;
+   }
+   if (!png_ptr->idat_size)
+   {
+      if (png_ptr->buffer_size < 4)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+
+      png_crc_finish(png_ptr, 0);
+      png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
+      png_ptr->mode |= PNG_AFTER_IDAT;
+   }
+}
+
+void /* PRIVATE */
+png_process_IDAT_data(png_structp png_ptr, png_bytep buffer,
+   png_size_t buffer_length)
+{
+   int ret;
+
+   if ((png_ptr->flags & PNG_FLAG_ZLIB_FINISHED) && buffer_length)
+      png_error(png_ptr, "Extra compression data");
+
+   png_ptr->zstream.next_in = buffer;
+   png_ptr->zstream.avail_in = (uInt)buffer_length;
+   for(;;)
+   {
+      ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+      if (ret != Z_OK)
+      {
+         if (ret == Z_STREAM_END)
+         {
+            if (png_ptr->zstream.avail_in)
+               png_error(png_ptr, "Extra compressed data");
+            if (!(png_ptr->zstream.avail_out))
+            {
+               png_push_process_row(png_ptr);
+            }
+
+            png_ptr->mode |= PNG_AFTER_IDAT;
+            png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
+            break;
+         }
+         else if (ret == Z_BUF_ERROR)
+            break;
+         else
+            png_error(png_ptr, "Decompression Error");
+      }
+      if (!(png_ptr->zstream.avail_out))
+      {
+         if ((
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+             png_ptr->interlaced && png_ptr->pass > 6) ||
+             (!png_ptr->interlaced &&
+#endif
+             png_ptr->row_number == png_ptr->num_rows))
+         {
+           if (png_ptr->zstream.avail_in)
+             png_warning(png_ptr, "Too much data in IDAT chunks");
+           png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
+           break;
+         }
+         png_push_process_row(png_ptr);
+         png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
+         png_ptr->zstream.next_out = png_ptr->row_buf;
+      }
+      else
+         break;
+   }
+}
+
+void /* PRIVATE */
+png_push_process_row(png_structp png_ptr)
+{
+   png_ptr->row_info.color_type = png_ptr->color_type;
+   png_ptr->row_info.width = png_ptr->iwidth;
+   png_ptr->row_info.channels = png_ptr->channels;
+   png_ptr->row_info.bit_depth = png_ptr->bit_depth;
+   png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
+
+   png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
+       png_ptr->row_info.width);
+
+   png_read_filter_row(png_ptr, &(png_ptr->row_info),
+      png_ptr->row_buf + 1, png_ptr->prev_row + 1,
+      (int)(png_ptr->row_buf[0]));
+
+   png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
+      png_ptr->rowbytes + 1);
+
+   if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
+      png_do_read_transformations(png_ptr);
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+   /* blow up interlaced rows to full size */
+   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+   {
+      if (png_ptr->pass < 6)
+/*       old interface (pre-1.0.9):
+         png_do_read_interlace(&(png_ptr->row_info),
+            png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
+ */
+         png_do_read_interlace(png_ptr);
+
+    switch (png_ptr->pass)
+    {
+         case 0:
+         {
+            int i;
+            for (i = 0; i < 8 && png_ptr->pass == 0; i++)
+            {
+               png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+               png_read_push_finish_row(png_ptr); /* updates png_ptr->pass */
+            }
+            if (png_ptr->pass == 2) /* pass 1 might be empty */
+            {
+               for (i = 0; i < 4 && png_ptr->pass == 2; i++)
+               {
+                  png_push_have_row(png_ptr, png_bytep_NULL);
+                  png_read_push_finish_row(png_ptr);
+               }
+            }
+            if (png_ptr->pass == 4 && png_ptr->height <= 4)
+            {
+               for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+               {
+                  png_push_have_row(png_ptr, png_bytep_NULL);
+                  png_read_push_finish_row(png_ptr);
+               }
+            }
+            if (png_ptr->pass == 6 && png_ptr->height <= 4)
+            {
+                png_push_have_row(png_ptr, png_bytep_NULL);
+                png_read_push_finish_row(png_ptr);
+            }
+            break;
+         }
+         case 1:
+         {
+            int i;
+            for (i = 0; i < 8 && png_ptr->pass == 1; i++)
+            {
+               png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+               png_read_push_finish_row(png_ptr);
+            }
+            if (png_ptr->pass == 2) /* skip top 4 generated rows */
+            {
+               for (i = 0; i < 4 && png_ptr->pass == 2; i++)
+               {
+                  png_push_have_row(png_ptr, png_bytep_NULL);
+                  png_read_push_finish_row(png_ptr);
+               }
+            }
+            break;
+         }
+         case 2:
+         {
+            int i;
+            for (i = 0; i < 4 && png_ptr->pass == 2; i++)
+            {
+               png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+               png_read_push_finish_row(png_ptr);
+            }
+            for (i = 0; i < 4 && png_ptr->pass == 2; i++)
+            {
+               png_push_have_row(png_ptr, png_bytep_NULL);
+               png_read_push_finish_row(png_ptr);
+            }
+            if (png_ptr->pass == 4) /* pass 3 might be empty */
+            {
+               for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+               {
+                  png_push_have_row(png_ptr, png_bytep_NULL);
+                  png_read_push_finish_row(png_ptr);
+               }
+            }
+            break;
+         }
+         case 3:
+         {
+            int i;
+            for (i = 0; i < 4 && png_ptr->pass == 3; i++)
+            {
+               png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+               png_read_push_finish_row(png_ptr);
+            }
+            if (png_ptr->pass == 4) /* skip top two generated rows */
+            {
+               for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+               {
+                  png_push_have_row(png_ptr, png_bytep_NULL);
+                  png_read_push_finish_row(png_ptr);
+               }
+            }
+            break;
+         }
+         case 4:
+         {
+            int i;
+            for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+            {
+               png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+               png_read_push_finish_row(png_ptr);
+            }
+            for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+            {
+               png_push_have_row(png_ptr, png_bytep_NULL);
+               png_read_push_finish_row(png_ptr);
+            }
+            if (png_ptr->pass == 6) /* pass 5 might be empty */
+            {
+               png_push_have_row(png_ptr, png_bytep_NULL);
+               png_read_push_finish_row(png_ptr);
+            }
+            break;
+         }
+         case 5:
+         {
+            int i;
+            for (i = 0; i < 2 && png_ptr->pass == 5; i++)
+            {
+               png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+               png_read_push_finish_row(png_ptr);
+            }
+            if (png_ptr->pass == 6) /* skip top generated row */
+            {
+               png_push_have_row(png_ptr, png_bytep_NULL);
+               png_read_push_finish_row(png_ptr);
+            }
+            break;
+         }
+         case 6:
+         {
+            png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+            png_read_push_finish_row(png_ptr);
+            if (png_ptr->pass != 6)
+               break;
+            png_push_have_row(png_ptr, png_bytep_NULL);
+            png_read_push_finish_row(png_ptr);
+         }
+      }
+   }
+   else
+#endif
+   {
+      png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+      png_read_push_finish_row(png_ptr);
+   }
+}
+
+void /* PRIVATE */
+png_read_push_finish_row(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+   /* start of interlace block */
+   const int FARDATA png_pass_start[] = {0, 4, 0, 2, 0, 1, 0};
+
+   /* offset to next interlace block */
+   const int FARDATA png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
+
+   /* start of interlace block in the y direction */
+   const int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
+
+   /* offset to next interlace block in the y direction */
+   const int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
+
+   /* Width of interlace block.  This is not currently used - if you need
+    * it, uncomment it here and in png.h
+   const int FARDATA png_pass_width[] = {8, 4, 4, 2, 2, 1, 1};
+   */
+
+   /* Height of interlace block.  This is not currently used - if you need
+    * it, uncomment it here and in png.h
+   const int FARDATA png_pass_height[] = {8, 8, 4, 4, 2, 2, 1};
+   */
+#endif
+
+   png_ptr->row_number++;
+   if (png_ptr->row_number < png_ptr->num_rows)
+      return;
+
+   if (png_ptr->interlaced)
+   {
+      png_ptr->row_number = 0;
+      png_memset_check(png_ptr, png_ptr->prev_row, 0,
+         png_ptr->rowbytes + 1);
+      do
+      {
+         png_ptr->pass++;
+         if ((png_ptr->pass == 1 && png_ptr->width < 5) ||
+             (png_ptr->pass == 3 && png_ptr->width < 3) ||
+             (png_ptr->pass == 5 && png_ptr->width < 2))
+           png_ptr->pass++;
+
+         if (png_ptr->pass > 7)
+            png_ptr->pass--;
+         if (png_ptr->pass >= 7)
+            break;
+
+         png_ptr->iwidth = (png_ptr->width +
+            png_pass_inc[png_ptr->pass] - 1 -
+            png_pass_start[png_ptr->pass]) /
+            png_pass_inc[png_ptr->pass];
+
+         png_ptr->irowbytes = PNG_ROWBYTES(png_ptr->pixel_depth,
+            png_ptr->iwidth) + 1;
+
+         if (png_ptr->transformations & PNG_INTERLACE)
+            break;
+
+         png_ptr->num_rows = (png_ptr->height +
+            png_pass_yinc[png_ptr->pass] - 1 -
+            png_pass_ystart[png_ptr->pass]) /
+            png_pass_yinc[png_ptr->pass];
+
+      } while (png_ptr->iwidth == 0 || png_ptr->num_rows == 0);
+   }
+}
+
+#if defined(PNG_READ_tEXt_SUPPORTED)
+void /* PRIVATE */
+png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
+   length)
+{
+   if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
+      {
+         png_error(png_ptr, "Out of place tEXt");
+         /* to quiet some compiler warnings */
+         if(info_ptr == NULL) return;
+      }
+
+#ifdef PNG_MAX_MALLOC_64K
+   png_ptr->skip_length = 0;  /* This may not be necessary */
+
+   if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */
+   {
+      png_warning(png_ptr, "tEXt chunk too large to fit in memory");
+      png_ptr->skip_length = length - (png_uint_32)65535L;
+      length = (png_uint_32)65535L;
+   }
+#endif
+
+   png_ptr->current_text = (png_charp)png_malloc(png_ptr,
+         (png_uint_32)(length+1));
+   png_ptr->current_text[length] = '\0';
+   png_ptr->current_text_ptr = png_ptr->current_text;
+   png_ptr->current_text_size = (png_size_t)length;
+   png_ptr->current_text_left = (png_size_t)length;
+   png_ptr->process_mode = PNG_READ_tEXt_MODE;
+}
+
+void /* PRIVATE */
+png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr->buffer_size && png_ptr->current_text_left)
+   {
+      png_size_t text_size;
+
+      if (png_ptr->buffer_size < png_ptr->current_text_left)
+         text_size = png_ptr->buffer_size;
+      else
+         text_size = png_ptr->current_text_left;
+      png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
+      png_ptr->current_text_left -= text_size;
+      png_ptr->current_text_ptr += text_size;
+   }
+   if (!(png_ptr->current_text_left))
+   {
+      png_textp text_ptr;
+      png_charp text;
+      png_charp key;
+      int ret;
+
+      if (png_ptr->buffer_size < 4)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+
+      png_push_crc_finish(png_ptr);
+
+#if defined(PNG_MAX_MALLOC_64K)
+      if (png_ptr->skip_length)
+         return;
+#endif
+
+      key = png_ptr->current_text;
+
+      for (text = key; *text; text++)
+         /* empty loop */ ;
+
+      if (text != key + png_ptr->current_text_size)
+         text++;
+
+      text_ptr = (png_textp)png_malloc(png_ptr,
+         (png_uint_32)png_sizeof(png_text));
+      text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
+      text_ptr->key = key;
+#ifdef PNG_iTXt_SUPPORTED
+      text_ptr->lang = NULL;
+      text_ptr->lang_key = NULL;
+#endif
+      text_ptr->text = text;
+
+      ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+      png_free(png_ptr, key);
+      png_free(png_ptr, text_ptr);
+      png_ptr->current_text = NULL;
+
+      if (ret)
+        png_warning(png_ptr, "Insufficient memory to store text chunk.");
+   }
+}
+#endif
+
+#if defined(PNG_READ_zTXt_SUPPORTED)
+void /* PRIVATE */
+png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
+   length)
+{
+   if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
+      {
+         png_error(png_ptr, "Out of place zTXt");
+         /* to quiet some compiler warnings */
+         if(info_ptr == NULL) return;
+      }
+
+#ifdef PNG_MAX_MALLOC_64K
+   /* We can't handle zTXt chunks > 64K, since we don't have enough space
+    * to be able to store the uncompressed data.  Actually, the threshold
+    * is probably around 32K, but it isn't as definite as 64K is.
+    */
+   if (length > (png_uint_32)65535L)
+   {
+      png_warning(png_ptr, "zTXt chunk too large to fit in memory");
+      png_push_crc_skip(png_ptr, length);
+      return;
+   }
+#endif
+
+   png_ptr->current_text = (png_charp)png_malloc(png_ptr,
+       (png_uint_32)(length+1));
+   png_ptr->current_text[length] = '\0';
+   png_ptr->current_text_ptr = png_ptr->current_text;
+   png_ptr->current_text_size = (png_size_t)length;
+   png_ptr->current_text_left = (png_size_t)length;
+   png_ptr->process_mode = PNG_READ_zTXt_MODE;
+}
+
+void /* PRIVATE */
+png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr->buffer_size && png_ptr->current_text_left)
+   {
+      png_size_t text_size;
+
+      if (png_ptr->buffer_size < (png_uint_32)png_ptr->current_text_left)
+         text_size = png_ptr->buffer_size;
+      else
+         text_size = png_ptr->current_text_left;
+      png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
+      png_ptr->current_text_left -= text_size;
+      png_ptr->current_text_ptr += text_size;
+   }
+   if (!(png_ptr->current_text_left))
+   {
+      png_textp text_ptr;
+      png_charp text;
+      png_charp key;
+      int ret;
+      png_size_t text_size, key_size;
+
+      if (png_ptr->buffer_size < 4)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+
+      png_push_crc_finish(png_ptr);
+
+      key = png_ptr->current_text;
+
+      for (text = key; *text; text++)
+         /* empty loop */ ;
+
+      /* zTXt can't have zero text */
+      if (text == key + png_ptr->current_text_size)
+      {
+         png_ptr->current_text = NULL;
+         png_free(png_ptr, key);
+         return;
+      }
+
+      text++;
+
+      if (*text != PNG_TEXT_COMPRESSION_zTXt) /* check compression byte */
+      {
+         png_ptr->current_text = NULL;
+         png_free(png_ptr, key);
+         return;
+      }
+
+      text++;
+
+      png_ptr->zstream.next_in = (png_bytep )text;
+      png_ptr->zstream.avail_in = (uInt)(png_ptr->current_text_size -
+         (text - key));
+      png_ptr->zstream.next_out = png_ptr->zbuf;
+      png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+
+      key_size = text - key;
+      text_size = 0;
+      text = NULL;
+      ret = Z_STREAM_END;
+
+      while (png_ptr->zstream.avail_in)
+      {
+         ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+         if (ret != Z_OK && ret != Z_STREAM_END)
+         {
+            inflateReset(&png_ptr->zstream);
+            png_ptr->zstream.avail_in = 0;
+            png_ptr->current_text = NULL;
+            png_free(png_ptr, key);
+            png_free(png_ptr, text);
+            return;
+         }
+         if (!(png_ptr->zstream.avail_out) || ret == Z_STREAM_END)
+         {
+            if (text == NULL)
+            {
+               text = (png_charp)png_malloc(png_ptr,
+                  (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out
+                     + key_size + 1));
+               png_memcpy(text + key_size, png_ptr->zbuf,
+                  png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+               png_memcpy(text, key, key_size);
+               text_size = key_size + png_ptr->zbuf_size -
+                  png_ptr->zstream.avail_out;
+               *(text + text_size) = '\0';
+            }
+            else
+            {
+               png_charp tmp;
+
+               tmp = text;
+               text = (png_charp)png_malloc(png_ptr, text_size +
+                  (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out
+                   + 1));
+               png_memcpy(text, tmp, text_size);
+               png_free(png_ptr, tmp);
+               png_memcpy(text + text_size, png_ptr->zbuf,
+                  png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+               text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;
+               *(text + text_size) = '\0';
+            }
+            if (ret != Z_STREAM_END)
+            {
+               png_ptr->zstream.next_out = png_ptr->zbuf;
+               png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+            }
+         }
+         else
+         {
+            break;
+         }
+
+         if (ret == Z_STREAM_END)
+            break;
+      }
+
+      inflateReset(&png_ptr->zstream);
+      png_ptr->zstream.avail_in = 0;
+
+      if (ret != Z_STREAM_END)
+      {
+         png_ptr->current_text = NULL;
+         png_free(png_ptr, key);
+         png_free(png_ptr, text);
+         return;
+      }
+
+      png_ptr->current_text = NULL;
+      png_free(png_ptr, key);
+      key = text;
+      text += key_size;
+
+      text_ptr = (png_textp)png_malloc(png_ptr,
+          (png_uint_32)png_sizeof(png_text));
+      text_ptr->compression = PNG_TEXT_COMPRESSION_zTXt;
+      text_ptr->key = key;
+#ifdef PNG_iTXt_SUPPORTED
+      text_ptr->lang = NULL;
+      text_ptr->lang_key = NULL;
+#endif
+      text_ptr->text = text;
+
+      ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+      png_free(png_ptr, key);
+      png_free(png_ptr, text_ptr);
+
+      if (ret)
+        png_warning(png_ptr, "Insufficient memory to store text chunk.");
+   }
+}
+#endif
+
+#if defined(PNG_READ_iTXt_SUPPORTED)
+void /* PRIVATE */
+png_push_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
+   length)
+{
+   if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
+      {
+         png_error(png_ptr, "Out of place iTXt");
+         /* to quiet some compiler warnings */
+         if(info_ptr == NULL) return;
+      }
+
+#ifdef PNG_MAX_MALLOC_64K
+   png_ptr->skip_length = 0;  /* This may not be necessary */
+
+   if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */
+   {
+      png_warning(png_ptr, "iTXt chunk too large to fit in memory");
+      png_ptr->skip_length = length - (png_uint_32)65535L;
+      length = (png_uint_32)65535L;
+   }
+#endif
+
+   png_ptr->current_text = (png_charp)png_malloc(png_ptr,
+         (png_uint_32)(length+1));
+   png_ptr->current_text[length] = '\0';
+   png_ptr->current_text_ptr = png_ptr->current_text;
+   png_ptr->current_text_size = (png_size_t)length;
+   png_ptr->current_text_left = (png_size_t)length;
+   png_ptr->process_mode = PNG_READ_iTXt_MODE;
+}
+
+void /* PRIVATE */
+png_push_read_iTXt(png_structp png_ptr, png_infop info_ptr)
+{
+
+   if (png_ptr->buffer_size && png_ptr->current_text_left)
+   {
+      png_size_t text_size;
+
+      if (png_ptr->buffer_size < png_ptr->current_text_left)
+         text_size = png_ptr->buffer_size;
+      else
+         text_size = png_ptr->current_text_left;
+      png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
+      png_ptr->current_text_left -= text_size;
+      png_ptr->current_text_ptr += text_size;
+   }
+   if (!(png_ptr->current_text_left))
+   {
+      png_textp text_ptr;
+      png_charp key;
+      int comp_flag;
+      png_charp lang;
+      png_charp lang_key;
+      png_charp text;
+      int ret;
+
+      if (png_ptr->buffer_size < 4)
+      {
+         png_push_save_buffer(png_ptr);
+         return;
+      }
+
+      png_push_crc_finish(png_ptr);
+
+#if defined(PNG_MAX_MALLOC_64K)
+      if (png_ptr->skip_length)
+         return;
+#endif
+
+      key = png_ptr->current_text;
+
+      for (lang = key; *lang; lang++)
+         /* empty loop */ ;
+
+      if (lang != key + png_ptr->current_text_size)
+         lang++;
+
+      comp_flag = *lang++;
+      lang++;     /* skip comp_type, always zero */
+
+      for (lang_key = lang; *lang_key; lang_key++)
+         /* empty loop */ ;
+      lang_key++;        /* skip NUL separator */
+
+      for (text = lang_key; *text; text++)
+         /* empty loop */ ;
+
+      if (text != key + png_ptr->current_text_size)
+         text++;
+
+      text_ptr = (png_textp)png_malloc(png_ptr,
+         (png_uint_32)png_sizeof(png_text));
+      text_ptr->compression = comp_flag + 2;
+      text_ptr->key = key;
+      text_ptr->lang = lang;
+      text_ptr->lang_key = lang_key;
+      text_ptr->text = text;
+      text_ptr->text_length = 0;
+      text_ptr->itxt_length = png_strlen(text);
+
+      ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+      png_ptr->current_text = NULL;
+
+      png_free(png_ptr, text_ptr);
+      if (ret)
+        png_warning(png_ptr, "Insufficient memory to store iTXt chunk.");
+   }
+}
+#endif
+
+/* This function is called when we haven't found a handler for this
+ * chunk.  If there isn't a problem with the chunk itself (ie a bad chunk
+ * name or a critical chunk), the chunk is (currently) silently ignored.
+ */
+void /* PRIVATE */
+png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32
+   length)
+{
+   png_uint_32 skip=0;
+   png_check_chunk_name(png_ptr, png_ptr->chunk_name);
+
+   if (!(png_ptr->chunk_name[0] & 0x20))
+   {
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+      if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
+           PNG_HANDLE_CHUNK_ALWAYS
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+           && png_ptr->read_user_chunk_fn == NULL
+#endif
+         )
+#endif
+         png_chunk_error(png_ptr, "unknown critical chunk");
+
+      /* to quiet compiler warnings about unused info_ptr */
+      if (info_ptr == NULL)
+         return;
+   }
+
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+   if (png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS)
+   {
+       png_unknown_chunk chunk;
+
+#ifdef PNG_MAX_MALLOC_64K
+       if (length > (png_uint_32)65535L)
+       {
+           png_warning(png_ptr, "unknown chunk too large to fit in memory");
+           skip = length - (png_uint_32)65535L;
+           length = (png_uint_32)65535L;
+       }
+#endif
+
+       png_strcpy((png_charp)chunk.name, (png_charp)png_ptr->chunk_name);
+       chunk.data = (png_bytep)png_malloc(png_ptr, length);
+       png_crc_read(png_ptr, chunk.data, length);
+       chunk.size = length;
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+       if(png_ptr->read_user_chunk_fn != NULL)
+       {
+          /* callback to user unknown chunk handler */
+          if ((*(png_ptr->read_user_chunk_fn)) (png_ptr, &chunk) <= 0)
+          {
+             if (!(png_ptr->chunk_name[0] & 0x20))
+                if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
+                     PNG_HANDLE_CHUNK_ALWAYS)
+                   png_chunk_error(png_ptr, "unknown critical chunk");
+          }
+             png_set_unknown_chunks(png_ptr, info_ptr, &chunk, 1);
+       }
+       else
+#endif
+          png_set_unknown_chunks(png_ptr, info_ptr, &chunk, 1);
+       png_free(png_ptr, chunk.data);
+   }
+   else
+#endif
+      skip=length;
+   png_push_crc_skip(png_ptr, skip);
+}
+
+void /* PRIVATE */
+png_push_have_info(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr->info_fn != NULL)
+      (*(png_ptr->info_fn))(png_ptr, info_ptr);
+}
+
+void /* PRIVATE */
+png_push_have_end(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr->end_fn != NULL)
+      (*(png_ptr->end_fn))(png_ptr, info_ptr);
+}
+
+void /* PRIVATE */
+png_push_have_row(png_structp png_ptr, png_bytep row)
+{
+   if (png_ptr->row_fn != NULL)
+      (*(png_ptr->row_fn))(png_ptr, row, png_ptr->row_number,
+         (int)png_ptr->pass);
+}
+
+void PNGAPI
+png_progressive_combine_row (png_structp png_ptr,
+   png_bytep old_row, png_bytep new_row)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   const int FARDATA png_pass_dsp_mask[7] =
+      {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
+#endif
+   if (new_row != NULL)    /* new_row must == png_ptr->row_buf here. */
+      png_combine_row(png_ptr, old_row, png_pass_dsp_mask[png_ptr->pass]);
+}
+
+void PNGAPI
+png_set_progressive_read_fn(png_structp png_ptr, png_voidp progressive_ptr,
+   png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
+   png_progressive_end_ptr end_fn)
+{
+   png_ptr->info_fn = info_fn;
+   png_ptr->row_fn = row_fn;
+   png_ptr->end_fn = end_fn;
+
+   png_set_read_fn(png_ptr, progressive_ptr, png_push_fill_buffer);
+}
+
+png_voidp PNGAPI
+png_get_progressive_ptr(png_structp png_ptr)
+{
+   return png_ptr->io_ptr;
+}
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
diff --git a/gs/libpng/pngread.c b/gs/libpng/pngread.c
new file mode 100644
index 000000000..5924333df
--- /dev/null
+++ b/gs/libpng/pngread.c
@@ -0,0 +1,1456 @@
+
+/* pngread.c - read a PNG file
+ *
+ * libpng 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file contains routines that an application calls directly to
+ * read a PNG file or stream.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+/* Create a PNG structure for reading, and allocate any memory needed. */
+png_structp PNGAPI
+png_create_read_struct(png_const_charp user_png_ver, png_voidp error_ptr,
+   png_error_ptr error_fn, png_error_ptr warn_fn)
+{
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn,
+      warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL));
+}
+
+/* Alternate create PNG structure for reading, and allocate any memory needed. */
+png_structp PNGAPI
+png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
+   png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
+   png_malloc_ptr malloc_fn, png_free_ptr free_fn)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+   png_structp png_ptr;
+
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+   jmp_buf jmpbuf;
+#endif
+#endif
+
+   int i;
+
+   png_debug(1, "in png_create_read_struct\n");
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
+      (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);
+#else
+   png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
+#endif
+   if (png_ptr == NULL)
+      return (NULL);
+
+#if !defined(PNG_1_0_X)
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+   png_init_mmx_flags(png_ptr);   /* 1.2.0 addition */
+#endif
+#endif /* PNG_1_0_X */
+
+   /* added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+   png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
+   png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+   if (setjmp(jmpbuf))
+#else
+   if (setjmp(png_ptr->jmpbuf))
+#endif
+   {
+      png_free(png_ptr, png_ptr->zbuf);
+      png_ptr->zbuf=NULL;
+#ifdef PNG_USER_MEM_SUPPORTED
+      png_destroy_struct_2((png_voidp)png_ptr, 
+         (png_free_ptr)free_fn, (png_voidp)mem_ptr);
+#else
+      png_destroy_struct((png_voidp)png_ptr);
+#endif
+      return (NULL);
+   }
+#ifdef USE_FAR_KEYWORD
+   png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
+#endif
+#endif
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
+#endif
+
+   png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
+
+   i=0;
+   do
+   {
+     if(user_png_ver[i] != png_libpng_ver[i])
+        png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+   } while (png_libpng_ver[i++]);
+
+   if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
+   {
+     /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
+      * we must recompile any applications that use any older library version.
+      * For versions after libpng 1.0, we will be compatible, so we need
+      * only check the first digit.
+      */
+     if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
+         (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
+         (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
+     {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+        char msg[80];
+        if (user_png_ver)
+        {
+          sprintf(msg, "Application was compiled with png.h from libpng-%.20s",
+             user_png_ver);
+          png_warning(png_ptr, msg);
+        }
+        sprintf(msg, "Application  is  running with png.c from libpng-%.20s",
+           png_libpng_ver);
+        png_warning(png_ptr, msg);
+#endif
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+        png_ptr->flags=0;
+#endif
+        png_error(png_ptr,
+           "Incompatible libpng version in application and library");
+     }
+   }
+
+   /* initialize zbuf - compression buffer */
+   png_ptr->zbuf_size = PNG_ZBUF_SIZE;
+   png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+     (png_uint_32)png_ptr->zbuf_size);
+   png_ptr->zstream.zalloc = png_zalloc;
+   png_ptr->zstream.zfree = png_zfree;
+   png_ptr->zstream.opaque = (voidpf)png_ptr;
+
+   switch (inflateInit(&png_ptr->zstream))
+   {
+     case Z_OK: /* Do nothing */ break;
+     case Z_MEM_ERROR:
+     case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break;
+     case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break;
+     default: png_error(png_ptr, "Unknown zlib error");
+   }
+
+   png_ptr->zstream.next_out = png_ptr->zbuf;
+   png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+
+   png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
+
+#ifdef PNG_SETJMP_SUPPORTED
+/* Applications that neglect to set up their own setjmp() and then encounter
+   a png_error() will longjmp here.  Since the jmpbuf is then meaningless we
+   abort instead of returning. */
+#ifdef USE_FAR_KEYWORD
+   if (setjmp(jmpbuf))
+      PNG_ABORT();
+   png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
+#else
+   if (setjmp(png_ptr->jmpbuf))
+      PNG_ABORT();
+#endif
+#endif
+   return (png_ptr);
+}
+
+/* Initialize PNG structure for reading, and allocate any memory needed.
+   This interface is deprecated in favour of the png_create_read_struct(),
+   and it will eventually disappear. */
+#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
+#undef png_read_init
+void PNGAPI
+png_read_init(png_structp png_ptr)
+{
+   /* We only come here via pre-1.0.7-compiled applications */
+   png_read_init_2(png_ptr, "1.0.6 or earlier", 0, 0);
+}
+#endif
+
+void PNGAPI
+png_read_init_2(png_structp png_ptr, png_const_charp user_png_ver,
+   png_size_t png_struct_size, png_size_t png_info_size)
+{
+   /* We only come here via pre-1.0.12-compiled applications */
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+   if(png_sizeof(png_struct) > png_struct_size || 
+      png_sizeof(png_info) > png_info_size)
+   {
+      char msg[80];
+      png_ptr->warning_fn=NULL;
+      if (user_png_ver)
+      {
+        sprintf(msg, "Application was compiled with png.h from libpng-%.20s",
+           user_png_ver);
+        png_warning(png_ptr, msg);
+      }
+      sprintf(msg, "Application  is  running with png.c from libpng-%.20s",
+         png_libpng_ver);
+      png_warning(png_ptr, msg);
+   }
+#endif
+   if(png_sizeof(png_struct) > png_struct_size)
+     {
+       png_ptr->error_fn=NULL;
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+       png_ptr->flags=0;
+#endif
+       png_error(png_ptr,
+       "The png struct allocated by the application for reading is too small.");
+     }
+   if(png_sizeof(png_info) > png_info_size)
+     {
+       png_ptr->error_fn=NULL;
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+       png_ptr->flags=0;
+#endif
+       png_error(png_ptr,
+         "The info struct allocated by application for reading is too small.");
+     }
+   png_read_init_3(&png_ptr, user_png_ver, png_struct_size);
+}
+
+void PNGAPI
+png_read_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
+   png_size_t png_struct_size)
+{
+#ifdef PNG_SETJMP_SUPPORTED
+   jmp_buf tmp_jmp;  /* to save current jump buffer */
+#endif
+
+   int i=0;
+
+   png_structp png_ptr=*ptr_ptr;
+
+   do
+   {
+     if(user_png_ver[i] != png_libpng_ver[i])
+     {
+#ifdef PNG_LEGACY_SUPPORTED
+       png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+#else
+       png_ptr->warning_fn=NULL;
+       png_warning(png_ptr,
+        "Application uses deprecated png_read_init() and should be recompiled.");
+       break;
+#endif
+     }
+   } while (png_libpng_ver[i++]);
+
+   png_debug(1, "in png_read_init_3\n");
+
+#ifdef PNG_SETJMP_SUPPORTED
+   /* save jump buffer and error functions */
+   png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
+#endif
+
+   if(png_sizeof(png_struct) > png_struct_size)
+     {
+       png_destroy_struct(png_ptr);
+       *ptr_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
+       png_ptr = *ptr_ptr;
+     }
+
+   /* reset all variables to 0 */
+   png_memset(png_ptr, 0, png_sizeof (png_struct));
+
+#ifdef PNG_SETJMP_SUPPORTED
+   /* restore jump buffer */
+   png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
+#endif
+
+   /* added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+   png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
+   png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
+#endif
+
+   /* initialize zbuf - compression buffer */
+   png_ptr->zbuf_size = PNG_ZBUF_SIZE;
+   png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+     (png_uint_32)png_ptr->zbuf_size);
+   png_ptr->zstream.zalloc = png_zalloc;
+   png_ptr->zstream.zfree = png_zfree;
+   png_ptr->zstream.opaque = (voidpf)png_ptr;
+
+   switch (inflateInit(&png_ptr->zstream))
+   {
+     case Z_OK: /* Do nothing */ break;
+     case Z_MEM_ERROR:
+     case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break;
+     case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break;
+     default: png_error(png_ptr, "Unknown zlib error");
+   }
+
+   png_ptr->zstream.next_out = png_ptr->zbuf;
+   png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+
+   png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
+}
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* Read the information before the actual image data.  This has been
+ * changed in v0.90 to allow reading a file that already has the magic
+ * bytes read from the stream.  You can tell libpng how many bytes have
+ * been read from the beginning of the stream (up to the maximum of 8)
+ * via png_set_sig_bytes(), and we will only check the remaining bytes
+ * here.  The application can then have access to the signature bytes we
+ * read if it is determined that this isn't a valid PNG file.
+ */
+void PNGAPI
+png_read_info(png_structp png_ptr, png_infop info_ptr)
+{
+   png_debug(1, "in png_read_info\n");
+   /* If we haven't checked all of the PNG signature bytes, do so now. */
+   if (png_ptr->sig_bytes < 8)
+   {
+      png_size_t num_checked = png_ptr->sig_bytes,
+                 num_to_check = 8 - num_checked;
+
+      png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check);
+      png_ptr->sig_bytes = 8;
+
+      if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
+      {
+         if (num_checked < 4 &&
+             png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
+            png_error(png_ptr, "Not a PNG file");
+         else
+            png_error(png_ptr, "PNG file corrupted by ASCII conversion");
+      }
+      if (num_checked < 3)
+         png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
+   }
+
+   for(;;)
+   {
+#ifdef PNG_USE_LOCAL_ARRAYS
+      PNG_IHDR;
+      PNG_IDAT;
+      PNG_IEND;
+      PNG_PLTE;
+#if defined(PNG_READ_bKGD_SUPPORTED)
+      PNG_bKGD;
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+      PNG_cHRM;
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+      PNG_gAMA;
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+      PNG_hIST;
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+      PNG_iCCP;
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+      PNG_iTXt;
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+      PNG_oFFs;
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+      PNG_pCAL;
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+      PNG_pHYs;
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+      PNG_sBIT;
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+      PNG_sCAL;
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+      PNG_sPLT;
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+      PNG_sRGB;
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+      PNG_tEXt;
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+      PNG_tIME;
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+      PNG_tRNS;
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+      PNG_zTXt;
+#endif
+#endif /* PNG_USE_LOCAL_ARRAYS */
+      png_byte chunk_length[4];
+      png_uint_32 length;
+
+      png_read_data(png_ptr, chunk_length, 4);
+      length = png_get_uint_31(png_ptr,chunk_length);
+
+      png_reset_crc(png_ptr);
+      png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+
+      png_debug2(0, "Reading %s chunk, length=%lu.\n", png_ptr->chunk_name,
+         length);
+
+      /* This should be a binary subdivision search or a hash for
+       * matching the chunk name rather than a linear search.
+       */
+      if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
+         png_handle_IHDR(png_ptr, info_ptr, length);
+      else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
+         png_handle_IEND(png_ptr, info_ptr, length);
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+      else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
+      {
+         if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+            png_ptr->mode |= PNG_HAVE_IDAT;
+         png_handle_unknown(png_ptr, info_ptr, length);
+         if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+            png_ptr->mode |= PNG_HAVE_PLTE;
+         else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+         {
+            if (!(png_ptr->mode & PNG_HAVE_IHDR))
+               png_error(png_ptr, "Missing IHDR before IDAT");
+            else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+                     !(png_ptr->mode & PNG_HAVE_PLTE))
+               png_error(png_ptr, "Missing PLTE before IDAT");
+            break;
+         }
+      }
+#endif
+      else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+         png_handle_PLTE(png_ptr, info_ptr, length);
+      else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+      {
+         if (!(png_ptr->mode & PNG_HAVE_IHDR))
+            png_error(png_ptr, "Missing IHDR before IDAT");
+         else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+                  !(png_ptr->mode & PNG_HAVE_PLTE))
+            png_error(png_ptr, "Missing PLTE before IDAT");
+
+         png_ptr->idat_size = length;
+         png_ptr->mode |= PNG_HAVE_IDAT;
+         break;
+      }
+#if defined(PNG_READ_bKGD_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
+         png_handle_bKGD(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
+         png_handle_cHRM(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
+         png_handle_gAMA(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
+         png_handle_hIST(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
+         png_handle_oFFs(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
+         png_handle_pCAL(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
+         png_handle_sCAL(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
+         png_handle_pHYs(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
+         png_handle_sBIT(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
+         png_handle_sRGB(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
+         png_handle_iCCP(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
+         png_handle_sPLT(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
+         png_handle_tEXt(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
+         png_handle_tIME(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
+         png_handle_tRNS(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
+         png_handle_zTXt(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
+         png_handle_iTXt(png_ptr, info_ptr, length);
+#endif
+      else
+         png_handle_unknown(png_ptr, info_ptr, length);
+   }
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+/* optional call to update the users info_ptr structure */
+void PNGAPI
+png_read_update_info(png_structp png_ptr, png_infop info_ptr)
+{
+   png_debug(1, "in png_read_update_info\n");
+   if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+      png_read_start_row(png_ptr);
+   else
+      png_warning(png_ptr,
+      "Ignoring extra png_read_update_info() call; row buffer not reallocated");
+   png_read_transform_info(png_ptr, info_ptr);
+}
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* Initialize palette, background, etc, after transformations
+ * are set, but before any reading takes place.  This allows
+ * the user to obtain a gamma-corrected palette, for example.
+ * If the user doesn't call this, we will do it ourselves.
+ */
+void PNGAPI
+png_start_read_image(png_structp png_ptr)
+{
+   png_debug(1, "in png_start_read_image\n");
+   if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+      png_read_start_row(png_ptr);
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+void PNGAPI
+png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_IDAT;
+   const int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
+   const int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
+#endif
+   int ret;
+   png_debug2(1, "in png_read_row (row %lu, pass %d)\n",
+      png_ptr->row_number, png_ptr->pass);
+   if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+      png_read_start_row(png_ptr);
+   if (png_ptr->row_number == 0 && png_ptr->pass == 0)
+   {
+   /* check for transforms that have been set but were defined out */
+#if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED)
+   if (png_ptr->transformations & PNG_INVERT_MONO)
+      png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED)
+   if (png_ptr->transformations & PNG_FILLER)
+      png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && !defined(PNG_READ_PACKSWAP_SUPPORTED)
+   if (png_ptr->transformations & PNG_PACKSWAP)
+      png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED)
+   if (png_ptr->transformations & PNG_PACK)
+      png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED)
+   if (png_ptr->transformations & PNG_SHIFT)
+      png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED)
+   if (png_ptr->transformations & PNG_BGR)
+      png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined.");
+#endif
+#if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED)
+   if (png_ptr->transformations & PNG_SWAP_BYTES)
+      png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined.");
+#endif
+   }
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+   /* if interlaced and we do not need a new row, combine row and return */
+   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+   {
+      switch (png_ptr->pass)
+      {
+         case 0:
+            if (png_ptr->row_number & 0x07)
+            {
+               if (dsp_row != NULL)
+                  png_combine_row(png_ptr, dsp_row,
+                     png_pass_dsp_mask[png_ptr->pass]);
+               png_read_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 1:
+            if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
+            {
+               if (dsp_row != NULL)
+                  png_combine_row(png_ptr, dsp_row,
+                     png_pass_dsp_mask[png_ptr->pass]);
+               png_read_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 2:
+            if ((png_ptr->row_number & 0x07) != 4)
+            {
+               if (dsp_row != NULL && (png_ptr->row_number & 4))
+                  png_combine_row(png_ptr, dsp_row,
+                     png_pass_dsp_mask[png_ptr->pass]);
+               png_read_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 3:
+            if ((png_ptr->row_number & 3) || png_ptr->width < 3)
+            {
+               if (dsp_row != NULL)
+                  png_combine_row(png_ptr, dsp_row,
+                     png_pass_dsp_mask[png_ptr->pass]);
+               png_read_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 4:
+            if ((png_ptr->row_number & 3) != 2)
+            {
+               if (dsp_row != NULL && (png_ptr->row_number & 2))
+                  png_combine_row(png_ptr, dsp_row,
+                     png_pass_dsp_mask[png_ptr->pass]);
+               png_read_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 5:
+            if ((png_ptr->row_number & 1) || png_ptr->width < 2)
+            {
+               if (dsp_row != NULL)
+                  png_combine_row(png_ptr, dsp_row,
+                     png_pass_dsp_mask[png_ptr->pass]);
+               png_read_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 6:
+            if (!(png_ptr->row_number & 1))
+            {
+               png_read_finish_row(png_ptr);
+               return;
+            }
+            break;
+      }
+   }
+#endif
+
+   if (!(png_ptr->mode & PNG_HAVE_IDAT))
+      png_error(png_ptr, "Invalid attempt to read row data");
+
+   png_ptr->zstream.next_out = png_ptr->row_buf;
+   png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
+   do
+   {
+      if (!(png_ptr->zstream.avail_in))
+      {
+         while (!png_ptr->idat_size)
+         {
+            png_byte chunk_length[4];
+
+            png_crc_finish(png_ptr, 0);
+
+            png_read_data(png_ptr, chunk_length, 4);
+            png_ptr->idat_size = png_get_uint_31(png_ptr,chunk_length);
+
+            png_reset_crc(png_ptr);
+            png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+            if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+               png_error(png_ptr, "Not enough image data");
+         }
+         png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;
+         png_ptr->zstream.next_in = png_ptr->zbuf;
+         if (png_ptr->zbuf_size > png_ptr->idat_size)
+            png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
+         png_crc_read(png_ptr, png_ptr->zbuf,
+            (png_size_t)png_ptr->zstream.avail_in);
+         png_ptr->idat_size -= png_ptr->zstream.avail_in;
+      }
+      ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+      if (ret == Z_STREAM_END)
+      {
+         if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in ||
+            png_ptr->idat_size)
+            png_error(png_ptr, "Extra compressed data");
+         png_ptr->mode |= PNG_AFTER_IDAT;
+         png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
+         break;
+      }
+      if (ret != Z_OK)
+         png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
+                   "Decompression error");
+
+   } while (png_ptr->zstream.avail_out);
+
+   png_ptr->row_info.color_type = png_ptr->color_type;
+   png_ptr->row_info.width = png_ptr->iwidth;
+   png_ptr->row_info.channels = png_ptr->channels;
+   png_ptr->row_info.bit_depth = png_ptr->bit_depth;
+   png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
+   png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
+       png_ptr->row_info.width);
+
+   if(png_ptr->row_buf[0])
+   png_read_filter_row(png_ptr, &(png_ptr->row_info),
+      png_ptr->row_buf + 1, png_ptr->prev_row + 1,
+      (int)(png_ptr->row_buf[0]));
+
+   png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
+      png_ptr->rowbytes + 1);
+   
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+   if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+      (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
+   {
+      /* Intrapixel differencing */
+      png_do_read_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1);
+   }
+#endif
+
+
+   if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
+      png_do_read_transformations(png_ptr);
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+   /* blow up interlaced rows to full size */
+   if (png_ptr->interlaced &&
+      (png_ptr->transformations & PNG_INTERLACE))
+   {
+      if (png_ptr->pass < 6)
+/*       old interface (pre-1.0.9):
+         png_do_read_interlace(&(png_ptr->row_info),
+            png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
+ */
+         png_do_read_interlace(png_ptr);
+
+      if (dsp_row != NULL)
+         png_combine_row(png_ptr, dsp_row,
+            png_pass_dsp_mask[png_ptr->pass]);
+      if (row != NULL)
+         png_combine_row(png_ptr, row,
+            png_pass_mask[png_ptr->pass]);
+   }
+   else
+#endif
+   {
+      if (row != NULL)
+         png_combine_row(png_ptr, row, 0xff);
+      if (dsp_row != NULL)
+         png_combine_row(png_ptr, dsp_row, 0xff);
+   }
+   png_read_finish_row(png_ptr);
+
+   if (png_ptr->read_row_fn != NULL)
+      (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* Read one or more rows of image data.  If the image is interlaced,
+ * and png_set_interlace_handling() has been called, the rows need to
+ * contain the contents of the rows from the previous pass.  If the
+ * image has alpha or transparency, and png_handle_alpha()[*] has been
+ * called, the rows contents must be initialized to the contents of the
+ * screen.
+ *
+ * "row" holds the actual image, and pixels are placed in it
+ * as they arrive.  If the image is displayed after each pass, it will
+ * appear to "sparkle" in.  "display_row" can be used to display a
+ * "chunky" progressive image, with finer detail added as it becomes
+ * available.  If you do not want this "chunky" display, you may pass
+ * NULL for display_row.  If you do not want the sparkle display, and
+ * you have not called png_handle_alpha(), you may pass NULL for rows.
+ * If you have called png_handle_alpha(), and the image has either an
+ * alpha channel or a transparency chunk, you must provide a buffer for
+ * rows.  In this case, you do not have to provide a display_row buffer
+ * also, but you may.  If the image is not interlaced, or if you have
+ * not called png_set_interlace_handling(), the display_row buffer will
+ * be ignored, so pass NULL to it.
+ *
+ * [*] png_handle_alpha() does not exist yet, as of libpng version 1.2.8
+ */
+
+void PNGAPI
+png_read_rows(png_structp png_ptr, png_bytepp row,
+   png_bytepp display_row, png_uint_32 num_rows)
+{
+   png_uint_32 i;
+   png_bytepp rp;
+   png_bytepp dp;
+
+   png_debug(1, "in png_read_rows\n");
+   rp = row;
+   dp = display_row;
+   if (rp != NULL && dp != NULL)
+      for (i = 0; i < num_rows; i++)
+      {
+         png_bytep rptr = *rp++;
+         png_bytep dptr = *dp++;
+
+         png_read_row(png_ptr, rptr, dptr);
+      }
+   else if(rp != NULL)
+      for (i = 0; i < num_rows; i++)
+      {
+         png_bytep rptr = *rp;
+         png_read_row(png_ptr, rptr, png_bytep_NULL);
+         rp++;
+      }
+   else if(dp != NULL)
+      for (i = 0; i < num_rows; i++)
+      {
+         png_bytep dptr = *dp;
+         png_read_row(png_ptr, png_bytep_NULL, dptr);
+         dp++;
+      }
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* Read the entire image.  If the image has an alpha channel or a tRNS
+ * chunk, and you have called png_handle_alpha()[*], you will need to
+ * initialize the image to the current image that PNG will be overlaying.
+ * We set the num_rows again here, in case it was incorrectly set in
+ * png_read_start_row() by a call to png_read_update_info() or
+ * png_start_read_image() if png_set_interlace_handling() wasn't called
+ * prior to either of these functions like it should have been.  You can
+ * only call this function once.  If you desire to have an image for
+ * each pass of a interlaced image, use png_read_rows() instead.
+ *
+ * [*] png_handle_alpha() does not exist yet, as of libpng version 1.2.8
+ */
+void PNGAPI
+png_read_image(png_structp png_ptr, png_bytepp image)
+{
+   png_uint_32 i,image_height;
+   int pass, j;
+   png_bytepp rp;
+
+   png_debug(1, "in png_read_image\n");
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+   pass = png_set_interlace_handling(png_ptr);
+#else
+   if (png_ptr->interlaced)
+      png_error(png_ptr,
+        "Cannot read interlaced image -- interlace handler disabled.");
+   pass = 1;
+#endif
+
+
+   image_height=png_ptr->height;
+   png_ptr->num_rows = image_height; /* Make sure this is set correctly */
+
+   for (j = 0; j < pass; j++)
+   {
+      rp = image;
+      for (i = 0; i < image_height; i++)
+      {
+         png_read_row(png_ptr, *rp, png_bytep_NULL);
+         rp++;
+      }
+   }
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+/* Read the end of the PNG file.  Will not read past the end of the
+ * file, will verify the end is accurate, and will read any comments
+ * or time information at the end of the file, if info is not NULL.
+ */
+void PNGAPI
+png_read_end(png_structp png_ptr, png_infop info_ptr)
+{
+   png_byte chunk_length[4];
+   png_uint_32 length;
+
+   png_debug(1, "in png_read_end\n");
+   png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
+
+   do
+   {
+#ifdef PNG_USE_LOCAL_ARRAYS
+      PNG_IHDR;
+      PNG_IDAT;
+      PNG_IEND;
+      PNG_PLTE;
+#if defined(PNG_READ_bKGD_SUPPORTED)
+      PNG_bKGD;
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+      PNG_cHRM;
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+      PNG_gAMA;
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+      PNG_hIST;
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+      PNG_iCCP;
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+      PNG_iTXt;
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+      PNG_oFFs;
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+      PNG_pCAL;
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+      PNG_pHYs;
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+      PNG_sBIT;
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+      PNG_sCAL;
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+      PNG_sPLT;
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+      PNG_sRGB;
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+      PNG_tEXt;
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+      PNG_tIME;
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+      PNG_tRNS;
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+      PNG_zTXt;
+#endif
+#endif /* PNG_USE_LOCAL_ARRAYS */
+
+      png_read_data(png_ptr, chunk_length, 4);
+      length = png_get_uint_31(png_ptr,chunk_length);
+
+      png_reset_crc(png_ptr);
+      png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+
+      png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name);
+
+      if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
+         png_handle_IHDR(png_ptr, info_ptr, length);
+      else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
+         png_handle_IEND(png_ptr, info_ptr, length);
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+      else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
+      {
+         if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+         {
+            if (length > 0 || png_ptr->mode & PNG_AFTER_IDAT)
+               png_error(png_ptr, "Too many IDAT's found");
+         }
+         else
+            png_ptr->mode |= PNG_AFTER_IDAT;
+         png_handle_unknown(png_ptr, info_ptr, length);
+         if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+            png_ptr->mode |= PNG_HAVE_PLTE;
+      }
+#endif
+      else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+      {
+         /* Zero length IDATs are legal after the last IDAT has been
+          * read, but not after other chunks have been read.
+          */
+         if (length > 0 || png_ptr->mode & PNG_AFTER_IDAT)
+            png_error(png_ptr, "Too many IDAT's found");
+         png_crc_finish(png_ptr, length);
+      }
+      else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+         png_handle_PLTE(png_ptr, info_ptr, length);
+#if defined(PNG_READ_bKGD_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
+         png_handle_bKGD(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
+         png_handle_cHRM(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
+         png_handle_gAMA(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
+         png_handle_hIST(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
+         png_handle_oFFs(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
+         png_handle_pCAL(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sCAL_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
+         png_handle_sCAL(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
+         png_handle_pHYs(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
+         png_handle_sBIT(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
+         png_handle_sRGB(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
+         png_handle_iCCP(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
+         png_handle_sPLT(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
+         png_handle_tEXt(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
+         png_handle_tIME(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
+         png_handle_tRNS(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
+         png_handle_zTXt(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_iTXt_SUPPORTED)
+      else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
+         png_handle_iTXt(png_ptr, info_ptr, length);
+#endif
+      else
+         png_handle_unknown(png_ptr, info_ptr, length);
+   } while (!(png_ptr->mode & PNG_HAVE_IEND));
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+/* free all memory used by the read */
+void PNGAPI
+png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr,
+   png_infopp end_info_ptr_ptr)
+{
+   png_structp png_ptr = NULL;
+   png_infop info_ptr = NULL, end_info_ptr = NULL;
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_free_ptr free_fn;
+   png_voidp mem_ptr;
+#endif
+
+   png_debug(1, "in png_destroy_read_struct\n");
+   if (png_ptr_ptr != NULL)
+      png_ptr = *png_ptr_ptr;
+
+   if (info_ptr_ptr != NULL)
+      info_ptr = *info_ptr_ptr;
+
+   if (end_info_ptr_ptr != NULL)
+      end_info_ptr = *end_info_ptr_ptr;
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   free_fn = png_ptr->free_fn;
+   mem_ptr = png_ptr->mem_ptr;
+#endif
+
+   png_read_destroy(png_ptr, info_ptr, end_info_ptr);
+
+   if (info_ptr != NULL)
+   {
+#if defined(PNG_TEXT_SUPPORTED)
+      png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, -1);
+#endif
+
+#ifdef PNG_USER_MEM_SUPPORTED
+      png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,
+          (png_voidp)mem_ptr);
+#else
+      png_destroy_struct((png_voidp)info_ptr);
+#endif
+      *info_ptr_ptr = NULL;
+   }
+
+   if (end_info_ptr != NULL)
+   {
+#if defined(PNG_READ_TEXT_SUPPORTED)
+      png_free_data(png_ptr, end_info_ptr, PNG_FREE_TEXT, -1);
+#endif
+#ifdef PNG_USER_MEM_SUPPORTED
+      png_destroy_struct_2((png_voidp)end_info_ptr, (png_free_ptr)free_fn,
+         (png_voidp)mem_ptr);
+#else
+      png_destroy_struct((png_voidp)end_info_ptr);
+#endif
+      *end_info_ptr_ptr = NULL;
+   }
+
+   if (png_ptr != NULL)
+   {
+#ifdef PNG_USER_MEM_SUPPORTED
+      png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,
+          (png_voidp)mem_ptr);
+#else
+      png_destroy_struct((png_voidp)png_ptr);
+#endif
+      *png_ptr_ptr = NULL;
+   }
+}
+
+/* free all memory used by the read (old method) */
+void /* PRIVATE */
+png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr)
+{
+#ifdef PNG_SETJMP_SUPPORTED
+   jmp_buf tmp_jmp;
+#endif
+   png_error_ptr error_fn;
+   png_error_ptr warning_fn;
+   png_voidp error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_free_ptr free_fn;
+#endif
+
+   png_debug(1, "in png_read_destroy\n");
+   if (info_ptr != NULL)
+      png_info_destroy(png_ptr, info_ptr);
+
+   if (end_info_ptr != NULL)
+      png_info_destroy(png_ptr, end_info_ptr);
+
+   png_free(png_ptr, png_ptr->zbuf);
+   png_free(png_ptr, png_ptr->big_row_buf);
+   png_free(png_ptr, png_ptr->prev_row);
+#if defined(PNG_READ_DITHER_SUPPORTED)
+   png_free(png_ptr, png_ptr->palette_lookup);
+   png_free(png_ptr, png_ptr->dither_index);
+#endif
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+   png_free(png_ptr, png_ptr->gamma_table);
+#endif
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+   png_free(png_ptr, png_ptr->gamma_from_1);
+   png_free(png_ptr, png_ptr->gamma_to_1);
+#endif
+#ifdef PNG_FREE_ME_SUPPORTED
+   if (png_ptr->free_me & PNG_FREE_PLTE)
+      png_zfree(png_ptr, png_ptr->palette);
+   png_ptr->free_me &= ~PNG_FREE_PLTE;
+#else
+   if (png_ptr->flags & PNG_FLAG_FREE_PLTE)
+      png_zfree(png_ptr, png_ptr->palette);
+   png_ptr->flags &= ~PNG_FLAG_FREE_PLTE;
+#endif
+#if defined(PNG_tRNS_SUPPORTED) || \
+    defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+#ifdef PNG_FREE_ME_SUPPORTED
+   if (png_ptr->free_me & PNG_FREE_TRNS)
+      png_free(png_ptr, png_ptr->trans);
+   png_ptr->free_me &= ~PNG_FREE_TRNS;
+#else
+   if (png_ptr->flags & PNG_FLAG_FREE_TRNS)
+      png_free(png_ptr, png_ptr->trans);
+   png_ptr->flags &= ~PNG_FLAG_FREE_TRNS;
+#endif
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+#ifdef PNG_FREE_ME_SUPPORTED
+   if (png_ptr->free_me & PNG_FREE_HIST)
+      png_free(png_ptr, png_ptr->hist);
+   png_ptr->free_me &= ~PNG_FREE_HIST;
+#else
+   if (png_ptr->flags & PNG_FLAG_FREE_HIST)
+      png_free(png_ptr, png_ptr->hist);
+   png_ptr->flags &= ~PNG_FLAG_FREE_HIST;
+#endif
+#endif
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+   if (png_ptr->gamma_16_table != NULL)
+   {
+      int i;
+      int istop = (1 << (8 - png_ptr->gamma_shift));
+      for (i = 0; i < istop; i++)
+      {
+         png_free(png_ptr, png_ptr->gamma_16_table[i]);
+      }
+   png_free(png_ptr, png_ptr->gamma_16_table);
+   }
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+   if (png_ptr->gamma_16_from_1 != NULL)
+   {
+      int i;
+      int istop = (1 << (8 - png_ptr->gamma_shift));
+      for (i = 0; i < istop; i++)
+      {
+         png_free(png_ptr, png_ptr->gamma_16_from_1[i]);
+      }
+   png_free(png_ptr, png_ptr->gamma_16_from_1);
+   }
+   if (png_ptr->gamma_16_to_1 != NULL)
+   {
+      int i;
+      int istop = (1 << (8 - png_ptr->gamma_shift));
+      for (i = 0; i < istop; i++)
+      {
+         png_free(png_ptr, png_ptr->gamma_16_to_1[i]);
+      }
+   png_free(png_ptr, png_ptr->gamma_16_to_1);
+   }
+#endif
+#endif
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+   png_free(png_ptr, png_ptr->time_buffer);
+#endif
+
+   inflateEnd(&png_ptr->zstream);
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+   png_free(png_ptr, png_ptr->save_buffer);
+#endif
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+#ifdef PNG_TEXT_SUPPORTED
+   png_free(png_ptr, png_ptr->current_text);
+#endif /* PNG_TEXT_SUPPORTED */
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+   /* Save the important info out of the png_struct, in case it is
+    * being used again.
+    */
+#ifdef PNG_SETJMP_SUPPORTED
+   png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
+#endif
+
+   error_fn = png_ptr->error_fn;
+   warning_fn = png_ptr->warning_fn;
+   error_ptr = png_ptr->error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+   free_fn = png_ptr->free_fn;
+#endif
+
+   png_memset(png_ptr, 0, png_sizeof (png_struct));
+
+   png_ptr->error_fn = error_fn;
+   png_ptr->warning_fn = warning_fn;
+   png_ptr->error_ptr = error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_ptr->free_fn = free_fn;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+   png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
+#endif
+
+}
+
+void PNGAPI
+png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn)
+{
+   png_ptr->read_row_fn = read_row_fn;
+}
+
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+void PNGAPI
+png_read_png(png_structp png_ptr, png_infop info_ptr,
+                           int transforms,
+                           voidp params)
+{
+   int row;
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
+   /* invert the alpha channel from opacity to transparency
+    */
+   if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
+       png_set_invert_alpha(png_ptr);
+#endif
+
+   /* png_read_info() gives us all of the information from the
+    * PNG file before the first IDAT (image data chunk).
+    */
+   png_read_info(png_ptr, info_ptr);
+   if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep))
+      png_error(png_ptr,"Image is too high to process with png_read_png()");
+
+   /* -------------- image transformations start here ------------------- */
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+   /* tell libpng to strip 16 bit/color files down to 8 bits per color
+    */
+   if (transforms & PNG_TRANSFORM_STRIP_16)
+       png_set_strip_16(png_ptr);
+#endif
+
+#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+   /* Strip alpha bytes from the input data without combining with
+    * the background (not recommended).
+    */
+   if (transforms & PNG_TRANSFORM_STRIP_ALPHA)
+       png_set_strip_alpha(png_ptr);
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED)
+   /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single
+    * byte into separate bytes (useful for paletted and grayscale images).
+    */
+   if (transforms & PNG_TRANSFORM_PACKING)
+       png_set_packing(png_ptr);
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+   /* Change the order of packed pixels to least significant bit first
+    * (not useful if you are using png_set_packing).
+    */
+   if (transforms & PNG_TRANSFORM_PACKSWAP)
+       png_set_packswap(png_ptr);
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+   /* Expand paletted colors into true RGB triplets
+    * Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel
+    * Expand paletted or RGB images with transparency to full alpha
+    * channels so the data will be available as RGBA quartets.
+    */
+   if (transforms & PNG_TRANSFORM_EXPAND)
+       if ((png_ptr->bit_depth < 8) ||
+           (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ||
+           (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
+         png_set_expand(png_ptr);
+#endif
+
+   /* We don't handle background color or gamma transformation or dithering.
+    */
+
+#if defined(PNG_READ_INVERT_SUPPORTED)
+   /* invert monochrome files to have 0 as white and 1 as black
+    */
+   if (transforms & PNG_TRANSFORM_INVERT_MONO)
+       png_set_invert_mono(png_ptr);
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED)
+   /* If you want to shift the pixel values from the range [0,255] or
+    * [0,65535] to the original [0,7] or [0,31], or whatever range the
+    * colors were originally in:
+    */
+   if ((transforms & PNG_TRANSFORM_SHIFT)
+       && png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
+   {
+      png_color_8p sig_bit;
+
+      png_get_sBIT(png_ptr, info_ptr, &sig_bit);
+      png_set_shift(png_ptr, sig_bit);
+   }
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED)
+   /* flip the RGB pixels to BGR (or RGBA to BGRA)
+    */
+   if (transforms & PNG_TRANSFORM_BGR)
+       png_set_bgr(png_ptr);
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
+   /* swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR)
+    */
+   if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
+       png_set_swap_alpha(png_ptr);
+#endif
+
+#if defined(PNG_READ_SWAP_SUPPORTED)
+   /* swap bytes of 16 bit files to least significant byte first
+    */
+   if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
+       png_set_swap(png_ptr);
+#endif
+
+   /* We don't handle adding filler bytes */
+
+   /* Optional call to gamma correct and add the background to the palette
+    * and update info structure.  REQUIRED if you are expecting libpng to
+    * update the palette for you (i.e., you selected such a transform above).
+    */
+   png_read_update_info(png_ptr, info_ptr);
+
+   /* -------------- image transformations end here ------------------- */
+
+#ifdef PNG_FREE_ME_SUPPORTED
+   png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
+#endif
+   if(info_ptr->row_pointers == NULL)
+   {
+      info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr,
+         info_ptr->height * png_sizeof(png_bytep));
+#ifdef PNG_FREE_ME_SUPPORTED
+      info_ptr->free_me |= PNG_FREE_ROWS;
+#endif
+      for (row = 0; row < (int)info_ptr->height; row++)
+      {
+         info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr,
+            png_get_rowbytes(png_ptr, info_ptr));
+      }
+   }
+
+   png_read_image(png_ptr, info_ptr->row_pointers);
+   info_ptr->valid |= PNG_INFO_IDAT;
+
+   /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
+   png_read_end(png_ptr, info_ptr);
+
+   if(transforms == 0 || params == NULL)
+      /* quiet compiler warnings */ return;
+
+}
+#endif
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
diff --git a/gs/libpng/pngrio.c b/gs/libpng/pngrio.c
new file mode 100644
index 000000000..cae501a5c
--- /dev/null
+++ b/gs/libpng/pngrio.c
@@ -0,0 +1,161 @@
+
+/* pngrio.c - functions for data input
+ *
+ * libpng 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file provides a location for all input.  Users who need
+ * special handling are expected to write a function that has the same
+ * arguments as this and performs a similar function, but that possibly
+ * has a different input method.  Note that you shouldn't change this
+ * function, but rather write a replacement function and then make
+ * libpng use it at run time with png_set_read_fn(...).
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+/* Read the data from whatever input you are using.  The default routine
+   reads from a file pointer.  Note that this routine sometimes gets called
+   with very small lengths, so you should implement some kind of simple
+   buffering if you are using unbuffered reads.  This should never be asked
+   to read more then 64K on a 16 bit machine. */
+void /* PRIVATE */
+png_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   png_debug1(4,"reading %d bytes\n", (int)length);
+   if (png_ptr->read_data_fn != NULL)
+      (*(png_ptr->read_data_fn))(png_ptr, data, length);
+   else
+      png_error(png_ptr, "Call to NULL read function");
+}
+
+#if !defined(PNG_NO_STDIO)
+/* This is the function that does the actual reading of data.  If you are
+   not reading from a standard C stream, you should create a replacement
+   read_data function and use it at run time with png_set_read_fn(), rather
+   than changing the library. */
+#ifndef USE_FAR_KEYWORD
+void PNGAPI
+png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   png_size_t check;
+
+   /* fread() returns 0 on error, so it is OK to store this in a png_size_t
+    * instead of an int, which is what fread() actually returns.
+    */
+#if defined(_WIN32_WCE)
+   if ( !ReadFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) )
+      check = 0;
+#else
+   check = (png_size_t)fread(data, (png_size_t)1, length,
+      (png_FILE_p)png_ptr->io_ptr);
+#endif
+
+   if (check != length)
+      png_error(png_ptr, "Read Error");
+}
+#else
+/* this is the model-independent version. Since the standard I/O library
+   can't handle far buffers in the medium and small models, we have to copy
+   the data.
+*/
+
+#define NEAR_BUF_SIZE 1024
+#define MIN(a,b) (a <= b ? a : b)
+
+static void /* PRIVATE */
+png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   int check;
+   png_byte *n_data;
+   png_FILE_p io_ptr;
+
+   /* Check if data really is near. If so, use usual code. */
+   n_data = (png_byte *)CVT_PTR_NOCHECK(data);
+   io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr);
+   if ((png_bytep)n_data == data)
+   {
+#if defined(_WIN32_WCE)
+      if ( !ReadFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) )
+         check = 0;
+#else
+      check = fread(n_data, 1, length, io_ptr);
+#endif
+   }
+   else
+   {
+      png_byte buf[NEAR_BUF_SIZE];
+      png_size_t read, remaining, err;
+      check = 0;
+      remaining = length;
+      do
+      {
+         read = MIN(NEAR_BUF_SIZE, remaining);
+#if defined(_WIN32_WCE)
+         if ( !ReadFile((HANDLE)(io_ptr), buf, read, &err, NULL) )
+            err = 0;
+#else
+         err = fread(buf, (png_size_t)1, read, io_ptr);
+#endif
+         png_memcpy(data, buf, read); /* copy far buffer to near buffer */
+         if(err != read)
+            break;
+         else
+            check += err;
+         data += read;
+         remaining -= read;
+      }
+      while (remaining != 0);
+   }
+   if ((png_uint_32)check != (png_uint_32)length)
+      png_error(png_ptr, "read Error");
+}
+#endif
+#endif
+
+/* This function allows the application to supply a new input function
+   for libpng if standard C streams aren't being used.
+
+   This function takes as its arguments:
+   png_ptr      - pointer to a png input data structure
+   io_ptr       - pointer to user supplied structure containing info about
+                  the input functions.  May be NULL.
+   read_data_fn - pointer to a new input function that takes as its
+                  arguments a pointer to a png_struct, a pointer to
+                  a location where input data can be stored, and a 32-bit
+                  unsigned int that is the number of bytes to be read.
+                  To exit and output any fatal error messages the new write
+                  function should call png_error(png_ptr, "Error msg"). */
+void PNGAPI
+png_set_read_fn(png_structp png_ptr, png_voidp io_ptr,
+   png_rw_ptr read_data_fn)
+{
+   png_ptr->io_ptr = io_ptr;
+
+#if !defined(PNG_NO_STDIO)
+   if (read_data_fn != NULL)
+      png_ptr->read_data_fn = read_data_fn;
+   else
+      png_ptr->read_data_fn = png_default_read_data;
+#else
+   png_ptr->read_data_fn = read_data_fn;
+#endif
+
+   /* It is an error to write to a read device */
+   if (png_ptr->write_data_fn != NULL)
+   {
+      png_ptr->write_data_fn = NULL;
+      png_warning(png_ptr,
+         "It's an error to set both read_data_fn and write_data_fn in the ");
+      png_warning(png_ptr,
+         "same structure.  Resetting write_data_fn to NULL.");
+   }
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+   png_ptr->output_flush_fn = NULL;
+#endif
+}
diff --git a/gs/libpng/pngrtran.c b/gs/libpng/pngrtran.c
new file mode 100644
index 000000000..e1d6e3ce3
--- /dev/null
+++ b/gs/libpng/pngrtran.c
@@ -0,0 +1,4177 @@
+
+/* pngrtran.c - transforms the data in a row for PNG readers
+ *
+ * libpng version  1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file contains functions optionally called by an application
+ * in order to tell libpng how to handle data when reading a PNG.
+ * Transformations that are used in both reading and writing are
+ * in pngtrans.c.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+/* Set the action on getting a CRC error for an ancillary or critical chunk. */
+void PNGAPI
+png_set_crc_action(png_structp png_ptr, int crit_action, int ancil_action)
+{
+   png_debug(1, "in png_set_crc_action\n");
+   /* Tell libpng how we react to CRC errors in critical chunks */
+   switch (crit_action)
+   {
+      case PNG_CRC_NO_CHANGE:                        /* leave setting as is */
+         break;
+      case PNG_CRC_WARN_USE:                               /* warn/use data */
+         png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
+         png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE;
+         break;
+      case PNG_CRC_QUIET_USE:                             /* quiet/use data */
+         png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
+         png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE |
+                           PNG_FLAG_CRC_CRITICAL_IGNORE;
+         break;
+      case PNG_CRC_WARN_DISCARD:    /* not a valid action for critical data */
+         png_warning(png_ptr, "Can't discard critical data on CRC error.");
+      case PNG_CRC_ERROR_QUIT:                                /* error/quit */
+      case PNG_CRC_DEFAULT:
+      default:
+         png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
+         break;
+   }
+
+   switch (ancil_action)
+   {
+      case PNG_CRC_NO_CHANGE:                       /* leave setting as is */
+         break;
+      case PNG_CRC_WARN_USE:                              /* warn/use data */
+         png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
+         png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE;
+         break;
+      case PNG_CRC_QUIET_USE:                            /* quiet/use data */
+         png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
+         png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE |
+                           PNG_FLAG_CRC_ANCILLARY_NOWARN;
+         break;
+      case PNG_CRC_ERROR_QUIT:                               /* error/quit */
+         png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
+         png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_NOWARN;
+         break;
+      case PNG_CRC_WARN_DISCARD:                      /* warn/discard data */
+      case PNG_CRC_DEFAULT:
+      default:
+         png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
+         break;
+   }
+}
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \
+    defined(PNG_FLOATING_POINT_SUPPORTED)
+/* handle alpha and tRNS via a background color */
+void PNGAPI
+png_set_background(png_structp png_ptr,
+   png_color_16p background_color, int background_gamma_code,
+   int need_expand, double background_gamma)
+{
+   png_debug(1, "in png_set_background\n");
+   if (background_gamma_code == PNG_BACKGROUND_GAMMA_UNKNOWN)
+   {
+      png_warning(png_ptr, "Application must supply a known background gamma");
+      return;
+   }
+
+   png_ptr->transformations |= PNG_BACKGROUND;
+   png_memcpy(&(png_ptr->background), background_color,
+      png_sizeof(png_color_16));
+   png_ptr->background_gamma = (float)background_gamma;
+   png_ptr->background_gamma_type = (png_byte)(background_gamma_code);
+   png_ptr->transformations |= (need_expand ? PNG_BACKGROUND_EXPAND : 0);
+
+   /* Note:  if need_expand is set and color_type is either RGB or RGB_ALPHA
+    * (in which case need_expand is superfluous anyway), the background color
+    * might actually be gray yet not be flagged as such. This is not a problem
+    * for the current code, which uses PNG_BACKGROUND_IS_GRAY only to
+    * decide when to do the png_do_gray_to_rgb() transformation.
+    */
+   if ((need_expand && !(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) ||
+       (!need_expand && background_color->red == background_color->green &&
+        background_color->red == background_color->blue))
+      png_ptr->mode |= PNG_BACKGROUND_IS_GRAY;
+}
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+/* strip 16 bit depth files to 8 bit depth */
+void PNGAPI
+png_set_strip_16(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_strip_16\n");
+   png_ptr->transformations |= PNG_16_TO_8;
+}
+#endif
+
+#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+void PNGAPI
+png_set_strip_alpha(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_strip_alpha\n");
+   png_ptr->flags |= PNG_FLAG_STRIP_ALPHA;
+}
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+/* Dither file to 8 bit.  Supply a palette, the current number
+ * of elements in the palette, the maximum number of elements
+ * allowed, and a histogram if possible.  If the current number
+ * of colors is greater then the maximum number, the palette will be
+ * modified to fit in the maximum number.  "full_dither" indicates
+ * whether we need a dithering cube set up for RGB images, or if we
+ * simply are reducing the number of colors in a paletted image.
+ */
+
+typedef struct png_dsort_struct
+{
+   struct png_dsort_struct FAR * next;
+   png_byte left;
+   png_byte right;
+} png_dsort;
+typedef png_dsort FAR *       png_dsortp;
+typedef png_dsort FAR * FAR * png_dsortpp;
+
+void PNGAPI
+png_set_dither(png_structp png_ptr, png_colorp palette,
+   int num_palette, int maximum_colors, png_uint_16p histogram,
+   int full_dither)
+{
+   png_debug(1, "in png_set_dither\n");
+   png_ptr->transformations |= PNG_DITHER;
+
+   if (!full_dither)
+   {
+      int i;
+
+      png_ptr->dither_index = (png_bytep)png_malloc(png_ptr,
+         (png_uint_32)(num_palette * png_sizeof (png_byte)));
+      for (i = 0; i < num_palette; i++)
+         png_ptr->dither_index[i] = (png_byte)i;
+   }
+
+   if (num_palette > maximum_colors)
+   {
+      if (histogram != NULL)
+      {
+         /* This is easy enough, just throw out the least used colors.
+            Perhaps not the best solution, but good enough. */
+
+         int i;
+
+         /* initialize an array to sort colors */
+         png_ptr->dither_sort = (png_bytep)png_malloc(png_ptr,
+            (png_uint_32)(num_palette * png_sizeof (png_byte)));
+
+         /* initialize the dither_sort array */
+         for (i = 0; i < num_palette; i++)
+            png_ptr->dither_sort[i] = (png_byte)i;
+
+         /* Find the least used palette entries by starting a
+            bubble sort, and running it until we have sorted
+            out enough colors.  Note that we don't care about
+            sorting all the colors, just finding which are
+            least used. */
+
+         for (i = num_palette - 1; i >= maximum_colors; i--)
+         {
+            int done; /* to stop early if the list is pre-sorted */
+            int j;
+
+            done = 1;
+            for (j = 0; j < i; j++)
+            {
+               if (histogram[png_ptr->dither_sort[j]]
+                   < histogram[png_ptr->dither_sort[j + 1]])
+               {
+                  png_byte t;
+
+                  t = png_ptr->dither_sort[j];
+                  png_ptr->dither_sort[j] = png_ptr->dither_sort[j + 1];
+                  png_ptr->dither_sort[j + 1] = t;
+                  done = 0;
+               }
+            }
+            if (done)
+               break;
+         }
+
+         /* swap the palette around, and set up a table, if necessary */
+         if (full_dither)
+         {
+            int j = num_palette;
+
+            /* put all the useful colors within the max, but don't
+               move the others */
+            for (i = 0; i < maximum_colors; i++)
+            {
+               if ((int)png_ptr->dither_sort[i] >= maximum_colors)
+               {
+                  do
+                     j--;
+                  while ((int)png_ptr->dither_sort[j] >= maximum_colors);
+                  palette[i] = palette[j];
+               }
+            }
+         }
+         else
+         {
+            int j = num_palette;
+
+            /* move all the used colors inside the max limit, and
+               develop a translation table */
+            for (i = 0; i < maximum_colors; i++)
+            {
+               /* only move the colors we need to */
+               if ((int)png_ptr->dither_sort[i] >= maximum_colors)
+               {
+                  png_color tmp_color;
+
+                  do
+                     j--;
+                  while ((int)png_ptr->dither_sort[j] >= maximum_colors);
+
+                  tmp_color = palette[j];
+                  palette[j] = palette[i];
+                  palette[i] = tmp_color;
+                  /* indicate where the color went */
+                  png_ptr->dither_index[j] = (png_byte)i;
+                  png_ptr->dither_index[i] = (png_byte)j;
+               }
+            }
+
+            /* find closest color for those colors we are not using */
+            for (i = 0; i < num_palette; i++)
+            {
+               if ((int)png_ptr->dither_index[i] >= maximum_colors)
+               {
+                  int min_d, k, min_k, d_index;
+
+                  /* find the closest color to one we threw out */
+                  d_index = png_ptr->dither_index[i];
+                  min_d = PNG_COLOR_DIST(palette[d_index], palette[0]);
+                  for (k = 1, min_k = 0; k < maximum_colors; k++)
+                  {
+                     int d;
+
+                     d = PNG_COLOR_DIST(palette[d_index], palette[k]);
+
+                     if (d < min_d)
+                     {
+                        min_d = d;
+                        min_k = k;
+                     }
+                  }
+                  /* point to closest color */
+                  png_ptr->dither_index[i] = (png_byte)min_k;
+               }
+            }
+         }
+         png_free(png_ptr, png_ptr->dither_sort);
+         png_ptr->dither_sort=NULL;
+      }
+      else
+      {
+         /* This is much harder to do simply (and quickly).  Perhaps
+            we need to go through a median cut routine, but those
+            don't always behave themselves with only a few colors
+            as input.  So we will just find the closest two colors,
+            and throw out one of them (chosen somewhat randomly).
+            [We don't understand this at all, so if someone wants to
+             work on improving it, be our guest - AED, GRP]
+            */
+         int i;
+         int max_d;
+         int num_new_palette;
+         png_dsortp t;
+         png_dsortpp hash;
+
+         t=NULL;
+
+         /* initialize palette index arrays */
+         png_ptr->index_to_palette = (png_bytep)png_malloc(png_ptr,
+            (png_uint_32)(num_palette * png_sizeof (png_byte)));
+         png_ptr->palette_to_index = (png_bytep)png_malloc(png_ptr,
+            (png_uint_32)(num_palette * png_sizeof (png_byte)));
+
+         /* initialize the sort array */
+         for (i = 0; i < num_palette; i++)
+         {
+            png_ptr->index_to_palette[i] = (png_byte)i;
+            png_ptr->palette_to_index[i] = (png_byte)i;
+         }
+
+         hash = (png_dsortpp)png_malloc(png_ptr, (png_uint_32)(769 *
+            png_sizeof (png_dsortp)));
+         for (i = 0; i < 769; i++)
+            hash[i] = NULL;
+/*         png_memset(hash, 0, 769 * png_sizeof (png_dsortp)); */
+
+         num_new_palette = num_palette;
+
+         /* initial wild guess at how far apart the farthest pixel
+            pair we will be eliminating will be.  Larger
+            numbers mean more areas will be allocated, Smaller
+            numbers run the risk of not saving enough data, and
+            having to do this all over again.
+
+            I have not done extensive checking on this number.
+            */
+         max_d = 96;
+
+         while (num_new_palette > maximum_colors)
+         {
+            for (i = 0; i < num_new_palette - 1; i++)
+            {
+               int j;
+
+               for (j = i + 1; j < num_new_palette; j++)
+               {
+                  int d;
+
+                  d = PNG_COLOR_DIST(palette[i], palette[j]);
+
+                  if (d <= max_d)
+                  {
+
+                     t = (png_dsortp)png_malloc_warn(png_ptr,
+                         (png_uint_32)(png_sizeof(png_dsort)));
+                     if (t == NULL)
+                         break;
+                     t->next = hash[d];
+                     t->left = (png_byte)i;
+                     t->right = (png_byte)j;
+                     hash[d] = t;
+                  }
+               }
+               if (t == NULL)
+                  break;
+            }
+
+            if (t != NULL)
+            for (i = 0; i <= max_d; i++)
+            {
+               if (hash[i] != NULL)
+               {
+                  png_dsortp p;
+
+                  for (p = hash[i]; p; p = p->next)
+                  {
+                     if ((int)png_ptr->index_to_palette[p->left]
+                        < num_new_palette &&
+                        (int)png_ptr->index_to_palette[p->right]
+                        < num_new_palette)
+                     {
+                        int j, next_j;
+
+                        if (num_new_palette & 0x01)
+                        {
+                           j = p->left;
+                           next_j = p->right;
+                        }
+                        else
+                        {
+                           j = p->right;
+                           next_j = p->left;
+                        }
+
+                        num_new_palette--;
+                        palette[png_ptr->index_to_palette[j]]
+                          = palette[num_new_palette];
+                        if (!full_dither)
+                        {
+                           int k;
+
+                           for (k = 0; k < num_palette; k++)
+                           {
+                              if (png_ptr->dither_index[k] ==
+                                 png_ptr->index_to_palette[j])
+                                 png_ptr->dither_index[k] =
+                                    png_ptr->index_to_palette[next_j];
+                              if ((int)png_ptr->dither_index[k] ==
+                                 num_new_palette)
+                                 png_ptr->dither_index[k] =
+                                    png_ptr->index_to_palette[j];
+                           }
+                        }
+
+                        png_ptr->index_to_palette[png_ptr->palette_to_index
+                           [num_new_palette]] = png_ptr->index_to_palette[j];
+                        png_ptr->palette_to_index[png_ptr->index_to_palette[j]]
+                           = png_ptr->palette_to_index[num_new_palette];
+
+                        png_ptr->index_to_palette[j] = (png_byte)num_new_palette;
+                        png_ptr->palette_to_index[num_new_palette] = (png_byte)j;
+                     }
+                     if (num_new_palette <= maximum_colors)
+                        break;
+                  }
+                  if (num_new_palette <= maximum_colors)
+                     break;
+               }
+            }
+
+            for (i = 0; i < 769; i++)
+            {
+               if (hash[i] != NULL)
+               {
+                  png_dsortp p = hash[i];
+                  while (p)
+                  {
+                     t = p->next;
+                     png_free(png_ptr, p);
+                     p = t;
+                  }
+               }
+               hash[i] = 0;
+            }
+            max_d += 96;
+         }
+         png_free(png_ptr, hash);
+         png_free(png_ptr, png_ptr->palette_to_index);
+         png_free(png_ptr, png_ptr->index_to_palette);
+         png_ptr->palette_to_index=NULL;
+         png_ptr->index_to_palette=NULL;
+      }
+      num_palette = maximum_colors;
+   }
+   if (png_ptr->palette == NULL)
+   {
+      png_ptr->palette = palette;
+   }
+   png_ptr->num_palette = (png_uint_16)num_palette;
+
+   if (full_dither)
+   {
+      int i;
+      png_bytep distance;
+      int total_bits = PNG_DITHER_RED_BITS + PNG_DITHER_GREEN_BITS +
+         PNG_DITHER_BLUE_BITS;
+      int num_red = (1 << PNG_DITHER_RED_BITS);
+      int num_green = (1 << PNG_DITHER_GREEN_BITS);
+      int num_blue = (1 << PNG_DITHER_BLUE_BITS);
+      png_size_t num_entries = ((png_size_t)1 << total_bits);
+
+      png_ptr->palette_lookup = (png_bytep )png_malloc(png_ptr,
+         (png_uint_32)(num_entries * png_sizeof (png_byte)));
+
+      png_memset(png_ptr->palette_lookup, 0, num_entries *
+         png_sizeof (png_byte));
+
+      distance = (png_bytep)png_malloc(png_ptr, (png_uint_32)(num_entries *
+         png_sizeof(png_byte)));
+
+      png_memset(distance, 0xff, num_entries * png_sizeof(png_byte));
+
+      for (i = 0; i < num_palette; i++)
+      {
+         int ir, ig, ib;
+         int r = (palette[i].red >> (8 - PNG_DITHER_RED_BITS));
+         int g = (palette[i].green >> (8 - PNG_DITHER_GREEN_BITS));
+         int b = (palette[i].blue >> (8 - PNG_DITHER_BLUE_BITS));
+
+         for (ir = 0; ir < num_red; ir++)
+         {
+            /* int dr = abs(ir - r); */
+            int dr = ((ir > r) ? ir - r : r - ir);
+            int index_r = (ir << (PNG_DITHER_BLUE_BITS + PNG_DITHER_GREEN_BITS));
+
+            for (ig = 0; ig < num_green; ig++)
+            {
+               /* int dg = abs(ig - g); */
+               int dg = ((ig > g) ? ig - g : g - ig);
+               int dt = dr + dg;
+               int dm = ((dr > dg) ? dr : dg);
+               int index_g = index_r | (ig << PNG_DITHER_BLUE_BITS);
+
+               for (ib = 0; ib < num_blue; ib++)
+               {
+                  int d_index = index_g | ib;
+                  /* int db = abs(ib - b); */
+                  int db = ((ib > b) ? ib - b : b - ib);
+                  int dmax = ((dm > db) ? dm : db);
+                  int d = dmax + dt + db;
+
+                  if (d < (int)distance[d_index])
+                  {
+                     distance[d_index] = (png_byte)d;
+                     png_ptr->palette_lookup[d_index] = (png_byte)i;
+                  }
+               }
+            }
+         }
+      }
+
+      png_free(png_ptr, distance);
+   }
+}
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
+/* Transform the image from the file_gamma to the screen_gamma.  We
+ * only do transformations on images where the file_gamma and screen_gamma
+ * are not close reciprocals, otherwise it slows things down slightly, and
+ * also needlessly introduces small errors.
+ *
+ * We will turn off gamma transformation later if no semitransparent entries
+ * are present in the tRNS array for palette images.  We can't do it here
+ * because we don't necessarily have the tRNS chunk yet.
+ */
+void PNGAPI
+png_set_gamma(png_structp png_ptr, double scrn_gamma, double file_gamma)
+{
+   png_debug(1, "in png_set_gamma\n");
+   if ((fabs(scrn_gamma * file_gamma - 1.0) > PNG_GAMMA_THRESHOLD) ||
+       (png_ptr->color_type & PNG_COLOR_MASK_ALPHA) ||
+       (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE))
+     png_ptr->transformations |= PNG_GAMMA;
+   png_ptr->gamma = (float)file_gamma;
+   png_ptr->screen_gamma = (float)scrn_gamma;
+}
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+/* Expand paletted images to RGB, expand grayscale images of
+ * less than 8-bit depth to 8-bit depth, and expand tRNS chunks
+ * to alpha channels.
+ */
+void PNGAPI
+png_set_expand(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_expand\n");
+   png_ptr->transformations |= PNG_EXPAND;
+}
+
+/* GRR 19990627:  the following three functions currently are identical
+ *  to png_set_expand().  However, it is entirely reasonable that someone
+ *  might wish to expand an indexed image to RGB but *not* expand a single,
+ *  fully transparent palette entry to a full alpha channel--perhaps instead
+ *  convert tRNS to the grayscale/RGB format (16-bit RGB value), or replace
+ *  the transparent color with a particular RGB value, or drop tRNS entirely.
+ *  IOW, a future version of the library may make the transformations flag
+ *  a bit more fine-grained, with separate bits for each of these three
+ *  functions.
+ *
+ *  More to the point, these functions make it obvious what libpng will be
+ *  doing, whereas "expand" can (and does) mean any number of things.
+ */
+
+/* Expand paletted images to RGB. */
+void PNGAPI
+png_set_palette_to_rgb(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_expand\n");
+   png_ptr->transformations |= PNG_EXPAND;
+}
+
+/* Expand grayscale images of less than 8-bit depth to 8 bits. */
+void PNGAPI
+png_set_gray_1_2_4_to_8(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_expand\n");
+   png_ptr->transformations |= PNG_EXPAND;
+}
+
+/* Expand tRNS chunks to alpha channels. */
+void PNGAPI
+png_set_tRNS_to_alpha(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_expand\n");
+   png_ptr->transformations |= PNG_EXPAND;
+}
+#endif /* defined(PNG_READ_EXPAND_SUPPORTED) */
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+void PNGAPI
+png_set_gray_to_rgb(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_gray_to_rgb\n");
+   png_ptr->transformations |= PNG_GRAY_TO_RGB;
+}
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+#if defined(PNG_FLOATING_POINT_SUPPORTED)
+/* Convert a RGB image to a grayscale of the same width.  This allows us,
+ * for example, to convert a 24 bpp RGB image into an 8 bpp grayscale image.
+ */
+
+void PNGAPI
+png_set_rgb_to_gray(png_structp png_ptr, int error_action, double red,
+   double green)
+{
+      int red_fixed = (int)((float)red*100000.0 + 0.5);
+      int green_fixed = (int)((float)green*100000.0 + 0.5);
+      png_set_rgb_to_gray_fixed(png_ptr, error_action, red_fixed, green_fixed);
+}
+#endif
+
+void PNGAPI
+png_set_rgb_to_gray_fixed(png_structp png_ptr, int error_action,
+   png_fixed_point red, png_fixed_point green)
+{
+   png_debug(1, "in png_set_rgb_to_gray\n");
+   switch(error_action)
+   {
+      case 1: png_ptr->transformations |= PNG_RGB_TO_GRAY;
+              break;
+      case 2: png_ptr->transformations |= PNG_RGB_TO_GRAY_WARN;
+              break;
+      case 3: png_ptr->transformations |= PNG_RGB_TO_GRAY_ERR;
+   }
+   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+      png_ptr->transformations |= PNG_EXPAND;
+#else
+   {
+      png_warning(png_ptr, "Cannot do RGB_TO_GRAY without EXPAND_SUPPORTED.");
+      png_ptr->transformations &= ~PNG_RGB_TO_GRAY;
+   }
+#endif
+   {
+      png_uint_16 red_int, green_int;
+      if(red < 0 || green < 0)
+      {
+         red_int   =  6968; /* .212671 * 32768 + .5 */
+         green_int = 23434; /* .715160 * 32768 + .5 */
+      }
+      else if(red + green < 100000L)
+      {
+        red_int = (png_uint_16)(((png_uint_32)red*32768L)/100000L);
+        green_int = (png_uint_16)(((png_uint_32)green*32768L)/100000L);
+      }
+      else
+      {
+         png_warning(png_ptr, "ignoring out of range rgb_to_gray coefficients");
+         red_int   =  6968;
+         green_int = 23434;
+      }
+      png_ptr->rgb_to_gray_red_coeff   = red_int;
+      png_ptr->rgb_to_gray_green_coeff = green_int;
+      png_ptr->rgb_to_gray_blue_coeff  = (png_uint_16)(32768-red_int-green_int);
+   }
+}
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_LEGACY_SUPPORTED)
+void PNGAPI
+png_set_read_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
+   read_user_transform_fn)
+{
+   png_debug(1, "in png_set_read_user_transform_fn\n");
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+   png_ptr->transformations |= PNG_USER_TRANSFORM;
+   png_ptr->read_user_transform_fn = read_user_transform_fn;
+#endif
+#ifdef PNG_LEGACY_SUPPORTED
+   if(read_user_transform_fn)
+      png_warning(png_ptr,
+        "This version of libpng does not support user transforms");
+#endif
+}
+#endif
+
+/* Initialize everything needed for the read.  This includes modifying
+ * the palette.
+ */
+void /* PRIVATE */
+png_init_read_transformations(png_structp png_ptr)
+{
+   png_debug(1, "in png_init_read_transformations\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if(png_ptr != NULL)
+#endif
+  {
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) || defined(PNG_READ_SHIFT_SUPPORTED) \
+ || defined(PNG_READ_GAMMA_SUPPORTED)
+   int color_type = png_ptr->color_type;
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED) && defined(PNG_READ_BACKGROUND_SUPPORTED)
+   if ((png_ptr->transformations & PNG_BACKGROUND_EXPAND) &&
+       (png_ptr->transformations & PNG_EXPAND))
+   {
+      if (!(color_type & PNG_COLOR_MASK_COLOR))  /* i.e., GRAY or GRAY_ALPHA */
+      {
+         /* expand background chunk. */
+         switch (png_ptr->bit_depth)
+         {
+            case 1:
+               png_ptr->background.gray *= (png_uint_16)0xff;
+               png_ptr->background.red = png_ptr->background.green
+                 =  png_ptr->background.blue = png_ptr->background.gray;
+               break;
+            case 2:
+               png_ptr->background.gray *= (png_uint_16)0x55;
+               png_ptr->background.red = png_ptr->background.green
+                 = png_ptr->background.blue = png_ptr->background.gray;
+               break;
+            case 4:
+               png_ptr->background.gray *= (png_uint_16)0x11;
+               png_ptr->background.red = png_ptr->background.green
+                 = png_ptr->background.blue = png_ptr->background.gray;
+               break;
+            case 8:
+            case 16:
+               png_ptr->background.red = png_ptr->background.green
+                 = png_ptr->background.blue = png_ptr->background.gray;
+               break;
+         }
+      }
+      else if (color_type == PNG_COLOR_TYPE_PALETTE)
+      {
+         png_ptr->background.red   =
+            png_ptr->palette[png_ptr->background.index].red;
+         png_ptr->background.green =
+            png_ptr->palette[png_ptr->background.index].green;
+         png_ptr->background.blue  =
+            png_ptr->palette[png_ptr->background.index].blue;
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
+        if (png_ptr->transformations & PNG_INVERT_ALPHA)
+        {
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+           if (!(png_ptr->transformations & PNG_EXPAND))
+#endif
+           {
+           /* invert the alpha channel (in tRNS) unless the pixels are
+              going to be expanded, in which case leave it for later */
+              int i,istop;
+              istop=(int)png_ptr->num_trans;
+              for (i=0; i<istop; i++)
+                 png_ptr->trans[i] = (png_byte)(255 - png_ptr->trans[i]);
+           }
+        }
+#endif
+
+      }
+   }
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED)
+   png_ptr->background_1 = png_ptr->background;
+#endif
+#if defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
+
+   if ((color_type == PNG_COLOR_TYPE_PALETTE && png_ptr->num_trans != 0)
+       && (fabs(png_ptr->screen_gamma * png_ptr->gamma - 1.0)
+         < PNG_GAMMA_THRESHOLD))
+   {
+    int i,k;
+    k=0;
+    for (i=0; i<png_ptr->num_trans; i++)
+    {
+      if (png_ptr->trans[i] != 0 && png_ptr->trans[i] != 0xff)
+        k=1; /* partial transparency is present */
+    }
+    if (k == 0)
+      png_ptr->transformations &= (~PNG_GAMMA);
+   }
+
+   if (png_ptr->transformations & (PNG_GAMMA | PNG_RGB_TO_GRAY))
+   {
+      png_build_gamma_table(png_ptr);
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+      if (png_ptr->transformations & PNG_BACKGROUND)
+      {
+         if (color_type == PNG_COLOR_TYPE_PALETTE)
+         {
+           /* could skip if no transparency and 
+           */
+            png_color back, back_1;
+            png_colorp palette = png_ptr->palette;
+            int num_palette = png_ptr->num_palette;
+            int i;
+            if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_FILE)
+            {
+               back.red = png_ptr->gamma_table[png_ptr->background.red];
+               back.green = png_ptr->gamma_table[png_ptr->background.green];
+               back.blue = png_ptr->gamma_table[png_ptr->background.blue];
+
+               back_1.red = png_ptr->gamma_to_1[png_ptr->background.red];
+               back_1.green = png_ptr->gamma_to_1[png_ptr->background.green];
+               back_1.blue = png_ptr->gamma_to_1[png_ptr->background.blue];
+            }
+            else
+            {
+               double g, gs;
+
+               switch (png_ptr->background_gamma_type)
+               {
+                  case PNG_BACKGROUND_GAMMA_SCREEN:
+                     g = (png_ptr->screen_gamma);
+                     gs = 1.0;
+                     break;
+                  case PNG_BACKGROUND_GAMMA_FILE:
+                     g = 1.0 / (png_ptr->gamma);
+                     gs = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma);
+                     break;
+                  case PNG_BACKGROUND_GAMMA_UNIQUE:
+                     g = 1.0 / (png_ptr->background_gamma);
+                     gs = 1.0 / (png_ptr->background_gamma *
+                                 png_ptr->screen_gamma);
+                     break;
+                  default:
+                     g = 1.0;    /* back_1 */
+                     gs = 1.0;   /* back */
+               }
+
+               if ( fabs(gs - 1.0) < PNG_GAMMA_THRESHOLD)
+               {
+                  back.red   = (png_byte)png_ptr->background.red;
+                  back.green = (png_byte)png_ptr->background.green;
+                  back.blue  = (png_byte)png_ptr->background.blue;
+               }
+               else
+               {
+                  back.red = (png_byte)(pow(
+                     (double)png_ptr->background.red/255, gs) * 255.0 + .5);
+                  back.green = (png_byte)(pow(
+                     (double)png_ptr->background.green/255, gs) * 255.0 + .5);
+                  back.blue = (png_byte)(pow(
+                     (double)png_ptr->background.blue/255, gs) * 255.0 + .5);
+               }
+
+               back_1.red = (png_byte)(pow(
+                  (double)png_ptr->background.red/255, g) * 255.0 + .5);
+               back_1.green = (png_byte)(pow(
+                  (double)png_ptr->background.green/255, g) * 255.0 + .5);
+               back_1.blue = (png_byte)(pow(
+                  (double)png_ptr->background.blue/255, g) * 255.0 + .5);
+            }
+            for (i = 0; i < num_palette; i++)
+            {
+               if (i < (int)png_ptr->num_trans && png_ptr->trans[i] != 0xff)
+               {
+                  if (png_ptr->trans[i] == 0)
+                  {
+                     palette[i] = back;
+                  }
+                  else /* if (png_ptr->trans[i] != 0xff) */
+                  {
+                     png_byte v, w;
+
+                     v = png_ptr->gamma_to_1[palette[i].red];
+                     png_composite(w, v, png_ptr->trans[i], back_1.red);
+                     palette[i].red = png_ptr->gamma_from_1[w];
+
+                     v = png_ptr->gamma_to_1[palette[i].green];
+                     png_composite(w, v, png_ptr->trans[i], back_1.green);
+                     palette[i].green = png_ptr->gamma_from_1[w];
+
+                     v = png_ptr->gamma_to_1[palette[i].blue];
+                     png_composite(w, v, png_ptr->trans[i], back_1.blue);
+                     palette[i].blue = png_ptr->gamma_from_1[w];
+                  }
+               }
+               else
+               {
+                  palette[i].red = png_ptr->gamma_table[palette[i].red];
+                  palette[i].green = png_ptr->gamma_table[palette[i].green];
+                  palette[i].blue = png_ptr->gamma_table[palette[i].blue];
+               }
+            }
+         }
+         /* if (png_ptr->background_gamma_type!=PNG_BACKGROUND_GAMMA_UNKNOWN) */
+         else
+         /* color_type != PNG_COLOR_TYPE_PALETTE */
+         {
+            double m = (double)(((png_uint_32)1 << png_ptr->bit_depth) - 1);
+            double g = 1.0;
+            double gs = 1.0;
+
+            switch (png_ptr->background_gamma_type)
+            {
+               case PNG_BACKGROUND_GAMMA_SCREEN:
+                  g = (png_ptr->screen_gamma);
+                  gs = 1.0;
+                  break;
+               case PNG_BACKGROUND_GAMMA_FILE:
+                  g = 1.0 / (png_ptr->gamma);
+                  gs = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma);
+                  break;
+               case PNG_BACKGROUND_GAMMA_UNIQUE:
+                  g = 1.0 / (png_ptr->background_gamma);
+                  gs = 1.0 / (png_ptr->background_gamma *
+                     png_ptr->screen_gamma);
+                  break;
+            }
+
+            png_ptr->background_1.gray = (png_uint_16)(pow(
+               (double)png_ptr->background.gray / m, g) * m + .5);
+            png_ptr->background.gray = (png_uint_16)(pow(
+               (double)png_ptr->background.gray / m, gs) * m + .5);
+
+            if ((png_ptr->background.red != png_ptr->background.green) ||
+                (png_ptr->background.red != png_ptr->background.blue) ||
+                (png_ptr->background.red != png_ptr->background.gray))
+            {
+               /* RGB or RGBA with color background */
+               png_ptr->background_1.red = (png_uint_16)(pow(
+                  (double)png_ptr->background.red / m, g) * m + .5);
+               png_ptr->background_1.green = (png_uint_16)(pow(
+                  (double)png_ptr->background.green / m, g) * m + .5);
+               png_ptr->background_1.blue = (png_uint_16)(pow(
+                  (double)png_ptr->background.blue / m, g) * m + .5);
+               png_ptr->background.red = (png_uint_16)(pow(
+                  (double)png_ptr->background.red / m, gs) * m + .5);
+               png_ptr->background.green = (png_uint_16)(pow(
+                  (double)png_ptr->background.green / m, gs) * m + .5);
+               png_ptr->background.blue = (png_uint_16)(pow(
+                  (double)png_ptr->background.blue / m, gs) * m + .5);
+            }
+            else
+            {
+               /* GRAY, GRAY ALPHA, RGB, or RGBA with gray background */
+               png_ptr->background_1.red = png_ptr->background_1.green
+                 = png_ptr->background_1.blue = png_ptr->background_1.gray;
+               png_ptr->background.red = png_ptr->background.green
+                 = png_ptr->background.blue = png_ptr->background.gray;
+            }
+         }
+      }
+      else
+      /* transformation does not include PNG_BACKGROUND */
+#endif /* PNG_READ_BACKGROUND_SUPPORTED */
+      if (color_type == PNG_COLOR_TYPE_PALETTE)
+      {
+         png_colorp palette = png_ptr->palette;
+         int num_palette = png_ptr->num_palette;
+         int i;
+
+         for (i = 0; i < num_palette; i++)
+         {
+            palette[i].red = png_ptr->gamma_table[palette[i].red];
+            palette[i].green = png_ptr->gamma_table[palette[i].green];
+            palette[i].blue = png_ptr->gamma_table[palette[i].blue];
+         }
+      }
+   }
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+   else
+#endif
+#endif /* PNG_READ_GAMMA_SUPPORTED && PNG_FLOATING_POINT_SUPPORTED */
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+   /* No GAMMA transformation */
+   if ((png_ptr->transformations & PNG_BACKGROUND) &&
+       (color_type == PNG_COLOR_TYPE_PALETTE))
+   {
+      int i;
+      int istop = (int)png_ptr->num_trans;
+      png_color back;
+      png_colorp palette = png_ptr->palette;
+
+      back.red   = (png_byte)png_ptr->background.red;
+      back.green = (png_byte)png_ptr->background.green;
+      back.blue  = (png_byte)png_ptr->background.blue;
+
+      for (i = 0; i < istop; i++)
+      {
+         if (png_ptr->trans[i] == 0)
+         {
+            palette[i] = back;
+         }
+         else if (png_ptr->trans[i] != 0xff)
+         {
+            /* The png_composite() macro is defined in png.h */
+            png_composite(palette[i].red, palette[i].red,
+               png_ptr->trans[i], back.red);
+            png_composite(palette[i].green, palette[i].green,
+               png_ptr->trans[i], back.green);
+            png_composite(palette[i].blue, palette[i].blue,
+               png_ptr->trans[i], back.blue);
+         }
+      }
+   }
+#endif /* PNG_READ_BACKGROUND_SUPPORTED */
+
+#if defined(PNG_READ_SHIFT_SUPPORTED)
+   if ((png_ptr->transformations & PNG_SHIFT) &&
+      (color_type == PNG_COLOR_TYPE_PALETTE))
+   {
+      png_uint_16 i;
+      png_uint_16 istop = png_ptr->num_palette;
+      int sr = 8 - png_ptr->sig_bit.red;
+      int sg = 8 - png_ptr->sig_bit.green;
+      int sb = 8 - png_ptr->sig_bit.blue;
+
+      if (sr < 0 || sr > 8)
+         sr = 0;
+      if (sg < 0 || sg > 8)
+         sg = 0;
+      if (sb < 0 || sb > 8)
+         sb = 0;
+      for (i = 0; i < istop; i++)
+      {
+         png_ptr->palette[i].red >>= sr;
+         png_ptr->palette[i].green >>= sg;
+         png_ptr->palette[i].blue >>= sb;
+      }
+   }
+#endif  /* PNG_READ_SHIFT_SUPPORTED */
+ }
+#if !defined(PNG_READ_GAMMA_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED) \
+ && !defined(PNG_READ_BACKGROUND_SUPPORTED)
+   if(png_ptr)
+      return;
+#endif
+}
+
+/* Modify the info structure to reflect the transformations.  The
+ * info should be updated so a PNG file could be written with it,
+ * assuming the transformations result in valid PNG data.
+ */
+void /* PRIVATE */
+png_read_transform_info(png_structp png_ptr, png_infop info_ptr)
+{
+   png_debug(1, "in png_read_transform_info\n");
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+   if (png_ptr->transformations & PNG_EXPAND)
+   {
+      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      {
+         if (png_ptr->num_trans)
+            info_ptr->color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+         else
+            info_ptr->color_type = PNG_COLOR_TYPE_RGB;
+         info_ptr->bit_depth = 8;
+         info_ptr->num_trans = 0;
+      }
+      else
+      {
+         if (png_ptr->num_trans)
+            info_ptr->color_type |= PNG_COLOR_MASK_ALPHA;
+         if (info_ptr->bit_depth < 8)
+            info_ptr->bit_depth = 8;
+         info_ptr->num_trans = 0;
+      }
+   }
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+   if (png_ptr->transformations & PNG_BACKGROUND)
+   {
+      info_ptr->color_type &= ~PNG_COLOR_MASK_ALPHA;
+      info_ptr->num_trans = 0;
+      info_ptr->background = png_ptr->background;
+   }
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+   if (png_ptr->transformations & PNG_GAMMA)
+   {
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+      info_ptr->gamma = png_ptr->gamma;
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+      info_ptr->int_gamma = png_ptr->int_gamma;
+#endif
+   }
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+   if ((png_ptr->transformations & PNG_16_TO_8) && (info_ptr->bit_depth == 16))
+      info_ptr->bit_depth = 8;
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+   if (png_ptr->transformations & PNG_DITHER)
+   {
+      if (((info_ptr->color_type == PNG_COLOR_TYPE_RGB) ||
+         (info_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)) &&
+         png_ptr->palette_lookup && info_ptr->bit_depth == 8)
+      {
+         info_ptr->color_type = PNG_COLOR_TYPE_PALETTE;
+      }
+   }
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED)
+   if ((png_ptr->transformations & PNG_PACK) && (info_ptr->bit_depth < 8))
+      info_ptr->bit_depth = 8;
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+   if (png_ptr->transformations & PNG_GRAY_TO_RGB)
+      info_ptr->color_type |= PNG_COLOR_MASK_COLOR;
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+   if (png_ptr->transformations & PNG_RGB_TO_GRAY)
+      info_ptr->color_type &= ~PNG_COLOR_MASK_COLOR;
+#endif
+
+   if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      info_ptr->channels = 1;
+   else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
+      info_ptr->channels = 3;
+   else
+      info_ptr->channels = 1;
+
+#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+   if (png_ptr->flags & PNG_FLAG_STRIP_ALPHA)
+      info_ptr->color_type &= ~PNG_COLOR_MASK_ALPHA;
+#endif
+
+   if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
+      info_ptr->channels++;
+
+#if defined(PNG_READ_FILLER_SUPPORTED)
+   /* STRIP_ALPHA and FILLER allowed:  MASK_ALPHA bit stripped above */
+   if ((png_ptr->transformations & PNG_FILLER) &&
+       ((info_ptr->color_type == PNG_COLOR_TYPE_RGB) ||
+       (info_ptr->color_type == PNG_COLOR_TYPE_GRAY)))
+   {
+      info_ptr->channels++;
+      /* if adding a true alpha channel not just filler */
+#if !defined(PNG_1_0_X)
+      if (png_ptr->transformations & PNG_ADD_ALPHA)
+        info_ptr->color_type |= PNG_COLOR_MASK_ALPHA;
+#endif
+   }
+#endif
+
+#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) && \
+defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+   if(png_ptr->transformations & PNG_USER_TRANSFORM)
+     {
+       if(info_ptr->bit_depth < png_ptr->user_transform_depth)
+         info_ptr->bit_depth = png_ptr->user_transform_depth;
+       if(info_ptr->channels < png_ptr->user_transform_channels)
+         info_ptr->channels = png_ptr->user_transform_channels;
+     }
+#endif
+
+   info_ptr->pixel_depth = (png_byte)(info_ptr->channels *
+      info_ptr->bit_depth);
+
+   info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth,info_ptr->width);
+
+#if !defined(PNG_READ_EXPAND_SUPPORTED)
+   if(png_ptr)
+      return;
+#endif
+}
+
+/* Transform the row.  The order of transformations is significant,
+ * and is very touchy.  If you add a transformation, take care to
+ * decide how it fits in with the other transformations here.
+ */
+void /* PRIVATE */
+png_do_read_transformations(png_structp png_ptr)
+{
+   png_debug(1, "in png_do_read_transformations\n");
+#if !defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (png_ptr->row_buf == NULL)
+   {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+      char msg[50];
+
+      sprintf(msg, "NULL row buffer for row %ld, pass %d", png_ptr->row_number,
+         png_ptr->pass);
+      png_error(png_ptr, msg);
+#else
+      png_error(png_ptr, "NULL row buffer");
+#endif
+   }
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+   if (png_ptr->transformations & PNG_EXPAND)
+   {
+      if (png_ptr->row_info.color_type == PNG_COLOR_TYPE_PALETTE)
+      {
+         png_do_expand_palette(&(png_ptr->row_info), png_ptr->row_buf + 1,
+            png_ptr->palette, png_ptr->trans, png_ptr->num_trans);
+      }
+      else
+      {
+         if (png_ptr->num_trans)
+            png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1,
+               &(png_ptr->trans_values));
+         else
+            png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1,
+               NULL);
+      }
+   }
+#endif
+
+#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+   if (png_ptr->flags & PNG_FLAG_STRIP_ALPHA)
+      png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
+         PNG_FLAG_FILLER_AFTER | (png_ptr->flags & PNG_FLAG_STRIP_ALPHA));
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+   if (png_ptr->transformations & PNG_RGB_TO_GRAY)
+   {
+      int rgb_error =
+         png_do_rgb_to_gray(png_ptr, &(png_ptr->row_info), png_ptr->row_buf + 1);
+      if(rgb_error)
+      {
+         png_ptr->rgb_to_gray_status=1;
+         if(png_ptr->transformations == PNG_RGB_TO_GRAY_WARN)
+            png_warning(png_ptr, "png_do_rgb_to_gray found nongray pixel");
+         if(png_ptr->transformations == PNG_RGB_TO_GRAY_ERR)
+            png_error(png_ptr, "png_do_rgb_to_gray found nongray pixel");
+      }
+   }
+#endif
+
+/*
+From Andreas Dilger e-mail to png-implement, 26 March 1998:
+
+  In most cases, the "simple transparency" should be done prior to doing
+  gray-to-RGB, or you will have to test 3x as many bytes to check if a
+  pixel is transparent.  You would also need to make sure that the
+  transparency information is upgraded to RGB.
+
+  To summarize, the current flow is:
+  - Gray + simple transparency -> compare 1 or 2 gray bytes and composite
+                                  with background "in place" if transparent,
+                                  convert to RGB if necessary
+  - Gray + alpha -> composite with gray background and remove alpha bytes,
+                                  convert to RGB if necessary
+
+  To support RGB backgrounds for gray images we need:
+  - Gray + simple transparency -> convert to RGB + simple transparency, compare
+                                  3 or 6 bytes and composite with background
+                                  "in place" if transparent (3x compare/pixel
+                                  compared to doing composite with gray bkgrnd)
+  - Gray + alpha -> convert to RGB + alpha, composite with background and
+                                  remove alpha bytes (3x float operations/pixel
+                                  compared with composite on gray background)
+
+  Greg's change will do this.  The reason it wasn't done before is for
+  performance, as this increases the per-pixel operations.  If we would check
+  in advance if the background was gray or RGB, and position the gray-to-RGB
+  transform appropriately, then it would save a lot of work/time.
+ */
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+   /* if gray -> RGB, do so now only if background is non-gray; else do later
+    * for performance reasons */
+   if ((png_ptr->transformations & PNG_GRAY_TO_RGB) &&
+       !(png_ptr->mode & PNG_BACKGROUND_IS_GRAY))
+      png_do_gray_to_rgb(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+   if ((png_ptr->transformations & PNG_BACKGROUND) &&
+      ((png_ptr->num_trans != 0 ) ||
+      (png_ptr->color_type & PNG_COLOR_MASK_ALPHA)))
+      png_do_background(&(png_ptr->row_info), png_ptr->row_buf + 1,
+         &(png_ptr->trans_values), &(png_ptr->background)
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+         , &(png_ptr->background_1),
+         png_ptr->gamma_table, png_ptr->gamma_from_1,
+         png_ptr->gamma_to_1, png_ptr->gamma_16_table,
+         png_ptr->gamma_16_from_1, png_ptr->gamma_16_to_1,
+         png_ptr->gamma_shift
+#endif
+);
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+   if ((png_ptr->transformations & PNG_GAMMA) &&
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+      !((png_ptr->transformations & PNG_BACKGROUND) &&
+      ((png_ptr->num_trans != 0) ||
+      (png_ptr->color_type & PNG_COLOR_MASK_ALPHA))) &&
+#endif
+      (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE))
+      png_do_gamma(&(png_ptr->row_info), png_ptr->row_buf + 1,
+         png_ptr->gamma_table, png_ptr->gamma_16_table,
+         png_ptr->gamma_shift);
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+   if (png_ptr->transformations & PNG_16_TO_8)
+      png_do_chop(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+   if (png_ptr->transformations & PNG_DITHER)
+   {
+      png_do_dither((png_row_infop)&(png_ptr->row_info), png_ptr->row_buf + 1,
+         png_ptr->palette_lookup, png_ptr->dither_index);
+      if(png_ptr->row_info.rowbytes == (png_uint_32)0)
+         png_error(png_ptr, "png_do_dither returned rowbytes=0");
+   }
+#endif
+
+#if defined(PNG_READ_INVERT_SUPPORTED)
+   if (png_ptr->transformations & PNG_INVERT_MONO)
+      png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED)
+   if (png_ptr->transformations & PNG_SHIFT)
+      png_do_unshift(&(png_ptr->row_info), png_ptr->row_buf + 1,
+         &(png_ptr->shift));
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED)
+   if (png_ptr->transformations & PNG_PACK)
+      png_do_unpack(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED)
+   if (png_ptr->transformations & PNG_BGR)
+      png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+   if (png_ptr->transformations & PNG_PACKSWAP)
+      png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+   /* if gray -> RGB, do so now only if we did not do so above */
+   if ((png_ptr->transformations & PNG_GRAY_TO_RGB) &&
+       (png_ptr->mode & PNG_BACKGROUND_IS_GRAY))
+      png_do_gray_to_rgb(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED)
+   if (png_ptr->transformations & PNG_FILLER)
+      png_do_read_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
+         (png_uint_32)png_ptr->filler, png_ptr->flags);
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
+   if (png_ptr->transformations & PNG_INVERT_ALPHA)
+      png_do_read_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
+   if (png_ptr->transformations & PNG_SWAP_ALPHA)
+      png_do_read_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_SWAP_SUPPORTED)
+   if (png_ptr->transformations & PNG_SWAP_BYTES)
+      png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+   if (png_ptr->transformations & PNG_USER_TRANSFORM)
+    {
+      if(png_ptr->read_user_transform_fn != NULL)
+        (*(png_ptr->read_user_transform_fn)) /* user read transform function */
+          (png_ptr,                    /* png_ptr */
+           &(png_ptr->row_info),       /* row_info:     */
+             /*  png_uint_32 width;          width of row */
+             /*  png_uint_32 rowbytes;       number of bytes in row */
+             /*  png_byte color_type;        color type of pixels */
+             /*  png_byte bit_depth;         bit depth of samples */
+             /*  png_byte channels;          number of channels (1-4) */
+             /*  png_byte pixel_depth;       bits per pixel (depth*channels) */
+           png_ptr->row_buf + 1);      /* start of pixel data for row */
+#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+      if(png_ptr->user_transform_depth)
+         png_ptr->row_info.bit_depth = png_ptr->user_transform_depth;
+      if(png_ptr->user_transform_channels)
+         png_ptr->row_info.channels = png_ptr->user_transform_channels;
+#endif
+      png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth *
+         png_ptr->row_info.channels);
+      png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
+         png_ptr->row_info.width);
+   }
+#endif
+
+}
+
+#if defined(PNG_READ_PACK_SUPPORTED)
+/* Unpack pixels of 1, 2, or 4 bits per pixel into 1 byte per pixel,
+ * without changing the actual values.  Thus, if you had a row with
+ * a bit depth of 1, you would end up with bytes that only contained
+ * the numbers 0 or 1.  If you would rather they contain 0 and 255, use
+ * png_do_shift() after this.
+ */
+void /* PRIVATE */
+png_do_unpack(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_unpack\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL && row_info->bit_depth < 8)
+#else
+   if (row_info->bit_depth < 8)
+#endif
+   {
+      png_uint_32 i;
+      png_uint_32 row_width=row_info->width;
+
+      switch (row_info->bit_depth)
+      {
+         case 1:
+         {
+            png_bytep sp = row + (png_size_t)((row_width - 1) >> 3);
+            png_bytep dp = row + (png_size_t)row_width - 1;
+            png_uint_32 shift = 7 - (int)((row_width + 7) & 0x07);
+            for (i = 0; i < row_width; i++)
+            {
+               *dp = (png_byte)((*sp >> shift) & 0x01);
+               if (shift == 7)
+               {
+                  shift = 0;
+                  sp--;
+               }
+               else
+                  shift++;
+
+               dp--;
+            }
+            break;
+         }
+         case 2:
+         {
+
+            png_bytep sp = row + (png_size_t)((row_width - 1) >> 2);
+            png_bytep dp = row + (png_size_t)row_width - 1;
+            png_uint_32 shift = (int)((3 - ((row_width + 3) & 0x03)) << 1);
+            for (i = 0; i < row_width; i++)
+            {
+               *dp = (png_byte)((*sp >> shift) & 0x03);
+               if (shift == 6)
+               {
+                  shift = 0;
+                  sp--;
+               }
+               else
+                  shift += 2;
+
+               dp--;
+            }
+            break;
+         }
+         case 4:
+         {
+            png_bytep sp = row + (png_size_t)((row_width - 1) >> 1);
+            png_bytep dp = row + (png_size_t)row_width - 1;
+            png_uint_32 shift = (int)((1 - ((row_width + 1) & 0x01)) << 2);
+            for (i = 0; i < row_width; i++)
+            {
+               *dp = (png_byte)((*sp >> shift) & 0x0f);
+               if (shift == 4)
+               {
+                  shift = 0;
+                  sp--;
+               }
+               else
+                  shift = 4;
+
+               dp--;
+            }
+            break;
+         }
+      }
+      row_info->bit_depth = 8;
+      row_info->pixel_depth = (png_byte)(8 * row_info->channels);
+      row_info->rowbytes = row_width * row_info->channels;
+   }
+}
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED)
+/* Reverse the effects of png_do_shift.  This routine merely shifts the
+ * pixels back to their significant bits values.  Thus, if you have
+ * a row of bit depth 8, but only 5 are significant, this will shift
+ * the values back to 0 through 31.
+ */
+void /* PRIVATE */
+png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits)
+{
+   png_debug(1, "in png_do_unshift\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL && sig_bits != NULL &&
+#endif
+       row_info->color_type != PNG_COLOR_TYPE_PALETTE)
+   {
+      int shift[4];
+      int channels = 0;
+      int c;
+      png_uint_16 value = 0;
+      png_uint_32 row_width = row_info->width;
+
+      if (row_info->color_type & PNG_COLOR_MASK_COLOR)
+      {
+         shift[channels++] = row_info->bit_depth - sig_bits->red;
+         shift[channels++] = row_info->bit_depth - sig_bits->green;
+         shift[channels++] = row_info->bit_depth - sig_bits->blue;
+      }
+      else
+      {
+         shift[channels++] = row_info->bit_depth - sig_bits->gray;
+      }
+      if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
+      {
+         shift[channels++] = row_info->bit_depth - sig_bits->alpha;
+      }
+
+      for (c = 0; c < channels; c++)
+      {
+         if (shift[c] <= 0)
+            shift[c] = 0;
+         else
+            value = 1;
+      }
+
+      if (!value)
+         return;
+
+      switch (row_info->bit_depth)
+      {
+         case 2:
+         {
+            png_bytep bp;
+            png_uint_32 i;
+            png_uint_32 istop = row_info->rowbytes;
+
+            for (bp = row, i = 0; i < istop; i++)
+            {
+               *bp >>= 1;
+               *bp++ &= 0x55;
+            }
+            break;
+         }
+         case 4:
+         {
+            png_bytep bp = row;
+            png_uint_32 i;
+            png_uint_32 istop = row_info->rowbytes;
+            png_byte mask = (png_byte)((((int)0xf0 >> shift[0]) & (int)0xf0) |
+               (png_byte)((int)0xf >> shift[0]));
+
+            for (i = 0; i < istop; i++)
+            {
+               *bp >>= shift[0];
+               *bp++ &= mask;
+            }
+            break;
+         }
+         case 8:
+         {
+            png_bytep bp = row;
+            png_uint_32 i;
+            png_uint_32 istop = row_width * channels;
+
+            for (i = 0; i < istop; i++)
+            {
+               *bp++ >>= shift[i%channels];
+            }
+            break;
+         }
+         case 16:
+         {
+            png_bytep bp = row;
+            png_uint_32 i;
+            png_uint_32 istop = channels * row_width;
+
+            for (i = 0; i < istop; i++)
+            {
+               value = (png_uint_16)((*bp << 8) + *(bp + 1));
+               value >>= shift[i%channels];
+               *bp++ = (png_byte)(value >> 8);
+               *bp++ = (png_byte)(value & 0xff);
+            }
+            break;
+         }
+      }
+   }
+}
+#endif
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+/* chop rows of bit depth 16 down to 8 */
+void /* PRIVATE */
+png_do_chop(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_chop\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL && row_info->bit_depth == 16)
+#else
+   if (row_info->bit_depth == 16)
+#endif
+   {
+      png_bytep sp = row;
+      png_bytep dp = row;
+      png_uint_32 i;
+      png_uint_32 istop = row_info->width * row_info->channels;
+
+      for (i = 0; i<istop; i++, sp += 2, dp++)
+      {
+#if defined(PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED)
+      /* This does a more accurate scaling of the 16-bit color
+       * value, rather than a simple low-byte truncation.
+       *
+       * What the ideal calculation should be:
+       *   *dp = (((((png_uint_32)(*sp) << 8) |
+       *          (png_uint_32)(*(sp + 1))) * 255 + 127) / (png_uint_32)65535L;
+       *
+       * GRR: no, I think this is what it really should be:
+       *   *dp = (((((png_uint_32)(*sp) << 8) |
+       *           (png_uint_32)(*(sp + 1))) + 128L) / (png_uint_32)257L;
+       *
+       * GRR: here's the exact calculation with shifts:
+       *   temp = (((png_uint_32)(*sp) << 8) | (png_uint_32)(*(sp + 1))) + 128L;
+       *   *dp = (temp - (temp >> 8)) >> 8;
+       *
+       * Approximate calculation with shift/add instead of multiply/divide:
+       *   *dp = ((((png_uint_32)(*sp) << 8) |
+       *          (png_uint_32)((int)(*(sp + 1)) - *sp)) + 128) >> 8;
+       *
+       * What we actually do to avoid extra shifting and conversion:
+       */
+
+         *dp = *sp + ((((int)(*(sp + 1)) - *sp) > 128) ? 1 : 0);
+#else
+       /* Simply discard the low order byte */
+         *dp = *sp;
+#endif
+      }
+      row_info->bit_depth = 8;
+      row_info->pixel_depth = (png_byte)(8 * row_info->channels);
+      row_info->rowbytes = row_info->width * row_info->channels;
+   }
+}
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
+void /* PRIVATE */
+png_do_read_swap_alpha(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_read_swap_alpha\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL)
+#endif
+   {
+      png_uint_32 row_width = row_info->width;
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+      {
+         /* This converts from RGBA to ARGB */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp = row + row_info->rowbytes;
+            png_bytep dp = sp;
+            png_byte save;
+            png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               save = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = save;
+            }
+         }
+         /* This converts from RRGGBBAA to AARRGGBB */
+         else
+         {
+            png_bytep sp = row + row_info->rowbytes;
+            png_bytep dp = sp;
+            png_byte save[2];
+            png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               save[0] = *(--sp);
+               save[1] = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = save[0];
+               *(--dp) = save[1];
+            }
+         }
+      }
+      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      {
+         /* This converts from GA to AG */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp = row + row_info->rowbytes;
+            png_bytep dp = sp;
+            png_byte save;
+            png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               save = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = save;
+            }
+         }
+         /* This converts from GGAA to AAGG */
+         else
+         {
+            png_bytep sp = row + row_info->rowbytes;
+            png_bytep dp = sp;
+            png_byte save[2];
+            png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               save[0] = *(--sp);
+               save[1] = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = save[0];
+               *(--dp) = save[1];
+            }
+         }
+      }
+   }
+}
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
+void /* PRIVATE */
+png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_read_invert_alpha\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL)
+#endif
+   {
+      png_uint_32 row_width = row_info->width;
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+      {
+         /* This inverts the alpha channel in RGBA */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp = row + row_info->rowbytes;
+            png_bytep dp = sp;
+            png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               *(--dp) = (png_byte)(255 - *(--sp));
+
+/*             This does nothing:
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               We can replace it with:
+*/
+               sp-=3;
+               dp=sp;
+            }
+         }
+         /* This inverts the alpha channel in RRGGBBAA */
+         else
+         {
+            png_bytep sp = row + row_info->rowbytes;
+            png_bytep dp = sp;
+            png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               *(--dp) = (png_byte)(255 - *(--sp));
+               *(--dp) = (png_byte)(255 - *(--sp));
+
+/*             This does nothing:
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               We can replace it with:
+*/
+               sp-=6;
+               dp=sp;
+            }
+         }
+      }
+      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      {
+         /* This inverts the alpha channel in GA */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp = row + row_info->rowbytes;
+            png_bytep dp = sp;
+            png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               *(--dp) = (png_byte)(255 - *(--sp));
+               *(--dp) = *(--sp);
+            }
+         }
+         /* This inverts the alpha channel in GGAA */
+         else
+         {
+            png_bytep sp  = row + row_info->rowbytes;
+            png_bytep dp = sp;
+            png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               *(--dp) = (png_byte)(255 - *(--sp));
+               *(--dp) = (png_byte)(255 - *(--sp));
+/*
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+*/
+               sp-=2;
+               dp=sp;
+            }
+         }
+      }
+   }
+}
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED)
+/* Add filler channel if we have RGB color */
+void /* PRIVATE */
+png_do_read_filler(png_row_infop row_info, png_bytep row,
+   png_uint_32 filler, png_uint_32 flags)
+{
+   png_uint_32 i;
+   png_uint_32 row_width = row_info->width;
+
+   png_byte hi_filler = (png_byte)((filler>>8) & 0xff);
+   png_byte lo_filler = (png_byte)(filler & 0xff);
+
+   png_debug(1, "in png_do_read_filler\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL  && row_info != NULL &&
+#endif
+       row_info->color_type == PNG_COLOR_TYPE_GRAY)
+   {
+      if(row_info->bit_depth == 8)
+      {
+         /* This changes the data from G to GX */
+         if (flags & PNG_FLAG_FILLER_AFTER)
+         {
+            png_bytep sp = row + (png_size_t)row_width;
+            png_bytep dp =  sp + (png_size_t)row_width;
+            for (i = 1; i < row_width; i++)
+            {
+               *(--dp) = lo_filler;
+               *(--dp) = *(--sp);
+            }
+            *(--dp) = lo_filler;
+            row_info->channels = 2;
+            row_info->pixel_depth = 16;
+            row_info->rowbytes = row_width * 2;
+         }
+      /* This changes the data from G to XG */
+         else
+         {
+            png_bytep sp = row + (png_size_t)row_width;
+            png_bytep dp = sp  + (png_size_t)row_width;
+            for (i = 0; i < row_width; i++)
+            {
+               *(--dp) = *(--sp);
+               *(--dp) = lo_filler;
+            }
+            row_info->channels = 2;
+            row_info->pixel_depth = 16;
+            row_info->rowbytes = row_width * 2;
+         }
+      }
+      else if(row_info->bit_depth == 16)
+      {
+         /* This changes the data from GG to GGXX */
+         if (flags & PNG_FLAG_FILLER_AFTER)
+         {
+            png_bytep sp = row + (png_size_t)row_width * 2;
+            png_bytep dp = sp  + (png_size_t)row_width * 2;
+            for (i = 1; i < row_width; i++)
+            {
+               *(--dp) = hi_filler;
+               *(--dp) = lo_filler;
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+            }
+            *(--dp) = hi_filler;
+            *(--dp) = lo_filler;
+            row_info->channels = 2;
+            row_info->pixel_depth = 32;
+            row_info->rowbytes = row_width * 4;
+         }
+         /* This changes the data from GG to XXGG */
+         else
+         {
+            png_bytep sp = row + (png_size_t)row_width * 2;
+            png_bytep dp = sp  + (png_size_t)row_width * 2;
+            for (i = 0; i < row_width; i++)
+            {
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = hi_filler;
+               *(--dp) = lo_filler;
+            }
+            row_info->channels = 2;
+            row_info->pixel_depth = 32;
+            row_info->rowbytes = row_width * 4;
+         }
+      }
+   } /* COLOR_TYPE == GRAY */
+   else if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+   {
+      if(row_info->bit_depth == 8)
+      {
+         /* This changes the data from RGB to RGBX */
+         if (flags & PNG_FLAG_FILLER_AFTER)
+         {
+            png_bytep sp = row + (png_size_t)row_width * 3;
+            png_bytep dp = sp  + (png_size_t)row_width;
+            for (i = 1; i < row_width; i++)
+            {
+               *(--dp) = lo_filler;
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+            }
+            *(--dp) = lo_filler;
+            row_info->channels = 4;
+            row_info->pixel_depth = 32;
+            row_info->rowbytes = row_width * 4;
+         }
+      /* This changes the data from RGB to XRGB */
+         else
+         {
+            png_bytep sp = row + (png_size_t)row_width * 3;
+            png_bytep dp = sp + (png_size_t)row_width;
+            for (i = 0; i < row_width; i++)
+            {
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = lo_filler;
+            }
+            row_info->channels = 4;
+            row_info->pixel_depth = 32;
+            row_info->rowbytes = row_width * 4;
+         }
+      }
+      else if(row_info->bit_depth == 16)
+      {
+         /* This changes the data from RRGGBB to RRGGBBXX */
+         if (flags & PNG_FLAG_FILLER_AFTER)
+         {
+            png_bytep sp = row + (png_size_t)row_width * 6;
+            png_bytep dp = sp  + (png_size_t)row_width * 2;
+            for (i = 1; i < row_width; i++)
+            {
+               *(--dp) = hi_filler;
+               *(--dp) = lo_filler;
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+            }
+            *(--dp) = hi_filler;
+            *(--dp) = lo_filler;
+            row_info->channels = 4;
+            row_info->pixel_depth = 64;
+            row_info->rowbytes = row_width * 8;
+         }
+         /* This changes the data from RRGGBB to XXRRGGBB */
+         else
+         {
+            png_bytep sp = row + (png_size_t)row_width * 6;
+            png_bytep dp = sp  + (png_size_t)row_width * 2;
+            for (i = 0; i < row_width; i++)
+            {
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = hi_filler;
+               *(--dp) = lo_filler;
+            }
+            row_info->channels = 4;
+            row_info->pixel_depth = 64;
+            row_info->rowbytes = row_width * 8;
+         }
+      }
+   } /* COLOR_TYPE == RGB */
+}
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+/* expand grayscale files to RGB, with or without alpha */
+void /* PRIVATE */
+png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
+{
+   png_uint_32 i;
+   png_uint_32 row_width = row_info->width;
+
+   png_debug(1, "in png_do_gray_to_rgb\n");
+   if (row_info->bit_depth >= 8 &&
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+      !(row_info->color_type & PNG_COLOR_MASK_COLOR))
+   {
+      if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
+      {
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp = row + (png_size_t)row_width - 1;
+            png_bytep dp = sp  + (png_size_t)row_width * 2;
+            for (i = 0; i < row_width; i++)
+            {
+               *(dp--) = *sp;
+               *(dp--) = *sp;
+               *(dp--) = *(sp--);
+            }
+         }
+         else
+         {
+            png_bytep sp = row + (png_size_t)row_width * 2 - 1;
+            png_bytep dp = sp  + (png_size_t)row_width * 4;
+            for (i = 0; i < row_width; i++)
+            {
+               *(dp--) = *sp;
+               *(dp--) = *(sp - 1);
+               *(dp--) = *sp;
+               *(dp--) = *(sp - 1);
+               *(dp--) = *(sp--);
+               *(dp--) = *(sp--);
+            }
+         }
+      }
+      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      {
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp = row + (png_size_t)row_width * 2 - 1;
+            png_bytep dp = sp  + (png_size_t)row_width * 2;
+            for (i = 0; i < row_width; i++)
+            {
+               *(dp--) = *(sp--);
+               *(dp--) = *sp;
+               *(dp--) = *sp;
+               *(dp--) = *(sp--);
+            }
+         }
+         else
+         {
+            png_bytep sp = row + (png_size_t)row_width * 4 - 1;
+            png_bytep dp = sp  + (png_size_t)row_width * 4;
+            for (i = 0; i < row_width; i++)
+            {
+               *(dp--) = *(sp--);
+               *(dp--) = *(sp--);
+               *(dp--) = *sp;
+               *(dp--) = *(sp - 1);
+               *(dp--) = *sp;
+               *(dp--) = *(sp - 1);
+               *(dp--) = *(sp--);
+               *(dp--) = *(sp--);
+            }
+         }
+      }
+      row_info->channels += (png_byte)2;
+      row_info->color_type |= PNG_COLOR_MASK_COLOR;
+      row_info->pixel_depth = (png_byte)(row_info->channels *
+         row_info->bit_depth);
+      row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+   }
+}
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+/* reduce RGB files to grayscale, with or without alpha
+ * using the equation given in Poynton's ColorFAQ at
+ * <http://www.inforamp.net/~poynton/>
+ * Copyright (c) 1998-01-04 Charles Poynton poynton at inforamp.net
+ *
+ *     Y = 0.212671 * R + 0.715160 * G + 0.072169 * B
+ *
+ *  We approximate this with
+ *
+ *     Y = 0.21268 * R    + 0.7151 * G    + 0.07217 * B
+ *
+ *  which can be expressed with integers as
+ *
+ *     Y = (6969 * R + 23434 * G + 2365 * B)/32768
+ *
+ *  The calculation is to be done in a linear colorspace.
+ *
+ *  Other integer coefficents can be used via png_set_rgb_to_gray().
+ */
+int /* PRIVATE */
+png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
+
+{
+   png_uint_32 i;
+
+   png_uint_32 row_width = row_info->width;
+   int rgb_error = 0;
+
+   png_debug(1, "in png_do_rgb_to_gray\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+      (row_info->color_type & PNG_COLOR_MASK_COLOR))
+   {
+      png_uint_32 rc = png_ptr->rgb_to_gray_red_coeff;
+      png_uint_32 gc = png_ptr->rgb_to_gray_green_coeff;
+      png_uint_32 bc = png_ptr->rgb_to_gray_blue_coeff;
+
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+      {
+         if (row_info->bit_depth == 8)
+         {
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+            if (png_ptr->gamma_from_1 != NULL && png_ptr->gamma_to_1 != NULL)
+            {
+               png_bytep sp = row;
+               png_bytep dp = row;
+
+               for (i = 0; i < row_width; i++)
+               {
+                  png_byte red   = png_ptr->gamma_to_1[*(sp++)];
+                  png_byte green = png_ptr->gamma_to_1[*(sp++)];
+                  png_byte blue  = png_ptr->gamma_to_1[*(sp++)];
+                  if(red != green || red != blue)
+                  {
+                     rgb_error |= 1;
+                     *(dp++) = png_ptr->gamma_from_1[
+                       (rc*red+gc*green+bc*blue)>>15];
+                  }
+                  else
+                     *(dp++) = *(sp-1);
+               }
+            }
+            else
+#endif
+            {
+               png_bytep sp = row;
+               png_bytep dp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  png_byte red   = *(sp++);
+                  png_byte green = *(sp++);
+                  png_byte blue  = *(sp++);
+                  if(red != green || red != blue)
+                  {
+                     rgb_error |= 1;
+                     *(dp++) = (png_byte)((rc*red+gc*green+bc*blue)>>15);
+                  }
+                  else
+                     *(dp++) = *(sp-1);
+               }
+            }
+         }
+
+         else /* RGB bit_depth == 16 */
+         {
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+            if (png_ptr->gamma_16_to_1 != NULL &&
+                png_ptr->gamma_16_from_1 != NULL)
+            {
+               png_bytep sp = row;
+               png_bytep dp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  png_uint_16 red, green, blue, w;
+
+                  red   = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  blue  = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+
+                  if(red == green && red == blue)
+                     w = red;
+                  else
+                  {
+                     png_uint_16 red_1   = png_ptr->gamma_16_to_1[(red&0xff) >>
+                                  png_ptr->gamma_shift][red>>8];
+                     png_uint_16 green_1 = png_ptr->gamma_16_to_1[(green&0xff) >>
+                                  png_ptr->gamma_shift][green>>8];
+                     png_uint_16 blue_1  = png_ptr->gamma_16_to_1[(blue&0xff) >>
+                                  png_ptr->gamma_shift][blue>>8];
+                     png_uint_16 gray16  = (png_uint_16)((rc*red_1 + gc*green_1
+                                  + bc*blue_1)>>15);
+                     w = png_ptr->gamma_16_from_1[(gray16&0xff) >>
+                         png_ptr->gamma_shift][gray16 >> 8];
+                     rgb_error |= 1;
+                  }
+
+                  *(dp++) = (png_byte)((w>>8) & 0xff);
+                  *(dp++) = (png_byte)(w & 0xff);
+               }
+            }
+            else
+#endif
+            {
+               png_bytep sp = row;
+               png_bytep dp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  png_uint_16 red, green, blue, gray16;
+
+                  red   = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  blue  = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+
+                  if(red != green || red != blue)
+                     rgb_error |= 1;
+                  gray16  = (png_uint_16)((rc*red + gc*green + bc*blue)>>15);
+                  *(dp++) = (png_byte)((gray16>>8) & 0xff);
+                  *(dp++) = (png_byte)(gray16 & 0xff);
+               }
+            }
+         }
+      }
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+      {
+         if (row_info->bit_depth == 8)
+         {
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+            if (png_ptr->gamma_from_1 != NULL && png_ptr->gamma_to_1 != NULL)
+            {
+               png_bytep sp = row;
+               png_bytep dp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  png_byte red   = png_ptr->gamma_to_1[*(sp++)];
+                  png_byte green = png_ptr->gamma_to_1[*(sp++)];
+                  png_byte blue  = png_ptr->gamma_to_1[*(sp++)];
+                  if(red != green || red != blue)
+                     rgb_error |= 1;
+                  *(dp++) =  png_ptr->gamma_from_1
+                             [(rc*red + gc*green + bc*blue)>>15];
+                  *(dp++) = *(sp++);  /* alpha */
+               }
+            }
+            else
+#endif
+            {
+               png_bytep sp = row;
+               png_bytep dp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  png_byte red   = *(sp++);
+                  png_byte green = *(sp++);
+                  png_byte blue  = *(sp++);
+                  if(red != green || red != blue)
+                     rgb_error |= 1;
+                  *(dp++) =  (png_byte)((rc*red + gc*green + bc*blue)>>15);
+                  *(dp++) = *(sp++);  /* alpha */
+               }
+            }
+         }
+         else /* RGBA bit_depth == 16 */
+         {
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+            if (png_ptr->gamma_16_to_1 != NULL &&
+                png_ptr->gamma_16_from_1 != NULL)
+            {
+               png_bytep sp = row;
+               png_bytep dp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  png_uint_16 red, green, blue, w;
+
+                  red   = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  blue  = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+
+                  if(red == green && red == blue)
+                     w = red;
+                  else
+                  {
+                     png_uint_16 red_1   = png_ptr->gamma_16_to_1[(red&0xff) >>
+                                  png_ptr->gamma_shift][red>>8];
+                     png_uint_16 green_1 = png_ptr->gamma_16_to_1[(green&0xff) >>
+                                  png_ptr->gamma_shift][green>>8];
+                     png_uint_16 blue_1  = png_ptr->gamma_16_to_1[(blue&0xff) >>
+                                  png_ptr->gamma_shift][blue>>8];
+                     png_uint_16 gray16  = (png_uint_16)((rc * red_1
+                                  + gc * green_1 + bc * blue_1)>>15);
+                     w = png_ptr->gamma_16_from_1[(gray16&0xff) >>
+                         png_ptr->gamma_shift][gray16 >> 8];
+                     rgb_error |= 1;
+                  }
+
+                  *(dp++) = (png_byte)((w>>8) & 0xff);
+                  *(dp++) = (png_byte)(w & 0xff);
+                  *(dp++) = *(sp++);  /* alpha */
+                  *(dp++) = *(sp++);
+               }
+            }
+            else
+#endif
+            {
+               png_bytep sp = row;
+               png_bytep dp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  png_uint_16 red, green, blue, gray16;
+                  red   = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2;
+                  green = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2;
+                  blue  = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2;
+                  if(red != green || red != blue)
+                     rgb_error |= 1;
+                  gray16  = (png_uint_16)((rc*red + gc*green + bc*blue)>>15);
+                  *(dp++) = (png_byte)((gray16>>8) & 0xff);
+                  *(dp++) = (png_byte)(gray16 & 0xff);
+                  *(dp++) = *(sp++);  /* alpha */
+                  *(dp++) = *(sp++);
+               }
+            }
+         }
+      }
+   row_info->channels -= (png_byte)2;
+      row_info->color_type &= ~PNG_COLOR_MASK_COLOR;
+      row_info->pixel_depth = (png_byte)(row_info->channels *
+         row_info->bit_depth);
+      row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+   }
+   return rgb_error;
+}
+#endif
+
+/* Build a grayscale palette.  Palette is assumed to be 1 << bit_depth
+ * large of png_color.  This lets grayscale images be treated as
+ * paletted.  Most useful for gamma correction and simplification
+ * of code.
+ */
+void PNGAPI
+png_build_grayscale_palette(int bit_depth, png_colorp palette)
+{
+   int num_palette;
+   int color_inc;
+   int i;
+   int v;
+
+   png_debug(1, "in png_do_build_grayscale_palette\n");
+   if (palette == NULL)
+      return;
+
+   switch (bit_depth)
+   {
+      case 1:
+         num_palette = 2;
+         color_inc = 0xff;
+         break;
+      case 2:
+         num_palette = 4;
+         color_inc = 0x55;
+         break;
+      case 4:
+         num_palette = 16;
+         color_inc = 0x11;
+         break;
+      case 8:
+         num_palette = 256;
+         color_inc = 1;
+         break;
+      default:
+         num_palette = 0;
+         color_inc = 0;
+         break;
+   }
+
+   for (i = 0, v = 0; i < num_palette; i++, v += color_inc)
+   {
+      palette[i].red = (png_byte)v;
+      palette[i].green = (png_byte)v;
+      palette[i].blue = (png_byte)v;
+   }
+}
+
+/* This function is currently unused.  Do we really need it? */
+#if defined(PNG_READ_DITHER_SUPPORTED) && defined(PNG_CORRECT_PALETTE_SUPPORTED)
+void /* PRIVATE */
+png_correct_palette(png_structp png_ptr, png_colorp palette,
+   int num_palette)
+{
+   png_debug(1, "in png_correct_palette\n");
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \
+    defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
+   if (png_ptr->transformations & (PNG_GAMMA | PNG_BACKGROUND))
+   {
+      png_color back, back_1;
+
+      if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_FILE)
+      {
+         back.red = png_ptr->gamma_table[png_ptr->background.red];
+         back.green = png_ptr->gamma_table[png_ptr->background.green];
+         back.blue = png_ptr->gamma_table[png_ptr->background.blue];
+
+         back_1.red = png_ptr->gamma_to_1[png_ptr->background.red];
+         back_1.green = png_ptr->gamma_to_1[png_ptr->background.green];
+         back_1.blue = png_ptr->gamma_to_1[png_ptr->background.blue];
+      }
+      else
+      {
+         double g;
+
+         g = 1.0 / (png_ptr->background_gamma * png_ptr->screen_gamma);
+
+         if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_SCREEN ||
+             fabs(g - 1.0) < PNG_GAMMA_THRESHOLD)
+         {
+            back.red = png_ptr->background.red;
+            back.green = png_ptr->background.green;
+            back.blue = png_ptr->background.blue;
+         }
+         else
+         {
+            back.red =
+               (png_byte)(pow((double)png_ptr->background.red/255, g) *
+                255.0 + 0.5);
+            back.green =
+               (png_byte)(pow((double)png_ptr->background.green/255, g) *
+                255.0 + 0.5);
+            back.blue =
+               (png_byte)(pow((double)png_ptr->background.blue/255, g) *
+                255.0 + 0.5);
+         }
+
+         g = 1.0 / png_ptr->background_gamma;
+
+         back_1.red =
+            (png_byte)(pow((double)png_ptr->background.red/255, g) *
+             255.0 + 0.5);
+         back_1.green =
+            (png_byte)(pow((double)png_ptr->background.green/255, g) *
+             255.0 + 0.5);
+         back_1.blue =
+            (png_byte)(pow((double)png_ptr->background.blue/255, g) *
+             255.0 + 0.5);
+      }
+
+      if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      {
+         png_uint_32 i;
+
+         for (i = 0; i < (png_uint_32)num_palette; i++)
+         {
+            if (i < png_ptr->num_trans && png_ptr->trans[i] == 0)
+            {
+               palette[i] = back;
+            }
+            else if (i < png_ptr->num_trans && png_ptr->trans[i] != 0xff)
+            {
+               png_byte v, w;
+
+               v = png_ptr->gamma_to_1[png_ptr->palette[i].red];
+               png_composite(w, v, png_ptr->trans[i], back_1.red);
+               palette[i].red = png_ptr->gamma_from_1[w];
+
+               v = png_ptr->gamma_to_1[png_ptr->palette[i].green];
+               png_composite(w, v, png_ptr->trans[i], back_1.green);
+               palette[i].green = png_ptr->gamma_from_1[w];
+
+               v = png_ptr->gamma_to_1[png_ptr->palette[i].blue];
+               png_composite(w, v, png_ptr->trans[i], back_1.blue);
+               palette[i].blue = png_ptr->gamma_from_1[w];
+            }
+            else
+            {
+               palette[i].red = png_ptr->gamma_table[palette[i].red];
+               palette[i].green = png_ptr->gamma_table[palette[i].green];
+               palette[i].blue = png_ptr->gamma_table[palette[i].blue];
+            }
+         }
+      }
+      else
+      {
+         int i;
+
+         for (i = 0; i < num_palette; i++)
+         {
+            if (palette[i].red == (png_byte)png_ptr->trans_values.gray)
+            {
+               palette[i] = back;
+            }
+            else
+            {
+               palette[i].red = png_ptr->gamma_table[palette[i].red];
+               palette[i].green = png_ptr->gamma_table[palette[i].green];
+               palette[i].blue = png_ptr->gamma_table[palette[i].blue];
+            }
+         }
+      }
+   }
+   else
+#endif
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+   if (png_ptr->transformations & PNG_GAMMA)
+   {
+      int i;
+
+      for (i = 0; i < num_palette; i++)
+      {
+         palette[i].red = png_ptr->gamma_table[palette[i].red];
+         palette[i].green = png_ptr->gamma_table[palette[i].green];
+         palette[i].blue = png_ptr->gamma_table[palette[i].blue];
+      }
+   }
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+   else
+#endif
+#endif
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+   if (png_ptr->transformations & PNG_BACKGROUND)
+   {
+      if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      {
+         png_color back;
+
+         back.red   = (png_byte)png_ptr->background.red;
+         back.green = (png_byte)png_ptr->background.green;
+         back.blue  = (png_byte)png_ptr->background.blue;
+
+         for (i = 0; i < (int)png_ptr->num_trans; i++)
+         {
+            if (png_ptr->trans[i] == 0)
+            {
+               palette[i].red = back.red;
+               palette[i].green = back.green;
+               palette[i].blue = back.blue;
+            }
+            else if (png_ptr->trans[i] != 0xff)
+            {
+               png_composite(palette[i].red, png_ptr->palette[i].red,
+                  png_ptr->trans[i], back.red);
+               png_composite(palette[i].green, png_ptr->palette[i].green,
+                  png_ptr->trans[i], back.green);
+               png_composite(palette[i].blue, png_ptr->palette[i].blue,
+                  png_ptr->trans[i], back.blue);
+            }
+         }
+      }
+      else /* assume grayscale palette (what else could it be?) */
+      {
+         int i;
+
+         for (i = 0; i < num_palette; i++)
+         {
+            if (i == (png_byte)png_ptr->trans_values.gray)
+            {
+               palette[i].red = (png_byte)png_ptr->background.red;
+               palette[i].green = (png_byte)png_ptr->background.green;
+               palette[i].blue = (png_byte)png_ptr->background.blue;
+            }
+         }
+      }
+   }
+#endif
+}
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+/* Replace any alpha or transparency with the supplied background color.
+ * "background" is already in the screen gamma, while "background_1" is
+ * at a gamma of 1.0.  Paletted files have already been taken care of.
+ */
+void /* PRIVATE */
+png_do_background(png_row_infop row_info, png_bytep row,
+   png_color_16p trans_values, png_color_16p background
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+   , png_color_16p background_1,
+   png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
+   png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
+   png_uint_16pp gamma_16_to_1, int gamma_shift
+#endif
+   )
+{
+   png_bytep sp, dp;
+   png_uint_32 i;
+   png_uint_32 row_width=row_info->width;
+   int shift;
+
+   png_debug(1, "in png_do_background\n");
+   if (background != NULL &&
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+      (!(row_info->color_type & PNG_COLOR_MASK_ALPHA) ||
+      (row_info->color_type != PNG_COLOR_TYPE_PALETTE && trans_values)))
+   {
+      switch (row_info->color_type)
+      {
+         case PNG_COLOR_TYPE_GRAY:
+         {
+            switch (row_info->bit_depth)
+            {
+               case 1:
+               {
+                  sp = row;
+                  shift = 7;
+                  for (i = 0; i < row_width; i++)
+                  {
+                     if ((png_uint_16)((*sp >> shift) & 0x01)
+                        == trans_values->gray)
+                     {
+                        *sp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff);
+                        *sp |= (png_byte)(background->gray << shift);
+                     }
+                     if (!shift)
+                     {
+                        shift = 7;
+                        sp++;
+                     }
+                     else
+                        shift--;
+                  }
+                  break;
+               }
+               case 2:
+               {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+                  if (gamma_table != NULL)
+                  {
+                     sp = row;
+                     shift = 6;
+                     for (i = 0; i < row_width; i++)
+                     {
+                        if ((png_uint_16)((*sp >> shift) & 0x03)
+                            == trans_values->gray)
+                        {
+                           *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
+                           *sp |= (png_byte)(background->gray << shift);
+                        }
+                        else
+                        {
+                           png_byte p = (png_byte)((*sp >> shift) & 0x03);
+                           png_byte g = (png_byte)((gamma_table [p | (p << 2) |
+                               (p << 4) | (p << 6)] >> 6) & 0x03);
+                           *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
+                           *sp |= (png_byte)(g << shift);
+                        }
+                        if (!shift)
+                        {
+                           shift = 6;
+                           sp++;
+                        }
+                        else
+                           shift -= 2;
+                     }
+                  }
+                  else
+#endif
+                  {
+                     sp = row;
+                     shift = 6;
+                     for (i = 0; i < row_width; i++)
+                     {
+                        if ((png_uint_16)((*sp >> shift) & 0x03)
+                            == trans_values->gray)
+                        {
+                           *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
+                           *sp |= (png_byte)(background->gray << shift);
+                        }
+                        if (!shift)
+                        {
+                           shift = 6;
+                           sp++;
+                        }
+                        else
+                           shift -= 2;
+                     }
+                  }
+                  break;
+               }
+               case 4:
+               {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+                  if (gamma_table != NULL)
+                  {
+                     sp = row;
+                     shift = 4;
+                     for (i = 0; i < row_width; i++)
+                     {
+                        if ((png_uint_16)((*sp >> shift) & 0x0f)
+                            == trans_values->gray)
+                        {
+                           *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
+                           *sp |= (png_byte)(background->gray << shift);
+                        }
+                        else
+                        {
+                           png_byte p = (png_byte)((*sp >> shift) & 0x0f);
+                           png_byte g = (png_byte)((gamma_table[p |
+                             (p << 4)] >> 4) & 0x0f);
+                           *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
+                           *sp |= (png_byte)(g << shift);
+                        }
+                        if (!shift)
+                        {
+                           shift = 4;
+                           sp++;
+                        }
+                        else
+                           shift -= 4;
+                     }
+                  }
+                  else
+#endif
+                  {
+                     sp = row;
+                     shift = 4;
+                     for (i = 0; i < row_width; i++)
+                     {
+                        if ((png_uint_16)((*sp >> shift) & 0x0f)
+                            == trans_values->gray)
+                        {
+                           *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
+                           *sp |= (png_byte)(background->gray << shift);
+                        }
+                        if (!shift)
+                        {
+                           shift = 4;
+                           sp++;
+                        }
+                        else
+                           shift -= 4;
+                     }
+                  }
+                  break;
+               }
+               case 8:
+               {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+                  if (gamma_table != NULL)
+                  {
+                     sp = row;
+                     for (i = 0; i < row_width; i++, sp++)
+                     {
+                        if (*sp == trans_values->gray)
+                        {
+                           *sp = (png_byte)background->gray;
+                        }
+                        else
+                        {
+                           *sp = gamma_table[*sp];
+                        }
+                     }
+                  }
+                  else
+#endif
+                  {
+                     sp = row;
+                     for (i = 0; i < row_width; i++, sp++)
+                     {
+                        if (*sp == trans_values->gray)
+                        {
+                           *sp = (png_byte)background->gray;
+                        }
+                     }
+                  }
+                  break;
+               }
+               case 16:
+               {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+                  if (gamma_16 != NULL)
+                  {
+                     sp = row;
+                     for (i = 0; i < row_width; i++, sp += 2)
+                     {
+                        png_uint_16 v;
+
+                        v = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+                        if (v == trans_values->gray)
+                        {
+                           /* background is already in screen gamma */
+                           *sp = (png_byte)((background->gray >> 8) & 0xff);
+                           *(sp + 1) = (png_byte)(background->gray & 0xff);
+                        }
+                        else
+                        {
+                           v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
+                           *sp = (png_byte)((v >> 8) & 0xff);
+                           *(sp + 1) = (png_byte)(v & 0xff);
+                        }
+                     }
+                  }
+                  else
+#endif
+                  {
+                     sp = row;
+                     for (i = 0; i < row_width; i++, sp += 2)
+                     {
+                        png_uint_16 v;
+
+                        v = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+                        if (v == trans_values->gray)
+                        {
+                           *sp = (png_byte)((background->gray >> 8) & 0xff);
+                           *(sp + 1) = (png_byte)(background->gray & 0xff);
+                        }
+                     }
+                  }
+                  break;
+               }
+            }
+            break;
+         }
+         case PNG_COLOR_TYPE_RGB:
+         {
+            if (row_info->bit_depth == 8)
+            {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+               if (gamma_table != NULL)
+               {
+                  sp = row;
+                  for (i = 0; i < row_width; i++, sp += 3)
+                  {
+                     if (*sp == trans_values->red &&
+                        *(sp + 1) == trans_values->green &&
+                        *(sp + 2) == trans_values->blue)
+                     {
+                        *sp = (png_byte)background->red;
+                        *(sp + 1) = (png_byte)background->green;
+                        *(sp + 2) = (png_byte)background->blue;
+                     }
+                     else
+                     {
+                        *sp = gamma_table[*sp];
+                        *(sp + 1) = gamma_table[*(sp + 1)];
+                        *(sp + 2) = gamma_table[*(sp + 2)];
+                     }
+                  }
+               }
+               else
+#endif
+               {
+                  sp = row;
+                  for (i = 0; i < row_width; i++, sp += 3)
+                  {
+                     if (*sp == trans_values->red &&
+                        *(sp + 1) == trans_values->green &&
+                        *(sp + 2) == trans_values->blue)
+                     {
+                        *sp = (png_byte)background->red;
+                        *(sp + 1) = (png_byte)background->green;
+                        *(sp + 2) = (png_byte)background->blue;
+                     }
+                  }
+               }
+            }
+            else /* if (row_info->bit_depth == 16) */
+            {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+               if (gamma_16 != NULL)
+               {
+                  sp = row;
+                  for (i = 0; i < row_width; i++, sp += 6)
+                  {
+                     png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+                     png_uint_16 g = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
+                     png_uint_16 b = (png_uint_16)(((*(sp+4)) << 8) + *(sp+5));
+                     if (r == trans_values->red && g == trans_values->green &&
+                        b == trans_values->blue)
+                     {
+                        /* background is already in screen gamma */
+                        *sp = (png_byte)((background->red >> 8) & 0xff);
+                        *(sp + 1) = (png_byte)(background->red & 0xff);
+                        *(sp + 2) = (png_byte)((background->green >> 8) & 0xff);
+                        *(sp + 3) = (png_byte)(background->green & 0xff);
+                        *(sp + 4) = (png_byte)((background->blue >> 8) & 0xff);
+                        *(sp + 5) = (png_byte)(background->blue & 0xff);
+                     }
+                     else
+                     {
+                        png_uint_16 v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
+                        *sp = (png_byte)((v >> 8) & 0xff);
+                        *(sp + 1) = (png_byte)(v & 0xff);
+                        v = gamma_16[*(sp + 3) >> gamma_shift][*(sp + 2)];
+                        *(sp + 2) = (png_byte)((v >> 8) & 0xff);
+                        *(sp + 3) = (png_byte)(v & 0xff);
+                        v = gamma_16[*(sp + 5) >> gamma_shift][*(sp + 4)];
+                        *(sp + 4) = (png_byte)((v >> 8) & 0xff);
+                        *(sp + 5) = (png_byte)(v & 0xff);
+                     }
+                  }
+               }
+               else
+#endif
+               {
+                  sp = row;
+                  for (i = 0; i < row_width; i++, sp += 6)
+                  {
+                     png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp+1));
+                     png_uint_16 g = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
+                     png_uint_16 b = (png_uint_16)(((*(sp+4)) << 8) + *(sp+5));
+
+                     if (r == trans_values->red && g == trans_values->green &&
+                        b == trans_values->blue)
+                     {
+                        *sp = (png_byte)((background->red >> 8) & 0xff);
+                        *(sp + 1) = (png_byte)(background->red & 0xff);
+                        *(sp + 2) = (png_byte)((background->green >> 8) & 0xff);
+                        *(sp + 3) = (png_byte)(background->green & 0xff);
+                        *(sp + 4) = (png_byte)((background->blue >> 8) & 0xff);
+                        *(sp + 5) = (png_byte)(background->blue & 0xff);
+                     }
+                  }
+               }
+            }
+            break;
+         }
+         case PNG_COLOR_TYPE_GRAY_ALPHA:
+         {
+            if (row_info->bit_depth == 8)
+            {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+               if (gamma_to_1 != NULL && gamma_from_1 != NULL &&
+                   gamma_table != NULL)
+               {
+                  sp = row;
+                  dp = row;
+                  for (i = 0; i < row_width; i++, sp += 2, dp++)
+                  {
+                     png_uint_16 a = *(sp + 1);
+
+                     if (a == 0xff)
+                     {
+                        *dp = gamma_table[*sp];
+                     }
+                     else if (a == 0)
+                     {
+                        /* background is already in screen gamma */
+                        *dp = (png_byte)background->gray;
+                     }
+                     else
+                     {
+                        png_byte v, w;
+
+                        v = gamma_to_1[*sp];
+                        png_composite(w, v, a, background_1->gray);
+                        *dp = gamma_from_1[w];
+                     }
+                  }
+               }
+               else
+#endif
+               {
+                  sp = row;
+                  dp = row;
+                  for (i = 0; i < row_width; i++, sp += 2, dp++)
+                  {
+                     png_byte a = *(sp + 1);
+
+                     if (a == 0xff)
+                     {
+                        *dp = *sp;
+                     }
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+                     else if (a == 0)
+                     {
+                        *dp = (png_byte)background->gray;
+                     }
+                     else
+                     {
+                        png_composite(*dp, *sp, a, background_1->gray);
+                     }
+#else
+                     *dp = (png_byte)background->gray;
+#endif
+                  }
+               }
+            }
+            else /* if (png_ptr->bit_depth == 16) */
+            {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+               if (gamma_16 != NULL && gamma_16_from_1 != NULL &&
+                   gamma_16_to_1 != NULL)
+               {
+                  sp = row;
+                  dp = row;
+                  for (i = 0; i < row_width; i++, sp += 4, dp += 2)
+                  {
+                     png_uint_16 a = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
+
+                     if (a == (png_uint_16)0xffff)
+                     {
+                        png_uint_16 v;
+
+                        v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
+                        *dp = (png_byte)((v >> 8) & 0xff);
+                        *(dp + 1) = (png_byte)(v & 0xff);
+                     }
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+                     else if (a == 0)
+#else
+                     else
+#endif
+                     {
+                        /* background is already in screen gamma */
+                        *dp = (png_byte)((background->gray >> 8) & 0xff);
+                        *(dp + 1) = (png_byte)(background->gray & 0xff);
+                     }
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+                     else
+                     {
+                        png_uint_16 g, v, w;
+
+                        g = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp];
+                        png_composite_16(v, g, a, background_1->gray);
+                        w = gamma_16_from_1[(v&0xff) >> gamma_shift][v >> 8];
+                        *dp = (png_byte)((w >> 8) & 0xff);
+                        *(dp + 1) = (png_byte)(w & 0xff);
+                     }
+#endif
+                  }
+               }
+               else
+#endif
+               {
+                  sp = row;
+                  dp = row;
+                  for (i = 0; i < row_width; i++, sp += 4, dp += 2)
+                  {
+                     png_uint_16 a = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
+                     if (a == (png_uint_16)0xffff)
+                     {
+                        png_memcpy(dp, sp, 2);
+                     }
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+                     else if (a == 0)
+#else
+                     else
+#endif
+                     {
+                        *dp = (png_byte)((background->gray >> 8) & 0xff);
+                        *(dp + 1) = (png_byte)(background->gray & 0xff);
+                     }
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+                     else
+                     {
+                        png_uint_16 g, v;
+
+                        g = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+                        png_composite_16(v, g, a, background_1->gray);
+                        *dp = (png_byte)((v >> 8) & 0xff);
+                        *(dp + 1) = (png_byte)(v & 0xff);
+                     }
+#endif
+                  }
+               }
+            }
+            break;
+         }
+         case PNG_COLOR_TYPE_RGB_ALPHA:
+         {
+            if (row_info->bit_depth == 8)
+            {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+               if (gamma_to_1 != NULL && gamma_from_1 != NULL &&
+                   gamma_table != NULL)
+               {
+                  sp = row;
+                  dp = row;
+                  for (i = 0; i < row_width; i++, sp += 4, dp += 3)
+                  {
+                     png_byte a = *(sp + 3);
+
+                     if (a == 0xff)
+                     {
+                        *dp = gamma_table[*sp];
+                        *(dp + 1) = gamma_table[*(sp + 1)];
+                        *(dp + 2) = gamma_table[*(sp + 2)];
+                     }
+                     else if (a == 0)
+                     {
+                        /* background is already in screen gamma */
+                        *dp = (png_byte)background->red;
+                        *(dp + 1) = (png_byte)background->green;
+                        *(dp + 2) = (png_byte)background->blue;
+                     }
+                     else
+                     {
+                        png_byte v, w;
+
+                        v = gamma_to_1[*sp];
+                        png_composite(w, v, a, background_1->red);
+                        *dp = gamma_from_1[w];
+                        v = gamma_to_1[*(sp + 1)];
+                        png_composite(w, v, a, background_1->green);
+                        *(dp + 1) = gamma_from_1[w];
+                        v = gamma_to_1[*(sp + 2)];
+                        png_composite(w, v, a, background_1->blue);
+                        *(dp + 2) = gamma_from_1[w];
+                     }
+                  }
+               }
+               else
+#endif
+               {
+                  sp = row;
+                  dp = row;
+                  for (i = 0; i < row_width; i++, sp += 4, dp += 3)
+                  {
+                     png_byte a = *(sp + 3);
+
+                     if (a == 0xff)
+                     {
+                        *dp = *sp;
+                        *(dp + 1) = *(sp + 1);
+                        *(dp + 2) = *(sp + 2);
+                     }
+                     else if (a == 0)
+                     {
+                        *dp = (png_byte)background->red;
+                        *(dp + 1) = (png_byte)background->green;
+                        *(dp + 2) = (png_byte)background->blue;
+                     }
+                     else
+                     {
+                        png_composite(*dp, *sp, a, background->red);
+                        png_composite(*(dp + 1), *(sp + 1), a,
+                           background->green);
+                        png_composite(*(dp + 2), *(sp + 2), a,
+                           background->blue);
+                     }
+                  }
+               }
+            }
+            else /* if (row_info->bit_depth == 16) */
+            {
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+               if (gamma_16 != NULL && gamma_16_from_1 != NULL &&
+                   gamma_16_to_1 != NULL)
+               {
+                  sp = row;
+                  dp = row;
+                  for (i = 0; i < row_width; i++, sp += 8, dp += 6)
+                  {
+                     png_uint_16 a = (png_uint_16)(((png_uint_16)(*(sp + 6))
+                         << 8) + (png_uint_16)(*(sp + 7)));
+                     if (a == (png_uint_16)0xffff)
+                     {
+                        png_uint_16 v;
+
+                        v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
+                        *dp = (png_byte)((v >> 8) & 0xff);
+                        *(dp + 1) = (png_byte)(v & 0xff);
+                        v = gamma_16[*(sp + 3) >> gamma_shift][*(sp + 2)];
+                        *(dp + 2) = (png_byte)((v >> 8) & 0xff);
+                        *(dp + 3) = (png_byte)(v & 0xff);
+                        v = gamma_16[*(sp + 5) >> gamma_shift][*(sp + 4)];
+                        *(dp + 4) = (png_byte)((v >> 8) & 0xff);
+                        *(dp + 5) = (png_byte)(v & 0xff);
+                     }
+                     else if (a == 0)
+                     {
+                        /* background is already in screen gamma */
+                        *dp = (png_byte)((background->red >> 8) & 0xff);
+                        *(dp + 1) = (png_byte)(background->red & 0xff);
+                        *(dp + 2) = (png_byte)((background->green >> 8) & 0xff);
+                        *(dp + 3) = (png_byte)(background->green & 0xff);
+                        *(dp + 4) = (png_byte)((background->blue >> 8) & 0xff);
+                        *(dp + 5) = (png_byte)(background->blue & 0xff);
+                     }
+                     else
+                     {
+                        png_uint_16 v, w, x;
+
+                        v = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp];
+                        png_composite_16(w, v, a, background_1->red);
+                        x = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8];
+                        *dp = (png_byte)((x >> 8) & 0xff);
+                        *(dp + 1) = (png_byte)(x & 0xff);
+                        v = gamma_16_to_1[*(sp + 3) >> gamma_shift][*(sp + 2)];
+                        png_composite_16(w, v, a, background_1->green);
+                        x = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8];
+                        *(dp + 2) = (png_byte)((x >> 8) & 0xff);
+                        *(dp + 3) = (png_byte)(x & 0xff);
+                        v = gamma_16_to_1[*(sp + 5) >> gamma_shift][*(sp + 4)];
+                        png_composite_16(w, v, a, background_1->blue);
+                        x = gamma_16_from_1[(w & 0xff) >> gamma_shift][w >> 8];
+                        *(dp + 4) = (png_byte)((x >> 8) & 0xff);
+                        *(dp + 5) = (png_byte)(x & 0xff);
+                     }
+                  }
+               }
+               else
+#endif
+               {
+                  sp = row;
+                  dp = row;
+                  for (i = 0; i < row_width; i++, sp += 8, dp += 6)
+                  {
+                     png_uint_16 a = (png_uint_16)(((png_uint_16)(*(sp + 6))
+                        << 8) + (png_uint_16)(*(sp + 7)));
+                     if (a == (png_uint_16)0xffff)
+                     {
+                        png_memcpy(dp, sp, 6);
+                     }
+                     else if (a == 0)
+                     {
+                        *dp = (png_byte)((background->red >> 8) & 0xff);
+                        *(dp + 1) = (png_byte)(background->red & 0xff);
+                        *(dp + 2) = (png_byte)((background->green >> 8) & 0xff);
+                        *(dp + 3) = (png_byte)(background->green & 0xff);
+                        *(dp + 4) = (png_byte)((background->blue >> 8) & 0xff);
+                        *(dp + 5) = (png_byte)(background->blue & 0xff);
+                     }
+                     else
+                     {
+                        png_uint_16 v;
+
+                        png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+                        png_uint_16 g = (png_uint_16)(((*(sp + 2)) << 8)
+                            + *(sp + 3));
+                        png_uint_16 b = (png_uint_16)(((*(sp + 4)) << 8)
+                            + *(sp + 5));
+
+                        png_composite_16(v, r, a, background->red);
+                        *dp = (png_byte)((v >> 8) & 0xff);
+                        *(dp + 1) = (png_byte)(v & 0xff);
+                        png_composite_16(v, g, a, background->green);
+                        *(dp + 2) = (png_byte)((v >> 8) & 0xff);
+                        *(dp + 3) = (png_byte)(v & 0xff);
+                        png_composite_16(v, b, a, background->blue);
+                        *(dp + 4) = (png_byte)((v >> 8) & 0xff);
+                        *(dp + 5) = (png_byte)(v & 0xff);
+                     }
+                  }
+               }
+            }
+            break;
+         }
+      }
+
+      if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
+      {
+         row_info->color_type &= ~PNG_COLOR_MASK_ALPHA;
+         row_info->channels--;
+         row_info->pixel_depth = (png_byte)(row_info->channels *
+            row_info->bit_depth);
+         row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+      }
+   }
+}
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+/* Gamma correct the image, avoiding the alpha channel.  Make sure
+ * you do this after you deal with the transparency issue on grayscale
+ * or RGB images. If your bit depth is 8, use gamma_table, if it
+ * is 16, use gamma_16_table and gamma_shift.  Build these with
+ * build_gamma_table().
+ */
+void /* PRIVATE */
+png_do_gamma(png_row_infop row_info, png_bytep row,
+   png_bytep gamma_table, png_uint_16pp gamma_16_table,
+   int gamma_shift)
+{
+   png_bytep sp;
+   png_uint_32 i;
+   png_uint_32 row_width=row_info->width;
+
+   png_debug(1, "in png_do_gamma\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+       ((row_info->bit_depth <= 8 && gamma_table != NULL) ||
+        (row_info->bit_depth == 16 && gamma_16_table != NULL)))
+   {
+      switch (row_info->color_type)
+      {
+         case PNG_COLOR_TYPE_RGB:
+         {
+            if (row_info->bit_depth == 8)
+            {
+               sp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  *sp = gamma_table[*sp];
+                  sp++;
+                  *sp = gamma_table[*sp];
+                  sp++;
+                  *sp = gamma_table[*sp];
+                  sp++;
+               }
+            }
+            else /* if (row_info->bit_depth == 16) */
+            {
+               sp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  png_uint_16 v;
+
+                  v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+                  *sp = (png_byte)((v >> 8) & 0xff);
+                  *(sp + 1) = (png_byte)(v & 0xff);
+                  sp += 2;
+                  v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+                  *sp = (png_byte)((v >> 8) & 0xff);
+                  *(sp + 1) = (png_byte)(v & 0xff);
+                  sp += 2;
+                  v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+                  *sp = (png_byte)((v >> 8) & 0xff);
+                  *(sp + 1) = (png_byte)(v & 0xff);
+                  sp += 2;
+               }
+            }
+            break;
+         }
+         case PNG_COLOR_TYPE_RGB_ALPHA:
+         {
+            if (row_info->bit_depth == 8)
+            {
+               sp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  *sp = gamma_table[*sp];
+                  sp++;
+                  *sp = gamma_table[*sp];
+                  sp++;
+                  *sp = gamma_table[*sp];
+                  sp++;
+                  sp++;
+               }
+            }
+            else /* if (row_info->bit_depth == 16) */
+            {
+               sp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+                  *sp = (png_byte)((v >> 8) & 0xff);
+                  *(sp + 1) = (png_byte)(v & 0xff);
+                  sp += 2;
+                  v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+                  *sp = (png_byte)((v >> 8) & 0xff);
+                  *(sp + 1) = (png_byte)(v & 0xff);
+                  sp += 2;
+                  v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+                  *sp = (png_byte)((v >> 8) & 0xff);
+                  *(sp + 1) = (png_byte)(v & 0xff);
+                  sp += 4;
+               }
+            }
+            break;
+         }
+         case PNG_COLOR_TYPE_GRAY_ALPHA:
+         {
+            if (row_info->bit_depth == 8)
+            {
+               sp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  *sp = gamma_table[*sp];
+                  sp += 2;
+               }
+            }
+            else /* if (row_info->bit_depth == 16) */
+            {
+               sp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+                  *sp = (png_byte)((v >> 8) & 0xff);
+                  *(sp + 1) = (png_byte)(v & 0xff);
+                  sp += 4;
+               }
+            }
+            break;
+         }
+         case PNG_COLOR_TYPE_GRAY:
+         {
+            if (row_info->bit_depth == 2)
+            {
+               sp = row;
+               for (i = 0; i < row_width; i += 4)
+               {
+                  int a = *sp & 0xc0;
+                  int b = *sp & 0x30;
+                  int c = *sp & 0x0c;
+                  int d = *sp & 0x03;
+
+                  *sp = (png_byte)(
+                        ((((int)gamma_table[a|(a>>2)|(a>>4)|(a>>6)])   ) & 0xc0)|
+                        ((((int)gamma_table[(b<<2)|b|(b>>2)|(b>>4)])>>2) & 0x30)|
+                        ((((int)gamma_table[(c<<4)|(c<<2)|c|(c>>2)])>>4) & 0x0c)|
+                        ((((int)gamma_table[(d<<6)|(d<<4)|(d<<2)|d])>>6) ));
+                  sp++;
+               }
+            }
+            if (row_info->bit_depth == 4)
+            {
+               sp = row;
+               for (i = 0; i < row_width; i += 2)
+               {
+                  int msb = *sp & 0xf0;
+                  int lsb = *sp & 0x0f;
+
+                  *sp = (png_byte)((((int)gamma_table[msb | (msb >> 4)]) & 0xf0)
+                          | (((int)gamma_table[(lsb << 4) | lsb]) >> 4));
+                  sp++;
+               }
+            }
+            else if (row_info->bit_depth == 8)
+            {
+               sp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  *sp = gamma_table[*sp];
+                  sp++;
+               }
+            }
+            else if (row_info->bit_depth == 16)
+            {
+               sp = row;
+               for (i = 0; i < row_width; i++)
+               {
+                  png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
+                  *sp = (png_byte)((v >> 8) & 0xff);
+                  *(sp + 1) = (png_byte)(v & 0xff);
+                  sp += 2;
+               }
+            }
+            break;
+         }
+      }
+   }
+}
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+/* Expands a palette row to an RGB or RGBA row depending
+ * upon whether you supply trans and num_trans.
+ */
+void /* PRIVATE */
+png_do_expand_palette(png_row_infop row_info, png_bytep row,
+   png_colorp palette, png_bytep trans, int num_trans)
+{
+   int shift, value;
+   png_bytep sp, dp;
+   png_uint_32 i;
+   png_uint_32 row_width=row_info->width;
+
+   png_debug(1, "in png_do_expand_palette\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+       row_info->color_type == PNG_COLOR_TYPE_PALETTE)
+   {
+      if (row_info->bit_depth < 8)
+      {
+         switch (row_info->bit_depth)
+         {
+            case 1:
+            {
+               sp = row + (png_size_t)((row_width - 1) >> 3);
+               dp = row + (png_size_t)row_width - 1;
+               shift = 7 - (int)((row_width + 7) & 0x07);
+               for (i = 0; i < row_width; i++)
+               {
+                  if ((*sp >> shift) & 0x01)
+                     *dp = 1;
+                  else
+                     *dp = 0;
+                  if (shift == 7)
+                  {
+                     shift = 0;
+                     sp--;
+                  }
+                  else
+                     shift++;
+
+                  dp--;
+               }
+               break;
+            }
+            case 2:
+            {
+               sp = row + (png_size_t)((row_width - 1) >> 2);
+               dp = row + (png_size_t)row_width - 1;
+               shift = (int)((3 - ((row_width + 3) & 0x03)) << 1);
+               for (i = 0; i < row_width; i++)
+               {
+                  value = (*sp >> shift) & 0x03;
+                  *dp = (png_byte)value;
+                  if (shift == 6)
+                  {
+                     shift = 0;
+                     sp--;
+                  }
+                  else
+                     shift += 2;
+
+                  dp--;
+               }
+               break;
+            }
+            case 4:
+            {
+               sp = row + (png_size_t)((row_width - 1) >> 1);
+               dp = row + (png_size_t)row_width - 1;
+               shift = (int)((row_width & 0x01) << 2);
+               for (i = 0; i < row_width; i++)
+               {
+                  value = (*sp >> shift) & 0x0f;
+                  *dp = (png_byte)value;
+                  if (shift == 4)
+                  {
+                     shift = 0;
+                     sp--;
+                  }
+                  else
+                     shift += 4;
+
+                  dp--;
+               }
+               break;
+            }
+         }
+         row_info->bit_depth = 8;
+         row_info->pixel_depth = 8;
+         row_info->rowbytes = row_width;
+      }
+      switch (row_info->bit_depth)
+      {
+         case 8:
+         {
+            if (trans != NULL)
+            {
+               sp = row + (png_size_t)row_width - 1;
+               dp = row + (png_size_t)(row_width << 2) - 1;
+
+               for (i = 0; i < row_width; i++)
+               {
+                  if ((int)(*sp) >= num_trans)
+                     *dp-- = 0xff;
+                  else
+                     *dp-- = trans[*sp];
+                  *dp-- = palette[*sp].blue;
+                  *dp-- = palette[*sp].green;
+                  *dp-- = palette[*sp].red;
+                  sp--;
+               }
+               row_info->bit_depth = 8;
+               row_info->pixel_depth = 32;
+               row_info->rowbytes = row_width * 4;
+               row_info->color_type = 6;
+               row_info->channels = 4;
+            }
+            else
+            {
+               sp = row + (png_size_t)row_width - 1;
+               dp = row + (png_size_t)(row_width * 3) - 1;
+
+               for (i = 0; i < row_width; i++)
+               {
+                  *dp-- = palette[*sp].blue;
+                  *dp-- = palette[*sp].green;
+                  *dp-- = palette[*sp].red;
+                  sp--;
+               }
+               row_info->bit_depth = 8;
+               row_info->pixel_depth = 24;
+               row_info->rowbytes = row_width * 3;
+               row_info->color_type = 2;
+               row_info->channels = 3;
+            }
+            break;
+         }
+      }
+   }
+}
+
+/* If the bit depth < 8, it is expanded to 8.  Also, if the
+ * transparency value is supplied, an alpha channel is built.
+ */
+void /* PRIVATE */
+png_do_expand(png_row_infop row_info, png_bytep row,
+   png_color_16p trans_value)
+{
+   int shift, value;
+   png_bytep sp, dp;
+   png_uint_32 i;
+   png_uint_32 row_width=row_info->width;
+
+   png_debug(1, "in png_do_expand\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL)
+#endif
+   {
+      if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
+      {
+         png_uint_16 gray = (png_uint_16)(trans_value ? trans_value->gray : 0);
+
+         if (row_info->bit_depth < 8)
+         {
+            switch (row_info->bit_depth)
+            {
+               case 1:
+               {
+                  gray = (png_uint_16)(gray*0xff);
+                  sp = row + (png_size_t)((row_width - 1) >> 3);
+                  dp = row + (png_size_t)row_width - 1;
+                  shift = 7 - (int)((row_width + 7) & 0x07);
+                  for (i = 0; i < row_width; i++)
+                  {
+                     if ((*sp >> shift) & 0x01)
+                        *dp = 0xff;
+                     else
+                        *dp = 0;
+                     if (shift == 7)
+                     {
+                        shift = 0;
+                        sp--;
+                     }
+                     else
+                        shift++;
+
+                     dp--;
+                  }
+                  break;
+               }
+               case 2:
+               {
+                  gray = (png_uint_16)(gray*0x55);
+                  sp = row + (png_size_t)((row_width - 1) >> 2);
+                  dp = row + (png_size_t)row_width - 1;
+                  shift = (int)((3 - ((row_width + 3) & 0x03)) << 1);
+                  for (i = 0; i < row_width; i++)
+                  {
+                     value = (*sp >> shift) & 0x03;
+                     *dp = (png_byte)(value | (value << 2) | (value << 4) |
+                        (value << 6));
+                     if (shift == 6)
+                     {
+                        shift = 0;
+                        sp--;
+                     }
+                     else
+                        shift += 2;
+
+                     dp--;
+                  }
+                  break;
+               }
+               case 4:
+               {
+                  gray = (png_uint_16)(gray*0x11);
+                  sp = row + (png_size_t)((row_width - 1) >> 1);
+                  dp = row + (png_size_t)row_width - 1;
+                  shift = (int)((1 - ((row_width + 1) & 0x01)) << 2);
+                  for (i = 0; i < row_width; i++)
+                  {
+                     value = (*sp >> shift) & 0x0f;
+                     *dp = (png_byte)(value | (value << 4));
+                     if (shift == 4)
+                     {
+                        shift = 0;
+                        sp--;
+                     }
+                     else
+                        shift = 4;
+
+                     dp--;
+                  }
+                  break;
+               }
+            }
+            row_info->bit_depth = 8;
+            row_info->pixel_depth = 8;
+            row_info->rowbytes = row_width;
+         }
+
+         if (trans_value != NULL)
+         {
+            if (row_info->bit_depth == 8)
+            {
+               sp = row + (png_size_t)row_width - 1;
+               dp = row + (png_size_t)(row_width << 1) - 1;
+               for (i = 0; i < row_width; i++)
+               {
+                  if (*sp == gray)
+                     *dp-- = 0;
+                  else
+                     *dp-- = 0xff;
+                  *dp-- = *sp--;
+               }
+            }
+            else if (row_info->bit_depth == 16)
+            {
+               sp = row + row_info->rowbytes - 1;
+               dp = row + (row_info->rowbytes << 1) - 1;
+               for (i = 0; i < row_width; i++)
+               {
+                  if (((png_uint_16)*(sp) |
+                     ((png_uint_16)*(sp - 1) << 8)) == gray)
+                  {
+                     *dp-- = 0;
+                     *dp-- = 0;
+                  }
+                  else
+                  {
+                     *dp-- = 0xff;
+                     *dp-- = 0xff;
+                  }
+                  *dp-- = *sp--;
+                  *dp-- = *sp--;
+               }
+            }
+            row_info->color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
+            row_info->channels = 2;
+            row_info->pixel_depth = (png_byte)(row_info->bit_depth << 1);
+            row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,
+               row_width);
+         }
+      }
+      else if (row_info->color_type == PNG_COLOR_TYPE_RGB && trans_value)
+      {
+         if (row_info->bit_depth == 8)
+         {
+            sp = row + (png_size_t)row_info->rowbytes - 1;
+            dp = row + (png_size_t)(row_width << 2) - 1;
+            for (i = 0; i < row_width; i++)
+            {
+               if (*(sp - 2) == trans_value->red &&
+                  *(sp - 1) == trans_value->green &&
+                  *(sp - 0) == trans_value->blue)
+                  *dp-- = 0;
+               else
+                  *dp-- = 0xff;
+               *dp-- = *sp--;
+               *dp-- = *sp--;
+               *dp-- = *sp--;
+            }
+         }
+         else if (row_info->bit_depth == 16)
+         {
+            sp = row + row_info->rowbytes - 1;
+            dp = row + (png_size_t)(row_width << 3) - 1;
+            for (i = 0; i < row_width; i++)
+            {
+               if ((((png_uint_16)*(sp - 4) |
+                  ((png_uint_16)*(sp - 5) << 8)) == trans_value->red) &&
+                  (((png_uint_16)*(sp - 2) |
+                  ((png_uint_16)*(sp - 3) << 8)) == trans_value->green) &&
+                  (((png_uint_16)*(sp - 0) |
+                  ((png_uint_16)*(sp - 1) << 8)) == trans_value->blue))
+               {
+                  *dp-- = 0;
+                  *dp-- = 0;
+               }
+               else
+               {
+                  *dp-- = 0xff;
+                  *dp-- = 0xff;
+               }
+               *dp-- = *sp--;
+               *dp-- = *sp--;
+               *dp-- = *sp--;
+               *dp-- = *sp--;
+               *dp-- = *sp--;
+               *dp-- = *sp--;
+            }
+         }
+         row_info->color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+         row_info->channels = 4;
+         row_info->pixel_depth = (png_byte)(row_info->bit_depth << 2);
+         row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+      }
+   }
+}
+#endif
+
+#if defined(PNG_READ_DITHER_SUPPORTED)
+void /* PRIVATE */
+png_do_dither(png_row_infop row_info, png_bytep row,
+    png_bytep palette_lookup, png_bytep dither_lookup)
+{
+   png_bytep sp, dp;
+   png_uint_32 i;
+   png_uint_32 row_width=row_info->width;
+
+   png_debug(1, "in png_do_dither\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL)
+#endif
+   {
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB &&
+         palette_lookup && row_info->bit_depth == 8)
+      {
+         int r, g, b, p;
+         sp = row;
+         dp = row;
+         for (i = 0; i < row_width; i++)
+         {
+            r = *sp++;
+            g = *sp++;
+            b = *sp++;
+
+            /* this looks real messy, but the compiler will reduce
+               it down to a reasonable formula.  For example, with
+               5 bits per color, we get:
+               p = (((r >> 3) & 0x1f) << 10) |
+                  (((g >> 3) & 0x1f) << 5) |
+                  ((b >> 3) & 0x1f);
+               */
+            p = (((r >> (8 - PNG_DITHER_RED_BITS)) &
+               ((1 << PNG_DITHER_RED_BITS) - 1)) <<
+               (PNG_DITHER_GREEN_BITS + PNG_DITHER_BLUE_BITS)) |
+               (((g >> (8 - PNG_DITHER_GREEN_BITS)) &
+               ((1 << PNG_DITHER_GREEN_BITS) - 1)) <<
+               (PNG_DITHER_BLUE_BITS)) |
+               ((b >> (8 - PNG_DITHER_BLUE_BITS)) &
+               ((1 << PNG_DITHER_BLUE_BITS) - 1));
+
+            *dp++ = palette_lookup[p];
+         }
+         row_info->color_type = PNG_COLOR_TYPE_PALETTE;
+         row_info->channels = 1;
+         row_info->pixel_depth = row_info->bit_depth;
+         row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+      }
+      else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA &&
+         palette_lookup != NULL && row_info->bit_depth == 8)
+      {
+         int r, g, b, p;
+         sp = row;
+         dp = row;
+         for (i = 0; i < row_width; i++)
+         {
+            r = *sp++;
+            g = *sp++;
+            b = *sp++;
+            sp++;
+
+            p = (((r >> (8 - PNG_DITHER_RED_BITS)) &
+               ((1 << PNG_DITHER_RED_BITS) - 1)) <<
+               (PNG_DITHER_GREEN_BITS + PNG_DITHER_BLUE_BITS)) |
+               (((g >> (8 - PNG_DITHER_GREEN_BITS)) &
+               ((1 << PNG_DITHER_GREEN_BITS) - 1)) <<
+               (PNG_DITHER_BLUE_BITS)) |
+               ((b >> (8 - PNG_DITHER_BLUE_BITS)) &
+               ((1 << PNG_DITHER_BLUE_BITS) - 1));
+
+            *dp++ = palette_lookup[p];
+         }
+         row_info->color_type = PNG_COLOR_TYPE_PALETTE;
+         row_info->channels = 1;
+         row_info->pixel_depth = row_info->bit_depth;
+         row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,row_width);
+      }
+      else if (row_info->color_type == PNG_COLOR_TYPE_PALETTE &&
+         dither_lookup && row_info->bit_depth == 8)
+      {
+         sp = row;
+         for (i = 0; i < row_width; i++, sp++)
+         {
+            *sp = dither_lookup[*sp];
+         }
+      }
+   }
+}
+#endif
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+static int png_gamma_shift[] =
+   {0x10, 0x21, 0x42, 0x84, 0x110, 0x248, 0x550, 0xff0};
+
+/* We build the 8- or 16-bit gamma tables here.  Note that for 16-bit
+ * tables, we don't make a full table if we are reducing to 8-bit in
+ * the future.  Note also how the gamma_16 tables are segmented so that
+ * we don't need to allocate > 64K chunks for a full 16-bit table.
+ */
+void /* PRIVATE */
+png_build_gamma_table(png_structp png_ptr)
+{
+  png_debug(1, "in png_build_gamma_table\n");
+  if(png_ptr->gamma != 0.0)
+  {
+   if (png_ptr->bit_depth <= 8)
+   {
+      int i;
+      double g;
+
+      if (png_ptr->screen_gamma > .000001)
+         g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma);
+      else
+         g = 1.0;
+
+      png_ptr->gamma_table = (png_bytep)png_malloc(png_ptr,
+         (png_uint_32)256);
+
+      for (i = 0; i < 256; i++)
+      {
+         png_ptr->gamma_table[i] = (png_byte)(pow((double)i / 255.0,
+            g) * 255.0 + .5);
+      }
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
+    defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+      if (png_ptr->transformations & ((PNG_BACKGROUND) | PNG_RGB_TO_GRAY))
+      {
+
+         g = 1.0 / (png_ptr->gamma);
+
+         png_ptr->gamma_to_1 = (png_bytep)png_malloc(png_ptr,
+            (png_uint_32)256);
+
+         for (i = 0; i < 256; i++)
+         {
+            png_ptr->gamma_to_1[i] = (png_byte)(pow((double)i / 255.0,
+               g) * 255.0 + .5);
+         }
+
+
+         png_ptr->gamma_from_1 = (png_bytep)png_malloc(png_ptr,
+            (png_uint_32)256);
+
+         if(png_ptr->screen_gamma > 0.000001)
+            g = 1.0 / png_ptr->screen_gamma;
+         else
+            g = png_ptr->gamma;   /* probably doing rgb_to_gray */
+
+         for (i = 0; i < 256; i++)
+         {
+            png_ptr->gamma_from_1[i] = (png_byte)(pow((double)i / 255.0,
+               g) * 255.0 + .5);
+
+         }
+      }
+#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */
+   }
+   else
+   {
+      double g;
+      int i, j, shift, num;
+      int sig_bit;
+      png_uint_32 ig;
+
+      if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
+      {
+         sig_bit = (int)png_ptr->sig_bit.red;
+         if ((int)png_ptr->sig_bit.green > sig_bit)
+            sig_bit = png_ptr->sig_bit.green;
+         if ((int)png_ptr->sig_bit.blue > sig_bit)
+            sig_bit = png_ptr->sig_bit.blue;
+      }
+      else
+      {
+         sig_bit = (int)png_ptr->sig_bit.gray;
+      }
+
+      if (sig_bit > 0)
+         shift = 16 - sig_bit;
+      else
+         shift = 0;
+
+      if (png_ptr->transformations & PNG_16_TO_8)
+      {
+         if (shift < (16 - PNG_MAX_GAMMA_8))
+            shift = (16 - PNG_MAX_GAMMA_8);
+      }
+
+      if (shift > 8)
+         shift = 8;
+      if (shift < 0)
+         shift = 0;
+
+      png_ptr->gamma_shift = (png_byte)shift;
+
+      num = (1 << (8 - shift));
+
+      if (png_ptr->screen_gamma > .000001)
+         g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma);
+      else
+         g = 1.0;
+
+      png_ptr->gamma_16_table = (png_uint_16pp)png_malloc(png_ptr,
+         (png_uint_32)(num * png_sizeof (png_uint_16p)));
+
+      if (png_ptr->transformations & (PNG_16_TO_8 | PNG_BACKGROUND))
+      {
+         double fin, fout;
+         png_uint_32 last, max;
+
+         for (i = 0; i < num; i++)
+         {
+            png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
+               (png_uint_32)(256 * png_sizeof (png_uint_16)));
+         }
+
+         g = 1.0 / g;
+         last = 0;
+         for (i = 0; i < 256; i++)
+         {
+            fout = ((double)i + 0.5) / 256.0;
+            fin = pow(fout, g);
+            max = (png_uint_32)(fin * (double)((png_uint_32)num << 8));
+            while (last <= max)
+            {
+               png_ptr->gamma_16_table[(int)(last & (0xff >> shift))]
+                  [(int)(last >> (8 - shift))] = (png_uint_16)(
+                  (png_uint_16)i | ((png_uint_16)i << 8));
+               last++;
+            }
+         }
+         while (last < ((png_uint_32)num << 8))
+         {
+            png_ptr->gamma_16_table[(int)(last & (0xff >> shift))]
+               [(int)(last >> (8 - shift))] = (png_uint_16)65535L;
+            last++;
+         }
+      }
+      else
+      {
+         for (i = 0; i < num; i++)
+         {
+            png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
+               (png_uint_32)(256 * png_sizeof (png_uint_16)));
+
+            ig = (((png_uint_32)i * (png_uint_32)png_gamma_shift[shift]) >> 4);
+            for (j = 0; j < 256; j++)
+            {
+               png_ptr->gamma_16_table[i][j] =
+                  (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) /
+                     65535.0, g) * 65535.0 + .5);
+            }
+         }
+      }
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
+    defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+      if (png_ptr->transformations & (PNG_BACKGROUND | PNG_RGB_TO_GRAY))
+      {
+
+         g = 1.0 / (png_ptr->gamma);
+
+         png_ptr->gamma_16_to_1 = (png_uint_16pp)png_malloc(png_ptr,
+            (png_uint_32)(num * png_sizeof (png_uint_16p )));
+
+         for (i = 0; i < num; i++)
+         {
+            png_ptr->gamma_16_to_1[i] = (png_uint_16p)png_malloc(png_ptr,
+               (png_uint_32)(256 * png_sizeof (png_uint_16)));
+
+            ig = (((png_uint_32)i *
+               (png_uint_32)png_gamma_shift[shift]) >> 4);
+            for (j = 0; j < 256; j++)
+            {
+               png_ptr->gamma_16_to_1[i][j] =
+                  (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) /
+                     65535.0, g) * 65535.0 + .5);
+            }
+         }
+
+         if(png_ptr->screen_gamma > 0.000001)
+            g = 1.0 / png_ptr->screen_gamma;
+         else
+            g = png_ptr->gamma;   /* probably doing rgb_to_gray */
+
+         png_ptr->gamma_16_from_1 = (png_uint_16pp)png_malloc(png_ptr,
+            (png_uint_32)(num * png_sizeof (png_uint_16p)));
+
+         for (i = 0; i < num; i++)
+         {
+            png_ptr->gamma_16_from_1[i] = (png_uint_16p)png_malloc(png_ptr,
+               (png_uint_32)(256 * png_sizeof (png_uint_16)));
+
+            ig = (((png_uint_32)i *
+               (png_uint_32)png_gamma_shift[shift]) >> 4);
+            for (j = 0; j < 256; j++)
+            {
+               png_ptr->gamma_16_from_1[i][j] =
+                  (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) /
+                     65535.0, g) * 65535.0 + .5);
+            }
+         }
+      }
+#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */
+   }
+ }
+}
+#endif
+/* To do: install integer version of png_build_gamma_table here */
+#endif
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+/* undoes intrapixel differencing  */
+void /* PRIVATE */
+png_do_read_intrapixel(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_read_intrapixel\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+       (row_info->color_type & PNG_COLOR_MASK_COLOR))
+   {
+      int bytes_per_pixel;
+      png_uint_32 row_width = row_info->width;
+      if (row_info->bit_depth == 8)
+      {
+         png_bytep rp;
+         png_uint_32 i;
+
+         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+            bytes_per_pixel = 3;
+         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+            bytes_per_pixel = 4;
+         else
+            return;
+
+         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+         {
+            *(rp) = (png_byte)((256 + *rp + *(rp+1))&0xff);
+            *(rp+2) = (png_byte)((256 + *(rp+2) + *(rp+1))&0xff);
+         }
+      }
+      else if (row_info->bit_depth == 16)
+      {
+         png_bytep rp;
+         png_uint_32 i;
+
+         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+            bytes_per_pixel = 6;
+         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+            bytes_per_pixel = 8;
+         else
+            return;
+
+         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+         {
+            png_uint_32 s0   = (*(rp  ) << 8) | *(rp+1);
+            png_uint_32 s1   = (*(rp+2) << 8) | *(rp+3);
+            png_uint_32 s2   = (*(rp+4) << 8) | *(rp+5);
+            png_uint_32 red  = (png_uint_32)((s0+s1+65536L) & 0xffffL);
+            png_uint_32 blue = (png_uint_32)((s2+s1+65536L) & 0xffffL);
+            *(rp  ) = (png_byte)((red >> 8) & 0xff);
+            *(rp+1) = (png_byte)(red & 0xff);
+            *(rp+4) = (png_byte)((blue >> 8) & 0xff);
+            *(rp+5) = (png_byte)(blue & 0xff);
+         }
+      }
+   }
+}
+#endif /* PNG_MNG_FEATURES_SUPPORTED */
diff --git a/gs/libpng/pngrutil.c b/gs/libpng/pngrutil.c
new file mode 100644
index 000000000..99e466f18
--- /dev/null
+++ b/gs/libpng/pngrutil.c
@@ -0,0 +1,3124 @@
+/* pngrutil.c - utilities to read a PNG file
+ *
+ * libpng version 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file contains routines that are only called from within
+ * libpng itself during the course of reading an image.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(_WIN32_WCE)
+/* strtod() function is not supported on WindowsCE */
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
+__inline double strtod(const char *nptr, char **endptr)
+{
+   double result = 0;
+   int len;
+   wchar_t *str, *end;
+
+   len = MultiByteToWideChar(CP_ACP, 0, nptr, -1, NULL, 0);
+   str = (wchar_t *)malloc(len * sizeof(wchar_t));
+   if ( NULL != str )
+   {
+      MultiByteToWideChar(CP_ACP, 0, nptr, -1, str, len);
+      result = wcstod(str, &end);
+      len = WideCharToMultiByte(CP_ACP, 0, end, -1, NULL, 0, NULL, NULL);
+      *endptr = (char *)nptr + (png_strlen(nptr) - len + 1);
+      free(str);
+   }
+   return result;
+}
+#  endif
+#endif
+
+png_uint_32 /* PRIVATE */
+png_get_uint_31(png_structp png_ptr, png_bytep buf)
+{
+   png_uint_32 i = png_get_uint_32(buf);
+   if (i > PNG_UINT_31_MAX)
+     png_error(png_ptr, "PNG unsigned integer out of range.\n");
+   return (i);
+}
+#ifndef PNG_READ_BIG_ENDIAN_SUPPORTED
+/* Grab an unsigned 32-bit integer from a buffer in big-endian format. */
+png_uint_32 /* PRIVATE */
+png_get_uint_32(png_bytep buf)
+{
+   png_uint_32 i = ((png_uint_32)(*buf) << 24) +
+      ((png_uint_32)(*(buf + 1)) << 16) +
+      ((png_uint_32)(*(buf + 2)) << 8) +
+      (png_uint_32)(*(buf + 3));
+
+   return (i);
+}
+
+#if defined(PNG_READ_pCAL_SUPPORTED) || defined(PNG_READ_oFFs_SUPPORTED)
+/* Grab a signed 32-bit integer from a buffer in big-endian format.  The
+ * data is stored in the PNG file in two's complement format, and it is
+ * assumed that the machine format for signed integers is the same. */
+png_int_32 /* PRIVATE */
+png_get_int_32(png_bytep buf)
+{
+   png_int_32 i = ((png_int_32)(*buf) << 24) +
+      ((png_int_32)(*(buf + 1)) << 16) +
+      ((png_int_32)(*(buf + 2)) << 8) +
+      (png_int_32)(*(buf + 3));
+
+   return (i);
+}
+#endif /* PNG_READ_pCAL_SUPPORTED */
+
+/* Grab an unsigned 16-bit integer from a buffer in big-endian format. */
+png_uint_16 /* PRIVATE */
+png_get_uint_16(png_bytep buf)
+{
+   png_uint_16 i = (png_uint_16)(((png_uint_16)(*buf) << 8) +
+      (png_uint_16)(*(buf + 1)));
+
+   return (i);
+}
+#endif /* PNG_READ_BIG_ENDIAN_SUPPORTED */
+
+/* Read data, and (optionally) run it through the CRC. */
+void /* PRIVATE */
+png_crc_read(png_structp png_ptr, png_bytep buf, png_size_t length)
+{
+   png_read_data(png_ptr, buf, length);
+   png_calculate_crc(png_ptr, buf, length);
+}
+
+/* Optionally skip data and then check the CRC.  Depending on whether we
+   are reading a ancillary or critical chunk, and how the program has set
+   things up, we may calculate the CRC on the data and print a message.
+   Returns '1' if there was a CRC error, '0' otherwise. */
+int /* PRIVATE */
+png_crc_finish(png_structp png_ptr, png_uint_32 skip)
+{
+   png_size_t i;
+   png_size_t istop = png_ptr->zbuf_size;
+
+   for (i = (png_size_t)skip; i > istop; i -= istop)
+   {
+      png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
+   }
+   if (i)
+   {
+      png_crc_read(png_ptr, png_ptr->zbuf, i);
+   }
+
+   if (png_crc_error(png_ptr))
+   {
+      if (((png_ptr->chunk_name[0] & 0x20) &&                /* Ancillary */
+           !(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)) ||
+          (!(png_ptr->chunk_name[0] & 0x20) &&             /* Critical  */
+          (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE)))
+      {
+         png_chunk_warning(png_ptr, "CRC error");
+      }
+      else
+      {
+         png_chunk_error(png_ptr, "CRC error");
+      }
+      return (1);
+   }
+
+   return (0);
+}
+
+/* Compare the CRC stored in the PNG file with that calculated by libpng from
+   the data it has read thus far. */
+int /* PRIVATE */
+png_crc_error(png_structp png_ptr)
+{
+   png_byte crc_bytes[4];
+   png_uint_32 crc;
+   int need_crc = 1;
+
+   if (png_ptr->chunk_name[0] & 0x20)                     /* ancillary */
+   {
+      if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
+          (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
+         need_crc = 0;
+   }
+   else                                                    /* critical */
+   {
+      if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE)
+         need_crc = 0;
+   }
+
+   png_read_data(png_ptr, crc_bytes, 4);
+
+   if (need_crc)
+   {
+      crc = png_get_uint_32(crc_bytes);
+      return ((int)(crc != png_ptr->crc));
+   }
+   else
+      return (0);
+}
+
+#if defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_READ_iTXt_SUPPORTED) || \
+    defined(PNG_READ_iCCP_SUPPORTED)
+/*
+ * Decompress trailing data in a chunk.  The assumption is that chunkdata
+ * points at an allocated area holding the contents of a chunk with a
+ * trailing compressed part.  What we get back is an allocated area
+ * holding the original prefix part and an uncompressed version of the
+ * trailing part (the malloc area passed in is freed).
+ */
+png_charp /* PRIVATE */
+png_decompress_chunk(png_structp png_ptr, int comp_type,
+                              png_charp chunkdata, png_size_t chunklength,
+                              png_size_t prefix_size, png_size_t *newlength)
+{
+   static char msg[] = "Error decoding compressed text";
+   png_charp text;
+   png_size_t text_size;
+
+   if (comp_type == PNG_COMPRESSION_TYPE_BASE)
+   {
+      int ret = Z_OK;
+      png_ptr->zstream.next_in = (png_bytep)(chunkdata + prefix_size);
+      png_ptr->zstream.avail_in = (uInt)(chunklength - prefix_size);
+      png_ptr->zstream.next_out = png_ptr->zbuf;
+      png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+
+      text_size = 0;
+      text = NULL;
+
+      while (png_ptr->zstream.avail_in)
+      {
+         ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+         if (ret != Z_OK && ret != Z_STREAM_END)
+         {
+            if (png_ptr->zstream.msg != NULL)
+               png_warning(png_ptr, png_ptr->zstream.msg);
+            else
+               png_warning(png_ptr, msg);
+            inflateReset(&png_ptr->zstream);
+            png_ptr->zstream.avail_in = 0;
+
+            if (text ==  NULL)
+            {
+               text_size = prefix_size + png_sizeof(msg) + 1;
+               text = (png_charp)png_malloc_warn(png_ptr, text_size);
+               if (text ==  NULL)
+                 {
+                    png_free(png_ptr,chunkdata);
+                    png_error(png_ptr,"Not enough memory to decompress chunk");
+                 }
+               png_memcpy(text, chunkdata, prefix_size);
+            }
+
+            text[text_size - 1] = 0x00;
+
+            /* Copy what we can of the error message into the text chunk */
+            text_size = (png_size_t)(chunklength - (text - chunkdata) - 1);
+            text_size = png_sizeof(msg) > text_size ? text_size :
+               png_sizeof(msg);
+            png_memcpy(text + prefix_size, msg, text_size + 1);
+            break;
+         }
+         if (!png_ptr->zstream.avail_out || ret == Z_STREAM_END)
+         {
+            if (text == NULL)
+            {
+               text_size = prefix_size +
+                   png_ptr->zbuf_size - png_ptr->zstream.avail_out;
+               text = (png_charp)png_malloc_warn(png_ptr, text_size + 1);
+               if (text ==  NULL)
+                 {
+                    png_free(png_ptr,chunkdata);
+                    png_error(png_ptr,"Not enough memory to decompress chunk.");
+                 }
+               png_memcpy(text + prefix_size, png_ptr->zbuf,
+                    text_size - prefix_size);
+               png_memcpy(text, chunkdata, prefix_size);
+               *(text + text_size) = 0x00;
+            }
+            else
+            {
+               png_charp tmp;
+
+               tmp = text;
+               text = (png_charp)png_malloc_warn(png_ptr,
+                  (png_uint_32)(text_size +
+                  png_ptr->zbuf_size - png_ptr->zstream.avail_out + 1));
+               if (text == NULL)
+               {
+                  png_free(png_ptr, tmp);
+                  png_free(png_ptr, chunkdata);
+                  png_error(png_ptr,"Not enough memory to decompress chunk..");
+               }
+               png_memcpy(text, tmp, text_size);
+               png_free(png_ptr, tmp);
+               png_memcpy(text + text_size, png_ptr->zbuf,
+                  (png_ptr->zbuf_size - png_ptr->zstream.avail_out));
+               text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;
+               *(text + text_size) = 0x00;
+            }
+            if (ret == Z_STREAM_END)
+               break;
+            else
+            {
+               png_ptr->zstream.next_out = png_ptr->zbuf;
+               png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+            }
+         }
+      }
+      if (ret != Z_STREAM_END)
+      {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+         char umsg[50];
+
+         if (ret == Z_BUF_ERROR)
+            sprintf(umsg,"Buffer error in compressed datastream in %s chunk",
+                png_ptr->chunk_name);
+         else if (ret == Z_DATA_ERROR)
+            sprintf(umsg,"Data error in compressed datastream in %s chunk",
+                png_ptr->chunk_name);
+         else
+            sprintf(umsg,"Incomplete compressed datastream in %s chunk",
+                png_ptr->chunk_name);
+         png_warning(png_ptr, umsg);
+#else
+         png_warning(png_ptr,
+            "Incomplete compressed datastream in chunk other than IDAT");
+#endif
+         text_size=prefix_size;
+         if (text ==  NULL)
+         {
+            text = (png_charp)png_malloc_warn(png_ptr, text_size+1);
+            if (text == NULL)
+              {
+                png_free(png_ptr, chunkdata);
+                png_error(png_ptr,"Not enough memory for text.");
+              }
+            png_memcpy(text, chunkdata, prefix_size);
+         }
+         *(text + text_size) = 0x00;
+      }
+
+      inflateReset(&png_ptr->zstream);
+      png_ptr->zstream.avail_in = 0;
+
+      png_free(png_ptr, chunkdata);
+      chunkdata = text;
+      *newlength=text_size;
+   }
+   else /* if (comp_type != PNG_COMPRESSION_TYPE_BASE) */
+   {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+      char umsg[50];
+
+      sprintf(umsg, "Unknown zTXt compression type %d", comp_type);
+      png_warning(png_ptr, umsg);
+#else
+      png_warning(png_ptr, "Unknown zTXt compression type");
+#endif
+
+      *(chunkdata + prefix_size) = 0x00;
+      *newlength=prefix_size;
+   }
+
+   return chunkdata;
+}
+#endif
+
+/* read and check the IDHR chunk */
+void /* PRIVATE */
+png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_byte buf[13];
+   png_uint_32 width, height;
+   int bit_depth, color_type, compression_type, filter_type;
+   int interlace_type;
+
+   png_debug(1, "in png_handle_IHDR\n");
+
+   if (png_ptr->mode & PNG_HAVE_IHDR)
+      png_error(png_ptr, "Out of place IHDR");
+
+   /* check the length */
+   if (length != 13)
+      png_error(png_ptr, "Invalid IHDR chunk");
+
+   png_ptr->mode |= PNG_HAVE_IHDR;
+
+   png_crc_read(png_ptr, buf, 13);
+   png_crc_finish(png_ptr, 0);
+
+   width = png_get_uint_31(png_ptr, buf);
+   height = png_get_uint_31(png_ptr, buf + 4);
+   bit_depth = buf[8];
+   color_type = buf[9];
+   compression_type = buf[10];
+   filter_type = buf[11];
+   interlace_type = buf[12];
+
+   /* set internal variables */
+   png_ptr->width = width;
+   png_ptr->height = height;
+   png_ptr->bit_depth = (png_byte)bit_depth;
+   png_ptr->interlaced = (png_byte)interlace_type;
+   png_ptr->color_type = (png_byte)color_type;
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+   png_ptr->filter_type = (png_byte)filter_type;
+#endif
+   png_ptr->compression_type = (png_byte)compression_type;
+
+   /* find number of channels */
+   switch (png_ptr->color_type)
+   {
+      case PNG_COLOR_TYPE_GRAY:
+      case PNG_COLOR_TYPE_PALETTE:
+         png_ptr->channels = 1;
+         break;
+      case PNG_COLOR_TYPE_RGB:
+         png_ptr->channels = 3;
+         break;
+      case PNG_COLOR_TYPE_GRAY_ALPHA:
+         png_ptr->channels = 2;
+         break;
+      case PNG_COLOR_TYPE_RGB_ALPHA:
+         png_ptr->channels = 4;
+         break;
+   }
+
+   /* set up other useful info */
+   png_ptr->pixel_depth = (png_byte)(png_ptr->bit_depth *
+   png_ptr->channels);
+   png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth,png_ptr->width);
+   png_debug1(3,"bit_depth = %d\n", png_ptr->bit_depth);
+   png_debug1(3,"channels = %d\n", png_ptr->channels);
+   png_debug1(3,"rowbytes = %lu\n", png_ptr->rowbytes);
+   png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth,
+      color_type, interlace_type, compression_type, filter_type);
+}
+
+/* read and check the palette */
+void /* PRIVATE */
+png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_color palette[PNG_MAX_PALETTE_LENGTH];
+   int num, i;
+#ifndef PNG_NO_POINTER_INDEXING
+   png_colorp pal_ptr;
+#endif
+
+   png_debug(1, "in png_handle_PLTE\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before PLTE");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid PLTE after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (png_ptr->mode & PNG_HAVE_PLTE)
+      png_error(png_ptr, "Duplicate PLTE chunk");
+
+   png_ptr->mode |= PNG_HAVE_PLTE;
+
+   if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR))
+   {
+      png_warning(png_ptr,
+        "Ignoring PLTE chunk in grayscale PNG");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
+   if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
+   {
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+#endif
+
+   if (length > 3*PNG_MAX_PALETTE_LENGTH || length % 3)
+   {
+      if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
+      {
+         png_warning(png_ptr, "Invalid palette chunk");
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+      else
+      {
+         png_error(png_ptr, "Invalid palette chunk");
+      }
+   }
+
+   num = (int)length / 3;
+
+#ifndef PNG_NO_POINTER_INDEXING
+   for (i = 0, pal_ptr = palette; i < num; i++, pal_ptr++)
+   {
+      png_byte buf[3];
+
+      png_crc_read(png_ptr, buf, 3);
+      pal_ptr->red = buf[0];
+      pal_ptr->green = buf[1];
+      pal_ptr->blue = buf[2];
+   }
+#else
+   for (i = 0; i < num; i++)
+   {
+      png_byte buf[3];
+
+      png_crc_read(png_ptr, buf, 3);
+      /* don't depend upon png_color being any order */
+      palette[i].red = buf[0];
+      palette[i].green = buf[1];
+      palette[i].blue = buf[2];
+   }
+#endif
+
+   /* If we actually NEED the PLTE chunk (ie for a paletted image), we do
+      whatever the normal CRC configuration tells us.  However, if we
+      have an RGB image, the PLTE can be considered ancillary, so
+      we will act as though it is. */
+#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
+   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+#endif
+   {
+      png_crc_finish(png_ptr, 0);
+   }
+#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
+   else if (png_crc_error(png_ptr))  /* Only if we have a CRC error */
+   {
+      /* If we don't want to use the data from an ancillary chunk,
+         we have two options: an error abort, or a warning and we
+         ignore the data in this chunk (which should be OK, since
+         it's considered ancillary for a RGB or RGBA image). */
+      if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_USE))
+      {
+         if (png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)
+         {
+            png_chunk_error(png_ptr, "CRC error");
+         }
+         else
+         {
+            png_chunk_warning(png_ptr, "CRC error");
+            return;
+         }
+      }
+      /* Otherwise, we (optionally) emit a warning and use the chunk. */
+      else if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN))
+      {
+         png_chunk_warning(png_ptr, "CRC error");
+      }
+   }
+#endif
+
+   png_set_PLTE(png_ptr, info_ptr, palette, num);
+
+#if defined(PNG_READ_tRNS_SUPPORTED)
+   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+   {
+      if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
+      {
+         if (png_ptr->num_trans > (png_uint_16)num)
+         {
+            png_warning(png_ptr, "Truncating incorrect tRNS chunk length");
+            png_ptr->num_trans = (png_uint_16)num;
+         }
+         if (info_ptr->num_trans > (png_uint_16)num)
+         {
+            png_warning(png_ptr, "Truncating incorrect info tRNS chunk length");
+            info_ptr->num_trans = (png_uint_16)num;
+         }
+      }
+   }
+#endif
+
+}
+
+void /* PRIVATE */
+png_handle_IEND(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_debug(1, "in png_handle_IEND\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR) || !(png_ptr->mode & PNG_HAVE_IDAT))
+   {
+      png_error(png_ptr, "No image in file");
+   }
+
+   png_ptr->mode |= (PNG_AFTER_IDAT | PNG_HAVE_IEND);
+
+   if (length != 0)
+   {
+      png_warning(png_ptr, "Incorrect IEND chunk length");
+   }
+   png_crc_finish(png_ptr, length);
+
+   if (&info_ptr == NULL) /* quiet compiler warnings about unused info_ptr */
+      return;
+}
+
+#if defined(PNG_READ_gAMA_SUPPORTED)
+void /* PRIVATE */
+png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_fixed_point igamma;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   float file_gamma;
+#endif
+   png_byte buf[4];
+
+   png_debug(1, "in png_handle_gAMA\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before gAMA");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid gAMA after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (png_ptr->mode & PNG_HAVE_PLTE)
+      /* Should be an error, but we can cope with it */
+      png_warning(png_ptr, "Out of place gAMA chunk");
+
+   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
+#if defined(PNG_READ_sRGB_SUPPORTED)
+      && !(info_ptr->valid & PNG_INFO_sRGB)
+#endif
+      )
+   {
+      png_warning(png_ptr, "Duplicate gAMA chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   if (length != 4)
+   {
+      png_warning(png_ptr, "Incorrect gAMA chunk length");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   png_crc_read(png_ptr, buf, 4);
+   if (png_crc_finish(png_ptr, 0))
+      return;
+
+   igamma = (png_fixed_point)png_get_uint_32(buf);
+   /* check for zero gamma */
+   if (igamma == 0)
+      {
+         png_warning(png_ptr,
+           "Ignoring gAMA chunk with gamma=0");
+         return;
+      }
+
+#if defined(PNG_READ_sRGB_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_sRGB)
+      if (PNG_OUT_OF_RANGE(igamma, 45500L, 500))
+      {
+         png_warning(png_ptr,
+           "Ignoring incorrect gAMA value when sRGB is also present");
+#ifndef PNG_NO_CONSOLE_IO
+         fprintf(stderr, "gamma = (%d/100000)\n", (int)igamma);
+#endif
+         return;
+      }
+#endif /* PNG_READ_sRGB_SUPPORTED */
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   file_gamma = (float)igamma / (float)100000.0;
+#  ifdef PNG_READ_GAMMA_SUPPORTED
+     png_ptr->gamma = file_gamma;
+#  endif
+     png_set_gAMA(png_ptr, info_ptr, file_gamma);
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   png_set_gAMA_fixed(png_ptr, info_ptr, igamma);
+#endif
+}
+#endif
+
+#if defined(PNG_READ_sBIT_SUPPORTED)
+void /* PRIVATE */
+png_handle_sBIT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_size_t truelen;
+   png_byte buf[4];
+
+   png_debug(1, "in png_handle_sBIT\n");
+
+   buf[0] = buf[1] = buf[2] = buf[3] = 0;
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before sBIT");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid sBIT after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (png_ptr->mode & PNG_HAVE_PLTE)
+   {
+      /* Should be an error, but we can cope with it */
+      png_warning(png_ptr, "Out of place sBIT chunk");
+   }
+   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT))
+   {
+      png_warning(png_ptr, "Duplicate sBIT chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      truelen = 3;
+   else
+      truelen = (png_size_t)png_ptr->channels;
+
+   if (length != truelen || length > 4)
+   {
+      png_warning(png_ptr, "Incorrect sBIT chunk length");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   png_crc_read(png_ptr, buf, truelen);
+   if (png_crc_finish(png_ptr, 0))
+      return;
+
+   if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
+   {
+      png_ptr->sig_bit.red = buf[0];
+      png_ptr->sig_bit.green = buf[1];
+      png_ptr->sig_bit.blue = buf[2];
+      png_ptr->sig_bit.alpha = buf[3];
+   }
+   else
+   {
+      png_ptr->sig_bit.gray = buf[0];
+      png_ptr->sig_bit.red = buf[0];
+      png_ptr->sig_bit.green = buf[0];
+      png_ptr->sig_bit.blue = buf[0];
+      png_ptr->sig_bit.alpha = buf[1];
+   }
+   png_set_sBIT(png_ptr, info_ptr, &(png_ptr->sig_bit));
+}
+#endif
+
+#if defined(PNG_READ_cHRM_SUPPORTED)
+void /* PRIVATE */
+png_handle_cHRM(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_byte buf[4];
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
+#endif
+   png_fixed_point int_x_white, int_y_white, int_x_red, int_y_red, int_x_green,
+      int_y_green, int_x_blue, int_y_blue;
+
+   png_uint_32 uint_x, uint_y;
+
+   png_debug(1, "in png_handle_cHRM\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before cHRM");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid cHRM after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (png_ptr->mode & PNG_HAVE_PLTE)
+      /* Should be an error, but we can cope with it */
+      png_warning(png_ptr, "Missing PLTE before cHRM");
+
+   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM)
+#if defined(PNG_READ_sRGB_SUPPORTED)
+      && !(info_ptr->valid & PNG_INFO_sRGB)
+#endif
+      )
+   {
+      png_warning(png_ptr, "Duplicate cHRM chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   if (length != 32)
+   {
+      png_warning(png_ptr, "Incorrect cHRM chunk length");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   png_crc_read(png_ptr, buf, 4);
+   uint_x = png_get_uint_32(buf);
+
+   png_crc_read(png_ptr, buf, 4);
+   uint_y = png_get_uint_32(buf);
+
+   if (uint_x > 80000L || uint_y > 80000L ||
+      uint_x + uint_y > 100000L)
+   {
+      png_warning(png_ptr, "Invalid cHRM white point");
+      png_crc_finish(png_ptr, 24);
+      return;
+   }
+   int_x_white = (png_fixed_point)uint_x;
+   int_y_white = (png_fixed_point)uint_y;
+
+   png_crc_read(png_ptr, buf, 4);
+   uint_x = png_get_uint_32(buf);
+
+   png_crc_read(png_ptr, buf, 4);
+   uint_y = png_get_uint_32(buf);
+
+   if (uint_x > 80000L || uint_y > 80000L ||
+      uint_x + uint_y > 100000L)
+   {
+      png_warning(png_ptr, "Invalid cHRM red point");
+      png_crc_finish(png_ptr, 16);
+      return;
+   }
+   int_x_red = (png_fixed_point)uint_x;
+   int_y_red = (png_fixed_point)uint_y;
+
+   png_crc_read(png_ptr, buf, 4);
+   uint_x = png_get_uint_32(buf);
+
+   png_crc_read(png_ptr, buf, 4);
+   uint_y = png_get_uint_32(buf);
+
+   if (uint_x > 80000L || uint_y > 80000L ||
+      uint_x + uint_y > 100000L)
+   {
+      png_warning(png_ptr, "Invalid cHRM green point");
+      png_crc_finish(png_ptr, 8);
+      return;
+   }
+   int_x_green = (png_fixed_point)uint_x;
+   int_y_green = (png_fixed_point)uint_y;
+
+   png_crc_read(png_ptr, buf, 4);
+   uint_x = png_get_uint_32(buf);
+
+   png_crc_read(png_ptr, buf, 4);
+   uint_y = png_get_uint_32(buf);
+
+   if (uint_x > 80000L || uint_y > 80000L ||
+      uint_x + uint_y > 100000L)
+   {
+      png_warning(png_ptr, "Invalid cHRM blue point");
+      png_crc_finish(png_ptr, 0);
+      return;
+   }
+   int_x_blue = (png_fixed_point)uint_x;
+   int_y_blue = (png_fixed_point)uint_y;
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   white_x = (float)int_x_white / (float)100000.0;
+   white_y = (float)int_y_white / (float)100000.0;
+   red_x   = (float)int_x_red   / (float)100000.0;
+   red_y   = (float)int_y_red   / (float)100000.0;
+   green_x = (float)int_x_green / (float)100000.0;
+   green_y = (float)int_y_green / (float)100000.0;
+   blue_x  = (float)int_x_blue  / (float)100000.0;
+   blue_y  = (float)int_y_blue  / (float)100000.0;
+#endif
+
+#if defined(PNG_READ_sRGB_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_sRGB)
+      {
+      if (PNG_OUT_OF_RANGE(int_x_white, 31270,  1000) ||
+          PNG_OUT_OF_RANGE(int_y_white, 32900,  1000) ||
+          PNG_OUT_OF_RANGE(int_x_red,   64000L, 1000) ||
+          PNG_OUT_OF_RANGE(int_y_red,   33000,  1000) ||
+          PNG_OUT_OF_RANGE(int_x_green, 30000,  1000) ||
+          PNG_OUT_OF_RANGE(int_y_green, 60000L, 1000) ||
+          PNG_OUT_OF_RANGE(int_x_blue,  15000,  1000) ||
+          PNG_OUT_OF_RANGE(int_y_blue,   6000,  1000))
+         {
+
+            png_warning(png_ptr,
+              "Ignoring incorrect cHRM value when sRGB is also present");
+#ifndef PNG_NO_CONSOLE_IO
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+            fprintf(stderr,"wx=%f, wy=%f, rx=%f, ry=%f\n",
+               white_x, white_y, red_x, red_y);
+            fprintf(stderr,"gx=%f, gy=%f, bx=%f, by=%f\n",
+               green_x, green_y, blue_x, blue_y);
+#else
+            fprintf(stderr,"wx=%ld, wy=%ld, rx=%ld, ry=%ld\n",
+               int_x_white, int_y_white, int_x_red, int_y_red);
+            fprintf(stderr,"gx=%ld, gy=%ld, bx=%ld, by=%ld\n",
+               int_x_green, int_y_green, int_x_blue, int_y_blue);
+#endif
+#endif /* PNG_NO_CONSOLE_IO */
+         }
+         png_crc_finish(png_ptr, 0);
+         return;
+      }
+#endif /* PNG_READ_sRGB_SUPPORTED */
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   png_set_cHRM(png_ptr, info_ptr,
+      white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   png_set_cHRM_fixed(png_ptr, info_ptr,
+      int_x_white, int_y_white, int_x_red, int_y_red, int_x_green,
+      int_y_green, int_x_blue, int_y_blue);
+#endif
+   if (png_crc_finish(png_ptr, 0))
+      return;
+}
+#endif
+
+#if defined(PNG_READ_sRGB_SUPPORTED)
+void /* PRIVATE */
+png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   int intent;
+   png_byte buf[1];
+
+   png_debug(1, "in png_handle_sRGB\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before sRGB");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid sRGB after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (png_ptr->mode & PNG_HAVE_PLTE)
+      /* Should be an error, but we can cope with it */
+      png_warning(png_ptr, "Out of place sRGB chunk");
+
+   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB))
+   {
+      png_warning(png_ptr, "Duplicate sRGB chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   if (length != 1)
+   {
+      png_warning(png_ptr, "Incorrect sRGB chunk length");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   png_crc_read(png_ptr, buf, 1);
+   if (png_crc_finish(png_ptr, 0))
+      return;
+
+   intent = buf[0];
+   /* check for bad intent */
+   if (intent >= PNG_sRGB_INTENT_LAST)
+   {
+      png_warning(png_ptr, "Unknown sRGB intent");
+      return;
+   }
+
+#if defined(PNG_READ_gAMA_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED)
+   if ((info_ptr->valid & PNG_INFO_gAMA))
+   {
+   png_fixed_point igamma;
+#ifdef PNG_FIXED_POINT_SUPPORTED
+      igamma=info_ptr->int_gamma;
+#else
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
+      igamma=(png_fixed_point)(info_ptr->gamma * 100000.);
+#  endif
+#endif
+      if (PNG_OUT_OF_RANGE(igamma, 45500L, 500))
+      {
+         png_warning(png_ptr,
+           "Ignoring incorrect gAMA value when sRGB is also present");
+#ifndef PNG_NO_CONSOLE_IO
+#  ifdef PNG_FIXED_POINT_SUPPORTED
+         fprintf(stderr,"incorrect gamma=(%d/100000)\n",(int)png_ptr->int_gamma);
+#  else
+#    ifdef PNG_FLOATING_POINT_SUPPORTED
+         fprintf(stderr,"incorrect gamma=%f\n",png_ptr->gamma);
+#    endif
+#  endif
+#endif
+      }
+   }
+#endif /* PNG_READ_gAMA_SUPPORTED */
+
+#ifdef PNG_READ_cHRM_SUPPORTED
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_cHRM)
+      if (PNG_OUT_OF_RANGE(info_ptr->int_x_white, 31270,  1000) ||
+          PNG_OUT_OF_RANGE(info_ptr->int_y_white, 32900,  1000) ||
+          PNG_OUT_OF_RANGE(info_ptr->int_x_red,   64000L, 1000) ||
+          PNG_OUT_OF_RANGE(info_ptr->int_y_red,   33000,  1000) ||
+          PNG_OUT_OF_RANGE(info_ptr->int_x_green, 30000,  1000) ||
+          PNG_OUT_OF_RANGE(info_ptr->int_y_green, 60000L, 1000) ||
+          PNG_OUT_OF_RANGE(info_ptr->int_x_blue,  15000,  1000) ||
+          PNG_OUT_OF_RANGE(info_ptr->int_y_blue,   6000,  1000))
+         {
+            png_warning(png_ptr,
+              "Ignoring incorrect cHRM value when sRGB is also present");
+         }
+#endif /* PNG_FIXED_POINT_SUPPORTED */
+#endif /* PNG_READ_cHRM_SUPPORTED */
+
+   png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr, intent);
+}
+#endif /* PNG_READ_sRGB_SUPPORTED */
+
+#if defined(PNG_READ_iCCP_SUPPORTED)
+void /* PRIVATE */
+png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+/* Note: this does not properly handle chunks that are > 64K under DOS */
+{
+   png_charp chunkdata;
+   png_byte compression_type;
+   png_bytep pC;
+   png_charp profile;
+   png_uint_32 skip = 0;
+   png_uint_32 profile_size, profile_length;
+   png_size_t slength, prefix_length, data_length;
+
+   png_debug(1, "in png_handle_iCCP\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before iCCP");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid iCCP after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (png_ptr->mode & PNG_HAVE_PLTE)
+      /* Should be an error, but we can cope with it */
+      png_warning(png_ptr, "Out of place iCCP chunk");
+
+   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP))
+   {
+      png_warning(png_ptr, "Duplicate iCCP chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+#ifdef PNG_MAX_MALLOC_64K
+   if (length > (png_uint_32)65535L)
+   {
+      png_warning(png_ptr, "iCCP chunk too large to fit in memory");
+      skip = length - (png_uint_32)65535L;
+      length = (png_uint_32)65535L;
+   }
+#endif
+
+   chunkdata = (png_charp)png_malloc(png_ptr, length + 1);
+   slength = (png_size_t)length;
+   png_crc_read(png_ptr, (png_bytep)chunkdata, slength);
+
+   if (png_crc_finish(png_ptr, skip))
+   {
+      png_free(png_ptr, chunkdata);
+      return;
+   }
+
+   chunkdata[slength] = 0x00;
+
+   for (profile = chunkdata; *profile; profile++)
+      /* empty loop to find end of name */ ;
+
+   ++profile;
+
+   /* there should be at least one zero (the compression type byte)
+      following the separator, and we should be on it  */
+   if ( profile >= chunkdata + slength)
+   {
+      png_free(png_ptr, chunkdata);
+      png_warning(png_ptr, "Malformed iCCP chunk");
+      return;
+   }
+
+   /* compression_type should always be zero */
+   compression_type = *profile++;
+   if (compression_type)
+   {
+      png_warning(png_ptr, "Ignoring nonzero compression type in iCCP chunk");
+      compression_type=0x00;  /* Reset it to zero (libpng-1.0.6 through 1.0.8
+                                 wrote nonzero) */
+   }
+
+   prefix_length = profile - chunkdata;
+   chunkdata = png_decompress_chunk(png_ptr, compression_type, chunkdata,
+                                    slength, prefix_length, &data_length);
+
+   profile_length = data_length - prefix_length;
+
+   if ( prefix_length > data_length || profile_length < 4)
+   {
+      png_free(png_ptr, chunkdata);
+      png_warning(png_ptr, "Profile size field missing from iCCP chunk");
+      return;
+   }
+
+   /* Check the profile_size recorded in the first 32 bits of the ICC profile */
+   pC = (png_bytep)(chunkdata+prefix_length);
+   profile_size = ((*(pC  ))<<24) |
+                  ((*(pC+1))<<16) |
+                  ((*(pC+2))<< 8) |
+                  ((*(pC+3))    );
+
+   if(profile_size < profile_length)
+      profile_length = profile_size;
+
+   if(profile_size > profile_length)
+   {
+      png_free(png_ptr, chunkdata);
+      png_warning(png_ptr, "Ignoring truncated iCCP profile.\n");
+      return;
+   }
+
+   png_set_iCCP(png_ptr, info_ptr, chunkdata, compression_type,
+                chunkdata + prefix_length, profile_length);
+   png_free(png_ptr, chunkdata);
+}
+#endif /* PNG_READ_iCCP_SUPPORTED */
+
+#if defined(PNG_READ_sPLT_SUPPORTED)
+void /* PRIVATE */
+png_handle_sPLT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+/* Note: this does not properly handle chunks that are > 64K under DOS */
+{
+   png_bytep chunkdata;
+   png_bytep entry_start;
+   png_sPLT_t new_palette;
+#ifdef PNG_NO_POINTER_INDEXING
+   png_sPLT_entryp pp;
+#endif
+   int data_length, entry_size, i;
+   png_uint_32 skip = 0;
+   png_size_t slength;
+
+   png_debug(1, "in png_handle_sPLT\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before sPLT");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid sPLT after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+#ifdef PNG_MAX_MALLOC_64K
+   if (length > (png_uint_32)65535L)
+   {
+      png_warning(png_ptr, "sPLT chunk too large to fit in memory");
+      skip = length - (png_uint_32)65535L;
+      length = (png_uint_32)65535L;
+   }
+#endif
+
+   chunkdata = (png_bytep)png_malloc(png_ptr, length + 1);
+   slength = (png_size_t)length;
+   png_crc_read(png_ptr, (png_bytep)chunkdata, slength);
+
+   if (png_crc_finish(png_ptr, skip))
+   {
+      png_free(png_ptr, chunkdata);
+      return;
+   }
+
+   chunkdata[slength] = 0x00;
+
+   for (entry_start = chunkdata; *entry_start; entry_start++)
+      /* empty loop to find end of name */ ;
+   ++entry_start;
+
+   /* a sample depth should follow the separator, and we should be on it  */
+   if (entry_start > chunkdata + slength)
+   {
+      png_free(png_ptr, chunkdata);
+      png_warning(png_ptr, "malformed sPLT chunk");
+      return;
+   }
+
+   new_palette.depth = *entry_start++;
+   entry_size = (new_palette.depth == 8 ? 6 : 10);
+   data_length = (slength - (entry_start - chunkdata));
+
+   /* integrity-check the data length */
+   if (data_length % entry_size)
+   {
+      png_free(png_ptr, chunkdata);
+      png_warning(png_ptr, "sPLT chunk has bad length");
+      return;
+   }
+
+   new_palette.nentries = (png_uint_32) (data_length / entry_size);
+   if ((png_uint_32) new_palette.nentries > (png_uint_32) (PNG_SIZE_MAX /
+       png_sizeof(png_sPLT_entry)))
+   {
+       png_warning(png_ptr, "sPLT chunk too long");
+       return;
+   }
+   new_palette.entries = (png_sPLT_entryp)png_malloc_warn(
+       png_ptr, new_palette.nentries * png_sizeof(png_sPLT_entry));
+   if (new_palette.entries == NULL)
+   {
+       png_warning(png_ptr, "sPLT chunk requires too much memory");
+       return;
+   }
+
+#ifndef PNG_NO_POINTER_INDEXING
+   for (i = 0; i < new_palette.nentries; i++)
+   {
+      png_sPLT_entryp pp = new_palette.entries + i;
+
+      if (new_palette.depth == 8)
+      {
+          pp->red = *entry_start++;
+          pp->green = *entry_start++;
+          pp->blue = *entry_start++;
+          pp->alpha = *entry_start++;
+      }
+      else
+      {
+          pp->red   = png_get_uint_16(entry_start); entry_start += 2;
+          pp->green = png_get_uint_16(entry_start); entry_start += 2;
+          pp->blue  = png_get_uint_16(entry_start); entry_start += 2;
+          pp->alpha = png_get_uint_16(entry_start); entry_start += 2;
+      }
+      pp->frequency = png_get_uint_16(entry_start); entry_start += 2;
+   }
+#else
+   pp = new_palette.entries;
+   for (i = 0; i < new_palette.nentries; i++)
+   {
+
+      if (new_palette.depth == 8)
+      {
+          pp[i].red   = *entry_start++;
+          pp[i].green = *entry_start++;
+          pp[i].blue  = *entry_start++;
+          pp[i].alpha = *entry_start++;
+      }
+      else
+      {
+          pp[i].red   = png_get_uint_16(entry_start); entry_start += 2;
+          pp[i].green = png_get_uint_16(entry_start); entry_start += 2;
+          pp[i].blue  = png_get_uint_16(entry_start); entry_start += 2;
+          pp[i].alpha = png_get_uint_16(entry_start); entry_start += 2;
+      }
+      pp->frequency = png_get_uint_16(entry_start); entry_start += 2;
+   }
+#endif
+
+   /* discard all chunk data except the name and stash that */
+   new_palette.name = (png_charp)chunkdata;
+
+   png_set_sPLT(png_ptr, info_ptr, &new_palette, 1);
+
+   png_free(png_ptr, chunkdata);
+   png_free(png_ptr, new_palette.entries);
+}
+#endif /* PNG_READ_sPLT_SUPPORTED */
+
+#if defined(PNG_READ_tRNS_SUPPORTED)
+void /* PRIVATE */
+png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_byte readbuf[PNG_MAX_PALETTE_LENGTH];
+
+   png_debug(1, "in png_handle_tRNS\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before tRNS");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid tRNS after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
+   {
+      png_warning(png_ptr, "Duplicate tRNS chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
+   {
+      png_byte buf[2];
+
+      if (length != 2)
+      {
+         png_warning(png_ptr, "Incorrect tRNS chunk length");
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+
+      png_crc_read(png_ptr, buf, 2);
+      png_ptr->num_trans = 1;
+      png_ptr->trans_values.gray = png_get_uint_16(buf);
+   }
+   else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
+   {
+      png_byte buf[6];
+
+      if (length != 6)
+      {
+         png_warning(png_ptr, "Incorrect tRNS chunk length");
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+      png_crc_read(png_ptr, buf, (png_size_t)length);
+      png_ptr->num_trans = 1;
+      png_ptr->trans_values.red = png_get_uint_16(buf);
+      png_ptr->trans_values.green = png_get_uint_16(buf + 2);
+      png_ptr->trans_values.blue = png_get_uint_16(buf + 4);
+   }
+   else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+   {
+      if (!(png_ptr->mode & PNG_HAVE_PLTE))
+      {
+         /* Should be an error, but we can cope with it. */
+         png_warning(png_ptr, "Missing PLTE before tRNS");
+      }
+      if (length > (png_uint_32)png_ptr->num_palette ||
+          length > PNG_MAX_PALETTE_LENGTH)
+      {
+         png_warning(png_ptr, "Incorrect tRNS chunk length");
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+      if (length == 0)
+      {
+         png_warning(png_ptr, "Zero length tRNS chunk");
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+      png_crc_read(png_ptr, readbuf, (png_size_t)length);
+      png_ptr->num_trans = (png_uint_16)length;
+   }
+   else
+   {
+      png_warning(png_ptr, "tRNS chunk not allowed with alpha channel");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   if (png_crc_finish(png_ptr, 0))
+      return;
+
+   png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans,
+      &(png_ptr->trans_values));
+}
+#endif
+
+#if defined(PNG_READ_bKGD_SUPPORTED)
+void /* PRIVATE */
+png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_size_t truelen;
+   png_byte buf[6];
+
+   png_debug(1, "in png_handle_bKGD\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before bKGD");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid bKGD after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+            !(png_ptr->mode & PNG_HAVE_PLTE))
+   {
+      png_warning(png_ptr, "Missing PLTE before bKGD");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD))
+   {
+      png_warning(png_ptr, "Duplicate bKGD chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      truelen = 1;
+   else if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
+      truelen = 6;
+   else
+      truelen = 2;
+
+   if (length != truelen)
+   {
+      png_warning(png_ptr, "Incorrect bKGD chunk length");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   png_crc_read(png_ptr, buf, truelen);
+   if (png_crc_finish(png_ptr, 0))
+      return;
+
+   /* We convert the index value into RGB components so that we can allow
+    * arbitrary RGB values for background when we have transparency, and
+    * so it is easy to determine the RGB values of the background color
+    * from the info_ptr struct. */
+   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+   {
+      png_ptr->background.index = buf[0];
+      if(info_ptr->num_palette)
+      {
+          if(buf[0] > info_ptr->num_palette)
+          {
+             png_warning(png_ptr, "Incorrect bKGD chunk index value");
+             return;
+          }
+          png_ptr->background.red =
+             (png_uint_16)png_ptr->palette[buf[0]].red;
+          png_ptr->background.green =
+             (png_uint_16)png_ptr->palette[buf[0]].green;
+          png_ptr->background.blue =
+             (png_uint_16)png_ptr->palette[buf[0]].blue;
+      }
+   }
+   else if (!(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) /* GRAY */
+   {
+      png_ptr->background.red =
+      png_ptr->background.green =
+      png_ptr->background.blue =
+      png_ptr->background.gray = png_get_uint_16(buf);
+   }
+   else
+   {
+      png_ptr->background.red = png_get_uint_16(buf);
+      png_ptr->background.green = png_get_uint_16(buf + 2);
+      png_ptr->background.blue = png_get_uint_16(buf + 4);
+   }
+
+   png_set_bKGD(png_ptr, info_ptr, &(png_ptr->background));
+}
+#endif
+
+#if defined(PNG_READ_hIST_SUPPORTED)
+void /* PRIVATE */
+png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   unsigned int num, i;
+   png_uint_16 readbuf[PNG_MAX_PALETTE_LENGTH];
+
+   png_debug(1, "in png_handle_hIST\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before hIST");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid hIST after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (!(png_ptr->mode & PNG_HAVE_PLTE))
+   {
+      png_warning(png_ptr, "Missing PLTE before hIST");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST))
+   {
+      png_warning(png_ptr, "Duplicate hIST chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   num = length / 2 ;
+   if (num != (unsigned int) png_ptr->num_palette || num >
+      (unsigned int) PNG_MAX_PALETTE_LENGTH)
+   {
+      png_warning(png_ptr, "Incorrect hIST chunk length");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   for (i = 0; i < num; i++)
+   {
+      png_byte buf[2];
+
+      png_crc_read(png_ptr, buf, 2);
+      readbuf[i] = png_get_uint_16(buf);
+   }
+
+   if (png_crc_finish(png_ptr, 0))
+      return;
+
+   png_set_hIST(png_ptr, info_ptr, readbuf);
+}
+#endif
+
+#if defined(PNG_READ_pHYs_SUPPORTED)
+void /* PRIVATE */
+png_handle_pHYs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_byte buf[9];
+   png_uint_32 res_x, res_y;
+   int unit_type;
+
+   png_debug(1, "in png_handle_pHYs\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before pHYs");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid pHYs after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   {
+      png_warning(png_ptr, "Duplicate pHYs chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   if (length != 9)
+   {
+      png_warning(png_ptr, "Incorrect pHYs chunk length");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   png_crc_read(png_ptr, buf, 9);
+   if (png_crc_finish(png_ptr, 0))
+      return;
+
+   res_x = png_get_uint_32(buf);
+   res_y = png_get_uint_32(buf + 4);
+   unit_type = buf[8];
+   png_set_pHYs(png_ptr, info_ptr, res_x, res_y, unit_type);
+}
+#endif
+
+#if defined(PNG_READ_oFFs_SUPPORTED)
+void /* PRIVATE */
+png_handle_oFFs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_byte buf[9];
+   png_int_32 offset_x, offset_y;
+   int unit_type;
+
+   png_debug(1, "in png_handle_oFFs\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before oFFs");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid oFFs after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   {
+      png_warning(png_ptr, "Duplicate oFFs chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   if (length != 9)
+   {
+      png_warning(png_ptr, "Incorrect oFFs chunk length");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   png_crc_read(png_ptr, buf, 9);
+   if (png_crc_finish(png_ptr, 0))
+      return;
+
+   offset_x = png_get_int_32(buf);
+   offset_y = png_get_int_32(buf + 4);
+   unit_type = buf[8];
+   png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y, unit_type);
+}
+#endif
+
+#if defined(PNG_READ_pCAL_SUPPORTED)
+/* read the pCAL chunk (described in the PNG Extensions document) */
+void /* PRIVATE */
+png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_charp purpose;
+   png_int_32 X0, X1;
+   png_byte type, nparams;
+   png_charp buf, units, endptr;
+   png_charpp params;
+   png_size_t slength;
+   int i;
+
+   png_debug(1, "in png_handle_pCAL\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before pCAL");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid pCAL after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL))
+   {
+      png_warning(png_ptr, "Duplicate pCAL chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   png_debug1(2, "Allocating and reading pCAL chunk data (%lu bytes)\n",
+      length + 1);
+   purpose = (png_charp)png_malloc_warn(png_ptr, length + 1);
+   if (purpose == NULL)
+     {
+       png_warning(png_ptr, "No memory for pCAL purpose.");
+       return;
+     }
+   slength = (png_size_t)length;
+   png_crc_read(png_ptr, (png_bytep)purpose, slength);
+
+   if (png_crc_finish(png_ptr, 0))
+   {
+      png_free(png_ptr, purpose);
+      return;
+   }
+
+   purpose[slength] = 0x00; /* null terminate the last string */
+
+   png_debug(3, "Finding end of pCAL purpose string\n");
+   for (buf = purpose; *buf; buf++)
+      /* empty loop */ ;
+
+   endptr = purpose + slength;
+
+   /* We need to have at least 12 bytes after the purpose string
+      in order to get the parameter information. */
+   if (endptr <= buf + 12)
+   {
+      png_warning(png_ptr, "Invalid pCAL data");
+      png_free(png_ptr, purpose);
+      return;
+   }
+
+   png_debug(3, "Reading pCAL X0, X1, type, nparams, and units\n");
+   X0 = png_get_int_32((png_bytep)buf+1);
+   X1 = png_get_int_32((png_bytep)buf+5);
+   type = buf[9];
+   nparams = buf[10];
+   units = buf + 11;
+
+   png_debug(3, "Checking pCAL equation type and number of parameters\n");
+   /* Check that we have the right number of parameters for known
+      equation types. */
+   if ((type == PNG_EQUATION_LINEAR && nparams != 2) ||
+       (type == PNG_EQUATION_BASE_E && nparams != 3) ||
+       (type == PNG_EQUATION_ARBITRARY && nparams != 3) ||
+       (type == PNG_EQUATION_HYPERBOLIC && nparams != 4))
+   {
+      png_warning(png_ptr, "Invalid pCAL parameters for equation type");
+      png_free(png_ptr, purpose);
+      return;
+   }
+   else if (type >= PNG_EQUATION_LAST)
+   {
+      png_warning(png_ptr, "Unrecognized equation type for pCAL chunk");
+   }
+
+   for (buf = units; *buf; buf++)
+      /* Empty loop to move past the units string. */ ;
+
+   png_debug(3, "Allocating pCAL parameters array\n");
+   params = (png_charpp)png_malloc_warn(png_ptr, (png_uint_32)(nparams
+      *png_sizeof(png_charp))) ;
+   if (params == NULL)
+     {
+       png_free(png_ptr, purpose);
+       png_warning(png_ptr, "No memory for pCAL params.");
+       return;
+     }
+
+   /* Get pointers to the start of each parameter string. */
+   for (i = 0; i < (int)nparams; i++)
+   {
+      buf++; /* Skip the null string terminator from previous parameter. */
+
+      png_debug1(3, "Reading pCAL parameter %d\n", i);
+      for (params[i] = buf; *buf != 0x00 && buf <= endptr; buf++)
+         /* Empty loop to move past each parameter string */ ;
+
+      /* Make sure we haven't run out of data yet */
+      if (buf > endptr)
+      {
+         png_warning(png_ptr, "Invalid pCAL data");
+         png_free(png_ptr, purpose);
+         png_free(png_ptr, params);
+         return;
+      }
+   }
+
+   png_set_pCAL(png_ptr, info_ptr, purpose, X0, X1, type, nparams,
+      units, params);
+
+   png_free(png_ptr, purpose);
+   png_free(png_ptr, params);
+}
+#endif
+
+#if defined(PNG_READ_sCAL_SUPPORTED)
+/* read the sCAL chunk */
+void /* PRIVATE */
+png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_charp buffer, ep;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   double width, height;
+   png_charp vp;
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   png_charp swidth, sheight;
+#endif
+#endif
+   png_size_t slength;
+
+   png_debug(1, "in png_handle_sCAL\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before sCAL");
+   else if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+      png_warning(png_ptr, "Invalid sCAL after IDAT");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sCAL))
+   {
+      png_warning(png_ptr, "Duplicate sCAL chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   png_debug1(2, "Allocating and reading sCAL chunk data (%lu bytes)\n",
+      length + 1);
+   buffer = (png_charp)png_malloc_warn(png_ptr, length + 1);
+   if (buffer == NULL)
+     {
+       png_warning(png_ptr, "Out of memory while processing sCAL chunk");
+       return;
+     }
+   slength = (png_size_t)length;
+   png_crc_read(png_ptr, (png_bytep)buffer, slength);
+
+   if (png_crc_finish(png_ptr, 0))
+   {
+      png_free(png_ptr, buffer);
+      return;
+   }
+
+   buffer[slength] = 0x00; /* null terminate the last string */
+
+   ep = buffer + 1;        /* skip unit byte */
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   width = strtod(ep, &vp);
+   if (*vp)
+   {
+       png_warning(png_ptr, "malformed width string in sCAL chunk");
+       return;
+   }
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   swidth = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1);
+   if (swidth == NULL)
+     {
+       png_warning(png_ptr, "Out of memory while processing sCAL chunk width");
+       return;
+     }
+   png_memcpy(swidth, ep, (png_size_t)png_strlen(ep));
+#endif
+#endif
+
+   for (ep = buffer; *ep; ep++)
+      /* empty loop */ ;
+   ep++;
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   height = strtod(ep, &vp);
+   if (*vp)
+   {
+       png_warning(png_ptr, "malformed height string in sCAL chunk");
+       return;
+   }
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   sheight = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1);
+   if (swidth == NULL)
+     {
+       png_warning(png_ptr, "Out of memory while processing sCAL chunk height");
+       return;
+     }
+   png_memcpy(sheight, ep, (png_size_t)png_strlen(ep));
+#endif
+#endif
+
+   if (buffer + slength < ep
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+      || width <= 0. || height <= 0.
+#endif
+      )
+   {
+      png_warning(png_ptr, "Invalid sCAL data");
+      png_free(png_ptr, buffer);
+#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
+      png_free(png_ptr, swidth);
+      png_free(png_ptr, sheight);
+#endif
+      return;
+   }
+
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   png_set_sCAL(png_ptr, info_ptr, buffer[0], width, height);
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   png_set_sCAL_s(png_ptr, info_ptr, buffer[0], swidth, sheight);
+#endif
+#endif
+
+   png_free(png_ptr, buffer);
+#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
+   png_free(png_ptr, swidth);
+   png_free(png_ptr, sheight);
+#endif
+}
+#endif
+
+#if defined(PNG_READ_tIME_SUPPORTED)
+void /* PRIVATE */
+png_handle_tIME(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_byte buf[7];
+   png_time mod_time;
+
+   png_debug(1, "in png_handle_tIME\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Out of place tIME chunk");
+   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME))
+   {
+      png_warning(png_ptr, "Duplicate tIME chunk");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   if (png_ptr->mode & PNG_HAVE_IDAT)
+      png_ptr->mode |= PNG_AFTER_IDAT;
+
+   if (length != 7)
+   {
+      png_warning(png_ptr, "Incorrect tIME chunk length");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
+   png_crc_read(png_ptr, buf, 7);
+   if (png_crc_finish(png_ptr, 0))
+      return;
+
+   mod_time.second = buf[6];
+   mod_time.minute = buf[5];
+   mod_time.hour = buf[4];
+   mod_time.day = buf[3];
+   mod_time.month = buf[2];
+   mod_time.year = png_get_uint_16(buf);
+
+   png_set_tIME(png_ptr, info_ptr, &mod_time);
+}
+#endif
+
+#if defined(PNG_READ_tEXt_SUPPORTED)
+/* Note: this does not properly handle chunks that are > 64K under DOS */
+void /* PRIVATE */
+png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_textp text_ptr;
+   png_charp key;
+   png_charp text;
+   png_uint_32 skip = 0;
+   png_size_t slength;
+   int ret;
+
+   png_debug(1, "in png_handle_tEXt\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before tEXt");
+
+   if (png_ptr->mode & PNG_HAVE_IDAT)
+      png_ptr->mode |= PNG_AFTER_IDAT;
+
+#ifdef PNG_MAX_MALLOC_64K
+   if (length > (png_uint_32)65535L)
+   {
+      png_warning(png_ptr, "tEXt chunk too large to fit in memory");
+      skip = length - (png_uint_32)65535L;
+      length = (png_uint_32)65535L;
+   }
+#endif
+
+   key = (png_charp)png_malloc_warn(png_ptr, length + 1);
+   if (key == NULL)
+   {
+     png_warning(png_ptr, "No memory to process text chunk.");
+     return;
+   }
+   slength = (png_size_t)length;
+   png_crc_read(png_ptr, (png_bytep)key, slength);
+
+   if (png_crc_finish(png_ptr, skip))
+   {
+      png_free(png_ptr, key);
+      return;
+   }
+
+   key[slength] = 0x00;
+
+   for (text = key; *text; text++)
+      /* empty loop to find end of key */ ;
+
+   if (text != key + slength)
+      text++;
+
+   text_ptr = (png_textp)png_malloc_warn(png_ptr,
+      (png_uint_32)png_sizeof(png_text));
+   if (text_ptr == NULL)
+   {
+     png_warning(png_ptr, "Not enough memory to process text chunk.");
+     png_free(png_ptr, key);
+     return;
+   }
+   text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
+   text_ptr->key = key;
+#ifdef PNG_iTXt_SUPPORTED
+   text_ptr->lang = NULL;
+   text_ptr->lang_key = NULL;
+   text_ptr->itxt_length = 0;
+#endif
+   text_ptr->text = text;
+   text_ptr->text_length = png_strlen(text);
+
+   ret=png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+   png_free(png_ptr, key);
+   png_free(png_ptr, text_ptr);
+   if (ret)
+     png_warning(png_ptr, "Insufficient memory to process text chunk.");
+}
+#endif
+
+#if defined(PNG_READ_zTXt_SUPPORTED)
+/* note: this does not correctly handle chunks that are > 64K under DOS */
+void /* PRIVATE */
+png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_textp text_ptr;
+   png_charp chunkdata;
+   png_charp text;
+   int comp_type;
+   int ret;
+   png_size_t slength, prefix_len, data_len;
+
+   png_debug(1, "in png_handle_zTXt\n");
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before zTXt");
+
+   if (png_ptr->mode & PNG_HAVE_IDAT)
+      png_ptr->mode |= PNG_AFTER_IDAT;
+
+#ifdef PNG_MAX_MALLOC_64K
+   /* We will no doubt have problems with chunks even half this size, but
+      there is no hard and fast rule to tell us where to stop. */
+   if (length > (png_uint_32)65535L)
+   {
+     png_warning(png_ptr,"zTXt chunk too large to fit in memory");
+     png_crc_finish(png_ptr, length);
+     return;
+   }
+#endif
+
+   chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
+   if (chunkdata == NULL)
+   {
+     png_warning(png_ptr,"Out of memory processing zTXt chunk.");
+     return;
+   }
+   slength = (png_size_t)length;
+   png_crc_read(png_ptr, (png_bytep)chunkdata, slength);
+   if (png_crc_finish(png_ptr, 0))
+   {
+      png_free(png_ptr, chunkdata);
+      return;
+   }
+
+   chunkdata[slength] = 0x00;
+
+   for (text = chunkdata; *text; text++)
+      /* empty loop */ ;
+
+   /* zTXt must have some text after the chunkdataword */
+   if (text == chunkdata + slength)
+   {
+      comp_type = PNG_TEXT_COMPRESSION_NONE;
+      png_warning(png_ptr, "Zero length zTXt chunk");
+   }
+   else
+   {
+       comp_type = *(++text);
+       if (comp_type != PNG_TEXT_COMPRESSION_zTXt)
+       {
+          png_warning(png_ptr, "Unknown compression type in zTXt chunk");
+          comp_type = PNG_TEXT_COMPRESSION_zTXt;
+       }
+       text++;        /* skip the compression_method byte */
+   }
+   prefix_len = text - chunkdata;
+
+   chunkdata = (png_charp)png_decompress_chunk(png_ptr, comp_type, chunkdata,
+                                    (png_size_t)length, prefix_len, &data_len);
+
+   text_ptr = (png_textp)png_malloc_warn(png_ptr,
+     (png_uint_32)png_sizeof(png_text));
+   if (text_ptr == NULL)
+   {
+     png_warning(png_ptr,"Not enough memory to process zTXt chunk.");
+     png_free(png_ptr, chunkdata);
+     return;
+   }
+   text_ptr->compression = comp_type;
+   text_ptr->key = chunkdata;
+#ifdef PNG_iTXt_SUPPORTED
+   text_ptr->lang = NULL;
+   text_ptr->lang_key = NULL;
+   text_ptr->itxt_length = 0;
+#endif
+   text_ptr->text = chunkdata + prefix_len;
+   text_ptr->text_length = data_len;
+
+   ret=png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+   png_free(png_ptr, text_ptr);
+   png_free(png_ptr, chunkdata);
+   if (ret)
+     png_error(png_ptr, "Insufficient memory to store zTXt chunk.");
+}
+#endif
+
+#if defined(PNG_READ_iTXt_SUPPORTED)
+/* note: this does not correctly handle chunks that are > 64K under DOS */
+void /* PRIVATE */
+png_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_textp text_ptr;
+   png_charp chunkdata;
+   png_charp key, lang, text, lang_key;
+   int comp_flag;
+   int comp_type = 0;
+   int ret;
+   png_size_t slength, prefix_len, data_len;
+
+   png_debug(1, "in png_handle_iTXt\n");
+
+   if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      png_error(png_ptr, "Missing IHDR before iTXt");
+
+   if (png_ptr->mode & PNG_HAVE_IDAT)
+      png_ptr->mode |= PNG_AFTER_IDAT;
+
+#ifdef PNG_MAX_MALLOC_64K
+   /* We will no doubt have problems with chunks even half this size, but
+      there is no hard and fast rule to tell us where to stop. */
+   if (length > (png_uint_32)65535L)
+   {
+     png_warning(png_ptr,"iTXt chunk too large to fit in memory");
+     png_crc_finish(png_ptr, length);
+     return;
+   }
+#endif
+
+   chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
+   if (chunkdata == NULL)
+   {
+     png_warning(png_ptr, "No memory to process iTXt chunk.");
+     return;
+   }
+   slength = (png_size_t)length;
+   png_crc_read(png_ptr, (png_bytep)chunkdata, slength);
+   if (png_crc_finish(png_ptr, 0))
+   {
+      png_free(png_ptr, chunkdata);
+      return;
+   }
+
+   chunkdata[slength] = 0x00;
+
+   for (lang = chunkdata; *lang; lang++)
+      /* empty loop */ ;
+   lang++;        /* skip NUL separator */
+
+   /* iTXt must have a language tag (possibly empty), two compression bytes,
+      translated keyword (possibly empty), and possibly some text after the
+      keyword */
+
+   if (lang >= chunkdata + slength)
+   {
+      comp_flag = PNG_TEXT_COMPRESSION_NONE;
+      png_warning(png_ptr, "Zero length iTXt chunk");
+   }
+   else
+   {
+       comp_flag = *lang++;
+       comp_type = *lang++;
+   }
+
+   for (lang_key = lang; *lang_key; lang_key++)
+      /* empty loop */ ;
+   lang_key++;        /* skip NUL separator */
+
+   for (text = lang_key; *text; text++)
+      /* empty loop */ ;
+   text++;        /* skip NUL separator */
+
+   prefix_len = text - chunkdata;
+
+   key=chunkdata;
+   if (comp_flag)
+       chunkdata = png_decompress_chunk(png_ptr, comp_type, chunkdata,
+          (size_t)length, prefix_len, &data_len);
+   else
+       data_len=png_strlen(chunkdata + prefix_len);
+   text_ptr = (png_textp)png_malloc_warn(png_ptr,
+      (png_uint_32)png_sizeof(png_text));
+   if (text_ptr == NULL)
+   {
+     png_warning(png_ptr,"Not enough memory to process iTXt chunk.");
+     png_free(png_ptr, chunkdata);
+     return;
+   }
+   text_ptr->compression = (int)comp_flag + 1;
+   text_ptr->lang_key = chunkdata+(lang_key-key);
+   text_ptr->lang = chunkdata+(lang-key);
+   text_ptr->itxt_length = data_len;
+   text_ptr->text_length = 0;
+   text_ptr->key = chunkdata;
+   text_ptr->text = chunkdata + prefix_len;
+
+   ret=png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+   png_free(png_ptr, text_ptr);
+   png_free(png_ptr, chunkdata);
+   if (ret)
+     png_error(png_ptr, "Insufficient memory to store iTXt chunk.");
+}
+#endif
+
+/* This function is called when we haven't found a handler for a
+   chunk.  If there isn't a problem with the chunk itself (ie bad
+   chunk name, CRC, or a critical chunk), the chunk is silently ignored
+   -- unless the PNG_FLAG_UNKNOWN_CHUNKS_SUPPORTED flag is on in which
+   case it will be saved away to be written out later. */
+void /* PRIVATE */
+png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+   png_uint_32 skip = 0;
+
+   png_debug(1, "in png_handle_unknown\n");
+
+   if (png_ptr->mode & PNG_HAVE_IDAT)
+   {
+#ifdef PNG_USE_LOCAL_ARRAYS
+      PNG_IDAT;
+#endif
+      if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))  /* not an IDAT */
+         png_ptr->mode |= PNG_AFTER_IDAT;
+   }
+
+   png_check_chunk_name(png_ptr, png_ptr->chunk_name);
+
+   if (!(png_ptr->chunk_name[0] & 0x20))
+   {
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+      if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
+           PNG_HANDLE_CHUNK_ALWAYS
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+           && png_ptr->read_user_chunk_fn == NULL
+#endif
+        )
+#endif
+          png_chunk_error(png_ptr, "unknown critical chunk");
+   }
+
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+   if (png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS)
+   {
+       png_unknown_chunk chunk;
+
+#ifdef PNG_MAX_MALLOC_64K
+       if (length > (png_uint_32)65535L)
+       {
+           png_warning(png_ptr, "unknown chunk too large to fit in memory");
+           skip = length - (png_uint_32)65535L;
+           length = (png_uint_32)65535L;
+       }
+#endif
+       png_strcpy((png_charp)chunk.name, (png_charp)png_ptr->chunk_name);
+       chunk.data = (png_bytep)png_malloc(png_ptr, length);
+       chunk.size = (png_size_t)length;
+       png_crc_read(png_ptr, (png_bytep)chunk.data, length);
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+       if(png_ptr->read_user_chunk_fn != NULL)
+       {
+          /* callback to user unknown chunk handler */
+          if ((*(png_ptr->read_user_chunk_fn)) (png_ptr, &chunk) <= 0)
+          {
+             if (!(png_ptr->chunk_name[0] & 0x20))
+                if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
+                     PNG_HANDLE_CHUNK_ALWAYS)
+                 {
+                   png_free(png_ptr, chunk.data);
+                   png_chunk_error(png_ptr, "unknown critical chunk");
+                 }
+             png_set_unknown_chunks(png_ptr, info_ptr, &chunk, 1);
+          }
+       }
+       else
+#endif
+          png_set_unknown_chunks(png_ptr, info_ptr, &chunk, 1);
+       png_free(png_ptr, chunk.data);
+   }
+   else
+#endif
+      skip = length;
+
+   png_crc_finish(png_ptr, skip);
+
+#if !defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+   if (&info_ptr == NULL) /* quiet compiler warnings about unused info_ptr */
+      return;
+#endif
+}
+
+/* This function is called to verify that a chunk name is valid.
+   This function can't have the "critical chunk check" incorporated
+   into it, since in the future we will need to be able to call user
+   functions to handle unknown critical chunks after we check that
+   the chunk name itself is valid. */
+
+#define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97))
+
+void /* PRIVATE */
+png_check_chunk_name(png_structp png_ptr, png_bytep chunk_name)
+{
+   png_debug(1, "in png_check_chunk_name\n");
+   if (isnonalpha(chunk_name[0]) || isnonalpha(chunk_name[1]) ||
+       isnonalpha(chunk_name[2]) || isnonalpha(chunk_name[3]))
+   {
+      png_chunk_error(png_ptr, "invalid chunk type");
+   }
+}
+
+/* Combines the row recently read in with the existing pixels in the
+   row.  This routine takes care of alpha and transparency if requested.
+   This routine also handles the two methods of progressive display
+   of interlaced images, depending on the mask value.
+   The mask value describes which pixels are to be combined with
+   the row.  The pattern always repeats every 8 pixels, so just 8
+   bits are needed.  A one indicates the pixel is to be combined,
+   a zero indicates the pixel is to be skipped.  This is in addition
+   to any alpha or transparency value associated with the pixel.  If
+   you want all pixels to be combined, pass 0xff (255) in mask.  */
+#ifndef PNG_HAVE_ASSEMBLER_COMBINE_ROW
+void /* PRIVATE */
+png_combine_row(png_structp png_ptr, png_bytep row, int mask)
+{
+   png_debug(1,"in png_combine_row\n");
+   if (mask == 0xff)
+   {
+      png_memcpy(row, png_ptr->row_buf + 1,
+         PNG_ROWBYTES(png_ptr->row_info.pixel_depth, png_ptr->width));
+   }
+   else
+   {
+      switch (png_ptr->row_info.pixel_depth)
+      {
+         case 1:
+         {
+            png_bytep sp = png_ptr->row_buf + 1;
+            png_bytep dp = row;
+            int s_inc, s_start, s_end;
+            int m = 0x80;
+            int shift;
+            png_uint_32 i;
+            png_uint_32 row_width = png_ptr->width;
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (png_ptr->transformations & PNG_PACKSWAP)
+            {
+                s_start = 0;
+                s_end = 7;
+                s_inc = 1;
+            }
+            else
+#endif
+            {
+                s_start = 7;
+                s_end = 0;
+                s_inc = -1;
+            }
+
+            shift = s_start;
+
+            for (i = 0; i < row_width; i++)
+            {
+               if (m & mask)
+               {
+                  int value;
+
+                  value = (*sp >> shift) & 0x01;
+                  *dp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff);
+                  *dp |= (png_byte)(value << shift);
+               }
+
+               if (shift == s_end)
+               {
+                  shift = s_start;
+                  sp++;
+                  dp++;
+               }
+               else
+                  shift += s_inc;
+
+               if (m == 1)
+                  m = 0x80;
+               else
+                  m >>= 1;
+            }
+            break;
+         }
+         case 2:
+         {
+            png_bytep sp = png_ptr->row_buf + 1;
+            png_bytep dp = row;
+            int s_start, s_end, s_inc;
+            int m = 0x80;
+            int shift;
+            png_uint_32 i;
+            png_uint_32 row_width = png_ptr->width;
+            int value;
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (png_ptr->transformations & PNG_PACKSWAP)
+            {
+               s_start = 0;
+               s_end = 6;
+               s_inc = 2;
+            }
+            else
+#endif
+            {
+               s_start = 6;
+               s_end = 0;
+               s_inc = -2;
+            }
+
+            shift = s_start;
+
+            for (i = 0; i < row_width; i++)
+            {
+               if (m & mask)
+               {
+                  value = (*sp >> shift) & 0x03;
+                  *dp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
+                  *dp |= (png_byte)(value << shift);
+               }
+
+               if (shift == s_end)
+               {
+                  shift = s_start;
+                  sp++;
+                  dp++;
+               }
+               else
+                  shift += s_inc;
+               if (m == 1)
+                  m = 0x80;
+               else
+                  m >>= 1;
+            }
+            break;
+         }
+         case 4:
+         {
+            png_bytep sp = png_ptr->row_buf + 1;
+            png_bytep dp = row;
+            int s_start, s_end, s_inc;
+            int m = 0x80;
+            int shift;
+            png_uint_32 i;
+            png_uint_32 row_width = png_ptr->width;
+            int value;
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (png_ptr->transformations & PNG_PACKSWAP)
+            {
+               s_start = 0;
+               s_end = 4;
+               s_inc = 4;
+            }
+            else
+#endif
+            {
+               s_start = 4;
+               s_end = 0;
+               s_inc = -4;
+            }
+            shift = s_start;
+
+            for (i = 0; i < row_width; i++)
+            {
+               if (m & mask)
+               {
+                  value = (*sp >> shift) & 0xf;
+                  *dp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
+                  *dp |= (png_byte)(value << shift);
+               }
+
+               if (shift == s_end)
+               {
+                  shift = s_start;
+                  sp++;
+                  dp++;
+               }
+               else
+                  shift += s_inc;
+               if (m == 1)
+                  m = 0x80;
+               else
+                  m >>= 1;
+            }
+            break;
+         }
+         default:
+         {
+            png_bytep sp = png_ptr->row_buf + 1;
+            png_bytep dp = row;
+            png_size_t pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
+            png_uint_32 i;
+            png_uint_32 row_width = png_ptr->width;
+            png_byte m = 0x80;
+
+
+            for (i = 0; i < row_width; i++)
+            {
+               if (m & mask)
+               {
+                  png_memcpy(dp, sp, pixel_bytes);
+               }
+
+               sp += pixel_bytes;
+               dp += pixel_bytes;
+
+               if (m == 1)
+                  m = 0x80;
+               else
+                  m >>= 1;
+            }
+            break;
+         }
+      }
+   }
+}
+#endif /* !PNG_HAVE_ASSEMBLER_COMBINE_ROW */
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+#ifndef PNG_HAVE_ASSEMBLER_READ_INTERLACE   /* else in pngvcrd.c, pnggccrd.c */
+/* OLD pre-1.0.9 interface:
+void png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
+   png_uint_32 transformations)
+ */
+void /* PRIVATE */
+png_do_read_interlace(png_structp png_ptr)
+{
+   png_row_infop row_info = &(png_ptr->row_info);
+   png_bytep row = png_ptr->row_buf + 1;
+   int pass = png_ptr->pass;
+   png_uint_32 transformations = png_ptr->transformations;
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+   /* offset to next interlace block */
+   const int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+#endif
+
+   png_debug(1,"in png_do_read_interlace (stock C version)\n");
+   if (row != NULL && row_info != NULL)
+   {
+      png_uint_32 final_width;
+
+      final_width = row_info->width * png_pass_inc[pass];
+
+      switch (row_info->pixel_depth)
+      {
+         case 1:
+         {
+            png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 3);
+            png_bytep dp = row + (png_size_t)((final_width - 1) >> 3);
+            int sshift, dshift;
+            int s_start, s_end, s_inc;
+            int jstop = png_pass_inc[pass];
+            png_byte v;
+            png_uint_32 i;
+            int j;
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (transformations & PNG_PACKSWAP)
+            {
+                sshift = (int)((row_info->width + 7) & 0x07);
+                dshift = (int)((final_width + 7) & 0x07);
+                s_start = 7;
+                s_end = 0;
+                s_inc = -1;
+            }
+            else
+#endif
+            {
+                sshift = 7 - (int)((row_info->width + 7) & 0x07);
+                dshift = 7 - (int)((final_width + 7) & 0x07);
+                s_start = 0;
+                s_end = 7;
+                s_inc = 1;
+            }
+
+            for (i = 0; i < row_info->width; i++)
+            {
+               v = (png_byte)((*sp >> sshift) & 0x01);
+               for (j = 0; j < jstop; j++)
+               {
+                  *dp &= (png_byte)((0x7f7f >> (7 - dshift)) & 0xff);
+                  *dp |= (png_byte)(v << dshift);
+                  if (dshift == s_end)
+                  {
+                     dshift = s_start;
+                     dp--;
+                  }
+                  else
+                     dshift += s_inc;
+               }
+               if (sshift == s_end)
+               {
+                  sshift = s_start;
+                  sp--;
+               }
+               else
+                  sshift += s_inc;
+            }
+            break;
+         }
+         case 2:
+         {
+            png_bytep sp = row + (png_uint_32)((row_info->width - 1) >> 2);
+            png_bytep dp = row + (png_uint_32)((final_width - 1) >> 2);
+            int sshift, dshift;
+            int s_start, s_end, s_inc;
+            int jstop = png_pass_inc[pass];
+            png_uint_32 i;
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (transformations & PNG_PACKSWAP)
+            {
+               sshift = (int)(((row_info->width + 3) & 0x03) << 1);
+               dshift = (int)(((final_width + 3) & 0x03) << 1);
+               s_start = 6;
+               s_end = 0;
+               s_inc = -2;
+            }
+            else
+#endif
+            {
+               sshift = (int)((3 - ((row_info->width + 3) & 0x03)) << 1);
+               dshift = (int)((3 - ((final_width + 3) & 0x03)) << 1);
+               s_start = 0;
+               s_end = 6;
+               s_inc = 2;
+            }
+
+            for (i = 0; i < row_info->width; i++)
+            {
+               png_byte v;
+               int j;
+
+               v = (png_byte)((*sp >> sshift) & 0x03);
+               for (j = 0; j < jstop; j++)
+               {
+                  *dp &= (png_byte)((0x3f3f >> (6 - dshift)) & 0xff);
+                  *dp |= (png_byte)(v << dshift);
+                  if (dshift == s_end)
+                  {
+                     dshift = s_start;
+                     dp--;
+                  }
+                  else
+                     dshift += s_inc;
+               }
+               if (sshift == s_end)
+               {
+                  sshift = s_start;
+                  sp--;
+               }
+               else
+                  sshift += s_inc;
+            }
+            break;
+         }
+         case 4:
+         {
+            png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 1);
+            png_bytep dp = row + (png_size_t)((final_width - 1) >> 1);
+            int sshift, dshift;
+            int s_start, s_end, s_inc;
+            png_uint_32 i;
+            int jstop = png_pass_inc[pass];
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (transformations & PNG_PACKSWAP)
+            {
+               sshift = (int)(((row_info->width + 1) & 0x01) << 2);
+               dshift = (int)(((final_width + 1) & 0x01) << 2);
+               s_start = 4;
+               s_end = 0;
+               s_inc = -4;
+            }
+            else
+#endif
+            {
+               sshift = (int)((1 - ((row_info->width + 1) & 0x01)) << 2);
+               dshift = (int)((1 - ((final_width + 1) & 0x01)) << 2);
+               s_start = 0;
+               s_end = 4;
+               s_inc = 4;
+            }
+
+            for (i = 0; i < row_info->width; i++)
+            {
+               png_byte v = (png_byte)((*sp >> sshift) & 0xf);
+               int j;
+
+               for (j = 0; j < jstop; j++)
+               {
+                  *dp &= (png_byte)((0xf0f >> (4 - dshift)) & 0xff);
+                  *dp |= (png_byte)(v << dshift);
+                  if (dshift == s_end)
+                  {
+                     dshift = s_start;
+                     dp--;
+                  }
+                  else
+                     dshift += s_inc;
+               }
+               if (sshift == s_end)
+               {
+                  sshift = s_start;
+                  sp--;
+               }
+               else
+                  sshift += s_inc;
+            }
+            break;
+         }
+         default:
+         {
+            png_size_t pixel_bytes = (row_info->pixel_depth >> 3);
+            png_bytep sp = row + (png_size_t)(row_info->width - 1) * pixel_bytes;
+            png_bytep dp = row + (png_size_t)(final_width - 1) * pixel_bytes;
+
+            int jstop = png_pass_inc[pass];
+            png_uint_32 i;
+
+            for (i = 0; i < row_info->width; i++)
+            {
+               png_byte v[8];
+               int j;
+
+               png_memcpy(v, sp, pixel_bytes);
+               for (j = 0; j < jstop; j++)
+               {
+                  png_memcpy(dp, v, pixel_bytes);
+                  dp -= pixel_bytes;
+               }
+               sp -= pixel_bytes;
+            }
+            break;
+         }
+      }
+      row_info->width = final_width;
+      row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,final_width);
+   }
+#if !defined(PNG_READ_PACKSWAP_SUPPORTED)
+   if (&transformations == NULL) /* silence compiler warning */
+      return;
+#endif
+}
+#endif /* !PNG_HAVE_ASSEMBLER_READ_INTERLACE */
+#endif /* PNG_READ_INTERLACING_SUPPORTED */
+
+#ifndef PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+void /* PRIVATE */
+png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
+   png_bytep prev_row, int filter)
+{
+   png_debug(1, "in png_read_filter_row\n");
+   png_debug2(2,"row = %lu, filter = %d\n", png_ptr->row_number, filter);
+   switch (filter)
+   {
+      case PNG_FILTER_VALUE_NONE:
+         break;
+      case PNG_FILTER_VALUE_SUB:
+      {
+         png_uint_32 i;
+         png_uint_32 istop = row_info->rowbytes;
+         png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+         png_bytep rp = row + bpp;
+         png_bytep lp = row;
+
+         for (i = bpp; i < istop; i++)
+         {
+            *rp = (png_byte)(((int)(*rp) + (int)(*lp++)) & 0xff);
+            rp++;
+         }
+         break;
+      }
+      case PNG_FILTER_VALUE_UP:
+      {
+         png_uint_32 i;
+         png_uint_32 istop = row_info->rowbytes;
+         png_bytep rp = row;
+         png_bytep pp = prev_row;
+
+         for (i = 0; i < istop; i++)
+         {
+            *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
+            rp++;
+         }
+         break;
+      }
+      case PNG_FILTER_VALUE_AVG:
+      {
+         png_uint_32 i;
+         png_bytep rp = row;
+         png_bytep pp = prev_row;
+         png_bytep lp = row;
+         png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+         png_uint_32 istop = row_info->rowbytes - bpp;
+
+         for (i = 0; i < bpp; i++)
+         {
+            *rp = (png_byte)(((int)(*rp) +
+               ((int)(*pp++) / 2 )) & 0xff);
+            rp++;
+         }
+
+         for (i = 0; i < istop; i++)
+         {
+            *rp = (png_byte)(((int)(*rp) +
+               (int)(*pp++ + *lp++) / 2 ) & 0xff);
+            rp++;
+         }
+         break;
+      }
+      case PNG_FILTER_VALUE_PAETH:
+      {
+         png_uint_32 i;
+         png_bytep rp = row;
+         png_bytep pp = prev_row;
+         png_bytep lp = row;
+         png_bytep cp = prev_row;
+         png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+         png_uint_32 istop=row_info->rowbytes - bpp;
+
+         for (i = 0; i < bpp; i++)
+         {
+            *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
+            rp++;
+         }
+
+         for (i = 0; i < istop; i++)   /* use leftover rp,pp */
+         {
+            int a, b, c, pa, pb, pc, p;
+
+            a = *lp++;
+            b = *pp++;
+            c = *cp++;
+
+            p = b - c;
+            pc = a - c;
+
+#ifdef PNG_USE_ABS
+            pa = abs(p);
+            pb = abs(pc);
+            pc = abs(p + pc);
+#else
+            pa = p < 0 ? -p : p;
+            pb = pc < 0 ? -pc : pc;
+            pc = (p + pc) < 0 ? -(p + pc) : p + pc;
+#endif
+
+            /*
+               if (pa <= pb && pa <= pc)
+                  p = a;
+               else if (pb <= pc)
+                  p = b;
+               else
+                  p = c;
+             */
+
+            p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
+
+            *rp = (png_byte)(((int)(*rp) + p) & 0xff);
+            rp++;
+         }
+         break;
+      }
+      default:
+         png_warning(png_ptr, "Ignoring bad adaptive filter type");
+         *row=0;
+         break;
+   }
+}
+#endif /* !PNG_HAVE_ASSEMBLER_READ_FILTER_ROW */
+
+void /* PRIVATE */
+png_read_finish_row(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+   /* start of interlace block */
+   const int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+
+   /* offset to next interlace block */
+   const int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+
+   /* start of interlace block in the y direction */
+   const int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+
+   /* offset to next interlace block in the y direction */
+   const int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+
+   png_debug(1, "in png_read_finish_row\n");
+   png_ptr->row_number++;
+   if (png_ptr->row_number < png_ptr->num_rows)
+      return;
+
+   if (png_ptr->interlaced)
+   {
+      png_ptr->row_number = 0;
+      png_memset_check(png_ptr, png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
+      do
+      {
+         png_ptr->pass++;
+         if (png_ptr->pass >= 7)
+            break;
+         png_ptr->iwidth = (png_ptr->width +
+            png_pass_inc[png_ptr->pass] - 1 -
+            png_pass_start[png_ptr->pass]) /
+            png_pass_inc[png_ptr->pass];
+
+         png_ptr->irowbytes = PNG_ROWBYTES(png_ptr->pixel_depth,
+            png_ptr->iwidth) + 1;
+
+         if (!(png_ptr->transformations & PNG_INTERLACE))
+         {
+            png_ptr->num_rows = (png_ptr->height +
+               png_pass_yinc[png_ptr->pass] - 1 -
+               png_pass_ystart[png_ptr->pass]) /
+               png_pass_yinc[png_ptr->pass];
+            if (!(png_ptr->num_rows))
+               continue;
+         }
+         else  /* if (png_ptr->transformations & PNG_INTERLACE) */
+            break;
+      } while (png_ptr->iwidth == 0);
+
+      if (png_ptr->pass < 7)
+         return;
+   }
+
+   if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
+   {
+#ifdef PNG_USE_LOCAL_ARRAYS
+      PNG_IDAT;
+#endif
+      char extra;
+      int ret;
+
+      png_ptr->zstream.next_out = (Byte *)&extra;
+      png_ptr->zstream.avail_out = (uInt)1;
+      for(;;)
+      {
+         if (!(png_ptr->zstream.avail_in))
+         {
+            while (!png_ptr->idat_size)
+            {
+               png_byte chunk_length[4];
+
+               png_crc_finish(png_ptr, 0);
+
+               png_read_data(png_ptr, chunk_length, 4);
+               png_ptr->idat_size = png_get_uint_31(png_ptr, chunk_length);
+               png_reset_crc(png_ptr);
+               png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+               if (png_memcmp(png_ptr->chunk_name, (png_bytep)png_IDAT, 4))
+                  png_error(png_ptr, "Not enough image data");
+
+            }
+            png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;
+            png_ptr->zstream.next_in = png_ptr->zbuf;
+            if (png_ptr->zbuf_size > png_ptr->idat_size)
+               png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
+            png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zstream.avail_in);
+            png_ptr->idat_size -= png_ptr->zstream.avail_in;
+         }
+         ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+         if (ret == Z_STREAM_END)
+         {
+            if (!(png_ptr->zstream.avail_out) || png_ptr->zstream.avail_in ||
+               png_ptr->idat_size)
+               png_warning(png_ptr, "Extra compressed data");
+            png_ptr->mode |= PNG_AFTER_IDAT;
+            png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
+            break;
+         }
+         if (ret != Z_OK)
+            png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
+                      "Decompression Error");
+
+         if (!(png_ptr->zstream.avail_out))
+         {
+            png_warning(png_ptr, "Extra compressed data.");
+            png_ptr->mode |= PNG_AFTER_IDAT;
+            png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
+            break;
+         }
+
+      }
+      png_ptr->zstream.avail_out = 0;
+   }
+
+   if (png_ptr->idat_size || png_ptr->zstream.avail_in)
+      png_warning(png_ptr, "Extra compression data");
+
+   inflateReset(&png_ptr->zstream);
+
+   png_ptr->mode |= PNG_AFTER_IDAT;
+}
+
+void /* PRIVATE */
+png_read_start_row(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+   /* start of interlace block */
+   const int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+
+   /* offset to next interlace block */
+   const int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+
+   /* start of interlace block in the y direction */
+   const int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+
+   /* offset to next interlace block in the y direction */
+   const int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+
+   int max_pixel_depth;
+   png_uint_32 row_bytes;
+
+   png_debug(1, "in png_read_start_row\n");
+   png_ptr->zstream.avail_in = 0;
+   png_init_read_transformations(png_ptr);
+   if (png_ptr->interlaced)
+   {
+      if (!(png_ptr->transformations & PNG_INTERLACE))
+         png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
+            png_pass_ystart[0]) / png_pass_yinc[0];
+      else
+         png_ptr->num_rows = png_ptr->height;
+
+      png_ptr->iwidth = (png_ptr->width +
+         png_pass_inc[png_ptr->pass] - 1 -
+         png_pass_start[png_ptr->pass]) /
+         png_pass_inc[png_ptr->pass];
+
+         row_bytes = PNG_ROWBYTES(png_ptr->pixel_depth,png_ptr->iwidth) + 1;
+
+         png_ptr->irowbytes = (png_size_t)row_bytes;
+         if((png_uint_32)png_ptr->irowbytes != row_bytes)
+            png_error(png_ptr, "Rowbytes overflow in png_read_start_row");
+   }
+   else
+   {
+      png_ptr->num_rows = png_ptr->height;
+      png_ptr->iwidth = png_ptr->width;
+      png_ptr->irowbytes = png_ptr->rowbytes + 1;
+   }
+   max_pixel_depth = png_ptr->pixel_depth;
+
+#if defined(PNG_READ_PACK_SUPPORTED)
+   if ((png_ptr->transformations & PNG_PACK) && png_ptr->bit_depth < 8)
+      max_pixel_depth = 8;
+#endif
+
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+   if (png_ptr->transformations & PNG_EXPAND)
+   {
+      if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      {
+         if (png_ptr->num_trans)
+            max_pixel_depth = 32;
+         else
+            max_pixel_depth = 24;
+      }
+      else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
+      {
+         if (max_pixel_depth < 8)
+            max_pixel_depth = 8;
+         if (png_ptr->num_trans)
+            max_pixel_depth *= 2;
+      }
+      else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
+      {
+         if (png_ptr->num_trans)
+         {
+            max_pixel_depth *= 4;
+            max_pixel_depth /= 3;
+         }
+      }
+   }
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED)
+   if (png_ptr->transformations & (PNG_FILLER))
+   {
+      if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+         max_pixel_depth = 32;
+      else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
+      {
+         if (max_pixel_depth <= 8)
+            max_pixel_depth = 16;
+         else
+            max_pixel_depth = 32;
+      }
+      else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
+      {
+         if (max_pixel_depth <= 32)
+            max_pixel_depth = 32;
+         else
+            max_pixel_depth = 64;
+      }
+   }
+#endif
+
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+   if (png_ptr->transformations & PNG_GRAY_TO_RGB)
+   {
+      if (
+#if defined(PNG_READ_EXPAND_SUPPORTED)
+        (png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND)) ||
+#endif
+#if defined(PNG_READ_FILLER_SUPPORTED)
+        (png_ptr->transformations & (PNG_FILLER)) ||
+#endif
+        png_ptr->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      {
+         if (max_pixel_depth <= 16)
+            max_pixel_depth = 32;
+         else
+            max_pixel_depth = 64;
+      }
+      else
+      {
+         if (max_pixel_depth <= 8)
+           {
+             if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+               max_pixel_depth = 32;
+             else
+               max_pixel_depth = 24;
+           }
+         else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+            max_pixel_depth = 64;
+         else
+            max_pixel_depth = 48;
+      }
+   }
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) && \
+defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+   if(png_ptr->transformations & PNG_USER_TRANSFORM)
+     {
+       int user_pixel_depth=png_ptr->user_transform_depth*
+         png_ptr->user_transform_channels;
+       if(user_pixel_depth > max_pixel_depth)
+         max_pixel_depth=user_pixel_depth;
+     }
+#endif
+
+   /* align the width on the next larger 8 pixels.  Mainly used
+      for interlacing */
+   row_bytes = ((png_ptr->width + 7) & ~((png_uint_32)7));
+   /* calculate the maximum bytes needed, adding a byte and a pixel
+      for safety's sake */
+   row_bytes = PNG_ROWBYTES(max_pixel_depth,row_bytes) +
+      1 + ((max_pixel_depth + 7) >> 3);
+#ifdef PNG_MAX_MALLOC_64K
+   if (row_bytes > (png_uint_32)65536L)
+      png_error(png_ptr, "This image requires a row greater than 64KB");
+#endif
+   png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, row_bytes+64);
+   png_ptr->row_buf = png_ptr->big_row_buf+32;
+#if defined(PNG_DEBUG) && defined(PNG_USE_PNGGCCRD)
+   png_ptr->row_buf_size = row_bytes;
+#endif
+
+#ifdef PNG_MAX_MALLOC_64K
+   if ((png_uint_32)png_ptr->rowbytes + 1 > (png_uint_32)65536L)
+      png_error(png_ptr, "This image requires a row greater than 64KB");
+#endif
+   if ((png_uint_32)png_ptr->rowbytes > PNG_SIZE_MAX - 1)
+      png_error(png_ptr, "Row has too many bytes to allocate in memory.");
+   png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)(
+      png_ptr->rowbytes + 1));
+
+   png_memset_check(png_ptr, png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
+
+   png_debug1(3, "width = %lu,\n", png_ptr->width);
+   png_debug1(3, "height = %lu,\n", png_ptr->height);
+   png_debug1(3, "iwidth = %lu,\n", png_ptr->iwidth);
+   png_debug1(3, "num_rows = %lu\n", png_ptr->num_rows);
+   png_debug1(3, "rowbytes = %lu,\n", png_ptr->rowbytes);
+   png_debug1(3, "irowbytes = %lu,\n", png_ptr->irowbytes);
+
+   png_ptr->flags |= PNG_FLAG_ROW_INIT;
+}
diff --git a/gs/libpng/pngset.c b/gs/libpng/pngset.c
new file mode 100644
index 000000000..5922cad0c
--- /dev/null
+++ b/gs/libpng/pngset.c
@@ -0,0 +1,1219 @@
+
+/* pngset.c - storage of image information into info struct
+ *
+ * libpng 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * The functions here are used during reads to store data from the file
+ * into the info struct, and during writes to store application data
+ * into the info struct for writing into the file.  This abstracts the
+ * info struct and allows us to change the structure in the future.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_bKGD_SUPPORTED)
+void PNGAPI
+png_set_bKGD(png_structp png_ptr, png_infop info_ptr, png_color_16p background)
+{
+   png_debug1(1, "in %s storage function\n", "bKGD");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   png_memcpy(&(info_ptr->background), background, png_sizeof(png_color_16));
+   info_ptr->valid |= PNG_INFO_bKGD;
+}
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_cHRM(png_structp png_ptr, png_infop info_ptr,
+   double white_x, double white_y, double red_x, double red_y,
+   double green_x, double green_y, double blue_x, double blue_y)
+{
+   png_debug1(1, "in %s storage function\n", "cHRM");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   if (white_x < 0.0 || white_y < 0.0 ||
+         red_x < 0.0 ||   red_y < 0.0 ||
+       green_x < 0.0 || green_y < 0.0 ||
+        blue_x < 0.0 ||  blue_y < 0.0)
+   {
+      png_warning(png_ptr,
+        "Ignoring attempt to set negative chromaticity value");
+      return;
+   }
+   if (white_x > 21474.83 || white_y > 21474.83 ||
+         red_x > 21474.83 ||   red_y > 21474.83 ||
+       green_x > 21474.83 || green_y > 21474.83 ||
+        blue_x > 21474.83 ||  blue_y > 21474.83)
+   {
+      png_warning(png_ptr,
+        "Ignoring attempt to set chromaticity value exceeding 21474.83");
+      return;
+   }
+
+   info_ptr->x_white = (float)white_x;
+   info_ptr->y_white = (float)white_y;
+   info_ptr->x_red   = (float)red_x;
+   info_ptr->y_red   = (float)red_y;
+   info_ptr->x_green = (float)green_x;
+   info_ptr->y_green = (float)green_y;
+   info_ptr->x_blue  = (float)blue_x;
+   info_ptr->y_blue  = (float)blue_y;
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   info_ptr->int_x_white = (png_fixed_point)(white_x*100000.+0.5);
+   info_ptr->int_y_white = (png_fixed_point)(white_y*100000.+0.5);
+   info_ptr->int_x_red   = (png_fixed_point)(  red_x*100000.+0.5);
+   info_ptr->int_y_red   = (png_fixed_point)(  red_y*100000.+0.5);
+   info_ptr->int_x_green = (png_fixed_point)(green_x*100000.+0.5);
+   info_ptr->int_y_green = (png_fixed_point)(green_y*100000.+0.5);
+   info_ptr->int_x_blue  = (png_fixed_point)( blue_x*100000.+0.5);
+   info_ptr->int_y_blue  = (png_fixed_point)( blue_y*100000.+0.5);
+#endif
+   info_ptr->valid |= PNG_INFO_cHRM;
+}
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void PNGAPI
+png_set_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,
+   png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
+   png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
+   png_fixed_point blue_x, png_fixed_point blue_y)
+{
+   png_debug1(1, "in %s storage function\n", "cHRM");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   if (white_x < 0 || white_y < 0 ||
+         red_x < 0 ||   red_y < 0 ||
+       green_x < 0 || green_y < 0 ||
+        blue_x < 0 ||  blue_y < 0)
+   {
+      png_warning(png_ptr,
+        "Ignoring attempt to set negative chromaticity value");
+      return;
+   }
+   if (white_x > (double) PNG_UINT_31_MAX ||
+       white_y > (double) PNG_UINT_31_MAX ||
+         red_x > (double) PNG_UINT_31_MAX ||
+         red_y > (double) PNG_UINT_31_MAX ||
+       green_x > (double) PNG_UINT_31_MAX ||
+       green_y > (double) PNG_UINT_31_MAX ||
+        blue_x > (double) PNG_UINT_31_MAX ||
+        blue_y > (double) PNG_UINT_31_MAX)
+   {
+      png_warning(png_ptr,
+        "Ignoring attempt to set chromaticity value exceeding 21474.83");
+      return;
+   }
+   info_ptr->int_x_white = white_x;
+   info_ptr->int_y_white = white_y;
+   info_ptr->int_x_red   = red_x;
+   info_ptr->int_y_red   = red_y;
+   info_ptr->int_x_green = green_x;
+   info_ptr->int_y_green = green_y;
+   info_ptr->int_x_blue  = blue_x;
+   info_ptr->int_y_blue  = blue_y;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   info_ptr->x_white = (float)(white_x/100000.);
+   info_ptr->y_white = (float)(white_y/100000.);
+   info_ptr->x_red   = (float)(  red_x/100000.);
+   info_ptr->y_red   = (float)(  red_y/100000.);
+   info_ptr->x_green = (float)(green_x/100000.);
+   info_ptr->y_green = (float)(green_y/100000.);
+   info_ptr->x_blue  = (float)( blue_x/100000.);
+   info_ptr->y_blue  = (float)( blue_y/100000.);
+#endif
+   info_ptr->valid |= PNG_INFO_cHRM;
+}
+#endif
+#endif
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_gAMA(png_structp png_ptr, png_infop info_ptr, double file_gamma)
+{
+   double gamma;
+   png_debug1(1, "in %s storage function\n", "gAMA");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   /* Check for overflow */
+   if (file_gamma > 21474.83)
+   {
+      png_warning(png_ptr, "Limiting gamma to 21474.83");
+      gamma=21474.83;
+   }
+   else
+      gamma=file_gamma;
+   info_ptr->gamma = (float)gamma;
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   info_ptr->int_gamma = (int)(gamma*100000.+.5);
+#endif
+   info_ptr->valid |= PNG_INFO_gAMA;
+   if(gamma == 0.0)
+      png_warning(png_ptr, "Setting gamma=0");
+}
+#endif
+void PNGAPI
+png_set_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, png_fixed_point
+   int_gamma)
+{
+   png_fixed_point gamma;
+
+   png_debug1(1, "in %s storage function\n", "gAMA");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   if (int_gamma > (png_fixed_point) PNG_UINT_31_MAX)
+   {
+     png_warning(png_ptr, "Limiting gamma to 21474.83");
+     gamma=PNG_UINT_31_MAX;
+   }
+   else
+   {
+     if (int_gamma < 0)
+     {
+       png_warning(png_ptr, "Setting negative gamma to zero");
+       gamma=0;
+     }
+     else
+       gamma=int_gamma;
+   }
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   info_ptr->gamma = (float)(gamma/100000.);
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   info_ptr->int_gamma = gamma;
+#endif
+   info_ptr->valid |= PNG_INFO_gAMA;
+   if(gamma == 0)
+      png_warning(png_ptr, "Setting gamma=0");
+}
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+void PNGAPI
+png_set_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p hist)
+{
+   int i;
+
+   png_debug1(1, "in %s storage function\n", "hIST");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+   if (info_ptr->num_palette == 0)
+   {
+       png_warning(png_ptr,
+          "Palette size 0, hIST allocation skipped.");
+       return;
+   }
+
+#ifdef PNG_FREE_ME_SUPPORTED
+   png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0);
+#endif
+   /* Changed from info->num_palette to 256 in version 1.2.1 */
+   png_ptr->hist = (png_uint_16p)png_malloc_warn(png_ptr,
+      (png_uint_32)(256 * png_sizeof (png_uint_16)));
+   if (png_ptr->hist == NULL)
+     {
+       png_warning(png_ptr, "Insufficient memory for hIST chunk data.");
+       return;
+     }
+
+   for (i = 0; i < info_ptr->num_palette; i++)
+       png_ptr->hist[i] = hist[i];
+   info_ptr->hist = png_ptr->hist;
+   info_ptr->valid |= PNG_INFO_hIST;
+
+#ifdef PNG_FREE_ME_SUPPORTED
+   info_ptr->free_me |= PNG_FREE_HIST;
+#else
+   png_ptr->flags |= PNG_FLAG_FREE_HIST;
+#endif
+}
+#endif
+
+void PNGAPI
+png_set_IHDR(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 width, png_uint_32 height, int bit_depth,
+   int color_type, int interlace_type, int compression_type,
+   int filter_type)
+{
+   png_debug1(1, "in %s storage function\n", "IHDR");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   /* check for width and height valid values */
+   if (width == 0 || height == 0)
+      png_error(png_ptr, "Image width or height is zero in IHDR");
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+   if (width > png_ptr->user_width_max || height > png_ptr->user_height_max)
+      png_error(png_ptr, "image size exceeds user limits in IHDR");
+#else
+   if (width > PNG_USER_WIDTH_MAX || height > PNG_USER_HEIGHT_MAX)
+      png_error(png_ptr, "image size exceeds user limits in IHDR");
+#endif
+   if (width > PNG_UINT_31_MAX || height > PNG_UINT_31_MAX)
+      png_error(png_ptr, "Invalid image size in IHDR");
+   if ( width > (PNG_UINT_32_MAX
+                 >> 3)      /* 8-byte RGBA pixels */
+                 - 64       /* bigrowbuf hack */
+                 - 1        /* filter byte */
+                 - 7*8      /* rounding of width to multiple of 8 pixels */
+                 - 8)       /* extra max_pixel_depth pad */
+      png_warning(png_ptr, "Width is too large for libpng to process pixels");
+
+   /* check other values */
+   if (bit_depth != 1 && bit_depth != 2 && bit_depth != 4 &&
+      bit_depth != 8 && bit_depth != 16)
+      png_error(png_ptr, "Invalid bit depth in IHDR");
+
+   if (color_type < 0 || color_type == 1 ||
+      color_type == 5 || color_type > 6)
+      png_error(png_ptr, "Invalid color type in IHDR");
+
+   if (((color_type == PNG_COLOR_TYPE_PALETTE) && bit_depth > 8) ||
+       ((color_type == PNG_COLOR_TYPE_RGB ||
+         color_type == PNG_COLOR_TYPE_GRAY_ALPHA ||
+         color_type == PNG_COLOR_TYPE_RGB_ALPHA) && bit_depth < 8))
+      png_error(png_ptr, "Invalid color type/bit depth combination in IHDR");
+
+   if (interlace_type >= PNG_INTERLACE_LAST)
+      png_error(png_ptr, "Unknown interlace method in IHDR");
+
+   if (compression_type != PNG_COMPRESSION_TYPE_BASE)
+      png_error(png_ptr, "Unknown compression method in IHDR");
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+   /* Accept filter_method 64 (intrapixel differencing) only if
+    * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
+    * 2. Libpng did not read a PNG signature (this filter_method is only
+    *    used in PNG datastreams that are embedded in MNG datastreams) and
+    * 3. The application called png_permit_mng_features with a mask that
+    *    included PNG_FLAG_MNG_FILTER_64 and
+    * 4. The filter_method is 64 and
+    * 5. The color_type is RGB or RGBA
+    */
+   if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&png_ptr->mng_features_permitted)
+      png_warning(png_ptr,"MNG features are not allowed in a PNG datastream\n");
+   if(filter_type != PNG_FILTER_TYPE_BASE)
+   {
+     if(!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+        (filter_type == PNG_INTRAPIXEL_DIFFERENCING) &&
+        ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
+        (color_type == PNG_COLOR_TYPE_RGB || 
+         color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
+        png_error(png_ptr, "Unknown filter method in IHDR");
+     if(png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)
+        png_warning(png_ptr, "Invalid filter method in IHDR");
+   }
+#else
+   if(filter_type != PNG_FILTER_TYPE_BASE)
+      png_error(png_ptr, "Unknown filter method in IHDR");
+#endif
+
+   info_ptr->width = width;
+   info_ptr->height = height;
+   info_ptr->bit_depth = (png_byte)bit_depth;
+   info_ptr->color_type =(png_byte) color_type;
+   info_ptr->compression_type = (png_byte)compression_type;
+   info_ptr->filter_type = (png_byte)filter_type;
+   info_ptr->interlace_type = (png_byte)interlace_type;
+   if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      info_ptr->channels = 1;
+   else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
+      info_ptr->channels = 3;
+   else
+      info_ptr->channels = 1;
+   if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
+      info_ptr->channels++;
+   info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
+
+   /* check for potential overflow */
+   if ( width > (PNG_UINT_32_MAX
+                 >> 3)      /* 8-byte RGBA pixels */
+                 - 64       /* bigrowbuf hack */
+                 - 1        /* filter byte */
+                 - 7*8      /* rounding of width to multiple of 8 pixels */
+                 - 8)       /* extra max_pixel_depth pad */
+      info_ptr->rowbytes = (png_size_t)0;
+   else
+      info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth,width);
+}
+
+#if defined(PNG_oFFs_SUPPORTED)
+void PNGAPI
+png_set_oFFs(png_structp png_ptr, png_infop info_ptr,
+   png_int_32 offset_x, png_int_32 offset_y, int unit_type)
+{
+   png_debug1(1, "in %s storage function\n", "oFFs");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->x_offset = offset_x;
+   info_ptr->y_offset = offset_y;
+   info_ptr->offset_unit_type = (png_byte)unit_type;
+   info_ptr->valid |= PNG_INFO_oFFs;
+}
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+void PNGAPI
+png_set_pCAL(png_structp png_ptr, png_infop info_ptr,
+   png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
+   png_charp units, png_charpp params)
+{
+   png_uint_32 length;
+   int i;
+
+   png_debug1(1, "in %s storage function\n", "pCAL");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   length = png_strlen(purpose) + 1;
+   png_debug1(3, "allocating purpose for info (%lu bytes)\n", length);
+   info_ptr->pcal_purpose = (png_charp)png_malloc_warn(png_ptr, length);
+   if (info_ptr->pcal_purpose == NULL)
+     {
+       png_warning(png_ptr, "Insufficient memory for pCAL purpose.");
+       return;
+     }
+   png_memcpy(info_ptr->pcal_purpose, purpose, (png_size_t)length);
+
+   png_debug(3, "storing X0, X1, type, and nparams in info\n");
+   info_ptr->pcal_X0 = X0;
+   info_ptr->pcal_X1 = X1;
+   info_ptr->pcal_type = (png_byte)type;
+   info_ptr->pcal_nparams = (png_byte)nparams;
+
+   length = png_strlen(units) + 1;
+   png_debug1(3, "allocating units for info (%lu bytes)\n", length);
+   info_ptr->pcal_units = (png_charp)png_malloc_warn(png_ptr, length);
+   if (info_ptr->pcal_units == NULL)
+     {
+       png_warning(png_ptr, "Insufficient memory for pCAL units.");
+       return;
+     }
+   png_memcpy(info_ptr->pcal_units, units, (png_size_t)length);
+
+   info_ptr->pcal_params = (png_charpp)png_malloc_warn(png_ptr,
+      (png_uint_32)((nparams + 1) * png_sizeof(png_charp)));
+   if (info_ptr->pcal_params == NULL)
+     {
+       png_warning(png_ptr, "Insufficient memory for pCAL params.");
+       return;
+     }
+
+   info_ptr->pcal_params[nparams] = NULL;
+
+   for (i = 0; i < nparams; i++)
+   {
+      length = png_strlen(params[i]) + 1;
+      png_debug2(3, "allocating parameter %d for info (%lu bytes)\n", i, length);
+      info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
+      if (info_ptr->pcal_params[i] == NULL)
+        {
+          png_warning(png_ptr, "Insufficient memory for pCAL parameter.");
+          return;
+        }
+      png_memcpy(info_ptr->pcal_params[i], params[i], (png_size_t)length);
+   }
+
+   info_ptr->valid |= PNG_INFO_pCAL;
+#ifdef PNG_FREE_ME_SUPPORTED
+   info_ptr->free_me |= PNG_FREE_PCAL;
+#endif
+}
+#endif
+
+#if defined(PNG_READ_sCAL_SUPPORTED) || defined(PNG_WRITE_sCAL_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_sCAL(png_structp png_ptr, png_infop info_ptr,
+             int unit, double width, double height)
+{
+   png_debug1(1, "in %s storage function\n", "sCAL");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->scal_unit = (png_byte)unit;
+   info_ptr->scal_pixel_width = width;
+   info_ptr->scal_pixel_height = height;
+
+   info_ptr->valid |= PNG_INFO_sCAL;
+}
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void PNGAPI
+png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr,
+             int unit, png_charp swidth, png_charp sheight)
+{
+   png_uint_32 length;
+
+   png_debug1(1, "in %s storage function\n", "sCAL");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->scal_unit = (png_byte)unit;
+
+   length = png_strlen(swidth) + 1;
+   png_debug1(3, "allocating unit for info (%d bytes)\n", length);
+   info_ptr->scal_s_width = (png_charp)png_malloc_warn(png_ptr, length);
+   if (info_ptr->scal_s_width == NULL)
+   {
+      png_warning(png_ptr, "Memory allocation failed while processing sCAL.");
+   }
+   png_memcpy(info_ptr->scal_s_width, swidth, (png_size_t)length);
+
+   length = png_strlen(sheight) + 1;
+   png_debug1(3, "allocating unit for info (%d bytes)\n", length);
+   info_ptr->scal_s_height = (png_charp)png_malloc_warn(png_ptr, length);
+   if (info_ptr->scal_s_height == NULL)
+   {
+      png_free (png_ptr, info_ptr->scal_s_width);
+      png_warning(png_ptr, "Memory allocation failed while processing sCAL.");
+   }
+   png_memcpy(info_ptr->scal_s_height, sheight, (png_size_t)length);
+
+   info_ptr->valid |= PNG_INFO_sCAL;
+#ifdef PNG_FREE_ME_SUPPORTED
+   info_ptr->free_me |= PNG_FREE_SCAL;
+#endif
+}
+#endif
+#endif
+#endif
+
+#if defined(PNG_pHYs_SUPPORTED)
+void PNGAPI
+png_set_pHYs(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 res_x, png_uint_32 res_y, int unit_type)
+{
+   png_debug1(1, "in %s storage function\n", "pHYs");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->x_pixels_per_unit = res_x;
+   info_ptr->y_pixels_per_unit = res_y;
+   info_ptr->phys_unit_type = (png_byte)unit_type;
+   info_ptr->valid |= PNG_INFO_pHYs;
+}
+#endif
+
+void PNGAPI
+png_set_PLTE(png_structp png_ptr, png_infop info_ptr,
+   png_colorp palette, int num_palette)
+{
+
+   png_debug1(1, "in %s storage function\n", "PLTE");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   /*
+    * It may not actually be necessary to set png_ptr->palette here;
+    * we do it for backward compatibility with the way the png_handle_tRNS
+    * function used to do the allocation.
+    */
+#ifdef PNG_FREE_ME_SUPPORTED
+   png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);
+#endif
+
+   /* Changed in libpng-1.2.1 to allocate 256 instead of num_palette entries,
+      in case of an invalid PNG file that has too-large sample values. */
+   png_ptr->palette = (png_colorp)png_malloc(png_ptr,
+      256 * png_sizeof(png_color));
+   png_memset(png_ptr->palette, 0, 256 * png_sizeof(png_color));
+   png_memcpy(png_ptr->palette, palette, num_palette * png_sizeof (png_color));
+   info_ptr->palette = png_ptr->palette;
+   info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
+
+#ifdef PNG_FREE_ME_SUPPORTED
+   info_ptr->free_me |= PNG_FREE_PLTE;
+#else
+   png_ptr->flags |= PNG_FLAG_FREE_PLTE;
+#endif
+
+   info_ptr->valid |= PNG_INFO_PLTE;
+}
+
+#if defined(PNG_sBIT_SUPPORTED)
+void PNGAPI
+png_set_sBIT(png_structp png_ptr, png_infop info_ptr,
+   png_color_8p sig_bit)
+{
+   png_debug1(1, "in %s storage function\n", "sBIT");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   png_memcpy(&(info_ptr->sig_bit), sig_bit, png_sizeof (png_color_8));
+   info_ptr->valid |= PNG_INFO_sBIT;
+}
+#endif
+
+#if defined(PNG_sRGB_SUPPORTED)
+void PNGAPI
+png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int intent)
+{
+   png_debug1(1, "in %s storage function\n", "sRGB");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->srgb_intent = (png_byte)intent;
+   info_ptr->valid |= PNG_INFO_sRGB;
+}
+
+void PNGAPI
+png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
+   int intent)
+{
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   float file_gamma;
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   png_fixed_point int_file_gamma;
+#endif
+#endif
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   png_fixed_point int_white_x, int_white_y, int_red_x, int_red_y, int_green_x,
+      int_green_y, int_blue_x, int_blue_y;
+#endif
+#endif
+   png_debug1(1, "in %s storage function\n", "sRGB_gAMA_and_cHRM");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   png_set_sRGB(png_ptr, info_ptr, intent);
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   file_gamma = (float).45455;
+   png_set_gAMA(png_ptr, info_ptr, file_gamma);
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   int_file_gamma = 45455L;
+   png_set_gAMA_fixed(png_ptr, info_ptr, int_file_gamma);
+#endif
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   int_white_x = 31270L;
+   int_white_y = 32900L;
+   int_red_x   = 64000L;
+   int_red_y   = 33000L;
+   int_green_x = 30000L;
+   int_green_y = 60000L;
+   int_blue_x  = 15000L;
+   int_blue_y  =  6000L;
+
+   png_set_cHRM_fixed(png_ptr, info_ptr,
+      int_white_x, int_white_y, int_red_x, int_red_y, int_green_x, int_green_y,
+      int_blue_x, int_blue_y);
+#endif
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   white_x = (float).3127;
+   white_y = (float).3290;
+   red_x   = (float).64;
+   red_y   = (float).33;
+   green_x = (float).30;
+   green_y = (float).60;
+   blue_x  = (float).15;
+   blue_y  = (float).06;
+
+   png_set_cHRM(png_ptr, info_ptr,
+      white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);
+#endif
+#endif
+}
+#endif
+
+
+#if defined(PNG_iCCP_SUPPORTED)
+void PNGAPI
+png_set_iCCP(png_structp png_ptr, png_infop info_ptr,
+             png_charp name, int compression_type,
+             png_charp profile, png_uint_32 proflen)
+{
+   png_charp new_iccp_name;
+   png_charp new_iccp_profile;
+
+   png_debug1(1, "in %s storage function\n", "iCCP");
+   if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
+      return;
+
+   new_iccp_name = (png_charp)png_malloc_warn(png_ptr, png_strlen(name)+1);
+   if (new_iccp_name == NULL)
+   {
+      png_warning(png_ptr, "Insufficient memory to process iCCP chunk.");
+      return;
+   }
+   png_strcpy(new_iccp_name, name);
+   new_iccp_profile = (png_charp)png_malloc_warn(png_ptr, proflen);
+   if (new_iccp_profile == NULL)
+   {
+      png_free (png_ptr, new_iccp_name);
+      png_warning(png_ptr, "Insufficient memory to process iCCP profile.");
+      return;
+   }
+   png_memcpy(new_iccp_profile, profile, (png_size_t)proflen);
+
+   png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);
+
+   info_ptr->iccp_proflen = proflen;
+   info_ptr->iccp_name = new_iccp_name;
+   info_ptr->iccp_profile = new_iccp_profile;
+   /* Compression is always zero but is here so the API and info structure
+    * does not have to change if we introduce multiple compression types */
+   info_ptr->iccp_compression = (png_byte)compression_type;
+#ifdef PNG_FREE_ME_SUPPORTED
+   info_ptr->free_me |= PNG_FREE_ICCP;
+#endif
+   info_ptr->valid |= PNG_INFO_iCCP;
+}
+#endif
+
+#if defined(PNG_TEXT_SUPPORTED)
+void PNGAPI
+png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
+   int num_text)
+{
+   int ret;
+   ret=png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
+   if (ret)
+     png_error(png_ptr, "Insufficient memory to store text");
+}
+
+int /* PRIVATE */
+png_set_text_2(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
+   int num_text)
+{
+   int i;
+
+   png_debug1(1, "in %s storage function\n", (png_ptr->chunk_name[0] == '\0' ?
+      "text" : (png_const_charp)png_ptr->chunk_name));
+
+   if (png_ptr == NULL || info_ptr == NULL || num_text == 0)
+      return(0);
+
+   /* Make sure we have enough space in the "text" array in info_struct
+    * to hold all of the incoming text_ptr objects.
+    */
+   if (info_ptr->num_text + num_text > info_ptr->max_text)
+   {
+      if (info_ptr->text != NULL)
+      {
+         png_textp old_text;
+         int old_max;
+
+         old_max = info_ptr->max_text;
+         info_ptr->max_text = info_ptr->num_text + num_text + 8;
+         old_text = info_ptr->text;
+         info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
+            (png_uint_32)(info_ptr->max_text * png_sizeof (png_text)));
+         if (info_ptr->text == NULL)
+           {
+             png_free(png_ptr, old_text);
+             return(1);
+           }
+         png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max *
+            png_sizeof(png_text)));
+         png_free(png_ptr, old_text);
+      }
+      else
+      {
+         info_ptr->max_text = num_text + 8;
+         info_ptr->num_text = 0;
+         info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
+            (png_uint_32)(info_ptr->max_text * png_sizeof (png_text)));
+         if (info_ptr->text == NULL)
+           return(1);
+#ifdef PNG_FREE_ME_SUPPORTED
+         info_ptr->free_me |= PNG_FREE_TEXT;
+#endif
+      }
+      png_debug1(3, "allocated %d entries for info_ptr->text\n",
+         info_ptr->max_text);
+   }
+   for (i = 0; i < num_text; i++)
+   {
+      png_size_t text_length,key_len;
+      png_size_t lang_len,lang_key_len;
+      png_textp textp = &(info_ptr->text[info_ptr->num_text]);
+
+      if (text_ptr[i].key == NULL)
+          continue;
+
+      key_len = png_strlen(text_ptr[i].key);
+
+      if(text_ptr[i].compression <= 0)
+      {
+        lang_len = 0;
+        lang_key_len = 0;
+      }
+      else
+#ifdef PNG_iTXt_SUPPORTED
+      {
+        /* set iTXt data */
+        if (text_ptr[i].lang != NULL)
+          lang_len = png_strlen(text_ptr[i].lang);
+        else
+          lang_len = 0;
+        if (text_ptr[i].lang_key != NULL)
+          lang_key_len = png_strlen(text_ptr[i].lang_key);
+        else
+          lang_key_len = 0;
+      }
+#else
+      {
+        png_warning(png_ptr, "iTXt chunk not supported.");
+        continue;
+      }
+#endif
+
+      if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0')
+      {
+         text_length = 0;
+#ifdef PNG_iTXt_SUPPORTED
+         if(text_ptr[i].compression > 0)
+            textp->compression = PNG_ITXT_COMPRESSION_NONE;
+         else
+#endif
+            textp->compression = PNG_TEXT_COMPRESSION_NONE;
+      }
+      else
+      {
+         text_length = png_strlen(text_ptr[i].text);
+         textp->compression = text_ptr[i].compression;
+      }
+
+      textp->key = (png_charp)png_malloc_warn(png_ptr,
+         (png_uint_32)(key_len + text_length + lang_len + lang_key_len + 4));
+      if (textp->key == NULL)
+        return(1);
+      png_debug2(2, "Allocated %lu bytes at %x in png_set_text\n",
+         (png_uint_32)(key_len + lang_len + lang_key_len + text_length + 4),
+         (int)textp->key);
+
+      png_memcpy(textp->key, text_ptr[i].key,
+         (png_size_t)(key_len));
+      *(textp->key+key_len) = '\0';
+#ifdef PNG_iTXt_SUPPORTED
+      if (text_ptr[i].compression > 0)
+      {
+         textp->lang=textp->key + key_len + 1;
+         png_memcpy(textp->lang, text_ptr[i].lang, lang_len);
+         *(textp->lang+lang_len) = '\0';
+         textp->lang_key=textp->lang + lang_len + 1;
+         png_memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
+         *(textp->lang_key+lang_key_len) = '\0';
+         textp->text=textp->lang_key + lang_key_len + 1;
+      }
+      else
+#endif
+      {
+#ifdef PNG_iTXt_SUPPORTED
+         textp->lang=NULL;
+         textp->lang_key=NULL;
+#endif
+         textp->text=textp->key + key_len + 1;
+      }
+      if(text_length)
+         png_memcpy(textp->text, text_ptr[i].text,
+            (png_size_t)(text_length));
+      *(textp->text+text_length) = '\0';
+
+#ifdef PNG_iTXt_SUPPORTED
+      if(textp->compression > 0)
+      {
+         textp->text_length = 0;
+         textp->itxt_length = text_length;
+      }
+      else
+#endif
+      {
+         textp->text_length = text_length;
+#ifdef PNG_iTXt_SUPPORTED
+         textp->itxt_length = 0;
+#endif
+      }
+      info_ptr->text[info_ptr->num_text]= *textp;
+      info_ptr->num_text++;
+      png_debug1(3, "transferred text chunk %d\n", info_ptr->num_text);
+   }
+   return(0);
+}
+#endif
+
+#if defined(PNG_tIME_SUPPORTED)
+void PNGAPI
+png_set_tIME(png_structp png_ptr, png_infop info_ptr, png_timep mod_time)
+{
+   png_debug1(1, "in %s storage function\n", "tIME");
+   if (png_ptr == NULL || info_ptr == NULL ||
+       (png_ptr->mode & PNG_WROTE_tIME))
+      return;
+
+   png_memcpy(&(info_ptr->mod_time), mod_time, png_sizeof (png_time));
+   info_ptr->valid |= PNG_INFO_tIME;
+}
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+void PNGAPI
+png_set_tRNS(png_structp png_ptr, png_infop info_ptr,
+   png_bytep trans, int num_trans, png_color_16p trans_values)
+{
+   png_debug1(1, "in %s storage function\n", "tRNS");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   if (trans != NULL)
+   {
+       /*
+        * It may not actually be necessary to set png_ptr->trans here;
+        * we do it for backward compatibility with the way the png_handle_tRNS
+        * function used to do the allocation.
+        */
+#ifdef PNG_FREE_ME_SUPPORTED
+       png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
+#endif
+       /* Changed from num_trans to 256 in version 1.2.1 */
+       png_ptr->trans = info_ptr->trans = (png_bytep)png_malloc(png_ptr,
+           (png_uint_32)256);
+       png_memcpy(info_ptr->trans, trans, (png_size_t)num_trans);
+#ifdef PNG_FREE_ME_SUPPORTED
+       info_ptr->free_me |= PNG_FREE_TRNS;
+#else
+       png_ptr->flags |= PNG_FLAG_FREE_TRNS;
+#endif
+   }
+
+   if (trans_values != NULL)
+   {
+      png_memcpy(&(info_ptr->trans_values), trans_values,
+         png_sizeof(png_color_16));
+      if (num_trans == 0)
+        num_trans = 1;
+   }
+   info_ptr->num_trans = (png_uint_16)num_trans;
+   info_ptr->valid |= PNG_INFO_tRNS;
+}
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+void PNGAPI
+png_set_sPLT(png_structp png_ptr,
+             png_infop info_ptr, png_sPLT_tp entries, int nentries)
+{
+    png_sPLT_tp np;
+    int i;
+
+    np = (png_sPLT_tp)png_malloc_warn(png_ptr,
+        (info_ptr->splt_palettes_num + nentries) * png_sizeof(png_sPLT_t));
+    if (np == NULL)
+    {
+      png_warning(png_ptr, "No memory for sPLT palettes.");
+      return;
+    }
+
+    png_memcpy(np, info_ptr->splt_palettes,
+           info_ptr->splt_palettes_num * png_sizeof(png_sPLT_t));
+    png_free(png_ptr, info_ptr->splt_palettes);
+    info_ptr->splt_palettes=NULL;
+
+    for (i = 0; i < nentries; i++)
+    {
+        png_sPLT_tp to = np + info_ptr->splt_palettes_num + i;
+        png_sPLT_tp from = entries + i;
+
+        to->name = (png_charp)png_malloc(png_ptr,
+            png_strlen(from->name) + 1);
+        /* TODO: use png_malloc_warn */
+        png_strcpy(to->name, from->name);
+        to->entries = (png_sPLT_entryp)png_malloc(png_ptr,
+            from->nentries * png_sizeof(png_sPLT_t));
+        /* TODO: use png_malloc_warn */
+        png_memcpy(to->entries, from->entries,
+            from->nentries * png_sizeof(png_sPLT_t));
+        to->nentries = from->nentries;
+        to->depth = from->depth;
+    }
+
+    info_ptr->splt_palettes = np;
+    info_ptr->splt_palettes_num += nentries;
+    info_ptr->valid |= PNG_INFO_sPLT;
+#ifdef PNG_FREE_ME_SUPPORTED
+    info_ptr->free_me |= PNG_FREE_SPLT;
+#endif
+}
+#endif /* PNG_sPLT_SUPPORTED */
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+void PNGAPI
+png_set_unknown_chunks(png_structp png_ptr,
+   png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns)
+{
+    png_unknown_chunkp np;
+    int i;
+
+    if (png_ptr == NULL || info_ptr == NULL || num_unknowns == 0)
+        return;
+
+    np = (png_unknown_chunkp)png_malloc_warn(png_ptr,
+        (info_ptr->unknown_chunks_num + num_unknowns) *
+        png_sizeof(png_unknown_chunk));
+    if (np == NULL)
+    {
+       png_warning(png_ptr, "Out of memory while processing unknown chunk.");
+       return;
+    }
+
+    png_memcpy(np, info_ptr->unknown_chunks,
+           info_ptr->unknown_chunks_num * png_sizeof(png_unknown_chunk));
+    png_free(png_ptr, info_ptr->unknown_chunks);
+    info_ptr->unknown_chunks=NULL;
+
+    for (i = 0; i < num_unknowns; i++)
+    {
+        png_unknown_chunkp to = np + info_ptr->unknown_chunks_num + i;
+        png_unknown_chunkp from = unknowns + i;
+
+        png_strncpy((png_charp)to->name, (png_charp)from->name, 5);
+        to->data = (png_bytep)png_malloc_warn(png_ptr, from->size);
+        if (to->data == NULL)
+        {
+           png_warning(png_ptr, "Out of memory processing unknown chunk.");
+        }
+        else
+        {
+           png_memcpy(to->data, from->data, from->size);
+           to->size = from->size;
+
+           /* note our location in the read or write sequence */
+           to->location = (png_byte)(png_ptr->mode & 0xff);
+        }
+    }
+
+    info_ptr->unknown_chunks = np;
+    info_ptr->unknown_chunks_num += num_unknowns;
+#ifdef PNG_FREE_ME_SUPPORTED
+    info_ptr->free_me |= PNG_FREE_UNKN;
+#endif
+}
+void PNGAPI
+png_set_unknown_chunk_location(png_structp png_ptr, png_infop info_ptr,
+   int chunk, int location)
+{
+   if(png_ptr != NULL && info_ptr != NULL && chunk >= 0 && chunk <
+         (int)info_ptr->unknown_chunks_num)
+      info_ptr->unknown_chunks[chunk].location = (png_byte)location;
+}
+#endif
+
+#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
+    defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
+void PNGAPI
+png_permit_empty_plte (png_structp png_ptr, int empty_plte_permitted)
+{
+   /* This function is deprecated in favor of png_permit_mng_features()
+      and will be removed from libpng-2.0.0 */
+   png_debug(1, "in png_permit_empty_plte, DEPRECATED.\n");
+   if (png_ptr == NULL)
+      return;
+   png_ptr->mng_features_permitted = (png_byte)
+     ((png_ptr->mng_features_permitted & (~(PNG_FLAG_MNG_EMPTY_PLTE))) |
+     ((empty_plte_permitted & PNG_FLAG_MNG_EMPTY_PLTE)));
+}
+#endif
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+png_uint_32 PNGAPI
+png_permit_mng_features (png_structp png_ptr, png_uint_32 mng_features)
+{
+   png_debug(1, "in png_permit_mng_features\n");
+   if (png_ptr == NULL)
+      return (png_uint_32)0;
+   png_ptr->mng_features_permitted =
+     (png_byte)(mng_features & PNG_ALL_MNG_FEATURES);
+   return (png_uint_32)png_ptr->mng_features_permitted;
+}
+#endif
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+void PNGAPI
+png_set_keep_unknown_chunks(png_structp png_ptr, int keep, png_bytep
+   chunk_list, int num_chunks)
+{
+    png_bytep new_list, p;
+    int i, old_num_chunks;
+    if (num_chunks == 0)
+    {
+      if(keep == PNG_HANDLE_CHUNK_ALWAYS || keep == PNG_HANDLE_CHUNK_IF_SAFE)
+        png_ptr->flags |= PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
+      else
+        png_ptr->flags &= ~PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
+
+      if(keep == PNG_HANDLE_CHUNK_ALWAYS)
+        png_ptr->flags |= PNG_FLAG_KEEP_UNSAFE_CHUNKS;
+      else
+        png_ptr->flags &= ~PNG_FLAG_KEEP_UNSAFE_CHUNKS;
+      return;
+    }
+    if (chunk_list == NULL)
+      return;
+    old_num_chunks=png_ptr->num_chunk_list;
+    new_list=(png_bytep)png_malloc(png_ptr,
+       (png_uint_32)(5*(num_chunks+old_num_chunks)));
+    if(png_ptr->chunk_list != NULL)
+    {
+       png_memcpy(new_list, png_ptr->chunk_list,
+          (png_size_t)(5*old_num_chunks));
+       png_free(png_ptr, png_ptr->chunk_list);
+       png_ptr->chunk_list=NULL;
+    }
+    png_memcpy(new_list+5*old_num_chunks, chunk_list,
+       (png_size_t)(5*num_chunks));
+    for (p=new_list+5*old_num_chunks+4, i=0; i<num_chunks; i++, p+=5)
+       *p=(png_byte)keep;
+    png_ptr->num_chunk_list=old_num_chunks+num_chunks;
+    png_ptr->chunk_list=new_list;
+#ifdef PNG_FREE_ME_SUPPORTED
+    png_ptr->free_me |= PNG_FREE_LIST;
+#endif
+}
+#endif
+
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+void PNGAPI
+png_set_read_user_chunk_fn(png_structp png_ptr, png_voidp user_chunk_ptr,
+   png_user_chunk_ptr read_user_chunk_fn)
+{
+   png_debug(1, "in png_set_read_user_chunk_fn\n");
+   png_ptr->read_user_chunk_fn = read_user_chunk_fn;
+   png_ptr->user_chunk_ptr = user_chunk_ptr;
+}
+#endif
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+void PNGAPI
+png_set_rows(png_structp png_ptr, png_infop info_ptr, png_bytepp row_pointers)
+{
+   png_debug1(1, "in %s storage function\n", "rows");
+
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   if(info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
+      png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
+   info_ptr->row_pointers = row_pointers;
+   if(row_pointers)
+      info_ptr->valid |= PNG_INFO_IDAT;
+}
+#endif
+
+#ifdef PNG_WRITE_SUPPORTED
+void PNGAPI
+png_set_compression_buffer_size(png_structp png_ptr, png_uint_32 size)
+{
+    if(png_ptr->zbuf)
+       png_free(png_ptr, png_ptr->zbuf);
+    png_ptr->zbuf_size = (png_size_t)size;
+    png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, size);
+    png_ptr->zstream.next_out = png_ptr->zbuf;
+    png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+}
+#endif
+
+void PNGAPI
+png_set_invalid(png_structp png_ptr, png_infop info_ptr, int mask)
+{
+   if (png_ptr && info_ptr)
+      info_ptr->valid &= ~(mask);
+}
+
+
+#ifndef PNG_1_0_X
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+/* this function was added to libpng 1.2.0 and should always exist by default */
+void PNGAPI
+png_set_asm_flags (png_structp png_ptr, png_uint_32 asm_flags)
+{
+    png_uint_32 settable_asm_flags;
+    png_uint_32 settable_mmx_flags;
+
+    settable_mmx_flags =
+#ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
+                         PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  |
+#endif
+#ifdef PNG_HAVE_ASSEMBLER_READ_INTERLACE
+                         PNG_ASM_FLAG_MMX_READ_INTERLACE    |
+#endif
+#ifdef PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+                         PNG_ASM_FLAG_MMX_READ_FILTER_SUB   |
+                         PNG_ASM_FLAG_MMX_READ_FILTER_UP    |
+                         PNG_ASM_FLAG_MMX_READ_FILTER_AVG   |
+                         PNG_ASM_FLAG_MMX_READ_FILTER_PAETH |
+#endif
+                         0;
+
+    /* could be some non-MMX ones in the future, but not currently: */
+    settable_asm_flags = settable_mmx_flags;
+
+    if (!(png_ptr->asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_COMPILED) ||
+        !(png_ptr->asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU))
+    {
+        /* clear all MMX flags if MMX isn't supported */
+        settable_asm_flags &= ~settable_mmx_flags;
+        png_ptr->asm_flags &= ~settable_mmx_flags;
+    }
+
+    /* we're replacing the settable bits with those passed in by the user,
+     * so first zero them out of the master copy, then logical-OR in the
+     * allowed subset that was requested */
+
+    png_ptr->asm_flags &= ~settable_asm_flags;               /* zero them */
+    png_ptr->asm_flags |= (asm_flags & settable_asm_flags);  /* set them */
+}
+#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
+
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+/* this function was added to libpng 1.2.0 */
+void PNGAPI
+png_set_mmx_thresholds (png_structp png_ptr,
+                        png_byte mmx_bitdepth_threshold,
+                        png_uint_32 mmx_rowbytes_threshold)
+{
+    png_ptr->mmx_bitdepth_threshold = mmx_bitdepth_threshold;
+    png_ptr->mmx_rowbytes_threshold = mmx_rowbytes_threshold;
+}
+#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
+
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+/* this function was added to libpng 1.2.6 */
+void PNGAPI
+png_set_user_limits (png_structp png_ptr, png_uint_32 user_width_max,
+    png_uint_32 user_height_max)
+{
+    /* Images with dimensions larger than these limits will be
+     * rejected by png_set_IHDR().  To accept any PNG datastream
+     * regardless of dimensions, set both limits to 0x7ffffffL.
+     */
+    png_ptr->user_width_max = user_width_max;
+    png_ptr->user_height_max = user_height_max;
+}
+#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
+
+#endif /* ?PNG_1_0_X */
diff --git a/gs/libpng/pngtest.c b/gs/libpng/pngtest.c
new file mode 100644
index 000000000..f2085e1e5
--- /dev/null
+++ b/gs/libpng/pngtest.c
@@ -0,0 +1,1554 @@
+
+/* pngtest.c - a simple test program to test libpng
+ *
+ * libpng 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This program reads in a PNG image, writes it out again, and then
+ * compares the two files.  If the files are identical, this shows that
+ * the basic chunk handling, filtering, and (de)compression code is working
+ * properly.  It does not currently test all of the transforms, although
+ * it probably should.
+ *
+ * The program will report "FAIL" in certain legitimate cases:
+ * 1) when the compression level or filter selection method is changed.
+ * 2) when the maximum IDAT size (PNG_ZBUF_SIZE in pngconf.h) is not 8192.
+ * 3) unknown unsafe-to-copy ancillary chunks or unknown critical chunks
+ *    exist in the input file.
+ * 4) others not listed here...
+ * In these cases, it is best to check with another tool such as "pngcheck"
+ * to see what the differences between the two files are.
+ *
+ * If a filename is given on the command-line, then this file is used
+ * for the input, rather than the default "pngtest.png".  This allows
+ * testing a wide variety of files easily.  You can also test a number
+ * of files at once by typing "pngtest -m file1.png file2.png ..."
+ */
+
+#include "png.h"
+
+#if defined(_WIN32_WCE)
+#  if _WIN32_WCE < 211
+     __error__ (f|w)printf functions are not supported on old WindowsCE.;
+#  endif
+#  include <windows.h>
+#  include <stdlib.h>
+#  define READFILE(file, data, length, check) \
+     if (ReadFile(file, data, length, &check,NULL)) check = 0
+#  define WRITEFILE(file, data, length, check)) \
+     if (WriteFile(file, data, length, &check, NULL)) check = 0
+#  define FCLOSE(file) CloseHandle(file)
+#else
+#  include <stdio.h>
+#  include <stdlib.h>
+#  include <assert.h>
+#  define READFILE(file, data, length, check) \
+     check=(png_size_t)fread(data,(png_size_t)1,length,file)
+#  define WRITEFILE(file, data, length, check) \
+     check=(png_size_t)fwrite(data,(png_size_t)1, length, file)
+#  define FCLOSE(file) fclose(file)
+#endif
+
+#if defined(PNG_NO_STDIO)
+#  if defined(_WIN32_WCE)
+     typedef HANDLE                png_FILE_p;
+#  else
+     typedef FILE                * png_FILE_p;
+#  endif
+#endif
+
+/* Makes pngtest verbose so we can find problems (needs to be before png.h) */
+#ifndef PNG_DEBUG
+#  define PNG_DEBUG 0
+#endif
+
+#if !PNG_DEBUG
+#  define SINGLE_ROWBUF_ALLOC  /* makes buffer overruns easier to nail */
+#endif
+
+/* Turn on CPU timing
+#define PNGTEST_TIMING
+*/
+
+#ifdef PNG_NO_FLOATING_POINT_SUPPORTED
+#undef PNGTEST_TIMING
+#endif
+
+#ifdef PNGTEST_TIMING
+static float t_start, t_stop, t_decode, t_encode, t_misc;
+#include <time.h>
+#endif
+
+/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
+#ifndef png_jmpbuf
+#  define png_jmpbuf(png_ptr) png_ptr->jmpbuf
+#endif
+
+#ifdef PNGTEST_TIMING
+static float t_start, t_stop, t_decode, t_encode, t_misc;
+#if !defined(PNG_tIME_SUPPORTED)
+#include <time.h>
+#endif
+#endif
+
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+static int tIME_chunk_present=0;
+static char tIME_string[30] = "no tIME chunk present in file";
+#endif
+
+static int verbose = 0;
+
+int test_one_file PNGARG((PNG_CONST char *inname, PNG_CONST char *outname));
+
+#ifdef __TURBOC__
+#include <mem.h>
+#endif
+
+/* defined so I can write to a file on gui/windowing platforms */
+/*  #define STDERR stderr  */
+#define STDERR stdout   /* for DOS */
+
+/* example of using row callbacks to make a simple progress meter */
+static int status_pass=1;
+static int status_dots_requested=0;
+static int status_dots=1;
+
+void
+#ifdef PNG_1_0_X
+PNGAPI
+#endif
+read_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass);
+void
+#ifdef PNG_1_0_X
+PNGAPI
+#endif
+read_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass)
+{
+    if(png_ptr == NULL || row_number > PNG_UINT_31_MAX) return;
+    if(status_pass != pass)
+    {
+       fprintf(stdout,"\n Pass %d: ",pass);
+       status_pass = pass;
+       status_dots = 31;
+    }
+    status_dots--;
+    if(status_dots == 0)
+    {
+       fprintf(stdout, "\n         ");
+       status_dots=30;
+    }
+    fprintf(stdout, "r");
+}
+
+void
+#ifdef PNG_1_0_X
+PNGAPI
+#endif
+write_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass);
+void
+#ifdef PNG_1_0_X
+PNGAPI
+#endif
+write_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass)
+{
+    if(png_ptr == NULL || row_number > PNG_UINT_31_MAX || pass > 7) return;
+    fprintf(stdout, "w");
+}
+
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+/* Example of using user transform callback (we don't transform anything,
+   but merely examine the row filters.  We set this to 256 rather than
+   5 in case illegal filter values are present.) */
+static png_uint_32 filters_used[256];
+void
+#ifdef PNG_1_0_X
+PNGAPI
+#endif
+count_filters(png_structp png_ptr, png_row_infop row_info, png_bytep data);
+void
+#ifdef PNG_1_0_X
+PNGAPI
+#endif
+count_filters(png_structp png_ptr, png_row_infop row_info, png_bytep data)
+{
+    if(png_ptr != NULL && row_info != NULL)
+      ++filters_used[*(data-1)];
+}
+#endif
+
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+/* example of using user transform callback (we don't transform anything,
+   but merely count the zero samples) */
+
+static png_uint_32 zero_samples;
+
+void
+#ifdef PNG_1_0_X
+PNGAPI
+#endif
+count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data);
+void
+#ifdef PNG_1_0_X
+PNGAPI
+#endif
+count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data)
+{
+   png_bytep dp = data;
+   if(png_ptr == NULL)return;
+
+   /* contents of row_info:
+    *  png_uint_32 width      width of row
+    *  png_uint_32 rowbytes   number of bytes in row
+    *  png_byte color_type    color type of pixels
+    *  png_byte bit_depth     bit depth of samples
+    *  png_byte channels      number of channels (1-4)
+    *  png_byte pixel_depth   bits per pixel (depth*channels)
+    */
+
+
+    /* counts the number of zero samples (or zero pixels if color_type is 3 */
+
+    if(row_info->color_type == 0 || row_info->color_type == 3)
+    {
+       int pos=0;
+       png_uint_32 n, nstop;
+       for (n=0, nstop=row_info->width; n<nstop; n++)
+       {
+          if(row_info->bit_depth == 1)
+          {
+             if(((*dp << pos++ ) & 0x80) == 0) zero_samples++;
+             if(pos == 8)
+             {
+                pos = 0;
+                dp++;
+             }
+          }
+          if(row_info->bit_depth == 2)
+          {
+             if(((*dp << (pos+=2)) & 0xc0) == 0) zero_samples++;
+             if(pos == 8)
+             {
+                pos = 0;
+                dp++;
+             }
+          }
+          if(row_info->bit_depth == 4)
+          {
+             if(((*dp << (pos+=4)) & 0xf0) == 0) zero_samples++;
+             if(pos == 8)
+             {
+                pos = 0;
+                dp++;
+             }
+          }
+          if(row_info->bit_depth == 8)
+             if(*dp++ == 0) zero_samples++;
+          if(row_info->bit_depth == 16)
+          {
+             if((*dp | *(dp+1)) == 0) zero_samples++;
+             dp+=2;
+          }
+       }
+    }
+    else /* other color types */
+    {
+       png_uint_32 n, nstop;
+       int channel;
+       int color_channels = row_info->channels;
+       if(row_info->color_type > 3)color_channels--;
+
+       for (n=0, nstop=row_info->width; n<nstop; n++)
+       {
+          for (channel = 0; channel < color_channels; channel++)
+          {
+             if(row_info->bit_depth == 8)
+                if(*dp++ == 0) zero_samples++;
+             if(row_info->bit_depth == 16)
+             {
+                if((*dp | *(dp+1)) == 0) zero_samples++;
+                dp+=2;
+             }
+          }
+          if(row_info->color_type > 3)
+          {
+             dp++;
+             if(row_info->bit_depth == 16)dp++;
+          }
+       }
+    }
+}
+#endif /* PNG_WRITE_USER_TRANSFORM_SUPPORTED */
+
+static int wrote_question = 0;
+
+#if defined(PNG_NO_STDIO)
+/* START of code to validate stdio-free compilation */
+/* These copies of the default read/write functions come from pngrio.c and */
+/* pngwio.c.  They allow "don't include stdio" testing of the library. */
+/* This is the function that does the actual reading of data.  If you are
+   not reading from a standard C stream, you should create a replacement
+   read_data function and use it at run time with png_set_read_fn(), rather
+   than changing the library. */
+
+#ifndef USE_FAR_KEYWORD
+static void
+pngtest_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   png_size_t check;
+
+   /* fread() returns 0 on error, so it is OK to store this in a png_size_t
+    * instead of an int, which is what fread() actually returns.
+    */
+   READFILE((png_FILE_p)png_ptr->io_ptr, data, length, check);
+
+   if (check != length)
+   {
+      png_error(png_ptr, "Read Error!");
+   }
+}
+#else
+/* this is the model-independent version. Since the standard I/O library
+   can't handle far buffers in the medium and small models, we have to copy
+   the data.
+*/
+
+#define NEAR_BUF_SIZE 1024
+#define MIN(a,b) (a <= b ? a : b)
+
+static void
+pngtest_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   int check;
+   png_byte *n_data;
+   png_FILE_p io_ptr;
+
+   /* Check if data really is near. If so, use usual code. */
+   n_data = (png_byte *)CVT_PTR_NOCHECK(data);
+   io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr);
+   if ((png_bytep)n_data == data)
+   {
+      READFILE(io_ptr, n_data, length, check);
+   }
+   else
+   {
+      png_byte buf[NEAR_BUF_SIZE];
+      png_size_t read, remaining, err;
+      check = 0;
+      remaining = length;
+      do
+      {
+         read = MIN(NEAR_BUF_SIZE, remaining);
+         READFILE(io_ptr, buf, 1, err);
+         png_memcpy(data, buf, read); /* copy far buffer to near buffer */
+         if(err != read)
+            break;
+         else
+            check += err;
+         data += read;
+         remaining -= read;
+      }
+      while (remaining != 0);
+   }
+   if (check != length)
+   {
+      png_error(png_ptr, "read Error");
+   }
+}
+#endif /* USE_FAR_KEYWORD */
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+static void
+pngtest_flush(png_structp png_ptr)
+{
+#if !defined(_WIN32_WCE)
+   png_FILE_p io_ptr;
+   io_ptr = (png_FILE_p)CVT_PTR((png_ptr->io_ptr));
+   if (io_ptr != NULL)
+      fflush(io_ptr);
+#endif
+}
+#endif
+
+/* This is the function that does the actual writing of data.  If you are
+   not writing to a standard C stream, you should create a replacement
+   write_data function and use it at run time with png_set_write_fn(), rather
+   than changing the library. */
+#ifndef USE_FAR_KEYWORD
+static void
+pngtest_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   png_uint_32 check;
+
+   WRITEFILE((png_FILE_p)png_ptr->io_ptr,  data, length, check);
+   if (check != length)
+   {
+      png_error(png_ptr, "Write Error");
+   }
+}
+#else
+/* this is the model-independent version. Since the standard I/O library
+   can't handle far buffers in the medium and small models, we have to copy
+   the data.
+*/
+
+#define NEAR_BUF_SIZE 1024
+#define MIN(a,b) (a <= b ? a : b)
+
+static void
+pngtest_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   png_uint_32 check;
+   png_byte *near_data;  /* Needs to be "png_byte *" instead of "png_bytep" */
+   png_FILE_p io_ptr;
+
+   /* Check if data really is near. If so, use usual code. */
+   near_data = (png_byte *)CVT_PTR_NOCHECK(data);
+   io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr);
+   if ((png_bytep)near_data == data)
+   {
+      WRITEFILE(io_ptr, near_data, length, check);
+   }
+   else
+   {
+      png_byte buf[NEAR_BUF_SIZE];
+      png_size_t written, remaining, err;
+      check = 0;
+      remaining = length;
+      do
+      {
+         written = MIN(NEAR_BUF_SIZE, remaining);
+         png_memcpy(buf, data, written); /* copy far buffer to near buffer */
+         WRITEFILE(io_ptr, buf, written, err);
+         if (err != written)
+            break;
+         else
+            check += err;
+         data += written;
+         remaining -= written;
+      }
+      while (remaining != 0);
+   }
+   if (check != length)
+   {
+      png_error(png_ptr, "Write Error");
+   }
+}
+
+#endif /* USE_FAR_KEYWORD */
+
+/* This function is called when there is a warning, but the library thinks
+ * it can continue anyway.  Replacement functions don't have to do anything
+ * here if you don't want to.  In the default configuration, png_ptr is
+ * not used, but it is passed in case it may be useful.
+ */
+static void
+pngtest_warning(png_structp png_ptr, png_const_charp message)
+{
+   PNG_CONST char *name = "UNKNOWN (ERROR!)";
+   if (png_ptr != NULL && png_ptr->error_ptr != NULL)
+      name = png_ptr->error_ptr;
+   fprintf(STDERR, "%s: libpng warning: %s\n", name, message);
+}
+
+/* This is the default error handling function.  Note that replacements for
+ * this function MUST NOT RETURN, or the program will likely crash.  This
+ * function is used by default, or if the program supplies NULL for the
+ * error function pointer in png_set_error_fn().
+ */
+static void
+pngtest_error(png_structp png_ptr, png_const_charp message)
+{
+   pngtest_warning(png_ptr, message);
+   /* We can return because png_error calls the default handler, which is
+    * actually OK in this case. */
+}
+#endif /* PNG_NO_STDIO */
+/* END of code to validate stdio-free compilation */
+
+/* START of code to validate memory allocation and deallocation */
+#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
+
+/* Allocate memory.  For reasonable files, size should never exceed
+   64K.  However, zlib may allocate more then 64K if you don't tell
+   it not to.  See zconf.h and png.h for more information.  zlib does
+   need to allocate exactly 64K, so whatever you call here must
+   have the ability to do that.
+
+   This piece of code can be compiled to validate max 64K allocations
+   by setting MAXSEG_64K in zlib zconf.h *or* PNG_MAX_MALLOC_64K. */
+typedef struct memory_information
+{
+   png_uint_32               size;
+   png_voidp                 pointer;
+   struct memory_information FAR *next;
+} memory_information;
+typedef memory_information FAR *memory_infop;
+
+static memory_infop pinformation = NULL;
+static int current_allocation = 0;
+static int maximum_allocation = 0;
+static int total_allocation = 0;
+static int num_allocations = 0;
+
+png_voidp png_debug_malloc PNGARG((png_structp png_ptr, png_uint_32 size));
+void png_debug_free PNGARG((png_structp png_ptr, png_voidp ptr));
+
+png_voidp
+png_debug_malloc(png_structp png_ptr, png_uint_32 size)
+{
+
+   /* png_malloc has already tested for NULL; png_create_struct calls
+      png_debug_malloc directly, with png_ptr == NULL which is OK */
+
+   if (size == 0)
+      return (NULL);
+
+   /* This calls the library allocator twice, once to get the requested
+      buffer and once to get a new free list entry. */
+   {
+      /* Disable malloc_fn and free_fn */
+      memory_infop pinfo;
+      png_set_mem_fn(png_ptr, NULL, NULL, NULL);
+      pinfo = (memory_infop)png_malloc(png_ptr,
+         (png_uint_32)png_sizeof (*pinfo));
+      pinfo->size = size;
+      current_allocation += size;
+      total_allocation += size;
+      num_allocations ++;
+      if (current_allocation > maximum_allocation)
+         maximum_allocation = current_allocation;
+      pinfo->pointer = (png_voidp)png_malloc(png_ptr, size);
+      /* Restore malloc_fn and free_fn */
+      png_set_mem_fn(png_ptr, png_voidp_NULL, (png_malloc_ptr)png_debug_malloc,
+         (png_free_ptr)png_debug_free);
+      if (size != 0 && pinfo->pointer == NULL)
+      {
+         current_allocation -= size;
+         total_allocation -= size;
+         png_error(png_ptr,
+           "out of memory in pngtest->png_debug_malloc.");
+      }
+      pinfo->next = pinformation;
+      pinformation = pinfo;
+      /* Make sure the caller isn't assuming zeroed memory. */
+      png_memset(pinfo->pointer, 0xdd, pinfo->size);
+      if(verbose)
+         printf("png_malloc %lu bytes at %x\n",size,pinfo->pointer);
+      assert(pinfo->size != 12345678);
+      return (png_voidp)(pinfo->pointer);
+   }
+}
+
+/* Free a pointer.  It is removed from the list at the same time. */
+void
+png_debug_free(png_structp png_ptr, png_voidp ptr)
+{
+   if (png_ptr == NULL)
+      fprintf(STDERR, "NULL pointer to png_debug_free.\n");
+   if (ptr == 0)
+   {
+#if 0 /* This happens all the time. */
+      fprintf(STDERR, "WARNING: freeing NULL pointer\n");
+#endif
+      return;
+   }
+
+   /* Unlink the element from the list. */
+   {
+      memory_infop FAR *ppinfo = &pinformation;
+      for (;;)
+      {
+         memory_infop pinfo = *ppinfo;
+         if (pinfo->pointer == ptr)
+         {
+            *ppinfo = pinfo->next;
+            current_allocation -= pinfo->size;
+            if (current_allocation < 0)
+               fprintf(STDERR, "Duplicate free of memory\n");
+            /* We must free the list element too, but first kill
+               the memory that is to be freed. */
+            png_memset(ptr, 0x55, pinfo->size);
+            png_free_default(png_ptr, pinfo);
+            pinfo=NULL;
+            break;
+         }
+         if (pinfo->next == NULL)
+         {
+            fprintf(STDERR, "Pointer %x not found\n", (unsigned int)ptr);
+            break;
+         }
+         ppinfo = &pinfo->next;
+      }
+   }
+
+   /* Finally free the data. */
+   if(verbose)
+      printf("Freeing %x\n",ptr);
+   png_free_default(png_ptr, ptr);
+   ptr=NULL;
+}
+#endif /* PNG_USER_MEM_SUPPORTED && PNG_DEBUG */
+/* END of code to test memory allocation/deallocation */
+
+/* Test one file */
+int
+test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
+{
+   static png_FILE_p fpin;
+   static png_FILE_p fpout;  /* "static" prevents setjmp corruption */
+   png_structp read_ptr;
+   png_infop read_info_ptr, end_info_ptr;
+#ifdef PNG_WRITE_SUPPORTED
+   png_structp write_ptr;
+   png_infop write_info_ptr;
+   png_infop write_end_info_ptr;
+#else
+   png_structp write_ptr = NULL;
+   png_infop write_info_ptr = NULL;
+   png_infop write_end_info_ptr = NULL;
+#endif
+   png_bytep row_buf;
+   png_uint_32 y;
+   png_uint_32 width, height;
+   int num_pass, pass;
+   int bit_depth, color_type;
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+   jmp_buf jmpbuf;
+#endif
+#endif
+
+#if defined(_WIN32_WCE)
+   TCHAR path[MAX_PATH];
+#endif
+   char inbuf[256], outbuf[256];
+
+   row_buf = NULL;
+
+#if defined(_WIN32_WCE)
+   MultiByteToWideChar(CP_ACP, 0, inname, -1, path, MAX_PATH);
+   if ((fpin = CreateFile(path, GENERIC_READ, 0, NULL, OPEN_EXISTING, 0, NULL)) == INVALID_HANDLE_VALUE)
+#else
+   if ((fpin = fopen(inname, "rb")) == NULL)
+#endif
+   {
+      fprintf(STDERR, "Could not find input file %s\n", inname);
+      return (1);
+   }
+
+#if defined(_WIN32_WCE)
+   MultiByteToWideChar(CP_ACP, 0, outname, -1, path, MAX_PATH);
+   if ((fpout = CreateFile(path, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, 0, NULL)) == INVALID_HANDLE_VALUE)
+#else
+   if ((fpout = fopen(outname, "wb")) == NULL)
+#endif
+   {
+      fprintf(STDERR, "Could not open output file %s\n", outname);
+      FCLOSE(fpin);
+      return (1);
+   }
+
+   png_debug(0, "Allocating read and write structures\n");
+#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
+   read_ptr = png_create_read_struct_2(PNG_LIBPNG_VER_STRING, png_voidp_NULL,
+      png_error_ptr_NULL, png_error_ptr_NULL, png_voidp_NULL,
+      (png_malloc_ptr)png_debug_malloc, (png_free_ptr)png_debug_free);
+#else
+   read_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, png_voidp_NULL,
+      png_error_ptr_NULL, png_error_ptr_NULL);
+#endif
+#if defined(PNG_NO_STDIO)
+   png_set_error_fn(read_ptr, (png_voidp)inname, pngtest_error,
+       pngtest_warning);
+#endif
+#ifdef PNG_WRITE_SUPPORTED
+#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
+   write_ptr = png_create_write_struct_2(PNG_LIBPNG_VER_STRING, png_voidp_NULL,
+      png_error_ptr_NULL, png_error_ptr_NULL, png_voidp_NULL,
+      (png_malloc_ptr)png_debug_malloc, (png_free_ptr)png_debug_free);
+#else
+   write_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, png_voidp_NULL,
+      png_error_ptr_NULL, png_error_ptr_NULL);
+#endif
+#if defined(PNG_NO_STDIO)
+   png_set_error_fn(write_ptr, (png_voidp)inname, pngtest_error,
+       pngtest_warning);
+#endif
+#endif
+   png_debug(0, "Allocating read_info, write_info and end_info structures\n");
+   read_info_ptr = png_create_info_struct(read_ptr);
+   end_info_ptr = png_create_info_struct(read_ptr);
+#ifdef PNG_WRITE_SUPPORTED
+   write_info_ptr = png_create_info_struct(write_ptr);
+   write_end_info_ptr = png_create_info_struct(write_ptr);
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+   png_debug(0, "Setting jmpbuf for read struct\n");
+#ifdef USE_FAR_KEYWORD
+   if (setjmp(jmpbuf))
+#else
+   if (setjmp(png_jmpbuf(read_ptr)))
+#endif
+   {
+      fprintf(STDERR, "%s -> %s: libpng read error\n", inname, outname);
+      if (row_buf)
+         png_free(read_ptr, row_buf);
+      png_destroy_read_struct(&read_ptr, &read_info_ptr, &end_info_ptr);
+#ifdef PNG_WRITE_SUPPORTED
+      png_destroy_info_struct(write_ptr, &write_end_info_ptr);
+      png_destroy_write_struct(&write_ptr, &write_info_ptr);
+#endif
+      FCLOSE(fpin);
+      FCLOSE(fpout);
+      return (1);
+   }
+#ifdef USE_FAR_KEYWORD
+   png_memcpy(png_jmpbuf(read_ptr),jmpbuf,png_sizeof(jmp_buf));
+#endif
+
+#ifdef PNG_WRITE_SUPPORTED
+   png_debug(0, "Setting jmpbuf for write struct\n");
+#ifdef USE_FAR_KEYWORD
+   if (setjmp(jmpbuf))
+#else
+   if (setjmp(png_jmpbuf(write_ptr)))
+#endif
+   {
+      fprintf(STDERR, "%s -> %s: libpng write error\n", inname, outname);
+      png_destroy_read_struct(&read_ptr, &read_info_ptr, &end_info_ptr);
+      png_destroy_info_struct(write_ptr, &write_end_info_ptr);
+#ifdef PNG_WRITE_SUPPORTED
+      png_destroy_write_struct(&write_ptr, &write_info_ptr);
+#endif
+      FCLOSE(fpin);
+      FCLOSE(fpout);
+      return (1);
+   }
+#ifdef USE_FAR_KEYWORD
+   png_memcpy(png_jmpbuf(write_ptr),jmpbuf,png_sizeof(jmp_buf));
+#endif
+#endif
+#endif
+
+   png_debug(0, "Initializing input and output streams\n");
+#if !defined(PNG_NO_STDIO)
+   png_init_io(read_ptr, fpin);
+#  ifdef PNG_WRITE_SUPPORTED
+   png_init_io(write_ptr, fpout);
+#  endif
+#else
+   png_set_read_fn(read_ptr, (png_voidp)fpin, pngtest_read_data);
+#  ifdef PNG_WRITE_SUPPORTED
+   png_set_write_fn(write_ptr, (png_voidp)fpout,  pngtest_write_data,
+#    if defined(PNG_WRITE_FLUSH_SUPPORTED)
+      pngtest_flush);
+#    else
+      NULL);
+#    endif
+#  endif
+#endif
+   if(status_dots_requested == 1)
+   {
+#ifdef PNG_WRITE_SUPPORTED
+      png_set_write_status_fn(write_ptr, write_row_callback);
+#endif
+      png_set_read_status_fn(read_ptr, read_row_callback);
+   }
+   else
+   {
+#ifdef PNG_WRITE_SUPPORTED
+      png_set_write_status_fn(write_ptr, png_write_status_ptr_NULL);
+#endif
+      png_set_read_status_fn(read_ptr, png_read_status_ptr_NULL);
+   }
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+   {
+     int i;
+     for(i=0; i<256; i++)
+        filters_used[i]=0;
+     png_set_read_user_transform_fn(read_ptr, count_filters);
+   }
+#endif
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+   zero_samples=0;
+   png_set_write_user_transform_fn(write_ptr, count_zero_samples);
+#endif
+
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+#  ifndef PNG_HANDLE_CHUNK_ALWAYS
+#    define PNG_HANDLE_CHUNK_ALWAYS       3
+#  endif
+   png_set_keep_unknown_chunks(read_ptr, PNG_HANDLE_CHUNK_ALWAYS,
+      png_bytep_NULL, 0);
+#endif
+#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
+#  ifndef PNG_HANDLE_CHUNK_IF_SAFE
+#    define PNG_HANDLE_CHUNK_IF_SAFE      2
+#  endif
+   png_set_keep_unknown_chunks(write_ptr, PNG_HANDLE_CHUNK_IF_SAFE,
+      png_bytep_NULL, 0);
+#endif
+
+   png_debug(0, "Reading info struct\n");
+   png_read_info(read_ptr, read_info_ptr);
+
+   png_debug(0, "Transferring info struct\n");
+   {
+      int interlace_type, compression_type, filter_type;
+
+      if (png_get_IHDR(read_ptr, read_info_ptr, &width, &height, &bit_depth,
+          &color_type, &interlace_type, &compression_type, &filter_type))
+      {
+         png_set_IHDR(write_ptr, write_info_ptr, width, height, bit_depth,
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+            color_type, interlace_type, compression_type, filter_type);
+#else
+            color_type, PNG_INTERLACE_NONE, compression_type, filter_type);
+#endif
+      }
+   }
+#if defined(PNG_FIXED_POINT_SUPPORTED)
+#if defined(PNG_cHRM_SUPPORTED)
+   {
+      png_fixed_point white_x, white_y, red_x, red_y, green_x, green_y, blue_x,
+         blue_y;
+      if (png_get_cHRM_fixed(read_ptr, read_info_ptr, &white_x, &white_y, &red_x,
+         &red_y, &green_x, &green_y, &blue_x, &blue_y))
+      {
+         png_set_cHRM_fixed(write_ptr, write_info_ptr, white_x, white_y, red_x,
+            red_y, green_x, green_y, blue_x, blue_y);
+      }
+   }
+#endif
+#if defined(PNG_gAMA_SUPPORTED)
+   {
+      png_fixed_point gamma;
+
+      if (png_get_gAMA_fixed(read_ptr, read_info_ptr, &gamma))
+      {
+         png_set_gAMA_fixed(write_ptr, write_info_ptr, gamma);
+      }
+   }
+#endif
+#else /* Use floating point versions */
+#if defined(PNG_FLOATING_POINT_SUPPORTED)
+#if defined(PNG_cHRM_SUPPORTED)
+   {
+      double white_x, white_y, red_x, red_y, green_x, green_y, blue_x,
+         blue_y;
+      if (png_get_cHRM(read_ptr, read_info_ptr, &white_x, &white_y, &red_x,
+         &red_y, &green_x, &green_y, &blue_x, &blue_y))
+      {
+         png_set_cHRM(write_ptr, write_info_ptr, white_x, white_y, red_x,
+            red_y, green_x, green_y, blue_x, blue_y);
+      }
+   }
+#endif
+#if defined(PNG_gAMA_SUPPORTED)
+   {
+      double gamma;
+
+      if (png_get_gAMA(read_ptr, read_info_ptr, &gamma))
+      {
+         png_set_gAMA(write_ptr, write_info_ptr, gamma);
+      }
+   }
+#endif
+#endif /* floating point */
+#endif /* fixed point */
+#if defined(PNG_iCCP_SUPPORTED)
+   {
+      png_charp name;
+      png_charp profile;
+      png_uint_32 proflen;
+      int compression_type;
+
+      if (png_get_iCCP(read_ptr, read_info_ptr, &name, &compression_type,
+                      &profile, &proflen))
+      {
+         png_set_iCCP(write_ptr, write_info_ptr, name, compression_type,
+                      profile, proflen);
+      }
+   }
+#endif
+#if defined(PNG_sRGB_SUPPORTED)
+   {
+      int intent;
+
+      if (png_get_sRGB(read_ptr, read_info_ptr, &intent))
+      {
+         png_set_sRGB(write_ptr, write_info_ptr, intent);
+      }
+   }
+#endif
+   {
+      png_colorp palette;
+      int num_palette;
+
+      if (png_get_PLTE(read_ptr, read_info_ptr, &palette, &num_palette))
+      {
+         png_set_PLTE(write_ptr, write_info_ptr, palette, num_palette);
+      }
+   }
+#if defined(PNG_bKGD_SUPPORTED)
+   {
+      png_color_16p background;
+
+      if (png_get_bKGD(read_ptr, read_info_ptr, &background))
+      {
+         png_set_bKGD(write_ptr, write_info_ptr, background);
+      }
+   }
+#endif
+#if defined(PNG_hIST_SUPPORTED)
+   {
+      png_uint_16p hist;
+
+      if (png_get_hIST(read_ptr, read_info_ptr, &hist))
+      {
+         png_set_hIST(write_ptr, write_info_ptr, hist);
+      }
+   }
+#endif
+#if defined(PNG_oFFs_SUPPORTED)
+   {
+      png_int_32 offset_x, offset_y;
+      int unit_type;
+
+      if (png_get_oFFs(read_ptr, read_info_ptr,&offset_x,&offset_y,&unit_type))
+      {
+         png_set_oFFs(write_ptr, write_info_ptr, offset_x, offset_y, unit_type);
+      }
+   }
+#endif
+#if defined(PNG_pCAL_SUPPORTED)
+   {
+      png_charp purpose, units;
+      png_charpp params;
+      png_int_32 X0, X1;
+      int type, nparams;
+
+      if (png_get_pCAL(read_ptr, read_info_ptr, &purpose, &X0, &X1, &type,
+         &nparams, &units, &params))
+      {
+         png_set_pCAL(write_ptr, write_info_ptr, purpose, X0, X1, type,
+            nparams, units, params);
+      }
+   }
+#endif
+#if defined(PNG_pHYs_SUPPORTED)
+   {
+      png_uint_32 res_x, res_y;
+      int unit_type;
+
+      if (png_get_pHYs(read_ptr, read_info_ptr, &res_x, &res_y, &unit_type))
+      {
+         png_set_pHYs(write_ptr, write_info_ptr, res_x, res_y, unit_type);
+      }
+   }
+#endif
+#if defined(PNG_sBIT_SUPPORTED)
+   {
+      png_color_8p sig_bit;
+
+      if (png_get_sBIT(read_ptr, read_info_ptr, &sig_bit))
+      {
+         png_set_sBIT(write_ptr, write_info_ptr, sig_bit);
+      }
+   }
+#endif
+#if defined(PNG_sCAL_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   {
+      int unit;
+      double scal_width, scal_height;
+
+      if (png_get_sCAL(read_ptr, read_info_ptr, &unit, &scal_width,
+         &scal_height))
+      {
+         png_set_sCAL(write_ptr, write_info_ptr, unit, scal_width, scal_height);
+      }
+   }
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   {
+      int unit;
+      png_charp scal_width, scal_height;
+
+      if (png_get_sCAL_s(read_ptr, read_info_ptr, &unit, &scal_width,
+          &scal_height))
+      {
+         png_set_sCAL_s(write_ptr, write_info_ptr, unit, scal_width, scal_height);
+      }
+   }
+#endif
+#endif
+#endif
+#if defined(PNG_TEXT_SUPPORTED)
+   {
+      png_textp text_ptr;
+      int num_text;
+
+      if (png_get_text(read_ptr, read_info_ptr, &text_ptr, &num_text) > 0)
+      {
+         png_debug1(0, "Handling %d iTXt/tEXt/zTXt chunks\n", num_text);
+         png_set_text(write_ptr, write_info_ptr, text_ptr, num_text);
+      }
+   }
+#endif
+#if defined(PNG_tIME_SUPPORTED)
+   {
+      png_timep mod_time;
+
+      if (png_get_tIME(read_ptr, read_info_ptr, &mod_time))
+      {
+         png_set_tIME(write_ptr, write_info_ptr, mod_time);
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+         /* we have to use png_strcpy instead of "=" because the string
+            pointed to by png_convert_to_rfc1123() gets free'ed before
+            we use it */
+         png_strcpy(tIME_string,png_convert_to_rfc1123(read_ptr, mod_time));
+         tIME_chunk_present++;
+#endif /* PNG_TIME_RFC1123_SUPPORTED */
+      }
+   }
+#endif
+#if defined(PNG_tRNS_SUPPORTED)
+   {
+      png_bytep trans;
+      int num_trans;
+      png_color_16p trans_values;
+
+      if (png_get_tRNS(read_ptr, read_info_ptr, &trans, &num_trans,
+         &trans_values))
+      {
+         png_set_tRNS(write_ptr, write_info_ptr, trans, num_trans,
+            trans_values);
+      }
+   }
+#endif
+#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
+   {
+      png_unknown_chunkp unknowns;
+      int num_unknowns = (int)png_get_unknown_chunks(read_ptr, read_info_ptr,
+         &unknowns);
+      if (num_unknowns)
+      {
+         png_size_t i;
+         png_set_unknown_chunks(write_ptr, write_info_ptr, unknowns,
+           num_unknowns);
+         /* copy the locations from the read_info_ptr.  The automatically
+            generated locations in write_info_ptr are wrong because we
+            haven't written anything yet */
+         for (i = 0; i < (png_size_t)num_unknowns; i++)
+           png_set_unknown_chunk_location(write_ptr, write_info_ptr, i,
+             unknowns[i].location);
+      }
+   }
+#endif
+
+#ifdef PNG_WRITE_SUPPORTED
+   png_debug(0, "\nWriting info struct\n");
+
+/* If we wanted, we could write info in two steps:
+   png_write_info_before_PLTE(write_ptr, write_info_ptr);
+ */
+   png_write_info(write_ptr, write_info_ptr);
+#endif
+
+#ifdef SINGLE_ROWBUF_ALLOC
+   png_debug(0, "\nAllocating row buffer...");
+   row_buf = (png_bytep)png_malloc(read_ptr,
+      png_get_rowbytes(read_ptr, read_info_ptr));
+   png_debug1(0, "0x%08lx\n\n", (unsigned long)row_buf);
+#endif /* SINGLE_ROWBUF_ALLOC */
+   png_debug(0, "Writing row data\n");
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
+  defined(PNG_WRITE_INTERLACING_SUPPORTED)
+   num_pass = png_set_interlace_handling(read_ptr);
+#  ifdef PNG_WRITE_SUPPORTED
+   png_set_interlace_handling(write_ptr);
+#  endif
+#else
+   num_pass=1;
+#endif
+
+#ifdef PNGTEST_TIMING
+   t_stop = (float)clock();
+   t_misc += (t_stop - t_start);
+   t_start = t_stop;
+#endif
+   for (pass = 0; pass < num_pass; pass++)
+   {
+      png_debug1(0, "Writing row data for pass %d\n",pass);
+      for (y = 0; y < height; y++)
+      {
+#ifndef SINGLE_ROWBUF_ALLOC
+         png_debug2(0, "\nAllocating row buffer (pass %d, y = %ld)...", pass,y);
+         row_buf = (png_bytep)png_malloc(read_ptr,
+            png_get_rowbytes(read_ptr, read_info_ptr));
+         png_debug2(0, "0x%08lx (%ld bytes)\n", (unsigned long)row_buf,
+            png_get_rowbytes(read_ptr, read_info_ptr));
+#endif /* !SINGLE_ROWBUF_ALLOC */
+         png_read_rows(read_ptr, (png_bytepp)&row_buf, png_bytepp_NULL, 1);
+
+#ifdef PNG_WRITE_SUPPORTED
+#ifdef PNGTEST_TIMING
+         t_stop = (float)clock();
+         t_decode += (t_stop - t_start);
+         t_start = t_stop;
+#endif
+         png_write_rows(write_ptr, (png_bytepp)&row_buf, 1);
+#ifdef PNGTEST_TIMING
+         t_stop = (float)clock();
+         t_encode += (t_stop - t_start);
+         t_start = t_stop;
+#endif
+#endif /* PNG_WRITE_SUPPORTED */
+
+#ifndef SINGLE_ROWBUF_ALLOC
+         png_debug2(0, "Freeing row buffer (pass %d, y = %ld)\n\n", pass, y);
+         png_free(read_ptr, row_buf);
+#endif /* !SINGLE_ROWBUF_ALLOC */
+      }
+   }
+
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+   png_free_data(read_ptr, read_info_ptr, PNG_FREE_UNKN, -1);
+#endif
+#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
+   png_free_data(write_ptr, write_info_ptr, PNG_FREE_UNKN, -1);
+#endif
+
+   png_debug(0, "Reading and writing end_info data\n");
+
+   png_read_end(read_ptr, end_info_ptr);
+#if defined(PNG_TEXT_SUPPORTED)
+   {
+      png_textp text_ptr;
+      int num_text;
+
+      if (png_get_text(read_ptr, end_info_ptr, &text_ptr, &num_text) > 0)
+      {
+         png_debug1(0, "Handling %d iTXt/tEXt/zTXt chunks\n", num_text);
+         png_set_text(write_ptr, write_end_info_ptr, text_ptr, num_text);
+      }
+   }
+#endif
+#if defined(PNG_tIME_SUPPORTED)
+   {
+      png_timep mod_time;
+
+      if (png_get_tIME(read_ptr, end_info_ptr, &mod_time))
+      {
+         png_set_tIME(write_ptr, write_end_info_ptr, mod_time);
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+         /* we have to use png_strcpy instead of "=" because the string
+            pointed to by png_convert_to_rfc1123() gets free'ed before
+            we use it */
+         png_strcpy(tIME_string,png_convert_to_rfc1123(read_ptr, mod_time));
+         tIME_chunk_present++;
+#endif /* PNG_TIME_RFC1123_SUPPORTED */
+      }
+   }
+#endif
+#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
+   {
+      png_unknown_chunkp unknowns;
+      int num_unknowns;
+      num_unknowns = (int)png_get_unknown_chunks(read_ptr, end_info_ptr,
+         &unknowns);
+      if (num_unknowns)
+      {
+         png_size_t i;
+         png_set_unknown_chunks(write_ptr, write_end_info_ptr, unknowns,
+           num_unknowns);
+         /* copy the locations from the read_info_ptr.  The automatically
+            generated locations in write_end_info_ptr are wrong because we
+            haven't written the end_info yet */
+         for (i = 0; i < (png_size_t)num_unknowns; i++)
+           png_set_unknown_chunk_location(write_ptr, write_end_info_ptr, i,
+             unknowns[i].location);
+      }
+   }
+#endif
+#ifdef PNG_WRITE_SUPPORTED
+   png_write_end(write_ptr, write_end_info_ptr);
+#endif
+
+#ifdef PNG_EASY_ACCESS_SUPPORTED
+   if(verbose)
+   {
+      png_uint_32 iwidth, iheight;
+      iwidth = png_get_image_width(write_ptr, write_info_ptr);
+      iheight = png_get_image_height(write_ptr, write_info_ptr);
+      fprintf(STDERR, "Image width = %lu, height = %lu\n",
+         iwidth, iheight);
+   }
+#endif
+
+   png_debug(0, "Destroying data structs\n");
+#ifdef SINGLE_ROWBUF_ALLOC
+   png_debug(1, "destroying row_buf for read_ptr\n");
+   png_free(read_ptr, row_buf);
+   row_buf=NULL;
+#endif /* SINGLE_ROWBUF_ALLOC */
+   png_debug(1, "destroying read_ptr, read_info_ptr, end_info_ptr\n");
+   png_destroy_read_struct(&read_ptr, &read_info_ptr, &end_info_ptr);
+#ifdef PNG_WRITE_SUPPORTED
+   png_debug(1, "destroying write_end_info_ptr\n");
+   png_destroy_info_struct(write_ptr, &write_end_info_ptr);
+   png_debug(1, "destroying write_ptr, write_info_ptr\n");
+   png_destroy_write_struct(&write_ptr, &write_info_ptr);
+#endif
+   png_debug(0, "Destruction complete.\n");
+
+   FCLOSE(fpin);
+   FCLOSE(fpout);
+
+   png_debug(0, "Opening files for comparison\n");
+#if defined(_WIN32_WCE)
+   MultiByteToWideChar(CP_ACP, 0, inname, -1, path, MAX_PATH);
+   if ((fpin = CreateFile(path, GENERIC_READ, 0, NULL, OPEN_EXISTING, 0, NULL)) == INVALID_HANDLE_VALUE)
+#else
+   if ((fpin = fopen(inname, "rb")) == NULL)
+#endif
+   {
+      fprintf(STDERR, "Could not find file %s\n", inname);
+      return (1);
+   }
+
+#if defined(_WIN32_WCE)
+   MultiByteToWideChar(CP_ACP, 0, outname, -1, path, MAX_PATH);
+   if ((fpout = CreateFile(path, GENERIC_READ, 0, NULL, OPEN_EXISTING, 0, NULL)) == INVALID_HANDLE_VALUE)
+#else
+   if ((fpout = fopen(outname, "rb")) == NULL)
+#endif
+   {
+      fprintf(STDERR, "Could not find file %s\n", outname);
+      FCLOSE(fpin);
+      return (1);
+   }
+
+   for(;;)
+   {
+      png_size_t num_in, num_out;
+
+      READFILE(fpin, inbuf, 1, num_in);
+      READFILE(fpout, outbuf, 1, num_out);
+
+      if (num_in != num_out)
+      {
+         fprintf(STDERR, "\nFiles %s and %s are of a different size\n",
+                 inname, outname);
+         if(wrote_question == 0)
+         {
+            fprintf(STDERR,
+         "   Was %s written with the same maximum IDAT chunk size (%d bytes),",
+              inname,PNG_ZBUF_SIZE);
+            fprintf(STDERR,
+              "\n   filtering heuristic (libpng default), compression");
+            fprintf(STDERR,
+              " level (zlib default),\n   and zlib version (%s)?\n\n",
+              ZLIB_VERSION);
+            wrote_question=1;
+         }
+         FCLOSE(fpin);
+         FCLOSE(fpout);
+         return (0);
+      }
+
+      if (!num_in)
+         break;
+
+      if (png_memcmp(inbuf, outbuf, num_in))
+      {
+         fprintf(STDERR, "\nFiles %s and %s are different\n", inname, outname);
+         if(wrote_question == 0)
+         {
+            fprintf(STDERR,
+         "   Was %s written with the same maximum IDAT chunk size (%d bytes),",
+                 inname,PNG_ZBUF_SIZE);
+            fprintf(STDERR,
+              "\n   filtering heuristic (libpng default), compression");
+            fprintf(STDERR,
+              " level (zlib default),\n   and zlib version (%s)?\n\n",
+              ZLIB_VERSION);
+            wrote_question=1;
+         }
+         FCLOSE(fpin);
+         FCLOSE(fpout);
+         return (0);
+      }
+   }
+
+   FCLOSE(fpin);
+   FCLOSE(fpout);
+
+   return (0);
+}
+
+/* input and output filenames */
+#ifdef RISCOS
+static PNG_CONST char *inname = "pngtest/png";
+static PNG_CONST char *outname = "pngout/png";
+#else
+static PNG_CONST char *inname = "pngtest.png";
+static PNG_CONST char *outname = "pngout.png";
+#endif
+
+int
+main(int argc, char *argv[])
+{
+   int multiple = 0;
+   int ierror = 0;
+
+   fprintf(STDERR, "Testing libpng version %s\n", PNG_LIBPNG_VER_STRING);
+   fprintf(STDERR, "   with zlib   version %s\n", ZLIB_VERSION);
+   fprintf(STDERR,"%s",png_get_copyright(NULL));
+   /* Show the version of libpng used in building the library */
+   fprintf(STDERR," library (%lu):%s", png_access_version_number(),
+      png_get_header_version(NULL));
+   /* Show the version of libpng used in building the application */
+   fprintf(STDERR," pngtest (%lu):%s", (unsigned long)PNG_LIBPNG_VER,
+      PNG_HEADER_VERSION_STRING);
+   fprintf(STDERR," png_sizeof(png_struct)=%ld, png_sizeof(png_info)=%ld\n",
+                    (long)png_sizeof(png_struct), (long)png_sizeof(png_info));
+
+   /* Do some consistency checking on the memory allocation settings, I'm
+      not sure this matters, but it is nice to know, the first of these
+      tests should be impossible because of the way the macros are set
+      in pngconf.h */
+#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
+      fprintf(STDERR, " NOTE: Zlib compiled for max 64k, libpng not\n");
+#endif
+   /* I think the following can happen. */
+#if !defined(MAXSEG_64K) && defined(PNG_MAX_MALLOC_64K)
+      fprintf(STDERR, " NOTE: libpng compiled for max 64k, zlib not\n");
+#endif
+
+   if (strcmp(png_libpng_ver, PNG_LIBPNG_VER_STRING))
+   {
+      fprintf(STDERR,
+         "Warning: versions are different between png.h and png.c\n");
+      fprintf(STDERR, "  png.h version: %s\n", PNG_LIBPNG_VER_STRING);
+      fprintf(STDERR, "  png.c version: %s\n\n", png_libpng_ver);
+      ++ierror;
+   }
+
+   if (argc > 1)
+   {
+      if (strcmp(argv[1], "-m") == 0)
+      {
+         multiple = 1;
+         status_dots_requested = 0;
+      }
+      else if (strcmp(argv[1], "-mv") == 0 ||
+               strcmp(argv[1], "-vm") == 0 )
+      {
+         multiple = 1;
+         verbose = 1;
+         status_dots_requested = 1;
+      }
+      else if (strcmp(argv[1], "-v") == 0)
+      {
+         verbose = 1;
+         status_dots_requested = 1;
+         inname = argv[2];
+      }
+      else
+      {
+         inname = argv[1];
+         status_dots_requested = 0;
+      }
+   }
+
+   if (!multiple && argc == 3+verbose)
+     outname = argv[2+verbose];
+
+   if ((!multiple && argc > 3+verbose) || (multiple && argc < 2))
+   {
+     fprintf(STDERR,
+       "usage: %s [infile.png] [outfile.png]\n\t%s -m {infile.png}\n",
+        argv[0], argv[0]);
+     fprintf(STDERR,
+       "  reads/writes one PNG file (without -m) or multiple files (-m)\n");
+     fprintf(STDERR,
+       "  with -m %s is used as a temporary file\n", outname);
+     exit(1);
+   }
+
+   if (multiple)
+   {
+      int i;
+#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
+      int allocation_now = current_allocation;
+#endif
+      for (i=2; i<argc; ++i)
+      {
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+         int k;
+#endif
+         int kerror;
+         fprintf(STDERR, "Testing %s:",argv[i]);
+         kerror = test_one_file(argv[i], outname);
+         if (kerror == 0)
+         {
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+            fprintf(STDERR, "\n PASS (%lu zero samples)\n",zero_samples);
+#else
+            fprintf(STDERR, " PASS\n");
+#endif
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+            for (k=0; k<256; k++)
+               if(filters_used[k])
+                  fprintf(STDERR, " Filter %d was used %lu times\n",
+                     k,filters_used[k]);
+#endif
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+         if(tIME_chunk_present != 0)
+            fprintf(STDERR, " tIME = %s\n",tIME_string);
+         tIME_chunk_present = 0;
+#endif /* PNG_TIME_RFC1123_SUPPORTED */
+         }
+         else
+         {
+            fprintf(STDERR, " FAIL\n");
+            ierror += kerror;
+         }
+#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
+         if (allocation_now != current_allocation)
+            fprintf(STDERR, "MEMORY ERROR: %d bytes lost\n",
+               current_allocation-allocation_now);
+         if (current_allocation != 0)
+         {
+            memory_infop pinfo = pinformation;
+
+            fprintf(STDERR, "MEMORY ERROR: %d bytes still allocated\n",
+               current_allocation);
+            while (pinfo != NULL)
+            {
+               fprintf(STDERR, " %lu bytes at %x\n", pinfo->size, 
+                 (unsigned int) pinfo->pointer);
+               pinfo = pinfo->next;
+            }
+         }
+#endif
+      }
+#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
+         fprintf(STDERR, " Current memory allocation: %10d bytes\n",
+            current_allocation);
+         fprintf(STDERR, " Maximum memory allocation: %10d bytes\n",
+            maximum_allocation);
+         fprintf(STDERR, " Total   memory allocation: %10d bytes\n",
+            total_allocation);
+         fprintf(STDERR, "     Number of allocations: %10d\n",
+            num_allocations);
+#endif
+   }
+   else
+   {
+      int i;
+      for (i=0; i<3; ++i)
+      {
+         int kerror;
+#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
+         int allocation_now = current_allocation;
+#endif
+         if (i == 1) status_dots_requested = 1;
+         else if(verbose == 0)status_dots_requested = 0;
+         if (i == 0 || verbose == 1 || ierror != 0)
+            fprintf(STDERR, "Testing %s:",inname);
+         kerror = test_one_file(inname, outname);
+         if(kerror == 0)
+         {
+            if(verbose == 1 || i == 2)
+            {
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+                int k;
+#endif
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+                fprintf(STDERR, "\n PASS (%lu zero samples)\n",zero_samples);
+#else
+                fprintf(STDERR, " PASS\n");
+#endif
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+                for (k=0; k<256; k++)
+                   if(filters_used[k])
+                      fprintf(STDERR, " Filter %d was used %lu times\n",
+                         k,filters_used[k]);
+#endif
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+             if(tIME_chunk_present != 0)
+                fprintf(STDERR, " tIME = %s\n",tIME_string);
+#endif /* PNG_TIME_RFC1123_SUPPORTED */
+            }
+         }
+         else
+         {
+            if(verbose == 0 && i != 2)
+               fprintf(STDERR, "Testing %s:",inname);
+            fprintf(STDERR, " FAIL\n");
+            ierror += kerror;
+         }
+#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
+         if (allocation_now != current_allocation)
+             fprintf(STDERR, "MEMORY ERROR: %d bytes lost\n",
+               current_allocation-allocation_now);
+         if (current_allocation != 0)
+         {
+             memory_infop pinfo = pinformation;
+
+             fprintf(STDERR, "MEMORY ERROR: %d bytes still allocated\n",
+                current_allocation);
+             while (pinfo != NULL)
+             {
+                fprintf(STDERR," %lu bytes at %x\n",
+                   pinfo->size, (unsigned int)pinfo->pointer);
+                pinfo = pinfo->next;
+             }
+          }
+#endif
+       }
+#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
+       fprintf(STDERR, " Current memory allocation: %10d bytes\n",
+          current_allocation);
+       fprintf(STDERR, " Maximum memory allocation: %10d bytes\n",
+          maximum_allocation);
+       fprintf(STDERR, " Total   memory allocation: %10d bytes\n",
+          total_allocation);
+       fprintf(STDERR, "     Number of allocations: %10d\n",
+            num_allocations);
+#endif
+   }
+
+#ifdef PNGTEST_TIMING
+   t_stop = (float)clock();
+   t_misc += (t_stop - t_start);
+   t_start = t_stop;
+   fprintf(STDERR," CPU time used = %.3f seconds",
+      (t_misc+t_decode+t_encode)/(float)CLOCKS_PER_SEC);
+   fprintf(STDERR," (decoding %.3f,\n",
+      t_decode/(float)CLOCKS_PER_SEC);
+   fprintf(STDERR,"        encoding %.3f ,",
+      t_encode/(float)CLOCKS_PER_SEC);
+   fprintf(STDERR," other %.3f seconds)\n\n",
+      t_misc/(float)CLOCKS_PER_SEC);
+#endif
+
+   if (ierror == 0)
+      fprintf(STDERR, "libpng passes test\n");
+   else
+      fprintf(STDERR, "libpng FAILS test\n");
+   return (int)(ierror != 0);
+}
+
+/* Generate a compiler error if there is an old png.h in the search path. */
+typedef version_1_2_8 your_png_h_is_not_version_1_2_8;
diff --git a/gs/libpng/pngtest.png b/gs/libpng/pngtest.png
new file mode 100644
index 000000000..f3a6df448
--- /dev/null
+++ b/gs/libpng/pngtest.png
diff --git a/gs/libpng/pngtrans.c b/gs/libpng/pngtrans.c
new file mode 100644
index 000000000..9003a2109
--- /dev/null
+++ b/gs/libpng/pngtrans.c
@@ -0,0 +1,650 @@
+
+/* pngtrans.c - transforms the data in a row (used by both readers and writers)
+ *
+ * libpng  1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
+/* turn on BGR-to-RGB mapping */
+void PNGAPI
+png_set_bgr(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_bgr\n");
+   png_ptr->transformations |= PNG_BGR;
+}
+#endif
+
+#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
+/* turn on 16 bit byte swapping */
+void PNGAPI
+png_set_swap(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_swap\n");
+   if (png_ptr->bit_depth == 16)
+      png_ptr->transformations |= PNG_SWAP_BYTES;
+}
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+/* turn on pixel packing */
+void PNGAPI
+png_set_packing(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_packing\n");
+   if (png_ptr->bit_depth < 8)
+   {
+      png_ptr->transformations |= PNG_PACK;
+      png_ptr->usr_bit_depth = 8;
+   }
+}
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+/* turn on packed pixel swapping */
+void PNGAPI
+png_set_packswap(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_packswap\n");
+   if (png_ptr->bit_depth < 8)
+      png_ptr->transformations |= PNG_PACKSWAP;
+}
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
+void PNGAPI
+png_set_shift(png_structp png_ptr, png_color_8p true_bits)
+{
+   png_debug(1, "in png_set_shift\n");
+   png_ptr->transformations |= PNG_SHIFT;
+   png_ptr->shift = *true_bits;
+}
+#endif
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
+    defined(PNG_WRITE_INTERLACING_SUPPORTED)
+int PNGAPI
+png_set_interlace_handling(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_interlace handling\n");
+   if (png_ptr->interlaced)
+   {
+      png_ptr->transformations |= PNG_INTERLACE;
+      return (7);
+   }
+
+   return (1);
+}
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+/* Add a filler byte on read, or remove a filler or alpha byte on write.
+ * The filler type has changed in v0.95 to allow future 2-byte fillers
+ * for 48-bit input data, as well as to avoid problems with some compilers
+ * that don't like bytes as parameters.
+ */
+void PNGAPI
+png_set_filler(png_structp png_ptr, png_uint_32 filler, int filler_loc)
+{
+   png_debug(1, "in png_set_filler\n");
+   png_ptr->transformations |= PNG_FILLER;
+   png_ptr->filler = (png_byte)filler;
+   if (filler_loc == PNG_FILLER_AFTER)
+      png_ptr->flags |= PNG_FLAG_FILLER_AFTER;
+   else
+      png_ptr->flags &= ~PNG_FLAG_FILLER_AFTER;
+
+   /* This should probably go in the "do_read_filler" routine.
+    * I attempted to do that in libpng-1.0.1a but that caused problems
+    * so I restored it in libpng-1.0.2a
+   */
+
+   if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
+   {
+      png_ptr->usr_channels = 4;
+   }
+
+   /* Also I added this in libpng-1.0.2a (what happens when we expand
+    * a less-than-8-bit grayscale to GA? */
+
+   if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY && png_ptr->bit_depth >= 8)
+   {
+      png_ptr->usr_channels = 2;
+   }
+}
+
+#if !defined(PNG_1_0_X)
+/* Added to libpng-1.2.7 */
+void PNGAPI
+png_set_add_alpha(png_structp png_ptr, png_uint_32 filler, int filler_loc)
+{
+   png_debug(1, "in png_set_add_alpha\n");
+   png_set_filler(png_ptr, filler, filler_loc);
+   png_ptr->transformations |= PNG_ADD_ALPHA;
+}
+#endif
+
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
+    defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+void PNGAPI
+png_set_swap_alpha(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_swap_alpha\n");
+   png_ptr->transformations |= PNG_SWAP_ALPHA;
+}
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
+    defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+void PNGAPI
+png_set_invert_alpha(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_invert_alpha\n");
+   png_ptr->transformations |= PNG_INVERT_ALPHA;
+}
+#endif
+
+#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
+void PNGAPI
+png_set_invert_mono(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_invert_mono\n");
+   png_ptr->transformations |= PNG_INVERT_MONO;
+}
+
+/* invert monochrome grayscale data */
+void /* PRIVATE */
+png_do_invert(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_invert\n");
+  /* This test removed from libpng version 1.0.13 and 1.2.0:
+   *   if (row_info->bit_depth == 1 &&
+   */
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row == NULL || row_info == NULL)
+     return;
+#endif
+   if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
+   {
+      png_bytep rp = row;
+      png_uint_32 i;
+      png_uint_32 istop = row_info->rowbytes;
+
+      for (i = 0; i < istop; i++)
+      {
+         *rp = (png_byte)(~(*rp));
+         rp++;
+      }
+   }
+   else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
+      row_info->bit_depth == 8)
+   {
+      png_bytep rp = row;
+      png_uint_32 i;
+      png_uint_32 istop = row_info->rowbytes;
+
+      for (i = 0; i < istop; i+=2)
+      {
+         *rp = (png_byte)(~(*rp));
+         rp+=2;
+      }
+   }
+   else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
+      row_info->bit_depth == 16)
+   {
+      png_bytep rp = row;
+      png_uint_32 i;
+      png_uint_32 istop = row_info->rowbytes;
+
+      for (i = 0; i < istop; i+=4)
+      {
+         *rp = (png_byte)(~(*rp));
+         *(rp+1) = (png_byte)(~(*(rp+1)));
+         rp+=4;
+      }
+   }
+}
+#endif
+
+#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
+/* swaps byte order on 16 bit depth images */
+void /* PRIVATE */
+png_do_swap(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_swap\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+       row_info->bit_depth == 16)
+   {
+      png_bytep rp = row;
+      png_uint_32 i;
+      png_uint_32 istop= row_info->width * row_info->channels;
+
+      for (i = 0; i < istop; i++, rp += 2)
+      {
+         png_byte t = *rp;
+         *rp = *(rp + 1);
+         *(rp + 1) = t;
+      }
+   }
+}
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+static png_byte onebppswaptable[256] = {
+   0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0,
+   0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
+   0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8,
+   0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8,
+   0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4,
+   0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,
+   0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC,
+   0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC,
+   0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2,
+   0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2,
+   0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA,
+   0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,
+   0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6,
+   0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6,
+   0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE,
+   0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE,
+   0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1,
+   0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,
+   0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9,
+   0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9,
+   0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5,
+   0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5,
+   0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED,
+   0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,
+   0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3,
+   0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
+   0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB,
+   0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB,
+   0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7,
+   0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
+   0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF,
+   0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
+};
+
+static png_byte twobppswaptable[256] = {
+   0x00, 0x40, 0x80, 0xC0, 0x10, 0x50, 0x90, 0xD0,
+   0x20, 0x60, 0xA0, 0xE0, 0x30, 0x70, 0xB0, 0xF0,
+   0x04, 0x44, 0x84, 0xC4, 0x14, 0x54, 0x94, 0xD4,
+   0x24, 0x64, 0xA4, 0xE4, 0x34, 0x74, 0xB4, 0xF4,
+   0x08, 0x48, 0x88, 0xC8, 0x18, 0x58, 0x98, 0xD8,
+   0x28, 0x68, 0xA8, 0xE8, 0x38, 0x78, 0xB8, 0xF8,
+   0x0C, 0x4C, 0x8C, 0xCC, 0x1C, 0x5C, 0x9C, 0xDC,
+   0x2C, 0x6C, 0xAC, 0xEC, 0x3C, 0x7C, 0xBC, 0xFC,
+   0x01, 0x41, 0x81, 0xC1, 0x11, 0x51, 0x91, 0xD1,
+   0x21, 0x61, 0xA1, 0xE1, 0x31, 0x71, 0xB1, 0xF1,
+   0x05, 0x45, 0x85, 0xC5, 0x15, 0x55, 0x95, 0xD5,
+   0x25, 0x65, 0xA5, 0xE5, 0x35, 0x75, 0xB5, 0xF5,
+   0x09, 0x49, 0x89, 0xC9, 0x19, 0x59, 0x99, 0xD9,
+   0x29, 0x69, 0xA9, 0xE9, 0x39, 0x79, 0xB9, 0xF9,
+   0x0D, 0x4D, 0x8D, 0xCD, 0x1D, 0x5D, 0x9D, 0xDD,
+   0x2D, 0x6D, 0xAD, 0xED, 0x3D, 0x7D, 0xBD, 0xFD,
+   0x02, 0x42, 0x82, 0xC2, 0x12, 0x52, 0x92, 0xD2,
+   0x22, 0x62, 0xA2, 0xE2, 0x32, 0x72, 0xB2, 0xF2,
+   0x06, 0x46, 0x86, 0xC6, 0x16, 0x56, 0x96, 0xD6,
+   0x26, 0x66, 0xA6, 0xE6, 0x36, 0x76, 0xB6, 0xF6,
+   0x0A, 0x4A, 0x8A, 0xCA, 0x1A, 0x5A, 0x9A, 0xDA,
+   0x2A, 0x6A, 0xAA, 0xEA, 0x3A, 0x7A, 0xBA, 0xFA,
+   0x0E, 0x4E, 0x8E, 0xCE, 0x1E, 0x5E, 0x9E, 0xDE,
+   0x2E, 0x6E, 0xAE, 0xEE, 0x3E, 0x7E, 0xBE, 0xFE,
+   0x03, 0x43, 0x83, 0xC3, 0x13, 0x53, 0x93, 0xD3,
+   0x23, 0x63, 0xA3, 0xE3, 0x33, 0x73, 0xB3, 0xF3,
+   0x07, 0x47, 0x87, 0xC7, 0x17, 0x57, 0x97, 0xD7,
+   0x27, 0x67, 0xA7, 0xE7, 0x37, 0x77, 0xB7, 0xF7,
+   0x0B, 0x4B, 0x8B, 0xCB, 0x1B, 0x5B, 0x9B, 0xDB,
+   0x2B, 0x6B, 0xAB, 0xEB, 0x3B, 0x7B, 0xBB, 0xFB,
+   0x0F, 0x4F, 0x8F, 0xCF, 0x1F, 0x5F, 0x9F, 0xDF,
+   0x2F, 0x6F, 0xAF, 0xEF, 0x3F, 0x7F, 0xBF, 0xFF
+};
+
+static png_byte fourbppswaptable[256] = {
+   0x00, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x70,
+   0x80, 0x90, 0xA0, 0xB0, 0xC0, 0xD0, 0xE0, 0xF0,
+   0x01, 0x11, 0x21, 0x31, 0x41, 0x51, 0x61, 0x71,
+   0x81, 0x91, 0xA1, 0xB1, 0xC1, 0xD1, 0xE1, 0xF1,
+   0x02, 0x12, 0x22, 0x32, 0x42, 0x52, 0x62, 0x72,
+   0x82, 0x92, 0xA2, 0xB2, 0xC2, 0xD2, 0xE2, 0xF2,
+   0x03, 0x13, 0x23, 0x33, 0x43, 0x53, 0x63, 0x73,
+   0x83, 0x93, 0xA3, 0xB3, 0xC3, 0xD3, 0xE3, 0xF3,
+   0x04, 0x14, 0x24, 0x34, 0x44, 0x54, 0x64, 0x74,
+   0x84, 0x94, 0xA4, 0xB4, 0xC4, 0xD4, 0xE4, 0xF4,
+   0x05, 0x15, 0x25, 0x35, 0x45, 0x55, 0x65, 0x75,
+   0x85, 0x95, 0xA5, 0xB5, 0xC5, 0xD5, 0xE5, 0xF5,
+   0x06, 0x16, 0x26, 0x36, 0x46, 0x56, 0x66, 0x76,
+   0x86, 0x96, 0xA6, 0xB6, 0xC6, 0xD6, 0xE6, 0xF6,
+   0x07, 0x17, 0x27, 0x37, 0x47, 0x57, 0x67, 0x77,
+   0x87, 0x97, 0xA7, 0xB7, 0xC7, 0xD7, 0xE7, 0xF7,
+   0x08, 0x18, 0x28, 0x38, 0x48, 0x58, 0x68, 0x78,
+   0x88, 0x98, 0xA8, 0xB8, 0xC8, 0xD8, 0xE8, 0xF8,
+   0x09, 0x19, 0x29, 0x39, 0x49, 0x59, 0x69, 0x79,
+   0x89, 0x99, 0xA9, 0xB9, 0xC9, 0xD9, 0xE9, 0xF9,
+   0x0A, 0x1A, 0x2A, 0x3A, 0x4A, 0x5A, 0x6A, 0x7A,
+   0x8A, 0x9A, 0xAA, 0xBA, 0xCA, 0xDA, 0xEA, 0xFA,
+   0x0B, 0x1B, 0x2B, 0x3B, 0x4B, 0x5B, 0x6B, 0x7B,
+   0x8B, 0x9B, 0xAB, 0xBB, 0xCB, 0xDB, 0xEB, 0xFB,
+   0x0C, 0x1C, 0x2C, 0x3C, 0x4C, 0x5C, 0x6C, 0x7C,
+   0x8C, 0x9C, 0xAC, 0xBC, 0xCC, 0xDC, 0xEC, 0xFC,
+   0x0D, 0x1D, 0x2D, 0x3D, 0x4D, 0x5D, 0x6D, 0x7D,
+   0x8D, 0x9D, 0xAD, 0xBD, 0xCD, 0xDD, 0xED, 0xFD,
+   0x0E, 0x1E, 0x2E, 0x3E, 0x4E, 0x5E, 0x6E, 0x7E,
+   0x8E, 0x9E, 0xAE, 0xBE, 0xCE, 0xDE, 0xEE, 0xFE,
+   0x0F, 0x1F, 0x2F, 0x3F, 0x4F, 0x5F, 0x6F, 0x7F,
+   0x8F, 0x9F, 0xAF, 0xBF, 0xCF, 0xDF, 0xEF, 0xFF
+};
+
+/* swaps pixel packing order within bytes */
+void /* PRIVATE */
+png_do_packswap(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_packswap\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+       row_info->bit_depth < 8)
+   {
+      png_bytep rp, end, table;
+
+      end = row + row_info->rowbytes;
+
+      if (row_info->bit_depth == 1)
+         table = onebppswaptable;
+      else if (row_info->bit_depth == 2)
+         table = twobppswaptable;
+      else if (row_info->bit_depth == 4)
+         table = fourbppswaptable;
+      else
+         return;
+
+      for (rp = row; rp < end; rp++)
+         *rp = table[*rp];
+   }
+}
+#endif /* PNG_READ_PACKSWAP_SUPPORTED or PNG_WRITE_PACKSWAP_SUPPORTED */
+
+#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
+    defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+/* remove filler or alpha byte(s) */
+void /* PRIVATE */
+png_do_strip_filler(png_row_infop row_info, png_bytep row, png_uint_32 flags)
+{
+   png_debug(1, "in png_do_strip_filler\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL)
+#endif
+   {
+      png_bytep sp=row;
+      png_bytep dp=row;
+      png_uint_32 row_width=row_info->width;
+      png_uint_32 i;
+
+      if ((row_info->color_type == PNG_COLOR_TYPE_RGB ||
+         (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA &&
+         (flags & PNG_FLAG_STRIP_ALPHA))) &&
+         row_info->channels == 4)
+      {
+         if (row_info->bit_depth == 8)
+         {
+            /* This converts from RGBX or RGBA to RGB */
+            if (flags & PNG_FLAG_FILLER_AFTER)
+            {
+               dp+=3; sp+=4;
+               for (i = 1; i < row_width; i++)
+               {
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  sp++;
+               }
+            }
+            /* This converts from XRGB or ARGB to RGB */
+            else
+            {
+               for (i = 0; i < row_width; i++)
+               {
+                  sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+               }
+            }
+            row_info->pixel_depth = 24;
+            row_info->rowbytes = row_width * 3;
+         }
+         else /* if (row_info->bit_depth == 16) */
+         {
+            if (flags & PNG_FLAG_FILLER_AFTER)
+            {
+               /* This converts from RRGGBBXX or RRGGBBAA to RRGGBB */
+               sp += 8; dp += 6;
+               for (i = 1; i < row_width; i++)
+               {
+                  /* This could be (although png_memcpy is probably slower):
+                  png_memcpy(dp, sp, 6);
+                  sp += 8;
+                  dp += 6;
+                  */
+
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  sp += 2;
+               }
+            }
+            else
+            {
+               /* This converts from XXRRGGBB or AARRGGBB to RRGGBB */
+               for (i = 0; i < row_width; i++)
+               {
+                  /* This could be (although png_memcpy is probably slower):
+                  png_memcpy(dp, sp, 6);
+                  sp += 8;
+                  dp += 6;
+                  */
+
+                  sp+=2;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+               }
+            }
+            row_info->pixel_depth = 48;
+            row_info->rowbytes = row_width * 6;
+         }
+         row_info->channels = 3;
+      }
+      else if ((row_info->color_type == PNG_COLOR_TYPE_GRAY ||
+         (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
+         (flags & PNG_FLAG_STRIP_ALPHA))) &&
+          row_info->channels == 2)
+      {
+         if (row_info->bit_depth == 8)
+         {
+            /* This converts from GX or GA to G */
+            if (flags & PNG_FLAG_FILLER_AFTER)
+            {
+               for (i = 0; i < row_width; i++)
+               {
+                  *dp++ = *sp++;
+                  sp++;
+               }
+            }
+            /* This converts from XG or AG to G */
+            else
+            {
+               for (i = 0; i < row_width; i++)
+               {
+                  sp++;
+                  *dp++ = *sp++;
+               }
+            }
+            row_info->pixel_depth = 8;
+            row_info->rowbytes = row_width;
+         }
+         else /* if (row_info->bit_depth == 16) */
+         {
+            if (flags & PNG_FLAG_FILLER_AFTER)
+            {
+               /* This converts from GGXX or GGAA to GG */
+               sp += 4; dp += 2;
+               for (i = 1; i < row_width; i++)
+               {
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  sp += 2;
+               }
+            }
+            else
+            {
+               /* This converts from XXGG or AAGG to GG */
+               for (i = 0; i < row_width; i++)
+               {
+                  sp += 2;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+               }
+            }
+            row_info->pixel_depth = 16;
+            row_info->rowbytes = row_width * 2;
+         }
+         row_info->channels = 1;
+      }
+      if (flags & PNG_FLAG_STRIP_ALPHA)
+        row_info->color_type &= ~PNG_COLOR_MASK_ALPHA;
+   }
+}
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
+/* swaps red and blue bytes within a pixel */
+void /* PRIVATE */
+png_do_bgr(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_bgr\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+       (row_info->color_type & PNG_COLOR_MASK_COLOR))
+   {
+      png_uint_32 row_width = row_info->width;
+      if (row_info->bit_depth == 8)
+      {
+         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+         {
+            png_bytep rp;
+            png_uint_32 i;
+
+            for (i = 0, rp = row; i < row_width; i++, rp += 3)
+            {
+               png_byte save = *rp;
+               *rp = *(rp + 2);
+               *(rp + 2) = save;
+            }
+         }
+         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+         {
+            png_bytep rp;
+            png_uint_32 i;
+
+            for (i = 0, rp = row; i < row_width; i++, rp += 4)
+            {
+               png_byte save = *rp;
+               *rp = *(rp + 2);
+               *(rp + 2) = save;
+            }
+         }
+      }
+      else if (row_info->bit_depth == 16)
+      {
+         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+         {
+            png_bytep rp;
+            png_uint_32 i;
+
+            for (i = 0, rp = row; i < row_width; i++, rp += 6)
+            {
+               png_byte save = *rp;
+               *rp = *(rp + 4);
+               *(rp + 4) = save;
+               save = *(rp + 1);
+               *(rp + 1) = *(rp + 5);
+               *(rp + 5) = save;
+            }
+         }
+         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+         {
+            png_bytep rp;
+            png_uint_32 i;
+
+            for (i = 0, rp = row; i < row_width; i++, rp += 8)
+            {
+               png_byte save = *rp;
+               *rp = *(rp + 4);
+               *(rp + 4) = save;
+               save = *(rp + 1);
+               *(rp + 1) = *(rp + 5);
+               *(rp + 5) = save;
+            }
+         }
+      }
+   }
+}
+#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_LEGACY_SUPPORTED)
+void PNGAPI
+png_set_user_transform_info(png_structp png_ptr, png_voidp
+   user_transform_ptr, int user_transform_depth, int user_transform_channels)
+{
+   png_debug(1, "in png_set_user_transform_info\n");
+#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+   png_ptr->user_transform_ptr = user_transform_ptr;
+   png_ptr->user_transform_depth = (png_byte)user_transform_depth;
+   png_ptr->user_transform_channels = (png_byte)user_transform_channels;
+#else
+   if(user_transform_ptr || user_transform_depth || user_transform_channels)
+      png_warning(png_ptr,
+        "This version of libpng does not support user transform info");
+#endif
+}
+#endif
+
+/* This function returns a pointer to the user_transform_ptr associated with
+ * the user transform functions.  The application should free any memory
+ * associated with this pointer before png_write_destroy and png_read_destroy
+ * are called.
+ */
+png_voidp PNGAPI
+png_get_user_transform_ptr(png_structp png_ptr)
+{
+#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+   return ((png_voidp)png_ptr->user_transform_ptr);
+#else
+   if(png_ptr)
+     return (NULL);
+   return (NULL);
+#endif
+}
diff --git a/gs/libpng/pngvcrd.c b/gs/libpng/pngvcrd.c
new file mode 100644
index 000000000..940a7fc0f
--- /dev/null
+++ b/gs/libpng/pngvcrd.c
@@ -0,0 +1,3903 @@
+/* pngvcrd.c - mixed C/assembler version of utilities to read a PNG file
+ *
+ * For Intel x86 CPU and Microsoft Visual C++ compiler
+ *
+ * libpng version 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * Copyright (c) 1998, Intel Corporation
+ *
+ * Contributed by Nirav Chhatrapati, Intel Corporation, 1998
+ * Interface to libpng contributed by Gilles Vollant, 1999
+ *
+ *
+ * In png_do_read_interlace() in libpng versions 1.0.3a through 1.0.4d,
+ * a sign error in the post-MMX cleanup code for each pixel_depth resulted
+ * in bad pixels at the beginning of some rows of some images, and also
+ * (due to out-of-range memory reads and writes) caused heap corruption
+ * when compiled with MSVC 6.0.  The error was fixed in version 1.0.4e.
+ *
+ * [png_read_filter_row_mmx_avg() bpp == 2 bugfix, GRR 20000916]
+ *
+ * [runtime MMX configuration, GRR 20010102]
+ *
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && defined(PNG_USE_PNGVCRD)
+
+static int mmx_supported=2;
+
+
+int PNGAPI
+png_mmx_support(void)
+{
+  int mmx_supported_local = 0;
+  _asm {
+    push ebx          //CPUID will trash these
+    push ecx
+    push edx
+
+    pushfd            //Save Eflag to stack
+    pop eax           //Get Eflag from stack into eax
+    mov ecx, eax      //Make another copy of Eflag in ecx
+    xor eax, 0x200000 //Toggle ID bit in Eflag [i.e. bit(21)]
+    push eax          //Save modified Eflag back to stack
+
+    popfd             //Restored modified value back to Eflag reg
+    pushfd            //Save Eflag to stack
+    pop eax           //Get Eflag from stack
+    push ecx          // save original Eflag to stack
+    popfd             // restore original Eflag
+    xor eax, ecx      //Compare the new Eflag with the original Eflag
+    jz NOT_SUPPORTED  //If the same, CPUID instruction is not supported,
+                      //skip following instructions and jump to
+                      //NOT_SUPPORTED label
+
+    xor eax, eax      //Set eax to zero
+
+    _asm _emit 0x0f   //CPUID instruction  (two bytes opcode)
+    _asm _emit 0xa2
+
+    cmp eax, 1        //make sure eax return non-zero value
+    jl NOT_SUPPORTED  //If eax is zero, mmx not supported
+
+    xor eax, eax      //set eax to zero
+    inc eax           //Now increment eax to 1.  This instruction is
+                      //faster than the instruction "mov eax, 1"
+
+    _asm _emit 0x0f   //CPUID instruction
+    _asm _emit 0xa2
+
+    and edx, 0x00800000  //mask out all bits but mmx bit(24)
+    cmp edx, 0        // 0 = mmx not supported
+    jz  NOT_SUPPORTED // non-zero = Yes, mmx IS supported
+
+    mov  mmx_supported_local, 1  //set return value to 1
+
+NOT_SUPPORTED:
+    mov  eax, mmx_supported_local  //move return value to eax
+    pop edx          //CPUID trashed these
+    pop ecx
+    pop ebx
+  }
+
+  //mmx_supported_local=0; // test code for force don't support MMX
+  //printf("MMX : %u (1=MMX supported)\n",mmx_supported_local);
+
+  mmx_supported = mmx_supported_local;
+  return mmx_supported_local;
+}
+
+/* Combines the row recently read in with the previous row.
+   This routine takes care of alpha and transparency if requested.
+   This routine also handles the two methods of progressive display
+   of interlaced images, depending on the mask value.
+   The mask value describes which pixels are to be combined with
+   the row.  The pattern always repeats every 8 pixels, so just 8
+   bits are needed.  A one indicates the pixel is to be combined; a
+   zero indicates the pixel is to be skipped.  This is in addition
+   to any alpha or transparency value associated with the pixel.  If
+   you want all pixels to be combined, pass 0xff (255) in mask.  */
+
+/* Use this routine for x86 platform - uses faster MMX routine if machine
+   supports MMX */
+
+void /* PRIVATE */
+png_combine_row(png_structp png_ptr, png_bytep row, int mask)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   const int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+#endif
+
+   png_debug(1,"in png_combine_row_asm\n");
+
+   if (mmx_supported == 2) {
+#if !defined(PNG_1_0_X)
+       /* this should have happened in png_init_mmx_flags() already */
+       png_warning(png_ptr, "asm_flags may not have been initialized");
+#endif
+       png_mmx_support();
+   }
+
+   if (mask == 0xff)
+   {
+      png_memcpy(row, png_ptr->row_buf + 1,
+       (png_size_t)PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
+       png_ptr->width));
+   }
+   /* GRR:  add "else if (mask == 0)" case?
+    *       or does png_combine_row() not even get called in that case? */
+   else
+   {
+      switch (png_ptr->row_info.pixel_depth)
+      {
+         case 1:
+         {
+            png_bytep sp;
+            png_bytep dp;
+            int s_inc, s_start, s_end;
+            int m;
+            int shift;
+            png_uint_32 i;
+
+            sp = png_ptr->row_buf + 1;
+            dp = row;
+            m = 0x80;
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (png_ptr->transformations & PNG_PACKSWAP)
+            {
+                s_start = 0;
+                s_end = 7;
+                s_inc = 1;
+            }
+            else
+#endif
+            {
+                s_start = 7;
+                s_end = 0;
+                s_inc = -1;
+            }
+
+            shift = s_start;
+
+            for (i = 0; i < png_ptr->width; i++)
+            {
+               if (m & mask)
+               {
+                  int value;
+
+                  value = (*sp >> shift) & 0x1;
+                  *dp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff);
+                  *dp |= (png_byte)(value << shift);
+               }
+
+               if (shift == s_end)
+               {
+                  shift = s_start;
+                  sp++;
+                  dp++;
+               }
+               else
+                  shift += s_inc;
+
+               if (m == 1)
+                  m = 0x80;
+               else
+                  m >>= 1;
+            }
+            break;
+         }
+
+         case 2:
+         {
+            png_bytep sp;
+            png_bytep dp;
+            int s_start, s_end, s_inc;
+            int m;
+            int shift;
+            png_uint_32 i;
+            int value;
+
+            sp = png_ptr->row_buf + 1;
+            dp = row;
+            m = 0x80;
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (png_ptr->transformations & PNG_PACKSWAP)
+            {
+               s_start = 0;
+               s_end = 6;
+               s_inc = 2;
+            }
+            else
+#endif
+            {
+               s_start = 6;
+               s_end = 0;
+               s_inc = -2;
+            }
+
+            shift = s_start;
+
+            for (i = 0; i < png_ptr->width; i++)
+            {
+               if (m & mask)
+               {
+                  value = (*sp >> shift) & 0x3;
+                  *dp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
+                  *dp |= (png_byte)(value << shift);
+               }
+
+               if (shift == s_end)
+               {
+                  shift = s_start;
+                  sp++;
+                  dp++;
+               }
+               else
+                  shift += s_inc;
+               if (m == 1)
+                  m = 0x80;
+               else
+                  m >>= 1;
+            }
+            break;
+         }
+
+         case 4:
+         {
+            png_bytep sp;
+            png_bytep dp;
+            int s_start, s_end, s_inc;
+            int m;
+            int shift;
+            png_uint_32 i;
+            int value;
+
+            sp = png_ptr->row_buf + 1;
+            dp = row;
+            m = 0x80;
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (png_ptr->transformations & PNG_PACKSWAP)
+            {
+               s_start = 0;
+               s_end = 4;
+               s_inc = 4;
+            }
+            else
+#endif
+            {
+               s_start = 4;
+               s_end = 0;
+               s_inc = -4;
+            }
+            shift = s_start;
+
+            for (i = 0; i < png_ptr->width; i++)
+            {
+               if (m & mask)
+               {
+                  value = (*sp >> shift) & 0xf;
+                  *dp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
+                  *dp |= (png_byte)(value << shift);
+               }
+
+               if (shift == s_end)
+               {
+                  shift = s_start;
+                  sp++;
+                  dp++;
+               }
+               else
+                  shift += s_inc;
+               if (m == 1)
+                  m = 0x80;
+               else
+                  m >>= 1;
+            }
+            break;
+         }
+
+         case 8:
+         {
+            png_bytep srcptr;
+            png_bytep dstptr;
+            png_uint_32 len;
+            int m;
+            int diff, unmask;
+
+            __int64 mask0=0x0102040810204080;
+
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)
+                /* && mmx_supported */ )
+#else
+            if (mmx_supported)
+#endif
+            {
+               srcptr = png_ptr->row_buf + 1;
+               dstptr = row;
+               m = 0x80;
+               unmask = ~mask;
+               len  = png_ptr->width &~7;  //reduce to multiple of 8
+               diff = png_ptr->width & 7;  //amount lost
+
+               _asm
+               {
+                  movd       mm7, unmask   //load bit pattern
+                  psubb      mm6,mm6       //zero mm6
+                  punpcklbw  mm7,mm7
+                  punpcklwd  mm7,mm7
+                  punpckldq  mm7,mm7       //fill register with 8 masks
+
+                  movq       mm0,mask0
+
+                  pand       mm0,mm7       //nonzero if keep byte
+                  pcmpeqb    mm0,mm6       //zeros->1s, v versa
+
+                  mov        ecx,len       //load length of line (pixels)
+                  mov        esi,srcptr    //load source
+                  mov        ebx,dstptr    //load dest
+                  cmp        ecx,0         //lcr
+                  je         mainloop8end
+
+mainloop8:
+                  movq       mm4,[esi]
+                  pand       mm4,mm0
+                  movq       mm6,mm0
+                  pandn      mm6,[ebx]
+                  por        mm4,mm6
+                  movq       [ebx],mm4
+
+                  add        esi,8         //inc by 8 bytes processed
+                  add        ebx,8
+                  sub        ecx,8         //dec by 8 pixels processed
+
+                  ja         mainloop8
+mainloop8end:
+
+                  mov        ecx,diff
+                  cmp        ecx,0
+                  jz         end8
+
+                  mov        edx,mask
+                  sal        edx,24        //make low byte the high byte
+
+secondloop8:
+                  sal        edx,1         //move high bit to CF
+                  jnc        skip8         //if CF = 0
+                  mov        al,[esi]
+                  mov        [ebx],al
+skip8:
+                  inc        esi
+                  inc        ebx
+
+                  dec        ecx
+                  jnz        secondloop8
+end8:
+                  emms
+               }
+            }
+            else /* mmx not supported - use modified C routine */
+            {
+               register unsigned int incr1, initial_val, final_val;
+               png_size_t pixel_bytes;
+               png_uint_32 i;
+               register int disp = png_pass_inc[png_ptr->pass];
+               int offset_table[7] = {0, 4, 0, 2, 0, 1, 0};
+
+               pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
+               srcptr = png_ptr->row_buf + 1 + offset_table[png_ptr->pass]*
+                  pixel_bytes;
+               dstptr = row + offset_table[png_ptr->pass]*pixel_bytes;
+               initial_val = offset_table[png_ptr->pass]*pixel_bytes;
+               final_val = png_ptr->width*pixel_bytes;
+               incr1 = (disp)*pixel_bytes;
+               for (i = initial_val; i < final_val; i += incr1)
+               {
+                  png_memcpy(dstptr, srcptr, pixel_bytes);
+                  srcptr += incr1;
+                  dstptr += incr1;
+               }
+            } /* end of else */
+
+            break;
+         }       // end 8 bpp
+
+         case 16:
+         {
+            png_bytep srcptr;
+            png_bytep dstptr;
+            png_uint_32 len;
+            int unmask, diff;
+            __int64 mask1=0x0101020204040808,
+                    mask0=0x1010202040408080;
+
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)
+                /* && mmx_supported */ )
+#else
+            if (mmx_supported)
+#endif
+            {
+               srcptr = png_ptr->row_buf + 1;
+               dstptr = row;
+
+               unmask = ~mask;
+               len     = (png_ptr->width)&~7;
+               diff = (png_ptr->width)&7;
+               _asm
+               {
+                  movd       mm7, unmask       //load bit pattern
+                  psubb      mm6,mm6           //zero mm6
+                  punpcklbw  mm7,mm7
+                  punpcklwd  mm7,mm7
+                  punpckldq  mm7,mm7           //fill register with 8 masks
+
+                  movq       mm0,mask0
+                  movq       mm1,mask1
+
+                  pand       mm0,mm7
+                  pand       mm1,mm7
+
+                  pcmpeqb    mm0,mm6
+                  pcmpeqb    mm1,mm6
+
+                  mov        ecx,len           //load length of line
+                  mov        esi,srcptr        //load source
+                  mov        ebx,dstptr        //load dest
+                  cmp        ecx,0             //lcr
+                  jz         mainloop16end
+
+mainloop16:
+                  movq       mm4,[esi]
+                  pand       mm4,mm0
+                  movq       mm6,mm0
+                  movq       mm7,[ebx]
+                  pandn      mm6,mm7
+                  por        mm4,mm6
+                  movq       [ebx],mm4
+
+                  movq       mm5,[esi+8]
+                  pand       mm5,mm1
+                  movq       mm7,mm1
+                  movq       mm6,[ebx+8]
+                  pandn      mm7,mm6
+                  por        mm5,mm7
+                  movq       [ebx+8],mm5
+
+                  add        esi,16            //inc by 16 bytes processed
+                  add        ebx,16
+                  sub        ecx,8             //dec by 8 pixels processed
+
+                  ja         mainloop16
+
+mainloop16end:
+                  mov        ecx,diff
+                  cmp        ecx,0
+                  jz         end16
+
+                  mov        edx,mask
+                  sal        edx,24            //make low byte the high byte
+secondloop16:
+                  sal        edx,1             //move high bit to CF
+                  jnc        skip16            //if CF = 0
+                  mov        ax,[esi]
+                  mov        [ebx],ax
+skip16:
+                  add        esi,2
+                  add        ebx,2
+
+                  dec        ecx
+                  jnz        secondloop16
+end16:
+                  emms
+               }
+            }
+            else /* mmx not supported - use modified C routine */
+            {
+               register unsigned int incr1, initial_val, final_val;
+               png_size_t pixel_bytes;
+               png_uint_32 i;
+               register int disp = png_pass_inc[png_ptr->pass];
+               int offset_table[7] = {0, 4, 0, 2, 0, 1, 0};
+
+               pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
+               srcptr = png_ptr->row_buf + 1 + offset_table[png_ptr->pass]*
+                  pixel_bytes;
+               dstptr = row + offset_table[png_ptr->pass]*pixel_bytes;
+               initial_val = offset_table[png_ptr->pass]*pixel_bytes;
+               final_val = png_ptr->width*pixel_bytes;
+               incr1 = (disp)*pixel_bytes;
+               for (i = initial_val; i < final_val; i += incr1)
+               {
+                  png_memcpy(dstptr, srcptr, pixel_bytes);
+                  srcptr += incr1;
+                  dstptr += incr1;
+               }
+            } /* end of else */
+
+            break;
+         }       // end 16 bpp
+
+         case 24:
+         {
+            png_bytep srcptr;
+            png_bytep dstptr;
+            png_uint_32 len;
+            int unmask, diff;
+
+            __int64 mask2=0x0101010202020404,  //24bpp
+                    mask1=0x0408080810101020,
+                    mask0=0x2020404040808080;
+
+            srcptr = png_ptr->row_buf + 1;
+            dstptr = row;
+
+            unmask = ~mask;
+            len     = (png_ptr->width)&~7;
+            diff = (png_ptr->width)&7;
+
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)
+                /* && mmx_supported */ )
+#else
+            if (mmx_supported)
+#endif
+            {
+               _asm
+               {
+                  movd       mm7, unmask       //load bit pattern
+                  psubb      mm6,mm6           //zero mm6
+                  punpcklbw  mm7,mm7
+                  punpcklwd  mm7,mm7
+                  punpckldq  mm7,mm7           //fill register with 8 masks
+
+                  movq       mm0,mask0
+                  movq       mm1,mask1
+                  movq       mm2,mask2
+
+                  pand       mm0,mm7
+                  pand       mm1,mm7
+                  pand       mm2,mm7
+
+                  pcmpeqb    mm0,mm6
+                  pcmpeqb    mm1,mm6
+                  pcmpeqb    mm2,mm6
+
+                  mov        ecx,len           //load length of line
+                  mov        esi,srcptr        //load source
+                  mov        ebx,dstptr        //load dest
+                  cmp        ecx,0
+                  jz         mainloop24end
+
+mainloop24:
+                  movq       mm4,[esi]
+                  pand       mm4,mm0
+                  movq       mm6,mm0
+                  movq       mm7,[ebx]
+                  pandn      mm6,mm7
+                  por        mm4,mm6
+                  movq       [ebx],mm4
+
+
+                  movq       mm5,[esi+8]
+                  pand       mm5,mm1
+                  movq       mm7,mm1
+                  movq       mm6,[ebx+8]
+                  pandn      mm7,mm6
+                  por        mm5,mm7
+                  movq       [ebx+8],mm5
+
+                  movq       mm6,[esi+16]
+                  pand       mm6,mm2
+                  movq       mm4,mm2
+                  movq       mm7,[ebx+16]
+                  pandn      mm4,mm7
+                  por        mm6,mm4
+                  movq       [ebx+16],mm6
+
+                  add        esi,24            //inc by 24 bytes processed
+                  add        ebx,24
+                  sub        ecx,8             //dec by 8 pixels processed
+
+                  ja         mainloop24
+
+mainloop24end:
+                  mov        ecx,diff
+                  cmp        ecx,0
+                  jz         end24
+
+                  mov        edx,mask
+                  sal        edx,24            //make low byte the high byte
+secondloop24:
+                  sal        edx,1             //move high bit to CF
+                  jnc        skip24            //if CF = 0
+                  mov        ax,[esi]
+                  mov        [ebx],ax
+                  xor        eax,eax
+                  mov        al,[esi+2]
+                  mov        [ebx+2],al
+skip24:
+                  add        esi,3
+                  add        ebx,3
+
+                  dec        ecx
+                  jnz        secondloop24
+
+end24:
+                  emms
+               }
+            }
+            else /* mmx not supported - use modified C routine */
+            {
+               register unsigned int incr1, initial_val, final_val;
+               png_size_t pixel_bytes;
+               png_uint_32 i;
+               register int disp = png_pass_inc[png_ptr->pass];
+               int offset_table[7] = {0, 4, 0, 2, 0, 1, 0};
+
+               pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
+               srcptr = png_ptr->row_buf + 1 + offset_table[png_ptr->pass]*
+                  pixel_bytes;
+               dstptr = row + offset_table[png_ptr->pass]*pixel_bytes;
+               initial_val = offset_table[png_ptr->pass]*pixel_bytes;
+               final_val = png_ptr->width*pixel_bytes;
+               incr1 = (disp)*pixel_bytes;
+               for (i = initial_val; i < final_val; i += incr1)
+               {
+                  png_memcpy(dstptr, srcptr, pixel_bytes);
+                  srcptr += incr1;
+                  dstptr += incr1;
+               }
+            } /* end of else */
+
+            break;
+         }       // end 24 bpp
+
+         case 32:
+         {
+            png_bytep srcptr;
+            png_bytep dstptr;
+            png_uint_32 len;
+            int unmask, diff;
+
+            __int64 mask3=0x0101010102020202,  //32bpp
+                    mask2=0x0404040408080808,
+                    mask1=0x1010101020202020,
+                    mask0=0x4040404080808080;
+
+            srcptr = png_ptr->row_buf + 1;
+            dstptr = row;
+
+            unmask = ~mask;
+            len     = (png_ptr->width)&~7;
+            diff = (png_ptr->width)&7;
+
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)
+                /* && mmx_supported */ )
+#else
+            if (mmx_supported)
+#endif
+            {
+               _asm
+               {
+                  movd       mm7, unmask       //load bit pattern
+                  psubb      mm6,mm6           //zero mm6
+                  punpcklbw  mm7,mm7
+                  punpcklwd  mm7,mm7
+                  punpckldq  mm7,mm7           //fill register with 8 masks
+
+                  movq       mm0,mask0
+                  movq       mm1,mask1
+                  movq       mm2,mask2
+                  movq       mm3,mask3
+
+                  pand       mm0,mm7
+                  pand       mm1,mm7
+                  pand       mm2,mm7
+                  pand       mm3,mm7
+
+                  pcmpeqb    mm0,mm6
+                  pcmpeqb    mm1,mm6
+                  pcmpeqb    mm2,mm6
+                  pcmpeqb    mm3,mm6
+
+                  mov        ecx,len           //load length of line
+                  mov        esi,srcptr        //load source
+                  mov        ebx,dstptr        //load dest
+
+                  cmp        ecx,0             //lcr
+                  jz         mainloop32end
+
+mainloop32:
+                  movq       mm4,[esi]
+                  pand       mm4,mm0
+                  movq       mm6,mm0
+                  movq       mm7,[ebx]
+                  pandn      mm6,mm7
+                  por        mm4,mm6
+                  movq       [ebx],mm4
+
+                  movq       mm5,[esi+8]
+                  pand       mm5,mm1
+                  movq       mm7,mm1
+                  movq       mm6,[ebx+8]
+                  pandn      mm7,mm6
+                  por        mm5,mm7
+                  movq       [ebx+8],mm5
+
+                  movq       mm6,[esi+16]
+                  pand       mm6,mm2
+                  movq       mm4,mm2
+                  movq       mm7,[ebx+16]
+                  pandn      mm4,mm7
+                  por        mm6,mm4
+                  movq       [ebx+16],mm6
+
+                  movq       mm7,[esi+24]
+                  pand       mm7,mm3
+                  movq       mm5,mm3
+                  movq       mm4,[ebx+24]
+                  pandn      mm5,mm4
+                  por        mm7,mm5
+                  movq       [ebx+24],mm7
+
+                  add        esi,32            //inc by 32 bytes processed
+                  add        ebx,32
+                  sub        ecx,8             //dec by 8 pixels processed
+
+                  ja         mainloop32
+
+mainloop32end:
+                  mov        ecx,diff
+                  cmp        ecx,0
+                  jz         end32
+
+                  mov        edx,mask
+                  sal        edx,24            //make low byte the high byte
+secondloop32:
+                  sal        edx,1             //move high bit to CF
+                  jnc        skip32            //if CF = 0
+                  mov        eax,[esi]
+                  mov        [ebx],eax
+skip32:
+                  add        esi,4
+                  add        ebx,4
+
+                  dec        ecx
+                  jnz        secondloop32
+
+end32:
+                  emms
+               }
+            }
+            else /* mmx _not supported - Use modified C routine */
+            {
+               register unsigned int incr1, initial_val, final_val;
+               png_size_t pixel_bytes;
+               png_uint_32 i;
+               register int disp = png_pass_inc[png_ptr->pass];
+               int offset_table[7] = {0, 4, 0, 2, 0, 1, 0};
+
+               pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
+               srcptr = png_ptr->row_buf + 1 + offset_table[png_ptr->pass]*
+                  pixel_bytes;
+               dstptr = row + offset_table[png_ptr->pass]*pixel_bytes;
+               initial_val = offset_table[png_ptr->pass]*pixel_bytes;
+               final_val = png_ptr->width*pixel_bytes;
+               incr1 = (disp)*pixel_bytes;
+               for (i = initial_val; i < final_val; i += incr1)
+               {
+                  png_memcpy(dstptr, srcptr, pixel_bytes);
+                  srcptr += incr1;
+                  dstptr += incr1;
+               }
+            } /* end of else */
+
+            break;
+         }       // end 32 bpp
+
+         case 48:
+         {
+            png_bytep srcptr;
+            png_bytep dstptr;
+            png_uint_32 len;
+            int unmask, diff;
+
+            __int64 mask5=0x0101010101010202,
+                    mask4=0x0202020204040404,
+                    mask3=0x0404080808080808,
+                    mask2=0x1010101010102020,
+                    mask1=0x2020202040404040,
+                    mask0=0x4040808080808080;
+
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)
+                /* && mmx_supported */ )
+#else
+            if (mmx_supported)
+#endif
+            {
+               srcptr = png_ptr->row_buf + 1;
+               dstptr = row;
+
+               unmask = ~mask;
+               len     = (png_ptr->width)&~7;
+               diff = (png_ptr->width)&7;
+               _asm
+               {
+                  movd       mm7, unmask       //load bit pattern
+                  psubb      mm6,mm6           //zero mm6
+                  punpcklbw  mm7,mm7
+                  punpcklwd  mm7,mm7
+                  punpckldq  mm7,mm7           //fill register with 8 masks
+
+                  movq       mm0,mask0
+                  movq       mm1,mask1
+                  movq       mm2,mask2
+                  movq       mm3,mask3
+                  movq       mm4,mask4
+                  movq       mm5,mask5
+
+                  pand       mm0,mm7
+                  pand       mm1,mm7
+                  pand       mm2,mm7
+                  pand       mm3,mm7
+                  pand       mm4,mm7
+                  pand       mm5,mm7
+
+                  pcmpeqb    mm0,mm6
+                  pcmpeqb    mm1,mm6
+                  pcmpeqb    mm2,mm6
+                  pcmpeqb    mm3,mm6
+                  pcmpeqb    mm4,mm6
+                  pcmpeqb    mm5,mm6
+
+                  mov        ecx,len           //load length of line
+                  mov        esi,srcptr        //load source
+                  mov        ebx,dstptr        //load dest
+
+                  cmp        ecx,0
+                  jz         mainloop48end
+
+mainloop48:
+                  movq       mm7,[esi]
+                  pand       mm7,mm0
+                  movq       mm6,mm0
+                  pandn      mm6,[ebx]
+                  por        mm7,mm6
+                  movq       [ebx],mm7
+
+                  movq       mm6,[esi+8]
+                  pand       mm6,mm1
+                  movq       mm7,mm1
+                  pandn      mm7,[ebx+8]
+                  por        mm6,mm7
+                  movq       [ebx+8],mm6
+
+                  movq       mm6,[esi+16]
+                  pand       mm6,mm2
+                  movq       mm7,mm2
+                  pandn      mm7,[ebx+16]
+                  por        mm6,mm7
+                  movq       [ebx+16],mm6
+
+                  movq       mm7,[esi+24]
+                  pand       mm7,mm3
+                  movq       mm6,mm3
+                  pandn      mm6,[ebx+24]
+                  por        mm7,mm6
+                  movq       [ebx+24],mm7
+
+                  movq       mm6,[esi+32]
+                  pand       mm6,mm4
+                  movq       mm7,mm4
+                  pandn      mm7,[ebx+32]
+                  por        mm6,mm7
+                  movq       [ebx+32],mm6
+
+                  movq       mm7,[esi+40]
+                  pand       mm7,mm5
+                  movq       mm6,mm5
+                  pandn      mm6,[ebx+40]
+                  por        mm7,mm6
+                  movq       [ebx+40],mm7
+
+                  add        esi,48            //inc by 32 bytes processed
+                  add        ebx,48
+                  sub        ecx,8             //dec by 8 pixels processed
+
+                  ja         mainloop48
+mainloop48end:
+
+                  mov        ecx,diff
+                  cmp        ecx,0
+                  jz         end48
+
+                  mov        edx,mask
+                  sal        edx,24            //make low byte the high byte
+
+secondloop48:
+                  sal        edx,1             //move high bit to CF
+                  jnc        skip48            //if CF = 0
+                  mov        eax,[esi]
+                  mov        [ebx],eax
+skip48:
+                  add        esi,4
+                  add        ebx,4
+
+                  dec        ecx
+                  jnz        secondloop48
+
+end48:
+                  emms
+               }
+            }
+            else /* mmx _not supported - Use modified C routine */
+            {
+               register unsigned int incr1, initial_val, final_val;
+               png_size_t pixel_bytes;
+               png_uint_32 i;
+               register int disp = png_pass_inc[png_ptr->pass];
+               int offset_table[7] = {0, 4, 0, 2, 0, 1, 0};
+
+               pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
+               srcptr = png_ptr->row_buf + 1 + offset_table[png_ptr->pass]*
+                  pixel_bytes;
+               dstptr = row + offset_table[png_ptr->pass]*pixel_bytes;
+               initial_val = offset_table[png_ptr->pass]*pixel_bytes;
+               final_val = png_ptr->width*pixel_bytes;
+               incr1 = (disp)*pixel_bytes;
+               for (i = initial_val; i < final_val; i += incr1)
+               {
+                  png_memcpy(dstptr, srcptr, pixel_bytes);
+                  srcptr += incr1;
+                  dstptr += incr1;
+               }
+            } /* end of else */
+
+            break;
+         }       // end 48 bpp
+
+         default:
+         {
+            png_bytep sptr;
+            png_bytep dp;
+            png_size_t pixel_bytes;
+            int offset_table[7] = {0, 4, 0, 2, 0, 1, 0};
+            unsigned int i;
+            register int disp = png_pass_inc[png_ptr->pass];  // get the offset
+            register unsigned int incr1, initial_val, final_val;
+
+            pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
+            sptr = png_ptr->row_buf + 1 + offset_table[png_ptr->pass]*
+               pixel_bytes;
+            dp = row + offset_table[png_ptr->pass]*pixel_bytes;
+            initial_val = offset_table[png_ptr->pass]*pixel_bytes;
+            final_val = png_ptr->width*pixel_bytes;
+            incr1 = (disp)*pixel_bytes;
+            for (i = initial_val; i < final_val; i += incr1)
+            {
+               png_memcpy(dp, sptr, pixel_bytes);
+               sptr += incr1;
+               dp += incr1;
+            }
+            break;
+         }
+      } /* end switch (png_ptr->row_info.pixel_depth) */
+   } /* end if (non-trivial mask) */
+
+} /* end png_combine_row() */
+
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+
+void /* PRIVATE */
+png_do_read_interlace(png_structp png_ptr)
+{
+   png_row_infop row_info = &(png_ptr->row_info);
+   png_bytep row = png_ptr->row_buf + 1;
+   int pass = png_ptr->pass;
+   png_uint_32 transformations = png_ptr->transformations;
+#ifdef PNG_USE_LOCAL_ARRAYS
+   const int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+#endif
+
+   png_debug(1,"in png_do_read_interlace\n");
+
+   if (mmx_supported == 2) {
+#if !defined(PNG_1_0_X)
+       /* this should have happened in png_init_mmx_flags() already */
+       png_warning(png_ptr, "asm_flags may not have been initialized");
+#endif
+       png_mmx_support();
+   }
+
+   if (row != NULL && row_info != NULL)
+   {
+      png_uint_32 final_width;
+
+      final_width = row_info->width * png_pass_inc[pass];
+
+      switch (row_info->pixel_depth)
+      {
+         case 1:
+         {
+            png_bytep sp, dp;
+            int sshift, dshift;
+            int s_start, s_end, s_inc;
+            png_byte v;
+            png_uint_32 i;
+            int j;
+
+            sp = row + (png_size_t)((row_info->width - 1) >> 3);
+            dp = row + (png_size_t)((final_width - 1) >> 3);
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (transformations & PNG_PACKSWAP)
+            {
+               sshift = (int)((row_info->width + 7) & 7);
+               dshift = (int)((final_width + 7) & 7);
+               s_start = 7;
+               s_end = 0;
+               s_inc = -1;
+            }
+            else
+#endif
+            {
+               sshift = 7 - (int)((row_info->width + 7) & 7);
+               dshift = 7 - (int)((final_width + 7) & 7);
+               s_start = 0;
+               s_end = 7;
+               s_inc = 1;
+            }
+
+            for (i = row_info->width; i; i--)
+            {
+               v = (png_byte)((*sp >> sshift) & 0x1);
+               for (j = 0; j < png_pass_inc[pass]; j++)
+               {
+                  *dp &= (png_byte)((0x7f7f >> (7 - dshift)) & 0xff);
+                  *dp |= (png_byte)(v << dshift);
+                  if (dshift == s_end)
+                  {
+                     dshift = s_start;
+                     dp--;
+                  }
+                  else
+                     dshift += s_inc;
+               }
+               if (sshift == s_end)
+               {
+                  sshift = s_start;
+                  sp--;
+               }
+               else
+                  sshift += s_inc;
+            }
+            break;
+         }
+
+         case 2:
+         {
+            png_bytep sp, dp;
+            int sshift, dshift;
+            int s_start, s_end, s_inc;
+            png_uint_32 i;
+
+            sp = row + (png_size_t)((row_info->width - 1) >> 2);
+            dp = row + (png_size_t)((final_width - 1) >> 2);
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (transformations & PNG_PACKSWAP)
+            {
+               sshift = (png_size_t)(((row_info->width + 3) & 3) << 1);
+               dshift = (png_size_t)(((final_width + 3) & 3) << 1);
+               s_start = 6;
+               s_end = 0;
+               s_inc = -2;
+            }
+            else
+#endif
+            {
+               sshift = (png_size_t)((3 - ((row_info->width + 3) & 3)) << 1);
+               dshift = (png_size_t)((3 - ((final_width + 3) & 3)) << 1);
+               s_start = 0;
+               s_end = 6;
+               s_inc = 2;
+            }
+
+            for (i = row_info->width; i; i--)
+            {
+               png_byte v;
+               int j;
+
+               v = (png_byte)((*sp >> sshift) & 0x3);
+               for (j = 0; j < png_pass_inc[pass]; j++)
+               {
+                  *dp &= (png_byte)((0x3f3f >> (6 - dshift)) & 0xff);
+                  *dp |= (png_byte)(v << dshift);
+                  if (dshift == s_end)
+                  {
+                     dshift = s_start;
+                     dp--;
+                  }
+                  else
+                     dshift += s_inc;
+               }
+               if (sshift == s_end)
+               {
+                  sshift = s_start;
+                  sp--;
+               }
+               else
+                  sshift += s_inc;
+            }
+            break;
+         }
+
+         case 4:
+         {
+            png_bytep sp, dp;
+            int sshift, dshift;
+            int s_start, s_end, s_inc;
+            png_uint_32 i;
+
+            sp = row + (png_size_t)((row_info->width - 1) >> 1);
+            dp = row + (png_size_t)((final_width - 1) >> 1);
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+            if (transformations & PNG_PACKSWAP)
+            {
+               sshift = (png_size_t)(((row_info->width + 1) & 1) << 2);
+               dshift = (png_size_t)(((final_width + 1) & 1) << 2);
+               s_start = 4;
+               s_end = 0;
+               s_inc = -4;
+            }
+            else
+#endif
+            {
+               sshift = (png_size_t)((1 - ((row_info->width + 1) & 1)) << 2);
+               dshift = (png_size_t)((1 - ((final_width + 1) & 1)) << 2);
+               s_start = 0;
+               s_end = 4;
+               s_inc = 4;
+            }
+
+            for (i = row_info->width; i; i--)
+            {
+               png_byte v;
+               int j;
+
+               v = (png_byte)((*sp >> sshift) & 0xf);
+               for (j = 0; j < png_pass_inc[pass]; j++)
+               {
+                  *dp &= (png_byte)((0xf0f >> (4 - dshift)) & 0xff);
+                  *dp |= (png_byte)(v << dshift);
+                  if (dshift == s_end)
+                  {
+                     dshift = s_start;
+                     dp--;
+                  }
+                  else
+                     dshift += s_inc;
+               }
+               if (sshift == s_end)
+               {
+                  sshift = s_start;
+                  sp--;
+               }
+               else
+                  sshift += s_inc;
+            }
+            break;
+         }
+
+         default:         // This is the place where the routine is modified
+         {
+            __int64 const4 = 0x0000000000FFFFFF;
+            // __int64 const5 = 0x000000FFFFFF0000;  // unused...
+            __int64 const6 = 0x00000000000000FF;
+            png_bytep sptr, dp;
+            png_uint_32 i;
+            png_size_t pixel_bytes;
+            int width = row_info->width;
+
+            pixel_bytes = (row_info->pixel_depth >> 3);
+
+            sptr = row + (width - 1) * pixel_bytes;
+            dp = row + (final_width - 1) * pixel_bytes;
+            // New code by Nirav Chhatrapati - Intel Corporation
+            // sign fix by GRR
+            // NOTE:  there is NO MMX code for 48-bit and 64-bit images
+
+            // use MMX routine if machine supports it
+#if !defined(PNG_1_0_X)
+            if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_INTERLACE)
+                /* && mmx_supported */ )
+#else
+            if (mmx_supported)
+#endif
+            {
+               if (pixel_bytes == 3)
+               {
+                  if (((pass == 0) || (pass == 1)) && width)
+                  {
+                     _asm
+                     {
+                        mov esi, sptr
+                        mov edi, dp
+                        mov ecx, width
+                        sub edi, 21   // (png_pass_inc[pass] - 1)*pixel_bytes
+loop_pass0:
+                        movd mm0, [esi]     ; X X X X X v2 v1 v0
+                        pand mm0, const4    ; 0 0 0 0 0 v2 v1 v0
+                        movq mm1, mm0       ; 0 0 0 0 0 v2 v1 v0
+                        psllq mm0, 16       ; 0 0 0 v2 v1 v0 0 0
+                        movq mm2, mm0       ; 0 0 0 v2 v1 v0 0 0
+                        psllq mm0, 24       ; v2 v1 v0 0 0 0 0 0
+                        psrlq mm1, 8        ; 0 0 0 0 0 0 v2 v1
+                        por mm0, mm2        ; v2 v1 v0 v2 v1 v0 0 0
+                        por mm0, mm1        ; v2 v1 v0 v2 v1 v0 v2 v1
+                        movq mm3, mm0       ; v2 v1 v0 v2 v1 v0 v2 v1
+                        psllq mm0, 16       ; v0 v2 v1 v0 v2 v1 0 0
+                        movq mm4, mm3       ; v2 v1 v0 v2 v1 v0 v2 v1
+                        punpckhdq mm3, mm0  ; v0 v2 v1 v0 v2 v1 v0 v2
+                        movq [edi+16] , mm4
+                        psrlq mm0, 32       ; 0 0 0 0 v0 v2 v1 v0
+                        movq [edi+8] , mm3
+                        punpckldq mm0, mm4  ; v1 v0 v2 v1 v0 v2 v1 v0
+                        sub esi, 3
+                        movq [edi], mm0
+                        sub edi, 24
+                        //sub esi, 3
+                        dec ecx
+                        jnz loop_pass0
+                        EMMS
+                     }
+                  }
+                  else if (((pass == 2) || (pass == 3)) && width)
+                  {
+                     _asm
+                     {
+                        mov esi, sptr
+                        mov edi, dp
+                        mov ecx, width
+                        sub edi, 9   // (png_pass_inc[pass] - 1)*pixel_bytes
+loop_pass2:
+                        movd mm0, [esi]     ; X X X X X v2 v1 v0
+                        pand mm0, const4    ; 0 0 0 0 0 v2 v1 v0
+                        movq mm1, mm0       ; 0 0 0 0 0 v2 v1 v0
+                        psllq mm0, 16       ; 0 0 0 v2 v1 v0 0 0
+                        movq mm2, mm0       ; 0 0 0 v2 v1 v0 0 0
+                        psllq mm0, 24       ; v2 v1 v0 0 0 0 0 0
+                        psrlq mm1, 8        ; 0 0 0 0 0 0 v2 v1
+                        por mm0, mm2        ; v2 v1 v0 v2 v1 v0 0 0
+                        por mm0, mm1        ; v2 v1 v0 v2 v1 v0 v2 v1
+                        movq [edi+4], mm0   ; move to memory
+                        psrlq mm0, 16       ; 0 0 v2 v1 v0 v2 v1 v0
+                        movd [edi], mm0     ; move to memory
+                        sub esi, 3
+                        sub edi, 12
+                        dec ecx
+                        jnz loop_pass2
+                        EMMS
+                     }
+                  }
+                  else if (width) /* && ((pass == 4) || (pass == 5)) */
+                  {
+                     int width_mmx = ((width >> 1) << 1) - 8;
+                     if (width_mmx < 0)
+                         width_mmx = 0;
+                     width -= width_mmx;        // 8 or 9 pix, 24 or 27 bytes
+                     if (width_mmx)
+                     {
+                        _asm
+                        {
+                           mov esi, sptr
+                           mov edi, dp
+                           mov ecx, width_mmx
+                           sub esi, 3
+                           sub edi, 9
+loop_pass4:
+                           movq mm0, [esi]     ; X X v2 v1 v0 v5 v4 v3
+                           movq mm7, mm0       ; X X v2 v1 v0 v5 v4 v3
+                           movq mm6, mm0       ; X X v2 v1 v0 v5 v4 v3
+                           psllq mm0, 24       ; v1 v0 v5 v4 v3 0 0 0
+                           pand mm7, const4    ; 0 0 0 0 0 v5 v4 v3
+                           psrlq mm6, 24       ; 0 0 0 X X v2 v1 v0
+                           por mm0, mm7        ; v1 v0 v5 v4 v3 v5 v4 v3
+                           movq mm5, mm6       ; 0 0 0 X X v2 v1 v0
+                           psllq mm6, 8        ; 0 0 X X v2 v1 v0 0
+                           movq [edi], mm0     ; move quad to memory
+                           psrlq mm5, 16       ; 0 0 0 0 0 X X v2
+                           pand mm5, const6    ; 0 0 0 0 0 0 0 v2
+                           por mm6, mm5        ; 0 0 X X v2 v1 v0 v2
+                           movd [edi+8], mm6   ; move double to memory
+                           sub esi, 6
+                           sub edi, 12
+                           sub ecx, 2
+                           jnz loop_pass4
+                           EMMS
+                        }
+                     }
+
+                     sptr -= width_mmx*3;
+                     dp -= width_mmx*6;
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+
+                        png_memcpy(v, sptr, 3);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           png_memcpy(dp, v, 3);
+                           dp -= 3;
+                        }
+                        sptr -= 3;
+                     }
+                  }
+               } /* end of pixel_bytes == 3 */
+
+               else if (pixel_bytes == 1)
+               {
+                  if (((pass == 0) || (pass == 1)) && width)
+                  {
+                     int width_mmx = ((width >> 2) << 2);
+                     width -= width_mmx;
+                     if (width_mmx)
+                     {
+                        _asm
+                        {
+                           mov esi, sptr
+                           mov edi, dp
+                           mov ecx, width_mmx
+                           sub edi, 31
+                           sub esi, 3
+loop1_pass0:
+                           movd mm0, [esi]     ; X X X X v0 v1 v2 v3
+                           movq mm1, mm0       ; X X X X v0 v1 v2 v3
+                           punpcklbw mm0, mm0  ; v0 v0 v1 v1 v2 v2 v3 v3
+                           movq mm2, mm0       ; v0 v0 v1 v1 v2 v2 v3 v3
+                           punpcklwd mm0, mm0  ; v2 v2 v2 v2 v3 v3 v3 v3
+                           movq mm3, mm0       ; v2 v2 v2 v2 v3 v3 v3 v3
+                           punpckldq mm0, mm0  ; v3 v3 v3 v3 v3 v3 v3 v3
+                           punpckhdq mm3, mm3  ; v2 v2 v2 v2 v2 v2 v2 v2
+                           movq [edi], mm0     ; move to memory v3
+                           punpckhwd mm2, mm2  ; v0 v0 v0 v0 v1 v1 v1 v1
+                           movq [edi+8], mm3   ; move to memory v2
+                           movq mm4, mm2       ; v0 v0 v0 v0 v1 v1 v1 v1
+                           punpckldq mm2, mm2  ; v1 v1 v1 v1 v1 v1 v1 v1
+                           punpckhdq mm4, mm4  ; v0 v0 v0 v0 v0 v0 v0 v0
+                           movq [edi+16], mm2  ; move to memory v1
+                           movq [edi+24], mm4  ; move to memory v0
+                           sub esi, 4
+                           sub edi, 32
+                           sub ecx, 4
+                           jnz loop1_pass0
+                           EMMS
+                        }
+                     }
+
+                     sptr -= width_mmx;
+                     dp -= width_mmx*8;
+                     for (i = width; i; i--)
+                     {
+                        int j;
+
+                       /* I simplified this part in version 1.0.4e
+                        * here and in several other instances where
+                        * pixel_bytes == 1  -- GR-P
+                        *
+                        * Original code:
+                        *
+                        * png_byte v[8];
+                        * png_memcpy(v, sptr, pixel_bytes);
+                        * for (j = 0; j < png_pass_inc[pass]; j++)
+                        * {
+                        *    png_memcpy(dp, v, pixel_bytes);
+                        *    dp -= pixel_bytes;
+                        * }
+                        * sptr -= pixel_bytes;
+                        *
+                        * Replacement code is in the next three lines:
+                        */
+
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                           *dp-- = *sptr;
+                        sptr--;
+                     }
+                  }
+                  else if (((pass == 2) || (pass == 3)) && width)
+                  {
+                     int width_mmx = ((width >> 2) << 2);
+                     width -= width_mmx;
+                     if (width_mmx)
+                     {
+                        _asm
+                        {
+                           mov esi, sptr
+                           mov edi, dp
+                           mov ecx, width_mmx
+                           sub edi, 15
+                           sub esi, 3
+loop1_pass2:
+                           movd mm0, [esi]     ; X X X X v0 v1 v2 v3
+                           punpcklbw mm0, mm0  ; v0 v0 v1 v1 v2 v2 v3 v3
+                           movq mm1, mm0       ; v0 v0 v1 v1 v2 v2 v3 v3
+                           punpcklwd mm0, mm0  ; v2 v2 v2 v2 v3 v3 v3 v3
+                           punpckhwd mm1, mm1  ; v0 v0 v0 v0 v1 v1 v1 v1
+                           movq [edi], mm0     ; move to memory v2 and v3
+                           sub esi, 4
+                           movq [edi+8], mm1   ; move to memory v1     and v0
+                           sub edi, 16
+                           sub ecx, 4
+                           jnz loop1_pass2
+                           EMMS
+                        }
+                     }
+
+                     sptr -= width_mmx;
+                     dp -= width_mmx*4;
+                     for (i = width; i; i--)
+                     {
+                        int j;
+
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           *dp-- = *sptr;
+                        }
+                        sptr --;
+                     }
+                  }
+                  else if (width) /* && ((pass == 4) || (pass == 5))) */
+                  {
+                     int width_mmx = ((width >> 3) << 3);
+                     width -= width_mmx;
+                     if (width_mmx)
+                     {
+                        _asm
+                        {
+                           mov esi, sptr
+                           mov edi, dp
+                           mov ecx, width_mmx
+                           sub edi, 15
+                           sub esi, 7
+loop1_pass4:
+                           movq mm0, [esi]     ; v0 v1 v2 v3 v4 v5 v6 v7
+                           movq mm1, mm0       ; v0 v1 v2 v3 v4 v5 v6 v7
+                           punpcklbw mm0, mm0  ; v4 v4 v5 v5 v6 v6 v7 v7
+                           //movq mm1, mm0     ; v0 v0 v1 v1 v2 v2 v3 v3
+                           punpckhbw mm1, mm1  ;v0 v0 v1 v1 v2 v2 v3 v3
+                           movq [edi+8], mm1   ; move to memory v0 v1 v2 and v3
+                           sub esi, 8
+                           movq [edi], mm0     ; move to memory v4 v5 v6 and v7
+                           //sub esi, 4
+                           sub edi, 16
+                           sub ecx, 8
+                           jnz loop1_pass4
+                           EMMS
+                        }
+                     }
+
+                     sptr -= width_mmx;
+                     dp -= width_mmx*2;
+                     for (i = width; i; i--)
+                     {
+                        int j;
+
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           *dp-- = *sptr;
+                        }
+                        sptr --;
+                     }
+                  }
+               } /* end of pixel_bytes == 1 */
+
+               else if (pixel_bytes == 2)
+               {
+                  if (((pass == 0) || (pass == 1)) && width)
+                  {
+                     int width_mmx = ((width >> 1) << 1);
+                     width -= width_mmx;
+                     if (width_mmx)
+                     {
+                        _asm
+                        {
+                           mov esi, sptr
+                           mov edi, dp
+                           mov ecx, width_mmx
+                           sub esi, 2
+                           sub edi, 30
+loop2_pass0:
+                           movd mm0, [esi]        ; X X X X v1 v0 v3 v2
+                           punpcklwd mm0, mm0     ; v1 v0 v1 v0 v3 v2 v3 v2
+                           movq mm1, mm0          ; v1 v0 v1 v0 v3 v2 v3 v2
+                           punpckldq mm0, mm0     ; v3 v2 v3 v2 v3 v2 v3 v2
+                           punpckhdq mm1, mm1     ; v1 v0 v1 v0 v1 v0 v1 v0
+                           movq [edi], mm0
+                           movq [edi + 8], mm0
+                           movq [edi + 16], mm1
+                           movq [edi + 24], mm1
+                           sub esi, 4
+                           sub edi, 32
+                           sub ecx, 2
+                           jnz loop2_pass0
+                           EMMS
+                        }
+                     }
+
+                     sptr -= (width_mmx*2 - 2);            // sign fixed
+                     dp -= (width_mmx*16 - 2);            // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 2;
+                        png_memcpy(v, sptr, 2);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 2;
+                           png_memcpy(dp, v, 2);
+                        }
+                     }
+                  }
+                  else if (((pass == 2) || (pass == 3)) && width)
+                  {
+                     int width_mmx = ((width >> 1) << 1) ;
+                     width -= width_mmx;
+                     if (width_mmx)
+                     {
+                        _asm
+                        {
+                           mov esi, sptr
+                           mov edi, dp
+                           mov ecx, width_mmx
+                           sub esi, 2
+                           sub edi, 14
+loop2_pass2:
+                           movd mm0, [esi]        ; X X X X v1 v0 v3 v2
+                           punpcklwd mm0, mm0     ; v1 v0 v1 v0 v3 v2 v3 v2
+                           movq mm1, mm0          ; v1 v0 v1 v0 v3 v2 v3 v2
+                           punpckldq mm0, mm0     ; v3 v2 v3 v2 v3 v2 v3 v2
+                           punpckhdq mm1, mm1     ; v1 v0 v1 v0 v1 v0 v1 v0
+                           movq [edi], mm0
+                           sub esi, 4
+                           movq [edi + 8], mm1
+                           //sub esi, 4
+                           sub edi, 16
+                           sub ecx, 2
+                           jnz loop2_pass2
+                           EMMS
+                        }
+                     }
+
+                     sptr -= (width_mmx*2 - 2);            // sign fixed
+                     dp -= (width_mmx*8 - 2);            // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 2;
+                        png_memcpy(v, sptr, 2);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 2;
+                           png_memcpy(dp, v, 2);
+                        }
+                     }
+                  }
+                  else if (width)  // pass == 4 or 5
+                  {
+                     int width_mmx = ((width >> 1) << 1) ;
+                     width -= width_mmx;
+                     if (width_mmx)
+                     {
+                        _asm
+                        {
+                           mov esi, sptr
+                           mov edi, dp
+                           mov ecx, width_mmx
+                           sub esi, 2
+                           sub edi, 6
+loop2_pass4:
+                           movd mm0, [esi]        ; X X X X v1 v0 v3 v2
+                           punpcklwd mm0, mm0     ; v1 v0 v1 v0 v3 v2 v3 v2
+                           sub esi, 4
+                           movq [edi], mm0
+                           sub edi, 8
+                           sub ecx, 2
+                           jnz loop2_pass4
+                           EMMS
+                        }
+                     }
+
+                     sptr -= (width_mmx*2 - 2);            // sign fixed
+                     dp -= (width_mmx*4 - 2);            // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 2;
+                        png_memcpy(v, sptr, 2);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 2;
+                           png_memcpy(dp, v, 2);
+                        }
+                     }
+                  }
+               } /* end of pixel_bytes == 2 */
+
+               else if (pixel_bytes == 4)
+               {
+                  if (((pass == 0) || (pass == 1)) && width)
+                  {
+                     int width_mmx = ((width >> 1) << 1) ;
+                     width -= width_mmx;
+                     if (width_mmx)
+                     {
+                        _asm
+                        {
+                           mov esi, sptr
+                           mov edi, dp
+                           mov ecx, width_mmx
+                           sub esi, 4
+                           sub edi, 60
+loop4_pass0:
+                           movq mm0, [esi]        ; v3 v2 v1 v0 v7 v6 v5 v4
+                           movq mm1, mm0          ; v3 v2 v1 v0 v7 v6 v5 v4
+                           punpckldq mm0, mm0     ; v7 v6 v5 v4 v7 v6 v5 v4
+                           punpckhdq mm1, mm1     ; v3 v2 v1 v0 v3 v2 v1 v0
+                           movq [edi], mm0
+                           movq [edi + 8], mm0
+                           movq [edi + 16], mm0
+                           movq [edi + 24], mm0
+                           movq [edi+32], mm1
+                           movq [edi + 40], mm1
+                           movq [edi+ 48], mm1
+                           sub esi, 8
+                           movq [edi + 56], mm1
+                           sub edi, 64
+                           sub ecx, 2
+                           jnz loop4_pass0
+                           EMMS
+                        }
+                     }
+
+                     sptr -= (width_mmx*4 - 4);            // sign fixed
+                     dp -= (width_mmx*32 - 4);            // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 4;
+                        png_memcpy(v, sptr, 4);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 4;
+                           png_memcpy(dp, v, 4);
+                        }
+                     }
+                  }
+                  else if (((pass == 2) || (pass == 3)) && width)
+                  {
+                     int width_mmx = ((width >> 1) << 1) ;
+                     width -= width_mmx;
+                     if (width_mmx)
+                     {
+                        _asm
+                        {
+                           mov esi, sptr
+                           mov edi, dp
+                           mov ecx, width_mmx
+                           sub esi, 4
+                           sub edi, 28
+loop4_pass2:
+                           movq mm0, [esi]      ; v3 v2 v1 v0 v7 v6 v5 v4
+                           movq mm1, mm0        ; v3 v2 v1 v0 v7 v6 v5 v4
+                           punpckldq mm0, mm0   ; v7 v6 v5 v4 v7 v6 v5 v4
+                           punpckhdq mm1, mm1   ; v3 v2 v1 v0 v3 v2 v1 v0
+                           movq [edi], mm0
+                           movq [edi + 8], mm0
+                           movq [edi+16], mm1
+                           movq [edi + 24], mm1
+                           sub esi, 8
+                           sub edi, 32
+                           sub ecx, 2
+                           jnz loop4_pass2
+                           EMMS
+                        }
+                     }
+
+                     sptr -= (width_mmx*4 - 4);            // sign fixed
+                     dp -= (width_mmx*16 - 4);            // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 4;
+                        png_memcpy(v, sptr, 4);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 4;
+                           png_memcpy(dp, v, 4);
+                        }
+                     }
+                  }
+                  else if (width)  // pass == 4 or 5
+                  {
+                     int width_mmx = ((width >> 1) << 1) ;
+                     width -= width_mmx;
+                     if (width_mmx)
+                     {
+                        _asm
+                        {
+                           mov esi, sptr
+                           mov edi, dp
+                           mov ecx, width_mmx
+                           sub esi, 4
+                           sub edi, 12
+loop4_pass4:
+                           movq mm0, [esi]      ; v3 v2 v1 v0 v7 v6 v5 v4
+                           movq mm1, mm0        ; v3 v2 v1 v0 v7 v6 v5 v4
+                           punpckldq mm0, mm0   ; v7 v6 v5 v4 v7 v6 v5 v4
+                           punpckhdq mm1, mm1   ; v3 v2 v1 v0 v3 v2 v1 v0
+                           movq [edi], mm0
+                           sub esi, 8
+                           movq [edi + 8], mm1
+                           sub edi, 16
+                           sub ecx, 2
+                           jnz loop4_pass4
+                           EMMS
+                        }
+                     }
+
+                     sptr -= (width_mmx*4 - 4);          // sign fixed
+                     dp -= (width_mmx*8 - 4);            // sign fixed
+                     for (i = width; i; i--)
+                     {
+                        png_byte v[8];
+                        int j;
+                        sptr -= 4;
+                        png_memcpy(v, sptr, 4);
+                        for (j = 0; j < png_pass_inc[pass]; j++)
+                        {
+                           dp -= 4;
+                           png_memcpy(dp, v, 4);
+                        }
+                     }
+                  }
+
+               } /* end of pixel_bytes == 4 */
+
+               else if (pixel_bytes == 6)
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, 6);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, 6);
+                        dp -= 6;
+                     }
+                     sptr -= 6;
+                  }
+               } /* end of pixel_bytes == 6 */
+
+               else
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, pixel_bytes);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, pixel_bytes);
+                        dp -= pixel_bytes;
+                     }
+                     sptr-= pixel_bytes;
+                  }
+               }
+            } /* end of mmx_supported */
+
+            else /* MMX not supported:  use modified C code - takes advantage
+                  * of inlining of memcpy for a constant */
+            {
+               if (pixel_bytes == 1)
+               {
+                  for (i = width; i; i--)
+                  {
+                     int j;
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                        *dp-- = *sptr;
+                     sptr--;
+                  }
+               }
+               else if (pixel_bytes == 3)
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, pixel_bytes);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, pixel_bytes);
+                        dp -= pixel_bytes;
+                     }
+                     sptr -= pixel_bytes;
+                  }
+               }
+               else if (pixel_bytes == 2)
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, pixel_bytes);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, pixel_bytes);
+                        dp -= pixel_bytes;
+                     }
+                     sptr -= pixel_bytes;
+                  }
+               }
+               else if (pixel_bytes == 4)
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, pixel_bytes);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, pixel_bytes);
+                        dp -= pixel_bytes;
+                     }
+                     sptr -= pixel_bytes;
+                  }
+               }
+               else if (pixel_bytes == 6)
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, pixel_bytes);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, pixel_bytes);
+                        dp -= pixel_bytes;
+                     }
+                     sptr -= pixel_bytes;
+                  }
+               }
+               else
+               {
+                  for (i = width; i; i--)
+                  {
+                     png_byte v[8];
+                     int j;
+                     png_memcpy(v, sptr, pixel_bytes);
+                     for (j = 0; j < png_pass_inc[pass]; j++)
+                     {
+                        png_memcpy(dp, v, pixel_bytes);
+                        dp -= pixel_bytes;
+                     }
+                     sptr -= pixel_bytes;
+                  }
+               }
+
+            } /* end of MMX not supported */
+            break;
+         }
+      } /* end switch (row_info->pixel_depth) */
+
+      row_info->width = final_width;
+
+      row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,final_width);
+   }
+
+}
+
+#endif /* PNG_READ_INTERLACING_SUPPORTED */
+
+
+// These variables are utilized in the functions below.  They are declared
+// globally here to ensure alignment on 8-byte boundaries.
+
+union uAll {
+   __int64 use;
+   double  align;
+} LBCarryMask = {0x0101010101010101},
+  HBClearMask = {0x7f7f7f7f7f7f7f7f},
+  ActiveMask, ActiveMask2, ActiveMaskEnd, ShiftBpp, ShiftRem;
+
+
+// Optimized code for PNG Average filter decoder
+void /* PRIVATE */
+png_read_filter_row_mmx_avg(png_row_infop row_info, png_bytep row
+                            , png_bytep prev_row)
+{
+   int bpp;
+   png_uint_32 FullLength;
+   png_uint_32 MMXLength;
+   //png_uint_32 len;
+   int diff;
+
+   bpp = (row_info->pixel_depth + 7) >> 3; // Get # bytes per pixel
+   FullLength  = row_info->rowbytes; // # of bytes to filter
+   _asm {
+         // Init address pointers and offset
+         mov edi, row          // edi ==> Avg(x)
+         xor ebx, ebx          // ebx ==> x
+         mov edx, edi
+         mov esi, prev_row           // esi ==> Prior(x)
+         sub edx, bpp          // edx ==> Raw(x-bpp)
+
+         xor eax, eax
+         // Compute the Raw value for the first bpp bytes
+         //    Raw(x) = Avg(x) + (Prior(x)/2)
+davgrlp:
+         mov al, [esi + ebx]   // Load al with Prior(x)
+         inc ebx
+         shr al, 1             // divide by 2
+         add al, [edi+ebx-1]   // Add Avg(x); -1 to offset inc ebx
+         cmp ebx, bpp
+         mov [edi+ebx-1], al    // Write back Raw(x);
+                            // mov does not affect flags; -1 to offset inc ebx
+         jb davgrlp
+         // get # of bytes to alignment
+         mov diff, edi         // take start of row
+         add diff, ebx         // add bpp
+         add diff, 0xf         // add 7 + 8 to incr past alignment boundary
+         and diff, 0xfffffff8  // mask to alignment boundary
+         sub diff, edi         // subtract from start ==> value ebx at alignment
+         jz davggo
+         // fix alignment
+         // Compute the Raw value for the bytes upto the alignment boundary
+         //    Raw(x) = Avg(x) + ((Raw(x-bpp) + Prior(x))/2)
+         xor ecx, ecx
+davglp1:
+         xor eax, eax
+         mov cl, [esi + ebx]        // load cl with Prior(x)
+         mov al, [edx + ebx]  // load al with Raw(x-bpp)
+         add ax, cx
+         inc ebx
+         shr ax, 1            // divide by 2
+         add al, [edi+ebx-1]  // Add Avg(x); -1 to offset inc ebx
+         cmp ebx, diff              // Check if at alignment boundary
+         mov [edi+ebx-1], al        // Write back Raw(x);
+                            // mov does not affect flags; -1 to offset inc ebx
+         jb davglp1               // Repeat until at alignment boundary
+davggo:
+         mov eax, FullLength
+         mov ecx, eax
+         sub eax, ebx          // subtract alignment fix
+         and eax, 0x00000007   // calc bytes over mult of 8
+         sub ecx, eax          // drop over bytes from original length
+         mov MMXLength, ecx
+   } // end _asm block
+   // Now do the math for the rest of the row
+   switch ( bpp )
+   {
+      case 3:
+      {
+         ActiveMask.use  = 0x0000000000ffffff;
+         ShiftBpp.use = 24;    // == 3 * 8
+         ShiftRem.use = 40;    // == 64 - 24
+         _asm {
+            // Re-init address pointers and offset
+            movq mm7, ActiveMask
+            mov ebx, diff      // ebx ==> x = offset to alignment boundary
+            movq mm5, LBCarryMask
+            mov edi, row       // edi ==> Avg(x)
+            movq mm4, HBClearMask
+            mov esi, prev_row        // esi ==> Prior(x)
+            // PRIME the pump (load the first Raw(x-bpp) data set
+            movq mm2, [edi + ebx - 8]  // Load previous aligned 8 bytes
+                               // (we correct position in loop below)
+davg3lp:
+            movq mm0, [edi + ebx]      // Load mm0 with Avg(x)
+            // Add (Prev_row/2) to Average
+            movq mm3, mm5
+            psrlq mm2, ShiftRem      // Correct position Raw(x-bpp) data
+            movq mm1, [esi + ebx]    // Load mm1 with Prior(x)
+            movq mm6, mm7
+            pand mm3, mm1      // get lsb for each prev_row byte
+            psrlq mm1, 1       // divide prev_row bytes by 2
+            pand  mm1, mm4     // clear invalid bit 7 of each byte
+            paddb mm0, mm1     // add (Prev_row/2) to Avg for each byte
+            // Add 1st active group (Raw(x-bpp)/2) to Average with LBCarry
+            movq mm1, mm3      // now use mm1 for getting LBCarrys
+            pand mm1, mm2      // get LBCarrys for each byte where both
+                               // lsb's were == 1 (Only valid for active group)
+            psrlq mm2, 1       // divide raw bytes by 2
+            pand  mm2, mm4     // clear invalid bit 7 of each byte
+            paddb mm2, mm1     // add LBCarrys to (Raw(x-bpp)/2) for each byte
+            pand mm2, mm6      // Leave only Active Group 1 bytes to add to Avg
+            paddb mm0, mm2     // add (Raw/2) + LBCarrys to Avg for each Active
+                               //  byte
+            // Add 2nd active group (Raw(x-bpp)/2) to Average with LBCarry
+            psllq mm6, ShiftBpp  // shift the mm6 mask to cover bytes 3-5
+            movq mm2, mm0        // mov updated Raws to mm2
+            psllq mm2, ShiftBpp  // shift data to position correctly
+            movq mm1, mm3        // now use mm1 for getting LBCarrys
+            pand mm1, mm2      // get LBCarrys for each byte where both
+                               // lsb's were == 1 (Only valid for active group)
+            psrlq mm2, 1       // divide raw bytes by 2
+            pand  mm2, mm4     // clear invalid bit 7 of each byte
+            paddb mm2, mm1     // add LBCarrys to (Raw(x-bpp)/2) for each byte
+            pand mm2, mm6      // Leave only Active Group 2 bytes to add to Avg
+            paddb mm0, mm2     // add (Raw/2) + LBCarrys to Avg for each Active
+                               //  byte
+
+            // Add 3rd active group (Raw(x-bpp)/2) to Average with LBCarry
+            psllq mm6, ShiftBpp  // shift the mm6 mask to cover the last two
+                                 // bytes
+            movq mm2, mm0        // mov updated Raws to mm2
+            psllq mm2, ShiftBpp  // shift data to position correctly
+                              // Data only needs to be shifted once here to
+                              // get the correct x-bpp offset.
+            movq mm1, mm3     // now use mm1 for getting LBCarrys
+            pand mm1, mm2     // get LBCarrys for each byte where both
+                              // lsb's were == 1 (Only valid for active group)
+            psrlq mm2, 1      // divide raw bytes by 2
+            pand  mm2, mm4    // clear invalid bit 7 of each byte
+            paddb mm2, mm1    // add LBCarrys to (Raw(x-bpp)/2) for each byte
+            pand mm2, mm6     // Leave only Active Group 2 bytes to add to Avg
+            add ebx, 8
+            paddb mm0, mm2    // add (Raw/2) + LBCarrys to Avg for each Active
+                              // byte
+
+            // Now ready to write back to memory
+            movq [edi + ebx - 8], mm0
+            // Move updated Raw(x) to use as Raw(x-bpp) for next loop
+            cmp ebx, MMXLength
+            movq mm2, mm0     // mov updated Raw(x) to mm2
+            jb davg3lp
+         } // end _asm block
+      }
+      break;
+
+      case 6:
+      case 4:
+      case 7:
+      case 5:
+      {
+         ActiveMask.use  = 0xffffffffffffffff;  // use shift below to clear
+                                                // appropriate inactive bytes
+         ShiftBpp.use = bpp << 3;
+         ShiftRem.use = 64 - ShiftBpp.use;
+         _asm {
+            movq mm4, HBClearMask
+            // Re-init address pointers and offset
+            mov ebx, diff       // ebx ==> x = offset to alignment boundary
+            // Load ActiveMask and clear all bytes except for 1st active group
+            movq mm7, ActiveMask
+            mov edi, row         // edi ==> Avg(x)
+            psrlq mm7, ShiftRem
+            mov esi, prev_row    // esi ==> Prior(x)
+            movq mm6, mm7
+            movq mm5, LBCarryMask
+            psllq mm6, ShiftBpp  // Create mask for 2nd active group
+            // PRIME the pump (load the first Raw(x-bpp) data set
+            movq mm2, [edi + ebx - 8]  // Load previous aligned 8 bytes
+                                 // (we correct position in loop below)
+davg4lp:
+            movq mm0, [edi + ebx]
+            psrlq mm2, ShiftRem  // shift data to position correctly
+            movq mm1, [esi + ebx]
+            // Add (Prev_row/2) to Average
+            movq mm3, mm5
+            pand mm3, mm1     // get lsb for each prev_row byte
+            psrlq mm1, 1      // divide prev_row bytes by 2
+            pand  mm1, mm4    // clear invalid bit 7 of each byte
+            paddb mm0, mm1    // add (Prev_row/2) to Avg for each byte
+            // Add 1st active group (Raw(x-bpp)/2) to Average with LBCarry
+            movq mm1, mm3     // now use mm1 for getting LBCarrys
+            pand mm1, mm2     // get LBCarrys for each byte where both
+                              // lsb's were == 1 (Only valid for active group)
+            psrlq mm2, 1      // divide raw bytes by 2
+            pand  mm2, mm4    // clear invalid bit 7 of each byte
+            paddb mm2, mm1    // add LBCarrys to (Raw(x-bpp)/2) for each byte
+            pand mm2, mm7     // Leave only Active Group 1 bytes to add to Avg
+            paddb mm0, mm2    // add (Raw/2) + LBCarrys to Avg for each Active
+                              // byte
+            // Add 2nd active group (Raw(x-bpp)/2) to Average with LBCarry
+            movq mm2, mm0     // mov updated Raws to mm2
+            psllq mm2, ShiftBpp // shift data to position correctly
+            add ebx, 8
+            movq mm1, mm3     // now use mm1 for getting LBCarrys
+            pand mm1, mm2     // get LBCarrys for each byte where both
+                              // lsb's were == 1 (Only valid for active group)
+            psrlq mm2, 1      // divide raw bytes by 2
+            pand  mm2, mm4    // clear invalid bit 7 of each byte
+            paddb mm2, mm1    // add LBCarrys to (Raw(x-bpp)/2) for each byte
+            pand mm2, mm6     // Leave only Active Group 2 bytes to add to Avg
+            paddb mm0, mm2    // add (Raw/2) + LBCarrys to Avg for each Active
+                              // byte
+            cmp ebx, MMXLength
+            // Now ready to write back to memory
+            movq [edi + ebx - 8], mm0
+            // Prep Raw(x-bpp) for next loop
+            movq mm2, mm0     // mov updated Raws to mm2
+            jb davg4lp
+         } // end _asm block
+      }
+      break;
+      case 2:
+      {
+         ActiveMask.use  = 0x000000000000ffff;
+         ShiftBpp.use = 16;   // == 2 * 8     [BUGFIX]
+         ShiftRem.use = 48;   // == 64 - 16   [BUGFIX]
+         _asm {
+            // Load ActiveMask
+            movq mm7, ActiveMask
+            // Re-init address pointers and offset
+            mov ebx, diff     // ebx ==> x = offset to alignment boundary
+            movq mm5, LBCarryMask
+            mov edi, row      // edi ==> Avg(x)
+            movq mm4, HBClearMask
+            mov esi, prev_row  // esi ==> Prior(x)
+            // PRIME the pump (load the first Raw(x-bpp) data set
+            movq mm2, [edi + ebx - 8]  // Load previous aligned 8 bytes
+                              // (we correct position in loop below)
+davg2lp:
+            movq mm0, [edi + ebx]
+            psrlq mm2, ShiftRem  // shift data to position correctly   [BUGFIX]
+            movq mm1, [esi + ebx]
+            // Add (Prev_row/2) to Average
+            movq mm3, mm5
+            pand mm3, mm1     // get lsb for each prev_row byte
+            psrlq mm1, 1      // divide prev_row bytes by 2
+            pand  mm1, mm4    // clear invalid bit 7 of each byte
+            movq mm6, mm7
+            paddb mm0, mm1    // add (Prev_row/2) to Avg for each byte
+            // Add 1st active group (Raw(x-bpp)/2) to Average with LBCarry
+            movq mm1, mm3     // now use mm1 for getting LBCarrys
+            pand mm1, mm2     // get LBCarrys for each byte where both
+                              // lsb's were == 1 (Only valid for active group)
+            psrlq mm2, 1      // divide raw bytes by 2
+            pand  mm2, mm4    // clear invalid bit 7 of each byte
+            paddb mm2, mm1    // add LBCarrys to (Raw(x-bpp)/2) for each byte
+            pand mm2, mm6     // Leave only Active Group 1 bytes to add to Avg
+            paddb mm0, mm2 // add (Raw/2) + LBCarrys to Avg for each Active byte
+            // Add 2nd active group (Raw(x-bpp)/2) to Average with LBCarry
+            psllq mm6, ShiftBpp // shift the mm6 mask to cover bytes 2 & 3
+            movq mm2, mm0       // mov updated Raws to mm2
+            psllq mm2, ShiftBpp // shift data to position correctly
+            movq mm1, mm3       // now use mm1 for getting LBCarrys
+            pand mm1, mm2       // get LBCarrys for each byte where both
+                                // lsb's were == 1 (Only valid for active group)
+            psrlq mm2, 1        // divide raw bytes by 2
+            pand  mm2, mm4      // clear invalid bit 7 of each byte
+            paddb mm2, mm1      // add LBCarrys to (Raw(x-bpp)/2) for each byte
+            pand mm2, mm6       // Leave only Active Group 2 bytes to add to Avg
+            paddb mm0, mm2 // add (Raw/2) + LBCarrys to Avg for each Active byte
+
+            // Add rdd active group (Raw(x-bpp)/2) to Average with LBCarry
+            psllq mm6, ShiftBpp // shift the mm6 mask to cover bytes 4 & 5
+            movq mm2, mm0       // mov updated Raws to mm2
+            psllq mm2, ShiftBpp // shift data to position correctly
+                                // Data only needs to be shifted once here to
+                                // get the correct x-bpp offset.
+            movq mm1, mm3       // now use mm1 for getting LBCarrys
+            pand mm1, mm2       // get LBCarrys for each byte where both
+                                // lsb's were == 1 (Only valid for active group)
+            psrlq mm2, 1        // divide raw bytes by 2
+            pand  mm2, mm4      // clear invalid bit 7 of each byte
+            paddb mm2, mm1      // add LBCarrys to (Raw(x-bpp)/2) for each byte
+            pand mm2, mm6       // Leave only Active Group 2 bytes to add to Avg
+            paddb mm0, mm2 // add (Raw/2) + LBCarrys to Avg for each Active byte
+
+            // Add 4th active group (Raw(x-bpp)/2) to Average with LBCarry
+            psllq mm6, ShiftBpp  // shift the mm6 mask to cover bytes 6 & 7
+            movq mm2, mm0        // mov updated Raws to mm2
+            psllq mm2, ShiftBpp  // shift data to position correctly
+                                 // Data only needs to be shifted once here to
+                                 // get the correct x-bpp offset.
+            add ebx, 8
+            movq mm1, mm3    // now use mm1 for getting LBCarrys
+            pand mm1, mm2    // get LBCarrys for each byte where both
+                             // lsb's were == 1 (Only valid for active group)
+            psrlq mm2, 1     // divide raw bytes by 2
+            pand  mm2, mm4   // clear invalid bit 7 of each byte
+            paddb mm2, mm1   // add LBCarrys to (Raw(x-bpp)/2) for each byte
+            pand mm2, mm6    // Leave only Active Group 2 bytes to add to Avg
+            paddb mm0, mm2 // add (Raw/2) + LBCarrys to Avg for each Active byte
+
+            cmp ebx, MMXLength
+            // Now ready to write back to memory
+            movq [edi + ebx - 8], mm0
+            // Prep Raw(x-bpp) for next loop
+            movq mm2, mm0    // mov updated Raws to mm2
+            jb davg2lp
+        } // end _asm block
+      }
+      break;
+
+      case 1:                 // bpp == 1
+      {
+         _asm {
+            // Re-init address pointers and offset
+            mov ebx, diff     // ebx ==> x = offset to alignment boundary
+            mov edi, row      // edi ==> Avg(x)
+            cmp ebx, FullLength  // Test if offset at end of array
+            jnb davg1end
+            // Do Paeth decode for remaining bytes
+            mov esi, prev_row    // esi ==> Prior(x)
+            mov edx, edi
+            xor ecx, ecx         // zero ecx before using cl & cx in loop below
+            sub edx, bpp         // edx ==> Raw(x-bpp)
+davg1lp:
+            // Raw(x) = Avg(x) + ((Raw(x-bpp) + Prior(x))/2)
+            xor eax, eax
+            mov cl, [esi + ebx]  // load cl with Prior(x)
+            mov al, [edx + ebx]  // load al with Raw(x-bpp)
+            add ax, cx
+            inc ebx
+            shr ax, 1            // divide by 2
+            add al, [edi+ebx-1]  // Add Avg(x); -1 to offset inc ebx
+            cmp ebx, FullLength  // Check if at end of array
+            mov [edi+ebx-1], al  // Write back Raw(x);
+                         // mov does not affect flags; -1 to offset inc ebx
+            jb davg1lp
+davg1end:
+         } // end _asm block
+      }
+      return;
+
+      case 8:             // bpp == 8
+      {
+         _asm {
+            // Re-init address pointers and offset
+            mov ebx, diff           // ebx ==> x = offset to alignment boundary
+            movq mm5, LBCarryMask
+            mov edi, row            // edi ==> Avg(x)
+            movq mm4, HBClearMask
+            mov esi, prev_row       // esi ==> Prior(x)
+            // PRIME the pump (load the first Raw(x-bpp) data set
+            movq mm2, [edi + ebx - 8]  // Load previous aligned 8 bytes
+                                // (NO NEED to correct position in loop below)
+davg8lp:
+            movq mm0, [edi + ebx]
+            movq mm3, mm5
+            movq mm1, [esi + ebx]
+            add ebx, 8
+            pand mm3, mm1       // get lsb for each prev_row byte
+            psrlq mm1, 1        // divide prev_row bytes by 2
+            pand mm3, mm2       // get LBCarrys for each byte where both
+                                // lsb's were == 1
+            psrlq mm2, 1        // divide raw bytes by 2
+            pand  mm1, mm4      // clear invalid bit 7 of each byte
+            paddb mm0, mm3      // add LBCarrys to Avg for each byte
+            pand  mm2, mm4      // clear invalid bit 7 of each byte
+            paddb mm0, mm1      // add (Prev_row/2) to Avg for each byte
+            paddb mm0, mm2      // add (Raw/2) to Avg for each byte
+            cmp ebx, MMXLength
+            movq [edi + ebx - 8], mm0
+            movq mm2, mm0       // reuse as Raw(x-bpp)
+            jb davg8lp
+        } // end _asm block
+      }
+      break;
+      default:                  // bpp greater than 8
+      {
+        _asm {
+            movq mm5, LBCarryMask
+            // Re-init address pointers and offset
+            mov ebx, diff       // ebx ==> x = offset to alignment boundary
+            mov edi, row        // edi ==> Avg(x)
+            movq mm4, HBClearMask
+            mov edx, edi
+            mov esi, prev_row   // esi ==> Prior(x)
+            sub edx, bpp        // edx ==> Raw(x-bpp)
+davgAlp:
+            movq mm0, [edi + ebx]
+            movq mm3, mm5
+            movq mm1, [esi + ebx]
+            pand mm3, mm1       // get lsb for each prev_row byte
+            movq mm2, [edx + ebx]
+            psrlq mm1, 1        // divide prev_row bytes by 2
+            pand mm3, mm2       // get LBCarrys for each byte where both
+                                // lsb's were == 1
+            psrlq mm2, 1        // divide raw bytes by 2
+            pand  mm1, mm4      // clear invalid bit 7 of each byte
+            paddb mm0, mm3      // add LBCarrys to Avg for each byte
+            pand  mm2, mm4      // clear invalid bit 7 of each byte
+            paddb mm0, mm1      // add (Prev_row/2) to Avg for each byte
+            add ebx, 8
+            paddb mm0, mm2      // add (Raw/2) to Avg for each byte
+            cmp ebx, MMXLength
+            movq [edi + ebx - 8], mm0
+            jb davgAlp
+        } // end _asm block
+      }
+      break;
+   }                         // end switch ( bpp )
+
+   _asm {
+         // MMX acceleration complete now do clean-up
+         // Check if any remaining bytes left to decode
+         mov ebx, MMXLength    // ebx ==> x = offset bytes remaining after MMX
+         mov edi, row          // edi ==> Avg(x)
+         cmp ebx, FullLength   // Test if offset at end of array
+         jnb davgend
+         // Do Paeth decode for remaining bytes
+         mov esi, prev_row     // esi ==> Prior(x)
+         mov edx, edi
+         xor ecx, ecx          // zero ecx before using cl & cx in loop below
+         sub edx, bpp          // edx ==> Raw(x-bpp)
+davglp2:
+         // Raw(x) = Avg(x) + ((Raw(x-bpp) + Prior(x))/2)
+         xor eax, eax
+         mov cl, [esi + ebx]   // load cl with Prior(x)
+         mov al, [edx + ebx]   // load al with Raw(x-bpp)
+         add ax, cx
+         inc ebx
+         shr ax, 1              // divide by 2
+         add al, [edi+ebx-1]    // Add Avg(x); -1 to offset inc ebx
+         cmp ebx, FullLength    // Check if at end of array
+         mov [edi+ebx-1], al    // Write back Raw(x);
+                          // mov does not affect flags; -1 to offset inc ebx
+         jb davglp2
+davgend:
+         emms             // End MMX instructions; prep for possible FP instrs.
+   } // end _asm block
+}
+
+// Optimized code for PNG Paeth filter decoder
+void /* PRIVATE */
+png_read_filter_row_mmx_paeth(png_row_infop row_info, png_bytep row,
+                              png_bytep prev_row)
+{
+   png_uint_32 FullLength;
+   png_uint_32 MMXLength;
+   //png_uint_32 len;
+   int bpp;
+   int diff;
+   //int ptemp;
+   int patemp, pbtemp, pctemp;
+
+   bpp = (row_info->pixel_depth + 7) >> 3; // Get # bytes per pixel
+   FullLength  = row_info->rowbytes; // # of bytes to filter
+   _asm
+   {
+         xor ebx, ebx        // ebx ==> x offset
+         mov edi, row
+         xor edx, edx        // edx ==> x-bpp offset
+         mov esi, prev_row
+         xor eax, eax
+
+         // Compute the Raw value for the first bpp bytes
+         // Note: the formula works out to be always
+         //   Paeth(x) = Raw(x) + Prior(x)      where x < bpp
+dpthrlp:
+         mov al, [edi + ebx]
+         add al, [esi + ebx]
+         inc ebx
+         cmp ebx, bpp
+         mov [edi + ebx - 1], al
+         jb dpthrlp
+         // get # of bytes to alignment
+         mov diff, edi         // take start of row
+         add diff, ebx         // add bpp
+         xor ecx, ecx
+         add diff, 0xf         // add 7 + 8 to incr past alignment boundary
+         and diff, 0xfffffff8  // mask to alignment boundary
+         sub diff, edi         // subtract from start ==> value ebx at alignment
+         jz dpthgo
+         // fix alignment
+dpthlp1:
+         xor eax, eax
+         // pav = p - a = (a + b - c) - a = b - c
+         mov al, [esi + ebx]   // load Prior(x) into al
+         mov cl, [esi + edx]   // load Prior(x-bpp) into cl
+         sub eax, ecx          // subtract Prior(x-bpp)
+         mov patemp, eax       // Save pav for later use
+         xor eax, eax
+         // pbv = p - b = (a + b - c) - b = a - c
+         mov al, [edi + edx]   // load Raw(x-bpp) into al
+         sub eax, ecx          // subtract Prior(x-bpp)
+         mov ecx, eax
+         // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+         add eax, patemp       // pcv = pav + pbv
+         // pc = abs(pcv)
+         test eax, 0x80000000
+         jz dpthpca
+         neg eax               // reverse sign of neg values
+dpthpca:
+         mov pctemp, eax       // save pc for later use
+         // pb = abs(pbv)
+         test ecx, 0x80000000
+         jz dpthpba
+         neg ecx               // reverse sign of neg values
+dpthpba:
+         mov pbtemp, ecx       // save pb for later use
+         // pa = abs(pav)
+         mov eax, patemp
+         test eax, 0x80000000
+         jz dpthpaa
+         neg eax               // reverse sign of neg values
+dpthpaa:
+         mov patemp, eax       // save pa for later use
+         // test if pa <= pb
+         cmp eax, ecx
+         jna dpthabb
+         // pa > pb; now test if pb <= pc
+         cmp ecx, pctemp
+         jna dpthbbc
+         // pb > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+         mov cl, [esi + edx]  // load Prior(x-bpp) into cl
+         jmp dpthpaeth
+dpthbbc:
+         // pb <= pc; Raw(x) = Paeth(x) + Prior(x)
+         mov cl, [esi + ebx]   // load Prior(x) into cl
+         jmp dpthpaeth
+dpthabb:
+         // pa <= pb; now test if pa <= pc
+         cmp eax, pctemp
+         jna dpthabc
+         // pa > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+         mov cl, [esi + edx]  // load Prior(x-bpp) into cl
+         jmp dpthpaeth
+dpthabc:
+         // pa <= pc; Raw(x) = Paeth(x) + Raw(x-bpp)
+         mov cl, [edi + edx]  // load Raw(x-bpp) into cl
+dpthpaeth:
+         inc ebx
+         inc edx
+         // Raw(x) = (Paeth(x) + Paeth_Predictor( a, b, c )) mod 256
+         add [edi + ebx - 1], cl
+         cmp ebx, diff
+         jb dpthlp1
+dpthgo:
+         mov ecx, FullLength
+         mov eax, ecx
+         sub eax, ebx          // subtract alignment fix
+         and eax, 0x00000007   // calc bytes over mult of 8
+         sub ecx, eax          // drop over bytes from original length
+         mov MMXLength, ecx
+   } // end _asm block
+   // Now do the math for the rest of the row
+   switch ( bpp )
+   {
+      case 3:
+      {
+         ActiveMask.use = 0x0000000000ffffff;
+         ActiveMaskEnd.use = 0xffff000000000000;
+         ShiftBpp.use = 24;    // == bpp(3) * 8
+         ShiftRem.use = 40;    // == 64 - 24
+         _asm
+         {
+            mov ebx, diff
+            mov edi, row
+            mov esi, prev_row
+            pxor mm0, mm0
+            // PRIME the pump (load the first Raw(x-bpp) data set
+            movq mm1, [edi+ebx-8]
+dpth3lp:
+            psrlq mm1, ShiftRem     // shift last 3 bytes to 1st 3 bytes
+            movq mm2, [esi + ebx]   // load b=Prior(x)
+            punpcklbw mm1, mm0      // Unpack High bytes of a
+            movq mm3, [esi+ebx-8]   // Prep c=Prior(x-bpp) bytes
+            punpcklbw mm2, mm0      // Unpack High bytes of b
+            psrlq mm3, ShiftRem     // shift last 3 bytes to 1st 3 bytes
+            // pav = p - a = (a + b - c) - a = b - c
+            movq mm4, mm2
+            punpcklbw mm3, mm0      // Unpack High bytes of c
+            // pbv = p - b = (a + b - c) - b = a - c
+            movq mm5, mm1
+            psubw mm4, mm3
+            pxor mm7, mm7
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            movq mm6, mm4
+            psubw mm5, mm3
+
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            pcmpgtw mm0, mm4    // Create mask pav bytes < 0
+            paddw mm6, mm5
+            pand mm0, mm4       // Only pav bytes < 0 in mm7
+            pcmpgtw mm7, mm5    // Create mask pbv bytes < 0
+            psubw mm4, mm0
+            pand mm7, mm5       // Only pbv bytes < 0 in mm0
+            psubw mm4, mm0
+            psubw mm5, mm7
+            pxor mm0, mm0
+            pcmpgtw mm0, mm6    // Create mask pcv bytes < 0
+            pand mm0, mm6       // Only pav bytes < 0 in mm7
+            psubw mm5, mm7
+            psubw mm6, mm0
+            //  test pa <= pb
+            movq mm7, mm4
+            psubw mm6, mm0
+            pcmpgtw mm7, mm5    // pa > pb?
+            movq mm0, mm7
+            // use mm7 mask to merge pa & pb
+            pand mm5, mm7
+            // use mm0 mask copy to merge a & b
+            pand mm2, mm0
+            pandn mm7, mm4
+            pandn mm0, mm1
+            paddw mm7, mm5
+            paddw mm0, mm2
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            pcmpgtw mm7, mm6       // pab > pc?
+            pxor mm1, mm1
+            pand mm3, mm7
+            pandn mm7, mm0
+            paddw mm7, mm3
+            pxor mm0, mm0
+            packuswb mm7, mm1
+            movq mm3, [esi + ebx]   // load c=Prior(x-bpp)
+            pand mm7, ActiveMask
+            movq mm2, mm3           // load b=Prior(x) step 1
+            paddb mm7, [edi + ebx]  // add Paeth predictor with Raw(x)
+            punpcklbw mm3, mm0      // Unpack High bytes of c
+            movq [edi + ebx], mm7   // write back updated value
+            movq mm1, mm7           // Now mm1 will be used as Raw(x-bpp)
+            // Now do Paeth for 2nd set of bytes (3-5)
+            psrlq mm2, ShiftBpp     // load b=Prior(x) step 2
+            punpcklbw mm1, mm0      // Unpack High bytes of a
+            pxor mm7, mm7
+            punpcklbw mm2, mm0      // Unpack High bytes of b
+            // pbv = p - b = (a + b - c) - b = a - c
+            movq mm5, mm1
+            // pav = p - a = (a + b - c) - a = b - c
+            movq mm4, mm2
+            psubw mm5, mm3
+            psubw mm4, mm3
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) =
+            //       pav + pbv = pbv + pav
+            movq mm6, mm5
+            paddw mm6, mm4
+
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            pcmpgtw mm0, mm5       // Create mask pbv bytes < 0
+            pcmpgtw mm7, mm4       // Create mask pav bytes < 0
+            pand mm0, mm5          // Only pbv bytes < 0 in mm0
+            pand mm7, mm4          // Only pav bytes < 0 in mm7
+            psubw mm5, mm0
+            psubw mm4, mm7
+            psubw mm5, mm0
+            psubw mm4, mm7
+            pxor mm0, mm0
+            pcmpgtw mm0, mm6       // Create mask pcv bytes < 0
+            pand mm0, mm6          // Only pav bytes < 0 in mm7
+            psubw mm6, mm0
+            //  test pa <= pb
+            movq mm7, mm4
+            psubw mm6, mm0
+            pcmpgtw mm7, mm5       // pa > pb?
+            movq mm0, mm7
+            // use mm7 mask to merge pa & pb
+            pand mm5, mm7
+            // use mm0 mask copy to merge a & b
+            pand mm2, mm0
+            pandn mm7, mm4
+            pandn mm0, mm1
+            paddw mm7, mm5
+            paddw mm0, mm2
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            pcmpgtw mm7, mm6       // pab > pc?
+            movq mm2, [esi + ebx]  // load b=Prior(x)
+            pand mm3, mm7
+            pandn mm7, mm0
+            pxor mm1, mm1
+            paddw mm7, mm3
+            pxor mm0, mm0
+            packuswb mm7, mm1
+            movq mm3, mm2           // load c=Prior(x-bpp) step 1
+            pand mm7, ActiveMask
+            punpckhbw mm2, mm0      // Unpack High bytes of b
+            psllq mm7, ShiftBpp     // Shift bytes to 2nd group of 3 bytes
+             // pav = p - a = (a + b - c) - a = b - c
+            movq mm4, mm2
+            paddb mm7, [edi + ebx]  // add Paeth predictor with Raw(x)
+            psllq mm3, ShiftBpp     // load c=Prior(x-bpp) step 2
+            movq [edi + ebx], mm7   // write back updated value
+            movq mm1, mm7
+            punpckhbw mm3, mm0      // Unpack High bytes of c
+            psllq mm1, ShiftBpp     // Shift bytes
+                                    // Now mm1 will be used as Raw(x-bpp)
+            // Now do Paeth for 3rd, and final, set of bytes (6-7)
+            pxor mm7, mm7
+            punpckhbw mm1, mm0      // Unpack High bytes of a
+            psubw mm4, mm3
+            // pbv = p - b = (a + b - c) - b = a - c
+            movq mm5, mm1
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            movq mm6, mm4
+            psubw mm5, mm3
+            pxor mm0, mm0
+            paddw mm6, mm5
+
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            pcmpgtw mm0, mm4    // Create mask pav bytes < 0
+            pcmpgtw mm7, mm5    // Create mask pbv bytes < 0
+            pand mm0, mm4       // Only pav bytes < 0 in mm7
+            pand mm7, mm5       // Only pbv bytes < 0 in mm0
+            psubw mm4, mm0
+            psubw mm5, mm7
+            psubw mm4, mm0
+            psubw mm5, mm7
+            pxor mm0, mm0
+            pcmpgtw mm0, mm6    // Create mask pcv bytes < 0
+            pand mm0, mm6       // Only pav bytes < 0 in mm7
+            psubw mm6, mm0
+            //  test pa <= pb
+            movq mm7, mm4
+            psubw mm6, mm0
+            pcmpgtw mm7, mm5    // pa > pb?
+            movq mm0, mm7
+            // use mm0 mask copy to merge a & b
+            pand mm2, mm0
+            // use mm7 mask to merge pa & pb
+            pand mm5, mm7
+            pandn mm0, mm1
+            pandn mm7, mm4
+            paddw mm0, mm2
+            paddw mm7, mm5
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            pcmpgtw mm7, mm6    // pab > pc?
+            pand mm3, mm7
+            pandn mm7, mm0
+            paddw mm7, mm3
+            pxor mm1, mm1
+            packuswb mm1, mm7
+            // Step ebx to next set of 8 bytes and repeat loop til done
+            add ebx, 8
+            pand mm1, ActiveMaskEnd
+            paddb mm1, [edi + ebx - 8] // add Paeth predictor with Raw(x)
+
+            cmp ebx, MMXLength
+            pxor mm0, mm0              // pxor does not affect flags
+            movq [edi + ebx - 8], mm1  // write back updated value
+                                 // mm1 will be used as Raw(x-bpp) next loop
+                           // mm3 ready to be used as Prior(x-bpp) next loop
+            jb dpth3lp
+         } // end _asm block
+      }
+      break;
+
+      case 6:
+      case 7:
+      case 5:
+      {
+         ActiveMask.use  = 0x00000000ffffffff;
+         ActiveMask2.use = 0xffffffff00000000;
+         ShiftBpp.use = bpp << 3;    // == bpp * 8
+         ShiftRem.use = 64 - ShiftBpp.use;
+         _asm
+         {
+            mov ebx, diff
+            mov edi, row
+            mov esi, prev_row
+            // PRIME the pump (load the first Raw(x-bpp) data set
+            movq mm1, [edi+ebx-8]
+            pxor mm0, mm0
+dpth6lp:
+            // Must shift to position Raw(x-bpp) data
+            psrlq mm1, ShiftRem
+            // Do first set of 4 bytes
+            movq mm3, [esi+ebx-8]      // read c=Prior(x-bpp) bytes
+            punpcklbw mm1, mm0      // Unpack Low bytes of a
+            movq mm2, [esi + ebx]   // load b=Prior(x)
+            punpcklbw mm2, mm0      // Unpack Low bytes of b
+            // Must shift to position Prior(x-bpp) data
+            psrlq mm3, ShiftRem
+            // pav = p - a = (a + b - c) - a = b - c
+            movq mm4, mm2
+            punpcklbw mm3, mm0      // Unpack Low bytes of c
+            // pbv = p - b = (a + b - c) - b = a - c
+            movq mm5, mm1
+            psubw mm4, mm3
+            pxor mm7, mm7
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            movq mm6, mm4
+            psubw mm5, mm3
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            pcmpgtw mm0, mm4    // Create mask pav bytes < 0
+            paddw mm6, mm5
+            pand mm0, mm4       // Only pav bytes < 0 in mm7
+            pcmpgtw mm7, mm5    // Create mask pbv bytes < 0
+            psubw mm4, mm0
+            pand mm7, mm5       // Only pbv bytes < 0 in mm0
+            psubw mm4, mm0
+            psubw mm5, mm7
+            pxor mm0, mm0
+            pcmpgtw mm0, mm6    // Create mask pcv bytes < 0
+            pand mm0, mm6       // Only pav bytes < 0 in mm7
+            psubw mm5, mm7
+            psubw mm6, mm0
+            //  test pa <= pb
+            movq mm7, mm4
+            psubw mm6, mm0
+            pcmpgtw mm7, mm5    // pa > pb?
+            movq mm0, mm7
+            // use mm7 mask to merge pa & pb
+            pand mm5, mm7
+            // use mm0 mask copy to merge a & b
+            pand mm2, mm0
+            pandn mm7, mm4
+            pandn mm0, mm1
+            paddw mm7, mm5
+            paddw mm0, mm2
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            pcmpgtw mm7, mm6    // pab > pc?
+            pxor mm1, mm1
+            pand mm3, mm7
+            pandn mm7, mm0
+            paddw mm7, mm3
+            pxor mm0, mm0
+            packuswb mm7, mm1
+            movq mm3, [esi + ebx - 8]  // load c=Prior(x-bpp)
+            pand mm7, ActiveMask
+            psrlq mm3, ShiftRem
+            movq mm2, [esi + ebx]      // load b=Prior(x) step 1
+            paddb mm7, [edi + ebx]     // add Paeth predictor with Raw(x)
+            movq mm6, mm2
+            movq [edi + ebx], mm7      // write back updated value
+            movq mm1, [edi+ebx-8]
+            psllq mm6, ShiftBpp
+            movq mm5, mm7
+            psrlq mm1, ShiftRem
+            por mm3, mm6
+            psllq mm5, ShiftBpp
+            punpckhbw mm3, mm0         // Unpack High bytes of c
+            por mm1, mm5
+            // Do second set of 4 bytes
+            punpckhbw mm2, mm0         // Unpack High bytes of b
+            punpckhbw mm1, mm0         // Unpack High bytes of a
+            // pav = p - a = (a + b - c) - a = b - c
+            movq mm4, mm2
+            // pbv = p - b = (a + b - c) - b = a - c
+            movq mm5, mm1
+            psubw mm4, mm3
+            pxor mm7, mm7
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            movq mm6, mm4
+            psubw mm5, mm3
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            pcmpgtw mm0, mm4       // Create mask pav bytes < 0
+            paddw mm6, mm5
+            pand mm0, mm4          // Only pav bytes < 0 in mm7
+            pcmpgtw mm7, mm5       // Create mask pbv bytes < 0
+            psubw mm4, mm0
+            pand mm7, mm5          // Only pbv bytes < 0 in mm0
+            psubw mm4, mm0
+            psubw mm5, mm7
+            pxor mm0, mm0
+            pcmpgtw mm0, mm6       // Create mask pcv bytes < 0
+            pand mm0, mm6          // Only pav bytes < 0 in mm7
+            psubw mm5, mm7
+            psubw mm6, mm0
+            //  test pa <= pb
+            movq mm7, mm4
+            psubw mm6, mm0
+            pcmpgtw mm7, mm5       // pa > pb?
+            movq mm0, mm7
+            // use mm7 mask to merge pa & pb
+            pand mm5, mm7
+            // use mm0 mask copy to merge a & b
+            pand mm2, mm0
+            pandn mm7, mm4
+            pandn mm0, mm1
+            paddw mm7, mm5
+            paddw mm0, mm2
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            pcmpgtw mm7, mm6           // pab > pc?
+            pxor mm1, mm1
+            pand mm3, mm7
+            pandn mm7, mm0
+            pxor mm1, mm1
+            paddw mm7, mm3
+            pxor mm0, mm0
+            // Step ex to next set of 8 bytes and repeat loop til done
+            add ebx, 8
+            packuswb mm1, mm7
+            paddb mm1, [edi + ebx - 8]     // add Paeth predictor with Raw(x)
+            cmp ebx, MMXLength
+            movq [edi + ebx - 8], mm1      // write back updated value
+                                // mm1 will be used as Raw(x-bpp) next loop
+            jb dpth6lp
+         } // end _asm block
+      }
+      break;
+
+      case 4:
+      {
+         ActiveMask.use  = 0x00000000ffffffff;
+         _asm {
+            mov ebx, diff
+            mov edi, row
+            mov esi, prev_row
+            pxor mm0, mm0
+            // PRIME the pump (load the first Raw(x-bpp) data set
+            movq mm1, [edi+ebx-8]    // Only time should need to read
+                                     //  a=Raw(x-bpp) bytes
+dpth4lp:
+            // Do first set of 4 bytes
+            movq mm3, [esi+ebx-8]    // read c=Prior(x-bpp) bytes
+            punpckhbw mm1, mm0       // Unpack Low bytes of a
+            movq mm2, [esi + ebx]    // load b=Prior(x)
+            punpcklbw mm2, mm0       // Unpack High bytes of b
+            // pav = p - a = (a + b - c) - a = b - c
+            movq mm4, mm2
+            punpckhbw mm3, mm0       // Unpack High bytes of c
+            // pbv = p - b = (a + b - c) - b = a - c
+            movq mm5, mm1
+            psubw mm4, mm3
+            pxor mm7, mm7
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            movq mm6, mm4
+            psubw mm5, mm3
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            pcmpgtw mm0, mm4       // Create mask pav bytes < 0
+            paddw mm6, mm5
+            pand mm0, mm4          // Only pav bytes < 0 in mm7
+            pcmpgtw mm7, mm5       // Create mask pbv bytes < 0
+            psubw mm4, mm0
+            pand mm7, mm5          // Only pbv bytes < 0 in mm0
+            psubw mm4, mm0
+            psubw mm5, mm7
+            pxor mm0, mm0
+            pcmpgtw mm0, mm6       // Create mask pcv bytes < 0
+            pand mm0, mm6          // Only pav bytes < 0 in mm7
+            psubw mm5, mm7
+            psubw mm6, mm0
+            //  test pa <= pb
+            movq mm7, mm4
+            psubw mm6, mm0
+            pcmpgtw mm7, mm5       // pa > pb?
+            movq mm0, mm7
+            // use mm7 mask to merge pa & pb
+            pand mm5, mm7
+            // use mm0 mask copy to merge a & b
+            pand mm2, mm0
+            pandn mm7, mm4
+            pandn mm0, mm1
+            paddw mm7, mm5
+            paddw mm0, mm2
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            pcmpgtw mm7, mm6       // pab > pc?
+            pxor mm1, mm1
+            pand mm3, mm7
+            pandn mm7, mm0
+            paddw mm7, mm3
+            pxor mm0, mm0
+            packuswb mm7, mm1
+            movq mm3, [esi + ebx]      // load c=Prior(x-bpp)
+            pand mm7, ActiveMask
+            movq mm2, mm3              // load b=Prior(x) step 1
+            paddb mm7, [edi + ebx]     // add Paeth predictor with Raw(x)
+            punpcklbw mm3, mm0         // Unpack High bytes of c
+            movq [edi + ebx], mm7      // write back updated value
+            movq mm1, mm7              // Now mm1 will be used as Raw(x-bpp)
+            // Do second set of 4 bytes
+            punpckhbw mm2, mm0         // Unpack Low bytes of b
+            punpcklbw mm1, mm0         // Unpack Low bytes of a
+            // pav = p - a = (a + b - c) - a = b - c
+            movq mm4, mm2
+            // pbv = p - b = (a + b - c) - b = a - c
+            movq mm5, mm1
+            psubw mm4, mm3
+            pxor mm7, mm7
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            movq mm6, mm4
+            psubw mm5, mm3
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            pcmpgtw mm0, mm4       // Create mask pav bytes < 0
+            paddw mm6, mm5
+            pand mm0, mm4          // Only pav bytes < 0 in mm7
+            pcmpgtw mm7, mm5       // Create mask pbv bytes < 0
+            psubw mm4, mm0
+            pand mm7, mm5          // Only pbv bytes < 0 in mm0
+            psubw mm4, mm0
+            psubw mm5, mm7
+            pxor mm0, mm0
+            pcmpgtw mm0, mm6       // Create mask pcv bytes < 0
+            pand mm0, mm6          // Only pav bytes < 0 in mm7
+            psubw mm5, mm7
+            psubw mm6, mm0
+            //  test pa <= pb
+            movq mm7, mm4
+            psubw mm6, mm0
+            pcmpgtw mm7, mm5       // pa > pb?
+            movq mm0, mm7
+            // use mm7 mask to merge pa & pb
+            pand mm5, mm7
+            // use mm0 mask copy to merge a & b
+            pand mm2, mm0
+            pandn mm7, mm4
+            pandn mm0, mm1
+            paddw mm7, mm5
+            paddw mm0, mm2
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            pcmpgtw mm7, mm6       // pab > pc?
+            pxor mm1, mm1
+            pand mm3, mm7
+            pandn mm7, mm0
+            pxor mm1, mm1
+            paddw mm7, mm3
+            pxor mm0, mm0
+            // Step ex to next set of 8 bytes and repeat loop til done
+            add ebx, 8
+            packuswb mm1, mm7
+            paddb mm1, [edi + ebx - 8]     // add Paeth predictor with Raw(x)
+            cmp ebx, MMXLength
+            movq [edi + ebx - 8], mm1      // write back updated value
+                                // mm1 will be used as Raw(x-bpp) next loop
+            jb dpth4lp
+         } // end _asm block
+      }
+      break;
+      case 8:                          // bpp == 8
+      {
+         ActiveMask.use  = 0x00000000ffffffff;
+         _asm {
+            mov ebx, diff
+            mov edi, row
+            mov esi, prev_row
+            pxor mm0, mm0
+            // PRIME the pump (load the first Raw(x-bpp) data set
+            movq mm1, [edi+ebx-8]      // Only time should need to read
+                                       //  a=Raw(x-bpp) bytes
+dpth8lp:
+            // Do first set of 4 bytes
+            movq mm3, [esi+ebx-8]      // read c=Prior(x-bpp) bytes
+            punpcklbw mm1, mm0         // Unpack Low bytes of a
+            movq mm2, [esi + ebx]      // load b=Prior(x)
+            punpcklbw mm2, mm0         // Unpack Low bytes of b
+            // pav = p - a = (a + b - c) - a = b - c
+            movq mm4, mm2
+            punpcklbw mm3, mm0         // Unpack Low bytes of c
+            // pbv = p - b = (a + b - c) - b = a - c
+            movq mm5, mm1
+            psubw mm4, mm3
+            pxor mm7, mm7
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            movq mm6, mm4
+            psubw mm5, mm3
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            pcmpgtw mm0, mm4       // Create mask pav bytes < 0
+            paddw mm6, mm5
+            pand mm0, mm4          // Only pav bytes < 0 in mm7
+            pcmpgtw mm7, mm5       // Create mask pbv bytes < 0
+            psubw mm4, mm0
+            pand mm7, mm5          // Only pbv bytes < 0 in mm0
+            psubw mm4, mm0
+            psubw mm5, mm7
+            pxor mm0, mm0
+            pcmpgtw mm0, mm6       // Create mask pcv bytes < 0
+            pand mm0, mm6          // Only pav bytes < 0 in mm7
+            psubw mm5, mm7
+            psubw mm6, mm0
+            //  test pa <= pb
+            movq mm7, mm4
+            psubw mm6, mm0
+            pcmpgtw mm7, mm5       // pa > pb?
+            movq mm0, mm7
+            // use mm7 mask to merge pa & pb
+            pand mm5, mm7
+            // use mm0 mask copy to merge a & b
+            pand mm2, mm0
+            pandn mm7, mm4
+            pandn mm0, mm1
+            paddw mm7, mm5
+            paddw mm0, mm2
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            pcmpgtw mm7, mm6       // pab > pc?
+            pxor mm1, mm1
+            pand mm3, mm7
+            pandn mm7, mm0
+            paddw mm7, mm3
+            pxor mm0, mm0
+            packuswb mm7, mm1
+            movq mm3, [esi+ebx-8]    // read c=Prior(x-bpp) bytes
+            pand mm7, ActiveMask
+            movq mm2, [esi + ebx]    // load b=Prior(x)
+            paddb mm7, [edi + ebx]   // add Paeth predictor with Raw(x)
+            punpckhbw mm3, mm0       // Unpack High bytes of c
+            movq [edi + ebx], mm7    // write back updated value
+            movq mm1, [edi+ebx-8]    // read a=Raw(x-bpp) bytes
+
+            // Do second set of 4 bytes
+            punpckhbw mm2, mm0       // Unpack High bytes of b
+            punpckhbw mm1, mm0       // Unpack High bytes of a
+            // pav = p - a = (a + b - c) - a = b - c
+            movq mm4, mm2
+            // pbv = p - b = (a + b - c) - b = a - c
+            movq mm5, mm1
+            psubw mm4, mm3
+            pxor mm7, mm7
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            movq mm6, mm4
+            psubw mm5, mm3
+            // pa = abs(p-a) = abs(pav)
+            // pb = abs(p-b) = abs(pbv)
+            // pc = abs(p-c) = abs(pcv)
+            pcmpgtw mm0, mm4       // Create mask pav bytes < 0
+            paddw mm6, mm5
+            pand mm0, mm4          // Only pav bytes < 0 in mm7
+            pcmpgtw mm7, mm5       // Create mask pbv bytes < 0
+            psubw mm4, mm0
+            pand mm7, mm5          // Only pbv bytes < 0 in mm0
+            psubw mm4, mm0
+            psubw mm5, mm7
+            pxor mm0, mm0
+            pcmpgtw mm0, mm6       // Create mask pcv bytes < 0
+            pand mm0, mm6          // Only pav bytes < 0 in mm7
+            psubw mm5, mm7
+            psubw mm6, mm0
+            //  test pa <= pb
+            movq mm7, mm4
+            psubw mm6, mm0
+            pcmpgtw mm7, mm5       // pa > pb?
+            movq mm0, mm7
+            // use mm7 mask to merge pa & pb
+            pand mm5, mm7
+            // use mm0 mask copy to merge a & b
+            pand mm2, mm0
+            pandn mm7, mm4
+            pandn mm0, mm1
+            paddw mm7, mm5
+            paddw mm0, mm2
+            //  test  ((pa <= pb)? pa:pb) <= pc
+            pcmpgtw mm7, mm6       // pab > pc?
+            pxor mm1, mm1
+            pand mm3, mm7
+            pandn mm7, mm0
+            pxor mm1, mm1
+            paddw mm7, mm3
+            pxor mm0, mm0
+            // Step ex to next set of 8 bytes and repeat loop til done
+            add ebx, 8
+            packuswb mm1, mm7
+            paddb mm1, [edi + ebx - 8]     // add Paeth predictor with Raw(x)
+            cmp ebx, MMXLength
+            movq [edi + ebx - 8], mm1      // write back updated value
+                            // mm1 will be used as Raw(x-bpp) next loop
+            jb dpth8lp
+         } // end _asm block
+      }
+      break;
+
+      case 1:                // bpp = 1
+      case 2:                // bpp = 2
+      default:               // bpp > 8
+      {
+         _asm {
+            mov ebx, diff
+            cmp ebx, FullLength
+            jnb dpthdend
+            mov edi, row
+            mov esi, prev_row
+            // Do Paeth decode for remaining bytes
+            mov edx, ebx
+            xor ecx, ecx        // zero ecx before using cl & cx in loop below
+            sub edx, bpp        // Set edx = ebx - bpp
+dpthdlp:
+            xor eax, eax
+            // pav = p - a = (a + b - c) - a = b - c
+            mov al, [esi + ebx]        // load Prior(x) into al
+            mov cl, [esi + edx]        // load Prior(x-bpp) into cl
+            sub eax, ecx                 // subtract Prior(x-bpp)
+            mov patemp, eax                 // Save pav for later use
+            xor eax, eax
+            // pbv = p - b = (a + b - c) - b = a - c
+            mov al, [edi + edx]        // load Raw(x-bpp) into al
+            sub eax, ecx                 // subtract Prior(x-bpp)
+            mov ecx, eax
+            // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+            add eax, patemp                 // pcv = pav + pbv
+            // pc = abs(pcv)
+            test eax, 0x80000000
+            jz dpthdpca
+            neg eax                     // reverse sign of neg values
+dpthdpca:
+            mov pctemp, eax             // save pc for later use
+            // pb = abs(pbv)
+            test ecx, 0x80000000
+            jz dpthdpba
+            neg ecx                     // reverse sign of neg values
+dpthdpba:
+            mov pbtemp, ecx             // save pb for later use
+            // pa = abs(pav)
+            mov eax, patemp
+            test eax, 0x80000000
+            jz dpthdpaa
+            neg eax                     // reverse sign of neg values
+dpthdpaa:
+            mov patemp, eax             // save pa for later use
+            // test if pa <= pb
+            cmp eax, ecx
+            jna dpthdabb
+            // pa > pb; now test if pb <= pc
+            cmp ecx, pctemp
+            jna dpthdbbc
+            // pb > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+            mov cl, [esi + edx]  // load Prior(x-bpp) into cl
+            jmp dpthdpaeth
+dpthdbbc:
+            // pb <= pc; Raw(x) = Paeth(x) + Prior(x)
+            mov cl, [esi + ebx]        // load Prior(x) into cl
+            jmp dpthdpaeth
+dpthdabb:
+            // pa <= pb; now test if pa <= pc
+            cmp eax, pctemp
+            jna dpthdabc
+            // pa > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+            mov cl, [esi + edx]  // load Prior(x-bpp) into cl
+            jmp dpthdpaeth
+dpthdabc:
+            // pa <= pc; Raw(x) = Paeth(x) + Raw(x-bpp)
+            mov cl, [edi + edx]  // load Raw(x-bpp) into cl
+dpthdpaeth:
+            inc ebx
+            inc edx
+            // Raw(x) = (Paeth(x) + Paeth_Predictor( a, b, c )) mod 256
+            add [edi + ebx - 1], cl
+            cmp ebx, FullLength
+            jb dpthdlp
+dpthdend:
+         } // end _asm block
+      }
+      return;                   // No need to go further with this one
+   }                         // end switch ( bpp )
+   _asm
+   {
+         // MMX acceleration complete now do clean-up
+         // Check if any remaining bytes left to decode
+         mov ebx, MMXLength
+         cmp ebx, FullLength
+         jnb dpthend
+         mov edi, row
+         mov esi, prev_row
+         // Do Paeth decode for remaining bytes
+         mov edx, ebx
+         xor ecx, ecx         // zero ecx before using cl & cx in loop below
+         sub edx, bpp         // Set edx = ebx - bpp
+dpthlp2:
+         xor eax, eax
+         // pav = p - a = (a + b - c) - a = b - c
+         mov al, [esi + ebx]  // load Prior(x) into al
+         mov cl, [esi + edx]  // load Prior(x-bpp) into cl
+         sub eax, ecx         // subtract Prior(x-bpp)
+         mov patemp, eax      // Save pav for later use
+         xor eax, eax
+         // pbv = p - b = (a + b - c) - b = a - c
+         mov al, [edi + edx]  // load Raw(x-bpp) into al
+         sub eax, ecx         // subtract Prior(x-bpp)
+         mov ecx, eax
+         // pcv = p - c = (a + b - c) -c = (a - c) + (b - c) = pav + pbv
+         add eax, patemp      // pcv = pav + pbv
+         // pc = abs(pcv)
+         test eax, 0x80000000
+         jz dpthpca2
+         neg eax              // reverse sign of neg values
+dpthpca2:
+         mov pctemp, eax      // save pc for later use
+         // pb = abs(pbv)
+         test ecx, 0x80000000
+         jz dpthpba2
+         neg ecx              // reverse sign of neg values
+dpthpba2:
+         mov pbtemp, ecx      // save pb for later use
+         // pa = abs(pav)
+         mov eax, patemp
+         test eax, 0x80000000
+         jz dpthpaa2
+         neg eax              // reverse sign of neg values
+dpthpaa2:
+         mov patemp, eax      // save pa for later use
+         // test if pa <= pb
+         cmp eax, ecx
+         jna dpthabb2
+         // pa > pb; now test if pb <= pc
+         cmp ecx, pctemp
+         jna dpthbbc2
+         // pb > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+         mov cl, [esi + edx]  // load Prior(x-bpp) into cl
+         jmp dpthpaeth2
+dpthbbc2:
+         // pb <= pc; Raw(x) = Paeth(x) + Prior(x)
+         mov cl, [esi + ebx]        // load Prior(x) into cl
+         jmp dpthpaeth2
+dpthabb2:
+         // pa <= pb; now test if pa <= pc
+         cmp eax, pctemp
+         jna dpthabc2
+         // pa > pc; Raw(x) = Paeth(x) + Prior(x-bpp)
+         mov cl, [esi + edx]  // load Prior(x-bpp) into cl
+         jmp dpthpaeth2
+dpthabc2:
+         // pa <= pc; Raw(x) = Paeth(x) + Raw(x-bpp)
+         mov cl, [edi + edx]  // load Raw(x-bpp) into cl
+dpthpaeth2:
+         inc ebx
+         inc edx
+         // Raw(x) = (Paeth(x) + Paeth_Predictor( a, b, c )) mod 256
+         add [edi + ebx - 1], cl
+         cmp ebx, FullLength
+         jb dpthlp2
+dpthend:
+         emms             // End MMX instructions; prep for possible FP instrs.
+   } // end _asm block
+}
+
+// Optimized code for PNG Sub filter decoder
+void /* PRIVATE */
+png_read_filter_row_mmx_sub(png_row_infop row_info, png_bytep row)
+{
+   //int test;
+   int bpp;
+   png_uint_32 FullLength;
+   png_uint_32 MMXLength;
+   int diff;
+
+   bpp = (row_info->pixel_depth + 7) >> 3; // Get # bytes per pixel
+   FullLength  = row_info->rowbytes - bpp; // # of bytes to filter
+   _asm {
+        mov edi, row
+        mov esi, edi               // lp = row
+        add edi, bpp               // rp = row + bpp
+        xor eax, eax
+        // get # of bytes to alignment
+        mov diff, edi               // take start of row
+        add diff, 0xf               // add 7 + 8 to incr past
+                                        // alignment boundary
+        xor ebx, ebx
+        and diff, 0xfffffff8        // mask to alignment boundary
+        sub diff, edi               // subtract from start ==> value
+                                        //  ebx at alignment
+        jz dsubgo
+        // fix alignment
+dsublp1:
+        mov al, [esi+ebx]
+        add [edi+ebx], al
+        inc ebx
+        cmp ebx, diff
+        jb dsublp1
+dsubgo:
+        mov ecx, FullLength
+        mov edx, ecx
+        sub edx, ebx                  // subtract alignment fix
+        and edx, 0x00000007           // calc bytes over mult of 8
+        sub ecx, edx                  // drop over bytes from length
+        mov MMXLength, ecx
+   } // end _asm block
+
+   // Now do the math for the rest of the row
+   switch ( bpp )
+   {
+        case 3:
+        {
+         ActiveMask.use  = 0x0000ffffff000000;
+         ShiftBpp.use = 24;       // == 3 * 8
+         ShiftRem.use  = 40;      // == 64 - 24
+         _asm {
+            mov edi, row
+            movq mm7, ActiveMask  // Load ActiveMask for 2nd active byte group
+            mov esi, edi              // lp = row
+            add edi, bpp          // rp = row + bpp
+            movq mm6, mm7
+            mov ebx, diff
+            psllq mm6, ShiftBpp   // Move mask in mm6 to cover 3rd active
+                                  // byte group
+            // PRIME the pump (load the first Raw(x-bpp) data set
+            movq mm1, [edi+ebx-8]
+dsub3lp:
+            psrlq mm1, ShiftRem   // Shift data for adding 1st bpp bytes
+                          // no need for mask; shift clears inactive bytes
+            // Add 1st active group
+            movq mm0, [edi+ebx]
+            paddb mm0, mm1
+            // Add 2nd active group
+            movq mm1, mm0         // mov updated Raws to mm1
+            psllq mm1, ShiftBpp   // shift data to position correctly
+            pand mm1, mm7         // mask to use only 2nd active group
+            paddb mm0, mm1
+            // Add 3rd active group
+            movq mm1, mm0         // mov updated Raws to mm1
+            psllq mm1, ShiftBpp   // shift data to position correctly
+            pand mm1, mm6         // mask to use only 3rd active group
+            add ebx, 8
+            paddb mm0, mm1
+            cmp ebx, MMXLength
+            movq [edi+ebx-8], mm0     // Write updated Raws back to array
+            // Prep for doing 1st add at top of loop
+            movq mm1, mm0
+            jb dsub3lp
+         } // end _asm block
+      }
+      break;
+
+      case 1:
+      {
+         // Placed here just in case this is a duplicate of the
+         // non-MMX code for the SUB filter in png_read_filter_row below
+         //
+         //         png_bytep rp;
+         //         png_bytep lp;
+         //         png_uint_32 i;
+         //         bpp = (row_info->pixel_depth + 7) >> 3;
+         //         for (i = (png_uint_32)bpp, rp = row + bpp, lp = row;
+         //            i < row_info->rowbytes; i++, rp++, lp++)
+         //      {
+         //            *rp = (png_byte)(((int)(*rp) + (int)(*lp)) & 0xff);
+         //      }
+         _asm {
+            mov ebx, diff
+            mov edi, row
+            cmp ebx, FullLength
+            jnb dsub1end
+            mov esi, edi          // lp = row
+            xor eax, eax
+            add edi, bpp      // rp = row + bpp
+dsub1lp:
+            mov al, [esi+ebx]
+            add [edi+ebx], al
+            inc ebx
+            cmp ebx, FullLength
+            jb dsub1lp
+dsub1end:
+         } // end _asm block
+      }
+      return;
+
+      case 6:
+      case 7:
+      case 4:
+      case 5:
+      {
+         ShiftBpp.use = bpp << 3;
+         ShiftRem.use = 64 - ShiftBpp.use;
+         _asm {
+            mov edi, row
+            mov ebx, diff
+            mov esi, edi               // lp = row
+            add edi, bpp           // rp = row + bpp
+            // PRIME the pump (load the first Raw(x-bpp) data set
+            movq mm1, [edi+ebx-8]
+dsub4lp:
+            psrlq mm1, ShiftRem // Shift data for adding 1st bpp bytes
+                          // no need for mask; shift clears inactive bytes
+            movq mm0, [edi+ebx]
+            paddb mm0, mm1
+            // Add 2nd active group
+            movq mm1, mm0          // mov updated Raws to mm1
+            psllq mm1, ShiftBpp    // shift data to position correctly
+                                   // there is no need for any mask
+                                   // since shift clears inactive bits/bytes
+            add ebx, 8
+            paddb mm0, mm1
+            cmp ebx, MMXLength
+            movq [edi+ebx-8], mm0
+            movq mm1, mm0          // Prep for doing 1st add at top of loop
+            jb dsub4lp
+         } // end _asm block
+      }
+      break;
+
+      case 2:
+      {
+         ActiveMask.use  = 0x00000000ffff0000;
+         ShiftBpp.use = 16;       // == 2 * 8
+         ShiftRem.use = 48;       // == 64 - 16
+         _asm {
+            movq mm7, ActiveMask  // Load ActiveMask for 2nd active byte group
+            mov ebx, diff
+            movq mm6, mm7
+            mov edi, row
+            psllq mm6, ShiftBpp     // Move mask in mm6 to cover 3rd active
+                                    //  byte group
+            mov esi, edi            // lp = row
+            movq mm5, mm6
+            add edi, bpp            // rp = row + bpp
+            psllq mm5, ShiftBpp     // Move mask in mm5 to cover 4th active
+                                    //  byte group
+            // PRIME the pump (load the first Raw(x-bpp) data set
+            movq mm1, [edi+ebx-8]
+dsub2lp:
+            // Add 1st active group
+            psrlq mm1, ShiftRem     // Shift data for adding 1st bpp bytes
+                                    // no need for mask; shift clears inactive
+                                    //  bytes
+            movq mm0, [edi+ebx]
+            paddb mm0, mm1
+            // Add 2nd active group
+            movq mm1, mm0           // mov updated Raws to mm1
+            psllq mm1, ShiftBpp     // shift data to position correctly
+            pand mm1, mm7           // mask to use only 2nd active group
+            paddb mm0, mm1
+            // Add 3rd active group
+            movq mm1, mm0           // mov updated Raws to mm1
+            psllq mm1, ShiftBpp     // shift data to position correctly
+            pand mm1, mm6           // mask to use only 3rd active group
+            paddb mm0, mm1
+            // Add 4th active group
+            movq mm1, mm0           // mov updated Raws to mm1
+            psllq mm1, ShiftBpp     // shift data to position correctly
+            pand mm1, mm5           // mask to use only 4th active group
+            add ebx, 8
+            paddb mm0, mm1
+            cmp ebx, MMXLength
+            movq [edi+ebx-8], mm0   // Write updated Raws back to array
+            movq mm1, mm0           // Prep for doing 1st add at top of loop
+            jb dsub2lp
+         } // end _asm block
+      }
+      break;
+      case 8:
+      {
+         _asm {
+            mov edi, row
+            mov ebx, diff
+            mov esi, edi            // lp = row
+            add edi, bpp            // rp = row + bpp
+            mov ecx, MMXLength
+            movq mm7, [edi+ebx-8]   // PRIME the pump (load the first
+                                    // Raw(x-bpp) data set
+            and ecx, 0x0000003f     // calc bytes over mult of 64
+dsub8lp:
+            movq mm0, [edi+ebx]     // Load Sub(x) for 1st 8 bytes
+            paddb mm0, mm7
+            movq mm1, [edi+ebx+8]   // Load Sub(x) for 2nd 8 bytes
+            movq [edi+ebx], mm0    // Write Raw(x) for 1st 8 bytes
+                                   // Now mm0 will be used as Raw(x-bpp) for
+                                   // the 2nd group of 8 bytes.  This will be
+                                   // repeated for each group of 8 bytes with
+                                   // the 8th group being used as the Raw(x-bpp)
+                                   // for the 1st group of the next loop.
+            paddb mm1, mm0
+            movq mm2, [edi+ebx+16]  // Load Sub(x) for 3rd 8 bytes
+            movq [edi+ebx+8], mm1   // Write Raw(x) for 2nd 8 bytes
+            paddb mm2, mm1
+            movq mm3, [edi+ebx+24]  // Load Sub(x) for 4th 8 bytes
+            movq [edi+ebx+16], mm2  // Write Raw(x) for 3rd 8 bytes
+            paddb mm3, mm2
+            movq mm4, [edi+ebx+32]  // Load Sub(x) for 5th 8 bytes
+            movq [edi+ebx+24], mm3  // Write Raw(x) for 4th 8 bytes
+            paddb mm4, mm3
+            movq mm5, [edi+ebx+40]  // Load Sub(x) for 6th 8 bytes
+            movq [edi+ebx+32], mm4  // Write Raw(x) for 5th 8 bytes
+            paddb mm5, mm4
+            movq mm6, [edi+ebx+48]  // Load Sub(x) for 7th 8 bytes
+            movq [edi+ebx+40], mm5  // Write Raw(x) for 6th 8 bytes
+            paddb mm6, mm5
+            movq mm7, [edi+ebx+56]  // Load Sub(x) for 8th 8 bytes
+            movq [edi+ebx+48], mm6  // Write Raw(x) for 7th 8 bytes
+            add ebx, 64
+            paddb mm7, mm6
+            cmp ebx, ecx
+            movq [edi+ebx-8], mm7   // Write Raw(x) for 8th 8 bytes
+            jb dsub8lp
+            cmp ebx, MMXLength
+            jnb dsub8lt8
+dsub8lpA:
+            movq mm0, [edi+ebx]
+            add ebx, 8
+            paddb mm0, mm7
+            cmp ebx, MMXLength
+            movq [edi+ebx-8], mm0   // use -8 to offset early add to ebx
+            movq mm7, mm0           // Move calculated Raw(x) data to mm1 to
+                                    // be the new Raw(x-bpp) for the next loop
+            jb dsub8lpA
+dsub8lt8:
+         } // end _asm block
+      }
+      break;
+
+      default:                // bpp greater than 8 bytes
+      {
+         _asm {
+            mov ebx, diff
+            mov edi, row
+            mov esi, edi           // lp = row
+            add edi, bpp           // rp = row + bpp
+dsubAlp:
+            movq mm0, [edi+ebx]
+            movq mm1, [esi+ebx]
+            add ebx, 8
+            paddb mm0, mm1
+            cmp ebx, MMXLength
+            movq [edi+ebx-8], mm0  // mov does not affect flags; -8 to offset
+                                   //  add ebx
+            jb dsubAlp
+         } // end _asm block
+      }
+      break;
+
+   } // end switch ( bpp )
+
+   _asm {
+        mov ebx, MMXLength
+        mov edi, row
+        cmp ebx, FullLength
+        jnb dsubend
+        mov esi, edi               // lp = row
+        xor eax, eax
+        add edi, bpp               // rp = row + bpp
+dsublp2:
+        mov al, [esi+ebx]
+        add [edi+ebx], al
+        inc ebx
+        cmp ebx, FullLength
+        jb dsublp2
+dsubend:
+        emms             // End MMX instructions; prep for possible FP instrs.
+   } // end _asm block
+}
+
+// Optimized code for PNG Up filter decoder
+void /* PRIVATE */
+png_read_filter_row_mmx_up(png_row_infop row_info, png_bytep row,
+   png_bytep prev_row)
+{
+   png_uint_32 len;
+   len  = row_info->rowbytes;       // # of bytes to filter
+   _asm {
+      mov edi, row
+      // get # of bytes to alignment
+      mov ecx, edi
+      xor ebx, ebx
+      add ecx, 0x7
+      xor eax, eax
+      and ecx, 0xfffffff8
+      mov esi, prev_row
+      sub ecx, edi
+      jz dupgo
+      // fix alignment
+duplp1:
+      mov al, [edi+ebx]
+      add al, [esi+ebx]
+      inc ebx
+      cmp ebx, ecx
+      mov [edi + ebx-1], al  // mov does not affect flags; -1 to offset inc ebx
+      jb duplp1
+dupgo:
+      mov ecx, len
+      mov edx, ecx
+      sub edx, ebx                  // subtract alignment fix
+      and edx, 0x0000003f           // calc bytes over mult of 64
+      sub ecx, edx                  // drop over bytes from length
+      // Unrolled loop - use all MMX registers and interleave to reduce
+      // number of branch instructions (loops) and reduce partial stalls
+duploop:
+      movq mm1, [esi+ebx]
+      movq mm0, [edi+ebx]
+      movq mm3, [esi+ebx+8]
+      paddb mm0, mm1
+      movq mm2, [edi+ebx+8]
+      movq [edi+ebx], mm0
+      paddb mm2, mm3
+      movq mm5, [esi+ebx+16]
+      movq [edi+ebx+8], mm2
+      movq mm4, [edi+ebx+16]
+      movq mm7, [esi+ebx+24]
+      paddb mm4, mm5
+      movq mm6, [edi+ebx+24]
+      movq [edi+ebx+16], mm4
+      paddb mm6, mm7
+      movq mm1, [esi+ebx+32]
+      movq [edi+ebx+24], mm6
+      movq mm0, [edi+ebx+32]
+      movq mm3, [esi+ebx+40]
+      paddb mm0, mm1
+      movq mm2, [edi+ebx+40]
+      movq [edi+ebx+32], mm0
+      paddb mm2, mm3
+      movq mm5, [esi+ebx+48]
+      movq [edi+ebx+40], mm2
+      movq mm4, [edi+ebx+48]
+      movq mm7, [esi+ebx+56]
+      paddb mm4, mm5
+      movq mm6, [edi+ebx+56]
+      movq [edi+ebx+48], mm4
+      add ebx, 64
+      paddb mm6, mm7
+      cmp ebx, ecx
+      movq [edi+ebx-8], mm6 // (+56)movq does not affect flags;
+                                     // -8 to offset add ebx
+      jb duploop
+
+      cmp edx, 0                     // Test for bytes over mult of 64
+      jz dupend
+
+
+      // 2 lines added by lcreeve at netins.net
+      // (mail 11 Jul 98 in png-implement list)
+      cmp edx, 8 //test for less than 8 bytes
+      jb duplt8
+
+
+      add ecx, edx
+      and edx, 0x00000007           // calc bytes over mult of 8
+      sub ecx, edx                  // drop over bytes from length
+      jz duplt8
+      // Loop using MMX registers mm0 & mm1 to update 8 bytes simultaneously
+duplpA:
+      movq mm1, [esi+ebx]
+      movq mm0, [edi+ebx]
+      add ebx, 8
+      paddb mm0, mm1
+      cmp ebx, ecx
+      movq [edi+ebx-8], mm0 // movq does not affect flags; -8 to offset add ebx
+      jb duplpA
+      cmp edx, 0            // Test for bytes over mult of 8
+      jz dupend
+duplt8:
+      xor eax, eax
+      add ecx, edx          // move over byte count into counter
+      // Loop using x86 registers to update remaining bytes
+duplp2:
+      mov al, [edi + ebx]
+      add al, [esi + ebx]
+      inc ebx
+      cmp ebx, ecx
+      mov [edi + ebx-1], al // mov does not affect flags; -1 to offset inc ebx
+      jb duplp2
+dupend:
+      // Conversion of filtered row completed
+      emms          // End MMX instructions; prep for possible FP instrs.
+   } // end _asm block
+}
+
+
+// Optimized png_read_filter_row routines
+void /* PRIVATE */
+png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep
+   row, png_bytep prev_row, int filter)
+{
+#ifdef PNG_DEBUG
+   char filnm[10];
+#endif
+
+   if (mmx_supported == 2) {
+#if !defined(PNG_1_0_X)
+       /* this should have happened in png_init_mmx_flags() already */
+       png_warning(png_ptr, "asm_flags may not have been initialized");
+#endif
+       png_mmx_support();
+   }
+
+#ifdef PNG_DEBUG
+   png_debug(1, "in png_read_filter_row\n");
+   switch (filter)
+   {
+      case 0: sprintf(filnm, "none");
+         break;
+#if !defined(PNG_1_0_X)
+      case 1: sprintf(filnm, "sub-%s",
+        (png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_SUB)? "MMX" : "x86");
+         break;
+      case 2: sprintf(filnm, "up-%s",
+        (png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_UP)? "MMX" : "x86");
+         break;
+      case 3: sprintf(filnm, "avg-%s",
+        (png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_AVG)? "MMX" : "x86");
+         break;
+      case 4: sprintf(filnm, "Paeth-%s",
+        (png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_PAETH)? "MMX":"x86");
+         break;
+#else
+      case 1: sprintf(filnm, "sub");
+         break;
+      case 2: sprintf(filnm, "up");
+         break;
+      case 3: sprintf(filnm, "avg");
+         break;
+      case 4: sprintf(filnm, "Paeth");
+         break;
+#endif
+      default: sprintf(filnm, "unknw");
+         break;
+   }
+   png_debug2(0,"row=%5d, %s, ", png_ptr->row_number, filnm);
+   png_debug2(0, "pd=%2d, b=%d, ", (int)row_info->pixel_depth,
+      (int)((row_info->pixel_depth + 7) >> 3));
+   png_debug1(0,"len=%8d, ", row_info->rowbytes);
+#endif /* PNG_DEBUG */
+
+   switch (filter)
+   {
+      case PNG_FILTER_VALUE_NONE:
+         break;
+
+      case PNG_FILTER_VALUE_SUB:
+      {
+#if !defined(PNG_1_0_X)
+         if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_SUB) &&
+             (row_info->pixel_depth >= png_ptr->mmx_bitdepth_threshold) &&
+             (row_info->rowbytes >= png_ptr->mmx_rowbytes_threshold))
+#else
+         if (mmx_supported)
+#endif
+         {
+            png_read_filter_row_mmx_sub(row_info, row);
+         }
+         else
+         {
+            png_uint_32 i;
+            png_uint_32 istop = row_info->rowbytes;
+            png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+            png_bytep rp = row + bpp;
+            png_bytep lp = row;
+
+            for (i = bpp; i < istop; i++)
+            {
+               *rp = (png_byte)(((int)(*rp) + (int)(*lp++)) & 0xff);
+               rp++;
+            }
+         }
+         break;
+      }
+
+      case PNG_FILTER_VALUE_UP:
+      {
+#if !defined(PNG_1_0_X)
+         if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_UP) &&
+             (row_info->pixel_depth >= png_ptr->mmx_bitdepth_threshold) &&
+             (row_info->rowbytes >= png_ptr->mmx_rowbytes_threshold))
+#else
+         if (mmx_supported)
+#endif
+         {
+            png_read_filter_row_mmx_up(row_info, row, prev_row);
+         }
+         else
+         {
+            png_uint_32 i;
+            png_uint_32 istop = row_info->rowbytes;
+            png_bytep rp = row;
+            png_bytep pp = prev_row;
+
+            for (i = 0; i < istop; ++i)
+            {
+               *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
+               rp++;
+            }
+         }
+         break;
+      }
+
+      case PNG_FILTER_VALUE_AVG:
+      {
+#if !defined(PNG_1_0_X)
+         if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_AVG) &&
+             (row_info->pixel_depth >= png_ptr->mmx_bitdepth_threshold) &&
+             (row_info->rowbytes >= png_ptr->mmx_rowbytes_threshold))
+#else
+         if (mmx_supported)
+#endif
+         {
+            png_read_filter_row_mmx_avg(row_info, row, prev_row);
+         }
+         else
+         {
+            png_uint_32 i;
+            png_bytep rp = row;
+            png_bytep pp = prev_row;
+            png_bytep lp = row;
+            png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+            png_uint_32 istop = row_info->rowbytes - bpp;
+
+            for (i = 0; i < bpp; i++)
+            {
+               *rp = (png_byte)(((int)(*rp) +
+                  ((int)(*pp++) >> 1)) & 0xff);
+               rp++;
+            }
+
+            for (i = 0; i < istop; i++)
+            {
+               *rp = (png_byte)(((int)(*rp) +
+                  ((int)(*pp++ + *lp++) >> 1)) & 0xff);
+               rp++;
+            }
+         }
+         break;
+      }
+
+      case PNG_FILTER_VALUE_PAETH:
+      {
+#if !defined(PNG_1_0_X)
+         if ((png_ptr->asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_PAETH) &&
+             (row_info->pixel_depth >= png_ptr->mmx_bitdepth_threshold) &&
+             (row_info->rowbytes >= png_ptr->mmx_rowbytes_threshold))
+#else
+         if (mmx_supported)
+#endif
+         {
+            png_read_filter_row_mmx_paeth(row_info, row, prev_row);
+         }
+         else
+         {
+            png_uint_32 i;
+            png_bytep rp = row;
+            png_bytep pp = prev_row;
+            png_bytep lp = row;
+            png_bytep cp = prev_row;
+            png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
+            png_uint_32 istop=row_info->rowbytes - bpp;
+
+            for (i = 0; i < bpp; i++)
+            {
+               *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
+               rp++;
+            }
+
+            for (i = 0; i < istop; i++)   // use leftover rp,pp
+            {
+               int a, b, c, pa, pb, pc, p;
+
+               a = *lp++;
+               b = *pp++;
+               c = *cp++;
+
+               p = b - c;
+               pc = a - c;
+
+#ifdef PNG_USE_ABS
+               pa = abs(p);
+               pb = abs(pc);
+               pc = abs(p + pc);
+#else
+               pa = p < 0 ? -p : p;
+               pb = pc < 0 ? -pc : pc;
+               pc = (p + pc) < 0 ? -(p + pc) : p + pc;
+#endif
+
+               /*
+                  if (pa <= pb && pa <= pc)
+                     p = a;
+                  else if (pb <= pc)
+                     p = b;
+                  else
+                     p = c;
+                */
+
+               p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
+
+               *rp = (png_byte)(((int)(*rp) + p) & 0xff);
+               rp++;
+            }
+         }
+         break;
+      }
+
+      default:
+         png_warning(png_ptr, "Ignoring bad row filter type");
+         *row=0;
+         break;
+   }
+}
+
+#endif /* PNG_ASSEMBLER_CODE_SUPPORTED && PNG_USE_PNGVCRD */
diff --git a/gs/libpng/pngwio.c b/gs/libpng/pngwio.c
new file mode 100644
index 000000000..d5d61f49e
--- /dev/null
+++ b/gs/libpng/pngwio.c
@@ -0,0 +1,228 @@
+
+/* pngwio.c - functions for data output
+ *
+ * libpng 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This file provides a location for all output.  Users who need
+ * special handling are expected to write functions that have the same
+ * arguments as these and perform similar functions, but that possibly
+ * use different output methods.  Note that you shouldn't change these
+ * functions, but rather write replacement functions and then change
+ * them at run time with png_set_write_fn(...).
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+#ifdef PNG_WRITE_SUPPORTED
+
+/* Write the data to whatever output you are using.  The default routine
+   writes to a file pointer.  Note that this routine sometimes gets called
+   with very small lengths, so you should implement some kind of simple
+   buffering if you are using unbuffered writes.  This should never be asked
+   to write more than 64K on a 16 bit machine.  */
+
+void /* PRIVATE */
+png_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   if (png_ptr->write_data_fn != NULL )
+      (*(png_ptr->write_data_fn))(png_ptr, data, length);
+   else
+      png_error(png_ptr, "Call to NULL write function");
+}
+
+#if !defined(PNG_NO_STDIO)
+/* This is the function that does the actual writing of data.  If you are
+   not writing to a standard C stream, you should create a replacement
+   write_data function and use it at run time with png_set_write_fn(), rather
+   than changing the library. */
+#ifndef USE_FAR_KEYWORD
+void PNGAPI
+png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   png_uint_32 check;
+
+#if defined(_WIN32_WCE)
+   if ( !WriteFile((HANDLE)(png_ptr->io_ptr), data, length, &check, NULL) )
+      check = 0;
+#else
+   check = fwrite(data, 1, length, (png_FILE_p)(png_ptr->io_ptr));
+#endif
+   if (check != length)
+      png_error(png_ptr, "Write Error");
+}
+#else
+/* this is the model-independent version. Since the standard I/O library
+   can't handle far buffers in the medium and small models, we have to copy
+   the data.
+*/
+
+#define NEAR_BUF_SIZE 1024
+#define MIN(a,b) (a <= b ? a : b)
+
+void PNGAPI
+png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   png_uint_32 check;
+   png_byte *near_data;  /* Needs to be "png_byte *" instead of "png_bytep" */
+   png_FILE_p io_ptr;
+
+   /* Check if data really is near. If so, use usual code. */
+   near_data = (png_byte *)CVT_PTR_NOCHECK(data);
+   io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr);
+   if ((png_bytep)near_data == data)
+   {
+#if defined(_WIN32_WCE)
+      if ( !WriteFile(io_ptr, near_data, length, &check, NULL) )
+         check = 0;
+#else
+      check = fwrite(near_data, 1, length, io_ptr);
+#endif
+   }
+   else
+   {
+      png_byte buf[NEAR_BUF_SIZE];
+      png_size_t written, remaining, err;
+      check = 0;
+      remaining = length;
+      do
+      {
+         written = MIN(NEAR_BUF_SIZE, remaining);
+         png_memcpy(buf, data, written); /* copy far buffer to near buffer */
+#if defined(_WIN32_WCE)
+         if ( !WriteFile(io_ptr, buf, written, &err, NULL) )
+            err = 0;
+#else
+         err = fwrite(buf, 1, written, io_ptr);
+#endif
+         if (err != written)
+            break;
+         else
+            check += err;
+         data += written;
+         remaining -= written;
+      }
+      while (remaining != 0);
+   }
+   if (check != length)
+      png_error(png_ptr, "Write Error");
+}
+
+#endif
+#endif
+
+/* This function is called to output any data pending writing (normally
+   to disk).  After png_flush is called, there should be no data pending
+   writing in any buffers. */
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+void /* PRIVATE */
+png_flush(png_structp png_ptr)
+{
+   if (png_ptr->output_flush_fn != NULL)
+      (*(png_ptr->output_flush_fn))(png_ptr);
+}
+
+#if !defined(PNG_NO_STDIO)
+void PNGAPI
+png_default_flush(png_structp png_ptr)
+{
+#if !defined(_WIN32_WCE)
+   png_FILE_p io_ptr;
+   io_ptr = (png_FILE_p)CVT_PTR((png_ptr->io_ptr));
+   if (io_ptr != NULL)
+      fflush(io_ptr);
+#endif
+}
+#endif
+#endif
+
+/* This function allows the application to supply new output functions for
+   libpng if standard C streams aren't being used.
+
+   This function takes as its arguments:
+   png_ptr       - pointer to a png output data structure
+   io_ptr        - pointer to user supplied structure containing info about
+                   the output functions.  May be NULL.
+   write_data_fn - pointer to a new output function that takes as its
+                   arguments a pointer to a png_struct, a pointer to
+                   data to be written, and a 32-bit unsigned int that is
+                   the number of bytes to be written.  The new write
+                   function should call png_error(png_ptr, "Error msg")
+                   to exit and output any fatal error messages.
+   flush_data_fn - pointer to a new flush function that takes as its
+                   arguments a pointer to a png_struct.  After a call to
+                   the flush function, there should be no data in any buffers
+                   or pending transmission.  If the output method doesn't do
+                   any buffering of ouput, a function prototype must still be
+                   supplied although it doesn't have to do anything.  If
+                   PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile
+                   time, output_flush_fn will be ignored, although it must be
+                   supplied for compatibility. */
+void PNGAPI
+png_set_write_fn(png_structp png_ptr, png_voidp io_ptr,
+   png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)
+{
+   png_ptr->io_ptr = io_ptr;
+
+#if !defined(PNG_NO_STDIO)
+   if (write_data_fn != NULL)
+      png_ptr->write_data_fn = write_data_fn;
+   else
+      png_ptr->write_data_fn = png_default_write_data;
+#else
+   png_ptr->write_data_fn = write_data_fn;
+#endif
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+#if !defined(PNG_NO_STDIO)
+   if (output_flush_fn != NULL)
+      png_ptr->output_flush_fn = output_flush_fn;
+   else
+      png_ptr->output_flush_fn = png_default_flush;
+#else
+   png_ptr->output_flush_fn = output_flush_fn;
+#endif
+#endif /* PNG_WRITE_FLUSH_SUPPORTED */
+
+   /* It is an error to read while writing a png file */
+   if (png_ptr->read_data_fn != NULL)
+   {
+      png_ptr->read_data_fn = NULL;
+      png_warning(png_ptr,
+         "Attempted to set both read_data_fn and write_data_fn in");
+      png_warning(png_ptr,
+         "the same structure.  Resetting read_data_fn to NULL.");
+   }
+}
+
+#if defined(USE_FAR_KEYWORD)
+#if defined(_MSC_VER)
+void *png_far_to_near(png_structp png_ptr,png_voidp ptr, int check)
+{
+   void *near_ptr;
+   void FAR *far_ptr;
+   FP_OFF(near_ptr) = FP_OFF(ptr);
+   far_ptr = (void FAR *)near_ptr;
+   if(check != 0)
+      if(FP_SEG(ptr) != FP_SEG(far_ptr))
+         png_error(png_ptr,"segment lost in conversion");
+   return(near_ptr);
+}
+#  else
+void *png_far_to_near(png_structp png_ptr,png_voidp ptr, int check)
+{
+   void *near_ptr;
+   void FAR *far_ptr;
+   near_ptr = (void FAR *)ptr;
+   far_ptr = (void FAR *)near_ptr;
+   if(check != 0)
+      if(far_ptr != ptr)
+         png_error(png_ptr,"segment lost in conversion");
+   return(near_ptr);
+}
+#   endif
+#   endif
+#endif /* PNG_WRITE_SUPPORTED */
diff --git a/gs/libpng/pngwrite.c b/gs/libpng/pngwrite.c
new file mode 100644
index 000000000..3246fdaaf
--- /dev/null
+++ b/gs/libpng/pngwrite.c
@@ -0,0 +1,1464 @@
+
+/* pngwrite.c - general routines to write a PNG file
+ *
+ * libpng 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+/* get internal access to png.h */
+#define PNG_INTERNAL
+#include "png.h"
+#ifdef PNG_WRITE_SUPPORTED
+
+/* Writes all the PNG information.  This is the suggested way to use the
+ * library.  If you have a new chunk to add, make a function to write it,
+ * and put it in the correct location here.  If you want the chunk written
+ * after the image data, put it in png_write_end().  I strongly encourage
+ * you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing
+ * the chunk, as that will keep the code from breaking if you want to just
+ * write a plain PNG file.  If you have long comments, I suggest writing
+ * them in png_write_end(), and compressing them.
+ */
+void PNGAPI
+png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr)
+{
+   png_debug(1, "in png_write_info_before_PLTE\n");
+   if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+   {
+   png_write_sig(png_ptr); /* write PNG signature */
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+   if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&(png_ptr->mng_features_permitted))
+   {
+      png_warning(png_ptr,"MNG features are not allowed in a PNG datastream\n");
+      png_ptr->mng_features_permitted=0;
+   }
+#endif
+   /* write IHDR information. */
+   png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,
+      info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,
+      info_ptr->filter_type,
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+      info_ptr->interlace_type);
+#else
+      0);
+#endif
+   /* the rest of these check to see if the valid field has the appropriate
+      flag set, and if it does, writes the chunk. */
+#if defined(PNG_WRITE_gAMA_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_gAMA)
+   {
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
+      png_write_gAMA(png_ptr, info_ptr->gamma);
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+      png_write_gAMA_fixed(png_ptr, info_ptr->int_gamma);
+#  endif
+#endif
+   }
+#endif
+#if defined(PNG_WRITE_sRGB_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_sRGB)
+      png_write_sRGB(png_ptr, (int)info_ptr->srgb_intent);
+#endif
+#if defined(PNG_WRITE_iCCP_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_iCCP)
+      png_write_iCCP(png_ptr, info_ptr->iccp_name, PNG_COMPRESSION_TYPE_BASE,
+                     info_ptr->iccp_profile, (int)info_ptr->iccp_proflen);
+#endif
+#if defined(PNG_WRITE_sBIT_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_sBIT)
+      png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);
+#endif
+#if defined(PNG_WRITE_cHRM_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_cHRM)
+   {
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+      png_write_cHRM(png_ptr,
+         info_ptr->x_white, info_ptr->y_white,
+         info_ptr->x_red, info_ptr->y_red,
+         info_ptr->x_green, info_ptr->y_green,
+         info_ptr->x_blue, info_ptr->y_blue);
+#else
+#  ifdef PNG_FIXED_POINT_SUPPORTED
+      png_write_cHRM_fixed(png_ptr,
+         info_ptr->int_x_white, info_ptr->int_y_white,
+         info_ptr->int_x_red, info_ptr->int_y_red,
+         info_ptr->int_x_green, info_ptr->int_y_green,
+         info_ptr->int_x_blue, info_ptr->int_y_blue);
+#  endif
+#endif
+   }
+#endif
+#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
+   if (info_ptr->unknown_chunks_num)
+   {
+       png_unknown_chunk *up;
+
+       png_debug(5, "writing extra chunks\n");
+
+       for (up = info_ptr->unknown_chunks;
+            up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
+            up++)
+       {
+         int keep=png_handle_as_unknown(png_ptr, up->name);
+         if (keep != PNG_HANDLE_CHUNK_NEVER &&
+            up->location && !(up->location & PNG_HAVE_PLTE) &&
+            !(up->location & PNG_HAVE_IDAT) &&
+            ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
+            (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
+         {
+            png_write_chunk(png_ptr, up->name, up->data, up->size);
+         }
+       }
+   }
+#endif
+      png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;
+   }
+}
+
+void PNGAPI
+png_write_info(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
+   int i;
+#endif
+
+   png_debug(1, "in png_write_info\n");
+
+   png_write_info_before_PLTE(png_ptr, info_ptr);
+
+   if (info_ptr->valid & PNG_INFO_PLTE)
+      png_write_PLTE(png_ptr, info_ptr->palette,
+         (png_uint_32)info_ptr->num_palette);
+   else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      png_error(png_ptr, "Valid palette required for paletted images\n");
+
+#if defined(PNG_WRITE_tRNS_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_tRNS)
+      {
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+         /* invert the alpha channel (in tRNS) */
+         if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&
+            info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+         {
+            int j;
+            for (j=0; j<(int)info_ptr->num_trans; j++)
+               info_ptr->trans[j] = (png_byte)(255 - info_ptr->trans[j]);
+         }
+#endif
+      png_write_tRNS(png_ptr, info_ptr->trans, &(info_ptr->trans_values),
+         info_ptr->num_trans, info_ptr->color_type);
+      }
+#endif
+#if defined(PNG_WRITE_bKGD_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_bKGD)
+      png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
+#endif
+#if defined(PNG_WRITE_hIST_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_hIST)
+      png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
+#endif
+#if defined(PNG_WRITE_oFFs_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_oFFs)
+      png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
+         info_ptr->offset_unit_type);
+#endif
+#if defined(PNG_WRITE_pCAL_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_pCAL)
+      png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
+         info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
+         info_ptr->pcal_units, info_ptr->pcal_params);
+#endif
+#if defined(PNG_WRITE_sCAL_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_sCAL)
+#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
+      png_write_sCAL(png_ptr, (int)info_ptr->scal_unit,
+          info_ptr->scal_pixel_width, info_ptr->scal_pixel_height);
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+      png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,
+          info_ptr->scal_s_width, info_ptr->scal_s_height);
+#else
+      png_warning(png_ptr,
+          "png_write_sCAL not supported; sCAL chunk not written.\n");
+#endif
+#endif
+#endif
+#if defined(PNG_WRITE_pHYs_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_pHYs)
+      png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
+         info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
+#endif
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_tIME)
+   {
+      png_write_tIME(png_ptr, &(info_ptr->mod_time));
+      png_ptr->mode |= PNG_WROTE_tIME;
+   }
+#endif
+#if defined(PNG_WRITE_sPLT_SUPPORTED)
+   if (info_ptr->valid & PNG_INFO_sPLT)
+     for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
+       png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
+#endif
+#if defined(PNG_WRITE_TEXT_SUPPORTED)
+   /* Check to see if we need to write text chunks */
+   for (i = 0; i < info_ptr->num_text; i++)
+   {
+      png_debug2(2, "Writing header text chunk %d, type %d\n", i,
+         info_ptr->text[i].compression);
+      /* an internationalized chunk? */
+      if (info_ptr->text[i].compression > 0)
+      {
+#if defined(PNG_WRITE_iTXt_SUPPORTED)
+          /* write international chunk */
+          png_write_iTXt(png_ptr,
+                         info_ptr->text[i].compression,
+                         info_ptr->text[i].key,
+                         info_ptr->text[i].lang,
+                         info_ptr->text[i].lang_key,
+                         info_ptr->text[i].text);
+#else
+          png_warning(png_ptr, "Unable to write international text\n");
+#endif
+          /* Mark this chunk as written */
+          info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+      }
+      /* If we want a compressed text chunk */
+      else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)
+      {
+#if defined(PNG_WRITE_zTXt_SUPPORTED)
+         /* write compressed chunk */
+         png_write_zTXt(png_ptr, info_ptr->text[i].key,
+            info_ptr->text[i].text, 0,
+            info_ptr->text[i].compression);
+#else
+         png_warning(png_ptr, "Unable to write compressed text\n");
+#endif
+         /* Mark this chunk as written */
+         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
+      }
+      else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
+      {
+#if defined(PNG_WRITE_tEXt_SUPPORTED)
+         /* write uncompressed chunk */
+         png_write_tEXt(png_ptr, info_ptr->text[i].key,
+                         info_ptr->text[i].text,
+                         0);
+#else
+         png_warning(png_ptr, "Unable to write uncompressed text\n");
+#endif
+         /* Mark this chunk as written */
+         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+      }
+   }
+#endif
+#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
+   if (info_ptr->unknown_chunks_num)
+   {
+       png_unknown_chunk *up;
+
+       png_debug(5, "writing extra chunks\n");
+
+       for (up = info_ptr->unknown_chunks;
+            up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
+            up++)
+       {
+         int keep=png_handle_as_unknown(png_ptr, up->name);
+         if (keep != PNG_HANDLE_CHUNK_NEVER &&
+            up->location && (up->location & PNG_HAVE_PLTE) &&
+            !(up->location & PNG_HAVE_IDAT) &&
+            ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
+            (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
+         {
+            png_write_chunk(png_ptr, up->name, up->data, up->size);
+         }
+       }
+   }
+#endif
+}
+
+/* Writes the end of the PNG file.  If you don't want to write comments or
+ * time information, you can pass NULL for info.  If you already wrote these
+ * in png_write_info(), do not write them again here.  If you have long
+ * comments, I suggest writing them here, and compressing them.
+ */
+void PNGAPI
+png_write_end(png_structp png_ptr, png_infop info_ptr)
+{
+   png_debug(1, "in png_write_end\n");
+   if (!(png_ptr->mode & PNG_HAVE_IDAT))
+      png_error(png_ptr, "No IDATs written into file");
+
+   /* see if user wants us to write information chunks */
+   if (info_ptr != NULL)
+   {
+#if defined(PNG_WRITE_TEXT_SUPPORTED)
+      int i; /* local index variable */
+#endif
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+      /* check to see if user has supplied a time chunk */
+      if ((info_ptr->valid & PNG_INFO_tIME) &&
+         !(png_ptr->mode & PNG_WROTE_tIME))
+         png_write_tIME(png_ptr, &(info_ptr->mod_time));
+#endif
+#if defined(PNG_WRITE_TEXT_SUPPORTED)
+      /* loop through comment chunks */
+      for (i = 0; i < info_ptr->num_text; i++)
+      {
+         png_debug2(2, "Writing trailer text chunk %d, type %d\n", i,
+            info_ptr->text[i].compression);
+         /* an internationalized chunk? */
+         if (info_ptr->text[i].compression > 0)
+         {
+#if defined(PNG_WRITE_iTXt_SUPPORTED)
+             /* write international chunk */
+             png_write_iTXt(png_ptr,
+                         info_ptr->text[i].compression,
+                         info_ptr->text[i].key,
+                         info_ptr->text[i].lang,
+                         info_ptr->text[i].lang_key,
+                         info_ptr->text[i].text);
+#else
+             png_warning(png_ptr, "Unable to write international text\n");
+#endif
+             /* Mark this chunk as written */
+             info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+         }
+         else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)
+         {
+#if defined(PNG_WRITE_zTXt_SUPPORTED)
+            /* write compressed chunk */
+            png_write_zTXt(png_ptr, info_ptr->text[i].key,
+               info_ptr->text[i].text, 0,
+               info_ptr->text[i].compression);
+#else
+            png_warning(png_ptr, "Unable to write compressed text\n");
+#endif
+            /* Mark this chunk as written */
+            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
+         }
+         else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
+         {
+#if defined(PNG_WRITE_tEXt_SUPPORTED)
+            /* write uncompressed chunk */
+            png_write_tEXt(png_ptr, info_ptr->text[i].key,
+               info_ptr->text[i].text, 0);
+#else
+            png_warning(png_ptr, "Unable to write uncompressed text\n");
+#endif
+
+            /* Mark this chunk as written */
+            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+         }
+      }
+#endif
+#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
+   if (info_ptr->unknown_chunks_num)
+   {
+       png_unknown_chunk *up;
+
+       png_debug(5, "writing extra chunks\n");
+
+       for (up = info_ptr->unknown_chunks;
+            up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
+            up++)
+       {
+         int keep=png_handle_as_unknown(png_ptr, up->name);
+         if (keep != PNG_HANDLE_CHUNK_NEVER &&
+            up->location && (up->location & PNG_AFTER_IDAT) &&
+            ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
+            (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
+         {
+            png_write_chunk(png_ptr, up->name, up->data, up->size);
+         }
+       }
+   }
+#endif
+   }
+
+   png_ptr->mode |= PNG_AFTER_IDAT;
+
+   /* write end of PNG file */
+   png_write_IEND(png_ptr);
+#if 0
+/* This flush, added in libpng-1.0.8,  causes some applications to crash
+   because they do not set png_ptr->output_flush_fn */
+   png_flush(png_ptr);
+#endif
+}
+
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+#if !defined(_WIN32_WCE)
+/* "time.h" functions are not supported on WindowsCE */
+void PNGAPI
+png_convert_from_struct_tm(png_timep ptime, struct tm FAR * ttime)
+{
+   png_debug(1, "in png_convert_from_struct_tm\n");
+   ptime->year = (png_uint_16)(1900 + ttime->tm_year);
+   ptime->month = (png_byte)(ttime->tm_mon + 1);
+   ptime->day = (png_byte)ttime->tm_mday;
+   ptime->hour = (png_byte)ttime->tm_hour;
+   ptime->minute = (png_byte)ttime->tm_min;
+   ptime->second = (png_byte)ttime->tm_sec;
+}
+
+void PNGAPI
+png_convert_from_time_t(png_timep ptime, time_t ttime)
+{
+   struct tm *tbuf;
+
+   png_debug(1, "in png_convert_from_time_t\n");
+   tbuf = gmtime(&ttime);
+   png_convert_from_struct_tm(ptime, tbuf);
+}
+#endif
+#endif
+
+/* Initialize png_ptr structure, and allocate any memory needed */
+png_structp PNGAPI
+png_create_write_struct(png_const_charp user_png_ver, png_voidp error_ptr,
+   png_error_ptr error_fn, png_error_ptr warn_fn)
+{
+#ifdef PNG_USER_MEM_SUPPORTED
+   return (png_create_write_struct_2(user_png_ver, error_ptr, error_fn,
+      warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL));
+}
+
+/* Alternate initialize png_ptr structure, and allocate any memory needed */
+png_structp PNGAPI
+png_create_write_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
+   png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
+   png_malloc_ptr malloc_fn, png_free_ptr free_fn)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+   png_structp png_ptr;
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+   jmp_buf jmpbuf;
+#endif
+#endif
+   int i;
+   png_debug(1, "in png_create_write_struct\n");
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
+      (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);
+#else
+   png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
+#endif /* PNG_USER_MEM_SUPPORTED */
+   if (png_ptr == NULL)
+      return (NULL);
+
+#if !defined(PNG_1_0_X)
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+   png_init_mmx_flags(png_ptr);   /* 1.2.0 addition */
+#endif
+#endif /* PNG_1_0_X */
+
+   /* added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+   png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
+   png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+   if (setjmp(jmpbuf))
+#else
+   if (setjmp(png_ptr->jmpbuf))
+#endif
+   {
+      png_free(png_ptr, png_ptr->zbuf);
+      png_ptr->zbuf=NULL;
+      png_destroy_struct(png_ptr);
+      return (NULL);
+   }
+#ifdef USE_FAR_KEYWORD
+   png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
+#endif
+#endif
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
+#endif /* PNG_USER_MEM_SUPPORTED */
+   png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
+
+   i=0;
+   do
+   {
+     if(user_png_ver[i] != png_libpng_ver[i])
+        png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+   } while (png_libpng_ver[i++]);
+
+   if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
+   {
+     /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
+      * we must recompile any applications that use any older library version.
+      * For versions after libpng 1.0, we will be compatible, so we need
+      * only check the first digit.
+      */
+     if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
+         (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
+         (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
+     {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+        char msg[80];
+        if (user_png_ver)
+        {
+          sprintf(msg, "Application was compiled with png.h from libpng-%.20s",
+             user_png_ver);
+          png_warning(png_ptr, msg);
+        }
+        sprintf(msg, "Application  is  running with png.c from libpng-%.20s",
+           png_libpng_ver);
+        png_warning(png_ptr, msg);
+#endif
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+        png_ptr->flags=0;
+#endif
+        png_error(png_ptr,
+           "Incompatible libpng version in application and library");
+     }
+   }
+
+   /* initialize zbuf - compression buffer */
+   png_ptr->zbuf_size = PNG_ZBUF_SIZE;
+   png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+      (png_uint_32)png_ptr->zbuf_size);
+
+   png_set_write_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL,
+      png_flush_ptr_NULL);
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+   png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
+      1, png_doublep_NULL, png_doublep_NULL);
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+/* Applications that neglect to set up their own setjmp() and then encounter
+   a png_error() will longjmp here.  Since the jmpbuf is then meaningless we
+   abort instead of returning. */
+#ifdef USE_FAR_KEYWORD
+   if (setjmp(jmpbuf))
+      PNG_ABORT();
+   png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
+#else
+   if (setjmp(png_ptr->jmpbuf))
+      PNG_ABORT();
+#endif
+#endif
+   return (png_ptr);
+}
+
+/* Initialize png_ptr structure, and allocate any memory needed */
+#undef png_write_init
+void PNGAPI
+png_write_init(png_structp png_ptr)
+{
+   /* We only come here via pre-1.0.7-compiled applications */
+   png_write_init_2(png_ptr, "1.0.6 or earlier", 0, 0);
+}
+
+void PNGAPI
+png_write_init_2(png_structp png_ptr, png_const_charp user_png_ver,
+   png_size_t png_struct_size, png_size_t png_info_size)
+{
+   /* We only come here via pre-1.0.12-compiled applications */
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+   if(png_sizeof(png_struct) > png_struct_size ||
+      png_sizeof(png_info) > png_info_size)
+   {
+      char msg[80];
+      png_ptr->warning_fn=NULL;
+      if (user_png_ver)
+      {
+        sprintf(msg, "Application was compiled with png.h from libpng-%.20s",
+           user_png_ver);
+        png_warning(png_ptr, msg);
+      }
+      sprintf(msg, "Application  is  running with png.c from libpng-%.20s",
+         png_libpng_ver);
+      png_warning(png_ptr, msg);
+   }
+#endif
+   if(png_sizeof(png_struct) > png_struct_size)
+     {
+       png_ptr->error_fn=NULL;
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+       png_ptr->flags=0;
+#endif
+       png_error(png_ptr,
+       "The png struct allocated by the application for writing is too small.");
+     }
+   if(png_sizeof(png_info) > png_info_size)
+     {
+       png_ptr->error_fn=NULL;
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+       png_ptr->flags=0;
+#endif
+       png_error(png_ptr,
+       "The info struct allocated by the application for writing is too small.");
+     }
+   png_write_init_3(&png_ptr, user_png_ver, png_struct_size);
+}
+
+
+void PNGAPI
+png_write_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
+   png_size_t png_struct_size)
+{
+   png_structp png_ptr=*ptr_ptr;
+#ifdef PNG_SETJMP_SUPPORTED
+   jmp_buf tmp_jmp; /* to save current jump buffer */
+#endif
+   int i = 0;
+   do
+   {
+     if (user_png_ver[i] != png_libpng_ver[i])
+     {
+#ifdef PNG_LEGACY_SUPPORTED
+       png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+#else
+       png_ptr->warning_fn=NULL;
+       png_warning(png_ptr,
+     "Application uses deprecated png_write_init() and should be recompiled.");
+       break;
+#endif
+     }
+   } while (png_libpng_ver[i++]);
+
+   png_debug(1, "in png_write_init_3\n");
+
+#ifdef PNG_SETJMP_SUPPORTED
+   /* save jump buffer and error functions */
+   png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
+#endif
+
+   if (png_sizeof(png_struct) > png_struct_size)
+     {
+       png_destroy_struct(png_ptr);
+       png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
+       *ptr_ptr = png_ptr;
+     }
+
+   /* reset all variables to 0 */
+   png_memset(png_ptr, 0, png_sizeof (png_struct));
+
+   /* added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+   png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
+   png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
+#endif
+
+#if !defined(PNG_1_0_X)
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+   png_init_mmx_flags(png_ptr);   /* 1.2.0 addition */
+#endif
+#endif /* PNG_1_0_X */
+
+#ifdef PNG_SETJMP_SUPPORTED
+   /* restore jump buffer */
+   png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
+#endif
+
+   png_set_write_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL,
+      png_flush_ptr_NULL);
+
+   /* initialize zbuf - compression buffer */
+   png_ptr->zbuf_size = PNG_ZBUF_SIZE;
+   png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+      (png_uint_32)png_ptr->zbuf_size);
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+   png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
+      1, png_doublep_NULL, png_doublep_NULL);
+#endif
+}
+
+/* Write a few rows of image data.  If the image is interlaced,
+ * either you will have to write the 7 sub images, or, if you
+ * have called png_set_interlace_handling(), you will have to
+ * "write" the image seven times.
+ */
+void PNGAPI
+png_write_rows(png_structp png_ptr, png_bytepp row,
+   png_uint_32 num_rows)
+{
+   png_uint_32 i; /* row counter */
+   png_bytepp rp; /* row pointer */
+
+   png_debug(1, "in png_write_rows\n");
+   /* loop through the rows */
+   for (i = 0, rp = row; i < num_rows; i++, rp++)
+   {
+      png_write_row(png_ptr, *rp);
+   }
+}
+
+/* Write the image.  You only need to call this function once, even
+ * if you are writing an interlaced image.
+ */
+void PNGAPI
+png_write_image(png_structp png_ptr, png_bytepp image)
+{
+   png_uint_32 i; /* row index */
+   int pass, num_pass; /* pass variables */
+   png_bytepp rp; /* points to current row */
+
+   png_debug(1, "in png_write_image\n");
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+   /* intialize interlace handling.  If image is not interlaced,
+      this will set pass to 1 */
+   num_pass = png_set_interlace_handling(png_ptr);
+#else
+   num_pass = 1;
+#endif
+   /* loop through passes */
+   for (pass = 0; pass < num_pass; pass++)
+   {
+      /* loop through image */
+      for (i = 0, rp = image; i < png_ptr->height; i++, rp++)
+      {
+         png_write_row(png_ptr, *rp);
+      }
+   }
+}
+
+/* called by user to write a row of image data */
+void PNGAPI
+png_write_row(png_structp png_ptr, png_bytep row)
+{
+   png_debug2(1, "in png_write_row (row %ld, pass %d)\n",
+      png_ptr->row_number, png_ptr->pass);
+   /* initialize transformations and other stuff if first time */
+   if (png_ptr->row_number == 0 && png_ptr->pass == 0)
+   {
+   /* make sure we wrote the header info */
+   if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+      png_error(png_ptr,
+         "png_write_info was never called before png_write_row.");
+
+   /* check for transforms that have been set but were defined out */
+#if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
+   if (png_ptr->transformations & PNG_INVERT_MONO)
+      png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)
+   if (png_ptr->transformations & PNG_FILLER)
+      png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && defined(PNG_READ_PACKSWAP_SUPPORTED)
+   if (png_ptr->transformations & PNG_PACKSWAP)
+      png_warning(png_ptr, "PNG_WRITE_PACKSWAP_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)
+   if (png_ptr->transformations & PNG_PACK)
+      png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)
+   if (png_ptr->transformations & PNG_SHIFT)
+      png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)
+   if (png_ptr->transformations & PNG_BGR)
+      png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined.");
+#endif
+#if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)
+   if (png_ptr->transformations & PNG_SWAP_BYTES)
+      png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined.");
+#endif
+
+      png_write_start_row(png_ptr);
+   }
+
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+   /* if interlaced and not interested in row, return */
+   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+   {
+      switch (png_ptr->pass)
+      {
+         case 0:
+            if (png_ptr->row_number & 0x07)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 1:
+            if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 2:
+            if ((png_ptr->row_number & 0x07) != 4)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 3:
+            if ((png_ptr->row_number & 0x03) || png_ptr->width < 3)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 4:
+            if ((png_ptr->row_number & 0x03) != 2)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 5:
+            if ((png_ptr->row_number & 0x01) || png_ptr->width < 2)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+         case 6:
+            if (!(png_ptr->row_number & 0x01))
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+      }
+   }
+#endif
+
+   /* set up row info for transformations */
+   png_ptr->row_info.color_type = png_ptr->color_type;
+   png_ptr->row_info.width = png_ptr->usr_width;
+   png_ptr->row_info.channels = png_ptr->usr_channels;
+   png_ptr->row_info.bit_depth = png_ptr->usr_bit_depth;
+   png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth *
+      png_ptr->row_info.channels);
+
+   png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
+      png_ptr->row_info.width);
+
+   png_debug1(3, "row_info->color_type = %d\n", png_ptr->row_info.color_type);
+   png_debug1(3, "row_info->width = %lu\n", png_ptr->row_info.width);
+   png_debug1(3, "row_info->channels = %d\n", png_ptr->row_info.channels);
+   png_debug1(3, "row_info->bit_depth = %d\n", png_ptr->row_info.bit_depth);
+   png_debug1(3, "row_info->pixel_depth = %d\n", png_ptr->row_info.pixel_depth);
+   png_debug1(3, "row_info->rowbytes = %lu\n", png_ptr->row_info.rowbytes);
+
+   /* Copy user's row into buffer, leaving room for filter byte. */
+   png_memcpy_check(png_ptr, png_ptr->row_buf + 1, row,
+      png_ptr->row_info.rowbytes);
+
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+   /* handle interlacing */
+   if (png_ptr->interlaced && png_ptr->pass < 6 &&
+      (png_ptr->transformations & PNG_INTERLACE))
+   {
+      png_do_write_interlace(&(png_ptr->row_info),
+         png_ptr->row_buf + 1, png_ptr->pass);
+      /* this should always get caught above, but still ... */
+      if (!(png_ptr->row_info.width))
+      {
+         png_write_finish_row(png_ptr);
+         return;
+      }
+   }
+#endif
+
+   /* handle other transformations */
+   if (png_ptr->transformations)
+      png_do_write_transformations(png_ptr);
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+   /* Write filter_method 64 (intrapixel differencing) only if
+    * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
+    * 2. Libpng did not write a PNG signature (this filter_method is only
+    *    used in PNG datastreams that are embedded in MNG datastreams) and
+    * 3. The application called png_permit_mng_features with a mask that
+    *    included PNG_FLAG_MNG_FILTER_64 and
+    * 4. The filter_method is 64 and
+    * 5. The color_type is RGB or RGBA
+    */
+   if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+      (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
+   {
+      /* Intrapixel differencing */
+      png_do_write_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1);
+   }
+#endif
+
+   /* Find a filter if necessary, filter the row and write it out. */
+   png_write_find_filter(png_ptr, &(png_ptr->row_info));
+
+   if (png_ptr->write_row_fn != NULL)
+      (*(png_ptr->write_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
+}
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+/* Set the automatic flush interval or 0 to turn flushing off */
+void PNGAPI
+png_set_flush(png_structp png_ptr, int nrows)
+{
+   png_debug(1, "in png_set_flush\n");
+   png_ptr->flush_dist = (nrows < 0 ? 0 : nrows);
+}
+
+/* flush the current output buffers now */
+void PNGAPI
+png_write_flush(png_structp png_ptr)
+{
+   int wrote_IDAT;
+
+   png_debug(1, "in png_write_flush\n");
+   /* We have already written out all of the data */
+   if (png_ptr->row_number >= png_ptr->num_rows)
+     return;
+
+   do
+   {
+      int ret;
+
+      /* compress the data */
+      ret = deflate(&png_ptr->zstream, Z_SYNC_FLUSH);
+      wrote_IDAT = 0;
+
+      /* check for compression errors */
+      if (ret != Z_OK)
+      {
+         if (png_ptr->zstream.msg != NULL)
+            png_error(png_ptr, png_ptr->zstream.msg);
+         else
+            png_error(png_ptr, "zlib error");
+      }
+
+      if (!(png_ptr->zstream.avail_out))
+      {
+         /* write the IDAT and reset the zlib output buffer */
+         png_write_IDAT(png_ptr, png_ptr->zbuf,
+                        png_ptr->zbuf_size);
+         png_ptr->zstream.next_out = png_ptr->zbuf;
+         png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+         wrote_IDAT = 1;
+      }
+   } while(wrote_IDAT == 1);
+
+   /* If there is any data left to be output, write it into a new IDAT */
+   if (png_ptr->zbuf_size != png_ptr->zstream.avail_out)
+   {
+      /* write the IDAT and reset the zlib output buffer */
+      png_write_IDAT(png_ptr, png_ptr->zbuf,
+                     png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+      png_ptr->zstream.next_out = png_ptr->zbuf;
+      png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+   }
+   png_ptr->flush_rows = 0;
+   png_flush(png_ptr);
+}
+#endif /* PNG_WRITE_FLUSH_SUPPORTED */
+
+/* free all memory used by the write */
+void PNGAPI
+png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)
+{
+   png_structp png_ptr = NULL;
+   png_infop info_ptr = NULL;
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_free_ptr free_fn = NULL;
+   png_voidp mem_ptr = NULL;
+#endif
+
+   png_debug(1, "in png_destroy_write_struct\n");
+   if (png_ptr_ptr != NULL)
+   {
+      png_ptr = *png_ptr_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+      free_fn = png_ptr->free_fn;
+      mem_ptr = png_ptr->mem_ptr;
+#endif
+   }
+
+   if (info_ptr_ptr != NULL)
+      info_ptr = *info_ptr_ptr;
+
+   if (info_ptr != NULL)
+   {
+      png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+      if (png_ptr->num_chunk_list)
+      {
+         png_free(png_ptr, png_ptr->chunk_list);
+         png_ptr->chunk_list=NULL;
+         png_ptr->num_chunk_list=0;
+      }
+#endif
+
+#ifdef PNG_USER_MEM_SUPPORTED
+      png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,
+         (png_voidp)mem_ptr);
+#else
+      png_destroy_struct((png_voidp)info_ptr);
+#endif
+      *info_ptr_ptr = NULL;
+   }
+
+   if (png_ptr != NULL)
+   {
+      png_write_destroy(png_ptr);
+#ifdef PNG_USER_MEM_SUPPORTED
+      png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,
+         (png_voidp)mem_ptr);
+#else
+      png_destroy_struct((png_voidp)png_ptr);
+#endif
+      *png_ptr_ptr = NULL;
+   }
+}
+
+
+/* Free any memory used in png_ptr struct (old method) */
+void /* PRIVATE */
+png_write_destroy(png_structp png_ptr)
+{
+#ifdef PNG_SETJMP_SUPPORTED
+   jmp_buf tmp_jmp; /* save jump buffer */
+#endif
+   png_error_ptr error_fn;
+   png_error_ptr warning_fn;
+   png_voidp error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_free_ptr free_fn;
+#endif
+
+   png_debug(1, "in png_write_destroy\n");
+   /* free any memory zlib uses */
+   deflateEnd(&png_ptr->zstream);
+
+   /* free our memory.  png_free checks NULL for us. */
+   png_free(png_ptr, png_ptr->zbuf);
+   png_free(png_ptr, png_ptr->row_buf);
+   png_free(png_ptr, png_ptr->prev_row);
+   png_free(png_ptr, png_ptr->sub_row);
+   png_free(png_ptr, png_ptr->up_row);
+   png_free(png_ptr, png_ptr->avg_row);
+   png_free(png_ptr, png_ptr->paeth_row);
+
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+   png_free(png_ptr, png_ptr->time_buffer);
+#endif
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+   png_free(png_ptr, png_ptr->prev_filters);
+   png_free(png_ptr, png_ptr->filter_weights);
+   png_free(png_ptr, png_ptr->inv_filter_weights);
+   png_free(png_ptr, png_ptr->filter_costs);
+   png_free(png_ptr, png_ptr->inv_filter_costs);
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+   /* reset structure */
+   png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
+#endif
+
+   error_fn = png_ptr->error_fn;
+   warning_fn = png_ptr->warning_fn;
+   error_ptr = png_ptr->error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+   free_fn = png_ptr->free_fn;
+#endif
+
+   png_memset(png_ptr, 0, png_sizeof (png_struct));
+
+   png_ptr->error_fn = error_fn;
+   png_ptr->warning_fn = warning_fn;
+   png_ptr->error_ptr = error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_ptr->free_fn = free_fn;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+   png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
+#endif
+}
+
+/* Allow the application to select one or more row filters to use. */
+void PNGAPI
+png_set_filter(png_structp png_ptr, int method, int filters)
+{
+   png_debug(1, "in png_set_filter\n");
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+   if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+      (method == PNG_INTRAPIXEL_DIFFERENCING))
+         method = PNG_FILTER_TYPE_BASE;
+#endif
+   if (method == PNG_FILTER_TYPE_BASE)
+   {
+      switch (filters & (PNG_ALL_FILTERS | 0x07))
+      {
+         case 5:
+         case 6:
+         case 7: png_warning(png_ptr, "Unknown row filter for method 0");
+         case PNG_FILTER_VALUE_NONE:  png_ptr->do_filter=PNG_FILTER_NONE; break;
+         case PNG_FILTER_VALUE_SUB:   png_ptr->do_filter=PNG_FILTER_SUB;  break;
+         case PNG_FILTER_VALUE_UP:    png_ptr->do_filter=PNG_FILTER_UP;   break;
+         case PNG_FILTER_VALUE_AVG:   png_ptr->do_filter=PNG_FILTER_AVG;  break;
+         case PNG_FILTER_VALUE_PAETH: png_ptr->do_filter=PNG_FILTER_PAETH;break;
+         default: png_ptr->do_filter = (png_byte)filters; break;
+      }
+
+      /* If we have allocated the row_buf, this means we have already started
+       * with the image and we should have allocated all of the filter buffers
+       * that have been selected.  If prev_row isn't already allocated, then
+       * it is too late to start using the filters that need it, since we
+       * will be missing the data in the previous row.  If an application
+       * wants to start and stop using particular filters during compression,
+       * it should start out with all of the filters, and then add and
+       * remove them after the start of compression.
+       */
+      if (png_ptr->row_buf != NULL)
+      {
+         if ((png_ptr->do_filter & PNG_FILTER_SUB) && png_ptr->sub_row == NULL)
+         {
+            png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
+              (png_ptr->rowbytes + 1));
+            png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
+         }
+
+         if ((png_ptr->do_filter & PNG_FILTER_UP) && png_ptr->up_row == NULL)
+         {
+            if (png_ptr->prev_row == NULL)
+            {
+               png_warning(png_ptr, "Can't add Up filter after starting");
+               png_ptr->do_filter &= ~PNG_FILTER_UP;
+            }
+            else
+            {
+               png_ptr->up_row = (png_bytep)png_malloc(png_ptr,
+                  (png_ptr->rowbytes + 1));
+               png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
+            }
+         }
+
+         if ((png_ptr->do_filter & PNG_FILTER_AVG) && png_ptr->avg_row == NULL)
+         {
+            if (png_ptr->prev_row == NULL)
+            {
+               png_warning(png_ptr, "Can't add Average filter after starting");
+               png_ptr->do_filter &= ~PNG_FILTER_AVG;
+            }
+            else
+            {
+               png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
+                  (png_ptr->rowbytes + 1));
+               png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
+            }
+         }
+
+         if ((png_ptr->do_filter & PNG_FILTER_PAETH) &&
+             png_ptr->paeth_row == NULL)
+         {
+            if (png_ptr->prev_row == NULL)
+            {
+               png_warning(png_ptr, "Can't add Paeth filter after starting");
+               png_ptr->do_filter &= (png_byte)(~PNG_FILTER_PAETH);
+            }
+            else
+            {
+               png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,
+                  (png_ptr->rowbytes + 1));
+               png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
+            }
+         }
+
+         if (png_ptr->do_filter == PNG_NO_FILTERS)
+            png_ptr->do_filter = PNG_FILTER_NONE;
+      }
+   }
+   else
+      png_error(png_ptr, "Unknown custom filter method");
+}
+
+/* This allows us to influence the way in which libpng chooses the "best"
+ * filter for the current scanline.  While the "minimum-sum-of-absolute-
+ * differences metric is relatively fast and effective, there is some
+ * question as to whether it can be improved upon by trying to keep the
+ * filtered data going to zlib more consistent, hopefully resulting in
+ * better compression.
+ */
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)      /* GRR 970116 */
+void PNGAPI
+png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,
+   int num_weights, png_doublep filter_weights,
+   png_doublep filter_costs)
+{
+   int i;
+
+   png_debug(1, "in png_set_filter_heuristics\n");
+   if (heuristic_method >= PNG_FILTER_HEURISTIC_LAST)
+   {
+      png_warning(png_ptr, "Unknown filter heuristic method");
+      return;
+   }
+
+   if (heuristic_method == PNG_FILTER_HEURISTIC_DEFAULT)
+   {
+      heuristic_method = PNG_FILTER_HEURISTIC_UNWEIGHTED;
+   }
+
+   if (num_weights < 0 || filter_weights == NULL ||
+      heuristic_method == PNG_FILTER_HEURISTIC_UNWEIGHTED)
+   {
+      num_weights = 0;
+   }
+
+   png_ptr->num_prev_filters = (png_byte)num_weights;
+   png_ptr->heuristic_method = (png_byte)heuristic_method;
+
+   if (num_weights > 0)
+   {
+      if (png_ptr->prev_filters == NULL)
+      {
+         png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr,
+            (png_uint_32)(png_sizeof(png_byte) * num_weights));
+
+         /* To make sure that the weighting starts out fairly */
+         for (i = 0; i < num_weights; i++)
+         {
+            png_ptr->prev_filters[i] = 255;
+         }
+      }
+
+      if (png_ptr->filter_weights == NULL)
+      {
+         png_ptr->filter_weights = (png_uint_16p)png_malloc(png_ptr,
+            (png_uint_32)(png_sizeof(png_uint_16) * num_weights));
+
+         png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr,
+            (png_uint_32)(png_sizeof(png_uint_16) * num_weights));
+         for (i = 0; i < num_weights; i++)
+         {
+            png_ptr->inv_filter_weights[i] =
+            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
+         }
+      }
+
+      for (i = 0; i < num_weights; i++)
+      {
+         if (filter_weights[i] < 0.0)
+         {
+            png_ptr->inv_filter_weights[i] =
+            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
+         }
+         else
+         {
+            png_ptr->inv_filter_weights[i] =
+               (png_uint_16)((double)PNG_WEIGHT_FACTOR*filter_weights[i]+0.5);
+            png_ptr->filter_weights[i] =
+               (png_uint_16)((double)PNG_WEIGHT_FACTOR/filter_weights[i]+0.5);
+         }
+      }
+   }
+
+   /* If, in the future, there are other filter methods, this would
+    * need to be based on png_ptr->filter.
+    */
+   if (png_ptr->filter_costs == NULL)
+   {
+      png_ptr->filter_costs = (png_uint_16p)png_malloc(png_ptr,
+         (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
+
+      png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr,
+         (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
+
+      for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
+      {
+         png_ptr->inv_filter_costs[i] =
+         png_ptr->filter_costs[i] = PNG_COST_FACTOR;
+      }
+   }
+
+   /* Here is where we set the relative costs of the different filters.  We
+    * should take the desired compression level into account when setting
+    * the costs, so that Paeth, for instance, has a high relative cost at low
+    * compression levels, while it has a lower relative cost at higher
+    * compression settings.  The filter types are in order of increasing
+    * relative cost, so it would be possible to do this with an algorithm.
+    */
+   for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
+   {
+      if (filter_costs == NULL || filter_costs[i] < 0.0)
+      {
+         png_ptr->inv_filter_costs[i] =
+         png_ptr->filter_costs[i] = PNG_COST_FACTOR;
+      }
+      else if (filter_costs[i] >= 1.0)
+      {
+         png_ptr->inv_filter_costs[i] =
+            (png_uint_16)((double)PNG_COST_FACTOR / filter_costs[i] + 0.5);
+         png_ptr->filter_costs[i] =
+            (png_uint_16)((double)PNG_COST_FACTOR * filter_costs[i] + 0.5);
+      }
+   }
+}
+#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
+
+void PNGAPI
+png_set_compression_level(png_structp png_ptr, int level)
+{
+   png_debug(1, "in png_set_compression_level\n");
+   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_LEVEL;
+   png_ptr->zlib_level = level;
+}
+
+void PNGAPI
+png_set_compression_mem_level(png_structp png_ptr, int mem_level)
+{
+   png_debug(1, "in png_set_compression_mem_level\n");
+   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL;
+   png_ptr->zlib_mem_level = mem_level;
+}
+
+void PNGAPI
+png_set_compression_strategy(png_structp png_ptr, int strategy)
+{
+   png_debug(1, "in png_set_compression_strategy\n");
+   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_STRATEGY;
+   png_ptr->zlib_strategy = strategy;
+}
+
+void PNGAPI
+png_set_compression_window_bits(png_structp png_ptr, int window_bits)
+{
+   if (window_bits > 15)
+      png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
+   else if (window_bits < 8)
+      png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
+#ifndef WBITS_8_OK
+   /* avoid libpng bug with 256-byte windows */
+   if (window_bits == 8)
+     {
+       png_warning(png_ptr, "Compression window is being reset to 512");
+       window_bits=9;
+     }
+#endif
+   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS;
+   png_ptr->zlib_window_bits = window_bits;
+}
+
+void PNGAPI
+png_set_compression_method(png_structp png_ptr, int method)
+{
+   png_debug(1, "in png_set_compression_method\n");
+   if (method != 8)
+      png_warning(png_ptr, "Only compression method 8 is supported by PNG");
+   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_METHOD;
+   png_ptr->zlib_method = method;
+}
+
+void PNGAPI
+png_set_write_status_fn(png_structp png_ptr, png_write_status_ptr write_row_fn)
+{
+   png_ptr->write_row_fn = write_row_fn;
+}
+
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+void PNGAPI
+png_set_write_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
+   write_user_transform_fn)
+{
+   png_debug(1, "in png_set_write_user_transform_fn\n");
+   png_ptr->transformations |= PNG_USER_TRANSFORM;
+   png_ptr->write_user_transform_fn = write_user_transform_fn;
+}
+#endif
+
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+void PNGAPI
+png_write_png(png_structp png_ptr, png_infop info_ptr,
+              int transforms, voidp params)
+{
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+   /* invert the alpha channel from opacity to transparency */
+   if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
+       png_set_invert_alpha(png_ptr);
+#endif
+
+   /* Write the file header information. */
+   png_write_info(png_ptr, info_ptr);
+
+   /* ------ these transformations don't touch the info structure ------- */
+
+#if defined(PNG_WRITE_INVERT_SUPPORTED)
+   /* invert monochrome pixels */
+   if (transforms & PNG_TRANSFORM_INVERT_MONO)
+       png_set_invert_mono(png_ptr);
+#endif
+
+#if defined(PNG_WRITE_SHIFT_SUPPORTED)
+   /* Shift the pixels up to a legal bit depth and fill in
+    * as appropriate to correctly scale the image.
+    */
+   if ((transforms & PNG_TRANSFORM_SHIFT)
+               && (info_ptr->valid & PNG_INFO_sBIT))
+       png_set_shift(png_ptr, &info_ptr->sig_bit);
+#endif
+
+#if defined(PNG_WRITE_PACK_SUPPORTED)
+   /* pack pixels into bytes */
+   if (transforms & PNG_TRANSFORM_PACKING)
+       png_set_packing(png_ptr);
+#endif
+
+#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+   /* swap location of alpha bytes from ARGB to RGBA */
+   if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
+       png_set_swap_alpha(png_ptr);
+#endif
+
+#if defined(PNG_WRITE_FILLER_SUPPORTED)
+   /* Get rid of filler (OR ALPHA) bytes, pack XRGB/RGBX/ARGB/RGBA into
+    * RGB (4 channels -> 3 channels). The second parameter is not used.
+    */
+   if (transforms & PNG_TRANSFORM_STRIP_FILLER)
+       png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
+#endif
+
+#if defined(PNG_WRITE_BGR_SUPPORTED)
+   /* flip BGR pixels to RGB */
+   if (transforms & PNG_TRANSFORM_BGR)
+       png_set_bgr(png_ptr);
+#endif
+
+#if defined(PNG_WRITE_SWAP_SUPPORTED)
+   /* swap bytes of 16-bit files to most significant byte first */
+   if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
+       png_set_swap(png_ptr);
+#endif
+
+#if defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+   /* swap bits of 1, 2, 4 bit packed pixel formats */
+   if (transforms & PNG_TRANSFORM_PACKSWAP)
+       png_set_packswap(png_ptr);
+#endif
+
+   /* ----------------------- end of transformations ------------------- */
+
+   /* write the bits */
+   if (info_ptr->valid & PNG_INFO_IDAT)
+       png_write_image(png_ptr, info_ptr->row_pointers);
+
+   /* It is REQUIRED to call this to finish writing the rest of the file */
+   png_write_end(png_ptr, info_ptr);
+
+   if(transforms == 0 || params == NULL)
+      /* quiet compiler warnings */ return;
+}
+#endif
+#endif /* PNG_WRITE_SUPPORTED */
diff --git a/gs/libpng/pngwtran.c b/gs/libpng/pngwtran.c
new file mode 100644
index 000000000..f1c8b3e62
--- /dev/null
+++ b/gs/libpng/pngwtran.c
@@ -0,0 +1,563 @@
+
+/* pngwtran.c - transforms the data in a row for PNG writers
+ *
+ * libpng version 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+#ifdef PNG_WRITE_SUPPORTED
+
+/* Transform the data according to the user's wishes.  The order of
+ * transformations is significant.
+ */
+void /* PRIVATE */
+png_do_write_transformations(png_structp png_ptr)
+{
+   png_debug(1, "in png_do_write_transformations\n");
+
+   if (png_ptr == NULL)
+      return;
+
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+   if (png_ptr->transformations & PNG_USER_TRANSFORM)
+      if(png_ptr->write_user_transform_fn != NULL)
+        (*(png_ptr->write_user_transform_fn)) /* user write transform function */
+          (png_ptr,                    /* png_ptr */
+           &(png_ptr->row_info),       /* row_info:     */
+             /*  png_uint_32 width;          width of row */
+             /*  png_uint_32 rowbytes;       number of bytes in row */
+             /*  png_byte color_type;        color type of pixels */
+             /*  png_byte bit_depth;         bit depth of samples */
+             /*  png_byte channels;          number of channels (1-4) */
+             /*  png_byte pixel_depth;       bits per pixel (depth*channels) */
+           png_ptr->row_buf + 1);      /* start of pixel data for row */
+#endif
+#if defined(PNG_WRITE_FILLER_SUPPORTED)
+   if (png_ptr->transformations & PNG_FILLER)
+      png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
+         png_ptr->flags);
+#endif
+#if defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+   if (png_ptr->transformations & PNG_PACKSWAP)
+      png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+#if defined(PNG_WRITE_PACK_SUPPORTED)
+   if (png_ptr->transformations & PNG_PACK)
+      png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1,
+         (png_uint_32)png_ptr->bit_depth);
+#endif
+#if defined(PNG_WRITE_SWAP_SUPPORTED)
+   if (png_ptr->transformations & PNG_SWAP_BYTES)
+      png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+#if defined(PNG_WRITE_SHIFT_SUPPORTED)
+   if (png_ptr->transformations & PNG_SHIFT)
+      png_do_shift(&(png_ptr->row_info), png_ptr->row_buf + 1,
+         &(png_ptr->shift));
+#endif
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+   if (png_ptr->transformations & PNG_INVERT_ALPHA)
+      png_do_write_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+   if (png_ptr->transformations & PNG_SWAP_ALPHA)
+      png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+#if defined(PNG_WRITE_BGR_SUPPORTED)
+   if (png_ptr->transformations & PNG_BGR)
+      png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+#if defined(PNG_WRITE_INVERT_SUPPORTED)
+   if (png_ptr->transformations & PNG_INVERT_MONO)
+      png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+}
+
+#if defined(PNG_WRITE_PACK_SUPPORTED)
+/* Pack pixels into bytes.  Pass the true bit depth in bit_depth.  The
+ * row_info bit depth should be 8 (one pixel per byte).  The channels
+ * should be 1 (this only happens on grayscale and paletted images).
+ */
+void /* PRIVATE */
+png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth)
+{
+   png_debug(1, "in png_do_pack\n");
+   if (row_info->bit_depth == 8 &&
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+      row_info->channels == 1)
+   {
+      switch ((int)bit_depth)
+      {
+         case 1:
+         {
+            png_bytep sp, dp;
+            int mask, v;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            sp = row;
+            dp = row;
+            mask = 0x80;
+            v = 0;
+
+            for (i = 0; i < row_width; i++)
+            {
+               if (*sp != 0)
+                  v |= mask;
+               sp++;
+               if (mask > 1)
+                  mask >>= 1;
+               else
+               {
+                  mask = 0x80;
+                  *dp = (png_byte)v;
+                  dp++;
+                  v = 0;
+               }
+            }
+            if (mask != 0x80)
+               *dp = (png_byte)v;
+            break;
+         }
+         case 2:
+         {
+            png_bytep sp, dp;
+            int shift, v;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            sp = row;
+            dp = row;
+            shift = 6;
+            v = 0;
+            for (i = 0; i < row_width; i++)
+            {
+               png_byte value;
+
+               value = (png_byte)(*sp & 0x03);
+               v |= (value << shift);
+               if (shift == 0)
+               {
+                  shift = 6;
+                  *dp = (png_byte)v;
+                  dp++;
+                  v = 0;
+               }
+               else
+                  shift -= 2;
+               sp++;
+            }
+            if (shift != 6)
+               *dp = (png_byte)v;
+            break;
+         }
+         case 4:
+         {
+            png_bytep sp, dp;
+            int shift, v;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            sp = row;
+            dp = row;
+            shift = 4;
+            v = 0;
+            for (i = 0; i < row_width; i++)
+            {
+               png_byte value;
+
+               value = (png_byte)(*sp & 0x0f);
+               v |= (value << shift);
+
+               if (shift == 0)
+               {
+                  shift = 4;
+                  *dp = (png_byte)v;
+                  dp++;
+                  v = 0;
+               }
+               else
+                  shift -= 4;
+
+               sp++;
+            }
+            if (shift != 4)
+               *dp = (png_byte)v;
+            break;
+         }
+      }
+      row_info->bit_depth = (png_byte)bit_depth;
+      row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels);
+      row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,
+         row_info->width);
+   }
+}
+#endif
+
+#if defined(PNG_WRITE_SHIFT_SUPPORTED)
+/* Shift pixel values to take advantage of whole range.  Pass the
+ * true number of bits in bit_depth.  The row should be packed
+ * according to row_info->bit_depth.  Thus, if you had a row of
+ * bit depth 4, but the pixels only had values from 0 to 7, you
+ * would pass 3 as bit_depth, and this routine would translate the
+ * data to 0 to 15.
+ */
+void /* PRIVATE */
+png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
+{
+   png_debug(1, "in png_do_shift\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL &&
+#else
+   if (
+#endif
+      row_info->color_type != PNG_COLOR_TYPE_PALETTE)
+   {
+      int shift_start[4], shift_dec[4];
+      int channels = 0;
+
+      if (row_info->color_type & PNG_COLOR_MASK_COLOR)
+      {
+         shift_start[channels] = row_info->bit_depth - bit_depth->red;
+         shift_dec[channels] = bit_depth->red;
+         channels++;
+         shift_start[channels] = row_info->bit_depth - bit_depth->green;
+         shift_dec[channels] = bit_depth->green;
+         channels++;
+         shift_start[channels] = row_info->bit_depth - bit_depth->blue;
+         shift_dec[channels] = bit_depth->blue;
+         channels++;
+      }
+      else
+      {
+         shift_start[channels] = row_info->bit_depth - bit_depth->gray;
+         shift_dec[channels] = bit_depth->gray;
+         channels++;
+      }
+      if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
+      {
+         shift_start[channels] = row_info->bit_depth - bit_depth->alpha;
+         shift_dec[channels] = bit_depth->alpha;
+         channels++;
+      }
+
+      /* with low row depths, could only be grayscale, so one channel */
+      if (row_info->bit_depth < 8)
+      {
+         png_bytep bp = row;
+         png_uint_32 i;
+         png_byte mask;
+         png_uint_32 row_bytes = row_info->rowbytes;
+
+         if (bit_depth->gray == 1 && row_info->bit_depth == 2)
+            mask = 0x55;
+         else if (row_info->bit_depth == 4 && bit_depth->gray == 3)
+            mask = 0x11;
+         else
+            mask = 0xff;
+
+         for (i = 0; i < row_bytes; i++, bp++)
+         {
+            png_uint_16 v;
+            int j;
+
+            v = *bp;
+            *bp = 0;
+            for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0])
+            {
+               if (j > 0)
+                  *bp |= (png_byte)((v << j) & 0xff);
+               else
+                  *bp |= (png_byte)((v >> (-j)) & mask);
+            }
+         }
+      }
+      else if (row_info->bit_depth == 8)
+      {
+         png_bytep bp = row;
+         png_uint_32 i;
+         png_uint_32 istop = channels * row_info->width;
+
+         for (i = 0; i < istop; i++, bp++)
+         {
+
+            png_uint_16 v;
+            int j;
+            int c = (int)(i%channels);
+
+            v = *bp;
+            *bp = 0;
+            for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
+            {
+               if (j > 0)
+                  *bp |= (png_byte)((v << j) & 0xff);
+               else
+                  *bp |= (png_byte)((v >> (-j)) & 0xff);
+            }
+         }
+      }
+      else
+      {
+         png_bytep bp;
+         png_uint_32 i;
+         png_uint_32 istop = channels * row_info->width;
+
+         for (bp = row, i = 0; i < istop; i++)
+         {
+            int c = (int)(i%channels);
+            png_uint_16 value, v;
+            int j;
+
+            v = (png_uint_16)(((png_uint_16)(*bp) << 8) + *(bp + 1));
+            value = 0;
+            for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
+            {
+               if (j > 0)
+                  value |= (png_uint_16)((v << j) & (png_uint_16)0xffff);
+               else
+                  value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff);
+            }
+            *bp++ = (png_byte)(value >> 8);
+            *bp++ = (png_byte)(value & 0xff);
+         }
+      }
+   }
+}
+#endif
+
+#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+void /* PRIVATE */
+png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_write_swap_alpha\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL)
+#endif
+   {
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+      {
+         /* This converts from ARGB to RGBA */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               png_byte save = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = save;
+            }
+         }
+         /* This converts from AARRGGBB to RRGGBBAA */
+         else
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               png_byte save[2];
+               save[0] = *(sp++);
+               save[1] = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = save[0];
+               *(dp++) = save[1];
+            }
+         }
+      }
+      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      {
+         /* This converts from AG to GA */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               png_byte save = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = save;
+            }
+         }
+         /* This converts from AAGG to GGAA */
+         else
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               png_byte save[2];
+               save[0] = *(sp++);
+               save[1] = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = save[0];
+               *(dp++) = save[1];
+            }
+         }
+      }
+   }
+}
+#endif
+
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+void /* PRIVATE */
+png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_write_invert_alpha\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL)
+#endif
+   {
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+      {
+         /* This inverts the alpha channel in RGBA */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = (png_byte)(255 - *(sp++));
+            }
+         }
+         /* This inverts the alpha channel in RRGGBBAA */
+         else
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = (png_byte)(255 - *(sp++));
+               *(dp++) = (png_byte)(255 - *(sp++));
+            }
+         }
+      }
+      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      {
+         /* This inverts the alpha channel in GA */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               *(dp++) = *(sp++);
+               *(dp++) = (png_byte)(255 - *(sp++));
+            }
+         }
+         /* This inverts the alpha channel in GGAA */
+         else
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = (png_byte)(255 - *(sp++));
+               *(dp++) = (png_byte)(255 - *(sp++));
+            }
+         }
+      }
+   }
+}
+#endif
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+/* undoes intrapixel differencing  */
+void /* PRIVATE */
+png_do_write_intrapixel(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_write_intrapixel\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+       (row_info->color_type & PNG_COLOR_MASK_COLOR))
+   {
+      int bytes_per_pixel;
+      png_uint_32 row_width = row_info->width;
+      if (row_info->bit_depth == 8)
+      {
+         png_bytep rp;
+         png_uint_32 i;
+
+         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+            bytes_per_pixel = 3;
+         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+            bytes_per_pixel = 4;
+         else
+            return;
+
+         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+         {
+            *(rp)   = (png_byte)((*rp     - *(rp+1))&0xff);
+            *(rp+2) = (png_byte)((*(rp+2) - *(rp+1))&0xff);
+         }
+      }
+      else if (row_info->bit_depth == 16)
+      {
+         png_bytep rp;
+         png_uint_32 i;
+
+         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+            bytes_per_pixel = 6;
+         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+            bytes_per_pixel = 8;
+         else
+            return;
+
+         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+         {
+            png_uint_32 s0   = (*(rp  ) << 8) | *(rp+1);
+            png_uint_32 s1   = (*(rp+2) << 8) | *(rp+3);
+            png_uint_32 s2   = (*(rp+4) << 8) | *(rp+5);
+            png_uint_32 red  = (png_uint_32)((s0-s1) & 0xffffL);
+            png_uint_32 blue = (png_uint_32)((s2-s1) & 0xffffL);
+            *(rp  ) = (png_byte)((red >> 8) & 0xff);
+            *(rp+1) = (png_byte)(red & 0xff);
+            *(rp+4) = (png_byte)((blue >> 8) & 0xff);
+            *(rp+5) = (png_byte)(blue & 0xff);
+         }
+      }
+   }
+}
+#endif /* PNG_MNG_FEATURES_SUPPORTED */
+#endif /* PNG_WRITE_SUPPORTED */
diff --git a/gs/libpng/pngwutil.c b/gs/libpng/pngwutil.c
new file mode 100644
index 000000000..dd7b150b7
--- /dev/null
+++ b/gs/libpng/pngwutil.c
@@ -0,0 +1,2730 @@
+
+/* pngwutil.c - utilities to write a PNG file
+ *
+ * libpng version 1.2.8 - December 3, 2004
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+#ifdef PNG_WRITE_SUPPORTED
+
+/* Place a 32-bit number into a buffer in PNG byte order.  We work
+ * with unsigned numbers for convenience, although one supported
+ * ancillary chunk uses signed (two's complement) numbers.
+ */
+void /* PRIVATE */
+png_save_uint_32(png_bytep buf, png_uint_32 i)
+{
+   buf[0] = (png_byte)((i >> 24) & 0xff);
+   buf[1] = (png_byte)((i >> 16) & 0xff);
+   buf[2] = (png_byte)((i >> 8) & 0xff);
+   buf[3] = (png_byte)(i & 0xff);
+}
+
+#if defined(PNG_WRITE_pCAL_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
+/* The png_save_int_32 function assumes integers are stored in two's
+ * complement format.  If this isn't the case, then this routine needs to
+ * be modified to write data in two's complement format.
+ */
+void /* PRIVATE */
+png_save_int_32(png_bytep buf, png_int_32 i)
+{
+   buf[0] = (png_byte)((i >> 24) & 0xff);
+   buf[1] = (png_byte)((i >> 16) & 0xff);
+   buf[2] = (png_byte)((i >> 8) & 0xff);
+   buf[3] = (png_byte)(i & 0xff);
+}
+#endif
+
+/* Place a 16-bit number into a buffer in PNG byte order.
+ * The parameter is declared unsigned int, not png_uint_16,
+ * just to avoid potential problems on pre-ANSI C compilers.
+ */
+void /* PRIVATE */
+png_save_uint_16(png_bytep buf, unsigned int i)
+{
+   buf[0] = (png_byte)((i >> 8) & 0xff);
+   buf[1] = (png_byte)(i & 0xff);
+}
+
+/* Write a PNG chunk all at once.  The type is an array of ASCII characters
+ * representing the chunk name.  The array must be at least 4 bytes in
+ * length, and does not need to be null terminated.  To be safe, pass the
+ * pre-defined chunk names here, and if you need a new one, define it
+ * where the others are defined.  The length is the length of the data.
+ * All the data must be present.  If that is not possible, use the
+ * png_write_chunk_start(), png_write_chunk_data(), and png_write_chunk_end()
+ * functions instead.
+ */
+void PNGAPI
+png_write_chunk(png_structp png_ptr, png_bytep chunk_name,
+   png_bytep data, png_size_t length)
+{
+   png_write_chunk_start(png_ptr, chunk_name, (png_uint_32)length);
+   png_write_chunk_data(png_ptr, data, length);
+   png_write_chunk_end(png_ptr);
+}
+
+/* Write the start of a PNG chunk.  The type is the chunk type.
+ * The total_length is the sum of the lengths of all the data you will be
+ * passing in png_write_chunk_data().
+ */
+void PNGAPI
+png_write_chunk_start(png_structp png_ptr, png_bytep chunk_name,
+   png_uint_32 length)
+{
+   png_byte buf[4];
+   png_debug2(0, "Writing %s chunk (%lu bytes)\n", chunk_name, length);
+
+   /* write the length */
+   png_save_uint_32(buf, length);
+   png_write_data(png_ptr, buf, (png_size_t)4);
+
+   /* write the chunk name */
+   png_write_data(png_ptr, chunk_name, (png_size_t)4);
+   /* reset the crc and run it over the chunk name */
+   png_reset_crc(png_ptr);
+   png_calculate_crc(png_ptr, chunk_name, (png_size_t)4);
+}
+
+/* Write the data of a PNG chunk started with png_write_chunk_start().
+ * Note that multiple calls to this function are allowed, and that the
+ * sum of the lengths from these calls *must* add up to the total_length
+ * given to png_write_chunk_start().
+ */
+void PNGAPI
+png_write_chunk_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   /* write the data, and run the CRC over it */
+   if (data != NULL && length > 0)
+   {
+      png_calculate_crc(png_ptr, data, length);
+      png_write_data(png_ptr, data, length);
+   }
+}
+
+/* Finish a chunk started with png_write_chunk_start(). */
+void PNGAPI
+png_write_chunk_end(png_structp png_ptr)
+{
+   png_byte buf[4];
+
+   /* write the crc */
+   png_save_uint_32(buf, png_ptr->crc);
+
+   png_write_data(png_ptr, buf, (png_size_t)4);
+}
+
+/* Simple function to write the signature.  If we have already written
+ * the magic bytes of the signature, or more likely, the PNG stream is
+ * being embedded into another stream and doesn't need its own signature,
+ * we should call png_set_sig_bytes() to tell libpng how many of the
+ * bytes have already been written.
+ */
+void /* PRIVATE */
+png_write_sig(png_structp png_ptr)
+{
+   png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
+   /* write the rest of the 8 byte signature */
+   png_write_data(png_ptr, &png_signature[png_ptr->sig_bytes],
+      (png_size_t)8 - png_ptr->sig_bytes);
+   if(png_ptr->sig_bytes < 3)
+      png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
+}
+
+#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_iCCP_SUPPORTED)
+/*
+ * This pair of functions encapsulates the operation of (a) compressing a
+ * text string, and (b) issuing it later as a series of chunk data writes.
+ * The compression_state structure is shared context for these functions
+ * set up by the caller in order to make the whole mess thread-safe.
+ */
+
+typedef struct
+{
+    char *input;   /* the uncompressed input data */
+    int input_len;   /* its length */
+    int num_output_ptr; /* number of output pointers used */
+    int max_output_ptr; /* size of output_ptr */
+    png_charpp output_ptr; /* array of pointers to output */
+} compression_state;
+
+/* compress given text into storage in the png_ptr structure */
+static int /* PRIVATE */
+png_text_compress(png_structp png_ptr,
+        png_charp text, png_size_t text_len, int compression,
+        compression_state *comp)
+{
+   int ret;
+
+   comp->num_output_ptr = comp->max_output_ptr = 0;
+   comp->output_ptr = NULL;
+   comp->input = NULL;
+
+   /* we may just want to pass the text right through */
+   if (compression == PNG_TEXT_COMPRESSION_NONE)
+   {
+       comp->input = text;
+       comp->input_len = text_len;
+       return((int)text_len);
+   }
+
+   if (compression >= PNG_TEXT_COMPRESSION_LAST)
+   {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+      char msg[50];
+      sprintf(msg, "Unknown compression type %d", compression);
+      png_warning(png_ptr, msg);
+#else
+      png_warning(png_ptr, "Unknown compression type");
+#endif
+   }
+
+   /* We can't write the chunk until we find out how much data we have,
+    * which means we need to run the compressor first and save the
+    * output.  This shouldn't be a problem, as the vast majority of
+    * comments should be reasonable, but we will set up an array of
+    * malloc'd pointers to be sure.
+    *
+    * If we knew the application was well behaved, we could simplify this
+    * greatly by assuming we can always malloc an output buffer large
+    * enough to hold the compressed text ((1001 * text_len / 1000) + 12)
+    * and malloc this directly.  The only time this would be a bad idea is
+    * if we can't malloc more than 64K and we have 64K of random input
+    * data, or if the input string is incredibly large (although this
+    * wouldn't cause a failure, just a slowdown due to swapping).
+    */
+
+   /* set up the compression buffers */
+   png_ptr->zstream.avail_in = (uInt)text_len;
+   png_ptr->zstream.next_in = (Bytef *)text;
+   png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+   png_ptr->zstream.next_out = (Bytef *)png_ptr->zbuf;
+
+   /* this is the same compression loop as in png_write_row() */
+   do
+   {
+      /* compress the data */
+      ret = deflate(&png_ptr->zstream, Z_NO_FLUSH);
+      if (ret != Z_OK)
+      {
+         /* error */
+         if (png_ptr->zstream.msg != NULL)
+            png_error(png_ptr, png_ptr->zstream.msg);
+         else
+            png_error(png_ptr, "zlib error");
+      }
+      /* check to see if we need more room */
+      if (!(png_ptr->zstream.avail_out))
+      {
+         /* make sure the output array has room */
+         if (comp->num_output_ptr >= comp->max_output_ptr)
+         {
+            int old_max;
+
+            old_max = comp->max_output_ptr;
+            comp->max_output_ptr = comp->num_output_ptr + 4;
+            if (comp->output_ptr != NULL)
+            {
+               png_charpp old_ptr;
+
+               old_ptr = comp->output_ptr;
+               comp->output_ptr = (png_charpp)png_malloc(png_ptr,
+                  (png_uint_32)(comp->max_output_ptr *
+                  png_sizeof (png_charpp)));
+               png_memcpy(comp->output_ptr, old_ptr, old_max
+                  * png_sizeof (png_charp));
+               png_free(png_ptr, old_ptr);
+            }
+            else
+               comp->output_ptr = (png_charpp)png_malloc(png_ptr,
+                  (png_uint_32)(comp->max_output_ptr *
+                  png_sizeof (png_charp)));
+         }
+
+         /* save the data */
+         comp->output_ptr[comp->num_output_ptr] = (png_charp)png_malloc(png_ptr,
+            (png_uint_32)png_ptr->zbuf_size);
+         png_memcpy(comp->output_ptr[comp->num_output_ptr], png_ptr->zbuf,
+            png_ptr->zbuf_size);
+         comp->num_output_ptr++;
+
+         /* and reset the buffer */
+         png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+         png_ptr->zstream.next_out = png_ptr->zbuf;
+      }
+   /* continue until we don't have any more to compress */
+   } while (png_ptr->zstream.avail_in);
+
+   /* finish the compression */
+   do
+   {
+      /* tell zlib we are finished */
+      ret = deflate(&png_ptr->zstream, Z_FINISH);
+
+      if (ret == Z_OK)
+      {
+         /* check to see if we need more room */
+         if (!(png_ptr->zstream.avail_out))
+         {
+            /* check to make sure our output array has room */
+            if (comp->num_output_ptr >= comp->max_output_ptr)
+            {
+               int old_max;
+
+               old_max = comp->max_output_ptr;
+               comp->max_output_ptr = comp->num_output_ptr + 4;
+               if (comp->output_ptr != NULL)
+               {
+                  png_charpp old_ptr;
+
+                  old_ptr = comp->output_ptr;
+                  /* This could be optimized to realloc() */
+                  comp->output_ptr = (png_charpp)png_malloc(png_ptr,
+                     (png_uint_32)(comp->max_output_ptr *
+                     png_sizeof (png_charpp)));
+                  png_memcpy(comp->output_ptr, old_ptr,
+                     old_max * png_sizeof (png_charp));
+                  png_free(png_ptr, old_ptr);
+               }
+               else
+                  comp->output_ptr = (png_charpp)png_malloc(png_ptr,
+                     (png_uint_32)(comp->max_output_ptr *
+                     png_sizeof (png_charp)));
+            }
+
+            /* save off the data */
+            comp->output_ptr[comp->num_output_ptr] =
+               (png_charp)png_malloc(png_ptr, (png_uint_32)png_ptr->zbuf_size);
+            png_memcpy(comp->output_ptr[comp->num_output_ptr], png_ptr->zbuf,
+               png_ptr->zbuf_size);
+            comp->num_output_ptr++;
+
+            /* and reset the buffer pointers */
+            png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+            png_ptr->zstream.next_out = png_ptr->zbuf;
+         }
+      }
+      else if (ret != Z_STREAM_END)
+      {
+         /* we got an error */
+         if (png_ptr->zstream.msg != NULL)
+            png_error(png_ptr, png_ptr->zstream.msg);
+         else
+            png_error(png_ptr, "zlib error");
+      }
+   } while (ret != Z_STREAM_END);
+
+   /* text length is number of buffers plus last buffer */
+   text_len = png_ptr->zbuf_size * comp->num_output_ptr;
+   if (png_ptr->zstream.avail_out < png_ptr->zbuf_size)
+      text_len += png_ptr->zbuf_size - (png_size_t)png_ptr->zstream.avail_out;
+
+   return((int)text_len);
+}
+
+/* ship the compressed text out via chunk writes */
+static void /* PRIVATE */
+png_write_compressed_data_out(png_structp png_ptr, compression_state *comp)
+{
+   int i;
+
+   /* handle the no-compression case */
+   if (comp->input)
+   {
+       png_write_chunk_data(png_ptr, (png_bytep)comp->input,
+                            (png_size_t)comp->input_len);
+       return;
+   }
+
+   /* write saved output buffers, if any */
+   for (i = 0; i < comp->num_output_ptr; i++)
+   {
+      png_write_chunk_data(png_ptr,(png_bytep)comp->output_ptr[i],
+         png_ptr->zbuf_size);
+      png_free(png_ptr, comp->output_ptr[i]);
+      comp->output_ptr[i]=NULL;
+   }
+   if (comp->max_output_ptr != 0)
+      png_free(png_ptr, comp->output_ptr);
+      comp->output_ptr=NULL;
+   /* write anything left in zbuf */
+   if (png_ptr->zstream.avail_out < (png_uint_32)png_ptr->zbuf_size)
+      png_write_chunk_data(png_ptr, png_ptr->zbuf,
+         png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+
+   /* reset zlib for another zTXt/iTXt or image data */
+   deflateReset(&png_ptr->zstream);
+   png_ptr->zstream.data_type = Z_BINARY;
+}
+#endif
+
+/* Write the IHDR chunk, and update the png_struct with the necessary
+ * information.  Note that the rest of this code depends upon this
+ * information being correct.
+ */
+void /* PRIVATE */
+png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
+   int bit_depth, int color_type, int compression_type, int filter_type,
+   int interlace_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_IHDR;
+#endif
+   png_byte buf[13]; /* buffer to store the IHDR info */
+
+   png_debug(1, "in png_write_IHDR\n");
+   /* Check that we have valid input data from the application info */
+   switch (color_type)
+   {
+      case PNG_COLOR_TYPE_GRAY:
+         switch (bit_depth)
+         {
+            case 1:
+            case 2:
+            case 4:
+            case 8:
+            case 16: png_ptr->channels = 1; break;
+            default: png_error(png_ptr,"Invalid bit depth for grayscale image");
+         }
+         break;
+      case PNG_COLOR_TYPE_RGB:
+         if (bit_depth != 8 && bit_depth != 16)
+            png_error(png_ptr, "Invalid bit depth for RGB image");
+         png_ptr->channels = 3;
+         break;
+      case PNG_COLOR_TYPE_PALETTE:
+         switch (bit_depth)
+         {
+            case 1:
+            case 2:
+            case 4:
+            case 8: png_ptr->channels = 1; break;
+            default: png_error(png_ptr, "Invalid bit depth for paletted image");
+         }
+         break;
+      case PNG_COLOR_TYPE_GRAY_ALPHA:
+         if (bit_depth != 8 && bit_depth != 16)
+            png_error(png_ptr, "Invalid bit depth for grayscale+alpha image");
+         png_ptr->channels = 2;
+         break;
+      case PNG_COLOR_TYPE_RGB_ALPHA:
+         if (bit_depth != 8 && bit_depth != 16)
+            png_error(png_ptr, "Invalid bit depth for RGBA image");
+         png_ptr->channels = 4;
+         break;
+      default:
+         png_error(png_ptr, "Invalid image color type specified");
+   }
+
+   if (compression_type != PNG_COMPRESSION_TYPE_BASE)
+   {
+      png_warning(png_ptr, "Invalid compression type specified");
+      compression_type = PNG_COMPRESSION_TYPE_BASE;
+   }
+
+   /* Write filter_method 64 (intrapixel differencing) only if
+    * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
+    * 2. Libpng did not write a PNG signature (this filter_method is only
+    *    used in PNG datastreams that are embedded in MNG datastreams) and
+    * 3. The application called png_permit_mng_features with a mask that
+    *    included PNG_FLAG_MNG_FILTER_64 and
+    * 4. The filter_method is 64 and
+    * 5. The color_type is RGB or RGBA
+    */
+   if (
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+      !((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+      ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
+      (color_type == PNG_COLOR_TYPE_RGB ||
+       color_type == PNG_COLOR_TYPE_RGB_ALPHA) &&
+      (filter_type == PNG_INTRAPIXEL_DIFFERENCING)) &&
+#endif
+      filter_type != PNG_FILTER_TYPE_BASE)
+   {
+      png_warning(png_ptr, "Invalid filter type specified");
+      filter_type = PNG_FILTER_TYPE_BASE;
+   }
+
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+   if (interlace_type != PNG_INTERLACE_NONE &&
+      interlace_type != PNG_INTERLACE_ADAM7)
+   {
+      png_warning(png_ptr, "Invalid interlace type specified");
+      interlace_type = PNG_INTERLACE_ADAM7;
+   }
+#else
+   interlace_type=PNG_INTERLACE_NONE;
+#endif
+
+   /* save off the relevent information */
+   png_ptr->bit_depth = (png_byte)bit_depth;
+   png_ptr->color_type = (png_byte)color_type;
+   png_ptr->interlaced = (png_byte)interlace_type;
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+   png_ptr->filter_type = (png_byte)filter_type;
+#endif
+   png_ptr->compression_type = (png_byte)compression_type;
+   png_ptr->width = width;
+   png_ptr->height = height;
+
+   png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels);
+   png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, width);
+   /* set the usr info, so any transformations can modify it */
+   png_ptr->usr_width = png_ptr->width;
+   png_ptr->usr_bit_depth = png_ptr->bit_depth;
+   png_ptr->usr_channels = png_ptr->channels;
+
+   /* pack the header information into the buffer */
+   png_save_uint_32(buf, width);
+   png_save_uint_32(buf + 4, height);
+   buf[8] = (png_byte)bit_depth;
+   buf[9] = (png_byte)color_type;
+   buf[10] = (png_byte)compression_type;
+   buf[11] = (png_byte)filter_type;
+   buf[12] = (png_byte)interlace_type;
+
+   /* write the chunk */
+   png_write_chunk(png_ptr, (png_bytep)png_IHDR, buf, (png_size_t)13);
+
+   /* initialize zlib with PNG info */
+   png_ptr->zstream.zalloc = png_zalloc;
+   png_ptr->zstream.zfree = png_zfree;
+   png_ptr->zstream.opaque = (voidpf)png_ptr;
+   if (!(png_ptr->do_filter))
+   {
+      if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE ||
+         png_ptr->bit_depth < 8)
+         png_ptr->do_filter = PNG_FILTER_NONE;
+      else
+         png_ptr->do_filter = PNG_ALL_FILTERS;
+   }
+   if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY))
+   {
+      if (png_ptr->do_filter != PNG_FILTER_NONE)
+         png_ptr->zlib_strategy = Z_FILTERED;
+      else
+         png_ptr->zlib_strategy = Z_DEFAULT_STRATEGY;
+   }
+   if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_LEVEL))
+      png_ptr->zlib_level = Z_DEFAULT_COMPRESSION;
+   if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL))
+      png_ptr->zlib_mem_level = 8;
+   if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS))
+      png_ptr->zlib_window_bits = 15;
+   if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_METHOD))
+      png_ptr->zlib_method = 8;
+   deflateInit2(&png_ptr->zstream, png_ptr->zlib_level,
+      png_ptr->zlib_method, png_ptr->zlib_window_bits,
+      png_ptr->zlib_mem_level, png_ptr->zlib_strategy);
+   png_ptr->zstream.next_out = png_ptr->zbuf;
+   png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+   /* libpng is not interested in zstream.data_type */
+   /* set it to a predefined value, to avoid its evaluation inside zlib */
+   png_ptr->zstream.data_type = Z_BINARY;
+
+   png_ptr->mode = PNG_HAVE_IHDR;
+}
+
+/* write the palette.  We are careful not to trust png_color to be in the
+ * correct order for PNG, so people can redefine it to any convenient
+ * structure.
+ */
+void /* PRIVATE */
+png_write_PLTE(png_structp png_ptr, png_colorp palette, png_uint_32 num_pal)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_PLTE;
+#endif
+   png_uint_32 i;
+   png_colorp pal_ptr;
+   png_byte buf[3];
+
+   png_debug(1, "in png_write_PLTE\n");
+   if ((
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+        !(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) &&
+#endif
+        num_pal == 0) || num_pal > 256)
+   {
+     if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+     {
+        png_error(png_ptr, "Invalid number of colors in palette");
+     }
+     else
+     {
+        png_warning(png_ptr, "Invalid number of colors in palette");
+        return;
+     }
+   }
+
+   if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR))
+   {
+      png_warning(png_ptr,
+        "Ignoring request to write a PLTE chunk in grayscale PNG");
+      return;
+   }
+
+   png_ptr->num_palette = (png_uint_16)num_pal;
+   png_debug1(3, "num_palette = %d\n", png_ptr->num_palette);
+
+   png_write_chunk_start(png_ptr, (png_bytep)png_PLTE, num_pal * 3);
+#ifndef PNG_NO_POINTER_INDEXING
+   for (i = 0, pal_ptr = palette; i < num_pal; i++, pal_ptr++)
+   {
+      buf[0] = pal_ptr->red;
+      buf[1] = pal_ptr->green;
+      buf[2] = pal_ptr->blue;
+      png_write_chunk_data(png_ptr, buf, (png_size_t)3);
+   }
+#else
+   /* This is a little slower but some buggy compilers need to do this instead */
+   pal_ptr=palette;
+   for (i = 0; i < num_pal; i++)
+   {
+      buf[0] = pal_ptr[i].red;
+      buf[1] = pal_ptr[i].green;
+      buf[2] = pal_ptr[i].blue;
+      png_write_chunk_data(png_ptr, buf, (png_size_t)3);
+   }
+#endif
+   png_write_chunk_end(png_ptr);
+   png_ptr->mode |= PNG_HAVE_PLTE;
+}
+
+/* write an IDAT chunk */
+void /* PRIVATE */
+png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_IDAT;
+#endif
+   png_debug(1, "in png_write_IDAT\n");
+
+   /* Optimize the CMF field in the zlib stream. */
+   /* This hack of the zlib stream is compliant to the stream specification. */
+   if (!(png_ptr->mode & PNG_HAVE_IDAT) &&
+       png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
+   {
+      unsigned int z_cmf = data[0];  /* zlib compression method and flags */
+      if ((z_cmf & 0x0f) == 8 && (z_cmf & 0xf0) <= 0x70)
+      {
+         /* Avoid memory underflows and multiplication overflows. */
+         /* The conditions below are practically always satisfied;
+            however, they still must be checked. */
+         if (length >= 2 &&
+             png_ptr->height < 16384 && png_ptr->width < 16384)
+         {
+            png_uint_32 uncompressed_idat_size = png_ptr->height *
+               ((png_ptr->width *
+               png_ptr->channels * png_ptr->bit_depth + 15) >> 3);
+            unsigned int z_cinfo = z_cmf >> 4;
+            unsigned int half_z_window_size = 1 << (z_cinfo + 7);
+            while (uncompressed_idat_size <= half_z_window_size &&
+                   half_z_window_size >= 256)
+            {
+               z_cinfo--;
+               half_z_window_size >>= 1;
+            }
+            z_cmf = (z_cmf & 0x0f) | (z_cinfo << 4);
+            if (data[0] != (png_byte)z_cmf)
+            {
+               data[0] = (png_byte)z_cmf;
+               data[1] &= 0xe0;
+               data[1] += (png_byte)(0x1f - ((z_cmf << 8) + data[1]) % 0x1f);
+            }
+         }
+      }
+      else
+         png_error(png_ptr,
+            "Invalid zlib compression method or flags in IDAT");
+   }
+
+   png_write_chunk(png_ptr, (png_bytep)png_IDAT, data, length);
+   png_ptr->mode |= PNG_HAVE_IDAT;
+}
+
+/* write an IEND chunk */
+void /* PRIVATE */
+png_write_IEND(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_IEND;
+#endif
+   png_debug(1, "in png_write_IEND\n");
+   png_write_chunk(png_ptr, (png_bytep)png_IEND, png_bytep_NULL,
+     (png_size_t)0);
+   png_ptr->mode |= PNG_HAVE_IEND;
+}
+
+#if defined(PNG_WRITE_gAMA_SUPPORTED)
+/* write a gAMA chunk */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void /* PRIVATE */
+png_write_gAMA(png_structp png_ptr, double file_gamma)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_gAMA;
+#endif
+   png_uint_32 igamma;
+   png_byte buf[4];
+
+   png_debug(1, "in png_write_gAMA\n");
+   /* file_gamma is saved in 1/100,000ths */
+   igamma = (png_uint_32)(file_gamma * 100000.0 + 0.5);
+   png_save_uint_32(buf, igamma);
+   png_write_chunk(png_ptr, (png_bytep)png_gAMA, buf, (png_size_t)4);
+}
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void /* PRIVATE */
+png_write_gAMA_fixed(png_structp png_ptr, png_fixed_point file_gamma)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_gAMA;
+#endif
+   png_byte buf[4];
+
+   png_debug(1, "in png_write_gAMA\n");
+   /* file_gamma is saved in 1/100,000ths */
+   png_save_uint_32(buf, (png_uint_32)file_gamma);
+   png_write_chunk(png_ptr, (png_bytep)png_gAMA, buf, (png_size_t)4);
+}
+#endif
+#endif
+
+#if defined(PNG_WRITE_sRGB_SUPPORTED)
+/* write a sRGB chunk */
+void /* PRIVATE */
+png_write_sRGB(png_structp png_ptr, int srgb_intent)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_sRGB;
+#endif
+   png_byte buf[1];
+
+   png_debug(1, "in png_write_sRGB\n");
+   if(srgb_intent >= PNG_sRGB_INTENT_LAST)
+         png_warning(png_ptr,
+            "Invalid sRGB rendering intent specified");
+   buf[0]=(png_byte)srgb_intent;
+   png_write_chunk(png_ptr, (png_bytep)png_sRGB, buf, (png_size_t)1);
+}
+#endif
+
+#if defined(PNG_WRITE_iCCP_SUPPORTED)
+/* write an iCCP chunk */
+void /* PRIVATE */
+png_write_iCCP(png_structp png_ptr, png_charp name, int compression_type,
+   png_charp profile, int profile_len)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_iCCP;
+#endif
+   png_size_t name_len;
+   png_charp new_name;
+   compression_state comp;
+
+   png_debug(1, "in png_write_iCCP\n");
+   if (name == NULL || (name_len = png_check_keyword(png_ptr, name,
+      &new_name)) == 0)
+   {
+      png_warning(png_ptr, "Empty keyword in iCCP chunk");
+      return;
+   }
+
+   if (compression_type != PNG_COMPRESSION_TYPE_BASE)
+      png_warning(png_ptr, "Unknown compression type in iCCP chunk");
+
+   if (profile == NULL)
+      profile_len = 0;
+
+   if (profile_len)
+       profile_len = png_text_compress(png_ptr, profile, (png_size_t)profile_len,
+          PNG_COMPRESSION_TYPE_BASE, &comp);
+
+   /* make sure we include the NULL after the name and the compression type */
+   png_write_chunk_start(png_ptr, (png_bytep)png_iCCP,
+          (png_uint_32)name_len+profile_len+2);
+   new_name[name_len+1]=0x00;
+   png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 2);
+
+   if (profile_len)
+      png_write_compressed_data_out(png_ptr, &comp);
+
+   png_write_chunk_end(png_ptr);
+   png_free(png_ptr, new_name);
+}
+#endif
+
+#if defined(PNG_WRITE_sPLT_SUPPORTED)
+/* write a sPLT chunk */
+void /* PRIVATE */
+png_write_sPLT(png_structp png_ptr, png_sPLT_tp spalette)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_sPLT;
+#endif
+   png_size_t name_len;
+   png_charp new_name;
+   png_byte entrybuf[10];
+   int entry_size = (spalette->depth == 8 ? 6 : 10);
+   int palette_size = entry_size * spalette->nentries;
+   png_sPLT_entryp ep;
+#ifdef PNG_NO_POINTER_INDEXING
+   int i;
+#endif
+
+   png_debug(1, "in png_write_sPLT\n");
+   if (spalette->name == NULL || (name_len = png_check_keyword(png_ptr,
+      spalette->name, &new_name))==0)
+   {
+      png_warning(png_ptr, "Empty keyword in sPLT chunk");
+      return;
+   }
+
+   /* make sure we include the NULL after the name */
+   png_write_chunk_start(png_ptr, (png_bytep)png_sPLT,
+          (png_uint_32)(name_len + 2 + palette_size));
+   png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 1);
+   png_write_chunk_data(png_ptr, (png_bytep)&spalette->depth, 1);
+
+   /* loop through each palette entry, writing appropriately */
+#ifndef PNG_NO_POINTER_INDEXING
+   for (ep = spalette->entries; ep<spalette->entries+spalette->nentries; ep++)
+   {
+       if (spalette->depth == 8)
+       {
+           entrybuf[0] = (png_byte)ep->red;
+           entrybuf[1] = (png_byte)ep->green;
+           entrybuf[2] = (png_byte)ep->blue;
+           entrybuf[3] = (png_byte)ep->alpha;
+           png_save_uint_16(entrybuf + 4, ep->frequency);
+       }
+       else
+       {
+           png_save_uint_16(entrybuf + 0, ep->red);
+           png_save_uint_16(entrybuf + 2, ep->green);
+           png_save_uint_16(entrybuf + 4, ep->blue);
+           png_save_uint_16(entrybuf + 6, ep->alpha);
+           png_save_uint_16(entrybuf + 8, ep->frequency);
+       }
+       png_write_chunk_data(png_ptr, entrybuf, (png_size_t)entry_size);
+   }
+#else
+   ep=spalette->entries;
+   for (i=0; i>spalette->nentries; i++)
+   {
+       if (spalette->depth == 8)
+       {
+           entrybuf[0] = (png_byte)ep[i].red;
+           entrybuf[1] = (png_byte)ep[i].green;
+           entrybuf[2] = (png_byte)ep[i].blue;
+           entrybuf[3] = (png_byte)ep[i].alpha;
+           png_save_uint_16(entrybuf + 4, ep[i].frequency);
+       }
+       else
+       {
+           png_save_uint_16(entrybuf + 0, ep[i].red);
+           png_save_uint_16(entrybuf + 2, ep[i].green);
+           png_save_uint_16(entrybuf + 4, ep[i].blue);
+           png_save_uint_16(entrybuf + 6, ep[i].alpha);
+           png_save_uint_16(entrybuf + 8, ep[i].frequency);
+       }
+       png_write_chunk_data(png_ptr, entrybuf, entry_size);
+   }
+#endif
+
+   png_write_chunk_end(png_ptr);
+   png_free(png_ptr, new_name);
+}
+#endif
+
+#if defined(PNG_WRITE_sBIT_SUPPORTED)
+/* write the sBIT chunk */
+void /* PRIVATE */
+png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_sBIT;
+#endif
+   png_byte buf[4];
+   png_size_t size;
+
+   png_debug(1, "in png_write_sBIT\n");
+   /* make sure we don't depend upon the order of PNG_COLOR_8 */
+   if (color_type & PNG_COLOR_MASK_COLOR)
+   {
+      png_byte maxbits;
+
+      maxbits = (png_byte)(color_type==PNG_COLOR_TYPE_PALETTE ? 8 :
+                png_ptr->usr_bit_depth);
+      if (sbit->red == 0 || sbit->red > maxbits ||
+          sbit->green == 0 || sbit->green > maxbits ||
+          sbit->blue == 0 || sbit->blue > maxbits)
+      {
+         png_warning(png_ptr, "Invalid sBIT depth specified");
+         return;
+      }
+      buf[0] = sbit->red;
+      buf[1] = sbit->green;
+      buf[2] = sbit->blue;
+      size = 3;
+   }
+   else
+   {
+      if (sbit->gray == 0 || sbit->gray > png_ptr->usr_bit_depth)
+      {
+         png_warning(png_ptr, "Invalid sBIT depth specified");
+         return;
+      }
+      buf[0] = sbit->gray;
+      size = 1;
+   }
+
+   if (color_type & PNG_COLOR_MASK_ALPHA)
+   {
+      if (sbit->alpha == 0 || sbit->alpha > png_ptr->usr_bit_depth)
+      {
+         png_warning(png_ptr, "Invalid sBIT depth specified");
+         return;
+      }
+      buf[size++] = sbit->alpha;
+   }
+
+   png_write_chunk(png_ptr, (png_bytep)png_sBIT, buf, size);
+}
+#endif
+
+#if defined(PNG_WRITE_cHRM_SUPPORTED)
+/* write the cHRM chunk */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void /* PRIVATE */
+png_write_cHRM(png_structp png_ptr, double white_x, double white_y,
+   double red_x, double red_y, double green_x, double green_y,
+   double blue_x, double blue_y)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_cHRM;
+#endif
+   png_byte buf[32];
+   png_uint_32 itemp;
+
+   png_debug(1, "in png_write_cHRM\n");
+   /* each value is saved in 1/100,000ths */
+   if (white_x < 0 || white_x > 0.8 || white_y < 0 || white_y > 0.8 ||
+       white_x + white_y > 1.0)
+   {
+      png_warning(png_ptr, "Invalid cHRM white point specified");
+#if !defined(PNG_NO_CONSOLE_IO)
+      fprintf(stderr,"white_x=%f, white_y=%f\n",white_x, white_y);
+#endif
+      return;
+   }
+   itemp = (png_uint_32)(white_x * 100000.0 + 0.5);
+   png_save_uint_32(buf, itemp);
+   itemp = (png_uint_32)(white_y * 100000.0 + 0.5);
+   png_save_uint_32(buf + 4, itemp);
+
+   if (red_x < 0 || red_x > 0.8 || red_y < 0 || red_y > 0.8 ||
+       red_x + red_y > 1.0)
+   {
+      png_warning(png_ptr, "Invalid cHRM red point specified");
+      return;
+   }
+   itemp = (png_uint_32)(red_x * 100000.0 + 0.5);
+   png_save_uint_32(buf + 8, itemp);
+   itemp = (png_uint_32)(red_y * 100000.0 + 0.5);
+   png_save_uint_32(buf + 12, itemp);
+
+   if (green_x < 0 || green_x > 0.8 || green_y < 0 || green_y > 0.8 ||
+       green_x + green_y > 1.0)
+   {
+      png_warning(png_ptr, "Invalid cHRM green point specified");
+      return;
+   }
+   itemp = (png_uint_32)(green_x * 100000.0 + 0.5);
+   png_save_uint_32(buf + 16, itemp);
+   itemp = (png_uint_32)(green_y * 100000.0 + 0.5);
+   png_save_uint_32(buf + 20, itemp);
+
+   if (blue_x < 0 || blue_x > 0.8 || blue_y < 0 || blue_y > 0.8 ||
+       blue_x + blue_y > 1.0)
+   {
+      png_warning(png_ptr, "Invalid cHRM blue point specified");
+      return;
+   }
+   itemp = (png_uint_32)(blue_x * 100000.0 + 0.5);
+   png_save_uint_32(buf + 24, itemp);
+   itemp = (png_uint_32)(blue_y * 100000.0 + 0.5);
+   png_save_uint_32(buf + 28, itemp);
+
+   png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32);
+}
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void /* PRIVATE */
+png_write_cHRM_fixed(png_structp png_ptr, png_fixed_point white_x,
+   png_fixed_point white_y, png_fixed_point red_x, png_fixed_point red_y,
+   png_fixed_point green_x, png_fixed_point green_y, png_fixed_point blue_x,
+   png_fixed_point blue_y)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_cHRM;
+#endif
+   png_byte buf[32];
+
+   png_debug(1, "in png_write_cHRM\n");
+   /* each value is saved in 1/100,000ths */
+   if (white_x > 80000L || white_y > 80000L || white_x + white_y > 100000L)
+   {
+      png_warning(png_ptr, "Invalid fixed cHRM white point specified");
+#if !defined(PNG_NO_CONSOLE_IO)
+      fprintf(stderr,"white_x=%ld, white_y=%ld\n",white_x, white_y);
+#endif
+      return;
+   }
+   png_save_uint_32(buf, (png_uint_32)white_x);
+   png_save_uint_32(buf + 4, (png_uint_32)white_y);
+
+   if (red_x > 80000L || red_y > 80000L || red_x + red_y > 100000L)
+   {
+      png_warning(png_ptr, "Invalid cHRM fixed red point specified");
+      return;
+   }
+   png_save_uint_32(buf + 8, (png_uint_32)red_x);
+   png_save_uint_32(buf + 12, (png_uint_32)red_y);
+
+   if (green_x > 80000L || green_y > 80000L || green_x + green_y > 100000L)
+   {
+      png_warning(png_ptr, "Invalid fixed cHRM green point specified");
+      return;
+   }
+   png_save_uint_32(buf + 16, (png_uint_32)green_x);
+   png_save_uint_32(buf + 20, (png_uint_32)green_y);
+
+   if (blue_x > 80000L || blue_y > 80000L || blue_x + blue_y > 100000L)
+   {
+      png_warning(png_ptr, "Invalid fixed cHRM blue point specified");
+      return;
+   }
+   png_save_uint_32(buf + 24, (png_uint_32)blue_x);
+   png_save_uint_32(buf + 28, (png_uint_32)blue_y);
+
+   png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32);
+}
+#endif
+#endif
+
+#if defined(PNG_WRITE_tRNS_SUPPORTED)
+/* write the tRNS chunk */
+void /* PRIVATE */
+png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran,
+   int num_trans, int color_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_tRNS;
+#endif
+   png_byte buf[6];
+
+   png_debug(1, "in png_write_tRNS\n");
+   if (color_type == PNG_COLOR_TYPE_PALETTE)
+   {
+      if (num_trans <= 0 || num_trans > (int)png_ptr->num_palette)
+      {
+         png_warning(png_ptr,"Invalid number of transparent colors specified");
+         return;
+      }
+      /* write the chunk out as it is */
+      png_write_chunk(png_ptr, (png_bytep)png_tRNS, trans, (png_size_t)num_trans);
+   }
+   else if (color_type == PNG_COLOR_TYPE_GRAY)
+   {
+      /* one 16 bit value */
+      if(tran->gray >= (1 << png_ptr->bit_depth))
+      {
+         png_warning(png_ptr,
+           "Ignoring attempt to write tRNS chunk out-of-range for bit_depth");
+         return;
+      }
+      png_save_uint_16(buf, tran->gray);
+      png_write_chunk(png_ptr, (png_bytep)png_tRNS, buf, (png_size_t)2);
+   }
+   else if (color_type == PNG_COLOR_TYPE_RGB)
+   {
+      /* three 16 bit values */
+      png_save_uint_16(buf, tran->red);
+      png_save_uint_16(buf + 2, tran->green);
+      png_save_uint_16(buf + 4, tran->blue);
+      if(png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]))
+         {
+            png_warning(png_ptr,
+              "Ignoring attempt to write 16-bit tRNS chunk when bit_depth is 8");
+            return;
+         }
+      png_write_chunk(png_ptr, (png_bytep)png_tRNS, buf, (png_size_t)6);
+   }
+   else
+   {
+      png_warning(png_ptr, "Can't write tRNS with an alpha channel");
+   }
+}
+#endif
+
+#if defined(PNG_WRITE_bKGD_SUPPORTED)
+/* write the background chunk */
+void /* PRIVATE */
+png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_bKGD;
+#endif
+   png_byte buf[6];
+
+   png_debug(1, "in png_write_bKGD\n");
+   if (color_type == PNG_COLOR_TYPE_PALETTE)
+   {
+      if (
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+          (png_ptr->num_palette ||
+          (!(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE))) &&
+#endif
+         back->index > png_ptr->num_palette)
+      {
+         png_warning(png_ptr, "Invalid background palette index");
+         return;
+      }
+      buf[0] = back->index;
+      png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)1);
+   }
+   else if (color_type & PNG_COLOR_MASK_COLOR)
+   {
+      png_save_uint_16(buf, back->red);
+      png_save_uint_16(buf + 2, back->green);
+      png_save_uint_16(buf + 4, back->blue);
+      if(png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]))
+         {
+            png_warning(png_ptr,
+              "Ignoring attempt to write 16-bit bKGD chunk when bit_depth is 8");
+            return;
+         }
+      png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)6);
+   }
+   else
+   {
+      if(back->gray >= (1 << png_ptr->bit_depth))
+      {
+         png_warning(png_ptr,
+           "Ignoring attempt to write bKGD chunk out-of-range for bit_depth");
+         return;
+      }
+      png_save_uint_16(buf, back->gray);
+      png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)2);
+   }
+}
+#endif
+
+#if defined(PNG_WRITE_hIST_SUPPORTED)
+/* write the histogram */
+void /* PRIVATE */
+png_write_hIST(png_structp png_ptr, png_uint_16p hist, int num_hist)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_hIST;
+#endif
+   int i;
+   png_byte buf[3];
+
+   png_debug(1, "in png_write_hIST\n");
+   if (num_hist > (int)png_ptr->num_palette)
+   {
+      png_debug2(3, "num_hist = %d, num_palette = %d\n", num_hist,
+         png_ptr->num_palette);
+      png_warning(png_ptr, "Invalid number of histogram entries specified");
+      return;
+   }
+
+   png_write_chunk_start(png_ptr, (png_bytep)png_hIST, (png_uint_32)(num_hist * 2));
+   for (i = 0; i < num_hist; i++)
+   {
+      png_save_uint_16(buf, hist[i]);
+      png_write_chunk_data(png_ptr, buf, (png_size_t)2);
+   }
+   png_write_chunk_end(png_ptr);
+}
+#endif
+
+#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
+    defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
+/* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification,
+ * and if invalid, correct the keyword rather than discarding the entire
+ * chunk.  The PNG 1.0 specification requires keywords 1-79 characters in
+ * length, forbids leading or trailing whitespace, multiple internal spaces,
+ * and the non-break space (0x80) from ISO 8859-1.  Returns keyword length.
+ *
+ * The new_key is allocated to hold the corrected keyword and must be freed
+ * by the calling routine.  This avoids problems with trying to write to
+ * static keywords without having to have duplicate copies of the strings.
+ */
+png_size_t /* PRIVATE */
+png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key)
+{
+   png_size_t key_len;
+   png_charp kp, dp;
+   int kflag;
+   int kwarn=0;
+
+   png_debug(1, "in png_check_keyword\n");
+   *new_key = NULL;
+
+   if (key == NULL || (key_len = png_strlen(key)) == 0)
+   {
+      png_warning(png_ptr, "zero length keyword");
+      return ((png_size_t)0);
+   }
+
+   png_debug1(2, "Keyword to be checked is '%s'\n", key);
+
+   *new_key = (png_charp)png_malloc_warn(png_ptr, (png_uint_32)(key_len + 2));
+   if (*new_key == NULL)
+   {
+      png_warning(png_ptr, "Out of memory while procesing keyword");
+      return ((png_size_t)0);
+   }
+
+   /* Replace non-printing characters with a blank and print a warning */
+   for (kp = key, dp = *new_key; *kp != '\0'; kp++, dp++)
+   {
+      if (*kp < 0x20 || (*kp > 0x7E && (png_byte)*kp < 0xA1))
+      {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+         char msg[40];
+
+         sprintf(msg, "invalid keyword character 0x%02X", *kp);
+         png_warning(png_ptr, msg);
+#else
+         png_warning(png_ptr, "invalid character in keyword");
+#endif
+         *dp = ' ';
+      }
+      else
+      {
+         *dp = *kp;
+      }
+   }
+   *dp = '\0';
+
+   /* Remove any trailing white space. */
+   kp = *new_key + key_len - 1;
+   if (*kp == ' ')
+   {
+      png_warning(png_ptr, "trailing spaces removed from keyword");
+
+      while (*kp == ' ')
+      {
+        *(kp--) = '\0';
+        key_len--;
+      }
+   }
+
+   /* Remove any leading white space. */
+   kp = *new_key;
+   if (*kp == ' ')
+   {
+      png_warning(png_ptr, "leading spaces removed from keyword");
+
+      while (*kp == ' ')
+      {
+        kp++;
+        key_len--;
+      }
+   }
+
+   png_debug1(2, "Checking for multiple internal spaces in '%s'\n", kp);
+
+   /* Remove multiple internal spaces. */
+   for (kflag = 0, dp = *new_key; *kp != '\0'; kp++)
+   {
+      if (*kp == ' ' && kflag == 0)
+      {
+         *(dp++) = *kp;
+         kflag = 1;
+      }
+      else if (*kp == ' ')
+      {
+         key_len--;
+         kwarn=1;
+      }
+      else
+      {
+         *(dp++) = *kp;
+         kflag = 0;
+      }
+   }
+   *dp = '\0';
+   if(kwarn)
+      png_warning(png_ptr, "extra interior spaces removed from keyword");
+
+   if (key_len == 0)
+   {
+      png_free(png_ptr, *new_key);
+      *new_key=NULL;
+      png_warning(png_ptr, "Zero length keyword");
+   }
+
+   if (key_len > 79)
+   {
+      png_warning(png_ptr, "keyword length must be 1 - 79 characters");
+      new_key[79] = '\0';
+      key_len = 79;
+   }
+
+   return (key_len);
+}
+#endif
+
+#if defined(PNG_WRITE_tEXt_SUPPORTED)
+/* write a tEXt chunk */
+void /* PRIVATE */
+png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text,
+   png_size_t text_len)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_tEXt;
+#endif
+   png_size_t key_len;
+   png_charp new_key;
+
+   png_debug(1, "in png_write_tEXt\n");
+   if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
+   {
+      png_warning(png_ptr, "Empty keyword in tEXt chunk");
+      return;
+   }
+
+   if (text == NULL || *text == '\0')
+      text_len = 0;
+   else
+      text_len = png_strlen(text);
+
+   /* make sure we include the 0 after the key */
+   png_write_chunk_start(png_ptr, (png_bytep)png_tEXt, (png_uint_32)key_len+text_len+1);
+   /*
+    * We leave it to the application to meet PNG-1.0 requirements on the
+    * contents of the text.  PNG-1.0 through PNG-1.2 discourage the use of
+    * any non-Latin-1 characters except for NEWLINE.  ISO PNG will forbid them.
+    * The NUL character is forbidden by PNG-1.0 through PNG-1.2 and ISO PNG.
+    */
+   png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1);
+   if (text_len)
+      png_write_chunk_data(png_ptr, (png_bytep)text, text_len);
+
+   png_write_chunk_end(png_ptr);
+   png_free(png_ptr, new_key);
+}
+#endif
+
+#if defined(PNG_WRITE_zTXt_SUPPORTED)
+/* write a compressed text chunk */
+void /* PRIVATE */
+png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
+   png_size_t text_len, int compression)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_zTXt;
+#endif
+   png_size_t key_len;
+   char buf[1];
+   png_charp new_key;
+   compression_state comp;
+
+   png_debug(1, "in png_write_zTXt\n");
+
+   if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
+   {
+      png_warning(png_ptr, "Empty keyword in zTXt chunk");
+      return;
+   }
+
+   if (text == NULL || *text == '\0' || compression==PNG_TEXT_COMPRESSION_NONE)
+   {
+      png_write_tEXt(png_ptr, new_key, text, (png_size_t)0);
+      png_free(png_ptr, new_key);
+      return;
+   }
+
+   text_len = png_strlen(text);
+
+   png_free(png_ptr, new_key);
+
+   /* compute the compressed data; do it now for the length */
+   text_len = png_text_compress(png_ptr, text, text_len, compression,
+       &comp);
+
+   /* write start of chunk */
+   png_write_chunk_start(png_ptr, (png_bytep)png_zTXt, (png_uint_32)
+      (key_len+text_len+2));
+   /* write key */
+   png_write_chunk_data(png_ptr, (png_bytep)key, key_len + 1);
+   buf[0] = (png_byte)compression;
+   /* write compression */
+   png_write_chunk_data(png_ptr, (png_bytep)buf, (png_size_t)1);
+   /* write the compressed data */
+   png_write_compressed_data_out(png_ptr, &comp);
+
+   /* close the chunk */
+   png_write_chunk_end(png_ptr);
+}
+#endif
+
+#if defined(PNG_WRITE_iTXt_SUPPORTED)
+/* write an iTXt chunk */
+void /* PRIVATE */
+png_write_iTXt(png_structp png_ptr, int compression, png_charp key,
+    png_charp lang, png_charp lang_key, png_charp text)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_iTXt;
+#endif
+   png_size_t lang_len, key_len, lang_key_len, text_len;
+   png_charp new_lang, new_key;
+   png_byte cbuf[2];
+   compression_state comp;
+
+   png_debug(1, "in png_write_iTXt\n");
+
+   if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
+   {
+      png_warning(png_ptr, "Empty keyword in iTXt chunk");
+      return;
+   }
+   if (lang == NULL || (lang_len = png_check_keyword(png_ptr, lang, &new_lang))==0)
+   {
+      png_warning(png_ptr, "Empty language field in iTXt chunk");
+      new_lang = NULL;
+      lang_len = 0;
+   }
+
+   if (lang_key == NULL)
+     lang_key_len = 0;
+   else
+     lang_key_len = png_strlen(lang_key);
+
+   if (text == NULL)
+      text_len = 0;
+   else
+     text_len = png_strlen(text);
+
+   /* compute the compressed data; do it now for the length */
+   text_len = png_text_compress(png_ptr, text, text_len, compression-2,
+      &comp);
+
+
+   /* make sure we include the compression flag, the compression byte,
+    * and the NULs after the key, lang, and lang_key parts */
+
+   png_write_chunk_start(png_ptr, (png_bytep)png_iTXt,
+          (png_uint_32)(
+        5 /* comp byte, comp flag, terminators for key, lang and lang_key */
+        + key_len
+        + lang_len
+        + lang_key_len
+        + text_len));
+
+   /*
+    * We leave it to the application to meet PNG-1.0 requirements on the
+    * contents of the text.  PNG-1.0 through PNG-1.2 discourage the use of
+    * any non-Latin-1 characters except for NEWLINE.  ISO PNG will forbid them.
+    * The NUL character is forbidden by PNG-1.0 through PNG-1.2 and ISO PNG.
+    */
+   png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1);
+
+   /* set the compression flag */
+   if (compression == PNG_ITXT_COMPRESSION_NONE || \
+       compression == PNG_TEXT_COMPRESSION_NONE)
+       cbuf[0] = 0;
+   else /* compression == PNG_ITXT_COMPRESSION_zTXt */
+       cbuf[0] = 1;
+   /* set the compression method */
+   cbuf[1] = 0;
+   png_write_chunk_data(png_ptr, cbuf, 2);
+
+   cbuf[0] = 0;
+   png_write_chunk_data(png_ptr, (new_lang ? (png_bytep)new_lang : cbuf), lang_len + 1);
+   png_write_chunk_data(png_ptr, (lang_key ? (png_bytep)lang_key : cbuf), lang_key_len + 1);
+   png_write_compressed_data_out(png_ptr, &comp);
+
+   png_write_chunk_end(png_ptr);
+   png_free(png_ptr, new_key);
+   if (new_lang)
+     png_free(png_ptr, new_lang);
+}
+#endif
+
+#if defined(PNG_WRITE_oFFs_SUPPORTED)
+/* write the oFFs chunk */
+void /* PRIVATE */
+png_write_oFFs(png_structp png_ptr, png_int_32 x_offset, png_int_32 y_offset,
+   int unit_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_oFFs;
+#endif
+   png_byte buf[9];
+
+   png_debug(1, "in png_write_oFFs\n");
+   if (unit_type >= PNG_OFFSET_LAST)
+      png_warning(png_ptr, "Unrecognized unit type for oFFs chunk");
+
+   png_save_int_32(buf, x_offset);
+   png_save_int_32(buf + 4, y_offset);
+   buf[8] = (png_byte)unit_type;
+
+   png_write_chunk(png_ptr, (png_bytep)png_oFFs, buf, (png_size_t)9);
+}
+#endif
+
+#if defined(PNG_WRITE_pCAL_SUPPORTED)
+/* write the pCAL chunk (described in the PNG extensions document) */
+void /* PRIVATE */
+png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
+   png_int_32 X1, int type, int nparams, png_charp units, png_charpp params)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_pCAL;
+#endif
+   png_size_t purpose_len, units_len, total_len;
+   png_uint_32p params_len;
+   png_byte buf[10];
+   png_charp new_purpose;
+   int i;
+
+   png_debug1(1, "in png_write_pCAL (%d parameters)\n", nparams);
+   if (type >= PNG_EQUATION_LAST)
+      png_warning(png_ptr, "Unrecognized equation type for pCAL chunk");
+
+   purpose_len = png_check_keyword(png_ptr, purpose, &new_purpose) + 1;
+   png_debug1(3, "pCAL purpose length = %d\n", (int)purpose_len);
+   units_len = png_strlen(units) + (nparams == 0 ? 0 : 1);
+   png_debug1(3, "pCAL units length = %d\n", (int)units_len);
+   total_len = purpose_len + units_len + 10;
+
+   params_len = (png_uint_32p)png_malloc(png_ptr, (png_uint_32)(nparams
+      *png_sizeof(png_uint_32)));
+
+   /* Find the length of each parameter, making sure we don't count the
+      null terminator for the last parameter. */
+   for (i = 0; i < nparams; i++)
+   {
+      params_len[i] = png_strlen(params[i]) + (i == nparams - 1 ? 0 : 1);
+      png_debug2(3, "pCAL parameter %d length = %lu\n", i, params_len[i]);
+      total_len += (png_size_t)params_len[i];
+   }
+
+   png_debug1(3, "pCAL total length = %d\n", (int)total_len);
+   png_write_chunk_start(png_ptr, (png_bytep)png_pCAL, (png_uint_32)total_len);
+   png_write_chunk_data(png_ptr, (png_bytep)new_purpose, purpose_len);
+   png_save_int_32(buf, X0);
+   png_save_int_32(buf + 4, X1);
+   buf[8] = (png_byte)type;
+   buf[9] = (png_byte)nparams;
+   png_write_chunk_data(png_ptr, buf, (png_size_t)10);
+   png_write_chunk_data(png_ptr, (png_bytep)units, (png_size_t)units_len);
+
+   png_free(png_ptr, new_purpose);
+
+   for (i = 0; i < nparams; i++)
+   {
+      png_write_chunk_data(png_ptr, (png_bytep)params[i],
+         (png_size_t)params_len[i]);
+   }
+
+   png_free(png_ptr, params_len);
+   png_write_chunk_end(png_ptr);
+}
+#endif
+
+#if defined(PNG_WRITE_sCAL_SUPPORTED)
+/* write the sCAL chunk */
+#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
+void /* PRIVATE */
+png_write_sCAL(png_structp png_ptr, int unit, double width,double height)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_sCAL;
+#endif
+   png_size_t total_len;
+   char wbuf[32], hbuf[32];
+   png_byte bunit = unit;
+
+   png_debug(1, "in png_write_sCAL\n");
+
+#if defined(_WIN32_WCE)
+/* sprintf() function is not supported on WindowsCE */
+   {
+      wchar_t wc_buf[32];
+      swprintf(wc_buf, TEXT("%12.12e"), width);
+      WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, wbuf, 32, NULL, NULL);
+      swprintf(wc_buf, TEXT("%12.12e"), height);
+      WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, hbuf, 32, NULL, NULL);
+   }
+#else
+   sprintf(wbuf, "%12.12e", width);
+   sprintf(hbuf, "%12.12e", height);
+#endif
+   total_len = 1 + png_strlen(wbuf)+1 + png_strlen(hbuf);
+
+   png_debug1(3, "sCAL total length = %d\n", (int)total_len);
+   png_write_chunk_start(png_ptr, (png_bytep)png_sCAL, (png_uint_32)total_len);
+   png_write_chunk_data(png_ptr, (png_bytep)&bunit, 1);
+   png_write_chunk_data(png_ptr, (png_bytep)wbuf, png_strlen(wbuf)+1);
+   png_write_chunk_data(png_ptr, (png_bytep)hbuf, png_strlen(hbuf));
+
+   png_write_chunk_end(png_ptr);
+}
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void /* PRIVATE */
+png_write_sCAL_s(png_structp png_ptr, int unit, png_charp width,
+   png_charp height)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_sCAL;
+#endif
+   png_size_t total_len;
+   char wbuf[32], hbuf[32];
+   png_byte bunit = unit;
+
+   png_debug(1, "in png_write_sCAL_s\n");
+
+   png_strcpy(wbuf,(const char *)width);
+   png_strcpy(hbuf,(const char *)height);
+   total_len = 1 + png_strlen(wbuf)+1 + png_strlen(hbuf);
+
+   png_debug1(3, "sCAL total length = %d\n", total_len);
+   png_write_chunk_start(png_ptr, (png_bytep)png_sCAL, (png_uint_32)total_len);
+   png_write_chunk_data(png_ptr, (png_bytep)&bunit, 1);
+   png_write_chunk_data(png_ptr, (png_bytep)wbuf, png_strlen(wbuf)+1);
+   png_write_chunk_data(png_ptr, (png_bytep)hbuf, png_strlen(hbuf));
+
+   png_write_chunk_end(png_ptr);
+}
+#endif
+#endif
+#endif
+
+#if defined(PNG_WRITE_pHYs_SUPPORTED)
+/* write the pHYs chunk */
+void /* PRIVATE */
+png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit,
+   png_uint_32 y_pixels_per_unit,
+   int unit_type)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_pHYs;
+#endif
+   png_byte buf[9];
+
+   png_debug(1, "in png_write_pHYs\n");
+   if (unit_type >= PNG_RESOLUTION_LAST)
+      png_warning(png_ptr, "Unrecognized unit type for pHYs chunk");
+
+   png_save_uint_32(buf, x_pixels_per_unit);
+   png_save_uint_32(buf + 4, y_pixels_per_unit);
+   buf[8] = (png_byte)unit_type;
+
+   png_write_chunk(png_ptr, (png_bytep)png_pHYs, buf, (png_size_t)9);
+}
+#endif
+
+#if defined(PNG_WRITE_tIME_SUPPORTED)
+/* Write the tIME chunk.  Use either png_convert_from_struct_tm()
+ * or png_convert_from_time_t(), or fill in the structure yourself.
+ */
+void /* PRIVATE */
+png_write_tIME(png_structp png_ptr, png_timep mod_time)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_tIME;
+#endif
+   png_byte buf[7];
+
+   png_debug(1, "in png_write_tIME\n");
+   if (mod_time->month  > 12 || mod_time->month  < 1 ||
+       mod_time->day    > 31 || mod_time->day    < 1 ||
+       mod_time->hour   > 23 || mod_time->second > 60)
+   {
+      png_warning(png_ptr, "Invalid time specified for tIME chunk");
+      return;
+   }
+
+   png_save_uint_16(buf, mod_time->year);
+   buf[2] = mod_time->month;
+   buf[3] = mod_time->day;
+   buf[4] = mod_time->hour;
+   buf[5] = mod_time->minute;
+   buf[6] = mod_time->second;
+
+   png_write_chunk(png_ptr, (png_bytep)png_tIME, buf, (png_size_t)7);
+}
+#endif
+
+/* initializes the row writing capability of libpng */
+void /* PRIVATE */
+png_write_start_row(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+   /* start of interlace block */
+   int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+
+   /* offset to next interlace block */
+   int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+
+   /* start of interlace block in the y direction */
+   int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+
+   /* offset to next interlace block in the y direction */
+   int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+
+   png_size_t buf_size;
+
+   png_debug(1, "in png_write_start_row\n");
+   buf_size = (png_size_t)(PNG_ROWBYTES(
+      png_ptr->usr_channels*png_ptr->usr_bit_depth,png_ptr->width)+1);
+
+   /* set up row buffer */
+   png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size);
+   png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE;
+
+   /* set up filtering buffer, if using this filter */
+   if (png_ptr->do_filter & PNG_FILTER_SUB)
+   {
+      png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
+         (png_ptr->rowbytes + 1));
+      png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
+   }
+
+   /* We only need to keep the previous row if we are using one of these. */
+   if (png_ptr->do_filter & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH))
+   {
+     /* set up previous row buffer */
+      png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size);
+      png_memset(png_ptr->prev_row, 0, buf_size);
+
+      if (png_ptr->do_filter & PNG_FILTER_UP)
+      {
+         png_ptr->up_row = (png_bytep )png_malloc(png_ptr,
+            (png_ptr->rowbytes + 1));
+         png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
+      }
+
+      if (png_ptr->do_filter & PNG_FILTER_AVG)
+      {
+         png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
+            (png_ptr->rowbytes + 1));
+         png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
+      }
+
+      if (png_ptr->do_filter & PNG_FILTER_PAETH)
+      {
+         png_ptr->paeth_row = (png_bytep )png_malloc(png_ptr,
+            (png_ptr->rowbytes + 1));
+         png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
+      }
+   }
+
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+   /* if interlaced, we need to set up width and height of pass */
+   if (png_ptr->interlaced)
+   {
+      if (!(png_ptr->transformations & PNG_INTERLACE))
+      {
+         png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
+            png_pass_ystart[0]) / png_pass_yinc[0];
+         png_ptr->usr_width = (png_ptr->width + png_pass_inc[0] - 1 -
+            png_pass_start[0]) / png_pass_inc[0];
+      }
+      else
+      {
+         png_ptr->num_rows = png_ptr->height;
+         png_ptr->usr_width = png_ptr->width;
+      }
+   }
+   else
+#endif
+   {
+      png_ptr->num_rows = png_ptr->height;
+      png_ptr->usr_width = png_ptr->width;
+   }
+   png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+   png_ptr->zstream.next_out = png_ptr->zbuf;
+}
+
+/* Internal use only.  Called when finished processing a row of data. */
+void /* PRIVATE */
+png_write_finish_row(png_structp png_ptr)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+   /* start of interlace block */
+   int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+
+   /* offset to next interlace block */
+   int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+
+   /* start of interlace block in the y direction */
+   int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+
+   /* offset to next interlace block in the y direction */
+   int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+
+   int ret;
+
+   png_debug(1, "in png_write_finish_row\n");
+   /* next row */
+   png_ptr->row_number++;
+
+   /* see if we are done */
+   if (png_ptr->row_number < png_ptr->num_rows)
+      return;
+
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+   /* if interlaced, go to next pass */
+   if (png_ptr->interlaced)
+   {
+      png_ptr->row_number = 0;
+      if (png_ptr->transformations & PNG_INTERLACE)
+      {
+         png_ptr->pass++;
+      }
+      else
+      {
+         /* loop until we find a non-zero width or height pass */
+         do
+         {
+            png_ptr->pass++;
+            if (png_ptr->pass >= 7)
+               break;
+            png_ptr->usr_width = (png_ptr->width +
+               png_pass_inc[png_ptr->pass] - 1 -
+               png_pass_start[png_ptr->pass]) /
+               png_pass_inc[png_ptr->pass];
+            png_ptr->num_rows = (png_ptr->height +
+               png_pass_yinc[png_ptr->pass] - 1 -
+               png_pass_ystart[png_ptr->pass]) /
+               png_pass_yinc[png_ptr->pass];
+            if (png_ptr->transformations & PNG_INTERLACE)
+               break;
+         } while (png_ptr->usr_width == 0 || png_ptr->num_rows == 0);
+
+      }
+
+      /* reset the row above the image for the next pass */
+      if (png_ptr->pass < 7)
+      {
+         if (png_ptr->prev_row != NULL)
+            png_memset(png_ptr->prev_row, 0,
+               (png_size_t)(PNG_ROWBYTES(png_ptr->usr_channels*
+               png_ptr->usr_bit_depth,png_ptr->width))+1);
+         return;
+      }
+   }
+#endif
+
+   /* if we get here, we've just written the last row, so we need
+      to flush the compressor */
+   do
+   {
+      /* tell the compressor we are done */
+      ret = deflate(&png_ptr->zstream, Z_FINISH);
+      /* check for an error */
+      if (ret == Z_OK)
+      {
+         /* check to see if we need more room */
+         if (!(png_ptr->zstream.avail_out))
+         {
+            png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
+            png_ptr->zstream.next_out = png_ptr->zbuf;
+            png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+         }
+      }
+      else if (ret != Z_STREAM_END)
+      {
+         if (png_ptr->zstream.msg != NULL)
+            png_error(png_ptr, png_ptr->zstream.msg);
+         else
+            png_error(png_ptr, "zlib error");
+      }
+   } while (ret != Z_STREAM_END);
+
+   /* write any extra space */
+   if (png_ptr->zstream.avail_out < png_ptr->zbuf_size)
+   {
+      png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size -
+         png_ptr->zstream.avail_out);
+   }
+
+   deflateReset(&png_ptr->zstream);
+   png_ptr->zstream.data_type = Z_BINARY;
+}
+
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+/* Pick out the correct pixels for the interlace pass.
+ * The basic idea here is to go through the row with a source
+ * pointer and a destination pointer (sp and dp), and copy the
+ * correct pixels for the pass.  As the row gets compacted,
+ * sp will always be >= dp, so we should never overwrite anything.
+ * See the default: case for the easiest code to understand.
+ */
+void /* PRIVATE */
+png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+   /* start of interlace block */
+   int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+
+   /* offset to next interlace block */
+   int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+#endif
+
+   png_debug(1, "in png_do_write_interlace\n");
+   /* we don't have to do anything on the last pass (6) */
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL && pass < 6)
+#else
+   if (pass < 6)
+#endif
+   {
+      /* each pixel depth is handled separately */
+      switch (row_info->pixel_depth)
+      {
+         case 1:
+         {
+            png_bytep sp;
+            png_bytep dp;
+            int shift;
+            int d;
+            int value;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            dp = row;
+            d = 0;
+            shift = 7;
+            for (i = png_pass_start[pass]; i < row_width;
+               i += png_pass_inc[pass])
+            {
+               sp = row + (png_size_t)(i >> 3);
+               value = (int)(*sp >> (7 - (int)(i & 0x07))) & 0x01;
+               d |= (value << shift);
+
+               if (shift == 0)
+               {
+                  shift = 7;
+                  *dp++ = (png_byte)d;
+                  d = 0;
+               }
+               else
+                  shift--;
+
+            }
+            if (shift != 7)
+               *dp = (png_byte)d;
+            break;
+         }
+         case 2:
+         {
+            png_bytep sp;
+            png_bytep dp;
+            int shift;
+            int d;
+            int value;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            dp = row;
+            shift = 6;
+            d = 0;
+            for (i = png_pass_start[pass]; i < row_width;
+               i += png_pass_inc[pass])
+            {
+               sp = row + (png_size_t)(i >> 2);
+               value = (*sp >> ((3 - (int)(i & 0x03)) << 1)) & 0x03;
+               d |= (value << shift);
+
+               if (shift == 0)
+               {
+                  shift = 6;
+                  *dp++ = (png_byte)d;
+                  d = 0;
+               }
+               else
+                  shift -= 2;
+            }
+            if (shift != 6)
+                   *dp = (png_byte)d;
+            break;
+         }
+         case 4:
+         {
+            png_bytep sp;
+            png_bytep dp;
+            int shift;
+            int d;
+            int value;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            dp = row;
+            shift = 4;
+            d = 0;
+            for (i = png_pass_start[pass]; i < row_width;
+               i += png_pass_inc[pass])
+            {
+               sp = row + (png_size_t)(i >> 1);
+               value = (*sp >> ((1 - (int)(i & 0x01)) << 2)) & 0x0f;
+               d |= (value << shift);
+
+               if (shift == 0)
+               {
+                  shift = 4;
+                  *dp++ = (png_byte)d;
+                  d = 0;
+               }
+               else
+                  shift -= 4;
+            }
+            if (shift != 4)
+               *dp = (png_byte)d;
+            break;
+         }
+         default:
+         {
+            png_bytep sp;
+            png_bytep dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+            png_size_t pixel_bytes;
+
+            /* start at the beginning */
+            dp = row;
+            /* find out how many bytes each pixel takes up */
+            pixel_bytes = (row_info->pixel_depth >> 3);
+            /* loop through the row, only looking at the pixels that
+               matter */
+            for (i = png_pass_start[pass]; i < row_width;
+               i += png_pass_inc[pass])
+            {
+               /* find out where the original pixel is */
+               sp = row + (png_size_t)i * pixel_bytes;
+               /* move the pixel */
+               if (dp != sp)
+                  png_memcpy(dp, sp, pixel_bytes);
+               /* next pixel */
+               dp += pixel_bytes;
+            }
+            break;
+         }
+      }
+      /* set new row width */
+      row_info->width = (row_info->width +
+         png_pass_inc[pass] - 1 -
+         png_pass_start[pass]) /
+         png_pass_inc[pass];
+         row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,
+            row_info->width);
+   }
+}
+#endif
+
+/* This filters the row, chooses which filter to use, if it has not already
+ * been specified by the application, and then writes the row out with the
+ * chosen filter.
+ */
+#define PNG_MAXSUM (((png_uint_32)(-1)) >> 1)
+#define PNG_HISHIFT 10
+#define PNG_LOMASK ((png_uint_32)0xffffL)
+#define PNG_HIMASK ((png_uint_32)(~PNG_LOMASK >> PNG_HISHIFT))
+void /* PRIVATE */
+png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
+{
+   png_bytep prev_row, best_row, row_buf;
+   png_uint_32 mins, bpp;
+   png_byte filter_to_do = png_ptr->do_filter;
+   png_uint_32 row_bytes = row_info->rowbytes;
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+   int num_p_filters = (int)png_ptr->num_prev_filters;
+#endif
+
+   png_debug(1, "in png_write_find_filter\n");
+   /* find out how many bytes offset each pixel is */
+   bpp = (row_info->pixel_depth + 7) >> 3;
+
+   prev_row = png_ptr->prev_row;
+   best_row = row_buf = png_ptr->row_buf;
+   mins = PNG_MAXSUM;
+
+   /* The prediction method we use is to find which method provides the
+    * smallest value when summing the absolute values of the distances
+    * from zero, using anything >= 128 as negative numbers.  This is known
+    * as the "minimum sum of absolute differences" heuristic.  Other
+    * heuristics are the "weighted minimum sum of absolute differences"
+    * (experimental and can in theory improve compression), and the "zlib
+    * predictive" method (not implemented yet), which does test compressions
+    * of lines using different filter methods, and then chooses the
+    * (series of) filter(s) that give minimum compressed data size (VERY
+    * computationally expensive).
+    *
+    * GRR 980525:  consider also
+    *   (1) minimum sum of absolute differences from running average (i.e.,
+    *       keep running sum of non-absolute differences & count of bytes)
+    *       [track dispersion, too?  restart average if dispersion too large?]
+    *  (1b) minimum sum of absolute differences from sliding average, probably
+    *       with window size <= deflate window (usually 32K)
+    *   (2) minimum sum of squared differences from zero or running average
+    *       (i.e., ~ root-mean-square approach)
+    */
+
+
+   /* We don't need to test the 'no filter' case if this is the only filter
+    * that has been chosen, as it doesn't actually do anything to the data.
+    */
+   if ((filter_to_do & PNG_FILTER_NONE) &&
+       filter_to_do != PNG_FILTER_NONE)
+   {
+      png_bytep rp;
+      png_uint_32 sum = 0;
+      png_uint_32 i;
+      int v;
+
+      for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++)
+      {
+         v = *rp;
+         sum += (v < 128) ? v : 256 - v;
+      }
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+      {
+         png_uint_32 sumhi, sumlo;
+         int j;
+         sumlo = sum & PNG_LOMASK;
+         sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; /* Gives us some footroom */
+
+         /* Reduce the sum if we match any of the previous rows */
+         for (j = 0; j < num_p_filters; j++)
+         {
+            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE)
+            {
+               sumlo = (sumlo * png_ptr->filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+               sumhi = (sumhi * png_ptr->filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+            }
+         }
+
+         /* Factor in the cost of this filter (this is here for completeness,
+          * but it makes no sense to have a "cost" for the NONE filter, as
+          * it has the minimum possible computational cost - none).
+          */
+         sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >>
+            PNG_COST_SHIFT;
+         sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >>
+            PNG_COST_SHIFT;
+
+         if (sumhi > PNG_HIMASK)
+            sum = PNG_MAXSUM;
+         else
+            sum = (sumhi << PNG_HISHIFT) + sumlo;
+      }
+#endif
+      mins = sum;
+   }
+
+   /* sub filter */
+   if (filter_to_do == PNG_FILTER_SUB)
+   /* it's the only filter so no testing is needed */
+   {
+      png_bytep rp, lp, dp;
+      png_uint_32 i;
+      for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp;
+           i++, rp++, dp++)
+      {
+         *dp = *rp;
+      }
+      for (lp = row_buf + 1; i < row_bytes;
+         i++, rp++, lp++, dp++)
+      {
+         *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
+      }
+      best_row = png_ptr->sub_row;
+   }
+
+   else if (filter_to_do & PNG_FILTER_SUB)
+   {
+      png_bytep rp, dp, lp;
+      png_uint_32 sum = 0, lmins = mins;
+      png_uint_32 i;
+      int v;
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+      /* We temporarily increase the "minimum sum" by the factor we
+       * would reduce the sum of this filter, so that we can do the
+       * early exit comparison without scaling the sum each time.
+       */
+      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+      {
+         int j;
+         png_uint_32 lmhi, lmlo;
+         lmlo = lmins & PNG_LOMASK;
+         lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
+
+         for (j = 0; j < num_p_filters; j++)
+         {
+            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB)
+            {
+               lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+               lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+            }
+         }
+
+         lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
+            PNG_COST_SHIFT;
+         lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
+            PNG_COST_SHIFT;
+
+         if (lmhi > PNG_HIMASK)
+            lmins = PNG_MAXSUM;
+         else
+            lmins = (lmhi << PNG_HISHIFT) + lmlo;
+      }
+#endif
+
+      for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp;
+           i++, rp++, dp++)
+      {
+         v = *dp = *rp;
+
+         sum += (v < 128) ? v : 256 - v;
+      }
+      for (lp = row_buf + 1; i < row_bytes;
+         i++, rp++, lp++, dp++)
+      {
+         v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
+
+         sum += (v < 128) ? v : 256 - v;
+
+         if (sum > lmins)  /* We are already worse, don't continue. */
+            break;
+      }
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+      {
+         int j;
+         png_uint_32 sumhi, sumlo;
+         sumlo = sum & PNG_LOMASK;
+         sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
+
+         for (j = 0; j < num_p_filters; j++)
+         {
+            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB)
+            {
+               sumlo = (sumlo * png_ptr->inv_filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+               sumhi = (sumhi * png_ptr->inv_filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+            }
+         }
+
+         sumlo = (sumlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
+            PNG_COST_SHIFT;
+         sumhi = (sumhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
+            PNG_COST_SHIFT;
+
+         if (sumhi > PNG_HIMASK)
+            sum = PNG_MAXSUM;
+         else
+            sum = (sumhi << PNG_HISHIFT) + sumlo;
+      }
+#endif
+
+      if (sum < mins)
+      {
+         mins = sum;
+         best_row = png_ptr->sub_row;
+      }
+   }
+
+   /* up filter */
+   if (filter_to_do == PNG_FILTER_UP)
+   {
+      png_bytep rp, dp, pp;
+      png_uint_32 i;
+
+      for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1,
+           pp = prev_row + 1; i < row_bytes;
+           i++, rp++, pp++, dp++)
+      {
+         *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
+      }
+      best_row = png_ptr->up_row;
+   }
+
+   else if (filter_to_do & PNG_FILTER_UP)
+   {
+      png_bytep rp, dp, pp;
+      png_uint_32 sum = 0, lmins = mins;
+      png_uint_32 i;
+      int v;
+
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+      {
+         int j;
+         png_uint_32 lmhi, lmlo;
+         lmlo = lmins & PNG_LOMASK;
+         lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
+
+         for (j = 0; j < num_p_filters; j++)
+         {
+            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP)
+            {
+               lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+               lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+            }
+         }
+
+         lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >>
+            PNG_COST_SHIFT;
+         lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >>
+            PNG_COST_SHIFT;
+
+         if (lmhi > PNG_HIMASK)
+            lmins = PNG_MAXSUM;
+         else
+            lmins = (lmhi << PNG_HISHIFT) + lmlo;
+      }
+#endif
+
+      for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1,
+           pp = prev_row + 1; i < row_bytes; i++)
+      {
+         v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
+
+         sum += (v < 128) ? v : 256 - v;
+
+         if (sum > lmins)  /* We are already worse, don't continue. */
+            break;
+      }
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+      {
+         int j;
+         png_uint_32 sumhi, sumlo;
+         sumlo = sum & PNG_LOMASK;
+         sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
+
+         for (j = 0; j < num_p_filters; j++)
+         {
+            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP)
+            {
+               sumlo = (sumlo * png_ptr->filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+               sumhi = (sumhi * png_ptr->filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+            }
+         }
+
+         sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >>
+            PNG_COST_SHIFT;
+         sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >>
+            PNG_COST_SHIFT;
+
+         if (sumhi > PNG_HIMASK)
+            sum = PNG_MAXSUM;
+         else
+            sum = (sumhi << PNG_HISHIFT) + sumlo;
+      }
+#endif
+
+      if (sum < mins)
+      {
+         mins = sum;
+         best_row = png_ptr->up_row;
+      }
+   }
+
+   /* avg filter */
+   if (filter_to_do == PNG_FILTER_AVG)
+   {
+      png_bytep rp, dp, pp, lp;
+      png_uint_32 i;
+      for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1,
+           pp = prev_row + 1; i < bpp; i++)
+      {
+         *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff);
+      }
+      for (lp = row_buf + 1; i < row_bytes; i++)
+      {
+         *dp++ = (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2))
+                 & 0xff);
+      }
+      best_row = png_ptr->avg_row;
+   }
+
+   else if (filter_to_do & PNG_FILTER_AVG)
+   {
+      png_bytep rp, dp, pp, lp;
+      png_uint_32 sum = 0, lmins = mins;
+      png_uint_32 i;
+      int v;
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+      {
+         int j;
+         png_uint_32 lmhi, lmlo;
+         lmlo = lmins & PNG_LOMASK;
+         lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
+
+         for (j = 0; j < num_p_filters; j++)
+         {
+            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_AVG)
+            {
+               lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+               lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+            }
+         }
+
+         lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >>
+            PNG_COST_SHIFT;
+         lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >>
+            PNG_COST_SHIFT;
+
+         if (lmhi > PNG_HIMASK)
+            lmins = PNG_MAXSUM;
+         else
+            lmins = (lmhi << PNG_HISHIFT) + lmlo;
+      }
+#endif
+
+      for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1,
+           pp = prev_row + 1; i < bpp; i++)
+      {
+         v = *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff);
+
+         sum += (v < 128) ? v : 256 - v;
+      }
+      for (lp = row_buf + 1; i < row_bytes; i++)
+      {
+         v = *dp++ =
+          (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2)) & 0xff);
+
+         sum += (v < 128) ? v : 256 - v;
+
+         if (sum > lmins)  /* We are already worse, don't continue. */
+            break;
+      }
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+      {
+         int j;
+         png_uint_32 sumhi, sumlo;
+         sumlo = sum & PNG_LOMASK;
+         sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
+
+         for (j = 0; j < num_p_filters; j++)
+         {
+            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE)
+            {
+               sumlo = (sumlo * png_ptr->filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+               sumhi = (sumhi * png_ptr->filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+            }
+         }
+
+         sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >>
+            PNG_COST_SHIFT;
+         sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >>
+            PNG_COST_SHIFT;
+
+         if (sumhi > PNG_HIMASK)
+            sum = PNG_MAXSUM;
+         else
+            sum = (sumhi << PNG_HISHIFT) + sumlo;
+      }
+#endif
+
+      if (sum < mins)
+      {
+         mins = sum;
+         best_row = png_ptr->avg_row;
+      }
+   }
+
+   /* Paeth filter */
+   if (filter_to_do == PNG_FILTER_PAETH)
+   {
+      png_bytep rp, dp, pp, cp, lp;
+      png_uint_32 i;
+      for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1,
+           pp = prev_row + 1; i < bpp; i++)
+      {
+         *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
+      }
+
+      for (lp = row_buf + 1, cp = prev_row + 1; i < row_bytes; i++)
+      {
+         int a, b, c, pa, pb, pc, p;
+
+         b = *pp++;
+         c = *cp++;
+         a = *lp++;
+
+         p = b - c;
+         pc = a - c;
+
+#ifdef PNG_USE_ABS
+         pa = abs(p);
+         pb = abs(pc);
+         pc = abs(p + pc);
+#else
+         pa = p < 0 ? -p : p;
+         pb = pc < 0 ? -pc : pc;
+         pc = (p + pc) < 0 ? -(p + pc) : p + pc;
+#endif
+
+         p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
+
+         *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
+      }
+      best_row = png_ptr->paeth_row;
+   }
+
+   else if (filter_to_do & PNG_FILTER_PAETH)
+   {
+      png_bytep rp, dp, pp, cp, lp;
+      png_uint_32 sum = 0, lmins = mins;
+      png_uint_32 i;
+      int v;
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+      {
+         int j;
+         png_uint_32 lmhi, lmlo;
+         lmlo = lmins & PNG_LOMASK;
+         lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
+
+         for (j = 0; j < num_p_filters; j++)
+         {
+            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH)
+            {
+               lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+               lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+            }
+         }
+
+         lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >>
+            PNG_COST_SHIFT;
+         lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >>
+            PNG_COST_SHIFT;
+
+         if (lmhi > PNG_HIMASK)
+            lmins = PNG_MAXSUM;
+         else
+            lmins = (lmhi << PNG_HISHIFT) + lmlo;
+      }
+#endif
+
+      for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1,
+           pp = prev_row + 1; i < bpp; i++)
+      {
+         v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
+
+         sum += (v < 128) ? v : 256 - v;
+      }
+
+      for (lp = row_buf + 1, cp = prev_row + 1; i < row_bytes; i++)
+      {
+         int a, b, c, pa, pb, pc, p;
+
+         b = *pp++;
+         c = *cp++;
+         a = *lp++;
+
+#ifndef PNG_SLOW_PAETH
+         p = b - c;
+         pc = a - c;
+#ifdef PNG_USE_ABS
+         pa = abs(p);
+         pb = abs(pc);
+         pc = abs(p + pc);
+#else
+         pa = p < 0 ? -p : p;
+         pb = pc < 0 ? -pc : pc;
+         pc = (p + pc) < 0 ? -(p + pc) : p + pc;
+#endif
+         p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
+#else /* PNG_SLOW_PAETH */
+         p = a + b - c;
+         pa = abs(p - a);
+         pb = abs(p - b);
+         pc = abs(p - c);
+         if (pa <= pb && pa <= pc)
+            p = a;
+         else if (pb <= pc)
+            p = b;
+         else
+            p = c;
+#endif /* PNG_SLOW_PAETH */
+
+         v = *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
+
+         sum += (v < 128) ? v : 256 - v;
+
+         if (sum > lmins)  /* We are already worse, don't continue. */
+            break;
+      }
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+      {
+         int j;
+         png_uint_32 sumhi, sumlo;
+         sumlo = sum & PNG_LOMASK;
+         sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
+
+         for (j = 0; j < num_p_filters; j++)
+         {
+            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH)
+            {
+               sumlo = (sumlo * png_ptr->filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+               sumhi = (sumhi * png_ptr->filter_weights[j]) >>
+                  PNG_WEIGHT_SHIFT;
+            }
+         }
+
+         sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >>
+            PNG_COST_SHIFT;
+         sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >>
+            PNG_COST_SHIFT;
+
+         if (sumhi > PNG_HIMASK)
+            sum = PNG_MAXSUM;
+         else
+            sum = (sumhi << PNG_HISHIFT) + sumlo;
+      }
+#endif
+
+      if (sum < mins)
+      {
+         best_row = png_ptr->paeth_row;
+      }
+   }
+
+   /* Do the actual writing of the filtered row data from the chosen filter. */
+
+   png_write_filtered_row(png_ptr, best_row);
+
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
+   /* Save the type of filter we picked this time for future calculations */
+   if (png_ptr->num_prev_filters > 0)
+   {
+      int j;
+      for (j = 1; j < num_p_filters; j++)
+      {
+         png_ptr->prev_filters[j] = png_ptr->prev_filters[j - 1];
+      }
+      png_ptr->prev_filters[j] = best_row[0];
+   }
+#endif
+}
+
+
+/* Do the actual writing of a previously filtered row. */
+void /* PRIVATE */
+png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row)
+{
+   png_debug(1, "in png_write_filtered_row\n");
+   png_debug1(2, "filter = %d\n", filtered_row[0]);
+   /* set up the zlib input buffer */
+
+   png_ptr->zstream.next_in = filtered_row;
+   png_ptr->zstream.avail_in = (uInt)png_ptr->row_info.rowbytes + 1;
+   /* repeat until we have compressed all the data */
+   do
+   {
+      int ret; /* return of zlib */
+
+      /* compress the data */
+      ret = deflate(&png_ptr->zstream, Z_NO_FLUSH);
+      /* check for compression errors */
+      if (ret != Z_OK)
+      {
+         if (png_ptr->zstream.msg != NULL)
+            png_error(png_ptr, png_ptr->zstream.msg);
+         else
+            png_error(png_ptr, "zlib error");
+      }
+
+      /* see if it is time to write another IDAT */
+      if (!(png_ptr->zstream.avail_out))
+      {
+         /* write the IDAT and reset the zlib output buffer */
+         png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
+         png_ptr->zstream.next_out = png_ptr->zbuf;
+         png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+      }
+   /* repeat until all data has been compressed */
+   } while (png_ptr->zstream.avail_in);
+
+   /* swap the current and previous rows */
+   if (png_ptr->prev_row != NULL)
+   {
+      png_bytep tptr;
+
+      tptr = png_ptr->prev_row;
+      png_ptr->prev_row = png_ptr->row_buf;
+      png_ptr->row_buf = tptr;
+   }
+
+   /* finish row - updates counters and flushes zlib if last row */
+   png_write_finish_row(png_ptr);
+
+#if defined(PNG_WRITE_FLUSH_SUPPORTED)
+   png_ptr->flush_rows++;
+
+   if (png_ptr->flush_dist > 0 &&
+       png_ptr->flush_rows >= png_ptr->flush_dist)
+   {
+      png_write_flush(png_ptr);
+   }
+#endif
+}
+#endif /* PNG_WRITE_SUPPORTED */
diff --git a/gs/libpng/projects/beos/x86-shared.proj b/gs/libpng/projects/beos/x86-shared.proj
new file mode 100644
index 000000000..6d2e3c319
--- /dev/null
+++ b/gs/libpng/projects/beos/x86-shared.proj
diff --git a/gs/libpng/projects/beos/x86-shared.txt b/gs/libpng/projects/beos/x86-shared.txt
new file mode 100644
index 000000000..0cd4d9db4
--- /dev/null
+++ b/gs/libpng/projects/beos/x86-shared.txt
@@ -0,0 +1,22 @@
+This project builds a shared library version of libpng on x86 BeOS.
+
+It defines PNG_USE_PNGGCCRD, which activates the assembly code in
+pnggccrd.c; this hasn't been extensively tested on BeOS.
+
+To install:
+
+1) build
+
+   Note: As of version 1.0.10, you'll get a fair number of warnings when
+         you compile pnggccrd.c.  As far as I know, these are harmless,
+         but it would be better if someone fixed them.
+
+2) copy and png.h, pngconf.h somewhere; /boot/home/config/include (which
+   you'll have to make) is a good choice
+
+3) copy libpng.so to /boot/home/config/lib
+
+4) build your libpng.so applications (remember to include libz.a as
+   well when you link)
+
+- Chris Herborth, March 27, 2001
diff --git a/gs/libpng/projects/beos/x86-static.proj b/gs/libpng/projects/beos/x86-static.proj
new file mode 100644
index 000000000..37c075366
--- /dev/null
+++ b/gs/libpng/projects/beos/x86-static.proj
diff --git a/gs/libpng/projects/beos/x86-static.txt b/gs/libpng/projects/beos/x86-static.txt
new file mode 100644
index 000000000..bb80aaa5f
--- /dev/null
+++ b/gs/libpng/projects/beos/x86-static.txt
@@ -0,0 +1,22 @@
+This project builds a static library version of libpng on x86 BeOS.
+
+It defines PNG_USE_PNGGCCRD, which activates the assembly code in
+pnggccrd.c; this hasn't been extensively tested on BeOS.
+
+To install:
+
+1) build
+
+   Note: As of version 1.0.10, you'll get a fair number of warnings when
+         you compile pnggccrd.c.  As far as I know, these are harmless,
+         but it would be better if someone fixed them.
+
+2) copy and png.h, pngconf.h somewhere; /boot/home/config/include (which
+   you'll have to make) is a good choice
+
+3) copy libpng.a to /boot/home/config/lib
+
+4) build your libpng.a applications (remember to include libz.a as
+   well when you link)
+
+- Chris Herborth, March 27, 2001
diff --git a/gs/libpng/projects/cbuilder5/libpng.bpf b/gs/libpng/projects/cbuilder5/libpng.bpf
new file mode 100644
index 000000000..2af81e77c
--- /dev/null
+++ b/gs/libpng/projects/cbuilder5/libpng.bpf
@@ -0,0 +1,22 @@
+USEUNIT("libpng.cpp");
+USEUNIT("..\..\png.c");
+USEUNIT("..\..\pngerror.c");
+USEUNIT("..\..\pngget.c");
+USEUNIT("..\..\pngmem.c");
+USEUNIT("..\..\pngpread.c");
+USEUNIT("..\..\pngread.c");
+USEUNIT("..\..\pngrio.c");
+USEUNIT("..\..\pngrtran.c");
+USEUNIT("..\..\pngrutil.c");
+USEUNIT("..\..\pngset.c");
+USEUNIT("..\..\pngtrans.c");
+USEUNIT("..\..\pngwio.c");
+USEUNIT("..\..\pngwrite.c");
+USEUNIT("..\..\pngwtran.c");
+USEUNIT("..\..\pngwutil.c");
+USELIB("..\..\..\zlib\zlib.lib");
+//---------------------------------------------------------------------------
+This file is used by the project manager only and should be treated like the project file
+
+
+DllEntryPoint
diff --git a/gs/libpng/projects/cbuilder5/libpng.bpg b/gs/libpng/projects/cbuilder5/libpng.bpg
new file mode 100644
index 000000000..80c197719
--- /dev/null
+++ b/gs/libpng/projects/cbuilder5/libpng.bpg
@@ -0,0 +1,25 @@
+#------------------------------------------------------------------------------
+VERSION = BWS.01
+#------------------------------------------------------------------------------
+!ifndef ROOT
+ROOT = $(MAKEDIR)\..
+!endif
+#------------------------------------------------------------------------------
+MAKE = $(ROOT)\bin\make.exe -$(MAKEFLAGS) -f$**
+DCC = $(ROOT)\bin\dcc32.exe $**
+BRCC = $(ROOT)\bin\brcc32.exe $**
+#------------------------------------------------------------------------------
+PROJECTS = libpngstat.lib libpng.dll
+#------------------------------------------------------------------------------
+default: $(PROJECTS)
+#------------------------------------------------------------------------------
+
+libpngstat.lib: libpngstat.bpr
+  $(ROOT)\bin\bpr2mak -t$(ROOT)\bin\deflib.bmk $**
+  $(ROOT)\bin\make -$(MAKEFLAGS) -f$*.mak
+
+libpng.dll: libpng.bpr
+  $(ROOT)\bin\bpr2mak $**
+  $(ROOT)\bin\make -$(MAKEFLAGS) -f$*.mak
+
+
diff --git a/gs/libpng/projects/cbuilder5/libpng.bpr b/gs/libpng/projects/cbuilder5/libpng.bpr
new file mode 100644
index 000000000..b9fdbe4d0
--- /dev/null
+++ b/gs/libpng/projects/cbuilder5/libpng.bpr
@@ -0,0 +1,157 @@
+<?xml version='1.0' encoding='utf-8' ?>
+<!-- C++Builder XML Project -->
+<PROJECT>
+  <MACROS>
+    <VERSION value="BCB.05.03"/>
+    <PROJECT value="libpng.dll"/>
+    <OBJFILES value="libpng.obj ..\..\pngwutil.obj ..\..\pngerror.obj ..\..\pngget.obj 
+      ..\..\pngmem.obj ..\..\pngpread.obj ..\..\pngread.obj ..\..\pngrio.obj 
+      ..\..\pngrtran.obj ..\..\pngrutil.obj ..\..\pngset.obj ..\..\pngtrans.obj 
+      ..\..\pngwio.obj ..\..\pngwrite.obj ..\..\pngwtran.obj ..\..\png.obj"/>
+    <RESFILES value=""/>
+    <DEFFILE value=""/>
+    <RESDEPEN value="$(RESFILES)"/>
+    <LIBFILES value="..\..\..\zlib\zlib.lib"/>
+    <LIBRARIES value="bcbsmp50.lib dclocx50.lib NMFast50.lib Tee50.lib Vclx50.lib Vcl50.lib"/>
+    <SPARELIBS value="Vcl50.lib Vclx50.lib Tee50.lib NMFast50.lib dclocx50.lib bcbsmp50.lib"/>
+    <PACKAGES value="Vcl50.bpi Vclx50.bpi bcbsmp50.bpi Qrpt50.bpi Vcldb50.bpi Vclbde50.bpi 
+      ibsmp50.bpi vcldbx50.bpi TeeUI50.bpi TeeDB50.bpi Tee50.bpi TeeQR50.bpi 
+      VCLIB50.bpi bcbie50.bpi vclie50.bpi Inetdb50.bpi Inet50.bpi NMFast50.bpi 
+      dclocx50.bpi bcb97axserver50.bpi SIMULUSCOMPONENTS.bpi Simulus2.bpi"/>
+    <PATHCPP value=".;..\.."/>
+    <PATHPAS value=".;"/>
+    <PATHRC value=".;"/>
+    <PATHASM value=".;"/>
+    <DEBUGLIBPATH value="$(BCB)\lib\debug"/>
+    <RELEASELIBPATH value="$(BCB)\lib\release"/>
+    <LINKER value="tlink32"/>
+    <USERDEFINES value="PNG_BUILD_DLL;PNG_NO_MODULEDEF"/>
+    <SYSDEFINES value="NO_STRICT;_NO_VCL;_RTLDLL"/>
+    <MAINSOURCE value="libpng.bpf"/>
+    <INCLUDEPATH value="..\..;..\..\..\zlib;$(BCB)\include"/>
+    <LIBPATH value="..\..;$(BCB)\lib\obj;$(BCB)\lib"/>
+    <WARNINGS value="-w8092 -w8091 -w8090 -w8089 -w8087 -wprc -wucp -wstv -wstu -wsig -wpin 
+      -wnod -wnak -wdef -wcln -wbbf -wasm -wamp -wamb"/>
+  </MACROS>
+  <OPTIONS>
+    <CFLAG1 value="-WD -O2 -w -Vx -Ve -x- -RT- -X- -a8 -5 -b- -d -k- -vi -tWD -tWM -c"/>
+    <PFLAGS value="-$Y- -$L- -$D- -$C- -v -JPHNE -M"/>
+    <RFLAGS value=""/>
+    <AFLAGS value="/mx /w2 /zn"/>
+    <LFLAGS value="-D&quot;&quot; -aa -Tpd -x -Gn -Gi -w"/>
+  </OPTIONS>
+  <LINKER>
+    <ALLOBJ value="c0d32.obj $(OBJFILES)"/>
+    <ALLRES value="$(RESFILES)"/>
+    <ALLLIB value="$(LIBFILES) $(LIBRARIES) import32.lib cw32mti.lib"/>
+  </LINKER>
+  <IDEOPTIONS>
+[Version Info]
+IncludeVerInfo=0
+AutoIncBuild=0
+MajorVer=1
+MinorVer=0
+Release=0
+Build=0
+Debug=0
+PreRelease=0
+Special=0
+Private=0
+DLL=1
+Locale=2057
+CodePage=1252
+
+[Version Info Keys]
+CompanyName=
+FileDescription=
+FileVersion=1.0.0.0
+InternalName=
+LegalCopyright=
+LegalTrademarks=
+OriginalFilename=
+ProductName=
+ProductVersion=
+Comments=
+
+[HistoryLists\hlIncludePath]
+Count=18
+Item0=..\..;..\..\..\zlib;$(BCB)\include
+Item1=..\..;P:\My Documents\Source\PNG+ZLib\zlib;$(BCB)\include
+Item2=..\..;..\Source\ThirdParty\PortableNetworkGraphics\external;..\Source\ThirdParty\PortableNetworkGraphics;..\Source\ThirdParty\ZLibCompression\external;$(BCB)\include
+Item3=..\Source\ThirdParty\PortableNetworkGraphics\external;..\Source\ThirdParty\PortableNetworkGraphics;..\Source\ThirdParty\ZLibCompression\external;$(BCB)\include
+Item4=..\Source\ThirdParty\PortableNetworkGraphics\external;..\Source\ThirdParty\PortableNetworkGraphics;..\Source\ThirdParty\ZLibCompression;$(BCB)\include
+Item5=..\Source\ThirdParty\PortableNetworkGraphics;..\Source\ThirdParty\ZLibCompression;$(BCB)\include
+Item6=..\Source\ThirdParty\PortableNetworkGraphics;P:\Development\Source\ThirdParty\ZLibCompression;$(BCB)\include
+Item7=..\Source\ThirdParty\PortableNetworkGraphics;$(BCB)\include
+Item8=$(BCB)\include
+Item9=..\Source;..\Source\General\Templates;..\Source\SIMUtilities;$(BCB)\include;$(BCB)\include\vcl
+Item10=P:\Development\Source\;P:\Development\Source\General\Templates\;P:\Development\Source\SIMUtilities\;$(BCB)\include;$(BCB)\include\vcl
+Item11=P:\Development\Source;P:\Development\Source\General\Templates\;P:\Development\Source\SIMUtilities\;$(BCB)\include;$(BCB)\include\vcl
+Item12=P:\Development\Source\General\Templates\;P:\Development\Source\SIMUtilities\;$(BCB)\include;$(BCB)\include\vcl
+Item13=P:\Development\Source\General\Templates\;P:\Development\Source\SIMUtilities;$(BCB)\include;$(BCB)\include\vcl
+Item14=P:\Development\Source\General\Templates\;$(BCB)\include;$(BCB)\include\vcl
+Item15=P:\Development\Source\General\Templates;$(BCB)\include;$(BCB)\include\vcl
+Item16=P:\Development\Source;$(BCB)\include;$(BCB)\include\vcl
+Item17=$(BCB)\include;$(BCB)\include\vcl
+
+[HistoryLists\hlLibraryPath]
+Count=10
+Item0=..\..;$(BCB)\lib\obj;$(BCB)\lib
+Item1=..\..;..\Source\ThirdParty\PortableNetworkGraphics\external;..\Source\ThirdParty\PortableNetworkGraphics;$(BCB)\lib\obj;$(BCB)\lib
+Item2=..\Source\ThirdParty\PortableNetworkGraphics\external;..\Source\ThirdParty\PortableNetworkGraphics;$(BCB)\lib\obj;$(BCB)\lib
+Item3=..\Source\ThirdParty\PortableNetworkGraphics;$(BCB)\lib\obj;$(BCB)\lib
+Item4=$(BCB)\lib\obj;$(BCB)\lib
+Item5=..\Source\SIMUtilities;..\Source;$(BCB)\lib\obj;$(BCB)\lib
+Item6=P:\Development\Source\SIMUtilities\;P:\Development\Source\;$(BCB)\lib\obj;$(BCB)\lib
+Item7=P:\Development\Source\SIMUtilities;P:\Development\Source\;$(BCB)\lib\obj;$(BCB)\lib
+Item8=P:\Development\Source\;$(BCB)\lib\obj;$(BCB)\lib
+Item9=P:\Development\Source;$(BCB)\lib\obj;$(BCB)\lib
+
+[HistoryLists\hlDebugSourcePath]
+Count=1
+Item0=$(BCB)\source\vcl
+
+[HistoryLists\hlConditionals]
+Count=20
+Item0=ZLIB_DLL;Z_PREFIX;PNG_BUILD_DLL;PNG_NO_MODULEDEF
+Item1=_DEBUG;ZLIB_DLL;Z_PREFIX;PNG_BUILD_DLL;PNG_NO_MODULEDEF
+Item2=PNG_BUILD_DLL;ZLIB_DLL;_DEBUG;PNG_NO_MODULEDEF
+Item3=PNG_BUILD_DLL;ZLIB_DLL;_DEBUG;PNG_DEBUG=5;PNG_NO_MODULEDEF;PNG_NO_GLOBAL_ARRAYS
+Item4=PNG_BUILD_DLL;ZLIB_DLL;_DEBUG;PNG_DEBUG=5;PNG_NO_MODULEDEF;PNG_SETJMP_NOT_SUPPORTED;PNG_DEBUG_FILE=stderr
+Item5=PNG_BUILD_DLL;ZLIB_DLL;_DEBUG;PNG_DEBUG;PNG_NO_MODULEDEF;PNG_SETJMP_NOT_SUPPORTED
+Item6=PNG_BUILD_DLL;ZLIB_DLL;_DEBUG;PNG_DEBUG=5;PNG_NO_MODULEDEF;PNG_SETJMP_NOT_SUPPORTED
+Item7=PNG_BUILD_DLL;ZLIB_DLL;_DEBUG;PNG_DEBUG=5;PNG_NO_MODULEDEF
+Item8=PNG_BUILD_DLL;ZLIB_DLL;_DEBUG;PNG_DEBUG=5
+Item9=PNG_BUILD_DLL;ZLIB_DLL;_DEBUG
+Item10=PNG_BUILD_DLL;ZLIB_DLL
+Item11=PNG_BUILD_DLL
+Item12=PNG_DLL;PNG_BUILD_DLL;ZLIB_DLL
+Item13=PNG_DLL;PNG_BUILD_DLL;PNG_NO_GLOBAL_ARRAYS;ZLIB_DLL
+Item14=PNG_DLL;PNG_BUILD_DLL;PNG_NO_GLOBAL_ARRAYS
+Item15=PNG_DLL;PNG_BUILD_DLL
+Item16=PNG_DLL;PNG_BUILD_DLL;PNG_MODULEDEF
+Item17=_HTML_FORM
+Item18=_DEBUG;_HTML_FORM
+Item19=_DEBUG
+
+[HistoryLists\hlIntOutputDir]
+Count=2
+Item0=..\Obj
+Item1=P:\Development\Obj
+
+[Debugging]
+DebugSourceDirs=
+
+[Parameters]
+RunParams=
+HostApplication=P:\Development\Executables\LibPNGTestApp.exe
+RemoteHost=
+RemotePath=
+RemoteDebug=0
+
+[Compiler]
+ShowInfoMsgs=0
+LinkDebugVcl=0
+LinkCGLIB=0
+  </IDEOPTIONS>
+</PROJECT>
\ No newline at end of file
diff --git a/gs/libpng/projects/cbuilder5/libpng.cpp b/gs/libpng/projects/cbuilder5/libpng.cpp
new file mode 100644
index 000000000..4e2f274d4
--- /dev/null
+++ b/gs/libpng/projects/cbuilder5/libpng.cpp
@@ -0,0 +1,29 @@
+//---------------------------------------------------------------------------
+#include <windows.h>
+//---------------------------------------------------------------------------
+//   Important note about DLL memory management when your DLL uses the
+//   static version of the RunTime Library:
+//
+//   If your DLL exports any functions that pass String objects (or structs/
+//   classes containing nested Strings) as parameter or function results,
+//   you will need to add the library MEMMGR.LIB to both the DLL project and
+//   any other projects that use the DLL.  You will also need to use MEMMGR.LIB
+//   if any other projects which use the DLL will be performing new or delete
+//   operations on any non-TObject-derived classes which are exported from the
+//   DLL. Adding MEMMGR.LIB to your project will change the DLL and its calling
+//   EXE's to use the BORLNDMM.DLL as their memory manager.  In these cases,
+//   the file BORLNDMM.DLL should be deployed along with your DLL.
+//
+//   To avoid using BORLNDMM.DLL, pass string information using "char *" or
+//   ShortString parameters.
+//
+//   If your DLL uses the dynamic version of the RTL, you do not need to
+//   explicitly add MEMMGR.LIB as this will be done implicitly for you
+//---------------------------------------------------------------------------
+
+int WINAPI DllEntryPoint(HINSTANCE, unsigned long, void*)
+{
+    return 1;
+}
+//---------------------------------------------------------------------------
+ 
\ No newline at end of file
diff --git a/gs/libpng/projects/cbuilder5/libpng.readme.txt b/gs/libpng/projects/cbuilder5/libpng.readme.txt
new file mode 100644
index 000000000..c99c1e9a7
--- /dev/null
+++ b/gs/libpng/projects/cbuilder5/libpng.readme.txt
@@ -0,0 +1,25 @@
+Project files to build libpng using Borland C++ Builder v5.0
+
+In order to build and use libpng, please follow these steps:
+
+ 1). Install zlib in a directory at the same level with libpng.
+
+ 2). In a console window, go to the zlib directory and type:
+       make -f win32\Makefile.bor
+     After performing this step, you should have a file named
+     zlib.lib in the zlib directory.
+
+ 3). Add the following conditional define to your project:
+       PNG_USE_DLL
+
+ 4). Add libpng.lib or libpngstat.lib to the project.
+     Build the project.
+
+ 5). If the build fails, add the paths to png.h and zlib.h to
+     your include path, and restart the build.
+
+By default, the libpng project uses zlib as a static library.  If
+you wish to use zlib as a DLL, please read the important notes from
+the zlib DLL FAQ, found inside the zlib distribution.
+
+See the libpng documentation for instructions on how to use the code.
diff --git a/gs/libpng/projects/cbuilder5/libpngstat.bpf b/gs/libpng/projects/cbuilder5/libpngstat.bpf
new file mode 100644
index 000000000..fbc5c406c
--- /dev/null
+++ b/gs/libpng/projects/cbuilder5/libpngstat.bpf
@@ -0,0 +1,22 @@
+USEUNIT("..\..\png.c");
+USEUNIT("..\..\pngerror.c");
+USEUNIT("..\..\pngget.c");
+USEUNIT("..\..\pngmem.c");
+USEUNIT("..\..\pngpread.c");
+USEUNIT("..\..\pngread.c");
+USEUNIT("..\..\pngrio.c");
+USEUNIT("..\..\pngrtran.c");
+USEUNIT("..\..\pngrutil.c");
+USEUNIT("..\..\pngset.c");
+USEUNIT("..\..\pngtrans.c");
+USEUNIT("..\..\pngwio.c");
+USEUNIT("..\..\pngwrite.c");
+USEUNIT("..\..\pngwtran.c");
+USEUNIT("..\..\pngwutil.c");
+USELIB("..\..\..\zlib\zlib.lib");
+//---------------------------------------------------------------------------
+#define Library
+
+// To add a file to the library use the Project menu 'Add to Project'.
+
+ 
\ No newline at end of file
diff --git a/gs/libpng/projects/cbuilder5/libpngstat.bpr b/gs/libpng/projects/cbuilder5/libpngstat.bpr
new file mode 100644
index 000000000..9a51ecc88
--- /dev/null
+++ b/gs/libpng/projects/cbuilder5/libpngstat.bpr
@@ -0,0 +1,109 @@
+<?xml version='1.0' encoding='utf-8' ?>
+<!-- C++Builder XML Project -->
+<PROJECT>
+  <MACROS>
+    <VERSION value="BCB.05.03"/>
+    <PROJECT value="libpngstat.lib"/>
+    <OBJFILES value="..\..\pngerror.obj ..\..\png.obj ..\..\pngwutil.obj ..\..\pngmem.obj 
+      ..\..\pngpread.obj ..\..\pngread.obj ..\..\pngrio.obj ..\..\pngrtran.obj 
+      ..\..\pngrutil.obj ..\..\pngset.obj ..\..\pngtrans.obj ..\..\pngwio.obj 
+      ..\..\pngwrite.obj ..\..\pngwtran.obj ..\..\pngget.obj"/>
+    <RESFILES value=""/>
+    <DEFFILE value=""/>
+    <RESDEPEN value="$(RESFILES)"/>
+    <LIBFILES value="..\..\..\zlib\zlib.lib"/>
+    <LIBRARIES value=""/>
+    <PACKAGES value=""/>
+    <PATHCPP value=".;..\.."/>
+    <PATHPAS value=".;"/>
+    <PATHRC value=".;"/>
+    <PATHASM value=".;"/>
+    <LINKER value="TLib"/>
+    <USERDEFINES value=""/>
+    <SYSDEFINES value="_RTLDLL;NO_STRICT"/>
+    <MAINSOURCE value="libpngstat.bpf"/>
+    <INCLUDEPATH value="..\..;..\..\..\zlib;$(BCB)\include"/>
+    <LIBPATH value="..\..;$(BCB)\lib\obj;$(BCB)\lib"/>
+    <WARNINGS value="-w-par"/>
+    <LISTFILE value=""/>
+  </MACROS>
+  <OPTIONS>
+    <CFLAG1 value="-O2 -w -Vx -Ve -X- -a8 -5 -b- -d -k- -vi -c -tW -tWM"/>
+    <PFLAGS value="-$Y- -$L- -$D- -$C- -v -JPHNE -M"/>
+    <AFLAGS value="/mx /w2 /zn"/>
+    <LFLAGS value=""/>
+  </OPTIONS>
+  <LINKER>
+    <ALLOBJ value="$(OBJFILES)"/>
+    <ALLLIB value=""/>
+  </LINKER>
+  <IDEOPTIONS>
+[Version Info]
+IncludeVerInfo=0
+AutoIncBuild=0
+MajorVer=1
+MinorVer=0
+Release=0
+Build=0
+Debug=0
+PreRelease=0
+Special=0
+Private=0
+DLL=0
+Locale=2057
+CodePage=1252
+
+[Version Info Keys]
+CompanyName=
+FileDescription=
+FileVersion=1.0.0.0
+InternalName=
+LegalCopyright=
+LegalTrademarks=
+OriginalFilename=
+ProductName=
+ProductVersion=1.0.0.0
+Comments=
+
+[HistoryLists\hlIncludePath]
+Count=2
+Item0=..\..;P:\My Documents\Source\PNG+ZLib\zlib;$(BCB)\include
+Item1=..\..;$(BCB)\include;$(BCB)\include\vcl
+
+[HistoryLists\hlLibraryPath]
+Count=1
+Item0=..\..;$(BCB)\lib\obj;$(BCB)\lib
+
+[HistoryLists\hlDebugSourcePath]
+Count=1
+Item0=$(BCB)\source\vcl
+
+[HistoryLists\hlConditionals]
+Count=1
+Item0=_DEBUG
+
+[HistoryLists\hlTlibPageSize]
+Count=1
+Item0=0x0010
+
+[Debugging]
+DebugSourceDirs=$(BCB)\source\vcl
+
+[Parameters]
+RunParams=
+HostApplication=
+RemoteHost=
+RemotePath=
+RemoteDebug=0
+
+[Compiler]
+ShowInfoMsgs=0
+LinkDebugVcl=0
+LinkCGLIB=0
+
+[Language]
+ActiveLang=
+ProjectLang=
+RootDir=
+  </IDEOPTIONS>
+</PROJECT>
\ No newline at end of file
diff --git a/gs/libpng/projects/cbuilder5/zlib.readme.txt b/gs/libpng/projects/cbuilder5/zlib.readme.txt
new file mode 100644
index 000000000..cb6a7a81e
--- /dev/null
+++ b/gs/libpng/projects/cbuilder5/zlib.readme.txt
@@ -0,0 +1,14 @@
+The project that builds libpng under Borland C++ Builder does not
+explicitly build zlib.  By taking this decision, there is no need
+to update the libpng project each time when there is a change in
+the list of zlib source files.  After all, this list is private to
+zlib, and applications (such as libpng) should not assume anything
+about it.
+
+If you wish to contribute a project that builds zlib under Borland
+C++ Builder, please submit it to the zlib developers, not to the
+libpng developers.
+
+By default, the libpng project uses zlib as a static library.  If
+you wish to use zlib as a DLL, please read the important notes from
+the zlib DLL FAQ, found inside the zlib distribution.
diff --git a/gs/libpng/projects/netware.txt b/gs/libpng/projects/netware.txt
new file mode 100644
index 000000000..178361da8
--- /dev/null
+++ b/gs/libpng/projects/netware.txt
@@ -0,0 +1,6 @@
+A set of project files is available for Netware.  Get
+libpng-1.2.5-project-netware.zip from a libpng distribution
+site such as http://libpng.sourceforge.net
+
+Put the zip file in this directory (projects) and then run
+"unzip -a libpng-1.2.5-project-netware.zip"
diff --git a/gs/libpng/projects/visualc6/README.txt b/gs/libpng/projects/visualc6/README.txt
new file mode 100644
index 000000000..d34980d57
--- /dev/null
+++ b/gs/libpng/projects/visualc6/README.txt
@@ -0,0 +1,57 @@
+Microsoft Developer Studio Project File, Format Version 6.00 for libpng.
+
+Copyright (C) 2000-2004 Simon-Pierre Cadieux.
+Copyright (C) 2004 Cosmin Truta.
+For conditions of distribution and use, see copyright notice in png.h
+
+
+Assumptions:
+* The libpng source files are in ..\..
+* The zlib source files are in ..\..\..\zlib
+* The zlib project files are in ..\..\..\zlib\projects\visualc6
+
+
+To use:
+
+1) On the main menu, select "File | Open Workspace".
+   Open "libpng.dsw".
+
+2) Select "Build | Set Active Configuration".
+   Choose the configuration you wish to build.
+   (Choose libpng or pngtest; zlib will be built automatically.)
+
+3) Select "Build | Clean".
+
+4) Select "Build | Build ... (F7)".  Ignore warning messages about
+   not being able to find certain include files (e.g. alloc.h).
+
+5) If you built the sample program (pngtest),
+   select "Build | Execute ... (Ctrl+F5)".
+
+
+This project builds the libpng binaries as follows:
+
+* Win32_DLL_Release\libpng13.dll      DLL build
+* Win32_DLL_Debug\libpng13d.dll       DLL build (debug version)
+* Win32_DLL_ASM_Release\libpng13.dll  DLL build using ASM code
+* Win32_DLL_ASM_Debug\libpng13d.dll   DLL build using ASM (debug version)
+* Win32_DLL_VB\libpng13vb.dll         DLL build for Visual Basic, using stdcall
+* Win32_LIB_Release\libpng.lib        static build
+* Win32_LIB_Debug\libpngd.lib         static build (debug version)
+* Win32_LIB_ASM_Release\libpng.lib    static build using ASM code
+* Win32_LIB_ASM_Debug\libpngd.lib     static build using ASM (debug version)
+
+
+Notes:
+
+If you change anything in the source files, or select different compiler
+settings, please change the DLL name to something different than any of
+the above names. Also, make sure that in your "pngusr.h" you define
+PNG_USER_PRIVATEBUILD and PNG_USER_DLLFNAME_POSTFIX according to the
+instructions provided in "pngconf.h".
+
+All DLLs built by this project use the Microsoft dynamic C runtime library
+MSVCRT.DLL (MSVCRTD.DLL for debug versions).  If you distribute any of the
+above mentioned libraries you should also include this DLL in your package.
+For a list of files that are redistributable in Visual C++ 6.0, see
+Common\Redist\Redist.txt on Disc 1 of the Visual C++ 6.0 product CDs.
diff --git a/gs/libpng/projects/visualc6/libpng.dsp b/gs/libpng/projects/visualc6/libpng.dsp
new file mode 100644
index 000000000..1992c2b98
--- /dev/null
+++ b/gs/libpng/projects/visualc6/libpng.dsp
@@ -0,0 +1,507 @@
+# Microsoft Developer Studio Project File - Name="libpng" - Package Owner=<4>
+# Microsoft Developer Studio Generated Build File, Format Version 6.00
+# ** DO NOT EDIT **
+
+# TARGTYPE "Win32 (x86) Dynamic-Link Library" 0x0102
+# TARGTYPE "Win32 (x86) Static Library" 0x0104
+
+CFG=libpng - Win32 DLL Release
+!MESSAGE This is not a valid makefile. To build this project using NMAKE,
+!MESSAGE use the Export Makefile command and run
+!MESSAGE
+!MESSAGE NMAKE /f "libpng.mak".
+!MESSAGE
+!MESSAGE You can specify a configuration when running NMAKE
+!MESSAGE by defining the macro CFG on the command line. For example:
+!MESSAGE
+!MESSAGE NMAKE /f "libpng.mak" CFG="libpng - Win32 DLL Release"
+!MESSAGE
+!MESSAGE Possible choices for configuration are:
+!MESSAGE
+!MESSAGE "libpng - Win32 DLL Release" (based on "Win32 (x86) Dynamic-Link Library")
+!MESSAGE "libpng - Win32 DLL Debug" (based on "Win32 (x86) Dynamic-Link Library")
+!MESSAGE "libpng - Win32 DLL ASM Release" (based on "Win32 (x86) Dynamic-Link Library")
+!MESSAGE "libpng - Win32 DLL ASM Debug" (based on "Win32 (x86) Dynamic-Link Library")
+!MESSAGE "libpng - Win32 DLL VB" (based on "Win32 (x86) Dynamic-Link Library")
+!MESSAGE "libpng - Win32 LIB Release" (based on "Win32 (x86) Static Library")
+!MESSAGE "libpng - Win32 LIB Debug" (based on "Win32 (x86) Static Library")
+!MESSAGE "libpng - Win32 LIB ASM Release" (based on "Win32 (x86) Static Library")
+!MESSAGE "libpng - Win32 LIB ASM Debug" (based on "Win32 (x86) Static Library")
+!MESSAGE
+
+# Begin Project
+# PROP AllowPerConfigDependencies 0
+# PROP Scc_ProjName ""
+# PROP Scc_LocalPath ""
+
+!IF  "$(CFG)" == "libpng - Win32 DLL Release"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 0
+# PROP BASE Output_Dir "libpng___Win32_DLL_Release"
+# PROP BASE Intermediate_Dir "libpng___Win32_DLL_Release"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 0
+# PROP Output_Dir "Win32_DLL_Release"
+# PROP Intermediate_Dir "Win32_DLL_Release"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+CPP=cl.exe
+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT BASE CPP /YX /Yc /Yu
+# ADD CPP /nologo /MD /W3 /O2 /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "NDEBUG" /D "PNG_BUILD_DLL" /D "ZLIB_DLL" /FD /c
+# SUBTRACT CPP /YX /Yc /Yu
+MTL=midl.exe
+# ADD BASE MTL /nologo /D "NDEBUG" /mktyplib203 /win32
+# ADD MTL /nologo /D "NDEBUG" /mktyplib203 /win32
+RSC=rc.exe
+# ADD BASE RSC /l 0x409 /d "NDEBUG"
+# ADD RSC /l 0x409 /i "..\.." /d "NDEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /dll /machine:I386
+# ADD LINK32 zlib1.lib /nologo /dll /machine:I386 /out:"Win32_DLL_Release\libpng13.dll" /libpath:"..\..\..\zlib\projects\visualc6\Win32_DLL_Release"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL Debug"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 1
+# PROP BASE Output_Dir "libpng___Win32_DLL_Release"
+# PROP BASE Intermediate_Dir "libpng___Win32_DLL_Release"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 1
+# PROP Output_Dir "Win32_DLL_Debug"
+# PROP Intermediate_Dir "Win32_DLL_Debug"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+CPP=cl.exe
+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c
+# SUBTRACT BASE CPP /YX /Yc /Yu
+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "_DEBUG" /D "DEBUG" /D PNG_DEBUG=1 /D "PNG_BUILD_DLL" /D "ZLIB_DLL" /FD /GZ /c
+# SUBTRACT CPP /YX /Yc /Yu
+MTL=midl.exe
+# ADD BASE MTL /nologo /D "_DEBUG" /mktyplib203 /win32
+# ADD MTL /nologo /D "_DEBUG" /mktyplib203 /win32
+RSC=rc.exe
+# ADD BASE RSC /l 0x409 /d "_DEBUG"
+# ADD RSC /l 0x409 /i "..\.." /d "_DEBUG" /d PNG_DEBUG=1
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /dll /debug /machine:I386 /pdbtype:sept
+# ADD LINK32 zlib1d.lib /nologo /dll /debug /machine:I386 /out:"Win32_DLL_Debug\libpng13d.dll" /libpath:"..\..\..\zlib\projects\visualc6\Win32_DLL_Debug"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL ASM Release"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 0
+# PROP BASE Output_Dir "libpng___Win32_DLL_ASM_Release"
+# PROP BASE Intermediate_Dir "libpng___Win32_DLL_ASM_Release"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 0
+# PROP Output_Dir "Win32_DLL_ASM_Release"
+# PROP Intermediate_Dir "Win32_DLL_ASM_Release"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+CPP=cl.exe
+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT BASE CPP /YX /Yc /Yu
+# ADD CPP /nologo /MD /W3 /O2 /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "NDEBUG" /D "PNG_USE_PNGVCRD" /D "PNG_BUILD_DLL" /D "ZLIB_DLL" /D "PNG_LIBPNG_SPECIALBUILD" /FD /c
+# SUBTRACT CPP /YX /Yc /Yu
+MTL=midl.exe
+# ADD BASE MTL /nologo /D "NDEBUG" /mktyplib203 /win32
+# ADD MTL /nologo /D "NDEBUG" /mktyplib203 /win32
+RSC=rc.exe
+# ADD BASE RSC /l 0x409 /d "NDEBUG"
+# ADD RSC /l 0x409 /i "..\.." /d "NDEBUG" /d PNG_LIBPNG_SPECIALBUILD=""""Use MMX instructions""""
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /dll /machine:I386
+# ADD LINK32 zlib1.lib /nologo /dll /machine:I386 /out:"Win32_DLL_ASM_Release\libpng13.dll" /libpath:"..\..\..\zlib\projects\visualc6\Win32_DLL_ASM_Release"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL ASM Debug"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 1
+# PROP BASE Output_Dir "libpng___Win32_DLL_ASM_Debug"
+# PROP BASE Intermediate_Dir "libpng___Win32_DLL_ASM_Debug"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 1
+# PROP Output_Dir "Win32_DLL_ASM_Debug"
+# PROP Intermediate_Dir "Win32_DLL_ASM_Debug"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+CPP=cl.exe
+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c
+# SUBTRACT BASE CPP /YX /Yc /Yu
+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "_DEBUG" /D "DEBUG" /D PNG_DEBUG=1 /D "PNG_USE_PNGVCRD" /D "PNG_BUILD_DLL" /D "ZLIB_DLL" /D "PNG_LIBPNG_SPECIALBUILD" /FD /GZ /c
+# SUBTRACT CPP /YX /Yc /Yu
+MTL=midl.exe
+# ADD BASE MTL /nologo /D "_DEBUG" /mktyplib203 /win32
+# ADD MTL /nologo /D "_DEBUG" /mktyplib203 /win32
+RSC=rc.exe
+# ADD BASE RSC /l 0x409 /d "_DEBUG"
+# ADD RSC /l 0x409 /i "..\.." /d "_DEBUG" /d PNG_DEBUG=1 /d PNG_LIBPNG_SPECIALBUILD=""""Use MMX instructions""""
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /dll /debug /machine:I386 /pdbtype:sept
+# ADD LINK32 zlib1d.lib /nologo /dll /debug /machine:I386 /out:"Win32_DLL_ASM_Debug\libpng13d.dll" /libpath:"..\..\..\zlib\projects\visualc6\Win32_DLL_ASM_Debug"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL VB"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 0
+# PROP BASE Output_Dir "libpng___Win32_DLL_VB"
+# PROP BASE Intermediate_Dir "libpng___Win32_DLL_VB"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 0
+# PROP Output_Dir "Win32_DLL_VB"
+# PROP Intermediate_Dir "Win32_DLL_VB"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+CPP=cl.exe
+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT BASE CPP /YX /Yc /Yu
+# ADD CPP /nologo /MD /W3 /O2 /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "NDEBUG" /D "PNG_BUILD_DLL" /D "ZLIB_DLL" /D PNGAPI=__stdcall /D "PNG_NO_MODULEDEF" /D "PNG_LIBPNG_SPECIALBUILD" /FD /c
+# SUBTRACT CPP /YX /Yc /Yu
+MTL=midl.exe
+# ADD BASE MTL /nologo /D "NDEBUG" /mktyplib203 /win32
+# ADD MTL /nologo /D "NDEBUG" /mktyplib203 /win32
+RSC=rc.exe
+# ADD BASE RSC /l 0x409 /d "NDEBUG"
+# ADD RSC /l 0x409 /i "..\.." /d "NDEBUG" /dPNG_LIBPNG_DLLFNAME_POSTFIX=""""VB"""" /dPNG_LIBPNG_SPECIALBUILD=""""__stdcall calling convention used for exported functions""""
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /dll /machine:I386
+# ADD LINK32 zlib1.lib /nologo /dll /machine:I386 /out:"Win32_DLL_VB\libpng13vb.dll" /libpath:"..\..\..\zlib\projects\visualc6\Win32_DLL_Release"
+# Begin Special Build Tool
+OutDir=.\Win32_DLL_VB
+TargetName=libpng13vb
+SOURCE="$(InputPath)"
+PostBuild_Cmds=echo    Deleting $(targetname) import library and export file (Not required for VB projects)	del $(outdir)\$(targetname).lib	del $(outdir)\$(targetname).exp
+# End Special Build Tool
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB Release"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 0
+# PROP BASE Output_Dir "libpng___Win32_LIB_Release"
+# PROP BASE Intermediate_Dir "libpng___Win32_LIB_Release"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 0
+# PROP Output_Dir "Win32_LIB_Release"
+# PROP Intermediate_Dir "Win32_LIB_Release"
+# PROP Target_Dir ""
+CPP=cl.exe
+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT BASE CPP /YX /Yc /Yu
+# ADD CPP /nologo /MD /W3 /O2 /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT CPP /YX /Yc /Yu
+RSC=rc.exe
+# ADD BASE RSC /l 0x409 /d "NDEBUG"
+# ADD RSC /l 0x409 /i "..\.." /d "NDEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LIB32=link.exe -lib
+# ADD BASE LIB32 /nologo
+# ADD LIB32 /nologo
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB Debug"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 1
+# PROP BASE Output_Dir "libpng___Win32_LIB_Debug"
+# PROP BASE Intermediate_Dir "libpng___Win32_LIB_Debug"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 1
+# PROP Output_Dir "Win32_LIB_Debug"
+# PROP Intermediate_Dir "Win32_LIB_Debug"
+# PROP Target_Dir ""
+CPP=cl.exe
+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c
+# SUBTRACT BASE CPP /YX /Yc /Yu
+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "_DEBUG" /D "DEBUG" /D PNG_DEBUG=1 /FD /GZ /c
+# SUBTRACT CPP /YX /Yc /Yu
+RSC=rc.exe
+# ADD BASE RSC /l 0x409 /d "_DEBUG"
+# ADD RSC /l 0x409 /d "_DEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LIB32=link.exe -lib
+# ADD BASE LIB32 /nologo
+# ADD LIB32 /nologo /out:"Win32_LIB_Debug\libpngd.lib"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB ASM Release"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 0
+# PROP BASE Output_Dir "libpng___Win32_LIB_ASM_Release"
+# PROP BASE Intermediate_Dir "libpng___Win32_LIB_ASM_Release"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 0
+# PROP Output_Dir "Win32_LIB_ASM_Release"
+# PROP Intermediate_Dir "Win32_LIB_ASM_Release"
+# PROP Target_Dir ""
+CPP=cl.exe
+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT BASE CPP /YX /Yc /Yu
+# ADD CPP /nologo /MD /W3 /O2 /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "NDEBUG" /D "PNG_USE_PNGVCRD" /D "PNG_LIBPNG_SPECIALBUILD" /FD /c
+# SUBTRACT CPP /YX /Yc /Yu
+RSC=rc.exe
+# ADD BASE RSC /l 0x409 /d "NDEBUG"
+# ADD RSC /l 0x409 /i "..\.." /d "NDEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LIB32=link.exe -lib
+# ADD BASE LIB32 /nologo
+# ADD LIB32 /nologo
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB ASM Debug"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 1
+# PROP BASE Output_Dir "libpng___Win32_LIB_ASM_Debug"
+# PROP BASE Intermediate_Dir "libpng___Win32_LIB_ASM_Debug"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 1
+# PROP Output_Dir "Win32_LIB_ASM_Debug"
+# PROP Intermediate_Dir "Win32_LIB_ASM_Debug"
+# PROP Target_Dir ""
+CPP=cl.exe
+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c
+# SUBTRACT BASE CPP /YX /Yc /Yu
+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /I "..\.." /I "..\..\..\zlib" /D "WIN32" /D "_DEBUG" /D "DEBUG" /D PNG_DEBUG=1 /D "PNG_USE_PNGVCRD" /D "PNG_LIBPNG_SPECIALBUILD" /FD /GZ /c
+# SUBTRACT CPP /YX /Yc /Yu
+RSC=rc.exe
+# ADD BASE RSC /l 0x409 /d "_DEBUG"
+# ADD RSC /l 0x409 /d "_DEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LIB32=link.exe -lib
+# ADD BASE LIB32 /nologo
+# ADD LIB32 /nologo /out:"Win32_LIB_ASM_Debug\libpngd.lib"
+
+!ENDIF
+
+# Begin Target
+
+# Name "libpng - Win32 DLL Release"
+# Name "libpng - Win32 DLL Debug"
+# Name "libpng - Win32 DLL ASM Release"
+# Name "libpng - Win32 DLL ASM Debug"
+# Name "libpng - Win32 DLL VB"
+# Name "libpng - Win32 LIB Release"
+# Name "libpng - Win32 LIB Debug"
+# Name "libpng - Win32 LIB ASM Release"
+# Name "libpng - Win32 LIB ASM Debug"
+# Begin Group "Source Files"
+
+# PROP Default_Filter "cpp;c;cxx;rc;def;r;odl;idl;hpj;bat"
+# Begin Source File
+
+SOURCE=..\..\png.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngerror.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngget.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngmem.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngpread.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngread.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngrio.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngrtran.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngrutil.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngset.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngtrans.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngvcrd.c
+
+!IF  "$(CFG)" == "libpng - Win32 DLL Release"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL Debug"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL ASM Release"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL ASM Debug"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL VB"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB Release"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB Debug"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB ASM Release"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB ASM Debug"
+
+!ENDIF
+
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\scripts\pngw32.def
+
+!IF  "$(CFG)" == "libpng - Win32 DLL Release"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL Debug"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL ASM Release"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL ASM Debug"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL VB"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB Release"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB Debug"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB ASM Release"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB ASM Debug"
+
+# PROP Exclude_From_Build 1
+
+!ENDIF
+
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngwio.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngwrite.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngwtran.c
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngwutil.c
+# End Source File
+# End Group
+# Begin Group "Header Files"
+
+# PROP Default_Filter "h;hpp;hxx;hm;inl"
+# Begin Source File
+
+SOURCE=..\..\png.h
+# End Source File
+# Begin Source File
+
+SOURCE=..\..\pngconf.h
+# End Source File
+# End Group
+# Begin Group "Resource Files"
+
+# PROP Default_Filter "ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe"
+# Begin Source File
+
+SOURCE=..\..\scripts\pngw32.rc
+
+!IF  "$(CFG)" == "libpng - Win32 DLL Release"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL Debug"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL ASM Release"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL ASM Debug"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 DLL VB"
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB Release"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB Debug"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB ASM Release"
+
+# PROP Exclude_From_Build 1
+
+!ELSEIF  "$(CFG)" == "libpng - Win32 LIB ASM Debug"
+
+# PROP Exclude_From_Build 1
+
+!ENDIF
+
+# End Source File
+# End Group
+# Begin Source File
+
+SOURCE=.\README.txt
+# End Source File
+# End Target
+# End Project
diff --git a/gs/libpng/projects/visualc6/libpng.dsw b/gs/libpng/projects/visualc6/libpng.dsw
new file mode 100644
index 000000000..4f3856fbb
--- /dev/null
+++ b/gs/libpng/projects/visualc6/libpng.dsw
@@ -0,0 +1,59 @@
+Microsoft Developer Studio Workspace File, Format Version 6.00
+# WARNING: DO NOT EDIT OR DELETE THIS WORKSPACE FILE!
+
+###############################################################################
+
+Project: "libpng"=".\libpng.dsp" - Package Owner=<4>
+
+Package=<5>
+{{{
+}}}
+
+Package=<4>
+{{{
+    Begin Project Dependency
+    Project_Dep_Name zlib
+    End Project Dependency
+}}}
+
+###############################################################################
+
+Project: "pngtest"=".\pngtest.dsp" - Package Owner=<4>
+
+Package=<5>
+{{{
+}}}
+
+Package=<4>
+{{{
+    Begin Project Dependency
+    Project_Dep_Name libpng
+    End Project Dependency
+}}}
+
+###############################################################################
+
+Project: "zlib"="..\..\..\zlib\projects\visualc6\zlib.dsp" - Package Owner=<4>
+
+Package=<5>
+{{{
+}}}
+
+Package=<4>
+{{{
+}}}
+
+###############################################################################
+
+Global:
+
+Package=<5>
+{{{
+}}}
+
+Package=<3>
+{{{
+}}}
+
+###############################################################################
+
diff --git a/gs/libpng/projects/visualc6/pngtest.dsp b/gs/libpng/projects/visualc6/pngtest.dsp
new file mode 100644
index 000000000..a1be73cd0
--- /dev/null
+++ b/gs/libpng/projects/visualc6/pngtest.dsp
@@ -0,0 +1,314 @@
+# Microsoft Developer Studio Project File - Name="pngtest" - Package Owner=<4>
+# Microsoft Developer Studio Generated Build File, Format Version 6.00
+# ** DO NOT EDIT **
+
+# TARGTYPE "Win32 (x86) Console Application" 0x0103
+
+CFG=pngtest - Win32 DLL Release
+!MESSAGE This is not a valid makefile. To build this project using NMAKE,
+!MESSAGE use the Export Makefile command and run
+!MESSAGE 
+!MESSAGE NMAKE /f "pngtest.mak".
+!MESSAGE 
+!MESSAGE You can specify a configuration when running NMAKE
+!MESSAGE by defining the macro CFG on the command line. For example:
+!MESSAGE 
+!MESSAGE NMAKE /f "pngtest.mak" CFG="pngtest - Win32 DLL Release"
+!MESSAGE 
+!MESSAGE Possible choices for configuration are:
+!MESSAGE 
+!MESSAGE "pngtest - Win32 DLL Release" (based on "Win32 (x86) Console Application")
+!MESSAGE "pngtest - Win32 DLL Debug" (based on "Win32 (x86) Console Application")
+!MESSAGE "pngtest - Win32 DLL ASM Release" (based on "Win32 (x86) Console Application")
+!MESSAGE "pngtest - Win32 DLL ASM Debug" (based on "Win32 (x86) Console Application")
+!MESSAGE "pngtest - Win32 LIB Release" (based on "Win32 (x86) Console Application")
+!MESSAGE "pngtest - Win32 LIB Debug" (based on "Win32 (x86) Console Application")
+!MESSAGE "pngtest - Win32 LIB ASM Release" (based on "Win32 (x86) Console Application")
+!MESSAGE "pngtest - Win32 LIB ASM Debug" (based on "Win32 (x86) Console Application")
+!MESSAGE 
+
+# Begin Project
+# PROP AllowPerConfigDependencies 0
+# PROP Scc_ProjName ""
+# PROP Scc_LocalPath ""
+CPP=cl.exe
+RSC=rc.exe
+
+!IF  "$(CFG)" == "pngtest - Win32 DLL Release"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 0
+# PROP BASE Output_Dir "pngtest___Win32_DLL_Release"
+# PROP BASE Intermediate_Dir "pngtest___Win32_DLL_Release"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 0
+# PROP Output_Dir "Win32_DLL_Release"
+# PROP Intermediate_Dir "Win32_DLL_Release"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+# ADD BASE CPP /nologo /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT BASE CPP /YX
+# ADD CPP /nologo /MD /W3 /O2 /I "..\..\..\zlib" /D "WIN32" /D "NDEBUG" /D "PNG_DLL" /D "PNG_NO_STDIO" /D "PNG_NO_GLOBAL_ARRAYS" /FD /c
+# SUBTRACT CPP /YX
+# ADD BASE RSC /l 0x409 /d "NDEBUG"
+# ADD RSC /l 0x409 /d "NDEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /subsystem:console /machine:I386
+# ADD LINK32 Win32_DLL_Release\libpng13.lib ..\..\..\zlib\projects\visualc6\Win32_DLL_Release\zlib1.lib /nologo /subsystem:console /machine:I386
+# Begin Special Build Tool
+OutDir=.\Win32_DLL_Release
+SOURCE="$(InputPath)"
+PostBuild_Desc=[Run Test]
+PostBuild_Cmds=set path=$(outdir);..\..\..\zlib\projects\visualc6\Win32_DLL_Release;	$(outdir)\pngtest.exe ..\..\pngtest.png
+# End Special Build Tool
+
+!ELSEIF  "$(CFG)" == "pngtest - Win32 DLL Debug"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 1
+# PROP BASE Output_Dir "pngtest___Win32_DLL_Debug"
+# PROP BASE Intermediate_Dir "pngtest___Win32_DLL_Debug"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 1
+# PROP Output_Dir "Win32_DLL_Debug"
+# PROP Intermediate_Dir "Win32_DLL_Debug"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+# ADD BASE CPP /nologo /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c
+# SUBTRACT BASE CPP /YX
+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /I "..\..\..\zlib" /D "WIN32" /D "_DEBUG" /D "PNG_DLL" /D "PNG_NO_STDIO" /D "PNG_NO_GLOBAL_ARRAYS" /FD /GZ /c
+# SUBTRACT CPP /YX
+# ADD BASE RSC /l 0x409 /d "_DEBUG"
+# ADD RSC /l 0x409 /d "_DEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept
+# ADD LINK32 Win32_DLL_Debug\libpng13d.lib ..\..\..\zlib\projects\visualc6\Win32_DLL_Debug\zlib1d.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept
+# Begin Special Build Tool
+OutDir=.\Win32_DLL_Debug
+SOURCE="$(InputPath)"
+PostBuild_Desc=[Run Test]
+PostBuild_Cmds=set path=$(outdir);..\..\..\zlib\projects\visualc6\Win32_DLL_Debug;	$(outdir)\pngtest.exe ..\..\pngtest.png
+# End Special Build Tool
+
+!ELSEIF  "$(CFG)" == "pngtest - Win32 DLL ASM Release"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 0
+# PROP BASE Output_Dir "pngtest___Win32_DLL_ASM_Release"
+# PROP BASE Intermediate_Dir "pngtest___Win32_DLL_ASM_Release"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 0
+# PROP Output_Dir "Win32_DLL_ASM_Release"
+# PROP Intermediate_Dir "Win32_DLL_ASM_Release"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+# ADD BASE CPP /nologo /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT BASE CPP /YX
+# ADD CPP /nologo /MD /W3 /O2 /I "..\..\..\zlib" /D "WIN32" /D "NDEBUG" /D "PNG_DLL" /D "PNG_NO_STDIO" /D "PNG_NO_GLOBAL_ARRAYS" /FD /c
+# SUBTRACT CPP /YX
+# ADD BASE RSC /l 0x409 /d "NDEBUG"
+# ADD RSC /l 0x409 /d "NDEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /subsystem:console /machine:I386
+# ADD LINK32 Win32_DLL_ASM_Release\libpng13.lib ..\..\..\zlib\projects\visualc6\Win32_DLL_ASM_Release\zlib1.lib /nologo /subsystem:console /machine:I386
+# Begin Special Build Tool
+OutDir=.\Win32_DLL_ASM_Release
+SOURCE="$(InputPath)"
+PostBuild_Desc=[Run Test]
+PostBuild_Cmds=set path=$(outdir);..\..\..\zlib\projects\visualc6\Win32_DLL_ASM_Release;	$(outdir)\pngtest.exe ..\..\pngtest.png
+# End Special Build Tool
+
+!ELSEIF  "$(CFG)" == "pngtest - Win32 DLL ASM Debug"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 1
+# PROP BASE Output_Dir "pngtest___Win32_DLL_ASM_Debug"
+# PROP BASE Intermediate_Dir "pngtest___Win32_DLL_ASM_Debug"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 1
+# PROP Output_Dir "Win32_DLL_ASM_Debug"
+# PROP Intermediate_Dir "Win32_DLL_ASM_Debug"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+# ADD BASE CPP /nologo /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c
+# SUBTRACT BASE CPP /YX
+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /I "..\..\..\zlib" /D "WIN32" /D "_DEBUG" /D "PNG_DLL" /D "PNG_NO_STDIO" /D "PNG_NO_GLOBAL_ARRAYS" /FD /GZ /c
+# SUBTRACT CPP /YX
+# ADD BASE RSC /l 0x409 /d "_DEBUG"
+# ADD RSC /l 0x409 /d "_DEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept
+# ADD LINK32 Win32_DLL_ASM_Debug\libpng13d.lib ..\..\..\zlib\projects\visualc6\Win32_DLL_ASM_Debug\zlib1d.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept
+# Begin Special Build Tool
+OutDir=.\Win32_DLL_ASM_Debug
+SOURCE="$(InputPath)"
+PostBuild_Desc=[Run Test]
+PostBuild_Cmds=set path=$(outdir);..\..\..\zlib\projects\visualc6\Win32_DLL_ASM_Debug;	$(outdir)\pngtest.exe ..\..\pngtest.png
+# End Special Build Tool
+
+!ELSEIF  "$(CFG)" == "pngtest - Win32 LIB Release"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 0
+# PROP BASE Output_Dir "pngtest___Win32_LIB_Release"
+# PROP BASE Intermediate_Dir "pngtest___Win32_LIB_Release"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 0
+# PROP Output_Dir "Win32_LIB_Release"
+# PROP Intermediate_Dir "Win32_LIB_Release"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+# ADD BASE CPP /nologo /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT BASE CPP /YX
+# ADD CPP /nologo /MD /W3 /O2 /I "..\..\..\zlib" /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT CPP /YX
+# ADD BASE RSC /l 0x409 /d "NDEBUG"
+# ADD RSC /l 0x409 /d "NDEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /subsystem:console /machine:I386
+# ADD LINK32 Win32_LIB_Release\libpng.lib ..\..\..\zlib\projects\visualc6\Win32_LIB_Release\zlib.lib /nologo /subsystem:console /machine:I386
+# Begin Special Build Tool
+OutDir=.\Win32_LIB_Release
+SOURCE="$(InputPath)"
+PostBuild_Desc=[Run Test]
+PostBuild_Cmds=$(outdir)\pngtest.exe ..\..\pngtest.png
+# End Special Build Tool
+
+!ELSEIF  "$(CFG)" == "pngtest - Win32 LIB Debug"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 1
+# PROP BASE Output_Dir "pngtest___Win32_LIB_Debug"
+# PROP BASE Intermediate_Dir "pngtest___Win32_LIB_Debug"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 1
+# PROP Output_Dir "Win32_LIB_Debug"
+# PROP Intermediate_Dir "Win32_LIB_Debug"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+# ADD BASE CPP /nologo /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c
+# SUBTRACT BASE CPP /YX
+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /I "..\..\..\zlib" /D "WIN32" /D "_DEBUG" /FD /GZ /c
+# SUBTRACT CPP /YX
+# ADD BASE RSC /l 0x409 /d "_DEBUG"
+# ADD RSC /l 0x409 /d "_DEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept
+# ADD LINK32 Win32_LIB_Debug\libpngd.lib ..\..\..\zlib\projects\visualc6\Win32_LIB_Debug\zlibd.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept
+# Begin Special Build Tool
+OutDir=.\Win32_LIB_Debug
+SOURCE="$(InputPath)"
+PostBuild_Desc=[Run Test]
+PostBuild_Cmds=$(outdir)\pngtest.exe ..\..\pngtest.png
+# End Special Build Tool
+
+!ELSEIF  "$(CFG)" == "pngtest - Win32 LIB ASM Release"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 0
+# PROP BASE Output_Dir "pngtest___Win32_LIB_ASM_Release"
+# PROP BASE Intermediate_Dir "pngtest___Win32_LIB_ASM_Release"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 0
+# PROP Output_Dir "Win32_LIB_ASM_Release"
+# PROP Intermediate_Dir "Win32_LIB_ASM_Release"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+# ADD BASE CPP /nologo /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT BASE CPP /YX
+# ADD CPP /nologo /MD /W3 /O2 /I "..\..\..\zlib" /D "WIN32" /D "NDEBUG" /FD /c
+# SUBTRACT CPP /YX
+# ADD BASE RSC /l 0x409 /d "NDEBUG"
+# ADD RSC /l 0x409 /d "NDEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /subsystem:console /machine:I386
+# ADD LINK32 Win32_LIB_ASM_Release\libpng.lib ..\..\..\zlib\projects\visualc6\Win32_LIB_ASM_Release\zlib.lib /nologo /subsystem:console /machine:I386
+# Begin Special Build Tool
+OutDir=.\Win32_LIB_ASM_Release
+SOURCE="$(InputPath)"
+PostBuild_Desc=[Run Test]
+PostBuild_Cmds=$(outdir)\pngtest.exe ..\..\pngtest.png
+# End Special Build Tool
+
+!ELSEIF  "$(CFG)" == "pngtest - Win32 LIB ASM Debug"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 1
+# PROP BASE Output_Dir "pngtest___Win32_LIB_ASM_Debug"
+# PROP BASE Intermediate_Dir "pngtest___Win32_LIB_ASM_Debug"
+# PROP BASE Target_Dir ""
+# PROP Use_MFC 0
+# PROP Use_Debug_Libraries 1
+# PROP Output_Dir "Win32_LIB_ASM_Debug"
+# PROP Intermediate_Dir "Win32_LIB_ASM_Debug"
+# PROP Ignore_Export_Lib 0
+# PROP Target_Dir ""
+# ADD BASE CPP /nologo /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c
+# SUBTRACT BASE CPP /YX
+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /I "..\..\..\zlib" /D "WIN32" /D "_DEBUG" /FD /GZ /c
+# SUBTRACT CPP /YX
+# ADD BASE RSC /l 0x409 /d "_DEBUG"
+# ADD RSC /l 0x409 /d "_DEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
+# ADD BASE LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept
+# ADD LINK32 Win32_LIB_ASM_Debug\libpngd.lib ..\..\..\zlib\projects\visualc6\Win32_LIB_ASM_Debug\zlibd.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept
+# Begin Special Build Tool
+OutDir=.\Win32_LIB_ASM_Debug
+SOURCE="$(InputPath)"
+PostBuild_Desc=[Run Test]
+PostBuild_Cmds=$(outdir)\pngtest.exe ..\..\pngtest.png
+# End Special Build Tool
+
+!ENDIF 
+
+# Begin Target
+
+# Name "pngtest - Win32 DLL Release"
+# Name "pngtest - Win32 DLL Debug"
+# Name "pngtest - Win32 DLL ASM Release"
+# Name "pngtest - Win32 DLL ASM Debug"
+# Name "pngtest - Win32 LIB Release"
+# Name "pngtest - Win32 LIB Debug"
+# Name "pngtest - Win32 LIB ASM Release"
+# Name "pngtest - Win32 LIB ASM Debug"
+# Begin Group "Source Files"
+
+# PROP Default_Filter "cpp;c;cxx;rc;def;r;odl;idl;hpj;bat"
+# Begin Source File
+
+SOURCE=..\..\pngtest.c
+# End Source File
+# End Group
+# End Target
+# End Project
diff --git a/gs/libpng/projects/visualc71/PRJ0041.mak b/gs/libpng/projects/visualc71/PRJ0041.mak
new file mode 100644
index 000000000..3a597b023
--- /dev/null
+++ b/gs/libpng/projects/visualc71/PRJ0041.mak
@@ -0,0 +1,21 @@
+# Prevent "Cannot find missing dependency..." warnings while compiling
+# pngw32.rc (PRJ0041).
+
+all: $(IntDir)\alloc.h \
+	 $(IntDir)\fp.h \
+	 $(IntDir)\m68881.h \
+	 $(IntDir)\mem.h \
+	 $(IntDir)\pngusr.h \
+	 $(IntDir)\strings.h \
+	 $(IntDir)\unistd.h \
+	 $(IntDir)\unixio.h
+	 
+$(IntDir)\alloc.h \
+$(IntDir)\fp.h \
+$(IntDir)\m68881.h \
+$(IntDir)\mem.h \
+$(IntDir)\pngusr.h \
+$(IntDir)\strings.h \
+$(IntDir)\unistd.h \
+$(IntDir)\unixio.h:
+	@!echo.>$@
diff --git a/gs/libpng/projects/visualc71/README.txt b/gs/libpng/projects/visualc71/README.txt
new file mode 100644
index 000000000..7bd63327e
--- /dev/null
+++ b/gs/libpng/projects/visualc71/README.txt
@@ -0,0 +1,57 @@
+Microsoft Developer Studio Project File, Format Version 7.10 for libpng.
+
+Copyright (C) 2004 Simon-Pierre Cadieux.
+For conditions of distribution and use, see copyright notice in png.h
+
+Assumptions:
+* The libpng source files are in ..\..
+* The zlib source files are in ..\..\..\zlib
+* The zlib project file is in . /* Warning: This is until the zlib project
+  files get intergrated into the next zlib release. The final zlib project
+  directory will then be ..\..\..\zlib\projects\visualc71. */
+
+To use:
+
+1) On the main menu, select "File | Open Solution".
+   Open "libpng.sln".
+
+2) Display the Solution Explorer view (Ctrl+Alt+L)
+
+3) Set one of the project as the StartUp project. If you just want to build the
+   binaries set "libpng" as the startup project (Select "libpng" tree view
+   item + Project | Set as StartUp project). If you want to build and test the
+   binaries set it to "pngtest" (Select "pngtest" tree view item +
+   Project | Set as StartUp project)
+
+4) Select "Build | Configuration Manager...".
+   Choose the configuration you wish to build.
+
+5) Select "Build | Clean Solution".
+
+6) Select "Build | Build Solution (Ctrl-Shift-B)"
+
+This project builds the libpng binaries as follows:
+
+* Win32_DLL_Release\libpng13.dll      DLL build
+* Win32_DLL_Debug\libpng13d.dll       DLL build (debug version)
+* Win32_DLL_ASM_Release\libpng13.dll  DLL build using ASM code
+* Win32_DLL_ASM_Debug\libpng13d.dll   DLL build using ASM (debug version)
+* Win32_DLL_VB\libpng13vb.dll         DLL build for Visual Basic, using stdcall
+* Win32_LIB_Release\libpng.lib        static build
+* Win32_LIB_Debug\libpngd.lib         static build (debug version)
+* Win32_LIB_ASM_Release\libpng.lib    static build using ASM code
+* Win32_LIB_ASM_Debug\libpngd.lib     static build using ASM (debug version)
+
+Notes:
+
+If you change anything in the source files, or select different compiler
+settings, please change the DLL name to something different than any of
+the above names. Also, make sure that in your "pngusr.h" you define
+PNG_USER_PRIVATEBUILD and PNG_USER_DLLFNAME_POSTFIX according to the
+instructions provided in "pngconf.h".
+
+All DLLs built by this project use the Microsoft dynamic C runtime library
+MSVCR71.DLL (MSVCR71D.DLL for debug versions).  If you distribute any of the
+above mentioned libraries you may have to include this DLL in your package.
+For a list of files that are redistributable in Visual Studio see
+$(VCINSTALLDIR)\redist.txt.
diff --git a/gs/libpng/projects/visualc71/README_zlib.txt b/gs/libpng/projects/visualc71/README_zlib.txt
new file mode 100644
index 000000000..ff6a5c7cb
--- /dev/null
+++ b/gs/libpng/projects/visualc71/README_zlib.txt
@@ -0,0 +1,44 @@
+/* WARNING: This file was put in the LibPNG distribution for convenience only.
+            It is expected to be part of the next zlib release under
+            "projects\visualc71\README.txt." */
+
+Microsoft Developer Studio Project File, Format Version 7.10 for zlib.
+
+Copyright (C) 2004 Simon-Pierre Cadieux.
+Copyright (C) 2004 Cosmin Truta.
+For conditions of distribution and use, see copyright notice in zlib.h.
+
+
+To use:
+
+1) On the main menu, select "File | Open Solution".
+   Open "zlib.sln".
+
+2) Display the Solution Explorer view (Ctrl+Alt+L)
+
+3) Set one of the project as the StartUp project. If you just want to build the
+   binaries set "zlib" as the startup project (Select "zlib" tree view item +
+   Project | Set as StartUp project). If you want to build and test the
+   binaries set it to "example" (Select "example" tree view item + Project |
+   Set as StartUp project), If you want to build the minigzip utility set it to
+   "minigzip" (Select "minigzip" tree view item + Project | Set as StartUp
+   project
+
+4) Select "Build | Configuration Manager...".
+   Choose the configuration you wish to build.
+
+5) Select "Build | Clean Solution".
+
+6) Select "Build | Build Solution (Ctrl-Shift-B)"
+
+This project builds the zlib binaries as follows:
+
+* Win32_DLL_Release\zlib1.dll       DLL build
+* Win32_DLL_Debug\zlib1d.dll        DLL build (debug version)
+* Win32_DLL_ASM_Release\zlib1.dll   DLL build using ASM code
+* Win32_DLL_ASM_Debug\zlib1d.dll    DLL build using ASM code (debug version)
+* Win32_LIB_Release\zlib.lib        static build
+* Win32_LIB_Debug\zlibd.lib         static build (debug version)
+* Win32_LIB_ASM_Release\zlib.lib    static build using ASM code
+* Win32_LIB_ASM_Debug\zlibd.lib     static build using ASM code (debug version)
+
diff --git a/gs/libpng/projects/visualc71/libpng.sln b/gs/libpng/projects/visualc71/libpng.sln
new file mode 100644
index 000000000..d49277eb0
--- /dev/null
+++ b/gs/libpng/projects/visualc71/libpng.sln
@@ -0,0 +1,88 @@
+Microsoft Visual Studio Solution File, Format Version 8.00
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "libpng", "libpng.vcproj", "{0008960E-E0DD-41A6-8265-00B31DDB4C21}"
+	ProjectSection(ProjectDependencies) = postProject
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0} = {2D4F8105-7D21-454C-9932-B47CAB71A5C0}
+	EndProjectSection
+EndProject
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "pngtest", "pngtest.vcproj", "{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}"
+	ProjectSection(ProjectDependencies) = postProject
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21} = {0008960E-E0DD-41A6-8265-00B31DDB4C21}
+	EndProjectSection
+EndProject
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "zlib", "zlib.vcproj", "{2D4F8105-7D21-454C-9932-B47CAB71A5C0}"
+	ProjectSection(ProjectDependencies) = postProject
+	EndProjectSection
+EndProject
+Global
+	GlobalSection(SolutionConfiguration) = preSolution
+		DLL ASM Debug = DLL ASM Debug
+		DLL ASM Release = DLL ASM Release
+		DLL Debug = DLL Debug
+		DLL Release = DLL Release
+		DLL VB = DLL VB
+		LIB ASM Debug = LIB ASM Debug
+		LIB ASM Release = LIB ASM Release
+		LIB Debug = LIB Debug
+		LIB Release = LIB Release
+	EndGlobalSection
+	GlobalSection(ProjectConfiguration) = postSolution
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.DLL ASM Debug.ActiveCfg = DLL ASM Debug|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.DLL ASM Debug.Build.0 = DLL ASM Debug|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.DLL ASM Release.ActiveCfg = DLL ASM Release|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.DLL ASM Release.Build.0 = DLL ASM Release|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.DLL Debug.ActiveCfg = DLL Debug|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.DLL Debug.Build.0 = DLL Debug|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.DLL Release.ActiveCfg = DLL Release|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.DLL Release.Build.0 = DLL Release|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.DLL VB.ActiveCfg = DLL VB|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.DLL VB.Build.0 = DLL VB|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.LIB ASM Debug.ActiveCfg = LIB ASM Debug|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.LIB ASM Debug.Build.0 = LIB ASM Debug|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.LIB ASM Release.ActiveCfg = LIB ASM Release|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.LIB ASM Release.Build.0 = LIB ASM Release|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.LIB Debug.ActiveCfg = LIB Debug|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.LIB Debug.Build.0 = LIB Debug|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.LIB Release.ActiveCfg = LIB Release|Win32
+		{0008960E-E0DD-41A6-8265-00B31DDB4C21}.LIB Release.Build.0 = LIB Release|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.DLL ASM Debug.ActiveCfg = DLL ASM Debug|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.DLL ASM Debug.Build.0 = DLL ASM Debug|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.DLL ASM Release.ActiveCfg = DLL ASM Release|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.DLL ASM Release.Build.0 = DLL ASM Release|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.DLL Debug.ActiveCfg = DLL Debug|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.DLL Debug.Build.0 = DLL Debug|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.DLL Release.ActiveCfg = DLL Release|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.DLL Release.Build.0 = DLL Release|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.DLL VB.ActiveCfg = DLL VB|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.DLL VB.Build.0 = DLL VB|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.LIB ASM Debug.ActiveCfg = LIB ASM Debug|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.LIB ASM Debug.Build.0 = LIB ASM Debug|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.LIB ASM Release.ActiveCfg = LIB ASM Release|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.LIB ASM Release.Build.0 = LIB ASM Release|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.LIB Debug.ActiveCfg = LIB Debug|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.LIB Debug.Build.0 = LIB Debug|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.LIB Release.ActiveCfg = LIB Release|Win32
+		{FD1C2F86-9EEF-47BD-95A4-530917E17FDA}.LIB Release.Build.0 = LIB Release|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.DLL ASM Debug.ActiveCfg = DLL ASM Debug|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.DLL ASM Debug.Build.0 = DLL ASM Debug|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.DLL ASM Release.ActiveCfg = DLL ASM Release|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.DLL ASM Release.Build.0 = DLL ASM Release|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.DLL Debug.ActiveCfg = DLL Debug|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.DLL Debug.Build.0 = DLL Debug|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.DLL Release.ActiveCfg = DLL Release|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.DLL Release.Build.0 = DLL Release|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.DLL VB.ActiveCfg = DLL Release|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.DLL VB.Build.0 = DLL Release|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.LIB ASM Debug.ActiveCfg = LIB ASM Debug|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.LIB ASM Debug.Build.0 = LIB ASM Debug|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.LIB ASM Release.ActiveCfg = LIB ASM Release|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.LIB ASM Release.Build.0 = LIB ASM Release|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.LIB Debug.ActiveCfg = LIB Debug|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.LIB Debug.Build.0 = LIB Debug|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.LIB Release.ActiveCfg = LIB Release|Win32
+		{2D4F8105-7D21-454C-9932-B47CAB71A5C0}.LIB Release.Build.0 = LIB Release|Win32
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+	EndGlobalSection
+	GlobalSection(ExtensibilityAddIns) = postSolution
+	EndGlobalSection
+EndGlobal
diff --git a/gs/libpng/projects/visualc71/libpng.vcproj b/gs/libpng/projects/visualc71/libpng.vcproj
new file mode 100644
index 000000000..76e122a12
--- /dev/null
+++ b/gs/libpng/projects/visualc71/libpng.vcproj
@@ -0,0 +1,735 @@
+<?xml version="1.0" encoding="Windows-1252"?>
+<VisualStudioProject
+	ProjectType="Visual C++"
+	Version="7.10"
+	Name="libpng"
+	RootNamespace="libpng">
+	<Platforms>
+		<Platform
+			Name="Win32"/>
+	</Platforms>
+	<Configurations>
+		<Configuration
+			Name="DLL Release|Win32"
+			OutputDirectory=".\Win32_DLL_Release"
+			IntermediateDirectory=".\Win32_DLL_Release"
+			ConfigurationType="2">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG;PNG_BUILD_DLL;ZLIB_DLL"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				UsePrecompiledHeader="3"
+				PrecompiledHeaderThrough="png.h"
+				WarningLevel="3"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/libpng13.dll"
+				LinkIncremental="1"
+				ModuleDefinitionFile="..\..\scripts\pngw32.def"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"
+				PreprocessorDefinitions="NDEBUG"
+				Culture="1033"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib;$(IntDir)"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="DLL Debug|Win32"
+			OutputDirectory=".\Win32_DLL_Debug"
+			IntermediateDirectory=".\Win32_DLL_Debug"
+			ConfigurationType="2">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG;DEBUG;PNG_DEBUG=1;PNG_BUILD_DLL;ZLIB_DLL"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				UsePrecompiledHeader="3"
+				PrecompiledHeaderThrough="png.h"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/libpng13d.dll"
+				ModuleDefinitionFile="..\..\scripts\pngw32.def"
+				GenerateDebugInformation="TRUE"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"
+				PreprocessorDefinitions="_DEBUG,PNG_DEBUG=1"
+				Culture="1033"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib;$(IntDir)"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="DLL ASM Release|Win32"
+			OutputDirectory=".\Win32_DLL_ASM_Release"
+			IntermediateDirectory=".\Win32_DLL_ASM_Release"
+			ConfigurationType="2">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG;PNG_USE_PNGVCRD;PNG_BUILD_DLL;ZLIB_DLL;PNG_LIBPNG_SPECIALBUILD"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				UsePrecompiledHeader="3"
+				PrecompiledHeaderThrough="png.h"
+				WarningLevel="3"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/libpng13.dll"
+				LinkIncremental="1"
+				ModuleDefinitionFile="..\..\scripts\pngw32.def"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"
+				AdditionalOptions="/d PNG_LIBPNG_SPECIALBUILD=&quot;&quot;&quot;&quot;Use MMX instructions&quot;&quot;&quot;&quot;"
+				PreprocessorDefinitions="NDEBUG"
+				Culture="1033"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib;$(IntDir)"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="DLL ASM Debug|Win32"
+			OutputDirectory=".\Win32_DLL_ASM_Debug"
+			IntermediateDirectory=".\Win32_DLL_ASM_Debug"
+			ConfigurationType="2">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG;DEBUG;PNG_DEBUG=1;PNG_USE_PNGVCRD;PNG_BUILD_DLL;ZLIB_DLL;PNG_LIBPNG_SPECIALBUILD"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				UsePrecompiledHeader="3"
+				PrecompiledHeaderThrough="png.h"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/libpng13d.dll"
+				ModuleDefinitionFile="..\..\scripts\pngw32.def"
+				GenerateDebugInformation="TRUE"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"
+				AdditionalOptions="/d PNG_LIBPNG_SPECIALBUILD=&quot;&quot;&quot;&quot;Use MMX instructions&quot;&quot;&quot;&quot;"
+				PreprocessorDefinitions="_DEBUG,PNG_DEBUG=1"
+				Culture="1033"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib;$(IntDir)"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="DLL VB|Win32"
+			OutputDirectory=".\Win32_DLL_VB"
+			IntermediateDirectory=".\Win32_DLL_VB"
+			ConfigurationType="2">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG;PNG_BUILD_DLL;ZLIB_DLL;PNGAPI=__stdcall;PNG_NO_MODULEDEF;PNG_LIBPNG_SPECIALBUILD"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				UsePrecompiledHeader="3"
+				PrecompiledHeaderThrough="png.h"
+				WarningLevel="3"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/libpng13vb.dll"
+				LinkIncremental="1"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"
+				AdditionalOptions="/d PNG_LIBPNG_DLLFNAME_POSTFIX=&quot;&quot;&quot;&quot;VB&quot;&quot;&quot;&quot; /d PNG_LIBPNG_SPECIALBUILD=&quot;&quot;&quot;&quot;__stdcall calling convention used for exported functions&quot;&quot;&quot;&quot;"
+				PreprocessorDefinitions="NDEBUG"
+				Culture="1033"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib;$(IntDir)"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB Release|Win32"
+			OutputDirectory=".\Win32_LIB_Release"
+			IntermediateDirectory=".\Win32_LIB_Release"
+			ConfigurationType="4">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				UsePrecompiledHeader="3"
+				PrecompiledHeaderThrough="png.h"
+				WarningLevel="3"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLibrarianTool"
+				OutputFile="$(OutDir)/libpng.lib"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB Debug|Win32"
+			OutputDirectory=".\Win32_LIB_Debug"
+			IntermediateDirectory=".\Win32_LIB_Debug"
+			ConfigurationType="4">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..;..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG;DEBUG;PNG_DEBUG=1"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				UsePrecompiledHeader="3"
+				PrecompiledHeaderThrough="png.h"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLibrarianTool"
+				OutputFile="$(OutDir)/libpngd.lib"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB ASM Release|Win32"
+			OutputDirectory=".\Win32_LIB_ASM_Release"
+			IntermediateDirectory=".\Win32_LIB_ASM_Release"
+			ConfigurationType="4">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..,..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG;PNG_USE_PNGVCRD;PNG_LIBPNG_SPECIALBUILD"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				UsePrecompiledHeader="3"
+				PrecompiledHeaderThrough="png.h"
+				WarningLevel="3"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLibrarianTool"
+				OutputFile="$(OutDir)/libpng.lib"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB ASM Debug|Win32"
+			OutputDirectory=".\Win32_LIB_ASM_Debug"
+			IntermediateDirectory=".\Win32_LIB_ASM_Debug"
+			ConfigurationType="4">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..,..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG;DEBUG;PNG_DEBUG=1;PNG_USE_PNGVCRD;PNG_LIBPNG_SPECIALBUILD"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				UsePrecompiledHeader="3"
+				PrecompiledHeaderThrough="png.h"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLibrarianTool"
+				OutputFile="$(OutDir)/libpngd.lib"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+	</Configurations>
+	<References>
+	</References>
+	<Files>
+		<Filter
+			Name="Source Files"
+			Filter="cpp;c;cxx;rc;def;r;odl;idl;hpj;bat">
+			<File
+				RelativePath="..\..\png.c">
+				<FileConfiguration
+					Name="DLL Release|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="0"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL Debug|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="0"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL ASM Release|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="0"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL ASM Debug|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="0"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL VB|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="0"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Release|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="0"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Debug|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="0"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Release|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="0"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Debug|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="0"/>
+				</FileConfiguration>
+			</File>
+			<File
+				RelativePath="..\..\pngerror.c">
+				<FileConfiguration
+					Name="DLL Release|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="1"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL Debug|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="1"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL ASM Release|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="1"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL ASM Debug|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="1"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL VB|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="1"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Release|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="1"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Debug|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="1"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Release|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="1"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Debug|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						UsePrecompiledHeader="1"/>
+				</FileConfiguration>
+			</File>
+			<File
+				RelativePath="..\..\pngget.c">
+			</File>
+			<File
+				RelativePath="..\..\pngmem.c">
+			</File>
+			<File
+				RelativePath="..\..\pngpread.c">
+			</File>
+			<File
+				RelativePath="..\..\pngread.c">
+			</File>
+			<File
+				RelativePath="..\..\pngrio.c">
+			</File>
+			<File
+				RelativePath="..\..\pngrtran.c">
+			</File>
+			<File
+				RelativePath="..\..\pngrutil.c">
+			</File>
+			<File
+				RelativePath="..\..\pngset.c">
+			</File>
+			<File
+				RelativePath="..\..\pngtrans.c">
+			</File>
+			<File
+				RelativePath="..\..\pngvcrd.c">
+				<FileConfiguration
+					Name="DLL Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCLCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCLCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL VB|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCLCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCLCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCLCompilerTool"/>
+				</FileConfiguration>
+			</File>
+			<File
+				RelativePath="..\..\scripts\pngw32.def">
+				<FileConfiguration
+					Name="DLL VB|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+			</File>
+			<File
+				RelativePath="..\..\pngwio.c">
+			</File>
+			<File
+				RelativePath="..\..\pngwrite.c">
+			</File>
+			<File
+				RelativePath="..\..\pngwtran.c">
+			</File>
+			<File
+				RelativePath="..\..\pngwutil.c">
+			</File>
+		</Filter>
+		<Filter
+			Name="Header Files"
+			Filter="h;hpp;hxx;hm;inl">
+			<File
+				RelativePath="..\..\png.h">
+			</File>
+			<File
+				RelativePath="..\..\pngconf.h">
+			</File>
+		</Filter>
+		<Filter
+			Name="Resource Files"
+			Filter="ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe">
+			<File
+				RelativePath="..\..\scripts\pngw32.rc">
+				<FileConfiguration
+					Name="LIB Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCResourceCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCResourceCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCResourceCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCResourceCompilerTool"/>
+				</FileConfiguration>
+			</File>
+		</Filter>
+		<File
+			RelativePath=".\PRJ0041.mak">
+			<FileConfiguration
+				Name="DLL Release|Win32">
+				<Tool
+					Name="VCCustomBuildTool"
+					Description="Create dummy include files to prevent &quot;Cannot find missing dependency...&quot; warnings."
+					CommandLine="nmake -f PRJ0041.mak IntDir=$(IntDir)"
+					Outputs="$(IntDir)\alloc.h;$(IntDir)\fp.h;$(IntDir)\m68881.h;$(IntDir)\mem.h;$(IntDir)\pngusr.h;$(IntDir)\strings.h;$(IntDir)\unistd.h;$(IntDir)\unixio.h"/>
+			</FileConfiguration>
+			<FileConfiguration
+				Name="DLL Debug|Win32">
+				<Tool
+					Name="VCCustomBuildTool"
+					Description="Create dummy include files to prevent &quot;Cannot find missing dependency...&quot; warnings."
+					CommandLine="nmake -f PRJ0041.mak IntDir=$(IntDir)"
+					Outputs="$(IntDir)\alloc.h;$(IntDir)\fp.h;$(IntDir)\m68881.h;$(IntDir)\mem.h;$(IntDir)\pngusr.h;$(IntDir)\strings.h;$(IntDir)\unistd.h;$(IntDir)\unixio.h"/>
+			</FileConfiguration>
+			<FileConfiguration
+				Name="DLL ASM Release|Win32">
+				<Tool
+					Name="VCCustomBuildTool"
+					Description="Create dummy include files to prevent &quot;Cannot find missing dependency...&quot; warnings."
+					CommandLine="nmake -f PRJ0041.mak IntDir=$(IntDir)"
+					Outputs="$(IntDir)\alloc.h;$(IntDir)\fp.h;$(IntDir)\m68881.h;$(IntDir)\mem.h;$(IntDir)\pngusr.h;$(IntDir)\strings.h;$(IntDir)\unistd.h;$(IntDir)\unixio.h"/>
+			</FileConfiguration>
+			<FileConfiguration
+				Name="DLL ASM Debug|Win32">
+				<Tool
+					Name="VCCustomBuildTool"
+					Description="Create dummy include files to prevent &quot;Cannot find missing dependency...&quot; warnings."
+					CommandLine="nmake -f PRJ0041.mak IntDir=$(IntDir)"
+					Outputs="$(IntDir)\alloc.h;$(IntDir)\fp.h;$(IntDir)\m68881.h;$(IntDir)\mem.h;$(IntDir)\pngusr.h;$(IntDir)\strings.h;$(IntDir)\unistd.h;$(IntDir)\unixio.h"/>
+			</FileConfiguration>
+			<FileConfiguration
+				Name="DLL VB|Win32">
+				<Tool
+					Name="VCCustomBuildTool"
+					Description="Create dummy include files to prevent &quot;Cannot find missing dependency...&quot; warnings."
+					CommandLine="nmake -f PRJ0041.mak IntDir=$(IntDir)"
+					Outputs="$(IntDir)\alloc.h;$(IntDir)\fp.h;$(IntDir)\m68881.h;$(IntDir)\mem.h;$(IntDir)\pngusr.h;$(IntDir)\strings.h;$(IntDir)\unistd.h;$(IntDir)\unixio.h"/>
+			</FileConfiguration>
+		</File>
+		<File
+			RelativePath="README.txt">
+		</File>
+	</Files>
+	<Globals>
+	</Globals>
+</VisualStudioProject>
diff --git a/gs/libpng/projects/visualc71/pngtest.vcproj b/gs/libpng/projects/visualc71/pngtest.vcproj
new file mode 100644
index 000000000..e7a29277d
--- /dev/null
+++ b/gs/libpng/projects/visualc71/pngtest.vcproj
@@ -0,0 +1,459 @@
+<?xml version="1.0" encoding="Windows-1252"?>
+<VisualStudioProject
+	ProjectType="Visual C++"
+	Version="7.10"
+	Name="pngtest"
+	RootNamespace="pngtest">
+	<Platforms>
+		<Platform
+			Name="Win32"/>
+	</Platforms>
+	<Configurations>
+		<Configuration
+			Name="DLL Release|Win32"
+			OutputDirectory=".\Win32_DLL_Release\Test"
+			IntermediateDirectory=".\Win32_DLL_Release\Test"
+			ConfigurationType="1">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG;PNG_DLL;PNG_NO_STDIO;PNG_NO_GLOBAL_ARRAYS"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				WarningLevel="3"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"
+				Description="Testing..."
+				CommandLine="set path=$(OutDir)\..;$(OutDir)\..\ZLib
+$(TargetPath) ..\..\pngtest.png $(IntDir)\pngout.png"
+				Outputs="$(IntDir)\pngout.png"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/pngtest.exe"
+				LinkIncremental="1"
+				SubSystem="1"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="DLL Debug|Win32"
+			OutputDirectory=".\Win32_DLL_Debug\Test"
+			IntermediateDirectory=".\Win32_DLL_Debug\Test"
+			ConfigurationType="1">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG;PNG_DLL;PNG_NO_STDIO;PNG_NO_GLOBAL_ARRAYS"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"
+				Description="Testing..."
+				CommandLine="set path=$(OutDir)\..;$(OutDir)\..\ZLib
+$(TargetPath) ..\..\pngtest.png $(IntDir)\pngout.png"
+				Outputs="$(IntDir)\pngout.png"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/pngtest.exe"
+				GenerateDebugInformation="TRUE"
+				SubSystem="1"
+				TargetMachine="1"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="DLL ASM Release|Win32"
+			OutputDirectory=".\Win32_DLL_ASM_Release\Test"
+			IntermediateDirectory=".\Win32_DLL_ASM_Release\Test"
+			ConfigurationType="1">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG;PNG_DLL;PNG_NO_STDIO;PNG_NO_GLOBAL_ARRAYS"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				WarningLevel="3"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"
+				Description="Testing..."
+				CommandLine="set path=$(OutDir)\..;$(OutDir)\..\ZLib
+$(TargetPath) ..\..\pngtest.png $(IntDir)\pngout.png"
+				Outputs="$(IntDir)\pngout.png"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/pngtest.exe"
+				LinkIncremental="1"
+				SubSystem="1"
+				TargetMachine="1"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="DLL ASM Debug|Win32"
+			OutputDirectory=".\Win32_DLL_ASM_Debug\Test"
+			IntermediateDirectory=".\Win32_DLL_ASM_Debug\Test"
+			ConfigurationType="1">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG;PNG_DLL;PNG_NO_STDIO;PNG_NO_GLOBAL_ARRAYS"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"
+				Description="Testing..."
+				CommandLine="set path=$(OutDir)\..;$(OutDir)\..\ZLib
+$(TargetPath) ..\..\pngtest.png $(IntDir)\pngout.png"
+				Outputs="$(IntDir)\pngout.png"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/pngtest.exe"
+				GenerateDebugInformation="TRUE"
+				SubSystem="1"
+				TargetMachine="1"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="DLL VB|Win32"
+			OutputDirectory=".\Win32_DLL_VB\Test"
+			IntermediateDirectory=".\Win32_DLL_VB\Test"
+			ConfigurationType="1">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG;PNG_DLL;PNG_NO_STDIO;PNG_NO_GLOBAL_ARRAYS;PNGAPI=__stdcall"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				WarningLevel="2"
+				CallingConvention="2"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"
+				Description="Testing..."
+				CommandLine="set path=$(OutDir)\..;$(OutDir)\..\..\Win32_DLL_Release\ZLib
+$(TargetPath) ..\..\pngtest.png $(IntDir)\pngout.png"
+				Outputs="$(IntDir)\pngout.png"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/pngtest.exe"
+				LinkIncremental="1"
+				IgnoreDefaultLibraryNames="$(IntDir)\libpng13vb.lib"
+				SubSystem="1"
+				TargetMachine="1"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB Release|Win32"
+			OutputDirectory=".\Win32_LIB_Release\Test"
+			IntermediateDirectory=".\Win32_LIB_Release\Test"
+			ConfigurationType="1">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG;PNG_NO_GLOBAL_ARRAYS"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				WarningLevel="3"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"
+				Description="Testing..."
+				CommandLine="set path=$(OutDir)\..;$(OutDir)\..\ZLib
+$(TargetPath) ..\..\pngtest.png $(IntDir)\pngout.png"
+				Outputs="$(IntDir)\pngout.png"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/pngtest.exe"
+				LinkIncremental="1"
+				SubSystem="1"
+				TargetMachine="1"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB Debug|Win32"
+			OutputDirectory=".\Win32_LIB_Debug\Test"
+			IntermediateDirectory=".\Win32_LIB_Debug\Test"
+			ConfigurationType="1">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG;PNG_NO_GLOBAL_ARRAYS"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"
+				Description="Testing..."
+				CommandLine="set path=$(OutDir)\..;$(OutDir)\..\ZLib
+$(TargetPath) ..\..\pngtest.png $(IntDir)\pngout.png"
+				Outputs="$(IntDir)\pngout.png"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/pngtest.exe"
+				GenerateDebugInformation="TRUE"
+				SubSystem="1"
+				TargetMachine="1"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB ASM Release|Win32"
+			OutputDirectory=".\Win32_LIB_ASM_Release\Test"
+			IntermediateDirectory=".\Win32_LIB_ASM_Release\Test"
+			ConfigurationType="1">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG;PNG_NO_GLOBAL_ARRAYS"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				WarningLevel="3"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"
+				Description="Testing..."
+				CommandLine="set path=$(OutDir)\..;$(OutDir)\..\ZLib
+$(TargetPath) ..\..\pngtest.png $(IntDir)\pngout.png"
+				Outputs="$(IntDir)\pngout.png"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/pngtest.exe"
+				LinkIncremental="1"
+				SubSystem="1"
+				TargetMachine="1"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB ASM Debug|Win32"
+			OutputDirectory=".\Win32_LIB_ASM_Debug\Test"
+			IntermediateDirectory=".\Win32_LIB_ASM_Debug\Test"
+			ConfigurationType="1">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG;PNG_NO_GLOBAL_ARRAYS"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="0"/>
+			<Tool
+				Name="VCCustomBuildTool"
+				Description="Testing..."
+				CommandLine="set path=$(OutDir)\..;$(OutDir)\..\ZLib
+$(TargetPath) ..\..\pngtest.png $(IntDir)\pngout.png"
+				Outputs="$(IntDir)\pngout.png"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)/pngtest.exe"
+				GenerateDebugInformation="TRUE"
+				SubSystem="1"
+				TargetMachine="1"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+	</Configurations>
+	<References>
+	</References>
+	<Files>
+		<Filter
+			Name="Source Files"
+			Filter="cpp;c;cxx;rc;def;r;odl;idl;hpj;bat">
+			<File
+				RelativePath="..\..\pngtest.c">
+			</File>
+		</Filter>
+	</Files>
+	<Globals>
+	</Globals>
+</VisualStudioProject>
diff --git a/gs/libpng/projects/visualc71/zlib.vcproj b/gs/libpng/projects/visualc71/zlib.vcproj
new file mode 100644
index 000000000..5574ae38e
--- /dev/null
+++ b/gs/libpng/projects/visualc71/zlib.vcproj
@@ -0,0 +1,670 @@
+<?xml version="1.0" encoding="Windows-1252"?>
+<VisualStudioProject
+	ProjectType="Visual C++"
+	Version="7.10"
+	Name="zlib">
+	<Platforms>
+		<Platform
+			Name="Win32"/>
+	</Platforms>
+	<Configurations>
+		<Configuration
+			Name="DLL Release|Win32"
+			OutputDirectory=".\Win32_DLL_Release\ZLib"
+			IntermediateDirectory=".\Win32_DLL_Release\ZLib"
+			ConfigurationType="2">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				WarningLevel="3"
+				CompileAs="1"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)\zlib1.dll"
+				LinkIncremental="1"
+				ModuleDefinitionFile="..\..\..\zlib\win32\zlib.def"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"
+				PreprocessorDefinitions="NDEBUG"
+				Culture="1033"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="DLL Debug|Win32"
+			OutputDirectory=".\Win32_DLL_Debug\ZLib"
+			IntermediateDirectory=".\Win32_DLL_Debug\ZLib"
+			ConfigurationType="2">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="1"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)\zlib1d.dll"
+				ModuleDefinitionFile="..\..\..\zlib\win32\zlib.def"
+				GenerateDebugInformation="TRUE"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"
+				PreprocessorDefinitions="_DEBUG"
+				Culture="1033"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="DLL ASM Release|Win32"
+			OutputDirectory=".\Win32_DLL_ASM_Release\ZLib"
+			IntermediateDirectory=".\Win32_DLL_ASM_Release\ZLib"
+			ConfigurationType="2">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG;ASMV;ASMINF"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				WarningLevel="3"
+				CompileAs="1"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)\zlib1.dll"
+				LinkIncremental="1"
+				ModuleDefinitionFile="..\..\..\zlib\win32\zlib.def"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"
+				PreprocessorDefinitions="NDEBUG"
+				Culture="1033"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="DLL ASM Debug|Win32"
+			OutputDirectory=".\Win32_DLL_ASM_Debug\ZLib"
+			IntermediateDirectory=".\Win32_DLL_ASM_Debug\ZLib"
+			ConfigurationType="2">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG;ASMV;ASMINF"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="1"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLinkerTool"
+				OutputFile="$(OutDir)\zlib1d.dll"
+				ModuleDefinitionFile="..\..\..\zlib\win32\zlib.def"
+				GenerateDebugInformation="TRUE"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"
+				PreprocessorDefinitions="_DEBUG"
+				Culture="1033"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCWebDeploymentTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB Release|Win32"
+			OutputDirectory=".\Win32_LIB_Release\ZLib"
+			IntermediateDirectory=".\Win32_LIB_Release\ZLib"
+			ConfigurationType="4">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				WarningLevel="3"
+				CompileAs="1"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLibrarianTool"
+				OutputFile="$(OutDir)\zlib.lib"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB Debug|Win32"
+			OutputDirectory=".\Win32_LIB_Debug\ZLib"
+			IntermediateDirectory=".\Win32_LIB_Debug\ZLib"
+			ConfigurationType="4">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="1"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLibrarianTool"
+				OutputFile="$(OutDir)\zlibd.lib"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB ASM Release|Win32"
+			OutputDirectory=".\Win32_LIB_ASM_Release\ZLib"
+			IntermediateDirectory=".\Win32_LIB_ASM_Release\ZLib"
+			ConfigurationType="4">
+			<Tool
+				Name="VCCLCompilerTool"
+				InlineFunctionExpansion="1"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;NDEBUG;ASMV;ASMINF"
+				StringPooling="TRUE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="TRUE"
+				WarningLevel="3"
+				CompileAs="1"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLibrarianTool"
+				OutputFile="$(OutDir)\zlib.lib"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+		<Configuration
+			Name="LIB ASM Debug|Win32"
+			OutputDirectory=".\Win32_LIB_ASM_Debug\ZLib"
+			IntermediateDirectory=".\Win32_LIB_ASM_Debug\ZLib"
+			ConfigurationType="4">
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="..\..\..\zlib"
+				PreprocessorDefinitions="WIN32;_DEBUG;ASMV;ASMINF"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				WarningLevel="3"
+				DebugInformationFormat="4"
+				CompileAs="1"/>
+			<Tool
+				Name="VCCustomBuildTool"/>
+			<Tool
+				Name="VCLibrarianTool"
+				OutputFile="$(OutDir)\zlibd.lib"/>
+			<Tool
+				Name="VCMIDLTool"/>
+			<Tool
+				Name="VCPostBuildEventTool"/>
+			<Tool
+				Name="VCPreBuildEventTool"/>
+			<Tool
+				Name="VCPreLinkEventTool"/>
+			<Tool
+				Name="VCResourceCompilerTool"/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"/>
+			<Tool
+				Name="VCManagedWrapperGeneratorTool"/>
+			<Tool
+				Name="VCAuxiliaryManagedWrapperGeneratorTool"/>
+		</Configuration>
+	</Configurations>
+	<References>
+	</References>
+	<Files>
+		<Filter
+			Name="Source Files"
+			Filter="cpp;c;cxx;rc;def;r;odl;idl;hpj;bat">
+			<File
+				RelativePath="..\..\..\zlib\adler32.c">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\compress.c">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\crc32.c">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\deflate.c">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\gzio.c">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\infback.c">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\inffast.c">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\inflate.c">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\inftrees.c">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\trees.c">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\uncompr.c">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\win32\zlib.def">
+				<FileConfiguration
+					Name="LIB Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\zutil.c">
+			</File>
+		</Filter>
+		<Filter
+			Name="Header Files"
+			Filter="h;hpp;hxx;hm;inl">
+			<File
+				RelativePath="..\..\..\zlib\crc32.h">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\deflate.h">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\inffast.h">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\inffixed.h">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\inflate.h">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\inftrees.h">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\trees.h">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\zconf.h">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\zlib.h">
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\zutil.h">
+			</File>
+		</Filter>
+		<Filter
+			Name="Resource Files"
+			Filter="ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe">
+			<File
+				RelativePath="..\..\..\zlib\win32\zlib1.rc">
+				<FileConfiguration
+					Name="LIB Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCResourceCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCResourceCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCResourceCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCResourceCompilerTool"/>
+				</FileConfiguration>
+			</File>
+		</Filter>
+		<Filter
+			Name="Assembler Files (Unsupported)"
+			Filter="asm;obj;c;cpp;cxx;h;hpp;hxx">
+			<File
+				RelativePath="..\..\..\zlib\contrib\masmx86\gvmat32.asm">
+				<FileConfiguration
+					Name="DLL Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL ASM Release|Win32">
+					<Tool
+						Name="VCCustomBuildTool"
+						Description="Assembling..."
+						CommandLine="ml /nologo /c /Cx /coff /Fo&quot;$(IntDir)\$(InputName).obj&quot; &quot;$(InputPath)&quot;
+"
+						Outputs="$(IntDir)\$(InputName).obj"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL ASM Debug|Win32">
+					<Tool
+						Name="VCCustomBuildTool"
+						Description="Assembling..."
+						CommandLine="ml /nologo /c /Cx /coff /Zi /Fo&quot;$(IntDir)\$(InputName).obj&quot; &quot;$(InputPath)&quot;
+"
+						Outputs="$(IntDir)\$(InputName).obj"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Release|Win32">
+					<Tool
+						Name="VCCustomBuildTool"
+						Description="Assembling..."
+						CommandLine="ml /nologo /c /Cx /coff /Fo&quot;$(IntDir)\$(InputName).obj&quot; &quot;$(InputPath)&quot;
+"
+						Outputs="$(IntDir)\$(InputName).obj"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Debug|Win32">
+					<Tool
+						Name="VCCustomBuildTool"
+						Description="Assembling..."
+						CommandLine="ml /nologo /c /Cx /coff /Zi /Fo&quot;$(IntDir)\$(InputName).obj&quot; &quot;$(InputPath)&quot;
+"
+						Outputs="$(IntDir)\$(InputName).obj"/>
+				</FileConfiguration>
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\contrib\masmx86\gvmat32c.c">
+				<FileConfiguration
+					Name="DLL Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCLCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCLCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL ASM Release|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						AdditionalIncludeDirectories="..\.."/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL ASM Debug|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						AdditionalIncludeDirectories="..\.."/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCLCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCLCompilerTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Release|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						AdditionalIncludeDirectories="..\.."/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Debug|Win32">
+					<Tool
+						Name="VCCLCompilerTool"
+						AdditionalIncludeDirectories="..\.."/>
+				</FileConfiguration>
+			</File>
+			<File
+				RelativePath="..\..\..\zlib\contrib\masmx86\inffas32.asm">
+				<FileConfiguration
+					Name="DLL Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL ASM Release|Win32">
+					<Tool
+						Name="VCCustomBuildTool"
+						Description="Assembling..."
+						CommandLine="ml /nologo /c /Cx /coff /Fo&quot;$(IntDir)\$(InputName).obj&quot; &quot;$(InputPath)&quot;
+"
+						Outputs="$(IntDir)\$(InputName).obj"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="DLL ASM Debug|Win32">
+					<Tool
+						Name="VCCustomBuildTool"
+						Description="Assembling..."
+						CommandLine="ml /nologo /c /Cx /coff /Zi /Fo&quot;$(IntDir)\$(InputName).obj&quot; &quot;$(InputPath)&quot;
+"
+						Outputs="$(IntDir)\$(InputName).obj"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Release|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB Debug|Win32"
+					ExcludedFromBuild="TRUE">
+					<Tool
+						Name="VCCustomBuildTool"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Release|Win32">
+					<Tool
+						Name="VCCustomBuildTool"
+						Description="Assembling..."
+						CommandLine="ml /nologo /c /Cx /coff /Fo&quot;$(IntDir)\$(InputName).obj&quot; &quot;$(InputPath)&quot;
+"
+						Outputs="$(IntDir)\$(InputName).obj"/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="LIB ASM Debug|Win32">
+					<Tool
+						Name="VCCustomBuildTool"
+						Description="Assembling..."
+						CommandLine="ml /nologo /c /Cx /coff /Zi /Fo&quot;$(IntDir)\$(InputName).obj&quot; &quot;$(InputPath)&quot;
+"
+						Outputs="$(IntDir)\$(InputName).obj"/>
+				</FileConfiguration>
+			</File>
+		</Filter>
+		<File
+			RelativePath="README.txt">
+		</File>
+	</Files>
+	<Globals>
+	</Globals>
+</VisualStudioProject>
diff --git a/gs/libpng/projects/wince.txt b/gs/libpng/projects/wince.txt
new file mode 100644
index 000000000..a1a26c0bc
--- /dev/null
+++ b/gs/libpng/projects/wince.txt
@@ -0,0 +1,6 @@
+A set of project files is available for WinCE.  Get
+libpng-1.2.5-project-wince.zip from a libpng distribution
+site such as http://libpng.sourceforge.net
+
+Put the zip file in this directory (projects) and then run
+"unzip -a libpng-1.2.5-project-wince.zip"
diff --git a/gs/libpng/scripts/SCOPTIONS.ppc b/gs/libpng/scripts/SCOPTIONS.ppc
new file mode 100644
index 000000000..2c3503e9e
--- /dev/null
+++ b/gs/libpng/scripts/SCOPTIONS.ppc
@@ -0,0 +1,7 @@
+OPTIMIZE
+OPTPEEP
+OPTTIME
+OPTSCHED
+AUTOREGISTER
+PARMS=REGISTERS
+INCLUDEDIR=hlp:ppc/include
diff --git a/gs/libpng/scripts/descrip.mms b/gs/libpng/scripts/descrip.mms
new file mode 100644
index 000000000..3584b0d78
--- /dev/null
+++ b/gs/libpng/scripts/descrip.mms
@@ -0,0 +1,52 @@
+
+cc_defs = /inc=$(ZLIBSRC)
+c_deb = 
+
+.ifdef __DECC__
+pref = /prefix=all
+.endif
+
+
+
+OBJS = png.obj, pngset.obj, pngget.obj, pngrutil.obj, pngtrans.obj,\
+	pngwutil.obj, pngread.obj, pngmem.obj, pngwrite.obj, pngrtran.obj,\
+	pngwtran.obj, pngrio.obj, pngwio.obj, pngerror.obj, pngpread.obj
+
+
+CFLAGS= $(C_DEB) $(CC_DEFS) $(PREF)
+
+all : pngtest.exe libpng.olb
+		@ write sys$output " pngtest available"
+
+libpng.olb : libpng.olb($(OBJS))
+	@ write sys$output " Libpng available"
+
+
+pngtest.exe : pngtest.obj libpng.olb
+              link pngtest,libpng.olb/lib,$(ZLIBSRC)libz.olb/lib
+
+test : pngtest.exe
+   run pngtest
+
+clean :
+	delete *.obj;*,*.exe;*
+
+
+# Other dependencies.
+png.obj : png.h, pngconf.h
+pngpread.obj : png.h, pngconf.h
+pngset.obj : png.h, pngconf.h
+pngget.obj : png.h, pngconf.h
+pngread.obj : png.h, pngconf.h
+pngrtran.obj : png.h, pngconf.h
+pngrutil.obj : png.h, pngconf.h
+pngerror.obj : png.h, pngconf.h
+pngmem.obj : png.h, pngconf.h
+pngrio.obj : png.h, pngconf.h
+pngwio.obj : png.h, pngconf.h
+pngtest.obj : png.h, pngconf.h
+pngtrans.obj : png.h, pngconf.h
+pngwrite.obj : png.h, pngconf.h
+pngwtran.obj : png.h, pngconf.h
+pngwutil.obj : png.h, pngconf.h
+
diff --git a/gs/libpng/scripts/libpng-config-body.in b/gs/libpng/scripts/libpng-config-body.in
new file mode 100755
index 000000000..b466432d5
--- /dev/null
+++ b/gs/libpng/scripts/libpng-config-body.in
@@ -0,0 +1,96 @@
+
+usage()
+{
+    cat <<EOF
+Usage: libpng-config [OPTION] ...
+
+Known values for OPTION are:
+
+  --prefix        print libpng prefix
+  --libdir        print path to directory containing library
+  --libs          print library linking information
+  --ccopts        print compiler options
+  --cppflags      print pre-processor flags
+  --cflags        print preprocessor flags, I_opts, and compiler options
+  --I_opts        print "-I" include options
+  --L_opts        print linker "-L" flags for dynamic linking
+  --R_opts        print dynamic linker "-R" or "-rpath" flags
+  --ldopts        print linker options
+  --ldflags       print linker flags (ldopts, L_opts, R_opts, and libs)
+  --static        revise subsequent outputs for static linking
+  --help          print this help and exit
+  --version       print version information
+EOF
+
+    exit $1
+}
+
+if test $# -eq 0; then
+    usage 1
+fi
+
+while test $# -gt 0; do
+    case "$1" in
+
+    --prefix)
+        echo ${prefix}
+        ;;
+
+    --version)
+        echo ${version}
+        exit 0
+        ;;
+
+    --help)
+        usage 0
+        ;;
+
+    --ccopts)
+        echo ${ccopts}
+        ;;
+
+    --cppflags)
+        echo ${cppflags}
+        ;;
+
+    --cflags)
+        echo ${I_opts} ${cppflags} ${ccopts}
+        ;;
+
+    --libdir)
+        echo ${libdir}
+        ;;
+
+    --libs)
+        echo ${libs}
+        ;;
+
+    --I_opts)
+        echo ${I_opts}
+        ;;
+
+    --L_opts)
+        echo ${L_opts}
+        ;;
+
+    --R_opts)
+        echo ${R_opts}
+        ;;
+
+    --ldflags)
+        echo ${ldflags} ${L_opts} ${R_opts} ${libs}
+        ;;
+
+    --static)
+        R_opts=""
+        ;;
+
+    *)
+        usage
+        exit 1
+        ;;
+    esac
+    shift
+done
+
+exit 0
diff --git a/gs/libpng/scripts/libpng-config-head.in b/gs/libpng/scripts/libpng-config-head.in
new file mode 100755
index 000000000..b2c6a332e
--- /dev/null
+++ b/gs/libpng/scripts/libpng-config-head.in
@@ -0,0 +1,21 @@
+#! /bin/sh
+
+# libpng-config
+# provides configuration info for libpng.
+
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# For conditions of distribution and use, see copyright notice in png.h
+
+# Modeled after libxml-config.
+
+version=1.2.8
+prefix=""
+libdir=""
+libs=""
+I_opts=""
+L_opts=""
+R_opts=""
+cppflags=""
+ccopts=""
+ldopts=""
+
diff --git a/gs/libpng/scripts/libpng.icc b/gs/libpng/scripts/libpng.icc
new file mode 100644
index 000000000..f9c51af3a
--- /dev/null
+++ b/gs/libpng/scripts/libpng.icc
@@ -0,0 +1,44 @@
+// Project file for libpng (static)
+// IBM VisualAge/C++ version 4.0 or later
+// Copyright (C) 2000 Cosmin Truta
+// For conditions of distribution and use, see copyright notice in png.h
+// Notes:
+//   All modules are compiled in C mode
+//   Tested with IBM VAC++ 4.0 under Win32
+//   Expected to work with IBM VAC++ 4.0 or later under OS/2 and Win32
+//   Can be easily adapted for IBM VAC++ 4.0 or later under AIX
+// For conditions of distribution and use, see copyright notice in png.h
+
+option incl(searchpath, "../zlib"), opt(level, "2"),
+ link(libsearchpath, "../zlib")
+{
+   target type(lib) "libpng.lib"
+   {
+      source type(c) "png.c"
+      source type(c) "pngerror.c"
+      source type(c) "pngget.c"
+      source type(c) "pngmem.c"
+      source type(c) "pngpread.c"
+      source type(c) "pngread.c"
+      source type(c) "pngrio.c"
+      source type(c) "pngrtran.c"
+      source type(c) "pngrutil.c"
+      source type(c) "pngset.c"
+      source type(c) "pngtrans.c"
+      source type(c) "pngwio.c"
+      source type(c) "pngwrite.c"
+      source type(c) "pngwtran.c"
+      source type(c) "pngwutil.c"
+   }
+}
+
+option incl(searchpath, "../zlib"), opt(level, "2"),
+ link(libsearchpath, "../zlib")
+{
+   target type(exe) "pngtest.exe"
+   {
+      source type(c) "pngtest.c"
+      source type(lib) "libpng.lib"
+      source type(lib) "zlib.lib"
+   }
+}
diff --git a/gs/libpng/scripts/libpng.pc.in b/gs/libpng/scripts/libpng.pc.in
new file mode 100644
index 000000000..f164c4137
--- /dev/null
+++ b/gs/libpng/scripts/libpng.pc.in
@@ -0,0 +1,11 @@
+
+prefix=@PREFIX@
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${exec_prefix}/include
+
+Name: libpng12
+Description: Loads and saves PNG files
+Version: 1.2.8
+Libs: -L${libdir} -lpng12 -lz -lm
+Cflags: -I${includedir}/libpng12
diff --git a/gs/libpng/scripts/makefile.32sunu b/gs/libpng/scripts/makefile.32sunu
new file mode 100644
index 000000000..a70c1a1ab
--- /dev/null
+++ b/gs/libpng/scripts/makefile.32sunu
@@ -0,0 +1,235 @@
+# makefile for libpng on Solaris 2.x with cc
+# Contributed by William L. Sebok, based on makefile.linux
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# Copyright (C) 1998 Greg Roelofs
+# Copyright (C) 1996, 1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+CC=cc
+SUN_CC_FLAGS=-fast -xtarget=ultra
+SUN_LD_FLAGS=-fast -xtarget=ultra
+
+# where make install puts libpng.a, libpng12.so and libpng12/png.h
+prefix=/a
+
+# Where the zlib library and include files are located
+# Changing these to ../zlib poses a security risk.  If you want
+# to have zlib in an adjacent directory, specify the full path instead of "..".
+#ZLIBLIB=../zlib
+#ZLIBINC=../zlib
+
+ZLIBLIB=/usr/lib
+ZLIBINC=/usr/include
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+CFLAGS=-I$(ZLIBINC) $(SUN_CC_FLAGS) \
+	# $(WARNMORE) -g -DPNG_DEBUG=5
+LDFLAGS=$(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB) libpng.a -lz -lm
+
+#RANLIB=ranlib
+RANLIB=echo
+
+LIBNAME=libpng12
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -KPIC -o $@ $*.c
+
+all: libpng.a $(LIBNAME).so pngtest libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo libdir=\"$(LIBPATH)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo R_opts=\"-R$(LIBPATH)\"; \
+	echo ccopts=\"-xtarget=ultra\"; \
+	echo ldopts=\"-xtarget=ultra\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -f -s $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJSDLL)
+	@case "`type ld`" in *ucb*) \
+	echo; \
+	echo '## WARNING:'; \
+	echo '## The commands "CC" and "LD" must NOT refer to /usr/ucb/cc'; \
+	echo '## and /usr/ucb/ld.  If they do, you need to adjust your PATH'; \
+	echo '## environment variable to put /usr/ccs/bin ahead of /usr/ucb.'; \
+	echo '## The environment variable LD_LIBRARY_PATH should not be set'; \
+	echo '## at all.  If it is, things are likely to break because of'; \
+	echo '## the libucb dependency that is created.'; \
+	echo; \
+	;; \
+	esac
+	$(LD) -G -L$(ZLIBLIB) -R$(ZLIBLIB) -h $(LIBNAME).so.$(PNGMAJ) \
+	 -o $(LIBNAME).so.$(PNGVER) $(OBJSDLL)
+
+libpng.so.3.$(PNGMIN): $(OBJS)
+	$(LD) -G -L$(ZLIBLIB) -R$(ZLIBLIB) -h libpng.so.3 \
+	 -o libpng.so.3.$(PNGMIN)  $(OBJSDLL)
+
+pngtest: pngtest.o $(LIBNAME).so
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm $(DI)/libpng
+	(cd $(DI); ln -f -s $(LIBNAME) libpng; ln -f -s $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -f -s $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGVER)* $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGVER)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -f -s libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -f -s libpng.so.3 libpng.so; \
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ); \
+	ln -f -s $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/libpng12.pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/libpng12.pc
+	chmod 644 $(DL)/pkgconfig/libpng12.pc
+	(cd $(DL)/pkgconfig; ln -f -s libpng12.pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/libpng12-config
+	cp libpng-config $(DB)/libpng12-config
+	chmod 755 $(DB)/libpng12-config
+	(cd $(DB); ln -f -s libpng12-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) $(SUN_CC_FLAGS) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -o pngtestd -L$(DL) -R$(DL) `$(BINPATH)/libpng12-config --ldflags` \
+	   $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB)
+	./pngtestd pngtest.png
+
+test-installed:
+	echo
+	echo Testing installed dynamic shared library.
+	$(CC) $(SUN_CC_FLAGS) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags` \
+	   $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB)
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngtesti pngout.png \
+	libpng-config $(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* \
+	libpng.so.3.$(PNGMIN) \
+	libpng.pc
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.64sunu b/gs/libpng/scripts/makefile.64sunu
new file mode 100644
index 000000000..4b3360ad3
--- /dev/null
+++ b/gs/libpng/scripts/makefile.64sunu
@@ -0,0 +1,236 @@
+# makefile for libpng on Solaris 2.x with cc
+# Contributed by William L. Sebok, based on makefile.linux
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# Copyright (C) 1998 Greg Roelofs
+# Copyright (C) 1996, 1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+CC=cc
+SUN_CC_FLAGS=-fast -xtarget=ultra -xarch=v9
+SUN_LD_FLAGS=-fast -xtarget=ultra -xarch=v9
+
+# where make install puts libpng.a, libpng12.so and libpng12/png.h
+prefix=/a
+
+# Where the zlib library and include files are located
+# Changing these to ../zlib poses a security risk.  If you want
+# to have zlib in an adjacent directory, specify the full path instead of "..".
+#ZLIBLIB=../zlib
+#ZLIBINC=../zlib
+
+ZLIBLIB=/usr/lib
+ZLIBINC=/usr/include
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+CFLAGS=-I$(ZLIBINC) $(SUN_CC_FLAGS) \
+	# $(WARNMORE) -g -DPNG_DEBUG=5
+LDFLAGS=-L. -R. $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng12 -lz -lm
+
+#RANLIB=ranlib
+RANLIB=echo
+
+LIBNAME=libpng12
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -KPIC -o $@ $*.c
+
+all: libpng.a $(LIBNAME).so pngtest libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo libdir=\"$(LIBPATH)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo R_opts=\"-R$(LIBPATH)\"; \
+	echo ccopts=\"-xtarget=ultra -xarch=v9\"; \
+	echo ldopts=\"-xtarget=ultra -xarch=v9\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -f -s $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJSDLL)
+	@case "`type ld`" in *ucb*) \
+	echo; \
+	echo '## WARNING:'; \
+	echo '## The commands "CC" and "LD" must NOT refer to /usr/ucb/cc'; \
+	echo '## and /usr/ucb/ld.  If they do, you need to adjust your PATH'; \
+	echo '## environment variable to put /usr/ccs/bin ahead of /usr/ucb.'; \
+	echo '## The environment variable LD_LIBRARY_PATH should not be set'; \
+	echo '## at all.  If it is, things are likely to break because of'; \
+	echo '## the libucb dependency that is created.'; \
+	echo; \
+	;; \
+	esac
+	$(LD) -G -L$(ZLIBLIB) -R$(ZLIBLIB) -h $(LIBNAME).so.$(PNGMAJ) \
+	 -o $(LIBNAME).so.$(PNGVER) $(OBJSDLL)
+
+libpng.so.3.$(PNGMIN): $(OBJSDLL)
+	$(LD) -G -L$(ZLIBLIB) -R$(ZLIBLIB) -h libpng.so.3 \
+	 -o libpng.so.3.$(PNGMIN)  $(OBJSDLL)
+
+pngtest: pngtest.o $(LIBNAME).so
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm $(DI)/libpng
+	(cd $(DI); ln -f -s $(LIBNAME) libpng; ln -f -s $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -f -s $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ).$(PNGVER)*
+	-@/bin/rm -f $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGVER)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -f -s libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -f -s libpng.so.3 libpng.so; \
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ); \
+	ln -f -s $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -f -s $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -f -s $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) $(SUN_CC_FLAGS) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -o pngtestd -L$(DL) -R$(DL) `$(BINPATH)/libpng12-config --ldflags` \
+	   $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB)
+	./pngtestd pngtest.png
+
+test-installed:
+	echo
+	echo Testing installed dynamic shared library.
+	$(CC) $(SUN_CC_FLAGS) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags ` \
+	   $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB)
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngtesti pngout.png \
+	libpng-config $(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* \
+	libpng.so.3.$(PNGMIN) \
+	libpng.pc
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.acorn b/gs/libpng/scripts/makefile.acorn
new file mode 100644
index 000000000..470cf89b1
--- /dev/null
+++ b/gs/libpng/scripts/makefile.acorn
@@ -0,0 +1,51 @@
+# Project:   libpng
+
+
+# Toolflags:
+CCflags = -c -depend !Depend -IC:,Zlib: -g -throwback  -DRISCOS  -fnah
+C++flags = -c -depend !Depend -IC: -throwback
+Linkflags = -aif -c++ -o $@
+ObjAsmflags = -throwback -NoCache -depend !Depend
+CMHGflags = 
+LibFileflags = -c -l -o $@
+Squeezeflags = -o $@
+
+
+# Final targets:
+@.libpng-lib:   @.o.png @.o.pngerror @.o.pngrio @.o.pngwio @.o.pngmem \
+	@.o.pngpread @.o.pngset @.o.pngget @.o.pngread @.o.pngrtran \
+	@.o.pngrutil @.o.pngtrans @.o.pngwrite @.o.pngwtran @.o.pngwutil
+	LibFile $(LibFileflags) @.o.png @.o.pngerror @.o.pngrio @.o.pngrtran \
+	@.o.pngmem @.o.pngpread @.o.pngset @.o.pngget @.o.pngread @.o.pngwio \
+	@.o.pngrutil @.o.pngtrans  @.o.pngwrite @.o.pngwtran @.o.pngwutil
+@.mm-libpng-lib:   @.mm.png @.mm.pngerror @.mm.pngrio @.mm.pngwio @.mm.pngmem \
+	@.mm.pngpread @.mm.pngset @.mm.pngget @.mm.pngread @.mm.pngrtran \
+	@.mm.pngrutil @.mm.pngtrans @.mm.pngwrite @.mm.pngwtran @.mm.pngwutil
+	LibFile $(LibFileflags) @.mm.png @.mm.pngerror @.mm.pngrio \
+	@.mm.pngwio @.mm.pngmem @.mm.pngpread @.mm.pngset @.mm.pngget \
+	@.mm.pngread @.mm.pngrtran @.mm.pngrutil @.mm.pngtrans @.mm.pngwrite \
+	@.mm.pngwtran @.mm.pngwutil
+
+
+# User-editable dependencies:
+# (C) Copyright 1997 Tom Tanner
+Test: @.pngtest
+	<Prefix$Dir>.pngtest
+	@remove <Prefix$Dir>.pngtest
+
+#It would be nice if you could stop "make" listing from here on!
+@.pngtest:   @.o.pngtest @.libpng-lib C:o.Stubs Zlib:zlib_lib
+	Link $(Linkflags) @.o.pngtest @.libpng-lib C:o.Stubs Zlib:zlib_lib
+
+.SUFFIXES: .o .mm .c
+
+.c.mm:
+	MemCheck.CC cc $(ccflags) -o $@ LibPng:$<
+.c.o:
+	cc $(ccflags) -o $@ $<
+
+
+# Static dependencies:
+
+
+# Dynamic dependencies:
diff --git a/gs/libpng/scripts/makefile.aix b/gs/libpng/scripts/makefile.aix
new file mode 100644
index 000000000..93aec12b6
--- /dev/null
+++ b/gs/libpng/scripts/makefile.aix
@@ -0,0 +1,111 @@
+# makefile for libpng using gcc (generic, static library)
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# Copyright (C) 2000 Cosmin Truta
+# Copyright (C) 2000 Marc O. Gloor (AIX support added, from makefile.gcc)
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# Location of the zlib library and include files
+ZLIBINC = ../zlib
+ZLIBLIB = ../zlib
+
+# Compiler, linker, lib and other tools
+CC = gcc
+LD = $(CC)
+AR = ar rcs
+RANLIB = ranlib
+RM = rm -f
+
+LIBNAME=libpng12
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+prefix=/usr/local
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+
+CDEBUG = -g -DPNG_DEBUG=5
+LDDEBUG =
+CRELEASE = -O2
+LDRELEASE = -s
+WARNMORE=-Wall
+CFLAGS = -I$(ZLIBINC) $(WARNMORE) $(CRELEASE)
+LDFLAGS = -L. -L$(ZLIBLIB) -lpng12 -lz -lm $(LDRELEASE)
+
+# File extensions
+O=.o
+A=.a
+E=
+
+# Variables
+OBJS = png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O) \
+	pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O) \
+	pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
+
+# Targets
+all: $(LIBNAME)$(A) pngtest$(E)
+
+$(LIBNAME)$(A): $(OBJS)
+	$(AR) $@ $(OBJS)
+	$(RANLIB) $@
+
+test: pngtest$(E)
+	./pngtest$(E)
+
+pngtest$(E): pngtest$(O) $(LIBNAME)$(A)
+	$(LD) -o $@ pngtest$(O) $(LDFLAGS)
+
+install: $(LIBNAME)$(A)
+	-@if [ ! -d $(DI)  ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME)  ]; then mkdir $(DI)/$(LIBNAME); fi
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@rm -f $(DI)/$(LIBNAME)/png.h
+	-@rm -f $(DI)/$(LIBNAME)/pngconf.h
+	-@rm -f $(DI)/png.h
+	-@rm -f $(DI)/pngconf.h
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h \
+	$(DI)/$(LIBNAME)/pngconf.h
+	-@rm -rf $(DI)/libpng
+	(cd $(DI); ln -f -s $(LIBNAME) libpng; ln -f -s $(LIBNAME)/* .)
+	-@rm -f $(DL)/$(LIBNAME)$(A)
+	-@rm -f $(DL)/libpng$(A)
+	cp $(LIBNAME)$(A) $(DL)/$(LIBNAME)$(A)
+	chmod 644 $(DL)/$(LIBNAME)$(A)
+	(cd $(DL); ln -f -s $(LIBNAME)$(A) libpng$(A))
+	(cd $(DI); ln -f -s libpng/* .;)
+
+clean:
+	/bin/rm -f *.o $(LIBNAME)$(A) pngtest pngout.png
+
+png$(O): png.h pngconf.h
+pngerror$(O): png.h pngconf.h
+pngget$(O): png.h pngconf.h
+pngmem$(O): png.h pngconf.h
+pngpread$(O): png.h pngconf.h
+pngread$(O): png.h pngconf.h
+pngrio$(O): png.h pngconf.h
+pngrtran$(O): png.h pngconf.h
+pngrutil$(O): png.h pngconf.h
+pngset$(O): png.h pngconf.h
+pngtest$(O): png.h pngconf.h
+pngtrans$(O): png.h pngconf.h
+pngwio$(O): png.h pngconf.h
+pngwrite$(O): png.h pngconf.h
+pngwtran$(O): png.h pngconf.h
+pngwutil$(O): png.h pngconf.h
+
diff --git a/gs/libpng/scripts/makefile.amiga b/gs/libpng/scripts/makefile.amiga
new file mode 100644
index 000000000..79cb42499
--- /dev/null
+++ b/gs/libpng/scripts/makefile.amiga
@@ -0,0 +1,48 @@
+# Commodore Amiga Makefile
+# makefile for libpng and SAS C V6.5x compiler
+# Copyright (C) 1995-2000 Wolf Faust
+# For conditions of distribution and use, see copyright notice in png.h
+#
+# Note: Use #define PNG_READ_BIG_ENDIAN_SUPPORTED in pngconf.h
+#
+# Location/path of zlib include files
+ZLIB=/zlib
+#compiler
+CC=sc
+#compiler flags
+# WARNING: a bug in V6.51 causes bad code with OPTGO
+#          So use V6.55 or set NOOPTGO!!!!!!!!!
+CFLAGS= NOSTKCHK PARMS=REG OPTIMIZE OPTGO OPTPEEP OPTINLOCAL OPTINL\
+	OPTLOOP OPTRDEP=4 OPTDEP=4 OPTCOMP=4 INCLUDEDIR=$(ZLIB) \
+	DEFINE=PNG_INTERNAL
+#linker flags
+LDFLAGS= SD ND BATCH
+#link libs
+LDLIBS= libpng.lib libgz.lib LIB:scm.lib LIB:sc.lib Lib:amiga.lib
+# linker
+LN= slink
+# file deletion command
+RM= delete quiet
+# library (.lib) file creation command
+AR= oml
+# make directory command
+MKDIR= makedir
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+all: libpng.lib pngtest
+
+libpng.lib: $(OBJS)
+-$(RM) libpng.lib
+$(AR) libpng.lib r $(OBJS)
+
+pngtest: pngtest.o libpng.lib
+$(LN) <WITH <
+$(LDFLAGS)
+TO pngtest
+FROM LIB:c.o pngtest.o
+LIB $(LDLIBS)
+<
+
diff --git a/gs/libpng/scripts/makefile.atari b/gs/libpng/scripts/makefile.atari
new file mode 100644
index 000000000..9566d5d60
--- /dev/null
+++ b/gs/libpng/scripts/makefile.atari
@@ -0,0 +1,51 @@
+# makefile for libpng
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+# modified for LC56/ATARI assumes libz.lib is in same dir and uses default
+# rules for library management
+#
+CFLAGS=-I..\zlib -O
+LBR = png.lib
+LDFLAGS=-lpng -lz -lm
+
+# where make install puts libpng.a and png.h
+prefix=/usr/local
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+OBJS = $(LBR)(png.o) $(LBR)(pngset.o) $(LBR)(pngget.o) $(LBR)(pngrutil.o)\
+	$(LBR)(pngtrans.o) $(LBR)(pngwutil.o)\
+	$(LBR)(pngread.o) $(LBR)(pngerror.o) $(LBR)(pngwrite.o)\
+	$(LBR)(pngrtran.o) $(LBR)(pngwtran.o)\
+	$(LBR)(pngmem.o) $(LBR)(pngrio.o) $(LBR)(pngwio.o) $(LBR)(pngpread.o)
+
+all: $(LBR) pngtest.ttp
+
+$(LBR): $(OBJS)
+
+pngtest.ttp: pngtest.o $(LBR)
+	$(CC) $(CFLAGS) $(LDFLAGS) -o$@ pngtest.o
+
+install: libpng.a
+	-@mkdir $(DESTDIR)$(INCPATH)
+	-@mkdir $(DESTDIR)$(INCPATH)/libpng
+	-@mkdir $(DESTDIR)$(LIBPATH)
+	-@rm -f $(DESTDIR)$(INCPATH)/png.h
+	-@rm -f $(DESTDIR)$(INCPATH)/pngconf.h
+	cp png.h $(DESTDIR)$(INCPATH)/libpng
+	cp pngconf.h $(DESTDIR)$(INCPATH)/libpng
+	chmod 644 $(DESTDIR)$(INCPATH)/libpng/png.h
+	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pngconf.h
+	(cd $(DESTDIR)$(INCPATH); ln -f -s $(LIBNAME) libpng; \
+	ln -f -s $(LIBNAME)/* .)
diff --git a/gs/libpng/scripts/makefile.bc32 b/gs/libpng/scripts/makefile.bc32
new file mode 100644
index 000000000..90b178bc7
--- /dev/null
+++ b/gs/libpng/scripts/makefile.bc32
@@ -0,0 +1,151 @@
+# Makefile for libpng
+# 32-bit Borland C++ (Note: All modules are compiled in C mode)
+# To build the library, do:
+#       "make -fmakefile.bc32"
+#
+# -------------------- 32-bit Borland C++ --------------------
+
+### Absolutely necessary for this makefile to work
+.AUTODEPEND
+
+## Where zlib.h, zconf.h and zlib.lib are
+ZLIB_DIR=..\zlib
+
+
+## Compiler, linker and lib stuff
+CC=bcc32
+LD=bcc32
+LIB=tlib
+
+#TARGET_CPU=6
+# 3 = 386, 4 = 486, 5 = Pentium etc.
+!ifndef TARGET_CPU
+TARGET_CPU=5
+!endif
+
+# Use this if you don't want Borland's fancy exception handling
+NOEHLIB=noeh32.lib
+
+!ifdef DEBUG
+CDEBUG=-v
+LDEBUG=-v
+!else
+CDEBUG=
+LDEBUG=
+!endif
+
+# STACKOFLOW=1
+!ifdef STACKOFLOW
+CDEBUG=$(CDEBUG) -N
+LDEBUG=$(LDEBUG) -N
+!endif
+
+# -X- turn on dependency generation in the object file
+# -w  set all warnings on
+# -O2 optimize for speed
+# -Z  global optimization
+CFLAGS=-O2 -Z -X- -w -I$(ZLIB_DIR) -$(TARGET_CPU) $(CDEBUG)
+
+# -M  generate map file
+LDFLAGS=-M -L$(ZLIB_DIR) $(LDEBUG)
+
+
+## Variables
+OBJS = \
+	png.obj \
+	pngerror.obj \
+	pngget.obj \
+	pngmem.obj \
+	pngpread.obj \
+	pngread.obj \
+	pngrio.obj \
+	pngrtran.obj \
+	pngrutil.obj \
+	pngset.obj \
+	pngtrans.obj \
+	pngwio.obj \
+	pngwrite.obj \
+	pngwtran.obj \
+	pngwutil.obj
+
+LIBOBJS = \
+	+png.obj \
+	+pngerror.obj \
+	+pngget.obj \
+	+pngmem.obj \
+	+pngpread.obj \
+	+pngread.obj \
+	+pngrio.obj \
+	+pngrtran.obj \
+	+pngrutil.obj \
+	+pngset.obj \
+	+pngtrans.obj \
+	+pngwio.obj \
+	+pngwrite.obj \
+	+pngwtran.obj \
+	+pngwutil.obj
+
+LIBNAME=libpng.lib
+
+
+## Implicit rules
+# Braces let make "batch" calls to the compiler,
+# 2 calls instead of 12; space is important.
+.c.obj:
+	$(CC) $(CFLAGS) -c {$*.c }
+
+.c.exe:
+	$(CC) $(CFLAGS) $(LDFLAGS) $*.c $(LIBNAME) zlib.lib $(NOEHLIB)
+
+.obj.exe:
+	$(LD) $(LDFLAGS) $*.obj $(LIBNAME) zlib.lib $(NOEHLIB)
+
+
+## Major targets
+all: libpng pngtest
+
+libpng: $(LIBNAME)
+
+pngtest: pngtest.exe
+
+test: pngtest.exe
+	pngtest
+
+
+## Minor Targets
+
+png.obj: png.c
+pngerror.obj: pngerror.c
+pngget.obj: pngget.c
+pngmem.obj: pngmem.c
+pngpread.obj: pngpread.c
+pngread.obj: pngread.c
+pngrio.obj: pngrio.c
+pngrtran.obj: pngrtran.c
+pngrutil.obj: pngrutil.c
+pngset.obj: pngset.c
+pngtrans.obj: pngtrans.c
+pngwio.obj: pngwio.c
+pngwrite.obj: pngwrite.c
+pngwtran.obj: pngwtran.c
+pngwutil.obj: pngwutil.c
+
+
+$(LIBNAME): $(OBJS)
+	-del $(LIBNAME)
+	$(LIB) $(LIBNAME) @&&|
+$(LIBOBJS), libpng
+|
+
+
+# Clean up anything else you want
+clean:
+	-del *.obj
+	-del *.exe
+	-del *.lib
+	-del *.lst
+	-del *.map
+	-del *.tds
+
+
+# End of makefile for libpng
diff --git a/gs/libpng/scripts/makefile.beos b/gs/libpng/scripts/makefile.beos
new file mode 100644
index 000000000..98ace87c5
--- /dev/null
+++ b/gs/libpng/scripts/makefile.beos
@@ -0,0 +1,210 @@
+# makefile for libpng on BeOS x86 ELF with gcc
+# modified from makefile.linux by Sander Stoks
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# Copyright (C) 1999 Greg Roelofs
+# Copyright (C) 1996, 1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+CC=gcc
+
+# Where the zlib library and include files are located
+ZLIBLIB=/usr/local/lib
+ZLIBINC=/usr/local/include
+
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+ALIGN=
+# For i386:
+# ALIGN=-malign-loops=2 -malign-functions=2
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+
+# On BeOS, -O1 is actually better than -O3.  This is a known bug but it's
+# still here in R4.5
+CFLAGS=-I$(ZLIBINC) -Wall -O1 -funroll-loops \
+	$(ALIGN) # $(WARNMORE) -g -DPNG_DEBUG=5
+# LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng -lz -lm
+LDFLAGS=-L. -Wl,-soname=$(LIBNAME).so.$(PNGMAJ) -L$(ZLIBLIB) -lz -lm
+
+RANLIB=ranlib
+#RANLIB=echo
+
+# where make install puts libpng.a, libpng12.so*, and png.h
+prefix=/usr/local
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+LIBNAME=libpng12
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS)
+
+.SUFFIXES:      .c .o
+
+all: libpng.a $(LIBNAME).so pngtest libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+	cp $(LIBNAME).so* /boot/home/config/lib
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJSDLL)
+	$(CC) -nostart -Wl,-soname,$(LIBNAME).so.$(PNGMAJ) -o \
+	$(LIBNAME).so.$(PNGVER) $(OBJSDLL)
+
+libpng.so.3.$(PNGMIN): $(OBJSDLL)
+	$(CC) -nostart -Wl,-soname,libpng.so.3 -o \
+	libpng.so.3.$(PNGMIN) $(OBJSDLL)
+
+pngtest: pngtest.o $(LIBNAME).so
+	$(CC) -L$(ZLIBLIB) -lz -lpng12 -o pngtest pngtest.o
+
+test: pngtest
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -sf $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGVER)* $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGMIN)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -sf libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -sf libpng.so.3 libpng.so; \
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ); \
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) $(CFLAGS) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) -W1,-rpath $(ZLIBLIB):$(DL) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	$(CC) $(CFLAGS) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngout.png libpng-config \
+	$(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* pngtesti \
+	libpng.so.3.$(PNGMIN) \
+	libpng.pc
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.bor b/gs/libpng/scripts/makefile.bor
new file mode 100644
index 000000000..a5651aa3f
--- /dev/null
+++ b/gs/libpng/scripts/makefile.bor
@@ -0,0 +1,162 @@
+# Makefile for libpng
+# 16-bit Borland C++ (Note: All modules are compiled in C mode)
+# To build the library, do:
+#       "make -fmakefile.bor -DMODEL=c"
+# or:   "make -fmakefile.bor -DMODEL=l"
+#
+# ------------ Borland C++ ------------
+
+### Absolutely necessary for this makefile to work
+.AUTODEPEND
+
+## Where zlib.h, zconf.h and zlib_MODEL.lib are
+ZLIB_DIR=..\zlib
+
+
+## Compiler, linker and lib stuff
+CC=bcc
+LD=bcc
+LIB=tlib
+
+!ifndef MODEL
+MODEL=l
+!endif
+
+MODEL_ARG=-m$(MODEL)
+
+#TARGET_CPU=3
+# 2 = 286, 3 = 386, etc.
+!ifndef TARGET_CPU
+TARGET_CPU=2
+!endif
+
+# Use this if you don't want Borland's fancy exception handling
+# (for Borland C++ 4.0 or later)
+#NOEHLIB=noeh$(MODEL).lib
+
+!ifdef DEBUG
+CDEBUG=-v
+LDEBUG=-v
+!else
+CDEBUG=
+LDEBUG=
+!endif
+
+# STACKOFLOW=1
+!ifdef STACKOFLOW
+CDEBUG=$(CDEBUG) -N
+LDEBUG=$(LDEBUG) -N
+!endif
+
+# -X- turn on dependency generation in the object file
+# -w  set all warnings on
+# -O2 optimize for speed
+# -Z  global optimization
+CFLAGS=-O2 -Z -X- -w -I$(ZLIB_DIR) -$(TARGET_CPU) $(MODEL_ARG) $(CDEBUG)
+
+# -M  generate map file
+LDFLAGS=-M -L$(ZLIB_DIR) $(MODEL_ARG) $(LDEBUG)
+
+
+## Variables
+OBJS = \
+	png.obj \
+	pngerror.obj \
+	pngget.obj \
+	pngmem.obj \
+	pngpread.obj \
+	pngread.obj \
+	pngrio.obj \
+	pngrtran.obj \
+	pngrutil.obj \
+	pngset.obj \
+	pngtrans.obj \
+	pngwio.obj \
+	pngwrite.obj \
+	pngwtran.obj \
+	pngwutil.obj
+
+LIBOBJS = \
+	+png.obj \
+	+pngerror.obj \
+	+pngget.obj \
+	+pngmem.obj \
+	+pngpread.obj \
+	+pngread.obj \
+	+pngrio.obj \
+	+pngrtran.obj \
+	+pngrutil.obj \
+	+pngset.obj \
+	+pngtrans.obj \
+	+pngwio.obj \
+	+pngwrite.obj \
+	+pngwtran.obj \
+	+pngwutil.obj
+
+LIBNAME=libpng$(MODEL).lib
+
+
+## Implicit rules
+# Braces let make "batch" calls to the compiler,
+# 2 calls instead of 12; space is important.
+.c.obj:
+	$(CC) $(CFLAGS) -c {$*.c }
+
+.c.exe:
+	$(CC) $(CFLAGS) $(LDFLAGS) $*.c $(LIBNAME) zlib_$(MODEL).lib $(NOEHLIB)
+
+
+## Major targets
+all: libpng pngtest
+
+libpng: $(LIBNAME)
+
+pngtest: pngtest$(MODEL).exe
+
+test: pngtest$(MODEL).exe
+	pngtest$(MODEL)
+
+
+## Minor Targets
+
+png.obj: png.c
+pngerror.obj: pngerror.c
+pngget.obj: pngget.c
+pngmem.obj: pngmem.c
+pngpread.obj: pngpread.c
+pngread.obj: pngread.c
+pngrio.obj: pngrio.c
+pngrtran.obj: pngrtran.c
+pngrutil.obj: pngrutil.c
+pngset.obj: pngset.c
+pngtrans.obj: pngtrans.c
+pngwio.obj: pngwio.c
+pngwrite.obj: pngwrite.c
+pngwtran.obj: pngwtran.c
+pngwutil.obj: pngwutil.c
+
+
+$(LIBNAME): $(OBJS)
+	-del $(LIBNAME)
+	$(LIB) $(LIBNAME) @&&|
+$(LIBOBJS), libpng$(MODEL)
+|
+
+
+pngtest$(MODEL).obj: pngtest.c
+	$(CC) $(CFLAGS) -opngtest$(MODEL) -c pngtest.c
+
+pngtest$(MODEL).exe: pngtest$(MODEL).obj
+	$(LD) $(LDFLAGS) pngtest$(MODEL).obj $(LIBNAME) zlib_$(MODEL).lib $(NOEHLIB)
+
+
+# Clean up anything else you want
+clean:
+	-del *.obj
+	-del *.exe
+	-del *.lib
+	-del *.lst
+	-del *.map
+
+
+# End of makefile for libpng
diff --git a/gs/libpng/scripts/makefile.cygwin b/gs/libpng/scripts/makefile.cygwin
new file mode 100644
index 000000000..09f92d3ea
--- /dev/null
+++ b/gs/libpng/scripts/makefile.cygwin
@@ -0,0 +1,315 @@
+# makefile for cygwin on x86
+#   Builds both dll (with import lib) and static lib versions
+#   of the library, and builds two copies of pngtest: one
+#   statically linked and one dynamically linked.
+#
+# Copyright (C) 2002 Soren Anderson, Charles Wilson, and Glenn Randers-Pehrson
+#   based on makefile for linux-elf w/mmx by:
+# Copyright (C) 1998-2000 Greg Roelofs
+# Copyright (C) 1996, 1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+# This makefile intends to support building outside the src directory
+# if desired. When invoking it, specify an argument to SRCDIR on the
+# command line that points to the top of the directory where your source
+# is located.
+
+ifdef SRCDIR
+VPATH = $(SRCDIR)
+else
+SRCDIR = .
+endif
+
+# Override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+
+DESTDIR=
+
+# To enable assembler optimizations, add '-DPNG_USE_PNGGCCRD' to
+# $CFLAGS, and include pnggccrd.o in $OBJS, below, and in the dependency
+# list at the bottom of this makefile.
+
+CC=gcc
+ifdef MINGW
+MINGW_CCFLAGS=-mno-cygwin -I/usr/include/mingw
+MINGW_LDFLAGS=-mno-cygwin -L/usr/lib/mingw
+endif
+
+# Where "make install" puts libpng*.a, *png*.dll, png.h, and pngconf.h
+ifndef prefix
+prefix=/usr
+$(warning You haven't specified a 'prefix=' location. Defaulting to "/usr")
+endif
+
+# Where the zlib library and include files are located
+ZLIBLIB= /usr/lib
+ZLIBINC=
+#ZLIBLIB=../zlib
+#ZLIBINC=../zlib
+
+ALIGN=
+# for i386:
+#ALIGN=-malign-loops=2 -malign-functions=2
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+
+### if you use the asm, add pnggccrd.o to the OBJS list
+###
+### if you don't need thread safety, but want the asm accel
+#CFLAGS= $(strip $(MINGW_CCFLAGS) -DPNG_THREAD_UNSAFE_OK -DPNG_USE_PNGGCCRD \
+#	$(addprefix -I,$(ZLIBINC)) -Wall -O3 $(ALIGN) -funroll-loops \
+#	-fomit-frame-pointer)  # $(WARNMORE) -g -DPNG_DEBUG=5
+### if you need thread safety and want (minimal) asm accel
+#CFLAGS= $(strip $(MINGW_CCFLAGS) -DPNG_USE_PNGGCCRD $(addprefix -I,$(ZLIBINC)) \
+#	-Wall -O3 $(ALIGN) -funroll-loops \
+#	-fomit-frame-pointer)  # $(WARNMORE) -g -DPNG_DEBUG=5
+### Normal (non-asm) compilation
+CFLAGS= $(strip $(MINGW_CCFLAGS) $(addprefix -I,$(ZLIBINC)) \
+        -Wall -O3 $(ALIGN) -funroll-loops \
+	-fomit-frame-pointer) # $(WARNMORE) -g -DPNG_DEBUG=5
+
+LIBNAME = libpng12
+PNGMAJ = 0
+CYGDLL = 12
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+SHAREDLIB=cygpng$(CYGDLL).dll
+STATLIB=libpng.a
+IMPLIB=libpng.dll.a
+SHAREDDEF=libpng.def
+LIBS=$(SHAREDLIB) $(STATLIB)
+EXE=.exe
+
+LDFLAGS=$(strip -L. $(MINGW_LDFLAGS) -lpng $(addprefix -L,$(ZLIBLIB)) -lz)
+LDSFLAGS=$(strip -shared -L.  $(MINGW_LDFLAGS) -Wl,--export-all)
+LDEXTRA=-Wl,--out-implib=$(IMPLIB) $(addprefix -L,$(ZLIBLIB)) -lz
+
+MKDIR=/bin/mkdir -pv
+RANLIB=ranlib
+#RANLIB=echo
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+BINPATH=$(prefix)/bin
+MANPATH=$(prefix)/man
+MAN3PATH=$(MANPATH)/man3
+MAN5PATH=$(MANPATH)/man5
+
+# cosmetic: shortened strings:
+S =$(SRCDIR)
+D =$(DESTDIR)
+DB =$(D)$(BINPATH)
+DI =$(D)$(INCPATH)
+DL =$(D)$(LIBPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o # pnggccrd.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES: .c .o .pic.o
+
+%.o : %.c
+	$(CC) -c $(CFLAGS) -o $@ $<
+%.pic.o : CFLAGS += -DPNG_BUILD_DLL
+%.pic.o : %.c
+	$(CC) -c $(CFLAGS) -o $@ $<
+
+all: all-static all-shared libpng.pc libpng-config libpng.pc libpng-config
+
+# Make this to verify that "make [...] install" will do what you want.
+buildsetup-tell:
+	@echo  VPATH is set to: \"$(VPATH)\"
+	@echo  prefix is set to: \"$(prefix)\"
+	@echo -e INCPATH,LIBPATH, etc. are set to:'\n' \
+ $(addprefix $(D),$(INCPATH)'\n' $(LIBPATH)'\n' $(BINPATH)'\n' \
+   $(MANPATH)'\n' $(MAN3PATH)'\n' $(MAN5PATH)'\n')'\n'
+
+libpng.pc: scripts/libpng.pc.in
+	@echo -e Making pkg-config file for this libpng installation..'\n' \
+           using PREFIX=\"$(prefix)\"'\n'
+	cat $(S)/scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! | \
+	   sed -e s/-lm// > libpng.pc
+
+libpng-config: scripts/libpng-config-head.in scripts/libpng-config-body.in
+	@echo -e Making $(LIBNAME) libpng-config file for this libpng \
+ installation..'\n' using PREFIX=\"$(prefix)\"'\n'
+	( cat $(S)/scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo libs=\"-lpng$(CYGDLL) -lz\"; \
+	cat $(S)/scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+static: all-static
+shared: all-shared
+all-static: $(STATLIB) pngtest-stat$(EXE)
+all-shared: $(SHAREDLIB) pngtest$(EXE)
+
+pnggccrd.o: pnggccrd.c png.h pngconf.h
+	@echo ""
+	@echo '    You can ignore the "control reaches end of non-void function"'
+	@echo '    warning and "<variable> defined but not used" warnings:'
+	@echo ""
+	$(CC) -c $(CFLAGS) -o $@ $<
+
+pnggccrd.pic.o:	pnggccrd.c png.h pngconf.h
+	@echo ""
+	@echo '    You can ignore the "control reaches end of non-void function"'
+	@echo '    warning and "<variable> defined but not used" warnings:'
+	@echo ""
+	$(CC) -c $(CFLAGS) -DPNG_BUILD_DLL -o $@ $<
+
+$(STATLIB): $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+$(SHAREDDEF): scripts/png32ms.def
+	cat $< | sed -e '1{G;s/^\(.*\)\(\n\)/EXPORTS/;};2,/^EXPORTS/d' | \
+	sed -e 's/\([^;]*\);/;/' > $@
+
+$(SHAREDLIB): $(OBJSDLL) $(SHAREDDEF)
+	$(CC) $(LDSFLAGS) -o $@ $(OBJSDLL) -L. $(LDEXTRA)
+
+pngtest$(EXE): pngtest.pic.o $(SHAREDLIB)
+	$(CC) $(CFLAGS) $< $(LDFLAGS) -o $@
+
+pngtest-stat$(EXE): pngtest.o $(STATLIB)
+	$(CC) -static $(CFLAGS) $< $(LDFLAGS) -o $@
+
+pngtest.pic.o: pngtest.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+pngtest.o: pngtest.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+test: test-static test-shared
+
+test-static: pngtest-stat$(EXE)
+	./pngtest-stat $(S)/pngtest.png
+
+test-shared: pngtest$(EXE)
+	./pngtest $(S)/pngtest.png
+
+install-static: $(STATLIB) install-headers install-man
+	-@if [ ! -d $(DL) ]; then $(MKDIR) $(DL); fi
+	install -m 644 $(STATLIB) $(DL)/$(LIBNAME).a
+	-@rm -f $(DL)/$(STATLIB)
+	(cd $(DL); ln -sf $(LIBNAME).a $(STATLIB))
+
+install-shared: $(SHAREDLIB) libpng.pc libpng-config install-headers install-man
+	-@if [ ! -d $(DL) ]; then $(MKDIR) $(DL); fi
+	-@if [ ! -d $(DB) ]; then $(MKDIR) $(DB); fi
+	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR) $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	install -m 644 $(IMPLIB) $(DL)/$(LIBNAME).dll.a
+	-@rm -f $(DL)/$(IMPLIB)
+	(cd $(DL); ln -sf $(LIBNAME).dll.a $(IMPLIB))
+	install -s -m 755 $(SHAREDLIB) $(DB)
+	install -m 644 libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-headers:
+	-@if [ ! -d $(DI) ]; then $(MKDIR) $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR) $(DI)/$(LIBNAME); fi
+	-@rm -f $(DI)/png.h
+	-@rm -f $(DI)/pngconf.h
+	install -m 644 $(S)/png.h $(S)/pngconf.h $(DI)/$(LIBNAME)
+	-@rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-man:
+	-@if [ ! -d $(D)$(MAN3PATH) ]; then $(MKDIR) $(D)$(MAN3PATH); fi
+	-@if [ ! -d $(D)$(MAN5PATH) ]; then $(MKDIR) $(D)$(MAN5PATH); fi
+	install -m 644 $(S)/libpngpf.3 $(S)/libpng.3 $(D)$(MAN3PATH)
+	install -m 644 $(S)/png.5 $(D)$(MAN5PATH)
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+# Run this to verify that a future `configure' run will pick up the settings
+# you want.
+test-config-install: SHELL=/bin/bash
+test-config-install: $(DB)/libpng-config
+	@echo -e Testing libpng-config functions...'\n'
+	@ for TYRA in LDFLAGS CPPFLAGS CFLAGS LIBS VERSION; \
+   do \
+    printf "(%d)\t %10s =%s\n" $$(($$gytiu + 1)) $$TYRA \
+    "$$($(DB)/libpng-config `echo --$$TYRA |tr '[:upper:]' '[:lower:]'`)"; \
+    gytiu=$$(( $$gytiu + 1 )); \
+   done
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) $(CFLAGS) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	$(CC) $(CFLAGS) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) \
+	   -o pngtesti$(EXE) `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti$(EXE) pngtest.png
+
+clean:
+	/bin/rm -f *.pic.o *.o $(STATLIB) $(IMPLIB) $(SHAREDLIB) \
+	pngtest-stat$(EXE) pngtest$(EXE) pngout.png $(SHAREDDEF) \
+	libpng-config libpng.pc pngtesti$(EXE)
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+.PHONY: buildsetup-tell libpng.pc libpng-config test-config-install clean
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o:		png.h pngconf.h png.c
+pngerror.o pngerror.pic.o:	png.h pngconf.h pngerror.c
+pngrio.o pngrio.pic.o:		png.h pngconf.h pngrio.c
+pngwio.o pngwio.pic.o:		png.h pngconf.h pngwio.c
+pngmem.o pngmem.pic.o:		png.h pngconf.h pngmem.c
+pngset.o pngset.pic.o:		png.h pngconf.h pngset.c
+pngget.o pngget.pic.o:		png.h pngconf.h pngget.c
+pngread.o pngread.pic.o:	png.h pngconf.h pngread.c
+pngrtran.o pngrtran.pic.o:	png.h pngconf.h pngrtran.c
+pngrutil.o pngrutil.pic.o:	png.h pngconf.h pngrutil.c
+pngtrans.o pngtrans.pic.o:	png.h pngconf.h pngtrans.c
+pngwrite.o pngwrite.pic.o:	png.h pngconf.h pngwrite.c
+pngwtran.o pngwtran.pic.o:	png.h pngconf.h pngwtran.c
+pngwutil.o pngwutil.pic.o:	png.h pngconf.h pngwutil.c
+pngpread.o pngpread.pic.o:	png.h pngconf.h pngpread.c
+
+pngtest.o:			png.h pngconf.h pngtest.c
+pngtest-stat.o:			png.h pngconf.h pngtest.c
+
+
+
diff --git a/gs/libpng/scripts/makefile.darwin b/gs/libpng/scripts/makefile.darwin
new file mode 100644
index 000000000..1a1f988d2
--- /dev/null
+++ b/gs/libpng/scripts/makefile.darwin
@@ -0,0 +1,216 @@
+# makefile for libpng on Darwin / Mac OS X
+# Copyright (C) 2002,2004 Glenn Randers-Pehrson
+# Copyright (C) 2001 Christoph Pfisterer
+# derived from makefile.linux:
+#  Copyright (C) 1998, 1999 Greg Roelofs
+#  Copyright (C) 1996, 1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+# where "make install" puts libpng.a, libpng12.dylib, png.h and pngconf.h
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+CC=cc
+CFLAGS=-I$(ZLIBINC) -Wall -O3 -funroll-loops
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng12 -lz
+
+#RANLIB=echo
+RANLIB=ranlib
+
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+LIBNAME = libpng12
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -fno-common -o $@ $*.c
+
+all: libpng.a $(LIBNAME).dylib pngtest libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! | \
+	   sed -e s/-lm// > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).dylib: $(LIBNAME).$(PNGMAJ).dylib
+	ln -sf $(LIBNAME).$(PNGMAJ).dylib $(LIBNAME).dylib
+
+$(LIBNAME).$(PNGMAJ).dylib: $(LIBNAME).$(PNGVER).dylib
+	ln -sf $(LIBNAME).$(PNGVER).dylib $(LIBNAME).$(PNGMAJ).dylib
+
+$(LIBNAME).$(PNGVER).dylib: $(OBJSDLL)
+	$(CC) -dynamiclib \
+	 -install_name $(LIBPATH)/$(LIBNAME).$(PNGMAJ).dylib \
+	 -current_version $(PNGVER) -compatibility_version $(PNGVER) \
+	 -o $(LIBNAME).$(PNGVER).dylib \
+	 $(OBJSDLL) -L$(ZLIBLIB) -lz
+
+libpng.3.$(PNGMIN).dylib: $(OBJSDLL)
+	$(CC) -dynamiclib \
+	 -install_name $(LIBPATH)/libpng.3.dylib \
+	 -current_version 3 -compatibility_version 3 \
+	 -o libpng.3.$(PNGMIN).dylib \
+	 $(OBJSDLL) -L$(ZLIBLIB) -lz
+
+pngtest: pngtest.o $(LIBNAME).dylib
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	$(RANLIB) $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -sf $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).dylib libpng.pc \
+	libpng.3.$(PNGMIN).dylib
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).$(PNGVER)*.dylib
+	-@/bin/rm -f $(DL)/$(LIBNAME).$(PNGMAJ)*.dylib
+	-@/bin/rm -f $(DL)/$(LIBNAME).dylib
+	-@/bin/rm -f $(DL)/libpng.dylib
+	-@/bin/rm -f $(DL)/libpng.3.dylib
+	-@/bin/rm -f $(DL)/libpng.3.$(PNGMIN)*.dylib
+	cp $(LIBNAME).$(PNGVER).dylib $(DL)
+	cp libpng.3.$(PNGMIN).dylib $(DL)
+	chmod 755 $(DL)/$(LIBNAME).$(PNGVER).dylib
+	chmod 755 $(DL)/libpng.3.$(PNGMIN).dylib
+	(cd $(DL); \
+	ln -sf libpng.3.$(PNGMIN).dylib libpng.3.dylib; \
+	ln -sf libpng.3.dylib libpng.dylib; \
+	ln -sf $(LIBNAME).$(PNGVER).dylib $(LIBNAME).$(PNGMAJ).dylib; \
+	ln -sf $(LIBNAME).$(PNGMAJ).dylib $(LIBNAME).dylib)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	$(CC) $(CFLAGS) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	rm -f *.o libpng.a pngtest pngout.png libpng-config \
+	libpng.3.$(PNGMIN).dylib \
+	libpng.pc $(LIBNAME).*dylib pngtesti
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.dec b/gs/libpng/scripts/makefile.dec
new file mode 100644
index 000000000..f8482f98f
--- /dev/null
+++ b/gs/libpng/scripts/makefile.dec
@@ -0,0 +1,196 @@
+# makefile for libpng on DEC Alpha Unix
+# Copyright (C) 2000-2002 Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# where make install puts libpng.a and png.h
+prefix=/usr/local
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+LIBNAME = libpng12
+
+CC=cc
+CFLAGS=-std -w1 -I$(ZLIBINC) -O # -g -DPNG_DEBUG=1
+LDFLAGS=-L$(ZLIBLIB) -rpath $(ZLIBLIB) libpng.a -lz -lm
+
+#RANLIB=echo
+RANLIB=ranlib
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+all: $(LIBNAME).so libpng.a pngtest libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@  $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo ccopts=\"-std\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -f -s $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJS)
+	$(CC) -shared -o $@ $(OBJS) -L$(ZLIBLIB) \
+	-soname $(LIBNAME).so.$(PNGMAJ)
+
+libpng.so.3.$(PNGMIN): $(OBJS)
+	$(CC) -shared -o $@ $(OBJS) -L$(ZLIBLIB) \
+	-soname libpng.so.3
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -sf $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGVER)* $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGMIN)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -f -s libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -f -s libpng.so.3 libpng.so; \
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ); \
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -w1 -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB)  -R$(ZLIBLIB) -R$(DL) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	echo
+	echo Testing installed dynamic shared library.
+	$(CC) -w1 -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) -R$(ZLIBLIB) \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngtesti pngout.png \
+	libpng-config $(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* \
+	libpng.so.3.$(PNGMIN) \
+	libpng.pc
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
+
diff --git a/gs/libpng/scripts/makefile.dj2 b/gs/libpng/scripts/makefile.dj2
new file mode 100644
index 000000000..09045c275
--- /dev/null
+++ b/gs/libpng/scripts/makefile.dj2
@@ -0,0 +1,55 @@
+# DJGPP (DOS gcc) makefile for libpng
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# where make install will put libpng.a and png.h
+#prefix=/usr/local
+prefix=.
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+CC=gcc
+CFLAGS=-I../zlib -O
+LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
+
+RANLIB=ranlib
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o pngwtran.o \
+	pngmem.o pngerror.o pngpread.o
+
+all: libpng.a pngtest
+
+libpng.a: $(OBJS)
+	ar rc $@  $(OBJS)
+	$(RANLIB) $@
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+	coff2exe pngtest
+
+test: pngtest
+	./pngtest
+clean:
+	rm -f *.o libpng.a pngtest pngout.png
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
+
diff --git a/gs/libpng/scripts/makefile.elf b/gs/libpng/scripts/makefile.elf
new file mode 100644
index 000000000..a04b497a0
--- /dev/null
+++ b/gs/libpng/scripts/makefile.elf
@@ -0,0 +1,249 @@
+# makefile for libpng.a and libpng12.so on Linux ELF with gcc
+# Copyright (C) 1998, 1999, 2002 Greg Roelofs and Glenn Randers-Pehrson
+# Copyright (C) 1996, 1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+LIBNAME = libpng12
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+CC=gcc
+
+# where "make install" puts libpng12.a, libpng12.so*,
+# libpng12/png.h and libpng12/pngconf.h
+# Prefix must be a full pathname.
+prefix=/usr/local
+
+# Where the zlib library and include files are located.
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+ALIGN=
+# for i386:
+#ALIGN=-malign-loops=2 -malign-functions=2
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+
+# for pgcc version 2.95.1, -O3 is buggy; don't use it.
+
+CFLAGS=-I$(ZLIBINC) -Wall -O3 -funroll-loops \
+	$(ALIGN) # $(WARNMORE) -g -DPNG_DEBUG=5
+
+LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng12 -lz -lm
+LDFLAGS_A=-L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) libpng.a -lz -lm
+
+RANLIB=ranlib
+#RANLIB=echo
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -fPIC -o $@ $*.c
+
+all: libpng.a $(LIBNAME).so pngtest pngtest-static libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng.syms: png.h pngconf.h
+	$(CC) $(CFLAGS) -E -DPNG_BUILDSYMS png.h |\
+	awk -F '[\t [\]();]' 'BEGIN{print "{global:"}\
+	{ for (i=1;i+2<=NF;++i)\
+		if ($$(i)=="PNG_FUNCTION_EXPORT" && $$(i+2)=="END")\
+			print $$(i+1) ";";\
+	for (i=1;i+1<=NF;++i)\
+		if ($$(i)=="PNG_DATA_EXPORT")\
+			print $$(i+1) ";";}\
+	END{print "local: *; };"}' >$@.new
+	rm -f $@
+	mv $@.new $@
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo R_opts=\"-Wl,-rpath,$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJSDLL) libpng.syms
+	$(CC) -shared -Wl,-soname,$(LIBNAME).so.$(PNGMAJ) \
+	-Wl,-version-script,libpng.syms \
+	-o $(LIBNAME).so.$(PNGVER) \
+	$(OBJSDLL)
+
+libpng.so.3.$(PNGMIN): $(OBJSDLL) libpng.syms
+	$(CC) -shared -Wl,-soname,libpng.so.3 \
+	-Wl,-version-script,libpng.syms \
+	-o libpng.so.3.$(PNGMIN) \
+	$(OBJSDLL)
+
+pngtest: pngtest.o $(LIBNAME).so
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+pngtest-static: pngtest.o libpng.a
+	$(CC) -o pngtest-static $(CFLAGS) pngtest.o $(LDFLAGS_A)
+
+test: pngtest pngtest-static
+	@echo ""
+	@echo "   Running pngtest dynamically linked with $(LIBNAME).so:"
+	@echo ""
+	./pngtest
+	@echo ""
+	@echo "   Running pngtest statically linked with libpng.a:"
+	@echo ""
+	./pngtest-static
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -sf $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGVER)* $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGMIN)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -sf libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -sf libpng.so.3 libpng.so; \
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ); \
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) -W1, -rpath,$(DL) -Wl,-rpath,$(ZLIBLIB) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	$(CC) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a libpng.syms pngtest pngout.png libpng-config \
+	$(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* pngtest-static pngtesti \
+	libpng.so.3.$(PNGMIN) \
+	libpng.pc
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.freebsd b/gs/libpng/scripts/makefile.freebsd
new file mode 100644
index 000000000..d7d5faedd
--- /dev/null
+++ b/gs/libpng/scripts/makefile.freebsd
@@ -0,0 +1,48 @@
+# makefile for libpng under FreeBSD
+# Copyright (C) 2002 Glenn Randers-Pehrson and Andrey A. Chernov
+# For conditions of distribution and use, see copyright notice in png.h
+
+PREFIX?=        /usr/local
+SHLIB_VER?=     5
+
+LIB=		png
+SHLIB_MAJOR=	${SHLIB_VER}
+SHLIB_MINOR=	0
+NOPROFILE=	YES
+NOOBJ=          YES
+
+# where make install puts libpng.a and png.h
+DESTDIR=	${PREFIX}
+LIBDIR=		/lib
+INCS=		png.h pngconf.h
+INCSDIR=	/include/libpng
+INCDIR=		${INCSDIR}		# for 4.x bsd.lib.mk
+MAN=		libpng.3 libpngpf.3 png.5
+MANDIR=		/man/man
+SYMLINKS=       libpng/png.h ${INCSDIR}/../png.h \
+		libpng/pngconf.h ${INCSDIR}/../pngconf.h
+LDADD+=         -lm -lz
+DPADD+=         ${LIBM} ${LIBZ}
+
+CFLAGS+= -I. -DPNG_USE_PNGGCCRD
+.if (${MACHINE_ARCH} != "i386")
+CFLAGS+= -DPNG_NO_ASSEMBLER_CODE
+.endif
+
+SRCS=	png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
+	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
+	pngwtran.c pngmem.c pngerror.c pngpread.c pnggccrd.c
+
+pngtest: pngtest.o libpng.a
+	${CC} ${CFLAGS} -L. -static -o pngtest pngtest.o -lpng -lz -lm
+
+CLEANFILES= pngtest pngtest.o pngout.png
+
+test: pngtest
+	./pngtest
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+.include <bsd.lib.mk>
diff --git a/gs/libpng/scripts/makefile.gcc b/gs/libpng/scripts/makefile.gcc
new file mode 100644
index 000000000..f7fc36874
--- /dev/null
+++ b/gs/libpng/scripts/makefile.gcc
@@ -0,0 +1,66 @@
+# makefile for libpng using gcc (generic, static library)
+# Copyright (C) 2000 Cosmin Truta
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# Location of the zlib library and include files
+ZLIBINC = ../zlib
+ZLIBLIB = ../zlib
+
+# Compiler, linker, lib and other tools
+CC = gcc
+LD = $(CC)
+AR = ar rcs
+RANLIB = ranlib
+RM = rm -f
+
+CDEBUG = -g -DPNG_DEBUG=5
+LDDEBUG =
+CRELEASE = -O2
+LDRELEASE = -s
+CFLAGS = -I$(ZLIBINC) -Wall $(CRELEASE)
+LDFLAGS = -L. -L$(ZLIBLIB) -lpng -lz -lm $(LDRELEASE)
+
+# File extensions
+O=.o
+A=.a
+E=
+
+# Variables
+OBJS = png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O) \
+	pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O) \
+	pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
+
+# Targets
+all: libpng$(A) pngtest$(E)
+
+libpng$(A): $(OBJS)
+	$(AR) $@ $(OBJS)
+	$(RANLIB) $@
+
+test: pngtest$(E)
+	./pngtest$(E)
+
+pngtest$(E): pngtest$(O) libpng$(A)
+	$(LD) -o $@ pngtest$(O) $(LDFLAGS)
+
+clean:
+	$(RM) *$(O) libpng$(A) pngtest$(E) pngout.png
+
+png$(O): png.h pngconf.h
+pngerror$(O): png.h pngconf.h
+pngget$(O): png.h pngconf.h
+pngmem$(O): png.h pngconf.h
+pngpread$(O): png.h pngconf.h
+pngread$(O): png.h pngconf.h
+pngrio$(O): png.h pngconf.h
+pngrtran$(O): png.h pngconf.h
+pngrutil$(O): png.h pngconf.h
+pngset$(O): png.h pngconf.h
+pngtest$(O): png.h pngconf.h
+pngtrans$(O): png.h pngconf.h
+pngwio$(O): png.h pngconf.h
+pngwrite$(O): png.h pngconf.h
+pngwtran$(O): png.h pngconf.h
+pngwutil$(O): png.h pngconf.h
+
diff --git a/gs/libpng/scripts/makefile.gcmmx b/gs/libpng/scripts/makefile.gcmmx
new file mode 100644
index 000000000..c46c2218e
--- /dev/null
+++ b/gs/libpng/scripts/makefile.gcmmx
@@ -0,0 +1,260 @@
+# makefile for libpng.a and libpng12.so on Linux ELF with gcc using MMX
+# assembler code
+# Copyright 2002 Greg Roelofs and Glenn Randers-Pehrson
+# Copyright 1998-2001 Greg Roelofs
+# Copyright 1996-1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+# CAUTION: Do not use this makefile with gcc versions 2.7.2.2 and earlier.
+
+# WARNING: The assembler code in pnggccrd.c may not be thread safe.
+
+# NOTE:  When testing MMX performance on a multitasking system, make sure
+#        there are no floating-point programs (e.g., SETI@Home) running in
+#        the background!  Context switches between MMX and FPU are expensive.
+
+LIBNAME = libpng12
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+CC=gcc
+
+# where "make install" puts libpng12.a, libpng12.so*,
+# libpng12/png.h and libpng12/pngconf.h
+# Prefix must be a full pathname.
+prefix=/usr/local
+
+# Where the zlib library and include files are located.
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+ALIGN=
+# for i386:
+#ALIGN=-malign-loops=2 -malign-functions=2
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+
+# for pgcc version 2.95.1, -O3 is buggy; don't use it.
+
+# Remove -DPNG_THREAD_UNSAFE_OK if you need thread safety
+### for generic gcc:
+CFLAGS=-DPNG_THREAD_UNSAFE_OK -DPNG_USE_PNGGCCRD -I$(ZLIBINC) -Wall \
+	-O3 $(ALIGN) -funroll-loops \
+	-fomit-frame-pointer  # $(WARNMORE) -g -DPNG_DEBUG=5
+### for gcc 2.95.2 on 686:
+#CFLAGS=-DPNG_THREAD_UNSAFE_OK -DPNG_USE_PNGGCCRD -I$(ZLIBINC) -Wall -O3 \
+#	-mcpu=i686 -malign-double -ffast-math -fstrict-aliasing \
+#	$(ALIGN) -funroll-loops -funroll-all-loops -fomit-frame-pointer 
+### for gcc 2.7.2.3 on 486 and up:
+#CFLAGS=-DPNG_THREAD_UNSAFE_OK -DPNG_USE_PNGGCCRD -I$(ZLIBINC) -Wall -O3 \
+#	-m486 -malign-double -ffast-math \
+#	$(ALIGN) -funroll-loops -funroll-all-loops -fomit-frame-pointer 
+
+LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng12 -lz -lm
+LDFLAGS_A=-L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) libpng.a -lz -lm
+
+RANLIB=ranlib
+#RANLIB=echo
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o pnggccrd.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -fPIC -o $@ $*.c
+
+all: libpng.a $(LIBNAME).so pngtest pngtest-static libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo cppflags=\"-DPNG_THREAD_UNSAFE_OK -DPNG_USE_PNGGCCRD\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo R_opts=\"-Wl,-rpath,$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+pnggccrd.o:	pnggccrd.c png.h pngconf.h
+	$(CC) -c $(CFLAGS) -o $@ $*.c
+
+pnggccrd.pic.o:	pnggccrd.c png.h pngconf.h
+	$(CC) -c $(CFLAGS) -fPIC -o $@ pnggccrd.c
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJSDLL)
+	$(CC) -shared -Wl,-soname,$(LIBNAME).so.$(PNGMAJ) \
+	-o $(LIBNAME).so.$(PNGVER) \
+	$(OBJSDLL)
+
+libpng.so.3.$(PNGMIN): $(OBJSDLL)
+	$(CC) -shared -Wl,-soname,libpng.so.3 \
+	-o libpng.so.3.$(PNGMIN) \
+	$(OBJSDLL)
+
+pngtest: pngtest.o $(LIBNAME).so
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+pngtest-static: pngtest.o libpng.a
+	$(CC) -o pngtest-static $(CFLAGS) pngtest.o $(LDFLAGS_A)
+
+test: pngtest pngtest-static
+	@echo ""
+	@echo "   Running pngtest dynamically linked with $(LIBNAME).so:"
+	@echo ""
+	./pngtest
+	@echo ""
+	@echo "   Running pngtest statically linked with libpng.a:"
+	@echo ""
+	./pngtest-static
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -sf $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGVER)* $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGMIN)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -sf libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -sf libpng.so.3 libpng.so; \
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ); \
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) -W1, -rpath,$(DL) -Wl,-rpath,$(ZLIBLIB) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	$(CC) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngout.png libpng-config \
+	$(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* pngtest-static pngtesti \
+	libpng.so.3.$(PNGMIN) \
+	libpng.pc
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+png.o png.pic.o:		png.h pngconf.h png.c
+pngerror.o pngerror.pic.o:	png.h pngconf.h pngerror.c
+pngrio.o pngrio.pic.o:		png.h pngconf.h pngrio.c
+pngwio.o pngwio.pic.o:		png.h pngconf.h pngwio.c
+pngmem.o pngmem.pic.o:		png.h pngconf.h pngmem.c
+pngset.o pngset.pic.o:		png.h pngconf.h pngset.c
+pngget.o pngget.pic.o:		png.h pngconf.h pngget.c
+pngread.o pngread.pic.o:	png.h pngconf.h pngread.c
+pngrtran.o pngrtran.pic.o:	png.h pngconf.h pngrtran.c
+pngrutil.o pngrutil.pic.o:	png.h pngconf.h pngrutil.c
+pngtrans.o pngtrans.pic.o:	png.h pngconf.h pngtrans.c
+pngwrite.o pngwrite.pic.o:	png.h pngconf.h pngwrite.c
+pngwtran.o pngwtran.pic.o:	png.h pngconf.h pngwtran.c
+pngwutil.o pngwutil.pic.o:	png.h pngconf.h pngwutil.c
+pngpread.o pngpread.pic.o:	png.h pngconf.h pngpread.c
+
+pngtest.o:			png.h pngconf.h pngtest.c
diff --git a/gs/libpng/scripts/makefile.hp64 b/gs/libpng/scripts/makefile.hp64
new file mode 100644
index 000000000..e860e37be
--- /dev/null
+++ b/gs/libpng/scripts/makefile.hp64
@@ -0,0 +1,216 @@
+# makefile for libpng, HPUX (10.20 and 11.00) using the ANSI/C product.
+# Copyright (C) 1999-2002 Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42
+# contributed by Jim Rice and updated by Chris Schleicher, Hewlett Packard
+# For conditions of distribution and use, see copyright notice in png.h
+
+# Where the zlib library and include files are located
+ZLIBLIB=/opt/zlib/lib
+ZLIBINC=/opt/zlib/include
+
+# Note that if you plan to build a libpng shared library, zlib must also
+# be a shared library, which zlib's configure does not do.  After running
+# zlib's configure, edit the appropriate lines of makefile to read:
+#   CFLAGS=-O1 -DHAVE_UNISTD -DUSE_MAP -fPIC \
+#   LDSHARED=ld -b
+#   SHAREDLIB=libz.sl
+
+CC=cc
+CFLAGS=-I$(ZLIBINC) -O -Ae -Wl,+vnocompatwarnings +DD64 \
+-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 +Z -DHAVE_UNISTD_H -DUSE_MMAP
+# Caution: be sure you have built zlib with the same CFLAGS.
+CCFLAGS=-I$(ZLIBINC) -O -Ae -Wl,+vnocompatwarnings +DD64 \
+-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 +Z -DHAVE_UNISTD_H -DUSE_MMAP
+
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
+
+RANLIB=ranlib
+
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+LIBNAME = libpng12
+
+# where make install puts libpng.a, libpng12.sl, and png.h
+prefix=/opt/libpng
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:	.c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) +z -o $@ $*.c
+
+all: libpng.a $(LIBNAME).sl pngtest libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo ccopts=\"-Ae +DA1.1 +DS2.0\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).sl: $(LIBNAME).sl.$(PNGMAJ)
+	ln -sf $(LIBNAME).sl.$(PNGMAJ) $(LIBNAME).sl
+
+$(LIBNAME).sl.$(PNGMAJ): $(LIBNAME).sl.$(PNGVER)
+	ln -sf $(LIBNAME).sl.$(PNGVER) $(LIBNAME).sl.$(PNGMAJ)
+
+$(LIBNAME).sl.$(PNGVER): $(OBJSDLL)
+	$(LD) -b +s \
+	+h $(LIBNAME).sl.$(PNGMAJ) -o $(LIBNAME).sl.$(PNGVER) $(OBJSDLL)
+
+libpng.sl.3.$(PNGMIN): $(OBJSDLL)
+	$(LD) -b +s \
+	+h libpng.sl.3 -o libpng.sl.3.$(PNGMIN) $(OBJSDLL)
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -sf $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).sl.$(PNGVER) libpng.pc \
+	libpng.sl.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).sl.$(PNGVER)* $(DL)/$(LIBNAME).sl
+	-@/bin/rm -f $(DL)/$(LIBNAME).sl.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.sl
+	-@/bin/rm -f $(DL)/libpng.sl.3
+	-@/bin/rm -f $(DL)/libpng.sl.3.$(PNGMIN)*
+	cp $(LIBNAME).sl.$(PNGVER) $(DL)
+	cp libpng.sl.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).sl.$(PNGVER)
+	chmod 755 $(DL)/libpng.sl.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -sf libpng.sl.3.$(PNGMIN) libpng.sl.3; \
+	ln -sf libpng.sl.3 libpng.sl; \
+	ln -sf $(LIBNAME).sl.$(PNGVER) $(LIBNAME).sl.$(PNGMAJ); \
+	ln -sf $(LIBNAME).sl.$(PNGMAJ) $(LIBNAME).sl)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) $(CCFLAGS) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	echo
+	echo Testing installed dynamic shared library.
+	$(CC) $(CCFLAGS) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngtesti pngout.png \
+	libpng-config $(LIBNAME).sl $(LIBNAME).sl.$(PNGMAJ)* \
+	libpng.sl.3.$(PNGMIN) \
+	libpng.pc
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.hpgcc b/gs/libpng/scripts/makefile.hpgcc
new file mode 100644
index 000000000..d12d6cd69
--- /dev/null
+++ b/gs/libpng/scripts/makefile.hpgcc
@@ -0,0 +1,228 @@
+# makefile for libpng on HP-UX using GCC with the HP ANSI/C linker.
+# Copyright (C) 2002, Glenn Randers-Pehrson
+# Copyright (C) 2001, Laurent faillie
+# Copyright (C) 1998, 1999 Greg Roelofs
+# Copyright (C) 1996, 1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+CC=gcc
+LD=ld
+
+# where "make install" puts libpng.a, libpng.sl*, png.h and pngconf.h
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+ZLIBLIB=/opt/zlib/lib
+ZLIBINC=/opt/zlib/include
+
+# Note that if you plan to build a libpng shared library, zlib must also
+# be a shared library, which zlib's configure does not do.  After running
+# zlib's configure, edit the appropriate lines of makefile to read:
+#   CFLAGS=-O1 -DHAVE_UNISTD -DUSE_MAP -fPIC \
+#   LDSHARED=ld -b
+#   SHAREDLIB=libz.sl
+
+ALIGN=
+# for i386:
+#ALIGN=-malign-loops=2 -malign-functions=2
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+
+# for pgcc version 2.95.1, -O3 is buggy; don't use it.
+
+CFLAGS=-I$(ZLIBINC) -Wall -O3 -funroll-loops \
+	$(ALIGN) # $(WARNMORE) -g -DPNG_DEBUG=5
+#LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng12 -lz -lm
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng12 -lz -lm
+
+RANLIB=ranlib
+#RANLIB=echo
+
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+LIBNAME = libpng12
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -fPIC -o $@ $*.c
+
+all: libpng.a $(LIBNAME).sl pngtest libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).sl: $(LIBNAME).sl.$(PNGMAJ)
+	ln -sf $(LIBNAME).sl.$(PNGMAJ) $(LIBNAME).sl
+
+$(LIBNAME).sl.$(PNGMAJ): $(LIBNAME).sl.$(PNGVER)
+	ln -sf $(LIBNAME).sl.$(PNGVER) $(LIBNAME).sl.$(PNGMAJ)
+
+$(LIBNAME).sl.$(PNGVER): $(OBJSDLL)
+	$(LD) -b +s \
+	+h $(LIBNAME).sl.$(PNGMAJ) -o $(LIBNAME).sl.$(PNGVER) $(OBJSDLL)
+
+libpng.sl.3.$(PNGMIN): $(OBJSDLL)
+	$(LD) -b +s \
+	+h libpng.sl.3 -o libpng.sl.3.$(PNGMIN) $(OBJSDLL)
+
+pngtest: pngtest.o $(LIBNAME).sl
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -sf $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).sl.$(PNGVER) libpng.pc \
+	libpng.sl.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).sl.$(PNGVER)* $(DL)/$(LIBNAME).sl
+	-@/bin/rm -f $(DL)/$(LIBNAME).sl.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.sl
+	-@/bin/rm -f $(DL)/libpng.sl.3
+	-@/bin/rm -f $(DL)/libpng.sl.3.$(PNGMIN)*
+	cp $(LIBNAME).sl.$(PNGVER) $(DL)
+	cp libpng.sl.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).sl.$(PNGVER)
+	chmod 755 $(DL)/libpng.sl.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -sf libpng.sl.3.$(PNGMIN) libpng.sl.3; \
+	ln -sf libpng.sl.3 libpng.sl; \
+	ln -sf $(LIBNAME).sl.$(PNGVER) $(LIBNAME).sl.$(PNGMAJ); \
+	ln -sf $(LIBNAME).sl.$(PNGMAJ) $(LIBNAME).sl)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) -W1,-rpath,$(DL) -Wl,-rpath,$(ZLIBLIB) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	echo
+	echo Testing installed dynamic shared library.
+	$(CC) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngtesti pngout.png \
+	libpng-config $(LIBNAME).sl $(LIBNAME).sl.$(PNGMAJ)* \
+	libpng.sl.3.$(PNGMIN) \
+	libpng.pc
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.hpux b/gs/libpng/scripts/makefile.hpux
new file mode 100644
index 000000000..47b5c2632
--- /dev/null
+++ b/gs/libpng/scripts/makefile.hpux
@@ -0,0 +1,213 @@
+# makefile for libpng, HPUX (10.20 and 11.00) using the ANSI/C product.
+# Copyright (C) 1999-2002 Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42
+# contributed by Jim Rice and updated by Chris Schleicher, Hewlett Packard
+# For conditions of distribution and use, see copyright notice in png.h
+
+# Where the zlib library and include files are located
+ZLIBLIB=/opt/zlib/lib
+ZLIBINC=/opt/zlib/include
+
+# Note that if you plan to build a libpng shared library, zlib must also
+# be a shared library, which zlib's configure does not do.  After running
+# zlib's configure, edit the appropriate lines of makefile to read:
+#   CFLAGS=-O1 -DHAVE_UNISTD -DUSE_MAP -fPIC \
+#   LDSHARED=ld -b
+#   SHAREDLIB=libz.sl
+
+CC=cc
+CFLAGS=-I$(ZLIBINC) -O -Ae +DA1.1 +DS2.0
+# Caution: be sure you have built zlib with the same CFLAGS.
+CCFLAGS=-I$(ZLIBINC) -O -Ae +DA1.1 +DS2.0
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
+
+RANLIB=ranlib
+
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+LIBNAME = libpng12
+
+# where make install puts libpng.a, libpng12.sl, and png.h
+prefix=/opt/libpng
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:	.c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) +z -o $@ $*.c
+
+all: libpng.a $(LIBNAME).sl pngtest libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo ccopts=\"-Ae +DA1.1 +DS2.0\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).sl: $(LIBNAME).sl.$(PNGMAJ)
+	ln -sf $(LIBNAME).sl.$(PNGMAJ) $(LIBNAME).sl
+
+$(LIBNAME).sl.$(PNGMAJ): $(LIBNAME).sl.$(PNGVER)
+	ln -sf $(LIBNAME).sl.$(PNGVER) $(LIBNAME).sl.$(PNGMAJ)
+
+$(LIBNAME).sl.$(PNGVER): $(OBJSDLL)
+	$(LD) -b +s \
+	+h $(LIBNAME).sl.$(PNGMAJ) -o $(LIBNAME).sl.$(PNGVER) $(OBJSDLL)
+
+libpng.sl.3.$(PNGMIN): $(OBJSDLL)
+	$(LD) -b +s \
+	+h libpng.sl.3 -o libpng.sl.3.$(PNGMIN) $(OBJSDLL)
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -sf $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).sl.$(PNGVER) libpng.pc \
+	libpng.sl.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).sl.$(PNGVER)* $(DL)/$(LIBNAME).sl
+	-@/bin/rm -f $(DL)/$(LIBNAME).sl.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.sl
+	-@/bin/rm -f $(DL)/libpng.sl.3
+	-@/bin/rm -f $(DL)/libpng.sl.3.$(PNGMIN)*
+	cp $(LIBNAME).sl.$(PNGVER) $(DL)
+	cp libpng.sl.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).sl.$(PNGVER)
+	chmod 755 $(DL)/libpng.sl.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -sf libpng.sl.3.$(PNGMIN) libpng.sl.3; \
+	ln -sf libpng.sl.3 libpng.sl; \
+	ln -sf $(LIBNAME).sl.$(PNGVER) $(LIBNAME).sl.$(PNGMAJ); \
+	ln -sf $(LIBNAME).sl.$(PNGMAJ) $(LIBNAME).sl)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) $(CCFLAGS) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	echo
+	echo Testing installed dynamic shared library.
+	$(CC) $(CCFLAGS) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngtesti pngout.png \
+	libpng-config $(LIBNAME).sl $(LIBNAME).sl.$(PNGMAJ)* \
+	libpng.sl.3.$(PNGMIN) \
+	libpng.pc
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.ibmc b/gs/libpng/scripts/makefile.ibmc
new file mode 100644
index 000000000..f09a62c9e
--- /dev/null
+++ b/gs/libpng/scripts/makefile.ibmc
@@ -0,0 +1,71 @@
+# Makefile for libpng (static)
+# IBM C version 3.x for Win32 and OS/2
+# Copyright (C) 2000 Cosmin Truta
+# For conditions of distribution and use, see copyright notice in png.h
+# Notes:
+#   Derived from makefile.std
+#   All modules are compiled in C mode
+#   Tested under Win32, expected to work under OS/2
+#   Can be easily adapted for IBM VisualAge/C++ for AIX
+
+# Location of the zlib library and include files
+ZLIBINC = ../zlib
+ZLIBLIB = ../zlib
+
+# Compiler, linker, lib and other tools
+CC = icc
+LD = ilink
+AR = ilib
+RM = del
+
+CFLAGS = -I$(ZLIBINC) -Mc -O2 -W3
+LDFLAGS =
+
+# File extensions
+O=.obj
+A=.lib
+E=.exe
+
+# Variables
+OBJS = png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O) \
+	pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O) \
+	pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
+
+LIBS = libpng$(A) $(ZLIBLIB)/zlib$(A)
+
+# Targets
+all: libpng$(A) pngtest$(E)
+
+libpng$(A): $(OBJS)
+	$(AR) -out:$@ $(OBJS)
+
+test: pngtest$(E)
+	pngtest$(E)
+
+pngtest: pngtest$(E)
+
+pngtest$(E): pngtest$(O) libpng$(A)
+	$(LD) $(LDFLAGS) pngtest$(O) $(LIBS)
+
+clean:
+	$(RM) *$(O)
+	$(RM) libpng$(A)
+	$(RM) pngtest$(E)
+	$(RM) pngout.png
+
+png$(O): png.h pngconf.h
+pngerror$(O): png.h pngconf.h
+pngget$(O): png.h pngconf.h
+pngmem$(O): png.h pngconf.h
+pngpread$(O): png.h pngconf.h
+pngread$(O): png.h pngconf.h
+pngrio$(O): png.h pngconf.h
+pngrtran$(O): png.h pngconf.h
+pngrutil$(O): png.h pngconf.h
+pngset$(O): png.h pngconf.h
+pngtest$(O): png.h pngconf.h
+pngtrans$(O): png.h pngconf.h
+pngwio$(O): png.h pngconf.h
+pngwrite$(O): png.h pngconf.h
+pngwtran$(O): png.h pngconf.h
+pngwutil$(O): png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.intel b/gs/libpng/scripts/makefile.intel
new file mode 100644
index 000000000..1cabe779b
--- /dev/null
+++ b/gs/libpng/scripts/makefile.intel
@@ -0,0 +1,114 @@
+# Makefile for libpng
+# Microsoft Visual C++ with Intel C/C++ Compiler 4.0 and later
+
+# Copyright (C) 2000, Pawel Mrochen, based on makefile.msc which is
+# copyright 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# To use, do "nmake /f scripts\makefile.intel"
+
+
+# ------------------- Intel C/C++ Compiler 4.0 and later -------------------
+
+# Caution: the assembler code was introduced at libpng version 1.0.4 and has
+# not yet been thoroughly tested.
+
+# Use assembler code
+ASMCODE=-DPNG_USE_PNGVCRD
+
+# Where the zlib library and include files are located
+ZLIBLIB=..\zlib
+ZLIBINC=..\zlib
+
+# Target CPU
+CPU=6		# Pentium II
+#CPU=5		# Pentium
+
+# Calling convention
+CALLING=r	# __fastcall
+#CALLING=z	# __stdcall
+#CALLING=d	# __cdecl
+
+# Uncomment next to put error messages in a file
+#ERRFILE=>>pngerrs
+
+# --------------------------------------------------------------------------
+
+
+CC=icl -c
+CFLAGS=-O2 -G$(CPU)$(CALLING) -Qip -Qunroll4 -I$(ZLIBINC) $(ASMCODE) -nologo
+LD=link
+LDFLAGS=/SUBSYSTEM:CONSOLE /NOLOGO
+
+O=.obj
+
+OBJS=png$(O) pngset$(O) pngget$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O) \
+pngmem$(O) pngpread$(O) pngread$(O) pngerror$(O) pngwrite$(O) \
+pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O) pngvcrd$(O)
+
+
+all: test
+
+png$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngset$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngread$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngpread$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrtran$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrutil$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngvcrd$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngerror$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngmem$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrio$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwio$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngtest$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngtrans$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwrite$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwtran$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwutil$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+libpng.lib: $(OBJS)
+	if exist libpng.lib del libpng.lib
+	lib /NOLOGO /OUT:libpng.lib $(OBJS)
+
+pngtest.exe: pngtest.obj libpng.lib
+	$(LD) $(LDFLAGS) /OUT:pngtest.exe pngtest.obj libpng.lib $(ZLIBLIB)\zlib.lib
+
+test: pngtest.exe
+	pngtest.exe
+
+
+# End of makefile for libpng
diff --git a/gs/libpng/scripts/makefile.knr b/gs/libpng/scripts/makefile.knr
new file mode 100644
index 000000000..44ee538a3
--- /dev/null
+++ b/gs/libpng/scripts/makefile.knr
@@ -0,0 +1,99 @@
+# makefile for libpng
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# This makefile requires the file ansi2knr.c, which you can get
+# from the Ghostscript ftp site at ftp://ftp.cs.wisc.edu/ghost/
+# If you have libjpeg, you probably already have ansi2knr.c in the jpeg
+# source distribution.
+
+# where make install puts libpng.a and png.h
+prefix=/usr/local
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+CC=cc
+CFLAGS=-I../zlib -O
+LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
+# flags for ansi2knr
+ANSI2KNRFLAGS=
+
+RANLIB=ranlib
+#RANLIB=echo
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+all: ansi2knr libpng.a pngtest
+
+# general rule to allow ansi2knr to work
+.c.o:
+	./ansi2knr $*.c T$*.c
+	$(CC) $(CFLAGS) -c T$*.c
+	rm -f T$*.c $*.o
+	mv T$*.o $*.o
+
+ansi2knr: ansi2knr.c
+	$(CC) $(CFLAGS) $(ANSI2KNRFLAGS) -o ansi2knr ansi2knr.c
+
+libpng.a: ansi2knr $(OBJS)
+	ar rc $@  $(OBJS)
+	$(RANLIB) $@
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install: libpng.a
+	-@mkdir $(DESTDIR)$(INCPATH)
+	-@mkdir $(DESTDIR)$(INCPATH)/libpng
+	-@mkdir $(DESTDIR)$(LIBPATH)
+	-@rm -f $(DESTDIR)$(INCPATH)/png.h
+	-@rm -f $(DESTDIR)$(INCPATH)/pngconf.h
+	cp png.h $(DESTDIR)$(INCPATH)/libpng
+	cp pngconf.h $(DESTDIR)$(INCPATH)/libpng
+	chmod 644 $(DESTDIR)$(INCPATH)/libpng/png.h
+	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pngconf.h
+	(cd $(DESTDIR)$(INCPATH); ln -f -s libpng/* .)
+	cp libpng.a $(DESTDIR)$(LIBPATH)
+	chmod 644 $(DESTDIR)$(LIBPATH)/libpng.a
+
+clean:
+	rm -f *.o libpng.a pngtest pngout.png ansi2knr
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.linux b/gs/libpng/scripts/makefile.linux
new file mode 100644
index 000000000..9ba553b6a
--- /dev/null
+++ b/gs/libpng/scripts/makefile.linux
@@ -0,0 +1,234 @@
+# makefile for libpng.a and libpng12.so on Linux ELF with gcc
+# Copyright (C) 1998, 1999, 2002 Greg Roelofs and Glenn Randers-Pehrson
+# Copyright (C) 1996, 1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+LIBNAME = libpng12
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+CC=gcc
+
+# where "make install" puts libpng12.a, libpng12.so*,
+# libpng12/png.h and libpng12/pngconf.h
+# Prefix must be a full pathname.
+prefix=/usr/local
+
+# Where the zlib library and include files are located.
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+ALIGN=
+# for i386:
+#ALIGN=-malign-loops=2 -malign-functions=2
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+
+# for pgcc version 2.95.1, -O3 is buggy; don't use it.
+
+CFLAGS=-I$(ZLIBINC) -Wall -O3 -funroll-loops \
+	$(ALIGN) # $(WARNMORE) -g -DPNG_DEBUG=5
+
+LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng12 -lz -lm
+LDFLAGS_A=-L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) libpng.a -lz -lm
+
+RANLIB=ranlib
+#RANLIB=echo
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -fPIC -o $@ $*.c
+
+all: libpng.a $(LIBNAME).so pngtest pngtest-static libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo R_opts=\"-Wl,-rpath,$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJSDLL)
+	$(CC) -shared -Wl,-soname,$(LIBNAME).so.$(PNGMAJ) \
+	-o $(LIBNAME).so.$(PNGVER) \
+	$(OBJSDLL)
+
+libpng.so.3.$(PNGMIN): $(OBJSDLL)
+	$(CC) -shared -Wl,-soname,libpng.so.3 \
+	-o libpng.so.3.$(PNGMIN) \
+	$(OBJSDLL)
+
+pngtest: pngtest.o $(LIBNAME).so
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+pngtest-static: pngtest.o libpng.a
+	$(CC) -o pngtest-static $(CFLAGS) pngtest.o $(LDFLAGS_A)
+
+test: pngtest pngtest-static
+	@echo ""
+	@echo "   Running pngtest dynamically linked with $(LIBNAME).so:"
+	@echo ""
+	./pngtest
+	@echo ""
+	@echo "   Running pngtest statically linked with libpng.a:"
+	@echo ""
+	./pngtest-static
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -sf $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGVER)* $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGMIN)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -sf libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -sf libpng.so.3 libpng.so; \
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ); \
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) -W1, -rpath,$(DL) -Wl,-rpath,$(ZLIBLIB) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	$(CC) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngout.png libpng-config \
+	$(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* pngtest-static pngtesti \
+	libpng.so.3.$(PNGMIN) \
+	libpng.pc
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.mips b/gs/libpng/scripts/makefile.mips
new file mode 100644
index 000000000..f1a557df7
--- /dev/null
+++ b/gs/libpng/scripts/makefile.mips
@@ -0,0 +1,83 @@
+# makefile for libpng
+# Copyright (C) Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# where make install puts libpng.a and png.h
+prefix=/usr/local
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+CC=cc
+CFLAGS=-I../zlib -O -systype sysv -DSYSV -w -Dmips
+#CFLAGS=-O
+LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
+
+#RANLIB=ranlib
+RANLIB=echo
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+all: libpng.a pngtest
+
+libpng.a: $(OBJS)
+	ar rc $@  $(OBJS)
+	$(RANLIB) $@
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install: libpng.a
+	-@mkdir $(DESTDIR)$(INCPATH)
+	-@mkdir $(DESTDIR)$(INCPATH)/libpng
+	-@mkdir $(DESTDIR)$(LIBPATH)
+	-@rm -f $(DESTDIR)$(INCPATH)/png.h
+	-@rm -f $(DESTDIR)$(INCPATH)/pngconf.h
+	cp png.h $(DESTDIR)$(INCPATH)/libpng
+	cp pngconf.h $(DESTDIR)$(INCPATH)/libpng
+	chmod 644 $(DESTDIR)$(INCPATH)/libpng/png.h
+	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pngconf.h
+	(cd $(DESTDIR)$(INCPATH); ln -f -s libpng/* .)
+	cp libpng.a $(DESTDIR)$(LIBPATH)
+	chmod 644 $(DESTDIR)$(LIBPATH)/libpng.a
+
+clean:
+	rm -f *.o libpng.a pngtest pngout.png
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.msc b/gs/libpng/scripts/makefile.msc
new file mode 100644
index 000000000..1cbfd9149
--- /dev/null
+++ b/gs/libpng/scripts/makefile.msc
@@ -0,0 +1,86 @@
+# makefile for libpng
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+# Assumes that zlib.lib, zconf.h, and zlib.h have been copied to ..\zlib
+
+# -------- Microsoft C 5.1 and later, does not use assembler code --------
+MODEL=L
+CFLAGS=-Oait -Gs -nologo -W3 -A$(MODEL) -I..\zlib
+#-Ox generates bad code with MSC 5.1
+CC=cl
+LD=link
+LDFLAGS=/e/st:0x1500/noe
+O=.obj
+
+#uncomment next to put error messages in a file
+ERRFILE= >> pngerrs
+
+# variables
+OBJS1 = png$(O) pngset$(O) pngget$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O)
+OBJS2 = pngmem$(O) pngpread$(O) pngread$(O) pngerror$(O) pngwrite$(O)
+OBJS3 = pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O)
+
+all: libpng.lib
+
+png$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngset$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngread$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngpread$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrtran$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrutil$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngerror$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngmem$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngtest$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngtrans$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwrite$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwtran$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwutil$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+libpng.lib: $(OBJS1) $(OBJS2) $(OBJS3)
+	del libpng.lib
+	lib libpng $(OBJS1);
+	lib libpng $(OBJS2);
+	lib libpng $(OBJS3);
+
+pngtest.exe: pngtest.obj libpng.lib
+	$(LD) $(LDFLAGS) pngtest.obj,,,libpng.lib ..\zlib\zlib.lib ;
+
+test: pngtest.exe
+	pngtest
+
+# End of makefile for libpng
+
diff --git a/gs/libpng/scripts/makefile.ne12bsd b/gs/libpng/scripts/makefile.ne12bsd
new file mode 100644
index 000000000..17d317bdc
--- /dev/null
+++ b/gs/libpng/scripts/makefile.ne12bsd
@@ -0,0 +1,44 @@
+# makefile for libpng for NetBSD for the standard
+# make obj && make depend && make && make test
+# make includes && make install
+# Copyright (C) 2002 Patrick R.L. Welche
+# For conditions of distribution and use, see copyright notice in png.h
+
+# You should also run makefile.netbsd
+
+LOCALBASE?=/usr/local
+LIBDIR=	${LOCALBASE}/lib
+MANDIR= ${LOCALBASE}/man
+INCSDIR=${LOCALBASE}/include/libpng12
+
+LIB=	png12
+SHLIB_MAJOR=	0
+SHLIB_MINOR=	1.2.8
+SRCS=	pnggccrd.c png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
+		pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
+		pngwtran.c pngmem.c pngerror.c pngpread.c
+INCS=	png.h pngconf.h
+MAN=	libpng.3 libpngpf.3 png.5
+
+CPPFLAGS+=-I${.CURDIR} -DPNG_USE_PNGGCCRD
+
+# something like this for mmx assembler, but it core dumps for me at the moment
+# .if ${MACHINE_ARCH} == "i386"
+#   CPPFLAGS+=-DPNG_THREAD_UNSAFE_OK
+#   MKLINT= no
+# .else
+    CPPFLAGS+=-DPNG_NO_ASSEMBLER_CODE
+# .endif
+
+CLEANFILES+=pngtest.o pngtest
+
+pngtest.o:	pngtest.c
+	${CC} -c ${CPPFLAGS} ${CFLAGS} ${.ALLSRC} -o ${.TARGET}
+
+pngtest:	pngtest.o libpng.a
+	${CC} ${LDFLAGS} ${.ALLSRC} -o${.TARGET} -lz -lm
+
+test:	pngtest
+	cd ${.CURDIR} && ${.OBJDIR}/pngtest
+
+.include <bsd.lib.mk>
diff --git a/gs/libpng/scripts/makefile.netbsd b/gs/libpng/scripts/makefile.netbsd
new file mode 100644
index 000000000..52fa3397e
--- /dev/null
+++ b/gs/libpng/scripts/makefile.netbsd
@@ -0,0 +1,44 @@
+# makefile for libpng for NetBSD for the standard
+# make obj && make depend && make && make test
+# make includes && make install
+# Copyright (C) 2002 Patrick R.L. Welche
+# For conditions of distribution and use, see copyright notice in png.h
+
+# You should also run makefile.ne0bsd
+
+LOCALBASE?=/usr/local
+LIBDIR=	${LOCALBASE}/lib
+MANDIR= ${LOCALBASE}/man
+INCSDIR=${LOCALBASE}/include/libpng
+
+LIB=	png
+SHLIB_MAJOR=	3
+SHLIB_MINOR=	1.2.8
+SRCS=	pnggccrd.c png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
+		pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
+		pngwtran.c pngmem.c pngerror.c pngpread.c
+INCS=	png.h pngconf.h
+MAN=	libpng.3 libpngpf.3 png.5
+
+CPPFLAGS+=-I${.CURDIR} -DPNG_USE_PNGGCCRD
+
+# something like this for mmx assembler, but it core dumps for me at the moment
+# .if ${MACHINE_ARCH} == "i386"
+#   CPPFLAGS+=-DPNG_THREAD_UNSAFE_OK
+#   MKLINT= no
+# .else
+    CPPFLAGS+=-DPNG_NO_ASSEMBLER_CODE
+# .endif
+
+CLEANFILES+=pngtest.o pngtest
+
+pngtest.o:	pngtest.c
+	${CC} -c ${CPPFLAGS} ${CFLAGS} ${.ALLSRC} -o ${.TARGET}
+
+pngtest:	pngtest.o libpng.a
+	${CC} ${LDFLAGS} ${.ALLSRC} -o${.TARGET} -lz -lm
+
+test:	pngtest
+	cd ${.CURDIR} && ${.OBJDIR}/pngtest
+
+.include <bsd.lib.mk>
diff --git a/gs/libpng/scripts/makefile.openbsd b/gs/libpng/scripts/makefile.openbsd
new file mode 100644
index 000000000..5d401a32d
--- /dev/null
+++ b/gs/libpng/scripts/makefile.openbsd
@@ -0,0 +1,72 @@
+# makefile for libpng
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+PREFIX?= /usr/local
+LIBDIR=	${PREFIX}/lib
+MANDIR= ${PREFIX}/man/cat
+
+SHLIB_MAJOR=	0
+SHLIB_MINOR=	1.2.8
+
+LIB=	png
+SRCS=	png.c pngerror.c pnggccrd.c pngget.c pngmem.c pngpread.c \
+	pngread.c pngrio.c pngrtran.c pngrutil.c pngset.c pngtrans.c \
+	pngwio.c pngwrite.c pngwtran.c pngwutil.c
+
+HDRS=	png.h pngconf.h
+
+CFLAGS+= -Wall
+CPPFLAGS+= -I${.CURDIR} -DPNG_NO_ASSEMBLER_CODE -DPNG_USE_PNGGCCRD
+
+NOPROFILE= Yes
+
+CLEANFILES+= pngtest.o pngtest
+
+MAN=	libpng.3 libpngpf.3 png.5
+DOCS=	ANNOUNCE CHANGES LICENSE README libpng.txt
+
+pngtest.o:	pngtest.c
+	${CC} ${CPPFLAGS} ${CFLAGS} -c ${.ALLSRC} -o ${.TARGET}
+
+pngtest:	pngtest.o
+	${CC} ${LDFLAGS} ${.ALLSRC} -o ${.TARGET} -L${.OBJDIR} -lpng -lz -lm
+
+test:	pngtest
+	cd ${.OBJDIR} && env \
+		LD_LIBRARY_PATH="${.OBJDIR}" ${.OBJDIR}/pngtest
+
+beforeinstall:
+	if [ ! -d ${DESTDIR}${PREFIX}/include/libpng ]; then \
+	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${PREFIX}/include/libpng; \
+	fi
+	if [ ! -d ${DESTDIR}${LIBDIR} ]; then \
+	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${LIBDIR}; \
+	fi
+	if [ ! -d ${DESTDIR}${LIBDIR}/debug ]; then \
+	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${LIBDIR}/debug; \
+	fi
+	if [ ! -d ${DESTDIR}${MANDIR}3 ]; then \
+	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${MANDIR}3; \
+	fi
+	if [ ! -d ${DESTDIR}${MANDIR}5 ]; then \
+	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${MANDIR}5; \
+	fi
+	if [ ! -d ${DESTDIR}${PREFIX}/share/doc/png ]; then \
+	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${PREFIX}/share/doc/png; \
+	fi
+
+afterinstall:
+	@rm -f ${DESTDIR}${LIBDIR}/libpng_pic.a
+	@rm -f ${DESTDIR}${LIBDIR}/debug/libpng.a
+	@rm -f ${DESTDIR}${PREFIX}/include/png.h
+	@rm -f ${DESTDIR}${PREFIX}/include/pngconf.h
+	@rmdir ${DESTDIR}${LIBDIR}/debug 2>/dev/null || true
+	${INSTALL} ${INSTALL_COPY} -o ${SHAREOWN} -g ${SHAREGRP} \
+		-m ${NONBINMODE} ${HDRS} ${DESTDIR}${PREFIX}/include/libpng
+	${INSTALL} ${INSTALL_COPY} -o ${SHAREOWN} -g ${SHAREGRP} \
+		-m ${NONBINMODE} ${HDRS} ${DESTDIR}${PREFIX}/include
+	${INSTALL} ${INSTALL_COPY} -o ${SHAREOWN} -g ${SHAREGRP} \
+		-m ${NONBINMODE} ${DOCS} ${DESTDIR}${PREFIX}/share/doc/png
+
+.include <bsd.lib.mk>
diff --git a/gs/libpng/scripts/makefile.os2 b/gs/libpng/scripts/makefile.os2
new file mode 100644
index 000000000..588067d25
--- /dev/null
+++ b/gs/libpng/scripts/makefile.os2
@@ -0,0 +1,69 @@
+# makefile for libpng on OS/2 with gcc
+# For conditions of distribution and use, see copyright notice in png.h
+
+# Related files: pngos2.def
+
+CC=gcc -Zomf -s
+
+# Where the zlib library and include files are located
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+CFLAGS=-I$(ZLIBINC) -Wall -O6 -funroll-loops -malign-loops=2 \
+	-malign-functions=2 #$(WARNMORE) -g -DPNG_DEBUG=5
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lzdll -Zcrtdll
+AR=emxomfar
+
+PNGLIB=png.lib
+IMPLIB=emximp
+SHAREDLIB=png.dll
+SHAREDLIBIMP=pngdll.lib
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+.SUFFIXES:      .c .o
+
+all: $(PNGLIB) $(SHAREDLIB) $(SHAREDLIBIMP)
+
+$(PNGLIB): $(OBJS)
+	$(AR) rc $@ $(OBJS)
+
+$(SHAREDLIB): $(OBJS) pngos2.def
+	$(CC) $(LDFLAGS) -Zdll -o $@ $^
+
+$(SHAREDLIBIMP): pngos2.def
+	$(IMPLIB) -o $@ $^
+
+pngtest.exe: pngtest.o png.dll pngdll.lib
+	$(CC) -o $@ $(CFLAGS) $< $(LDFLAGS)
+
+test: pngtest.exe
+	./pngtest.exe
+
+clean:
+	rm -f *.o $(PNGLIB) png.dll pngdll.lib pngtest.exe pngout.png
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.sco b/gs/libpng/scripts/makefile.sco
new file mode 100644
index 000000000..f3642317f
--- /dev/null
+++ b/gs/libpng/scripts/makefile.sco
@@ -0,0 +1,212 @@
+# makefile for SCO OSr5  ELF and Unixware 7 with Native cc
+# Contributed by Mike Hopkirk (hops@sco.com) modified from Makefile.lnx
+#   force ELF build dynamic linking, SONAME setting in lib and RPATH in app
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# Copyright (C) 1998 Greg Roelofs
+# Copyright (C) 1996, 1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+CC=cc
+
+# where make install puts libpng.a, libpng.so*, and png.h
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+CFLAGS= -dy -belf -I$(ZLIBINC) -O3
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng12 -lz -lm
+
+#RANLIB=ranlib
+RANLIB=echo
+
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+LIBNAME = libpng12
+
+INCPATH=$(prefix)/include/libpng
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -KPIC -o $@ $*.c
+
+all: libpng.a $(LIBNAME).so pngtest libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo ccopts=\"-belf\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -f -s $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJSDLL)
+	$(CC) -G  -Wl,-h,$(LIBNAME).so.$(PNGMAJ) -o $(LIBNAME).so.$(PNGVER) \
+	 $(OBJSDLL)
+
+libpng.so.3.$(PNGMIN): $(OBJSDLL)
+	$(CC) -G  -Wl,-h,libpng.so.3 -o libpng.so.3.$(PNGMIN) \
+	$(OBJSDLL)
+
+pngtest: pngtest.o $(LIBNAME).so
+	LD_RUN_PATH=.:$(ZLIBLIB) $(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	-@/bin/rm -f $(DI)/png.h
+	-@/bin/rm -f $(DI)/pngconf.h
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -f -s $(LIBNAME) libpng; ln -f -s $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -f -s $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGVER)* $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGMIN)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -f -s libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -f -s libpng.so.3 libpng.so; \
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ); \
+	ln -f -s $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -f -s $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -f -s $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) $(CFLAGS) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	$(CC) $(CFLAGS) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngout.png libpng-config \
+	$(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* pngtest-static pngtesti \
+	libpng.so.3.$(PNGMIN) \
+	libpng.pc
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.sggcc b/gs/libpng/scripts/makefile.sggcc
new file mode 100644
index 000000000..5010daa9d
--- /dev/null
+++ b/gs/libpng/scripts/makefile.sggcc
@@ -0,0 +1,224 @@
+# makefile for libpng.a and libpng12.so, SGI IRIX with 'cc'
+# Copyright (C) 2001-2002 Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# Where make install puts libpng.a, libpng12.so, and libpng12/png.h
+# Prefix must be a full pathname.
+
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib32
+#ZLIBINC=/usr/local/include
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+LIBNAME=libpng12
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+CC=gcc
+
+# ABI can be blank to use default for your system, -32, -o32, -n32, or -64
+# See "man abi".  zlib must be built with the same ABI.
+ABI=
+
+WARNMORE= # -g -DPNG_DEBUG=5
+CFLAGS=$(ABI) -I$(ZLIBINC) -O2 $(WARNMORE) -fPIC -mabi=n32
+LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm
+LDSHARED=cc $(ABI) -shared -soname $(LIBNAME).so.$(PNGMAJ) \
+  -set_version sgi$(PNGMAJ).0
+LDLEGACY=cc $(ABI) -shared -soname libpng.so.3 \
+  -set_version sgi$3.0
+# See "man dso" for info about shared objects
+
+RANLIB=echo
+#RANLIB=ranlib
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+#LIBPATH=$(prefix)/lib32
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = pnggccrd.o png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+all: libpng.a pngtest shared libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+shared: $(LIBNAME).so.$(PNGVER)
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo ccopts=\"$(ABI)\"; \
+	echo ldopts=\"$(ABI)\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo libdir=\"$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJS)
+	$(LDSHARED) -o $@ $(OBJS)
+	rm -f $(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)
+
+libpng.so.3.$(PNGMIN): $(OBJS)
+	$(LDLEGACY) -o $@ $(OBJS)
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	echo
+	echo Testing local static library.
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -sf $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGVER)* $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGMIN)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -sf libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -sf libpng.so.3 libpng.so; \
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ); \
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) \
+           -rpath $(ZLIBLIB):$(DL)\
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	echo
+	echo Testing installed dynamic shared library.
+	$(CC) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) \
+           -rpath $(ZLIBLIB):`$(BINPATH)/libpng12-config --libdir` \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	rm -f *.o libpng.a pngtest pngtesti pngout.png libpng.pc libpng-config \
+	$(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* \
+	libpng.so.3.$(PNGMIN) \
+	so_locations
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
+pnggccrd.o: png.h pngconf.h
+
diff --git a/gs/libpng/scripts/makefile.sgi b/gs/libpng/scripts/makefile.sgi
new file mode 100644
index 000000000..584da7cca
--- /dev/null
+++ b/gs/libpng/scripts/makefile.sgi
@@ -0,0 +1,230 @@
+# makefile for libpng.a and libpng12.so, SGI IRIX with 'cc'
+# Copyright (C) 2001-2002 Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+LIBNAME=libpng12
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+# Where make install puts libpng.a, libpng12.so, and libpng12/png.h
+# Prefix must be a full pathname.
+
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib32
+#ZLIBINC=/usr/local/include
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+CC=cc
+
+# ABI can be blank to use default for your system, -32, -o32, -n32, or -64
+# See "man abi".  zlib must be built with the same ABI.
+ABI=
+
+WARNMORE=-fullwarn
+# Note: -KPIC is the default anyhow
+#CFLAGS= $(ABI) -I$(ZLIBINC) -O $(WARNMORE) -KPIC -DPNG_USE_PNGGCCRD # -g -DPNG_DEBUG=5
+CFLAGS=$(ABI) -I$(ZLIBINC) -O $(WARNMORE) -DPNG_USE_PNGGCCRD \
+  -DPNG_NO_ASSEMBLER_CODE
+LDFLAGS_A=$(ABI) -L. -L$(ZLIBLIB) -lpng12 -lz -lm
+LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm
+LDSHARED=cc $(ABI) -shared -soname $(LIBNAME).so.$(PNGMAJ) \
+  -set_version sgi$(PNGMAJ).0
+LDLEGACY=cc $(ABI) -shared -soname libpng.so.3 \
+  -set_version sgi$3.0
+# See "man dso" for info about shared objects
+
+RANLIB=echo
+#RANLIB=ranlib
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+#LIBPATH=$(prefix)/lib32
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = pnggccrd.o png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+all: libpng.a pngtest shared libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+shared: $(LIBNAME).so.$(PNGVER)
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo cppflags=\"-DPNG_USE_PNGGCCRD -DPNG_NO_ASSEMBLER_CODE\"; \
+	echo ccopts=\"$(ABI)\"; \
+	echo ldopts=\"$(ABI)\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo libdir=\"$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJS)
+	$(LDSHARED) -o $@ $(OBJS)
+	rm -f $(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)
+
+libpng.so.3.$(PNGMIN): $(OBJS)
+	$(LDLEGACY) -o $@ $(OBJS)
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	echo
+	echo Testing local static library.
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -sf $(LIBNAME) libpng; ln -sf $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -sf $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGVER)* $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGMIN)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -sf libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -sf libpng.so.3 libpng.so; \
+	ln -sf $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ); \
+	ln -sf $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -sf $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -sf $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(DL) -L$(ZLIBLIB) \
+           -rpath $(ZLIBLIB):$(DL) \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags`
+	./pngtestd pngtest.png
+
+test-installed:
+	echo
+	echo Testing installed dynamic shared library.
+	$(CC) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -L$(ZLIBLIB) \
+           -rpath $(ZLIBLIB):`$(BINPATH)/libpng12-config --libdir` \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags`
+	./pngtesti pngtest.png
+
+clean:
+	rm -f *.o libpng.a pngtest pngtesti pngout.png libpng.pc libpng-config \
+	$(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* \
+	libpng.so.3.$(PNGMIN) \
+	so_locations
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
+pnggccrd.o: png.h pngconf.h
+
diff --git a/gs/libpng/scripts/makefile.so9 b/gs/libpng/scripts/makefile.so9
new file mode 100644
index 000000000..a53a80dfd
--- /dev/null
+++ b/gs/libpng/scripts/makefile.so9
@@ -0,0 +1,234 @@
+# makefile for libpng on Solaris 9 (beta) with Forte cc
+# Updated by Chad Schrock for Solaris 9
+# Contributed by William L. Sebok, based on makefile.linux
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# Copyright (C) 1998-2001 Greg Roelofs
+# Copyright (C) 1996-1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+# gcc 2.95 doesn't work.
+CC=cc
+
+# Where make install puts libpng.a, libpng.so*, and png.h
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+# Changing these to ../zlib poses a security risk.  If you want
+# to have zlib in an adjacent directory, specify the full path instead of "..".
+#ZLIBLIB=../zlib
+#ZLIBINC=../zlib
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+#Use the preinstalled zlib that comes with Solaris 9:
+ZLIBLIB=/usr/lib
+ZLIBINC=/usr/include
+
+#WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+#CFLAGS=-I$(ZLIBINC) -Wall -O3 $(WARNMORE) -g -DPNG_DEBUG=5
+CFLAGS=-I$(ZLIBINC) -O3
+LDFLAGS=-L. -R. -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng12 -lz -lm
+
+#RANLIB=ranlib
+RANLIB=echo
+
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+LIBNAME = libpng12
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -KPIC -o $@ $*.c
+
+all: libpng.a $(LIBNAME).so pngtest libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo R_opts=\"-R$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -f -s $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJSDLL)
+	@case "`type ld`" in *ucb*) \
+	echo; \
+	echo '## WARNING:'; \
+	echo '## The commands "CC" and "LD" must NOT refer to /usr/ucb/cc'; \
+	echo '## and /usr/ucb/ld.  If they do, you need to adjust your PATH'; \
+	echo '## environment variable to put /usr/ccs/bin ahead of /usr/ucb.'; \
+	echo '## The environment variable LD_LIBRARY_PATH should not be set'; \
+	echo '## at all.  If it is, things are likely to break because of'; \
+	echo '## the libucb dependency that is created.'; \
+	echo; \
+	;; \
+	esac
+	$(LD) -G -h $(LIBNAME).so.$(PNGMAJ) \
+	 -o $(LIBNAME).so.$(PNGVER) $(OBJSDLL)
+
+libpng.so.3.$(PNGMIN): $(OBJS)
+	$(LD) -G -h libpng.so.3 \
+	 -o libpng.so.3.$(PNGMIN) $(OBJSDLL)
+
+pngtest: pngtest.o $(LIBNAME).so
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -f -s $(LIBNAME) libpng; ln -f -s $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -f -s $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGVER)* $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGMIN)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -f -s libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -f -s libpng.so.3 libpng.so; \
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ); \
+	ln -f -s $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so)
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -f -s $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -f -s $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags` \
+	   -L$(DL) -L$(ZLIBLIB)  -R$(ZLIBLIB) -R$(DL)
+	./pngtestd pngtest.png
+
+test-installed:
+	echo
+	echo Testing installed dynamic shared library.
+	$(CC) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags` \
+	   -L$(ZLIBLIB) -R$(ZLIBLIB)
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngtesti pngout.png \
+	libpng-config $(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* \
+	libpng.so.3.$(PNGMIN) \
+	libpng.pc
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.solaris b/gs/libpng/scripts/makefile.solaris
new file mode 100644
index 000000000..8e053f8aa
--- /dev/null
+++ b/gs/libpng/scripts/makefile.solaris
@@ -0,0 +1,231 @@
+# makefile for libpng on Solaris 2.x with gcc
+# Copyright (C) 2004 Glenn Randers-Pehrson
+# Contributed by William L. Sebok, based on makefile.linux
+# Copyright (C) 1998 Greg Roelofs
+# Copyright (C) 1996, 1997 Andreas Dilger
+# For conditions of distribution and use, see copyright notice in png.h
+
+CC=gcc
+
+# Where make install puts libpng.a, libpng12.so*, and png.h
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+# Changing these to ../zlib poses a security risk.  If you want
+# to have zlib in an adjacent directory, specify the full path instead of "..".
+#ZLIBLIB=../zlib
+#ZLIBINC=../zlib
+
+ZLIBLIB=/usr/local/lib
+ZLIBINC=/usr/local/include
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+CFLAGS=-I$(ZLIBINC) -Wall -O \
+	# $(WARNMORE) -g -DPNG_DEBUG=5
+LDFLAGS=-L. -R. -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng12 -lz -lm
+
+#RANLIB=ranlib
+RANLIB=echo
+
+PNGMAJ = 0
+PNGMIN = 1.2.8
+PNGVER = $(PNGMAJ).$(PNGMIN)
+LIBNAME = libpng12
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+MANPATH=$(prefix)/man
+BINPATH=$(prefix)/bin
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+DB=$(DESTDIR)$(BINPATH)
+DI=$(DESTDIR)$(INCPATH)
+DL=$(DESTDIR)$(LIBPATH)
+DM=$(DESTDIR)$(MANPATH)
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -fPIC -o $@ $*.c
+
+all: libpng.a $(LIBNAME).so pngtest libpng.pc libpng-config
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.pc:
+	cat scripts/libpng.pc.in | sed -e s\!@PREFIX@!$(prefix)! > libpng.pc
+
+libpng-config:
+	( cat scripts/libpng-config-head.in; \
+	echo prefix=\"$(prefix)\"; \
+	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
+	echo cppflags=\"-DPNG_USE_PNGGCCRD -DPNG_NO_ASSEMBLER_CODE\"; \
+	echo L_opts=\"-L$(LIBPATH)\"; \
+	echo R_opts=\"-R$(LIBPATH)\"; \
+	echo libs=\"-lpng12 -lz -lm\"; \
+	cat scripts/libpng-config-body.in ) > libpng-config
+	chmod +x libpng-config
+
+$(LIBNAME).so: $(LIBNAME).so.$(PNGMAJ)
+	ln -f -s $(LIBNAME).so.$(PNGMAJ) $(LIBNAME).so
+
+$(LIBNAME).so.$(PNGMAJ): $(LIBNAME).so.$(PNGVER)
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ)
+
+$(LIBNAME).so.$(PNGVER): $(OBJSDLL)
+	@case "`type ld`" in *ucb*) \
+	echo; \
+	echo '## WARNING:'; \
+	echo '## The commands "CC" and "LD" must NOT refer to /usr/ucb/cc'; \
+	echo '## and /usr/ucb/ld.  If they do, you need to adjust your PATH'; \
+	echo '## environment variable to put /usr/ccs/bin ahead of /usr/ucb.'; \
+	echo '## The environment variable LD_LIBRARY_PATH should not be set'; \
+	echo '## at all.  If it is, things are likely to break because of'; \
+	echo '## the libucb dependency that is created.'; \
+	echo; \
+	;; \
+	esac
+	$(LD) -G -h $(LIBNAME).so.$(PNGMAJ) \
+	 -o $(LIBNAME).so.$(PNGVER) $(OBJSDLL)
+
+libpng.so.3.$(PNGMIN): $(OBJS)
+	$(LD) -G -h libpng.so.3 \
+	 -o libpng.so.3.$(PNGMIN) $(OBJSDLL)
+
+pngtest: pngtest.o $(LIBNAME).so
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install-headers: png.h pngconf.h
+	-@if [ ! -d $(DI) ]; then mkdir $(DI); fi
+	-@if [ ! -d $(DI)/$(LIBNAME) ]; then mkdir $(DI)/$(LIBNAME); fi
+	cp png.h pngconf.h $(DI)/$(LIBNAME)
+	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h
+	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h
+	-@/bin/rm -f $(DI)/libpng
+	(cd $(DI); ln -f -s $(LIBNAME) libpng; ln -f -s $(LIBNAME)/* .)
+
+install-static: install-headers libpng.a
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	cp libpng.a $(DL)/$(LIBNAME).a
+	chmod 644 $(DL)/$(LIBNAME).a
+	-@/bin/rm -f $(DL)/libpng.a
+	(cd $(DL); ln -f -s $(LIBNAME).a libpng.a)
+
+install-shared: install-headers $(LIBNAME).so.$(PNGVER) libpng.pc \
+	libpng.so.3.$(PNGMIN)
+	-@if [ ! -d $(DL) ]; then mkdir $(DL); fi
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGVER)* $(DL)/$(LIBNAME).so
+	-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)
+	-@/bin/rm -f $(DL)/libpng.so
+	-@/bin/rm -f $(DL)/libpng.so.3
+	-@/bin/rm -f $(DL)/libpng.so.3.$(PNGMIN)*
+	cp $(LIBNAME).so.$(PNGVER) $(DL)
+	cp libpng.so.3.$(PNGMIN) $(DL)
+	chmod 755 $(DL)/$(LIBNAME).so.$(PNGVER)
+	chmod 755 $(DL)/libpng.so.3.$(PNGMIN)
+	(cd $(DL); \
+	ln -f -s libpng.so.3.$(PNGMIN) libpng.so.3; \
+	ln -f -s libpng.so.3 libpng.so; \
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so; \
+	ln -f -s $(LIBNAME).so.$(PNGVER) $(LIBNAME).so.$(PNGMAJ))
+	-@if [ ! -d $(DL)/pkgconfig ]; then mkdir $(DL)/pkgconfig; fi
+	-@/bin/rm -f $(DL)/pkgconfig/$(LIBNAME).pc
+	-@/bin/rm -f $(DL)/pkgconfig/libpng.pc
+	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
+	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
+	(cd $(DL)/pkgconfig; ln -f -s $(LIBNAME).pc libpng.pc)
+
+install-man: libpng.3 libpngpf.3 png.5
+	-@if [ ! -d $(DM) ]; then mkdir $(DM); fi
+	-@if [ ! -d $(DM)/man3 ]; then mkdir $(DM)/man3; fi
+	-@/bin/rm -f $(DM)/man3/libpng.3
+	-@/bin/rm -f $(DM)/man3/libpngpf.3
+	cp libpng.3 $(DM)/man3
+	cp libpngpf.3 $(DM)/man3
+	-@if [ ! -d $(DM)/man5 ]; then mkdir $(DM)/man5; fi
+	-@/bin/rm -f $(DM)/man5/png.5
+	cp png.5 $(DM)/man5
+
+install-config: libpng-config
+	-@if [ ! -d $(DB) ]; then mkdir $(DB); fi
+	-@/bin/rm -f $(DB)/libpng-config
+	-@/bin/rm -f $(DB)/$(LIBNAME)-config
+	cp libpng-config $(DB)/$(LIBNAME)-config
+	chmod 755 $(DB)/$(LIBNAME)-config
+	(cd $(DB); ln -s -f $(LIBNAME)-config libpng-config)
+
+install: install-static install-shared install-man install-config
+
+# If you installed in $(DESTDIR), test-installed won't work until you
+# move the library to its final location.  Use test-dd to test it
+# before then.
+
+test-dd:
+	echo
+	echo Testing installed dynamic shared library in $(DL).
+	$(CC) -I$(DI) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -o pngtestd `$(BINPATH)/libpng12-config --ldflags` \
+	   -L$(DL) -L$(ZLIBLIB) -R$(ZLIBLIB) -R$(DL)
+	./pngtestd pngtest.png
+
+test-installed:
+	echo
+	echo Testing installed dynamic shared library.
+	$(CC) -I$(ZLIBINC) \
+	   `$(BINPATH)/libpng12-config --cflags` pngtest.c \
+	   -o pngtesti `$(BINPATH)/libpng12-config --ldflags` \
+	   -L$(ZLIBLIB) -R$(ZLIBLIB)
+	./pngtesti pngtest.png
+
+clean:
+	/bin/rm -f *.o libpng.a pngtest pngtesti pngout.png \
+	libpng-config $(LIBNAME).so $(LIBNAME).so.$(PNGMAJ)* \
+	libpng.so.3.$(PNGMIN) \
+	libpng.pc
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h
diff --git a/gs/libpng/scripts/makefile.std b/gs/libpng/scripts/makefile.std
new file mode 100644
index 000000000..5d1f5290d
--- /dev/null
+++ b/gs/libpng/scripts/makefile.std
@@ -0,0 +1,89 @@
+# makefile for libpng
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# where make install puts libpng.a and png.h
+prefix=/usr/local
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+CC=cc
+CFLAGS=-I$(ZLIBINC) -O # -g -DPNG_DEBUG=5
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
+
+#RANLIB=echo
+RANLIB=ranlib
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+all: libpng.a pngtest
+
+libpng.a: $(OBJS)
+	ar rc $@  $(OBJS)
+	$(RANLIB) $@
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install: libpng.a
+	-@mkdir $(DESTDIR)$(INCPATH)
+	-@mkdir $(DESTDIR)$(INCPATH)/libpng
+	-@mkdir $(DESTDIR)$(LIBPATH)
+	-@rm -f $(DESTDIR)$(INCPATH)/png.h
+	-@rm -f $(DESTDIR)$(INCPATH)/pngconf.h
+	cp png.h $(DESTDIR)$(INCPATH)/libpng
+	cp pngconf.h $(DESTDIR)$(INCPATH)/libpng
+	chmod 644 $(DESTDIR)$(INCPATH)/libpng/png.h
+	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pngconf.h
+	(cd $(DESTDIR)$(INCPATH); ln -f -s libpng/* .)
+	cp libpng.a $(DESTDIR)$(LIBPATH)
+	chmod 644 $(DESTDIR)$(LIBPATH)/libpng.a
+
+clean:
+	rm -f *.o libpng.a pngtest pngout.png
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
+
diff --git a/gs/libpng/scripts/makefile.sunos b/gs/libpng/scripts/makefile.sunos
new file mode 100644
index 000000000..70a6e88af
--- /dev/null
+++ b/gs/libpng/scripts/makefile.sunos
@@ -0,0 +1,93 @@
+# makefile for libpng
+# Copyright (C) 2002 Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# where make install puts libpng.a and png.h
+prefix=/usr/local
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+# override DESTDIR= on the make install command line to easily support
+# installing into a temporary location.  Example:
+#
+#    make install DESTDIR=/tmp/build/libpng
+#
+# If you're going to install into a temporary location
+# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
+# you execute make install.
+DESTDIR=
+
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow -Wconversion \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes
+CC=gcc
+CFLAGS=-I$(ZLIBINC) -O # $(WARNMORE) -DPNG_DEBUG=5
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
+
+RANLIB=ranlib
+#RANLIB=echo
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+all: libpng.a pngtest
+
+libpng.a: $(OBJS)
+	ar rc $@  $(OBJS)
+	$(RANLIB) $@
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install: libpng.a
+	-@mkdir $(DESTDIR)$(INCPATH)
+	-@mkdir $(DESTDIR)$(INCPATH)/libpng
+	-@mkdir $(DESTDIR)$(LIBPATH)
+	-@rm -f $(DESTDIR)$(INCPATH)/png.h
+	-@rm -f $(DESTDIR)$(INCPATH)/pngconf.h
+	cp png.h $(DESTDIR)$(INCPATH)/libpng
+	cp pngconf.h $(DESTDIR)$(INCPATH)/libpng
+	chmod 644 $(DESTDIR)$(INCPATH)/libpng/png.h
+	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pngconf.h
+	(cd $(DESTDIR)$(INCPATH); ln -f -s libpng/* .)
+	cp libpng.a $(DESTDIR)$(LIBPATH)
+	chmod 644 $(DESTDIR)$(LIBPATH)/libpng.a
+
+clean:
+	rm -f *.o libpng.a pngtest pngout.png
+
+DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO
+writelock:
+	chmod a-w *.[ch35] $(DOCS) scripts/*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
+
diff --git a/gs/libpng/scripts/makefile.tc3 b/gs/libpng/scripts/makefile.tc3
new file mode 100644
index 000000000..21435a68e
--- /dev/null
+++ b/gs/libpng/scripts/makefile.tc3
@@ -0,0 +1,89 @@
+# Makefile for libpng
+# TurboC/C++ (Note: All modules are compiled in C mode)
+
+# To use, do "make -fmakefile.tc3"
+
+# ----- Turbo C 3.00 (can be modified to work with earlier versions) -----
+
+MODEL=l
+CFLAGS=-O2 -Z -m$(MODEL) -I..\zlib
+#CFLAGS=-D_NO_PROTO -O2 -Z -m$(MODEL) -I..\zlib  # Turbo C older than 3.00
+CC=tcc
+LD=tcc
+LIB=tlib
+LDFLAGS=-m$(MODEL) -L..\zlib
+O=.obj
+E=.exe
+
+# variables
+OBJS1 = png$(O) pngset$(O) pngget$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O)
+OBJS2 = pngmem$(O) pngpread$(O) pngread$(O) pngerror$(O) pngwrite$(O)
+OBJS3 = pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O)
+OBJSL1 = +png$(O) +pngset$(O) +pngget$(O) +pngrutil$(O) +pngtrans$(O)
+OBJSL2 = +pngwutil$(O) +pngmem$(O) +pngpread$(O) +pngread$(O) +pngerror$(O)
+OBJSL3 = +pngwrite$(O) +pngrtran$(O) +pngwtran$(O) +pngrio$(O) +pngwio$(O)
+
+all: libpng$(MODEL).lib pngtest$(E)
+
+pngtest: pngtest$(E)
+
+test: pngtest$(E)
+	pngtest$(E)
+
+png$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngset$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngget$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngread$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngpread$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngrtran$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngrutil$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngerror$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngmem$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngrio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngwio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngtest$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngtrans$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngwrite$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngwtran$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngwutil$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+libpng$(MODEL).lib: $(OBJS1) $(OBJS2) $(OBJS3)
+	$(LIB) libpng$(MODEL) +$(OBJSL1)
+	$(LIB) libpng$(MODEL) +$(OBJSL2)
+	$(LIB) libpng$(MODEL) +$(OBJSL3)
+
+pngtest$(E): pngtest$(O) libpng$(MODEL).lib
+	$(LD) $(LDFLAGS) pngtest.obj libpng$(MODEL).lib zlib_$(MODEL).lib
+
+# End of makefile for libpng
diff --git a/gs/libpng/scripts/makefile.vcawin32 b/gs/libpng/scripts/makefile.vcawin32
new file mode 100644
index 000000000..4c2f3cc0e
--- /dev/null
+++ b/gs/libpng/scripts/makefile.vcawin32
@@ -0,0 +1,103 @@
+# makefile for libpng
+# Copyright (C) 1998 Tim Wegner
+# For conditions of distribution and use, see copyright notice in png.h
+# Assumes that zlib.lib, zconf.h, and zlib.h have been copied to ..\zlib
+# To use, do "nmake /f scripts\makefile.vcawin32"
+
+# -------- Microsoft Visual C++ 5.0 and later, uses assembler code --------
+# If you don't want to use assembler (MMX) code, use makefile.vcwin32 instead.
+
+# Compiler, linker, librarian, and other tools
+CC = cl
+LD = link
+AR = lib
+CFLAGS  = -DPNG_USE_PNGVCRD -nologo -MD -O2 -W3 -I..\zlib
+LDFLAGS = -nologo
+ARFLAGS = -nologo
+RM = del
+
+# File extensions
+O=.obj
+
+#uncomment next to put error messages in a file
+#ERRFILE= >> pngerrs.log
+
+# Variables
+OBJS1 = png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O)
+OBJS2 = pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O)
+OBJS3 = pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
+OBJS4 = pngvcrd$(O)
+OBJS  = $(OBJS1) $(OBJS2) $(OBJS3) $(OBJS4)
+
+# Targets
+all: libpng.lib
+
+png$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngset$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngread$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngpread$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrtran$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrutil$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngerror$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngmem$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngtest$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngtrans$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwrite$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwtran$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwutil$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngvcrd$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+libpng.lib: $(OBJS)
+	-$(RM) $@
+	$(AR) $(ARFLAGS) -out:$@ $(OBJS) $(ERRFILE)
+
+pngtest.exe: pngtest$(O) libpng.lib
+	$(LD) $(LDFLAGS) -out:$@ pngtest$(O) libpng.lib ..\zlib\zlib.lib $(ERRFILE)
+
+test: pngtest.exe
+	pngtest
+
+clean:
+	-$(RM) *$(O)
+	-$(RM) libpng.lib
+	-$(RM) pngtest.exe
+	-$(RM) pngout.png
+
+# End of makefile for libpng
+
diff --git a/gs/libpng/scripts/makefile.vcwin32 b/gs/libpng/scripts/makefile.vcwin32
new file mode 100644
index 000000000..d23d81296
--- /dev/null
+++ b/gs/libpng/scripts/makefile.vcwin32
@@ -0,0 +1,99 @@
+# makefile for libpng
+# Copyright (C) 1998 Tim Wegner
+# For conditions of distribution and use, see copyright notice in png.h
+# Assumes that zlib.lib, zconf.h, and zlib.h have been copied to ..\zlib
+# To use, do "nmake /f scripts\makefile.vcwin32"
+
+# -------- Microsoft Visual C++ 2.0 and later, no assembler code --------
+# If you want to use assembler (MMX) code, use makefile.vcawin32 instead.
+
+# Compiler, linker, librarian, and other tools
+CC = cl
+LD = link
+AR = lib
+CFLAGS  = -nologo -MD -O2 -W3 -I..\zlib
+LDFLAGS = -nologo
+ARFLAGS = -nologo
+RM = del
+
+# File extensions
+O=.obj
+
+#uncomment next to put error messages in a file
+#ERRFILE= >> pngerrs.log
+
+# Variables
+OBJS1 = png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O)
+OBJS2 = pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O)
+OBJS3 = pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
+OBJS  = $(OBJS1) $(OBJS2) $(OBJS3)
+
+# Targets
+all: libpng.lib
+
+png$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngset$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngread$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngpread$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrtran$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrutil$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngerror$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngmem$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngtest$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngtrans$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwrite$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwtran$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwutil$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+libpng.lib: $(OBJS)
+	-$(RM) $@
+	$(AR) $(ARFLAGS) -out:$@ $(OBJS) $(ERRFILE)
+
+pngtest.exe: pngtest$(O) libpng.lib
+	$(LD) $(LDFLAGS) -out:$@ pngtest$(O) libpng.lib ..\zlib\zlib.lib $(ERRFILE)
+
+test: pngtest.exe
+	pngtest
+
+clean:
+	-$(RM) *$(O)
+	-$(RM) libpng.lib
+	-$(RM) pngtest.exe
+	-$(RM) pngout.png
+
+# End of makefile for libpng
+
diff --git a/gs/libpng/scripts/makefile.watcom b/gs/libpng/scripts/makefile.watcom
new file mode 100644
index 000000000..5e860fc06
--- /dev/null
+++ b/gs/libpng/scripts/makefile.watcom
@@ -0,0 +1,109 @@
+# Makefile for libpng
+# Watcom C/C++ 10.0 and later, 32-bit protected mode, flat memory model
+
+# Copyright (C) 2000, Pawel Mrochen, based on makefile.msc which is
+# copyright 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# To use, do "wmake /f scripts\makefile.watcom"
+
+
+# ---------------------- Watcom C/C++ 10.0 and later -----------------------
+
+# Where the zlib library and include files are located
+ZLIBLIB=..\zlib
+ZLIBINC=..\zlib
+
+# Target OS
+OS=DOS
+#OS=NT
+
+# Target CPU
+CPU=6		# Pentium Pro
+#CPU=5		# Pentium
+
+# Calling convention
+CALLING=r	# registers
+#CALLING=s	# stack
+
+# Uncomment next to put error messages in a file
+#ERRFILE=>>pngerrs
+
+# --------------------------------------------------------------------------
+
+
+CC=wcc386
+CFLAGS=-$(CPU)$(CALLING) -fp$(CPU) -fpi87 -oneatx -mf -bt=$(OS) -i=$(ZLIBINC) -zq
+LD=wcl386
+LDFLAGS=-zq
+
+O=.obj
+
+OBJS1=png$(O) pngset$(O) pngget$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O)
+OBJS2=pngmem$(O) pngpread$(O) pngread$(O) pngerror$(O) pngwrite$(O)
+OBJS3=pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O)
+
+
+all: test
+
+png$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngset$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngread$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngpread$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrtran$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrutil$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngerror$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngmem$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrio$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwio$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngtest$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngtrans$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwrite$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwtran$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwutil$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+libpng.lib: $(OBJS1) $(OBJS2) $(OBJS3)
+	wlib -b -c -n -q libpng.lib $(OBJS1)
+	wlib -b -c -q libpng.lib $(OBJS2)
+	wlib -b -c -q libpng.lib $(OBJS3)
+
+pngtest.exe: pngtest.obj libpng.lib
+	$(LD) $(LDFLAGS) pngtest.obj libpng.lib $(ZLIBLIB)\zlib.lib
+
+test: pngtest.exe .symbolic
+	pngtest.exe
+
+
+# End of makefile for libpng
diff --git a/gs/libpng/scripts/makevms.com b/gs/libpng/scripts/makevms.com
new file mode 100644
index 000000000..b9e389555
--- /dev/null
+++ b/gs/libpng/scripts/makevms.com
@@ -0,0 +1,144 @@
+$! make libpng under VMS
+$!
+$!
+$! Check for MMK/MMS
+$!
+$! This procedure accepts one parameter (contrib), which causes it to build
+$! the programs from the contrib directory instead of libpng.
+$!
+$ p1 = f$edit(p1,"UPCASE")
+$ if p1 .eqs. "CONTRIB"
+$ then
+$   set def [.contrib.gregbook]
+$   @makevms
+$   set def [-.pngminus]
+$   @makevms
+$   set def [--]
+$   exit
+$ endif
+$ Make = ""
+$ If F$Search ("Sys$System:MMS.EXE") .nes. "" Then Make = "MMS"
+$ If F$Type (MMK) .eqs. "STRING" Then Make = "MMK"
+$!
+$! Look for the compiler used
+$!
+$ zlibsrc = "[-.zlib]"
+$ ccopt="/include=''zlibsrc'"
+$ if f$getsyi("HW_MODEL").ge.1024
+$ then
+$  ccopt = "/prefix=all"+ccopt
+$  comp  = "__decc__=1"
+$  if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$ else
+$  if f$search("SYS$SYSTEM:DECC$COMPILER.EXE").eqs.""
+$   then
+$    if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$    if f$search("SYS$SYSTEM:VAXC.EXE").eqs.""
+$     then
+$      comp  = "__gcc__=1"
+$      CC :== GCC
+$     else
+$      comp = "__vaxc__=1"
+$     endif
+$   else
+$    if f$trnlnm("SYS").eqs."" then define sys decc$library_include:
+$    ccopt = "/decc/prefix=all"+ccopt
+$    comp  = "__decc__=1"
+$  endif
+$ endif
+$!
+$! Build the thing plain or with mms/mmk
+$!
+$ write sys$output "Compiling Libpng sources ..."
+$ if make.eqs.""
+$  then
+$   dele pngtest.obj;*
+$   CALL MAKE png.OBJ "cc ''CCOPT' png" -
+	png.c png.h pngconf.h
+$   CALL MAKE pngpread.OBJ "cc ''CCOPT' pngpread" -
+					 pngpread.c png.h pngconf.h
+$   CALL MAKE pngset.OBJ "cc ''CCOPT' pngset" -
+	pngset.c png.h pngconf.h
+$   CALL MAKE pngget.OBJ "cc ''CCOPT' pngget" -
+	pngget.c png.h pngconf.h
+$   CALL MAKE pngread.OBJ "cc ''CCOPT' pngread" -
+	pngread.c png.h pngconf.h
+$   CALL MAKE pngpread.OBJ "cc ''CCOPT' pngpread" -
+					 pngpread.c png.h pngconf.h
+$   CALL MAKE pngrtran.OBJ "cc ''CCOPT' pngrtran" -
+	pngrtran.c png.h pngconf.h
+$   CALL MAKE pngrutil.OBJ "cc ''CCOPT' pngrutil" -
+	pngrutil.c png.h pngconf.h
+$   CALL MAKE pngerror.OBJ "cc ''CCOPT' pngerror" -
+	pngerror.c png.h pngconf.h
+$   CALL MAKE pngmem.OBJ "cc ''CCOPT' pngmem" -
+	pngmem.c png.h pngconf.h
+$   CALL MAKE pngrio.OBJ "cc ''CCOPT' pngrio" -
+	pngrio.c png.h pngconf.h
+$   CALL MAKE pngwio.OBJ "cc ''CCOPT' pngwio" -
+	pngwio.c png.h pngconf.h
+$   CALL MAKE pngtrans.OBJ "cc ''CCOPT' pngtrans" -
+	pngtrans.c png.h pngconf.h
+$   CALL MAKE pngwrite.OBJ "cc ''CCOPT' pngwrite" -
+	pngwrite.c png.h pngconf.h
+$   CALL MAKE pngwtran.OBJ "cc ''CCOPT' pngwtran" -
+	pngwtran.c png.h pngconf.h
+$   CALL MAKE pngwutil.OBJ "cc ''CCOPT' pngwutil" -
+	pngwutil.c png.h pngconf.h
+$   write sys$output "Building Libpng ..."
+$   CALL MAKE libpng.OLB "lib/crea libpng.olb *.obj" *.OBJ
+$   write sys$output "Building pngtest..."
+$   CALL MAKE pngtest.OBJ "cc ''CCOPT' pngtest" -
+	pngtest.c png.h pngconf.h
+$   call make pngtest.exe -
+	"LINK pngtest,libpng.olb/lib,''zlibsrc'libz.olb/lib" -
+	pngtest.obj libpng.olb
+$   write sys$output "Testing Libpng..."
+$   run pngtest
+$  else
+$   if f$search("DESCRIP.MMS") .eqs. "" then copy/nolog [.SCRIPTS]DESCRIP.MMS []
+$   'make'/macro=('comp',zlibsrc='zlibsrc')
+$  endif
+$ write sys$output "Libpng build completed"
+$ exit
+$!
+$!
+$MAKE: SUBROUTINE   !SUBROUTINE TO CHECK DEPENDENCIES
+$ V = 'F$Verify(0)
+$! P1 = What we are trying to make
+$! P2 = Command to make it
+$! P3 - P8  What it depends on
+$
+$ If F$Search(P1) .Eqs. "" Then Goto Makeit
+$ Time = F$CvTime(F$File(P1,"RDT"))
+$arg=3
+$Loop:
+$       Argument = P'arg
+$       If Argument .Eqs. "" Then Goto Exit
+$       El=0
+$Loop2:
+$       File = F$Element(El," ",Argument)
+$       If File .Eqs. " " Then Goto Endl
+$       AFile = ""
+$Loop3:
+$       OFile = AFile
+$       AFile = F$Search(File)
+$       If AFile .Eqs. "" .Or. AFile .Eqs. OFile Then Goto NextEl
+$       If F$CvTime(F$File(AFile,"RDT")) .Ges. Time Then Goto Makeit
+$       Goto Loop3
+$NextEL:
+$       El = El + 1
+$       Goto Loop2
+$EndL:
+$ arg=arg+1
+$ If arg .Le. 8 Then Goto Loop
+$ Goto Exit
+$
+$Makeit:
+$ VV=F$VERIFY(0)
+$ write sys$output P2
+$ 'P2
+$ VV='F$Verify(VV)
+$Exit:
+$ If V Then Set Verify
+$ENDSUBROUTINE
diff --git a/gs/libpng/scripts/pngos2.def b/gs/libpng/scripts/pngos2.def
new file mode 100644
index 000000000..9aa61351f
--- /dev/null
+++ b/gs/libpng/scripts/pngos2.def
@@ -0,0 +1,248 @@
+;----------------------------------------
+; PNG.LIB module definition file for OS/2
+;----------------------------------------
+
+; Version 1.2.8
+
+LIBRARY		PNG
+DESCRIPTION	"PNG image compression library for OS/2"
+CODE		PRELOAD MOVEABLE DISCARDABLE
+DATA		PRELOAD MOVEABLE MULTIPLE
+
+EXPORTS
+
+
+  png_build_grayscale_palette
+  png_check_sig
+  png_chunk_error
+  png_chunk_warning
+  png_convert_from_struct_tm
+  png_convert_from_time_t
+  png_create_info_struct
+  png_create_read_struct
+  png_create_write_struct
+  png_data_freer
+  png_destroy_info_struct
+  png_destroy_read_struct
+  png_destroy_write_struct
+  png_error
+  png_free
+  png_free_data
+  png_get_IHDR
+  png_get_PLTE
+  png_get_bKGD
+  png_get_bit_depth
+  png_get_cHRM
+  png_get_cHRM_fixed
+  png_get_channels
+  png_get_color_type
+  png_get_compression_buffer_size
+  png_get_compression_type
+  png_get_copyright
+  png_get_error_ptr
+  png_get_filter_type
+  png_get_gAMA
+  png_get_gAMA_fixed
+  png_get_hIST
+  png_get_header_ver
+  png_get_header_version
+  png_get_iCCP
+  png_get_image_height
+  png_get_image_width
+  png_get_interlace_type
+  png_get_io_ptr
+  png_get_libpng_ver
+  png_get_oFFs
+  png_get_pCAL
+  png_get_pHYs
+  png_get_pixel_aspect_ratio
+  png_get_pixels_per_meter
+  png_get_progressive_ptr
+  png_get_rgb_to_gray_status
+  png_get_rowbytes
+  png_get_rows
+  png_get_sBIT
+  png_get_sCAL
+  png_get_sPLT
+  png_get_sRGB
+  png_get_signature
+  png_get_tIME
+  png_get_tRNS
+  png_get_text
+  png_get_unknown_chunks
+  png_get_user_chunk_ptr
+  png_get_user_transform_ptr
+  png_get_valid
+  png_get_x_offset_microns
+  png_get_x_offset_pixels
+  png_get_x_pixels_per_meter
+  png_get_y_offset_microns
+  png_get_y_offset_pixels
+  png_get_y_pixels_per_meter
+  png_malloc
+  png_memcpy_check
+  png_memset_check
+  png_permit_empty_plte
+  png_process_data
+  png_progressive_combine_row
+  png_read_end
+  png_read_image
+  png_read_info
+  png_read_init ; deprecated
+  png_read_png
+  png_read_row
+  png_read_rows
+  png_read_update_info
+  png_reset_zstream
+  png_set_IHDR
+  png_set_PLTE
+  png_set_bKGD
+  png_set_background
+  png_set_bgr
+  png_set_cHRM
+  png_set_cHRM_fixed
+  png_set_compression_buffer_size
+  png_set_compression_level
+  png_set_compression_mem_level
+  png_set_compression_method
+  png_set_compression_strategy
+  png_set_compression_window_bits
+  png_set_crc_action
+  png_set_dither
+  png_set_error_fn
+  png_set_expand
+  png_set_filler
+  png_set_filter
+  png_set_filter_heuristics
+  png_set_flush
+  png_set_gAMA
+  png_set_gAMA_fixed
+  png_set_gamma
+  png_set_gray_1_2_4_to_8
+  png_set_gray_to_rgb
+  png_set_hIST
+  png_set_iCCP
+  png_set_interlace_handling
+  png_set_invert_alpha
+  png_set_invert_mono
+  png_set_keep_unknown_chunks
+  png_set_oFFs
+  png_set_pCAL
+  png_set_pHYs
+  png_set_packing
+  png_set_packswap
+  png_set_palette_to_rgb
+  png_set_progressive_read_fn
+  png_set_read_fn
+  png_set_read_status_fn
+  png_set_read_user_chunk_fn
+  png_set_read_user_transform_fn
+  png_set_rgb_to_gray
+  png_set_rgb_to_gray_fixed
+  png_set_rows
+  png_set_sBIT
+  png_set_sCAL
+  png_set_sPLT
+  png_set_sRGB
+  png_set_sRGB_gAMA_and_cHRM
+  png_set_shift
+  png_set_sig_bytes
+  png_set_strip_16
+  png_set_strip_alpha
+  png_set_swap
+  png_set_swap_alpha
+  png_set_tIME
+  png_set_tRNS
+  png_set_tRNS_to_alpha
+  png_set_text
+  png_set_unknown_chunk_location
+  png_set_unknown_chunks
+  png_set_user_transform_info
+  png_set_write_fn
+  png_set_write_status_fn
+  png_set_write_user_transform_fn
+  png_sig_cmp
+  png_start_read_image
+  png_warning
+  png_write_chunk
+  png_write_chunk_data
+  png_write_chunk_end
+  png_write_chunk_start
+  png_write_end
+  png_write_flush
+  png_write_image
+  png_write_info
+  png_write_info_before_PLTE
+  png_write_init ; deprecated
+  png_write_png
+  png_write_row
+  png_write_rows
+  png_read_init_2
+  png_write_init_2
+  png_access_version_number
+  png_init_io
+  png_convert_to_rfc1123
+  png_set_invalid
+
+; Added at version 1.2.0:
+  png_mmx_support
+  png_permit_empty_plte
+  png_permit_mng_features
+  png_get_mmx_flagmask
+  png_get_asm_flagmask
+  png_get_asm_flags
+  png_get_mmx_bitdepth_threshold
+  png_get_mmx_rowbytes_threshold
+  png_set_asm_flags
+  png_init_mmx_flags
+
+; Added at version 1.2.2:
+  png_handle_as_unknown
+
+; Added at version 1.2.2 and deleted from 1.2.3:
+; png_zalloc
+; png_zfree
+
+; Added at version 1.2.4
+  png_malloc_warn
+
+; Added at version 1.2.6
+  png_set_user_limits
+  png_get_user_height_max
+  png_get_user_width_max
+; Added at version 1.2.7
+  png_set_add_alpha
+
+; These are not present when libpng is compiled with PNG_NO_GLOBAL_ARRAYS
+  png_libpng_ver
+  png_pass_start
+  png_pass_inc
+  png_pass_ystart
+  png_pass_yinc
+  png_pass_mask
+  png_pass_dsp_mask
+; png_pass_width
+; png_pass_height
+
+; These are not present when libpng is compiled with PNG_NO_GLOBAL_ARRAYS
+  png_IHDR
+  png_IDAT
+  png_IEND
+  png_PLTE
+  png_bKGD
+  png_cHRM
+  png_gAMA
+  png_hIST
+  png_iCCP
+  png_iTXt
+  png_oFFs
+  png_pCAL
+  png_pHYs
+  png_sBIT
+  png_sCAL
+  png_sPLT
+  png_sRGB
+  png_tEXt
+  png_tIME
+  png_tRNS
+  png_zTXt
diff --git a/gs/libpng/scripts/pngw32.def b/gs/libpng/scripts/pngw32.def
new file mode 100644
index 000000000..8303bfeb7
--- /dev/null
+++ b/gs/libpng/scripts/pngw32.def
@@ -0,0 +1,226 @@
+;------------------------------------------
+; LIBPNG module definition file for Windows
+;------------------------------------------
+
+LIBRARY
+
+EXPORTS
+;Version 1.2.8
+  png_build_grayscale_palette  @1
+  png_check_sig        @2
+  png_chunk_error      @3
+  png_chunk_warning      @4
+  png_convert_from_struct_tm   @5
+  png_convert_from_time_t    @6
+  png_create_info_struct     @7
+  png_create_read_struct     @8
+  png_create_write_struct    @9
+  png_data_freer    @10
+  png_destroy_info_struct  @11
+  png_destroy_read_struct  @12
+  png_destroy_write_struct  @13
+  png_error    @14
+  png_free      @15
+  png_free_data    @16
+  png_get_IHDR    @17
+  png_get_PLTE    @18
+  png_get_bKGD    @19
+  png_get_bit_depth    @20
+  png_get_cHRM    @21
+  png_get_cHRM_fixed  @22
+  png_get_channels    @23
+  png_get_color_type  @24
+  png_get_compression_buffer_size  @25
+  png_get_compression_type  @26
+  png_get_copyright    @27
+  png_get_error_ptr    @28
+  png_get_filter_type  @29
+  png_get_gAMA    @30
+  png_get_gAMA_fixed  @31
+  png_get_hIST    @32
+  png_get_header_ver  @33
+  png_get_header_version  @34
+  png_get_iCCP    @35
+  png_get_image_height  @36
+  png_get_image_width  @37
+  png_get_interlace_type  @38
+  png_get_io_ptr    @39
+  png_get_libpng_ver  @40
+  png_get_oFFs    @41
+  png_get_pCAL    @42
+  png_get_pHYs    @43
+  png_get_pixel_aspect_ratio  @44
+  png_get_pixels_per_meter  @45
+  png_get_progressive_ptr  @46
+  png_get_rgb_to_gray_status  @47
+  png_get_rowbytes    @48
+  png_get_rows    @49
+  png_get_sBIT    @50
+  png_get_sCAL    @51
+  png_get_sPLT    @52
+  png_get_sRGB    @53
+  png_get_signature    @54
+  png_get_tIME    @55
+  png_get_tRNS    @56
+  png_get_text    @57
+  png_get_unknown_chunks  @58
+  png_get_user_chunk_ptr  @59
+  png_get_user_transform_ptr  @60
+  png_get_valid    @61
+  png_get_x_offset_microns  @62
+  png_get_x_offset_pixels  @63
+  png_get_x_pixels_per_meter  @64
+  png_get_y_offset_microns  @65
+  png_get_y_offset_pixels  @66
+  png_get_y_pixels_per_meter  @67
+  png_malloc    @68
+  png_memcpy_check    @69
+  png_memset_check    @70
+; png_permit_empty_plte is deprecated
+  png_permit_empty_plte  @71
+  png_process_data    @72
+  png_progressive_combine_row  @73
+  png_read_end    @74
+  png_read_image    @75
+  png_read_info    @76
+; png_read_init is deprecated
+  png_read_init    @77
+  png_read_png    @78
+  png_read_row    @79
+  png_read_rows    @80
+  png_read_update_info  @81
+  png_reset_zstream    @82
+  png_set_IHDR    @83
+  png_set_PLTE    @84
+  png_set_bKGD    @85
+  png_set_background  @86
+  png_set_bgr    @87
+  png_set_cHRM    @88
+  png_set_cHRM_fixed  @89
+  png_set_compression_buffer_size  @90
+  png_set_compression_level  @91
+  png_set_compression_mem_level  @92
+  png_set_compression_method  @93
+  png_set_compression_strategy  @94
+  png_set_compression_window_bits  @95
+  png_set_crc_action  @96
+  png_set_dither    @97
+  png_set_error_fn    @98
+  png_set_expand    @99
+  png_set_filler    @100
+  png_set_filter    @101
+  png_set_filter_heuristics  @102
+  png_set_flush    @103
+  png_set_gAMA    @104
+  png_set_gAMA_fixed  @105
+  png_set_gamma    @106
+  png_set_gray_1_2_4_to_8  @107
+  png_set_gray_to_rgb  @108
+  png_set_hIST    @109
+  png_set_iCCP    @110
+  png_set_interlace_handling  @111
+  png_set_invert_alpha  @112
+  png_set_invert_mono  @113
+  png_set_keep_unknown_chunks  @114
+  png_set_oFFs    @115
+  png_set_pCAL    @116
+  png_set_pHYs    @117
+  png_set_packing    @118
+  png_set_packswap    @119
+  png_set_palette_to_rgb  @120
+  png_set_progressive_read_fn  @121
+  png_set_read_fn    @122
+  png_set_read_status_fn  @123
+  png_set_read_user_chunk_fn  @124
+  png_set_read_user_transform_fn  @125
+  png_set_rgb_to_gray  @126
+  png_set_rgb_to_gray_fixed  @127
+  png_set_rows    @128
+  png_set_sBIT    @129
+  png_set_sCAL    @130
+  png_set_sPLT    @131
+  png_set_sRGB    @132
+  png_set_sRGB_gAMA_and_cHRM  @133
+  png_set_shift    @134
+  png_set_sig_bytes    @135
+  png_set_strip_16    @136
+  png_set_strip_alpha  @137
+  png_set_swap    @138
+  png_set_swap_alpha  @139
+  png_set_tIME    @140
+  png_set_tRNS    @141
+  png_set_tRNS_to_alpha  @142
+  png_set_text    @143
+  png_set_unknown_chunk_location  @144
+  png_set_unknown_chunks  @145
+  png_set_user_transform_info  @146
+  png_set_write_fn    @147
+  png_set_write_status_fn  @148
+  png_set_write_user_transform_fn  @149
+  png_sig_cmp    @150
+  png_start_read_image  @151
+  png_warning    @152
+  png_write_chunk    @153
+  png_write_chunk_data  @154
+  png_write_chunk_end  @155
+  png_write_chunk_start  @156
+  png_write_end    @157
+  png_write_flush    @158
+  png_write_image    @159
+  png_write_info    @160
+  png_write_info_before_PLTE  @161
+; png_write_init is deprecated
+  png_write_init    @162
+  png_write_png    @163
+  png_write_row    @164
+  png_write_rows    @165
+; png_read_init_2 and png_write_init_2 are deprecated.
+  png_read_init_2    @166
+  png_write_init_2    @167
+  png_access_version_number  @168
+;  png_sig_bytes    @169
+;  png_libpng_ver    @170
+  png_init_io    @171
+  png_convert_to_rfc1123     @172
+  png_set_invalid  @173
+; Added at version 1.0.12
+; For compatiblity with 1.0.7-1.0.11
+  png_info_init @174
+  png_read_init_3    @175
+  png_write_init_3    @176
+  png_info_init_3 @177
+  png_destroy_struct  @178
+; Added at version 1.2.0
+; For use with PNG_USER_MEM_SUPPORTED
+  png_destroy_struct_2  @179
+  png_create_read_struct_2 @180
+  png_create_write_struct_2 @181
+  png_malloc_default @182
+  png_free_default @183
+; MNG features
+  png_permit_mng_features  @184
+; MMX support
+  png_mmx_support  @185
+  png_get_mmx_flagmask  @186
+  png_get_asm_flagmask  @187
+  png_get_asm_flags  @188
+  png_get_mmx_bitdepth_threshold  @189
+  png_get_mmx_rowbytes_threshold  @190
+  png_set_asm_flags  @191
+  png_init_mmx_flags  @192
+; Strip error numbers
+  png_set_strip_error_numbers @193
+; Added at version 1.2.2
+  png_handle_as_unknown @194
+; Added at version 1.2.2 and deleted from 1.2.3
+; png_zalloc @195
+; png_zfree @196
+; Added at version 1.2.4
+  png_malloc_warn @195
+; Added at version 1.2.6
+  png_malloc_warn @195
+  png_get_user_height_max @196
+  png_get_user_width_max @197
+  png_set_user_limits @198
+; Added at version 1.2.7
+  png_set_add_alpha @199
diff --git a/gs/libpng/scripts/pngw32.rc b/gs/libpng/scripts/pngw32.rc
new file mode 100644
index 000000000..02e30e299
--- /dev/null
+++ b/gs/libpng/scripts/pngw32.rc
@@ -0,0 +1,112 @@
+#define PNG_VERSION_INFO_ONLY
+
+#include <windows.h>
+#include "../png.h"
+
+#define _QUOTE(x) # x
+#define QUOTE(x) _QUOTE(x)
+
+#define PNG_LIBPNG_DLLFNAME "LIBPNG"
+
+/* Support deprecated PRIVATEBUILD macro */
+#if defined(PRIVATEBUILD) && !defined(PNG_USER_PRIVATEBUILD)
+#  define PNG_USER_PRIVATEBUILD PRIVATEBUILD
+#endif
+
+#if defined(PNG_USER_DLLFNAME_POSTFIX) && !defined(PNG_USER_PRIVATEBUILD)
+#  error "PNG_USER_PRIVATEBUILD must be defined as a string describing the\
+ custom changes made to the library."
+#endif
+
+/* Prioritize PNG_USER_x over PNG_LIBPNG_x */
+#ifdef PNG_USER_DLLFNAME_POSTFIX
+#  undef PNG_LIBPNG_DLLFNAME_POSTFIX
+#  define PNG_LIBPNG_DLLFNAME_POSTFIX PNG_USER_DLLFNAME_POSTFIX
+#endif
+
+#ifdef PNG_USER_VERSIONINFO_COMMENTS
+#  undef PNG_LIBPNG_VERSIONINFO_COMMENTS
+#  define PNG_LIBPNG_VERSIONINFO_COMMENTS PNG_USER_VERSIONINFO_COMMENTS
+#endif
+
+#if defined(PNG_DEBUG) && (PNG_DEBUG > 0)
+#  define VS_DEBUG VS_FF_DEBUG
+#  ifndef PNG_LIBPNG_DLLFNAME_POSTFIX
+#    define PNG_LIBPNG_DLLFNAME_POSTFIX "D"
+#  endif /* PNG_LIBPNG_DLLFNAME_POSTFIX */
+#  ifndef PNG_LIBPNG_VERSIONINFO_COMMENTS
+#    define PNG_LIBPNG_VERSIONINFO_COMMENTS "PNG_DEBUG=" QUOTE(PNG_DEBUG)
+#  endif /* PNG_LIBPNG_VERSIONINFO_COMMENTS */
+#else
+#  define VS_DEBUG 0
+#  ifndef PNG_LIBPNG_DLLFNAME_POSTFIX
+#     define PNG_LIBPNG_DLLFNAME_POSTFIX
+#  endif /* PNG_LIBPNG_DLLFNAME_POSTFIX */
+#endif /* defined(DEBUG)... */
+
+#ifdef PNG_USER_PRIVATEBUILD
+#  define VS_PRIVATEBUILD VS_FF_PRIVATEBUILD
+#else
+#  define VS_PRIVATEBUILD 0
+#endif /* PNG_USER_PRIVATEBUILD */
+
+#ifdef PNG_LIBPNG_SPECIALBUILD
+#  define VS_SPECIALBUILD VS_FF_SPECIALBUILD
+#else
+#  define VS_SPECIALBUILD 0
+#endif /* PNG_LIBPNG_BUILD_SPECIAL */
+
+#if ((PNG_LIBPNG_BUILD_BASE_TYPE & PNG_LIBPNG_RELEASE_STATUS_MASK) !=\
+      PNG_LIBPNG_BUILD_STABLE)
+#  define VS_PRERELEASE VS_FF_PRERELEASE
+#  define VS_PATCHED 0
+#else
+#  define VS_PRERELEASE 0
+#  if (PNG_LIBPNG_BUILD_BASE_TYPE & PNG_LIBPNG_BUILD_PATCHED)
+#    define VS_PATCHED VS_FF_PATCHED
+#  else
+#    define VS_PATCHED 0
+#  endif
+#endif
+
+VS_VERSION_INFO VERSIONINFO
+FILEVERSION PNG_LIBPNG_VER_MAJOR, PNG_LIBPNG_VER_MINOR, PNG_LIBPNG_VER_RELEASE, PNG_LIBPNG_VER_BUILD
+PRODUCTVERSION PNG_LIBPNG_VER_MAJOR, PNG_LIBPNG_VER_MINOR, PNG_LIBPNG_VER_RELEASE, PNG_LIBPNG_VER_BUILD
+FILEFLAGSMASK VS_FFI_FILEFLAGSMASK
+FILEFLAGS VS_DEBUG | VS_PRIVATEBUILD | VS_SPECIALBUILD | VS_PRERELEASE | VS_PATCHED
+FILEOS VOS__WINDOWS32
+FILETYPE VFT_DLL
+FILESUBTYPE VFT2_UNKNOWN
+BEGIN
+  BLOCK "StringFileInfo"
+  BEGIN BLOCK "040904E4" /* Language type = U.S English(0x0409) and Character Set = Windows, Multilingual(0x04E4) */
+    BEGIN
+#ifdef PNG_LIBPNG_VERSIONINFO_COMMENTS
+      VALUE "Comments", PNG_LIBPNG_VERSIONINFO_COMMENTS "\000"
+#endif /* PNG_LIBPNG_VERSIONINFO_COMMENTS */
+#ifdef PNG_USER_VERSIONINFO_COMPANYNAME
+      VALUE "CompanyName", PNG_USER_VERSIONINFO_COMPANYNAME "\000"
+#endif /* PNG_USER_VERSIONINFO_COMPANYNAME */
+      VALUE "FileDescription", "PNG image compression library\000"
+      VALUE "FileVersion", PNG_LIBPNG_VER_STRING "\000"
+      VALUE "InternalName", PNG_LIBPNG_DLLFNAME QUOTE(PNG_LIBPNG_VER_DLLNUM) PNG_LIBPNG_DLLFNAME_POSTFIX " (Windows 32 bit)\000"
+      VALUE "LegalCopyright", "\251 1998-2004 Glenn Randers-Pehrson et al.\000"
+#ifdef PNG_USER_VERSIONINFO_LEGALTRADEMARKS
+      VALUE "LegalTrademarks", PNG_USER_VERSIONINFO_LEGALTRADEMARKS "\000"
+#endif /* PNG_USER_VERSIONINFO_LEGALTRADEMARKS */
+      VALUE "OriginalFilename", PNG_LIBPNG_DLLFNAME QUOTE(PNG_LIBPNG_VER_DLLNUM) PNG_LIBPNG_DLLFNAME_POSTFIX ".DLL\000"
+#ifdef PNG_USER_PRIVATEBUILD
+      VALUE "PrivateBuild", PNG_USER_PRIVATEBUILD "\000"
+#endif /* PNG_USER_PRIVATEBUILD */
+      VALUE "ProductName", "LibPNG\000"
+      VALUE "ProductVersion", "1\000"
+#ifdef PNG_LIBPNG_SPECIALBUILD
+      VALUE "SpecialBuild", PNG_LIBPNG_SPECIALBUILD "\000"
+#endif /* PNG_LIBPNG_SPECIALBUILD */
+    END
+  END
+  BLOCK "VarFileInfo"
+  BEGIN
+    VALUE "Translation", 0x0409, 0x04E4
+  END
+END
diff --git a/gs/libpng/scripts/smakefile.ppc b/gs/libpng/scripts/smakefile.ppc
new file mode 100644
index 000000000..e5c027841
--- /dev/null
+++ b/gs/libpng/scripts/smakefile.ppc
@@ -0,0 +1,30 @@
+# Amiga powerUP (TM) Makefile
+# makefile for libpng and SAS C V6.58/7.00 PPC compiler
+# Copyright (C) 1998 by Andreas R. Kleinert
+# For conditions of distribution and use, see copyright notice in png.h
+
+CC       = scppc
+CFLAGS   = NOSTKCHK NOSINT OPTIMIZE OPTGO OPTPEEP OPTINLOCAL OPTINL IDIR /zlib \
+           OPTLOOP OPTRDEP=8 OPTDEP=8 OPTCOMP=8
+LIBNAME  = libpng.a
+AR       = ppc-amigaos-ar
+AR_FLAGS = cr
+RANLIB   = ppc-amigaos-ranlib
+LDFLAGS  = -r -o
+LDLIBS   =  ../zlib/libzip.a LIB:scppc.a
+LN       = ppc-amigaos-ld
+RM       = delete quiet
+MKDIR    = makedir
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o pngread.o \
+pngerror.o pngpread.o pngwrite.o pngrtran.o pngwtran.o pngrio.o pngwio.o pngmem.o
+
+all: $(LIBNAME) pngtest
+
+$(LIBNAME): $(OBJS)
+            $(AR) $(AR_FLAGS) $@ $(OBJS)
+            $(RANLIB) $@
+
+pngtest: pngtest.o $(LIBNAME)
+        $(LN) $(LDFLAGS) pngtest LIB:c_ppc.o pngtest.o $(LIBNAME) $(LDLIBS) \
+LIB:end.o
diff --git a/gs/zlib/ChangeLog b/gs/zlib/ChangeLog
new file mode 100644
index 000000000..7f6869d32
--- /dev/null
+++ b/gs/zlib/ChangeLog
@@ -0,0 +1,855 @@
+
+                ChangeLog file for zlib
+
+Changes in 1.2.3 (18 July 2005)
+- Apply security vulnerability fixes to contrib/infback9 as well
+- Clean up some text files (carriage returns, trailing space)
+- Update testzlib, vstudio, masmx64, and masmx86 in contrib [Vollant]
+
+Changes in 1.2.2.4 (11 July 2005)
+- Add inflatePrime() function for starting inflation at bit boundary
+- Avoid some Visual C warnings in deflate.c
+- Avoid more silly Visual C warnings in inflate.c and inftrees.c for 64-bit
+  compile
+- Fix some spelling errors in comments [Betts]
+- Correct inflateInit2() error return documentation in zlib.h
+- Added zran.c example of compressed data random access to examples
+  directory, shows use of inflatePrime()
+- Fix cast for assignments to strm->state in inflate.c and infback.c
+- Fix zlibCompileFlags() in zutil.c to use 1L for long shifts [Oberhumer]
+- Move declarations of gf2 functions to right place in crc32.c [Oberhumer]
+- Add cast in trees.c t avoid a warning [Oberhumer]
+- Avoid some warnings in fitblk.c, gun.c, gzjoin.c in examples [Oberhumer]
+- Update make_vms.com [Zinser]
+- Initialize state->write in inflateReset() since copied in inflate_fast()
+- Be more strict on incomplete code sets in inflate_table() and increase
+  ENOUGH and MAXD -- this repairs a possible security vulnerability for
+  invalid inflate input.  Thanks to Tavis Ormandy and Markus Oberhumer for
+  discovering the vulnerability and providing test cases.
+- Add ia64 support to configure for HP-UX [Smith]
+- Add error return to gzread() for format or i/o error [Levin]
+- Use malloc.h for OS/2 [Necasek]
+
+Changes in 1.2.2.3 (27 May 2005)
+- Replace 1U constants in inflate.c and inftrees.c for 64-bit compile
+- Typecast fread() return values in gzio.c [Vollant]
+- Remove trailing space in minigzip.c outmode (VC++ can't deal with it)
+- Fix crc check bug in gzread() after gzungetc() [Heiner]
+- Add the deflateTune() function to adjust internal compression parameters
+- Add a fast gzip decompressor, gun.c, to examples (use of inflateBack)
+- Remove an incorrect assertion in examples/zpipe.c
+- Add C++ wrapper in infback9.h [Donais]
+- Fix bug in inflateCopy() when decoding fixed codes
+- Note in zlib.h how much deflateSetDictionary() actually uses
+- Remove USE_DICT_HEAD in deflate.c (would mess up inflate if used)
+- Add _WIN32_WCE to define WIN32 in zconf.in.h [Spencer]
+- Don't include stderr.h or errno.h for _WIN32_WCE in zutil.h [Spencer]
+- Add gzdirect() function to indicate transparent reads
+- Update contrib/minizip [Vollant]
+- Fix compilation of deflate.c when both ASMV and FASTEST [Oberhumer]
+- Add casts in crc32.c to avoid warnings [Oberhumer]
+- Add contrib/masmx64 [Vollant]
+- Update contrib/asm586, asm686, masmx86, testzlib, vstudio [Vollant]
+
+Changes in 1.2.2.2 (30 December 2004)
+- Replace structure assignments in deflate.c and inflate.c with zmemcpy to
+  avoid implicit memcpy calls (portability for no-library compilation)
+- Increase sprintf() buffer size in gzdopen() to allow for large numbers
+- Add INFLATE_STRICT to check distances against zlib header
+- Improve WinCE errno handling and comments [Chang]
+- Remove comment about no gzip header processing in FAQ
+- Add Z_FIXED strategy option to deflateInit2() to force fixed trees
+- Add updated make_vms.com [Coghlan], update README
+- Create a new "examples" directory, move gzappend.c there, add zpipe.c,
+  fitblk.c, gzlog.[ch], gzjoin.c, and zlib_how.html.
+- Add FAQ entry and comments in deflate.c on uninitialized memory access
+- Add Solaris 9 make options in configure [Gilbert]
+- Allow strerror() usage in gzio.c for STDC
+- Fix DecompressBuf in contrib/delphi/ZLib.pas [ManChesTer]
+- Update contrib/masmx86/inffas32.asm and gvmat32.asm [Vollant]
+- Use z_off_t for adler32_combine() and crc32_combine() lengths
+- Make adler32() much faster for small len
+- Use OS_CODE in deflate() default gzip header
+
+Changes in 1.2.2.1 (31 October 2004)
+- Allow inflateSetDictionary() call for raw inflate
+- Fix inflate header crc check bug for file names and comments
+- Add deflateSetHeader() and gz_header structure for custom gzip headers
+- Add inflateGetheader() to retrieve gzip headers
+- Add crc32_combine() and adler32_combine() functions
+- Add alloc_func, free_func, in_func, out_func to Z_PREFIX list
+- Use zstreamp consistently in zlib.h (inflate_back functions)
+- Remove GUNZIP condition from definition of inflate_mode in inflate.h
+  and in contrib/inflate86/inffast.S [Truta, Anderson]
+- Add support for AMD64 in contrib/inflate86/inffas86.c [Anderson]
+- Update projects/README.projects and projects/visualc6 [Truta]
+- Update win32/DLL_FAQ.txt [Truta]
+- Avoid warning under NO_GZCOMPRESS in gzio.c; fix typo [Truta]
+- Deprecate Z_ASCII; use Z_TEXT instead [Truta]
+- Use a new algorithm for setting strm->data_type in trees.c [Truta]
+- Do not define an exit() prototype in zutil.c unless DEBUG defined
+- Remove prototype of exit() from zutil.c, example.c, minigzip.c [Truta]
+- Add comment in zlib.h for Z_NO_FLUSH parameter to deflate()
+- Fix Darwin build version identification [Peterson]
+
+Changes in 1.2.2 (3 October 2004)
+- Update zlib.h comments on gzip in-memory processing
+- Set adler to 1 in inflateReset() to support Java test suite [Walles]
+- Add contrib/dotzlib [Ravn]
+- Update win32/DLL_FAQ.txt [Truta]
+- Update contrib/minizip [Vollant]
+- Move contrib/visual-basic.txt to old/ [Truta]
+- Fix assembler builds in projects/visualc6/ [Truta]
+
+Changes in 1.2.1.2 (9 September 2004)
+- Update INDEX file
+- Fix trees.c to update strm->data_type (no one ever noticed!)
+- Fix bug in error case in inflate.c, infback.c, and infback9.c [Brown]
+- Add "volatile" to crc table flag declaration (for DYNAMIC_CRC_TABLE)
+- Add limited multitasking protection to DYNAMIC_CRC_TABLE
+- Add NO_vsnprintf for VMS in zutil.h [Mozilla]
+- Don't declare strerror() under VMS [Mozilla]
+- Add comment to DYNAMIC_CRC_TABLE to use get_crc_table() to initialize
+- Update contrib/ada [Anisimkov]
+- Update contrib/minizip [Vollant]
+- Fix configure to not hardcode directories for Darwin [Peterson]
+- Fix gzio.c to not return error on empty files [Brown]
+- Fix indentation; update version in contrib/delphi/ZLib.pas and
+  contrib/pascal/zlibpas.pas [Truta]
+- Update mkasm.bat in contrib/masmx86 [Truta]
+- Update contrib/untgz [Truta]
+- Add projects/README.projects [Truta]
+- Add project for MS Visual C++ 6.0 in projects/visualc6 [Cadieux, Truta]
+- Update win32/DLL_FAQ.txt [Truta]
+- Update list of Z_PREFIX symbols in zconf.h [Randers-Pehrson, Truta]
+- Remove an unnecessary assignment to curr in inftrees.c [Truta]
+- Add OS/2 to exe builds in configure [Poltorak]
+- Remove err dummy parameter in zlib.h [Kientzle]
+
+Changes in 1.2.1.1 (9 January 2004)
+- Update email address in README
+- Several FAQ updates
+- Fix a big fat bug in inftrees.c that prevented decoding valid
+  dynamic blocks with only literals and no distance codes --
+  Thanks to "Hot Emu" for the bug report and sample file
+- Add a note to puff.c on no distance codes case.
+
+Changes in 1.2.1 (17 November 2003)
+- Remove a tab in contrib/gzappend/gzappend.c
+- Update some interfaces in contrib for new zlib functions
+- Update zlib version number in some contrib entries
+- Add Windows CE definition for ptrdiff_t in zutil.h [Mai, Truta]
+- Support shared libraries on Hurd and KFreeBSD [Brown]
+- Fix error in NO_DIVIDE option of adler32.c
+
+Changes in 1.2.0.8 (4 November 2003)
+- Update version in contrib/delphi/ZLib.pas and contrib/pascal/zlibpas.pas
+- Add experimental NO_DIVIDE #define in adler32.c
+    - Possibly faster on some processors (let me know if it is)
+- Correct Z_BLOCK to not return on first inflate call if no wrap
+- Fix strm->data_type on inflate() return to correctly indicate EOB
+- Add deflatePrime() function for appending in the middle of a byte
+- Add contrib/gzappend for an example of appending to a stream
+- Update win32/DLL_FAQ.txt [Truta]
+- Delete Turbo C comment in README [Truta]
+- Improve some indentation in zconf.h [Truta]
+- Fix infinite loop on bad input in configure script [Church]
+- Fix gzeof() for concatenated gzip files [Johnson]
+- Add example to contrib/visual-basic.txt [Michael B.]
+- Add -p to mkdir's in Makefile.in [vda]
+- Fix configure to properly detect presence or lack of printf functions
+- Add AS400 support [Monnerat]
+- Add a little Cygwin support [Wilson]
+
+Changes in 1.2.0.7 (21 September 2003)
+- Correct some debug formats in contrib/infback9
+- Cast a type in a debug statement in trees.c
+- Change search and replace delimiter in configure from % to # [Beebe]
+- Update contrib/untgz to 0.2 with various fixes [Truta]
+- Add build support for Amiga [Nikl]
+- Remove some directories in old that have been updated to 1.2
+- Add dylib building for Mac OS X in configure and Makefile.in
+- Remove old distribution stuff from Makefile
+- Update README to point to DLL_FAQ.txt, and add comment on Mac OS X
+- Update links in README
+
+Changes in 1.2.0.6 (13 September 2003)
+- Minor FAQ updates
+- Update contrib/minizip to 1.00 [Vollant]
+- Remove test of gz functions in example.c when GZ_COMPRESS defined [Truta]
+- Update POSTINC comment for 68060 [Nikl]
+- Add contrib/infback9 with deflate64 decoding (unsupported)
+- For MVS define NO_vsnprintf and undefine FAR [van Burik]
+- Add pragma for fdopen on MVS [van Burik]
+
+Changes in 1.2.0.5 (8 September 2003)
+- Add OF to inflateBackEnd() declaration in zlib.h
+- Remember start when using gzdopen in the middle of a file
+- Use internal off_t counters in gz* functions to properly handle seeks
+- Perform more rigorous check for distance-too-far in inffast.c
+- Add Z_BLOCK flush option to return from inflate at block boundary
+- Set strm->data_type on return from inflate
+    - Indicate bits unused, if at block boundary, and if in last block
+- Replace size_t with ptrdiff_t in crc32.c, and check for correct size
+- Add condition so old NO_DEFLATE define still works for compatibility
+- FAQ update regarding the Windows DLL [Truta]
+- INDEX update: add qnx entry, remove aix entry [Truta]
+- Install zlib.3 into mandir [Wilson]
+- Move contrib/zlib_dll_FAQ.txt to win32/DLL_FAQ.txt; update [Truta]
+- Adapt the zlib interface to the new DLL convention guidelines [Truta]
+- Introduce ZLIB_WINAPI macro to allow the export of functions using
+  the WINAPI calling convention, for Visual Basic [Vollant, Truta]
+- Update msdos and win32 scripts and makefiles [Truta]
+- Export symbols by name, not by ordinal, in win32/zlib.def [Truta]
+- Add contrib/ada [Anisimkov]
+- Move asm files from contrib/vstudio/vc70_32 to contrib/asm386 [Truta]
+- Rename contrib/asm386 to contrib/masmx86 [Truta, Vollant]
+- Add contrib/masm686 [Truta]
+- Fix offsets in contrib/inflate86 and contrib/masmx86/inffas32.asm
+  [Truta, Vollant]
+- Update contrib/delphi; rename to contrib/pascal; add example [Truta]
+- Remove contrib/delphi2; add a new contrib/delphi [Truta]
+- Avoid inclusion of the nonstandard <memory.h> in contrib/iostream,
+  and fix some method prototypes [Truta]
+- Fix the ZCR_SEED2 constant to avoid warnings in contrib/minizip
+  [Truta]
+- Avoid the use of backslash (\) in contrib/minizip [Vollant]
+- Fix file time handling in contrib/untgz; update makefiles [Truta]
+- Update contrib/vstudio/vc70_32 to comply with the new DLL guidelines
+  [Vollant]
+- Remove contrib/vstudio/vc15_16 [Vollant]
+- Rename contrib/vstudio/vc70_32 to contrib/vstudio/vc7 [Truta]
+- Update README.contrib [Truta]
+- Invert the assignment order of match_head and s->prev[...] in
+  INSERT_STRING [Truta]
+- Compare TOO_FAR with 32767 instead of 32768, to avoid 16-bit warnings
+  [Truta]
+- Compare function pointers with 0, not with NULL or Z_NULL [Truta]
+- Fix prototype of syncsearch in inflate.c [Truta]
+- Introduce ASMINF macro to be enabled when using an ASM implementation
+  of inflate_fast [Truta]
+- Change NO_DEFLATE to NO_GZCOMPRESS [Truta]
+- Modify test_gzio in example.c to take a single file name as a
+  parameter [Truta]
+- Exit the example.c program if gzopen fails [Truta]
+- Add type casts around strlen in example.c [Truta]
+- Remove casting to sizeof in minigzip.c; give a proper type
+  to the variable compared with SUFFIX_LEN [Truta]
+- Update definitions of STDC and STDC99 in zconf.h [Truta]
+- Synchronize zconf.h with the new Windows DLL interface [Truta]
+- Use SYS16BIT instead of __32BIT__ to distinguish between
+  16- and 32-bit platforms [Truta]
+- Use far memory allocators in small 16-bit memory models for
+  Turbo C [Truta]
+- Add info about the use of ASMV, ASMINF and ZLIB_WINAPI in
+  zlibCompileFlags [Truta]
+- Cygwin has vsnprintf [Wilson]
+- In Windows16, OS_CODE is 0, as in MSDOS [Truta]
+- In Cygwin, OS_CODE is 3 (Unix), not 11 (Windows32) [Wilson]
+
+Changes in 1.2.0.4 (10 August 2003)
+- Minor FAQ updates
+- Be more strict when checking inflateInit2's windowBits parameter
+- Change NO_GUNZIP compile option to NO_GZIP to cover deflate as well
+- Add gzip wrapper option to deflateInit2 using windowBits
+- Add updated QNX rule in configure and qnx directory [Bonnefoy]
+- Make inflate distance-too-far checks more rigorous
+- Clean up FAR usage in inflate
+- Add casting to sizeof() in gzio.c and minigzip.c
+
+Changes in 1.2.0.3 (19 July 2003)
+- Fix silly error in gzungetc() implementation [Vollant]
+- Update contrib/minizip and contrib/vstudio [Vollant]
+- Fix printf format in example.c
+- Correct cdecl support in zconf.in.h [Anisimkov]
+- Minor FAQ updates
+
+Changes in 1.2.0.2 (13 July 2003)
+- Add ZLIB_VERNUM in zlib.h for numerical preprocessor comparisons
+- Attempt to avoid warnings in crc32.c for pointer-int conversion
+- Add AIX to configure, remove aix directory [Bakker]
+- Add some casts to minigzip.c
+- Improve checking after insecure sprintf() or vsprintf() calls
+- Remove #elif's from crc32.c
+- Change leave label to inf_leave in inflate.c and infback.c to avoid
+  library conflicts
+- Remove inflate gzip decoding by default--only enable gzip decoding by
+  special request for stricter backward compatibility
+- Add zlibCompileFlags() function to return compilation information
+- More typecasting in deflate.c to avoid warnings
+- Remove leading underscore from _Capital #defines [Truta]
+- Fix configure to link shared library when testing
+- Add some Windows CE target adjustments [Mai]
+- Remove #define ZLIB_DLL in zconf.h [Vollant]
+- Add zlib.3 [Rodgers]
+- Update RFC URL in deflate.c and algorithm.txt [Mai]
+- Add zlib_dll_FAQ.txt to contrib [Truta]
+- Add UL to some constants [Truta]
+- Update minizip and vstudio [Vollant]
+- Remove vestigial NEED_DUMMY_RETURN from zconf.in.h
+- Expand use of NO_DUMMY_DECL to avoid all dummy structures
+- Added iostream3 to contrib [Schwardt]
+- Replace rewind() with fseek() for WinCE [Truta]
+- Improve setting of zlib format compression level flags
+    - Report 0 for huffman and rle strategies and for level == 0 or 1
+    - Report 2 only for level == 6
+- Only deal with 64K limit when necessary at compile time [Truta]
+- Allow TOO_FAR check to be turned off at compile time [Truta]
+- Add gzclearerr() function [Souza]
+- Add gzungetc() function
+
+Changes in 1.2.0.1 (17 March 2003)
+- Add Z_RLE strategy for run-length encoding [Truta]
+    - When Z_RLE requested, restrict matches to distance one
+    - Update zlib.h, minigzip.c, gzopen(), gzdopen() for Z_RLE
+- Correct FASTEST compilation to allow level == 0
+- Clean up what gets compiled for FASTEST
+- Incorporate changes to zconf.in.h [Vollant]
+    - Refine detection of Turbo C need for dummy returns
+    - Refine ZLIB_DLL compilation
+    - Include additional header file on VMS for off_t typedef
+- Try to use _vsnprintf where it supplants vsprintf [Vollant]
+- Add some casts in inffast.c
+- Enchance comments in zlib.h on what happens if gzprintf() tries to
+  write more than 4095 bytes before compression
+- Remove unused state from inflateBackEnd()
+- Remove exit(0) from minigzip.c, example.c
+- Get rid of all those darn tabs
+- Add "check" target to Makefile.in that does the same thing as "test"
+- Add "mostlyclean" and "maintainer-clean" targets to Makefile.in
+- Update contrib/inflate86 [Anderson]
+- Update contrib/testzlib, contrib/vstudio, contrib/minizip [Vollant]
+- Add msdos and win32 directories with makefiles [Truta]
+- More additions and improvements to the FAQ
+
+Changes in 1.2.0 (9 March 2003)
+- New and improved inflate code
+    - About 20% faster
+    - Does not allocate 32K window unless and until needed
+    - Automatically detects and decompresses gzip streams
+    - Raw inflate no longer needs an extra dummy byte at end
+    - Added inflateBack functions using a callback interface--even faster
+      than inflate, useful for file utilities (gzip, zip)
+    - Added inflateCopy() function to record state for random access on
+      externally generated deflate streams (e.g. in gzip files)
+    - More readable code (I hope)
+- New and improved crc32()
+    - About 50% faster, thanks to suggestions from Rodney Brown
+- Add deflateBound() and compressBound() functions
+- Fix memory leak in deflateInit2()
+- Permit setting dictionary for raw deflate (for parallel deflate)
+- Fix const declaration for gzwrite()
+- Check for some malloc() failures in gzio.c
+- Fix bug in gzopen() on single-byte file 0x1f
+- Fix bug in gzread() on concatenated file with 0x1f at end of buffer
+  and next buffer doesn't start with 0x8b
+- Fix uncompress() to return Z_DATA_ERROR on truncated input
+- Free memory at end of example.c
+- Remove MAX #define in trees.c (conflicted with some libraries)
+- Fix static const's in deflate.c, gzio.c, and zutil.[ch]
+- Declare malloc() and free() in gzio.c if STDC not defined
+- Use malloc() instead of calloc() in zutil.c if int big enough
+- Define STDC for AIX
+- Add aix/ with approach for compiling shared library on AIX
+- Add HP-UX support for shared libraries in configure
+- Add OpenUNIX support for shared libraries in configure
+- Use $cc instead of gcc to build shared library
+- Make prefix directory if needed when installing
+- Correct Macintosh avoidance of typedef Byte in zconf.h
+- Correct Turbo C memory allocation when under Linux
+- Use libz.a instead of -lz in Makefile (assure use of compiled library)
+- Update configure to check for snprintf or vsnprintf functions and their
+  return value, warn during make if using an insecure function
+- Fix configure problem with compile-time knowledge of HAVE_UNISTD_H that
+  is lost when library is used--resolution is to build new zconf.h
+- Documentation improvements (in zlib.h):
+    - Document raw deflate and inflate
+    - Update RFCs URL
+    - Point out that zlib and gzip formats are different
+    - Note that Z_BUF_ERROR is not fatal
+    - Document string limit for gzprintf() and possible buffer overflow
+    - Note requirement on avail_out when flushing
+    - Note permitted values of flush parameter of inflate()
+- Add some FAQs (and even answers) to the FAQ
+- Add contrib/inflate86/ for x86 faster inflate
+- Add contrib/blast/ for PKWare Data Compression Library decompression
+- Add contrib/puff/ simple inflate for deflate format description
+
+Changes in 1.1.4 (11 March 2002)
+- ZFREE was repeated on same allocation on some error conditions.
+  This creates a security problem described in
+  http://www.zlib.org/advisory-2002-03-11.txt
+- Returned incorrect error (Z_MEM_ERROR) on some invalid data
+- Avoid accesses before window for invalid distances with inflate window
+  less than 32K.
+- force windowBits > 8 to avoid a bug in the encoder for a window size
+  of 256 bytes. (A complete fix will be available in 1.1.5).
+
+Changes in 1.1.3 (9 July 1998)
+- fix "an inflate input buffer bug that shows up on rare but persistent
+  occasions" (Mark)
+- fix gzread and gztell for concatenated .gz files (Didier Le Botlan)
+- fix gzseek(..., SEEK_SET) in write mode
+- fix crc check after a gzeek (Frank Faubert)
+- fix miniunzip when the last entry in a zip file is itself a zip file
+  (J Lillge)
+- add contrib/asm586 and contrib/asm686 (Brian Raiter)
+  See http://www.muppetlabs.com/~breadbox/software/assembly.html
+- add support for Delphi 3 in contrib/delphi (Bob Dellaca)
+- add support for C++Builder 3 and Delphi 3 in contrib/delphi2 (Davide Moretti)
+- do not exit prematurely in untgz if 0 at start of block (Magnus Holmgren)
+- use macro EXTERN instead of extern to support DLL for BeOS (Sander Stoks)
+- added a FAQ file
+
+- Support gzdopen on Mac with Metrowerks (Jason Linhart)
+- Do not redefine Byte on Mac (Brad Pettit & Jason Linhart)
+- define SEEK_END too if SEEK_SET is not defined (Albert Chin-A-Young)
+- avoid some warnings with Borland C (Tom Tanner)
+- fix a problem in contrib/minizip/zip.c for 16-bit MSDOS (Gilles Vollant)
+- emulate utime() for WIN32 in contrib/untgz  (Gilles Vollant)
+- allow several arguments to configure (Tim Mooney, Frodo Looijaard)
+- use libdir and includedir in Makefile.in (Tim Mooney)
+- support shared libraries on OSF1 V4 (Tim Mooney)
+- remove so_locations in "make clean"  (Tim Mooney)
+- fix maketree.c compilation error (Glenn, Mark)
+- Python interface to zlib now in Python 1.5 (Jeremy Hylton)
+- new Makefile.riscos (Rich Walker)
+- initialize static descriptors in trees.c for embedded targets (Nick Smith)
+- use "foo-gz" in example.c for RISCOS and VMS (Nick Smith)
+- add the OS/2 files in Makefile.in too (Andrew Zabolotny)
+- fix fdopen and halloc macros for Microsoft C 6.0 (Tom Lane)
+- fix maketree.c to allow clean compilation of inffixed.h (Mark)
+- fix parameter check in deflateCopy (Gunther Nikl)
+- cleanup trees.c, use compressed_len only in debug mode (Christian Spieler)
+- Many portability patches by Christian Spieler:
+  . zutil.c, zutil.h: added "const" for zmem*
+  . Make_vms.com: fixed some typos
+  . Make_vms.com: msdos/Makefile.*: removed zutil.h from some dependency lists
+  . msdos/Makefile.msc: remove "default rtl link library" info from obj files
+  . msdos/Makefile.*: use model-dependent name for the built zlib library
+  . msdos/Makefile.emx, nt/Makefile.emx, nt/Makefile.gcc:
+     new makefiles, for emx (DOS/OS2), emx&rsxnt and mingw32 (Windows 9x / NT)
+- use define instead of typedef for Bytef also for MSC small/medium (Tom Lane)
+- replace __far with _far for better portability (Christian Spieler, Tom Lane)
+- fix test for errno.h in configure (Tim Newsham)
+
+Changes in 1.1.2 (19 March 98)
+- added contrib/minzip, mini zip and unzip based on zlib (Gilles Vollant)
+  See http://www.winimage.com/zLibDll/unzip.html
+- preinitialize the inflate tables for fixed codes, to make the code
+  completely thread safe (Mark)
+- some simplifications and slight speed-up to the inflate code (Mark)
+- fix gzeof on non-compressed files (Allan Schrum)
+- add -std1 option in configure for OSF1 to fix gzprintf (Martin Mokrejs)
+- use default value of 4K for Z_BUFSIZE for 16-bit MSDOS (Tim Wegner + Glenn)
+- added os2/Makefile.def and os2/zlib.def (Andrew Zabolotny)
+- add shared lib support for UNIX_SV4.2MP (MATSUURA Takanori)
+- do not wrap extern "C" around system includes (Tom Lane)
+- mention zlib binding for TCL in README (Andreas Kupries)
+- added amiga/Makefile.pup for Amiga powerUP SAS/C PPC (Andreas Kleinert)
+- allow "make install prefix=..." even after configure (Glenn Randers-Pehrson)
+- allow "configure --prefix $HOME" (Tim Mooney)
+- remove warnings in example.c and gzio.c (Glenn Randers-Pehrson)
+- move Makefile.sas to amiga/Makefile.sas
+
+Changes in 1.1.1 (27 Feb 98)
+- fix macros _tr_tally_* in deflate.h for debug mode  (Glenn Randers-Pehrson)
+- remove block truncation heuristic which had very marginal effect for zlib
+  (smaller lit_bufsize than in gzip 1.2.4) and degraded a little the
+  compression ratio on some files. This also allows inlining _tr_tally for
+  matches in deflate_slow.
+- added msdos/Makefile.w32 for WIN32 Microsoft Visual C++ (Bob Frazier)
+
+Changes in 1.1.0 (24 Feb 98)
+- do not return STREAM_END prematurely in inflate (John Bowler)
+- revert to the zlib 1.0.8 inflate to avoid the gcc 2.8.0 bug (Jeremy Buhler)
+- compile with -DFASTEST to get compression code optimized for speed only
+- in minigzip, try mmap'ing the input file first (Miguel Albrecht)
+- increase size of I/O buffers in minigzip.c and gzio.c (not a big gain
+  on Sun but significant on HP)
+
+- add a pointer to experimental unzip library in README (Gilles Vollant)
+- initialize variable gcc in configure (Chris Herborth)
+
+Changes in 1.0.9 (17 Feb 1998)
+- added gzputs and gzgets functions
+- do not clear eof flag in gzseek (Mark Diekhans)
+- fix gzseek for files in transparent mode (Mark Diekhans)
+- do not assume that vsprintf returns the number of bytes written (Jens Krinke)
+- replace EXPORT with ZEXPORT to avoid conflict with other programs
+- added compress2 in zconf.h, zlib.def, zlib.dnt
+- new asm code from Gilles Vollant in contrib/asm386
+- simplify the inflate code (Mark):
+ . Replace ZALLOC's in huft_build() with single ZALLOC in inflate_blocks_new()
+ . ZALLOC the length list in inflate_trees_fixed() instead of using stack
+ . ZALLOC the value area for huft_build() instead of using stack
+ . Simplify Z_FINISH check in inflate()
+
+- Avoid gcc 2.8.0 comparison bug a little differently than zlib 1.0.8
+- in inftrees.c, avoid cc -O bug on HP (Farshid Elahi)
+- in zconf.h move the ZLIB_DLL stuff earlier to avoid problems with
+  the declaration of FAR (Gilles VOllant)
+- install libz.so* with mode 755 (executable) instead of 644 (Marc Lehmann)
+- read_buf buf parameter of type Bytef* instead of charf*
+- zmemcpy parameters are of type Bytef*, not charf* (Joseph Strout)
+- do not redeclare unlink in minigzip.c for WIN32 (John Bowler)
+- fix check for presence of directories in "make install" (Ian Willis)
+
+Changes in 1.0.8 (27 Jan 1998)
+- fixed offsets in contrib/asm386/gvmat32.asm (Gilles Vollant)
+- fix gzgetc and gzputc for big endian systems (Markus Oberhumer)
+- added compress2() to allow setting the compression level
+- include sys/types.h to get off_t on some systems (Marc Lehmann & QingLong)
+- use constant arrays for the static trees in trees.c instead of computing
+  them at run time (thanks to Ken Raeburn for this suggestion). To create
+  trees.h, compile with GEN_TREES_H and run "make test".
+- check return code of example in "make test" and display result
+- pass minigzip command line options to file_compress
+- simplifying code of inflateSync to avoid gcc 2.8 bug
+
+- support CC="gcc -Wall" in configure -s (QingLong)
+- avoid a flush caused by ftell in gzopen for write mode (Ken Raeburn)
+- fix test for shared library support to avoid compiler warnings
+- zlib.lib -> zlib.dll in msdos/zlib.rc (Gilles Vollant)
+- check for TARGET_OS_MAC in addition to MACOS (Brad Pettit)
+- do not use fdopen for Metrowerks on Mac (Brad Pettit))
+- add checks for gzputc and gzputc in example.c
+- avoid warnings in gzio.c and deflate.c (Andreas Kleinert)
+- use const for the CRC table (Ken Raeburn)
+- fixed "make uninstall" for shared libraries
+- use Tracev instead of Trace in infblock.c
+- in example.c use correct compressed length for test_sync
+- suppress +vnocompatwarnings in configure for HPUX (not always supported)
+
+Changes in 1.0.7 (20 Jan 1998)
+- fix gzseek which was broken in write mode
+- return error for gzseek to negative absolute position
+- fix configure for Linux (Chun-Chung Chen)
+- increase stack space for MSC (Tim Wegner)
+- get_crc_table and inflateSyncPoint are EXPORTed (Gilles Vollant)
+- define EXPORTVA for gzprintf (Gilles Vollant)
+- added man page zlib.3 (Rick Rodgers)
+- for contrib/untgz, fix makedir() and improve Makefile
+
+- check gzseek in write mode in example.c
+- allocate extra buffer for seeks only if gzseek is actually called
+- avoid signed/unsigned comparisons (Tim Wegner, Gilles Vollant)
+- add inflateSyncPoint in zconf.h
+- fix list of exported functions in nt/zlib.dnt and mdsos/zlib.def
+
+Changes in 1.0.6 (19 Jan 1998)
+- add functions gzprintf, gzputc, gzgetc, gztell, gzeof, gzseek, gzrewind and
+  gzsetparams (thanks to Roland Giersig and Kevin Ruland for some of this code)
+- Fix a deflate bug occurring only with compression level 0 (thanks to
+  Andy Buckler for finding this one).
+- In minigzip, pass transparently also the first byte for .Z files.
+- return Z_BUF_ERROR instead of Z_OK if output buffer full in uncompress()
+- check Z_FINISH in inflate (thanks to Marc Schluper)
+- Implement deflateCopy (thanks to Adam Costello)
+- make static libraries by default in configure, add --shared option.
+- move MSDOS or Windows specific files to directory msdos
+- suppress the notion of partial flush to simplify the interface
+  (but the symbol Z_PARTIAL_FLUSH is kept for compatibility with 1.0.4)
+- suppress history buffer provided by application to simplify the interface
+  (this feature was not implemented anyway in 1.0.4)
+- next_in and avail_in must be initialized before calling inflateInit or
+  inflateInit2
+- add EXPORT in all exported functions (for Windows DLL)
+- added Makefile.nt (thanks to Stephen Williams)
+- added the unsupported "contrib" directory:
+   contrib/asm386/ by Gilles Vollant <info@winimage.com>
+        386 asm code replacing longest_match().
+   contrib/iostream/ by Kevin Ruland <kevin@rodin.wustl.edu>
+        A C++ I/O streams interface to the zlib gz* functions
+   contrib/iostream2/  by Tyge Løvset <Tyge.Lovset@cmr.no>
+        Another C++ I/O streams interface
+   contrib/untgz/  by "Pedro A. Aranda Guti\irrez" <paag@tid.es>
+        A very simple tar.gz file extractor using zlib
+   contrib/visual-basic.txt by Carlos Rios <c_rios@sonda.cl>
+        How to use compress(), uncompress() and the gz* functions from VB.
+- pass params -f (filtered data), -h (huffman only), -1 to -9 (compression
+  level) in minigzip (thanks to Tom Lane)
+
+- use const for rommable constants in deflate
+- added test for gzseek and gztell in example.c
+- add undocumented function inflateSyncPoint() (hack for Paul Mackerras)
+- add undocumented function zError to convert error code to string
+  (for Tim Smithers)
+- Allow compilation of gzio with -DNO_DEFLATE to avoid the compression code.
+- Use default memcpy for Symantec MSDOS compiler.
+- Add EXPORT keyword for check_func (needed for Windows DLL)
+- add current directory to LD_LIBRARY_PATH for "make test"
+- create also a link for libz.so.1
+- added support for FUJITSU UXP/DS (thanks to Toshiaki Nomura)
+- use $(SHAREDLIB) instead of libz.so in Makefile.in (for HPUX)
+- added -soname for Linux in configure (Chun-Chung Chen,
+- assign numbers to the exported functions in zlib.def (for Windows DLL)
+- add advice in zlib.h for best usage of deflateSetDictionary
+- work around compiler bug on Atari (cast Z_NULL in call of s->checkfn)
+- allow compilation with ANSI keywords only enabled for TurboC in large model
+- avoid "versionString"[0] (Borland bug)
+- add NEED_DUMMY_RETURN for Borland
+- use variable z_verbose for tracing in debug mode (L. Peter Deutsch).
+- allow compilation with CC
+- defined STDC for OS/2 (David Charlap)
+- limit external names to 8 chars for MVS (Thomas Lund)
+- in minigzip.c, use static buffers only for 16-bit systems
+- fix suffix check for "minigzip -d foo.gz"
+- do not return an error for the 2nd of two consecutive gzflush() (Felix Lee)
+- use _fdopen instead of fdopen for MSC >= 6.0 (Thomas Fanslau)
+- added makelcc.bat for lcc-win32 (Tom St Denis)
+- in Makefile.dj2, use copy and del instead of install and rm (Frank Donahoe)
+- Avoid expanded $Id$. Use "rcs -kb" or "cvs admin -kb" to avoid Id expansion.
+- check for unistd.h in configure (for off_t)
+- remove useless check parameter in inflate_blocks_free
+- avoid useless assignment of s->check to itself in inflate_blocks_new
+- do not flush twice in gzclose (thanks to Ken Raeburn)
+- rename FOPEN as F_OPEN to avoid clash with /usr/include/sys/file.h
+- use NO_ERRNO_H instead of enumeration of operating systems with errno.h
+- work around buggy fclose on pipes for HP/UX
+- support zlib DLL with BORLAND C++ 5.0 (thanks to Glenn Randers-Pehrson)
+- fix configure if CC is already equal to gcc
+
+Changes in 1.0.5 (3 Jan 98)
+- Fix inflate to terminate gracefully when fed corrupted or invalid data
+- Use const for rommable constants in inflate
+- Eliminate memory leaks on error conditions in inflate
+- Removed some vestigial code in inflate
+- Update web address in README
+
+Changes in 1.0.4 (24 Jul 96)
+- In very rare conditions, deflate(s, Z_FINISH) could fail to produce an EOF
+  bit, so the decompressor could decompress all the correct data but went
+  on to attempt decompressing extra garbage data. This affected minigzip too.
+- zlibVersion and gzerror return const char* (needed for DLL)
+- port to RISCOS (no fdopen, no multiple dots, no unlink, no fileno)
+- use z_error only for DEBUG (avoid problem with DLLs)
+
+Changes in 1.0.3 (2 Jul 96)
+- use z_streamp instead of z_stream *, which is now a far pointer in MSDOS
+  small and medium models; this makes the library incompatible with previous
+  versions for these models. (No effect in large model or on other systems.)
+- return OK instead of BUF_ERROR if previous deflate call returned with
+  avail_out as zero but there is nothing to do
+- added memcmp for non STDC compilers
+- define NO_DUMMY_DECL for more Mac compilers (.h files merged incorrectly)
+- define __32BIT__ if __386__ or i386 is defined (pb. with Watcom and SCO)
+- better check for 16-bit mode MSC (avoids problem with Symantec)
+
+Changes in 1.0.2 (23 May 96)
+- added Windows DLL support
+- added a function zlibVersion (for the DLL support)
+- fixed declarations using Bytef in infutil.c (pb with MSDOS medium model)
+- Bytef is define's instead of typedef'd only for Borland C
+- avoid reading uninitialized memory in example.c
+- mention in README that the zlib format is now RFC1950
+- updated Makefile.dj2
+- added algorithm.doc
+
+Changes in 1.0.1 (20 May 96) [1.0 skipped to avoid confusion]
+- fix array overlay in deflate.c which sometimes caused bad compressed data
+- fix inflate bug with empty stored block
+- fix MSDOS medium model which was broken in 0.99
+- fix deflateParams() which could generated bad compressed data.
+- Bytef is define'd instead of typedef'ed (work around Borland bug)
+- added an INDEX file
+- new makefiles for DJGPP (Makefile.dj2), 32-bit Borland (Makefile.b32),
+  Watcom (Makefile.wat), Amiga SAS/C (Makefile.sas)
+- speed up adler32 for modern machines without auto-increment
+- added -ansi for IRIX in configure
+- static_init_done in trees.c is an int
+- define unlink as delete for VMS
+- fix configure for QNX
+- add configure branch for SCO and HPUX
+- avoid many warnings (unused variables, dead assignments, etc...)
+- no fdopen for BeOS
+- fix the Watcom fix for 32 bit mode (define FAR as empty)
+- removed redefinition of Byte for MKWERKS
+- work around an MWKERKS bug (incorrect merge of all .h files)
+
+Changes in 0.99 (27 Jan 96)
+- allow preset dictionary shared between compressor and decompressor
+- allow compression level 0 (no compression)
+- add deflateParams in zlib.h: allow dynamic change of compression level
+  and compression strategy.
+- test large buffers and deflateParams in example.c
+- add optional "configure" to build zlib as a shared library
+- suppress Makefile.qnx, use configure instead
+- fixed deflate for 64-bit systems (detected on Cray)
+- fixed inflate_blocks for 64-bit systems (detected on Alpha)
+- declare Z_DEFLATED in zlib.h (possible parameter for deflateInit2)
+- always return Z_BUF_ERROR when deflate() has nothing to do
+- deflateInit and inflateInit are now macros to allow version checking
+- prefix all global functions and types with z_ with -DZ_PREFIX
+- make falloc completely reentrant (inftrees.c)
+- fixed very unlikely race condition in ct_static_init
+- free in reverse order of allocation to help memory manager
+- use zlib-1.0/* instead of zlib/* inside the tar.gz
+- make zlib warning-free with "gcc -O3 -Wall -Wwrite-strings -Wpointer-arith
+  -Wconversion -Wstrict-prototypes -Wmissing-prototypes"
+- allow gzread on concatenated .gz files
+- deflateEnd now returns Z_DATA_ERROR if it was premature
+- deflate is finally (?) fully deterministic (no matches beyond end of input)
+- Document Z_SYNC_FLUSH
+- add uninstall in Makefile
+- Check for __cpluplus in zlib.h
+- Better test in ct_align for partial flush
+- avoid harmless warnings for Borland C++
+- initialize hash_head in deflate.c
+- avoid warning on fdopen (gzio.c) for HP cc -Aa
+- include stdlib.h for STDC compilers
+- include errno.h for Cray
+- ignore error if ranlib doesn't exist
+- call ranlib twice for NeXTSTEP
+- use exec_prefix instead of prefix for libz.a
+- renamed ct_* as _tr_* to avoid conflict with applications
+- clear z->msg in inflateInit2 before any error return
+- initialize opaque in example.c, gzio.c, deflate.c and inflate.c
+- fixed typo in zconf.h (_GNUC__ => __GNUC__)
+- check for WIN32 in zconf.h and zutil.c (avoid farmalloc in 32-bit mode)
+- fix typo in Make_vms.com (f$trnlnm -> f$getsyi)
+- in fcalloc, normalize pointer if size > 65520 bytes
+- don't use special fcalloc for 32 bit Borland C++
+- use STDC instead of __GO32__ to avoid redeclaring exit, calloc, etc...
+- use Z_BINARY instead of BINARY
+- document that gzclose after gzdopen will close the file
+- allow "a" as mode in gzopen.
+- fix error checking in gzread
+- allow skipping .gz extra-field on pipes
+- added reference to Perl interface in README
+- put the crc table in FAR data (I dislike more and more the medium model :)
+- added get_crc_table
+- added a dimension to all arrays (Borland C can't count).
+- workaround Borland C bug in declaration of inflate_codes_new & inflate_fast
+- guard against multiple inclusion of *.h (for precompiled header on Mac)
+- Watcom C pretends to be Microsoft C small model even in 32 bit mode.
+- don't use unsized arrays to avoid silly warnings by Visual C++:
+     warning C4746: 'inflate_mask' : unsized array treated as  '__far'
+     (what's wrong with far data in far model?).
+- define enum out of inflate_blocks_state to allow compilation with C++
+
+Changes in 0.95 (16 Aug 95)
+- fix MSDOS small and medium model (now easier to adapt to any compiler)
+- inlined send_bits
+- fix the final (:-) bug for deflate with flush (output was correct but
+  not completely flushed in rare occasions).
+- default window size is same for compression and decompression
+  (it's now sufficient to set MAX_WBITS in zconf.h).
+- voidp -> voidpf and voidnp -> voidp (for consistency with other
+  typedefs and because voidnp was not near in large model).
+
+Changes in 0.94 (13 Aug 95)
+- support MSDOS medium model
+- fix deflate with flush (could sometimes generate bad output)
+- fix deflateReset (zlib header was incorrectly suppressed)
+- added support for VMS
+- allow a compression level in gzopen()
+- gzflush now calls fflush
+- For deflate with flush, flush even if no more input is provided.
+- rename libgz.a as libz.a
+- avoid complex expression in infcodes.c triggering Turbo C bug
+- work around a problem with gcc on Alpha (in INSERT_STRING)
+- don't use inline functions (problem with some gcc versions)
+- allow renaming of Byte, uInt, etc... with #define.
+- avoid warning about (unused) pointer before start of array in deflate.c
+- avoid various warnings in gzio.c, example.c, infblock.c, adler32.c, zutil.c
+- avoid reserved word 'new' in trees.c
+
+Changes in 0.93 (25 June 95)
+- temporarily disable inline functions
+- make deflate deterministic
+- give enough lookahead for PARTIAL_FLUSH
+- Set binary mode for stdin/stdout in minigzip.c for OS/2
+- don't even use signed char in inflate (not portable enough)
+- fix inflate memory leak for segmented architectures
+
+Changes in 0.92 (3 May 95)
+- don't assume that char is signed (problem on SGI)
+- Clear bit buffer when starting a stored block
+- no memcpy on Pyramid
+- suppressed inftest.c
+- optimized fill_window, put longest_match inline for gcc
+- optimized inflate on stored blocks.
+- untabify all sources to simplify patches
+
+Changes in 0.91 (2 May 95)
+- Default MEM_LEVEL is 8 (not 9 for Unix) as documented in zlib.h
+- Document the memory requirements in zconf.h
+- added "make install"
+- fix sync search logic in inflateSync
+- deflate(Z_FULL_FLUSH) now works even if output buffer too short
+- after inflateSync, don't scare people with just "lo world"
+- added support for DJGPP
+
+Changes in 0.9 (1 May 95)
+- don't assume that zalloc clears the allocated memory (the TurboC bug
+  was Mark's bug after all :)
+- let again gzread copy uncompressed data unchanged (was working in 0.71)
+- deflate(Z_FULL_FLUSH), inflateReset and inflateSync are now fully implemented
+- added a test of inflateSync in example.c
+- moved MAX_WBITS to zconf.h because users might want to change that.
+- document explicitly that zalloc(64K) on MSDOS must return a normalized
+  pointer (zero offset)
+- added Makefiles for Microsoft C, Turbo C, Borland C++
+- faster crc32()
+
+Changes in 0.8 (29 April 95)
+- added fast inflate (inffast.c)
+- deflate(Z_FINISH) now returns Z_STREAM_END when done. Warning: this
+  is incompatible with previous versions of zlib which returned Z_OK.
+- work around a TurboC compiler bug (bad code for b << 0, see infutil.h)
+  (actually that was not a compiler bug, see 0.81 above)
+- gzread no longer reads one extra byte in certain cases
+- In gzio destroy(), don't reference a freed structure
+- avoid many warnings for MSDOS
+- avoid the ERROR symbol which is used by MS Windows
+
+Changes in 0.71 (14 April 95)
+- Fixed more MSDOS compilation problems :( There is still a bug with
+  TurboC large model.
+
+Changes in 0.7 (14 April 95)
+- Added full inflate support.
+- Simplified the crc32() interface. The pre- and post-conditioning
+  (one's complement) is now done inside crc32(). WARNING: this is
+  incompatible with previous versions; see zlib.h for the new usage.
+
+Changes in 0.61 (12 April 95)
+- workaround for a bug in TurboC. example and minigzip now work on MSDOS.
+
+Changes in 0.6 (11 April 95)
+- added minigzip.c
+- added gzdopen to reopen a file descriptor as gzFile
+- added transparent reading of non-gziped files in gzread.
+- fixed bug in gzread (don't read crc as data)
+- fixed bug in destroy (gzio.c) (don't return Z_STREAM_END for gzclose).
+- don't allocate big arrays in the stack (for MSDOS)
+- fix some MSDOS compilation problems
+
+Changes in 0.5:
+- do real compression in deflate.c. Z_PARTIAL_FLUSH is supported but
+  not yet Z_FULL_FLUSH.
+- support decompression but only in a single step (forced Z_FINISH)
+- added opaque object for zalloc and zfree.
+- added deflateReset and inflateReset
+- added a variable zlib_version for consistency checking.
+- renamed the 'filter' parameter of deflateInit2 as 'strategy'.
+  Added Z_FILTERED and Z_HUFFMAN_ONLY constants.
+
+Changes in 0.4:
+- avoid "zip" everywhere, use zlib instead of ziplib.
+- suppress Z_BLOCK_FLUSH, interpret Z_PARTIAL_FLUSH as block flush
+  if compression method == 8.
+- added adler32 and crc32
+- renamed deflateOptions as deflateInit2, call one or the other but not both
+- added the method parameter for deflateInit2.
+- added inflateInit2
+- simplied considerably deflateInit and inflateInit by not supporting
+  user-provided history buffer. This is supported only in deflateInit2
+  and inflateInit2.
+
+Changes in 0.3:
+- prefix all macro names with Z_
+- use Z_FINISH instead of deflateEnd to finish compression.
+- added Z_HUFFMAN_ONLY
+- added gzerror()
diff --git a/gs/zlib/FAQ b/gs/zlib/FAQ
new file mode 100644
index 000000000..441d910da
--- /dev/null
+++ b/gs/zlib/FAQ
@@ -0,0 +1,339 @@
+
+                Frequently Asked Questions about zlib
+
+
+If your question is not there, please check the zlib home page
+http://www.zlib.org which may have more recent information.
+The lastest zlib FAQ is at http://www.gzip.org/zlib/zlib_faq.html
+
+
+ 1. Is zlib Y2K-compliant?
+
+    Yes. zlib doesn't handle dates.
+
+ 2. Where can I get a Windows DLL version?
+
+    The zlib sources can be compiled without change to produce a DLL.
+    See the file win32/DLL_FAQ.txt in the zlib distribution.
+    Pointers to the precompiled DLL are found in the zlib web site at
+    http://www.zlib.org.
+
+ 3. Where can I get a Visual Basic interface to zlib?
+
+    See
+        * http://www.dogma.net/markn/articles/zlibtool/zlibtool.htm
+        * contrib/visual-basic.txt in the zlib distribution
+        * win32/DLL_FAQ.txt in the zlib distribution
+
+ 4. compress() returns Z_BUF_ERROR.
+
+    Make sure that before the call of compress, the length of the compressed
+    buffer is equal to the total size of the compressed buffer and not
+    zero. For Visual Basic, check that this parameter is passed by reference
+    ("as any"), not by value ("as long").
+
+ 5. deflate() or inflate() returns Z_BUF_ERROR.
+
+    Before making the call, make sure that avail_in and avail_out are not
+    zero. When setting the parameter flush equal to Z_FINISH, also make sure
+    that avail_out is big enough to allow processing all pending input.
+    Note that a Z_BUF_ERROR is not fatal--another call to deflate() or
+    inflate() can be made with more input or output space. A Z_BUF_ERROR
+    may in fact be unavoidable depending on how the functions are used, since
+    it is not possible to tell whether or not there is more output pending
+    when strm.avail_out returns with zero.
+
+ 6. Where's the zlib documentation (man pages, etc.)?
+
+    It's in zlib.h for the moment, and Francis S. Lin has converted it to a
+    web page zlib.html. Volunteers to transform this to Unix-style man pages,
+    please contact us (zlib@gzip.org). Examples of zlib usage are in the files
+    example.c and minigzip.c.
+
+ 7. Why don't you use GNU autoconf or libtool or ...?
+
+    Because we would like to keep zlib as a very small and simple
+    package. zlib is rather portable and doesn't need much configuration.
+
+ 8. I found a bug in zlib.
+
+    Most of the time, such problems are due to an incorrect usage of
+    zlib. Please try to reproduce the problem with a small program and send
+    the corresponding source to us at zlib@gzip.org . Do not send
+    multi-megabyte data files without prior agreement.
+
+ 9. Why do I get "undefined reference to gzputc"?
+
+    If "make test" produces something like
+
+       example.o(.text+0x154): undefined reference to `gzputc'
+
+    check that you don't have old files libz.* in /usr/lib, /usr/local/lib or
+    /usr/X11R6/lib. Remove any old versions, then do "make install".
+
+10. I need a Delphi interface to zlib.
+
+    See the contrib/delphi directory in the zlib distribution.
+
+11. Can zlib handle .zip archives?
+
+    Not by itself, no.  See the directory contrib/minizip in the zlib
+    distribution.
+
+12. Can zlib handle .Z files?
+
+    No, sorry. You have to spawn an uncompress or gunzip subprocess, or adapt
+    the code of uncompress on your own.
+
+13. How can I make a Unix shared library?
+
+    make clean
+    ./configure -s
+    make
+
+14. How do I install a shared zlib library on Unix?
+
+    After the above, then:
+
+    make install
+
+    However, many flavors of Unix come with a shared zlib already installed.
+    Before going to the trouble of compiling a shared version of zlib and
+    trying to install it, you may want to check if it's already there! If you
+    can #include <zlib.h>, it's there. The -lz option will probably link to it.
+
+15. I have a question about OttoPDF.
+
+    We are not the authors of OttoPDF. The real author is on the OttoPDF web
+    site: Joel Hainley, jhainley@myndkryme.com.
+
+16. Can zlib decode Flate data in an Adobe PDF file?
+
+    Yes. See http://www.fastio.com/ (ClibPDF), or http://www.pdflib.com/ .
+    To modify PDF forms, see http://sourceforge.net/projects/acroformtool/ .
+
+17. Why am I getting this "register_frame_info not found" error on Solaris?
+
+    After installing zlib 1.1.4 on Solaris 2.6, running applications using zlib
+    generates an error such as:
+
+        ld.so.1: rpm: fatal: relocation error: file /usr/local/lib/libz.so:
+        symbol __register_frame_info: referenced symbol not found
+
+    The symbol __register_frame_info is not part of zlib, it is generated by
+    the C compiler (cc or gcc). You must recompile applications using zlib
+    which have this problem. This problem is specific to Solaris. See
+    http://www.sunfreeware.com for Solaris versions of zlib and applications
+    using zlib.
+
+18. Why does gzip give an error on a file I make with compress/deflate?
+
+    The compress and deflate functions produce data in the zlib format, which
+    is different and incompatible with the gzip format. The gz* functions in
+    zlib on the other hand use the gzip format. Both the zlib and gzip
+    formats use the same compressed data format internally, but have different
+    headers and trailers around the compressed data.
+
+19. Ok, so why are there two different formats?
+
+    The gzip format was designed to retain the directory information about
+    a single file, such as the name and last modification date. The zlib
+    format on the other hand was designed for in-memory and communication
+    channel applications, and has a much more compact header and trailer and
+    uses a faster integrity check than gzip.
+
+20. Well that's nice, but how do I make a gzip file in memory?
+
+    You can request that deflate write the gzip format instead of the zlib
+    format using deflateInit2(). You can also request that inflate decode
+    the gzip format using inflateInit2(). Read zlib.h for more details.
+
+21. Is zlib thread-safe?
+
+    Yes. However any library routines that zlib uses and any application-
+    provided memory allocation routines must also be thread-safe. zlib's gz*
+    functions use stdio library routines, and most of zlib's functions use the
+    library memory allocation routines by default. zlib's Init functions allow
+    for the application to provide custom memory allocation routines.
+
+    Of course, you should only operate on any given zlib or gzip stream from a
+    single thread at a time.
+
+22. Can I use zlib in my commercial application?
+
+    Yes. Please read the license in zlib.h.
+
+23. Is zlib under the GNU license?
+
+    No. Please read the license in zlib.h.
+
+24. The license says that altered source versions must be "plainly marked". So
+    what exactly do I need to do to meet that requirement?
+
+    You need to change the ZLIB_VERSION and ZLIB_VERNUM #defines in zlib.h. In
+    particular, the final version number needs to be changed to "f", and an
+    identification string should be appended to ZLIB_VERSION. Version numbers
+    x.x.x.f are reserved for modifications to zlib by others than the zlib
+    maintainers. For example, if the version of the base zlib you are altering
+    is "1.2.3.4", then in zlib.h you should change ZLIB_VERNUM to 0x123f, and
+    ZLIB_VERSION to something like "1.2.3.f-zachary-mods-v3". You can also
+    update the version strings in deflate.c and inftrees.c.
+
+    For altered source distributions, you should also note the origin and
+    nature of the changes in zlib.h, as well as in ChangeLog and README, along
+    with the dates of the alterations. The origin should include at least your
+    name (or your company's name), and an email address to contact for help or
+    issues with the library.
+
+    Note that distributing a compiled zlib library along with zlib.h and
+    zconf.h is also a source distribution, and so you should change
+    ZLIB_VERSION and ZLIB_VERNUM and note the origin and nature of the changes
+    in zlib.h as you would for a full source distribution.
+
+25. Will zlib work on a big-endian or little-endian architecture, and can I
+    exchange compressed data between them?
+
+    Yes and yes.
+
+26. Will zlib work on a 64-bit machine?
+
+    It should. It has been tested on 64-bit machines, and has no dependence
+    on any data types being limited to 32-bits in length. If you have any
+    difficulties, please provide a complete problem report to zlib@gzip.org
+
+27. Will zlib decompress data from the PKWare Data Compression Library?
+
+    No. The PKWare DCL uses a completely different compressed data format
+    than does PKZIP and zlib. However, you can look in zlib's contrib/blast
+    directory for a possible solution to your problem.
+
+28. Can I access data randomly in a compressed stream?
+
+    No, not without some preparation. If when compressing you periodically
+    use Z_FULL_FLUSH, carefully write all the pending data at those points,
+    and keep an index of those locations, then you can start decompression
+    at those points. You have to be careful to not use Z_FULL_FLUSH too
+    often, since it can significantly degrade compression.
+
+29. Does zlib work on MVS, OS/390, CICS, etc.?
+
+    We don't know for sure. We have heard occasional reports of success on
+    these systems. If you do use it on one of these, please provide us with
+    a report, instructions, and patches that we can reference when we get
+    these questions. Thanks.
+
+30. Is there some simpler, easier to read version of inflate I can look at
+    to understand the deflate format?
+
+    First off, you should read RFC 1951. Second, yes. Look in zlib's
+    contrib/puff directory.
+
+31. Does zlib infringe on any patents?
+
+    As far as we know, no. In fact, that was originally the whole point behind
+    zlib. Look here for some more information:
+
+    http://www.gzip.org/#faq11
+
+32. Can zlib work with greater than 4 GB of data?
+
+    Yes. inflate() and deflate() will process any amount of data correctly.
+    Each call of inflate() or deflate() is limited to input and output chunks
+    of the maximum value that can be stored in the compiler's "unsigned int"
+    type, but there is no limit to the number of chunks. Note however that the
+    strm.total_in and strm_total_out counters may be limited to 4 GB. These
+    counters are provided as a convenience and are not used internally by
+    inflate() or deflate(). The application can easily set up its own counters
+    updated after each call of inflate() or deflate() to count beyond 4 GB.
+    compress() and uncompress() may be limited to 4 GB, since they operate in a
+    single call. gzseek() and gztell() may be limited to 4 GB depending on how
+    zlib is compiled. See the zlibCompileFlags() function in zlib.h.
+
+    The word "may" appears several times above since there is a 4 GB limit
+    only if the compiler's "long" type is 32 bits. If the compiler's "long"
+    type is 64 bits, then the limit is 16 exabytes.
+
+33. Does zlib have any security vulnerabilities?
+
+    The only one that we are aware of is potentially in gzprintf(). If zlib
+    is compiled to use sprintf() or vsprintf(), then there is no protection
+    against a buffer overflow of a 4K string space, other than the caller of
+    gzprintf() assuring that the output will not exceed 4K. On the other
+    hand, if zlib is compiled to use snprintf() or vsnprintf(), which should
+    normally be the case, then there is no vulnerability. The ./configure
+    script will display warnings if an insecure variation of sprintf() will
+    be used by gzprintf(). Also the zlibCompileFlags() function will return
+    information on what variant of sprintf() is used by gzprintf().
+
+    If you don't have snprintf() or vsnprintf() and would like one, you can
+    find a portable implementation here:
+
+        http://www.ijs.si/software/snprintf/
+
+    Note that you should be using the most recent version of zlib. Versions
+    1.1.3 and before were subject to a double-free vulnerability.
+
+34. Is there a Java version of zlib?
+
+    Probably what you want is to use zlib in Java. zlib is already included
+    as part of the Java SDK in the java.util.zip package. If you really want
+    a version of zlib written in the Java language, look on the zlib home
+    page for links: http://www.zlib.org/
+
+35. I get this or that compiler or source-code scanner warning when I crank it
+    up to maximally-pedantic. Can't you guys write proper code?
+
+    Many years ago, we gave up attempting to avoid warnings on every compiler
+    in the universe. It just got to be a waste of time, and some compilers
+    were downright silly. So now, we simply make sure that the code always
+    works.
+
+36. Valgrind (or some similar memory access checker) says that deflate is
+    performing a conditional jump that depends on an uninitialized value.
+    Isn't that a bug?
+
+    No.  That is intentional for performance reasons, and the output of
+    deflate is not affected.  This only started showing up recently since
+    zlib 1.2.x uses malloc() by default for allocations, whereas earlier
+    versions used calloc(), which zeros out the allocated memory.
+
+37. Will zlib read the (insert any ancient or arcane format here) compressed
+    data format?
+
+    Probably not. Look in the comp.compression FAQ for pointers to various
+    formats and associated software.
+
+38. How can I encrypt/decrypt zip files with zlib?
+
+    zlib doesn't support encryption. The original PKZIP encryption is very weak
+    and can be broken with freely available programs. To get strong encryption,
+    use GnuPG, http://www.gnupg.org/ , which already includes zlib compression.
+    For PKZIP compatible "encryption", look at http://www.info-zip.org/
+
+39. What's the difference between the "gzip" and "deflate" HTTP 1.1 encodings?
+
+    "gzip" is the gzip format, and "deflate" is the zlib format. They should
+    probably have called the second one "zlib" instead to avoid confusion
+    with the raw deflate compressed data format. While the HTTP 1.1 RFC 2616
+    correctly points to the zlib specification in RFC 1950 for the "deflate"
+    transfer encoding, there have been reports of servers and browsers that
+    incorrectly produce or expect raw deflate data per the deflate
+    specficiation in RFC 1951, most notably Microsoft. So even though the
+    "deflate" transfer encoding using the zlib format would be the more
+    efficient approach (and in fact exactly what the zlib format was designed
+    for), using the "gzip" transfer encoding is probably more reliable due to
+    an unfortunate choice of name on the part of the HTTP 1.1 authors.
+
+    Bottom line: use the gzip format for HTTP 1.1 encoding.
+
+40. Does zlib support the new "Deflate64" format introduced by PKWare?
+
+    No. PKWare has apparently decided to keep that format proprietary, since
+    they have not documented it as they have previous compression formats.
+    In any case, the compression improvements are so modest compared to other
+    more modern approaches, that it's not worth the effort to implement.
+
+41. Can you please sign these lengthy legal documents and fax them back to us
+    so that we can use your software in our product?
+
+    No. Go away. Shoo.
diff --git a/gs/zlib/INDEX b/gs/zlib/INDEX
new file mode 100644
index 000000000..0587e5902
--- /dev/null
+++ b/gs/zlib/INDEX
@@ -0,0 +1,51 @@
+ChangeLog       history of changes
+FAQ             Frequently Asked Questions about zlib
+INDEX           this file
+Makefile        makefile for Unix (generated by configure)
+Makefile.in     makefile for Unix (template for configure)
+README          guess what
+algorithm.txt   description of the (de)compression algorithm
+configure       configure script for Unix
+zconf.in.h      template for zconf.h (used by configure)
+
+amiga/          makefiles for Amiga SAS C
+as400/          makefiles for IBM AS/400
+msdos/          makefiles for MSDOS
+old/            makefiles for various architectures and zlib documentation
+                files that have not yet been updated for zlib 1.2.x
+projects/       projects for various Integrated Development Environments
+qnx/            makefiles for QNX
+win32/          makefiles for Windows
+
+                zlib public header files (must be kept):
+zconf.h
+zlib.h
+
+                private source files used to build the zlib library:
+adler32.c
+compress.c
+crc32.c
+crc32.h
+deflate.c
+deflate.h
+gzio.c
+infback.c
+inffast.c
+inffast.h
+inffixed.h
+inflate.c
+inflate.h
+inftrees.c
+inftrees.h
+trees.c
+trees.h
+uncompr.c
+zutil.c
+zutil.h
+
+                source files for sample programs:
+example.c
+minigzip.c
+
+                unsupported contribution by third parties
+See contrib/README.contrib
diff --git a/gs/zlib/Makefile b/gs/zlib/Makefile
new file mode 100644
index 000000000..2fd6e45c4
--- /dev/null
+++ b/gs/zlib/Makefile
@@ -0,0 +1,154 @@
+# Makefile for zlib
+# Copyright (C) 1995-2005 Jean-loup Gailly.
+# For conditions of distribution and use, see copyright notice in zlib.h
+
+# To compile and test, type:
+#    ./configure; make test
+# The call of configure is optional if you don't have special requirements
+# If you wish to build zlib as a shared library, use: ./configure -s
+
+# To use the asm code, type:
+#    cp contrib/asm?86/match.S ./match.S
+#    make LOC=-DASMV OBJA=match.o
+
+# To install /usr/local/lib/libz.* and /usr/local/include/zlib.h, type:
+#    make install
+# To install in $HOME instead of /usr/local, use:
+#    make install prefix=$HOME
+
+CC=cc
+
+CFLAGS=-O
+#CFLAGS=-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7
+#CFLAGS=-g -DDEBUG
+#CFLAGS=-O3 -Wall -Wwrite-strings -Wpointer-arith -Wconversion \
+#           -Wstrict-prototypes -Wmissing-prototypes
+
+LDFLAGS=libz.a
+LDSHARED=$(CC)
+CPP=$(CC) -E
+
+LIBS=libz.a
+SHAREDLIB=libz.so
+SHAREDLIBV=libz.so.1.2.3
+SHAREDLIBM=libz.so.1
+
+AR=ar rc
+RANLIB=ranlib
+TAR=tar
+SHELL=/bin/sh
+EXE=
+
+prefix = /usr/local
+exec_prefix = ${prefix}
+libdir = ${exec_prefix}/lib
+includedir = ${prefix}/include
+mandir = ${prefix}/share/man
+man3dir = ${mandir}/man3
+
+OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
+       zutil.o inflate.o infback.o inftrees.o inffast.o
+
+OBJA =
+# to use the asm code: make OBJA=match.o
+
+TEST_OBJS = example.o minigzip.o
+
+all: example$(EXE) minigzip$(EXE)
+
+check: test
+test: all
+	@LD_LIBRARY_PATH=.:$(LD_LIBRARY_PATH) ; export LD_LIBRARY_PATH; \
+	echo hello world | ./minigzip | ./minigzip -d || \
+	  echo '		*** minigzip test FAILED ***' ; \
+	if ./example; then \
+	  echo '		*** zlib test OK ***'; \
+	else \
+	  echo '		*** zlib test FAILED ***'; \
+	fi
+
+libz.a: $(OBJS) $(OBJA)
+	$(AR) $@ $(OBJS) $(OBJA)
+	-@ ($(RANLIB) $@ || true) >/dev/null 2>&1
+
+match.o: match.S
+	$(CPP) match.S > _match.s
+	$(CC) -c _match.s
+	mv _match.o match.o
+	rm -f _match.s
+
+$(SHAREDLIBV): $(OBJS)
+	$(LDSHARED) -o $@ $(OBJS)
+	rm -f $(SHAREDLIB) $(SHAREDLIBM)
+	ln -s $@ $(SHAREDLIB)
+	ln -s $@ $(SHAREDLIBM)
+
+example$(EXE): example.o $(LIBS)
+	$(CC) $(CFLAGS) -o $@ example.o $(LDFLAGS)
+
+minigzip$(EXE): minigzip.o $(LIBS)
+	$(CC) $(CFLAGS) -o $@ minigzip.o $(LDFLAGS)
+
+install: $(LIBS)
+	-@if [ ! -d $(exec_prefix) ]; then mkdir -p $(exec_prefix); fi
+	-@if [ ! -d $(includedir)  ]; then mkdir -p $(includedir); fi
+	-@if [ ! -d $(libdir)      ]; then mkdir -p $(libdir); fi
+	-@if [ ! -d $(man3dir)     ]; then mkdir -p $(man3dir); fi
+	cp zlib.h zconf.h $(includedir)
+	chmod 644 $(includedir)/zlib.h $(includedir)/zconf.h
+	cp $(LIBS) $(libdir)
+	cd $(libdir); chmod 755 $(LIBS)
+	-@(cd $(libdir); $(RANLIB) libz.a || true) >/dev/null 2>&1
+	cd $(libdir); if test -f $(SHAREDLIBV); then \
+	  rm -f $(SHAREDLIB) $(SHAREDLIBM); \
+	  ln -s $(SHAREDLIBV) $(SHAREDLIB); \
+	  ln -s $(SHAREDLIBV) $(SHAREDLIBM); \
+	  (ldconfig || true)  >/dev/null 2>&1; \
+	fi
+	cp zlib.3 $(man3dir)
+	chmod 644 $(man3dir)/zlib.3
+# The ranlib in install is needed on NeXTSTEP which checks file times
+# ldconfig is for Linux
+
+uninstall:
+	cd $(includedir); \
+	cd $(libdir); rm -f libz.a; \
+	if test -f $(SHAREDLIBV); then \
+	  rm -f $(SHAREDLIBV) $(SHAREDLIB) $(SHAREDLIBM); \
+	fi
+	cd $(man3dir); rm -f zlib.3
+
+mostlyclean: clean
+clean:
+	rm -f *.o *~ example$(EXE) minigzip$(EXE) \
+	   libz.* foo.gz so_locations \
+	   _match.s maketree contrib/infback9/*.o
+
+maintainer-clean: distclean
+distclean: clean
+	cp -p Makefile.in Makefile
+	cp -p zconf.in.h zconf.h
+	rm -f .DS_Store
+
+tags:
+	etags *.[ch]
+
+depend:
+	makedepend -- $(CFLAGS) -- *.[ch]
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+adler32.o: zlib.h zconf.h
+compress.o: zlib.h zconf.h
+crc32.o: crc32.h zlib.h zconf.h
+deflate.o: deflate.h zutil.h zlib.h zconf.h
+example.o: zlib.h zconf.h
+gzio.o: zutil.h zlib.h zconf.h
+inffast.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+inflate.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+infback.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+inftrees.o: zutil.h zlib.h zconf.h inftrees.h
+minigzip.o: zlib.h zconf.h
+trees.o: deflate.h zutil.h zlib.h zconf.h trees.h
+uncompr.o: zlib.h zconf.h
+zutil.o: zutil.h zlib.h zconf.h
diff --git a/gs/zlib/Makefile.in b/gs/zlib/Makefile.in
new file mode 100644
index 000000000..2fd6e45c4
--- /dev/null
+++ b/gs/zlib/Makefile.in
@@ -0,0 +1,154 @@
+# Makefile for zlib
+# Copyright (C) 1995-2005 Jean-loup Gailly.
+# For conditions of distribution and use, see copyright notice in zlib.h
+
+# To compile and test, type:
+#    ./configure; make test
+# The call of configure is optional if you don't have special requirements
+# If you wish to build zlib as a shared library, use: ./configure -s
+
+# To use the asm code, type:
+#    cp contrib/asm?86/match.S ./match.S
+#    make LOC=-DASMV OBJA=match.o
+
+# To install /usr/local/lib/libz.* and /usr/local/include/zlib.h, type:
+#    make install
+# To install in $HOME instead of /usr/local, use:
+#    make install prefix=$HOME
+
+CC=cc
+
+CFLAGS=-O
+#CFLAGS=-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7
+#CFLAGS=-g -DDEBUG
+#CFLAGS=-O3 -Wall -Wwrite-strings -Wpointer-arith -Wconversion \
+#           -Wstrict-prototypes -Wmissing-prototypes
+
+LDFLAGS=libz.a
+LDSHARED=$(CC)
+CPP=$(CC) -E
+
+LIBS=libz.a
+SHAREDLIB=libz.so
+SHAREDLIBV=libz.so.1.2.3
+SHAREDLIBM=libz.so.1
+
+AR=ar rc
+RANLIB=ranlib
+TAR=tar
+SHELL=/bin/sh
+EXE=
+
+prefix = /usr/local
+exec_prefix = ${prefix}
+libdir = ${exec_prefix}/lib
+includedir = ${prefix}/include
+mandir = ${prefix}/share/man
+man3dir = ${mandir}/man3
+
+OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
+       zutil.o inflate.o infback.o inftrees.o inffast.o
+
+OBJA =
+# to use the asm code: make OBJA=match.o
+
+TEST_OBJS = example.o minigzip.o
+
+all: example$(EXE) minigzip$(EXE)
+
+check: test
+test: all
+	@LD_LIBRARY_PATH=.:$(LD_LIBRARY_PATH) ; export LD_LIBRARY_PATH; \
+	echo hello world | ./minigzip | ./minigzip -d || \
+	  echo '		*** minigzip test FAILED ***' ; \
+	if ./example; then \
+	  echo '		*** zlib test OK ***'; \
+	else \
+	  echo '		*** zlib test FAILED ***'; \
+	fi
+
+libz.a: $(OBJS) $(OBJA)
+	$(AR) $@ $(OBJS) $(OBJA)
+	-@ ($(RANLIB) $@ || true) >/dev/null 2>&1
+
+match.o: match.S
+	$(CPP) match.S > _match.s
+	$(CC) -c _match.s
+	mv _match.o match.o
+	rm -f _match.s
+
+$(SHAREDLIBV): $(OBJS)
+	$(LDSHARED) -o $@ $(OBJS)
+	rm -f $(SHAREDLIB) $(SHAREDLIBM)
+	ln -s $@ $(SHAREDLIB)
+	ln -s $@ $(SHAREDLIBM)
+
+example$(EXE): example.o $(LIBS)
+	$(CC) $(CFLAGS) -o $@ example.o $(LDFLAGS)
+
+minigzip$(EXE): minigzip.o $(LIBS)
+	$(CC) $(CFLAGS) -o $@ minigzip.o $(LDFLAGS)
+
+install: $(LIBS)
+	-@if [ ! -d $(exec_prefix) ]; then mkdir -p $(exec_prefix); fi
+	-@if [ ! -d $(includedir)  ]; then mkdir -p $(includedir); fi
+	-@if [ ! -d $(libdir)      ]; then mkdir -p $(libdir); fi
+	-@if [ ! -d $(man3dir)     ]; then mkdir -p $(man3dir); fi
+	cp zlib.h zconf.h $(includedir)
+	chmod 644 $(includedir)/zlib.h $(includedir)/zconf.h
+	cp $(LIBS) $(libdir)
+	cd $(libdir); chmod 755 $(LIBS)
+	-@(cd $(libdir); $(RANLIB) libz.a || true) >/dev/null 2>&1
+	cd $(libdir); if test -f $(SHAREDLIBV); then \
+	  rm -f $(SHAREDLIB) $(SHAREDLIBM); \
+	  ln -s $(SHAREDLIBV) $(SHAREDLIB); \
+	  ln -s $(SHAREDLIBV) $(SHAREDLIBM); \
+	  (ldconfig || true)  >/dev/null 2>&1; \
+	fi
+	cp zlib.3 $(man3dir)
+	chmod 644 $(man3dir)/zlib.3
+# The ranlib in install is needed on NeXTSTEP which checks file times
+# ldconfig is for Linux
+
+uninstall:
+	cd $(includedir); \
+	cd $(libdir); rm -f libz.a; \
+	if test -f $(SHAREDLIBV); then \
+	  rm -f $(SHAREDLIBV) $(SHAREDLIB) $(SHAREDLIBM); \
+	fi
+	cd $(man3dir); rm -f zlib.3
+
+mostlyclean: clean
+clean:
+	rm -f *.o *~ example$(EXE) minigzip$(EXE) \
+	   libz.* foo.gz so_locations \
+	   _match.s maketree contrib/infback9/*.o
+
+maintainer-clean: distclean
+distclean: clean
+	cp -p Makefile.in Makefile
+	cp -p zconf.in.h zconf.h
+	rm -f .DS_Store
+
+tags:
+	etags *.[ch]
+
+depend:
+	makedepend -- $(CFLAGS) -- *.[ch]
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+adler32.o: zlib.h zconf.h
+compress.o: zlib.h zconf.h
+crc32.o: crc32.h zlib.h zconf.h
+deflate.o: deflate.h zutil.h zlib.h zconf.h
+example.o: zlib.h zconf.h
+gzio.o: zutil.h zlib.h zconf.h
+inffast.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+inflate.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+infback.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+inftrees.o: zutil.h zlib.h zconf.h inftrees.h
+minigzip.o: zlib.h zconf.h
+trees.o: deflate.h zutil.h zlib.h zconf.h trees.h
+uncompr.o: zlib.h zconf.h
+zutil.o: zutil.h zlib.h zconf.h
diff --git a/gs/zlib/README b/gs/zlib/README
new file mode 100644
index 000000000..758cc5002
--- /dev/null
+++ b/gs/zlib/README
@@ -0,0 +1,125 @@
+ZLIB DATA COMPRESSION LIBRARY
+
+zlib 1.2.3 is a general purpose data compression library.  All the code is
+thread safe.  The data format used by the zlib library is described by RFCs
+(Request for Comments) 1950 to 1952 in the files
+http://www.ietf.org/rfc/rfc1950.txt (zlib format), rfc1951.txt (deflate format)
+and rfc1952.txt (gzip format). These documents are also available in other
+formats from ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html
+
+All functions of the compression library are documented in the file zlib.h
+(volunteer to write man pages welcome, contact zlib@gzip.org). A usage example
+of the library is given in the file example.c which also tests that the library
+is working correctly. Another example is given in the file minigzip.c. The
+compression library itself is composed of all source files except example.c and
+minigzip.c.
+
+To compile all files and run the test program, follow the instructions given at
+the top of Makefile. In short "make test; make install" should work for most
+machines. For Unix: "./configure; make test; make install". For MSDOS, use one
+of the special makefiles such as Makefile.msc. For VMS, use make_vms.com.
+
+Questions about zlib should be sent to <zlib@gzip.org>, or to Gilles Vollant
+<info@winimage.com> for the Windows DLL version. The zlib home page is
+http://www.zlib.org or http://www.gzip.org/zlib/ Before reporting a problem,
+please check this site to verify that you have the latest version of zlib;
+otherwise get the latest version and check whether the problem still exists or
+not.
+
+PLEASE read the zlib FAQ http://www.gzip.org/zlib/zlib_faq.html before asking
+for help.
+
+Mark Nelson <markn@ieee.org> wrote an article about zlib for the Jan. 1997
+issue of  Dr. Dobb's Journal; a copy of the article is available in
+http://dogma.net/markn/articles/zlibtool/zlibtool.htm
+
+The changes made in version 1.2.3 are documented in the file ChangeLog.
+
+Unsupported third party contributions are provided in directory "contrib".
+
+A Java implementation of zlib is available in the Java Development Kit
+http://java.sun.com/j2se/1.4.2/docs/api/java/util/zip/package-summary.html
+See the zlib home page http://www.zlib.org for details.
+
+A Perl interface to zlib written by Paul Marquess <pmqs@cpan.org> is in the
+CPAN (Comprehensive Perl Archive Network) sites
+http://www.cpan.org/modules/by-module/Compress/
+
+A Python interface to zlib written by A.M. Kuchling <amk@amk.ca> is
+available in Python 1.5 and later versions, see
+http://www.python.org/doc/lib/module-zlib.html
+
+A zlib binding for TCL written by Andreas Kupries <a.kupries@westend.com> is
+availlable at http://www.oche.de/~akupries/soft/trf/trf_zip.html
+
+An experimental package to read and write files in .zip format, written on top
+of zlib by Gilles Vollant <info@winimage.com>, is available in the
+contrib/minizip directory of zlib.
+
+
+Notes for some targets:
+
+- For Windows DLL versions, please see win32/DLL_FAQ.txt
+
+- For 64-bit Irix, deflate.c must be compiled without any optimization. With
+  -O, one libpng test fails. The test works in 32 bit mode (with the -n32
+  compiler flag). The compiler bug has been reported to SGI.
+
+- zlib doesn't work with gcc 2.6.3 on a DEC 3000/300LX under OSF/1 2.1 it works
+  when compiled with cc.
+
+- On Digital Unix 4.0D (formely OSF/1) on AlphaServer, the cc option -std1 is
+  necessary to get gzprintf working correctly. This is done by configure.
+
+- zlib doesn't work on HP-UX 9.05 with some versions of /bin/cc. It works with
+  other compilers. Use "make test" to check your compiler.
+
+- gzdopen is not supported on RISCOS, BEOS and by some Mac compilers.
+
+- For PalmOs, see http://palmzlib.sourceforge.net/
+
+- When building a shared, i.e. dynamic library on Mac OS X, the library must be
+  installed before testing (do "make install" before "make test"), since the
+  library location is specified in the library.
+
+
+Acknowledgments:
+
+  The deflate format used by zlib was defined by Phil Katz. The deflate
+  and zlib specifications were written by L. Peter Deutsch. Thanks to all the
+  people who reported problems and suggested various improvements in zlib;
+  they are too numerous to cite here.
+
+Copyright notice:
+
+ (C) 1995-2004 Jean-loup Gailly and Mark Adler
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+
+  Jean-loup Gailly        Mark Adler
+  jloup@gzip.org          madler@alumni.caltech.edu
+
+If you use the zlib library in a product, we would appreciate *not*
+receiving lengthy legal documents to sign. The sources are provided
+for free but without warranty of any kind.  The library has been
+entirely written by Jean-loup Gailly and Mark Adler; it does not
+include third-party code.
+
+If you redistribute modified sources, we would appreciate that you include
+in the file ChangeLog history information documenting your changes. Please
+read the FAQ for more information on the distribution of modified source
+versions.
diff --git a/gs/zlib/adler32.c b/gs/zlib/adler32.c
new file mode 100644
index 000000000..007ba2627
--- /dev/null
+++ b/gs/zlib/adler32.c
@@ -0,0 +1,149 @@
+/* adler32.c -- compute the Adler-32 checksum of a data stream
+ * Copyright (C) 1995-2004 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* @(#) $Id$ */
+
+#define ZLIB_INTERNAL
+#include "zlib.h"
+
+#define BASE 65521UL    /* largest prime smaller than 65536 */
+#define NMAX 5552
+/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
+
+#define DO1(buf,i)  {adler += (buf)[i]; sum2 += adler;}
+#define DO2(buf,i)  DO1(buf,i); DO1(buf,i+1);
+#define DO4(buf,i)  DO2(buf,i); DO2(buf,i+2);
+#define DO8(buf,i)  DO4(buf,i); DO4(buf,i+4);
+#define DO16(buf)   DO8(buf,0); DO8(buf,8);
+
+/* use NO_DIVIDE if your processor does not do division in hardware */
+#ifdef NO_DIVIDE
+#  define MOD(a) \
+    do { \
+        if (a >= (BASE << 16)) a -= (BASE << 16); \
+        if (a >= (BASE << 15)) a -= (BASE << 15); \
+        if (a >= (BASE << 14)) a -= (BASE << 14); \
+        if (a >= (BASE << 13)) a -= (BASE << 13); \
+        if (a >= (BASE << 12)) a -= (BASE << 12); \
+        if (a >= (BASE << 11)) a -= (BASE << 11); \
+        if (a >= (BASE << 10)) a -= (BASE << 10); \
+        if (a >= (BASE << 9)) a -= (BASE << 9); \
+        if (a >= (BASE << 8)) a -= (BASE << 8); \
+        if (a >= (BASE << 7)) a -= (BASE << 7); \
+        if (a >= (BASE << 6)) a -= (BASE << 6); \
+        if (a >= (BASE << 5)) a -= (BASE << 5); \
+        if (a >= (BASE << 4)) a -= (BASE << 4); \
+        if (a >= (BASE << 3)) a -= (BASE << 3); \
+        if (a >= (BASE << 2)) a -= (BASE << 2); \
+        if (a >= (BASE << 1)) a -= (BASE << 1); \
+        if (a >= BASE) a -= BASE; \
+    } while (0)
+#  define MOD4(a) \
+    do { \
+        if (a >= (BASE << 4)) a -= (BASE << 4); \
+        if (a >= (BASE << 3)) a -= (BASE << 3); \
+        if (a >= (BASE << 2)) a -= (BASE << 2); \
+        if (a >= (BASE << 1)) a -= (BASE << 1); \
+        if (a >= BASE) a -= BASE; \
+    } while (0)
+#else
+#  define MOD(a) a %= BASE
+#  define MOD4(a) a %= BASE
+#endif
+
+/* ========================================================================= */
+uLong ZEXPORT adler32(adler, buf, len)
+    uLong adler;
+    const Bytef *buf;
+    uInt len;
+{
+    unsigned long sum2;
+    unsigned n;
+
+    /* split Adler-32 into component sums */
+    sum2 = (adler >> 16) & 0xffff;
+    adler &= 0xffff;
+
+    /* in case user likes doing a byte at a time, keep it fast */
+    if (len == 1) {
+        adler += buf[0];
+        if (adler >= BASE)
+            adler -= BASE;
+        sum2 += adler;
+        if (sum2 >= BASE)
+            sum2 -= BASE;
+        return adler | (sum2 << 16);
+    }
+
+    /* initial Adler-32 value (deferred check for len == 1 speed) */
+    if (buf == Z_NULL)
+        return 1L;
+
+    /* in case short lengths are provided, keep it somewhat fast */
+    if (len < 16) {
+        while (len--) {
+            adler += *buf++;
+            sum2 += adler;
+        }
+        if (adler >= BASE)
+            adler -= BASE;
+        MOD4(sum2);             /* only added so many BASE's */
+        return adler | (sum2 << 16);
+    }
+
+    /* do length NMAX blocks -- requires just one modulo operation */
+    while (len >= NMAX) {
+        len -= NMAX;
+        n = NMAX / 16;          /* NMAX is divisible by 16 */
+        do {
+            DO16(buf);          /* 16 sums unrolled */
+            buf += 16;
+        } while (--n);
+        MOD(adler);
+        MOD(sum2);
+    }
+
+    /* do remaining bytes (less than NMAX, still just one modulo) */
+    if (len) {                  /* avoid modulos if none remaining */
+        while (len >= 16) {
+            len -= 16;
+            DO16(buf);
+            buf += 16;
+        }
+        while (len--) {
+            adler += *buf++;
+            sum2 += adler;
+        }
+        MOD(adler);
+        MOD(sum2);
+    }
+
+    /* return recombined sums */
+    return adler | (sum2 << 16);
+}
+
+/* ========================================================================= */
+uLong ZEXPORT adler32_combine(adler1, adler2, len2)
+    uLong adler1;
+    uLong adler2;
+    z_off_t len2;
+{
+    unsigned long sum1;
+    unsigned long sum2;
+    unsigned rem;
+
+    /* the derivation of this formula is left as an exercise for the reader */
+    rem = (unsigned)(len2 % BASE);
+    sum1 = adler1 & 0xffff;
+    sum2 = rem * sum1;
+    MOD(sum2);
+    sum1 += (adler2 & 0xffff) + BASE - 1;
+    sum2 += ((adler1 >> 16) & 0xffff) + ((adler2 >> 16) & 0xffff) + BASE - rem;
+    if (sum1 > BASE) sum1 -= BASE;
+    if (sum1 > BASE) sum1 -= BASE;
+    if (sum2 > (BASE << 1)) sum2 -= (BASE << 1);
+    if (sum2 > BASE) sum2 -= BASE;
+    return sum1 | (sum2 << 16);
+}
diff --git a/gs/zlib/algorithm.txt b/gs/zlib/algorithm.txt
new file mode 100644
index 000000000..b022dde31
--- /dev/null
+++ b/gs/zlib/algorithm.txt
@@ -0,0 +1,209 @@
+1. Compression algorithm (deflate)
+
+The deflation algorithm used by gzip (also zip and zlib) is a variation of
+LZ77 (Lempel-Ziv 1977, see reference below). It finds duplicated strings in
+the input data.  The second occurrence of a string is replaced by a
+pointer to the previous string, in the form of a pair (distance,
+length).  Distances are limited to 32K bytes, and lengths are limited
+to 258 bytes. When a string does not occur anywhere in the previous
+32K bytes, it is emitted as a sequence of literal bytes.  (In this
+description, `string' must be taken as an arbitrary sequence of bytes,
+and is not restricted to printable characters.)
+
+Literals or match lengths are compressed with one Huffman tree, and
+match distances are compressed with another tree. The trees are stored
+in a compact form at the start of each block. The blocks can have any
+size (except that the compressed data for one block must fit in
+available memory). A block is terminated when deflate() determines that
+it would be useful to start another block with fresh trees. (This is
+somewhat similar to the behavior of LZW-based _compress_.)
+
+Duplicated strings are found using a hash table. All input strings of
+length 3 are inserted in the hash table. A hash index is computed for
+the next 3 bytes. If the hash chain for this index is not empty, all
+strings in the chain are compared with the current input string, and
+the longest match is selected.
+
+The hash chains are searched starting with the most recent strings, to
+favor small distances and thus take advantage of the Huffman encoding.
+The hash chains are singly linked. There are no deletions from the
+hash chains, the algorithm simply discards matches that are too old.
+
+To avoid a worst-case situation, very long hash chains are arbitrarily
+truncated at a certain length, determined by a runtime option (level
+parameter of deflateInit). So deflate() does not always find the longest
+possible match but generally finds a match which is long enough.
+
+deflate() also defers the selection of matches with a lazy evaluation
+mechanism. After a match of length N has been found, deflate() searches for
+a longer match at the next input byte. If a longer match is found, the
+previous match is truncated to a length of one (thus producing a single
+literal byte) and the process of lazy evaluation begins again. Otherwise,
+the original match is kept, and the next match search is attempted only N
+steps later.
+
+The lazy match evaluation is also subject to a runtime parameter. If
+the current match is long enough, deflate() reduces the search for a longer
+match, thus speeding up the whole process. If compression ratio is more
+important than speed, deflate() attempts a complete second search even if
+the first match is already long enough.
+
+The lazy match evaluation is not performed for the fastest compression
+modes (level parameter 1 to 3). For these fast modes, new strings
+are inserted in the hash table only when no match was found, or
+when the match is not too long. This degrades the compression ratio
+but saves time since there are both fewer insertions and fewer searches.
+
+
+2. Decompression algorithm (inflate)
+
+2.1 Introduction
+
+The key question is how to represent a Huffman code (or any prefix code) so
+that you can decode fast.  The most important characteristic is that shorter
+codes are much more common than longer codes, so pay attention to decoding the
+short codes fast, and let the long codes take longer to decode.
+
+inflate() sets up a first level table that covers some number of bits of
+input less than the length of longest code.  It gets that many bits from the
+stream, and looks it up in the table.  The table will tell if the next
+code is that many bits or less and how many, and if it is, it will tell
+the value, else it will point to the next level table for which inflate()
+grabs more bits and tries to decode a longer code.
+
+How many bits to make the first lookup is a tradeoff between the time it
+takes to decode and the time it takes to build the table.  If building the
+table took no time (and if you had infinite memory), then there would only
+be a first level table to cover all the way to the longest code.  However,
+building the table ends up taking a lot longer for more bits since short
+codes are replicated many times in such a table.  What inflate() does is
+simply to make the number of bits in the first table a variable, and  then
+to set that variable for the maximum speed.
+
+For inflate, which has 286 possible codes for the literal/length tree, the size
+of the first table is nine bits.  Also the distance trees have 30 possible
+values, and the size of the first table is six bits.  Note that for each of
+those cases, the table ended up one bit longer than the ``average'' code
+length, i.e. the code length of an approximately flat code which would be a
+little more than eight bits for 286 symbols and a little less than five bits
+for 30 symbols.
+
+
+2.2 More details on the inflate table lookup
+
+Ok, you want to know what this cleverly obfuscated inflate tree actually
+looks like.  You are correct that it's not a Huffman tree.  It is simply a
+lookup table for the first, let's say, nine bits of a Huffman symbol.  The
+symbol could be as short as one bit or as long as 15 bits.  If a particular
+symbol is shorter than nine bits, then that symbol's translation is duplicated
+in all those entries that start with that symbol's bits.  For example, if the
+symbol is four bits, then it's duplicated 32 times in a nine-bit table.  If a
+symbol is nine bits long, it appears in the table once.
+
+If the symbol is longer than nine bits, then that entry in the table points
+to another similar table for the remaining bits.  Again, there are duplicated
+entries as needed.  The idea is that most of the time the symbol will be short
+and there will only be one table look up.  (That's whole idea behind data
+compression in the first place.)  For the less frequent long symbols, there
+will be two lookups.  If you had a compression method with really long
+symbols, you could have as many levels of lookups as is efficient.  For
+inflate, two is enough.
+
+So a table entry either points to another table (in which case nine bits in
+the above example are gobbled), or it contains the translation for the symbol
+and the number of bits to gobble.  Then you start again with the next
+ungobbled bit.
+
+You may wonder: why not just have one lookup table for how ever many bits the
+longest symbol is?  The reason is that if you do that, you end up spending
+more time filling in duplicate symbol entries than you do actually decoding.
+At least for deflate's output that generates new trees every several 10's of
+kbytes.  You can imagine that filling in a 2^15 entry table for a 15-bit code
+would take too long if you're only decoding several thousand symbols.  At the
+other extreme, you could make a new table for every bit in the code.  In fact,
+that's essentially a Huffman tree.  But then you spend two much time
+traversing the tree while decoding, even for short symbols.
+
+So the number of bits for the first lookup table is a trade of the time to
+fill out the table vs. the time spent looking at the second level and above of
+the table.
+
+Here is an example, scaled down:
+
+The code being decoded, with 10 symbols, from 1 to 6 bits long:
+
+A: 0
+B: 10
+C: 1100
+D: 11010
+E: 11011
+F: 11100
+G: 11101
+H: 11110
+I: 111110
+J: 111111
+
+Let's make the first table three bits long (eight entries):
+
+000: A,1
+001: A,1
+010: A,1
+011: A,1
+100: B,2
+101: B,2
+110: -> table X (gobble 3 bits)
+111: -> table Y (gobble 3 bits)
+
+Each entry is what the bits decode as and how many bits that is, i.e. how
+many bits to gobble.  Or the entry points to another table, with the number of
+bits to gobble implicit in the size of the table.
+
+Table X is two bits long since the longest code starting with 110 is five bits
+long:
+
+00: C,1
+01: C,1
+10: D,2
+11: E,2
+
+Table Y is three bits long since the longest code starting with 111 is six
+bits long:
+
+000: F,2
+001: F,2
+010: G,2
+011: G,2
+100: H,2
+101: H,2
+110: I,3
+111: J,3
+
+So what we have here are three tables with a total of 20 entries that had to
+be constructed.  That's compared to 64 entries for a single table.  Or
+compared to 16 entries for a Huffman tree (six two entry tables and one four
+entry table).  Assuming that the code ideally represents the probability of
+the symbols, it takes on the average 1.25 lookups per symbol.  That's compared
+to one lookup for the single table, or 1.66 lookups per symbol for the
+Huffman tree.
+
+There, I think that gives you a picture of what's going on.  For inflate, the
+meaning of a particular symbol is often more than just a letter.  It can be a
+byte (a "literal"), or it can be either a length or a distance which
+indicates a base value and a number of bits to fetch after the code that is
+added to the base value.  Or it might be the special end-of-block code.  The
+data structures created in inftrees.c try to encode all that information
+compactly in the tables.
+
+
+Jean-loup Gailly        Mark Adler
+jloup@gzip.org          madler@alumni.caltech.edu
+
+
+References:
+
+[LZ77] Ziv J., Lempel A., ``A Universal Algorithm for Sequential Data
+Compression,'' IEEE Transactions on Information Theory, Vol. 23, No. 3,
+pp. 337-343.
+
+``DEFLATE Compressed Data Format Specification'' available in
+http://www.ietf.org/rfc/rfc1951.txt
diff --git a/gs/zlib/amiga/Makefile.pup b/gs/zlib/amiga/Makefile.pup
new file mode 100644
index 000000000..3f7e15537
--- /dev/null
+++ b/gs/zlib/amiga/Makefile.pup
@@ -0,0 +1,66 @@
+# Amiga powerUP (TM) Makefile
+# makefile for libpng and SAS C V6.58/7.00 PPC compiler
+# Copyright (C) 1998 by Andreas R. Kleinert
+
+LIBNAME	= libzip.a
+
+CC	= scppc
+CFLAGS	= NOSTKCHK NOSINT OPTIMIZE OPTGO OPTPEEP OPTINLOCAL OPTINL \
+	  OPTLOOP OPTRDEP=8 OPTDEP=8 OPTCOMP=8 NOVER
+AR	= ppc-amigaos-ar cr
+RANLIB	= ppc-amigaos-ranlib
+LD	= ppc-amigaos-ld -r
+LDFLAGS	= -o
+LDLIBS	= LIB:scppc.a LIB:end.o
+RM	= delete quiet
+
+OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
+       zutil.o inflate.o infback.o inftrees.o inffast.o
+
+TEST_OBJS = example.o minigzip.o
+
+all: example minigzip
+
+check: test
+test: all
+	example
+	echo hello world | minigzip | minigzip -d
+
+$(LIBNAME): $(OBJS)
+	$(AR) $@ $(OBJS)
+	-$(RANLIB) $@
+
+example: example.o $(LIBNAME)
+	$(LD) $(LDFLAGS) $@ LIB:c_ppc.o $@.o $(LIBNAME) $(LDLIBS)
+
+minigzip: minigzip.o $(LIBNAME)
+	$(LD) $(LDFLAGS) $@ LIB:c_ppc.o $@.o $(LIBNAME) $(LDLIBS)
+
+mostlyclean: clean
+clean:
+	$(RM) *.o example minigzip $(LIBNAME) foo.gz
+
+zip:
+	zip -ul9 zlib README ChangeLog Makefile Make????.??? Makefile.?? \
+	  descrip.mms *.[ch]
+
+tgz:
+	cd ..; tar cfz zlib/zlib.tgz zlib/README zlib/ChangeLog zlib/Makefile \
+	  zlib/Make????.??? zlib/Makefile.?? zlib/descrip.mms zlib/*.[ch]
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+adler32.o: zlib.h zconf.h
+compress.o: zlib.h zconf.h
+crc32.o: crc32.h zlib.h zconf.h
+deflate.o: deflate.h zutil.h zlib.h zconf.h
+example.o: zlib.h zconf.h
+gzio.o: zutil.h zlib.h zconf.h
+inffast.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+inflate.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+infback.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+inftrees.o: zutil.h zlib.h zconf.h inftrees.h
+minigzip.o: zlib.h zconf.h
+trees.o: deflate.h zutil.h zlib.h zconf.h trees.h
+uncompr.o: zlib.h zconf.h
+zutil.o: zutil.h zlib.h zconf.h
diff --git a/gs/zlib/amiga/Makefile.sas b/gs/zlib/amiga/Makefile.sas
new file mode 100644
index 000000000..296ef48a2
--- /dev/null
+++ b/gs/zlib/amiga/Makefile.sas
@@ -0,0 +1,65 @@
+# SMakefile for zlib
+# Modified from the standard UNIX Makefile Copyright Jean-loup Gailly
+# Osma Ahvenlampi <Osma.Ahvenlampi@hut.fi>
+# Amiga, SAS/C 6.56 & Smake
+
+CC=sc
+CFLAGS=OPT
+#CFLAGS=OPT CPU=68030
+#CFLAGS=DEBUG=LINE
+LDFLAGS=LIB z.lib
+
+SCOPTIONS=OPTSCHED OPTINLINE OPTALIAS OPTTIME OPTINLOCAL STRMERGE \
+       NOICONS PARMS=BOTH NOSTACKCHECK UTILLIB NOVERSION ERRORREXX \
+       DEF=POSTINC
+
+OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
+       zutil.o inflate.o infback.o inftrees.o inffast.o
+
+TEST_OBJS = example.o minigzip.o
+
+all: SCOPTIONS example minigzip
+
+check: test
+test: all
+	example
+	echo hello world | minigzip | minigzip -d
+
+install: z.lib
+	copy clone zlib.h zconf.h INCLUDE:
+	copy clone z.lib LIB:
+
+z.lib: $(OBJS)
+	oml z.lib r $(OBJS)
+
+example: example.o z.lib
+	$(CC) $(CFLAGS) LINK TO $@ example.o $(LDFLAGS)
+
+minigzip: minigzip.o z.lib
+	$(CC) $(CFLAGS) LINK TO $@ minigzip.o $(LDFLAGS)
+
+mostlyclean: clean
+clean:
+	-delete force quiet example minigzip *.o z.lib foo.gz *.lnk SCOPTIONS
+
+SCOPTIONS: Makefile.sas
+	copy to $@ <from <
+$(SCOPTIONS)
+<
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+adler32.o: zlib.h zconf.h
+compress.o: zlib.h zconf.h
+crc32.o: crc32.h zlib.h zconf.h
+deflate.o: deflate.h zutil.h zlib.h zconf.h
+example.o: zlib.h zconf.h
+gzio.o: zutil.h zlib.h zconf.h
+inffast.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+inflate.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+infback.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+inftrees.o: zutil.h zlib.h zconf.h inftrees.h
+minigzip.o: zlib.h zconf.h
+trees.o: deflate.h zutil.h zlib.h zconf.h trees.h
+uncompr.o: zlib.h zconf.h
+zutil.o: zutil.h zlib.h zconf.h
diff --git a/gs/zlib/as400/bndsrc b/gs/zlib/as400/bndsrc
new file mode 100644
index 000000000..9cf94bb35
--- /dev/null
+++ b/gs/zlib/as400/bndsrc
@@ -0,0 +1,132 @@
+STRPGMEXP PGMLVL(*CURRENT) SIGNATURE('ZLIB')
+
+/*@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@*/
+/*   Version 1.1.3 entry points.                                    */
+/*@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@*/
+
+/********************************************************************/
+/*   *MODULE      ADLER32      ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("adler32")
+
+/********************************************************************/
+/*   *MODULE      COMPRESS     ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("compress")
+  EXPORT SYMBOL("compress2")
+
+/********************************************************************/
+/*   *MODULE      CRC32        ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("crc32")
+  EXPORT SYMBOL("get_crc_table")
+
+/********************************************************************/
+/*   *MODULE      DEFLATE      ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("deflate")
+  EXPORT SYMBOL("deflateEnd")
+  EXPORT SYMBOL("deflateSetDictionary")
+  EXPORT SYMBOL("deflateCopy")
+  EXPORT SYMBOL("deflateReset")
+  EXPORT SYMBOL("deflateParams")
+  EXPORT SYMBOL("deflatePrime")
+  EXPORT SYMBOL("deflateInit_")
+  EXPORT SYMBOL("deflateInit2_")
+
+/********************************************************************/
+/*   *MODULE      GZIO         ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("gzopen")
+  EXPORT SYMBOL("gzdopen")
+  EXPORT SYMBOL("gzsetparams")
+  EXPORT SYMBOL("gzread")
+  EXPORT SYMBOL("gzwrite")
+  EXPORT SYMBOL("gzprintf")
+  EXPORT SYMBOL("gzputs")
+  EXPORT SYMBOL("gzgets")
+  EXPORT SYMBOL("gzputc")
+  EXPORT SYMBOL("gzgetc")
+  EXPORT SYMBOL("gzflush")
+  EXPORT SYMBOL("gzseek")
+  EXPORT SYMBOL("gzrewind")
+  EXPORT SYMBOL("gztell")
+  EXPORT SYMBOL("gzeof")
+  EXPORT SYMBOL("gzclose")
+  EXPORT SYMBOL("gzerror")
+
+/********************************************************************/
+/*   *MODULE      INFLATE      ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("inflate")
+  EXPORT SYMBOL("inflateEnd")
+  EXPORT SYMBOL("inflateSetDictionary")
+  EXPORT SYMBOL("inflateSync")
+  EXPORT SYMBOL("inflateReset")
+  EXPORT SYMBOL("inflateInit_")
+  EXPORT SYMBOL("inflateInit2_")
+  EXPORT SYMBOL("inflateSyncPoint")
+
+/********************************************************************/
+/*   *MODULE      UNCOMPR      ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("uncompress")
+
+/********************************************************************/
+/*   *MODULE      ZUTIL        ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("zlibVersion")
+  EXPORT SYMBOL("zError")
+
+/*@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@*/
+/*   Version 1.2.1 additional entry points.                         */
+/*@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@*/
+
+/********************************************************************/
+/*   *MODULE      COMPRESS     ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("compressBound")
+
+/********************************************************************/
+/*   *MODULE      DEFLATE      ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("deflateBound")
+
+/********************************************************************/
+/*   *MODULE      GZIO         ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("gzungetc")
+  EXPORT SYMBOL("gzclearerr")
+
+/********************************************************************/
+/*   *MODULE      INFBACK      ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("inflateBack")
+  EXPORT SYMBOL("inflateBackEnd")
+  EXPORT SYMBOL("inflateBackInit_")
+
+/********************************************************************/
+/*   *MODULE      INFLATE      ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("inflateCopy")
+
+/********************************************************************/
+/*   *MODULE      ZUTIL        ZLIB         01/02/01  00:15:09      */
+/********************************************************************/
+
+  EXPORT SYMBOL("zlibCompileFlags")
+
+ENDPGMEXP
diff --git a/gs/zlib/as400/compile.clp b/gs/zlib/as400/compile.clp
new file mode 100644
index 000000000..855495150
--- /dev/null
+++ b/gs/zlib/as400/compile.clp
@@ -0,0 +1,123 @@
+/******************************************************************************/
+/*                                                                            */
+/*  ZLIB                                                                      */
+/*                                                                            */
+/*    Compile sources into modules and link them into a service program.      */
+/*                                                                            */
+/******************************************************************************/
+
+             PGM
+
+/*      Configuration adjustable parameters.                                  */
+
+             DCL        VAR(&SRCLIB) TYPE(*CHAR) LEN(10) +
+                          VALUE('ZLIB')                         /* Source library. */
+             DCL        VAR(&SRCFILE) TYPE(*CHAR) LEN(10) +
+                          VALUE('SOURCES')                      /* Source member file. */
+             DCL        VAR(&CTLFILE) TYPE(*CHAR) LEN(10) +
+                          VALUE('TOOLS')                        /* Control member file. */
+
+             DCL        VAR(&MODLIB) TYPE(*CHAR) LEN(10) +
+                          VALUE('ZLIB')                         /* Module library. */
+
+             DCL        VAR(&SRVLIB) TYPE(*CHAR) LEN(10) +
+                          VALUE('LGPL')                         /* Service program library. */
+
+             DCL        VAR(&CFLAGS) TYPE(*CHAR) +
+                          VALUE('OPTIMIZE(40)')                 /* Compile options. */
+
+
+/*      Working storage.                                                      */
+
+             DCL        VAR(&CMDLEN) TYPE(*DEC) LEN(15 5) VALUE(300)    /* Command length. */
+             DCL        VAR(&CMD) TYPE(*CHAR) LEN(512)
+
+
+/*      Compile sources into modules.                                         */
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/ADLER32)               SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/COMPRESS)              SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/CRC32)                 SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/DEFLATE)               SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/GZIO)                  SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/INFBACK)               SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/INFFAST)               SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/INFLATE)               SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/INFTREES)              SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/TREES)                 SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/UNCOMPR)               SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+             CHGVAR     VAR(&CMD) VALUE('CRTCMOD MODULE(' *TCAT &MODLIB *TCAT  +
+                        '/ZUTIL)                 SRCFILE(' *TCAT               +
+                        &SRCLIB *TCAT '/' *TCAT &SRCFILE *TCAT                 +
+                        ') SYSIFCOPT(*IFSIO)' *BCAT &CFLAGS)
+             CALL       PGM(QCMDEXC) PARM(&CMD &CMDLEN)
+
+
+/*      Link modules into a service program.                                  */
+
+             CRTSRVPGM  SRVPGM(&SRVLIB/ZLIB) +
+                          MODULE(&MODLIB/ADLER32     &MODLIB/COMPRESS    +
+                                 &MODLIB/CRC32       &MODLIB/DEFLATE     +
+                                 &MODLIB/GZIO        &MODLIB/INFBACK     +
+                                 &MODLIB/INFFAST     &MODLIB/INFLATE     +
+                                 &MODLIB/INFTREES    &MODLIB/TREES       +
+                                 &MODLIB/UNCOMPR     &MODLIB/ZUTIL)      +
+                          SRCFILE(&SRCLIB/&CTLFILE) SRCMBR(BNDSRC) +
+                          TEXT('ZLIB 1.2.3') TGTRLS(V4R4M0)
+
+             ENDPGM
diff --git a/gs/zlib/as400/readme.txt b/gs/zlib/as400/readme.txt
new file mode 100644
index 000000000..beae13f56
--- /dev/null
+++ b/gs/zlib/as400/readme.txt
@@ -0,0 +1,111 @@
+        ZLIB version 1.2.3 for AS400 installation instructions
+
+I) From an AS400 *SAVF file:
+
+1)      Unpacking archive to an AS400 save file
+
+On the AS400:
+
+_       Create the ZLIB AS400 library:
+
+        CRTLIB LIB(ZLIB) TYPE(PROD) TEXT('ZLIB compression API library')
+
+_       Create a work save file, for example:
+
+                CRTSAVF FILE(ZLIB/ZLIBSAVF)
+
+On a PC connected to the target AS400:
+
+_       Unpack the save file image to a PC file "ZLIBSAVF"
+_       Upload this file into the save file on the AS400, for example
+                using ftp in BINARY mode.
+
+
+2)      Populating the ZLIB AS400 source library
+
+On the AS400:
+
+_       Extract the saved objects into the ZLIB AS400 library using:
+
+RSTOBJ OBJ(*ALL) SAVLIB(ZLIB) DEV(*SAVF) SAVF(ZLIB/ZLIBSAVF) RSTLIB(ZLIB)
+
+
+3)      Customize installation:
+
+_       Edit CL member ZLIB/TOOLS(COMPILE) and change parameters if needed,
+                according to the comments.
+
+_       Compile this member with:
+
+        CRTCLPGM PGM(ZLIB/COMPILE) SRCFILE(ZLIB/TOOLS) SRCMBR(COMPILE)
+
+
+4)      Compile and generate the service program:
+
+_       This can now be done by executing:
+
+        CALL PGM(ZLIB/COMPILE)
+
+
+
+II) From the original source distribution:
+
+1)      On the AS400, create the source library:
+
+        CRTLIB LIB(ZLIB) TYPE(PROD) TEXT('ZLIB compression API library')
+
+2)      Create the source files:
+
+        CRTSRCPF FILE(ZLIB/SOURCES) RCDLEN(112) TEXT('ZLIB library modules')
+        CRTSRCPF FILE(ZLIB/H)       RCDLEN(112) TEXT('ZLIB library includes')
+        CRTSRCPF FILE(ZLIB/TOOLS)   RCDLEN(112) TEXT('ZLIB library control utilities')
+
+3)      From the machine hosting the distribution files, upload them (with
+                FTP in text mode, for example) according to the following table:
+
+    Original    AS400   AS400    AS400 AS400
+    file        file    member   type  description
+                SOURCES                Original ZLIB C subprogram sources
+    adler32.c           ADLER32  C     ZLIB - Compute the Adler-32 checksum of a dta strm
+    compress.c          COMPRESS C     ZLIB - Compress a memory buffer
+    crc32.c             CRC32    C     ZLIB - Compute the CRC-32 of a data stream
+    deflate.c           DEFLATE  C     ZLIB - Compress data using the deflation algorithm
+    gzio.c              GZIO     C     ZLIB - IO on .gz files
+    infback.c           INFBACK  C     ZLIB - Inflate using a callback interface
+    inffast.c           INFFAST  C     ZLIB - Fast proc. literals & length/distance pairs
+    inflate.c           INFLATE  C     ZLIB - Interface to inflate modules
+    inftrees.c          INFTREES C     ZLIB - Generate Huffman trees for efficient decode
+    trees.c             TREES    C     ZLIB - Output deflated data using Huffman coding
+    uncompr.c           UNCOMPR  C     ZLIB - Decompress a memory buffer
+    zutil.c             ZUTIL    C     ZLIB - Target dependent utility functions
+                H                      Original ZLIB C and ILE/RPG include files
+    crc32.h             CRC32    C     ZLIB - CRC32 tables
+    deflate.h           DEFLATE  C     ZLIB - Internal compression state
+    inffast.h           INFFAST  C     ZLIB - Header to use inffast.c
+    inffixed.h          INFFIXED C     ZLIB - Table for decoding fixed codes
+    inflate.h           INFLATE  C     ZLIB - Internal inflate state definitions
+    inftrees.h          INFTREES C     ZLIB - Header to use inftrees.c
+    trees.h             TREES    C     ZLIB - Created automatically with -DGEN_TREES_H
+    zconf.h             ZCONF    C     ZLIB - Compression library configuration
+    zlib.h              ZLIB     C     ZLIB - Compression library C user interface
+    as400/zlib.inc      ZLIB.INC RPGLE ZLIB - Compression library ILE RPG user interface
+    zutil.h             ZUTIL    C     ZLIB - Internal interface and configuration
+                TOOLS                  Building source software & AS/400 README
+    as400/bndsrc        BNDSRC         Entry point exportation list
+    as400/compile.clp   COMPILE  CLP   Compile sources & generate service program
+    as400/readme.txt    README   TXT   Installation instructions
+
+4)      Continue as in I)3).
+
+
+
+
+Notes:  For AS400 ILE RPG programmers, a /copy member defining the ZLIB
+                API prototypes for ILE RPG can be found in ZLIB/H(ZLIB.INC).
+                Please read comments in this member for more information.
+
+        Remember that most foreign textual data are ASCII coded: this
+                implementation does not handle conversion from/to ASCII, so
+                text data code conversions must be done explicitely.
+
+        Always open zipped files in binary mode.
diff --git a/gs/zlib/as400/zlib.inc b/gs/zlib/as400/zlib.inc
new file mode 100644
index 000000000..7bbfb7e41
--- /dev/null
+++ b/gs/zlib/as400/zlib.inc
@@ -0,0 +1,331 @@
+      *  ZLIB.INC - Interface to the general purpose compression library
+      *
+      *  ILE RPG400 version by Patrick Monnerat, DATASPHERE.
+      *  Version 1.2.3
+      *
+      *
+      *  WARNING:
+      *     Procedures inflateInit(), inflateInit2(), deflateInit(),
+      *         deflateInit2() and inflateBackInit() need to be called with
+      *         two additional arguments:
+      *         the package version string and the stream control structure.
+      *         size. This is needed because RPG lacks some macro feature.
+      *         Call these procedures as:
+      *             inflateInit(...: ZLIB_VERSION: %size(z_stream))
+      *
+      /if not defined(ZLIB_H_)
+      /define ZLIB_H_
+      *
+      **************************************************************************
+      *                               Constants
+      **************************************************************************
+      *
+      *  Versioning information.
+      *
+     D ZLIB_VERSION    C                   '1.2.3'
+     D ZLIB_VERNUM     C                   X'1230'
+      *
+      *  Other equates.
+      *
+     D Z_NO_FLUSH      C                   0
+     D Z_SYNC_FLUSH    C                   2
+     D Z_FULL_FLUSH    C                   3
+     D Z_FINISH        C                   4
+     D Z_BLOCK         C                   5
+      *
+     D Z_OK            C                   0
+     D Z_STREAM_END    C                   1
+     D Z_NEED_DICT     C                   2
+     D Z_ERRNO         C                   -1
+     D Z_STREAM_ERROR  C                   -2
+     D Z_DATA_ERROR    C                   -3
+     D Z_MEM_ERROR     C                   -4
+     D Z_BUF_ERROR     C                   -5
+     DZ_VERSION_ERROR  C                   -6
+      *
+     D Z_NO_COMPRESSION...
+     D                 C                   0
+     D Z_BEST_SPEED    C                   1
+     D Z_BEST_COMPRESSION...
+     D                 C                   9
+     D Z_DEFAULT_COMPRESSION...
+     D                 C                   -1
+      *
+     D Z_FILTERED      C                   1
+     D Z_HUFFMAN_ONLY  C                   2
+     D Z_RLE           C                   3
+     D Z_DEFAULT_STRATEGY...
+     D                 C                   0
+      *
+     D Z_BINARY        C                   0
+     D Z_ASCII         C                   1
+     D Z_UNKNOWN       C                   2
+      *
+     D Z_DEFLATED      C                   8
+      *
+     D Z_NULL          C                   0
+      *
+      **************************************************************************
+      *                                 Types
+      **************************************************************************
+      *
+     D z_streamp       S               *                                        Stream struct ptr
+     D gzFile          S               *                                        File pointer
+     D z_off_t         S             10i 0                                      Stream offsets
+      *
+      **************************************************************************
+      *                               Structures
+      **************************************************************************
+      *
+      *  The GZIP encode/decode stream support structure.
+      *
+     D z_stream        DS                  align based(z_streamp)
+     D  zs_next_in                     *                                        Next input byte
+     D  zs_avail_in                  10U 0                                      Byte cnt at next_in
+     D  zs_total_in                  10U 0                                      Total bytes read
+     D  zs_next_out                    *                                        Output buffer ptr
+     D  zs_avail_out                 10U 0                                      Room left @ next_out
+     D  zs_total_out                 10U 0                                      Total bytes written
+     D  zs_msg                         *                                        Last errmsg or null
+     D  zs_state                       *                                        Internal state
+     D  zs_zalloc                      *   procptr                              Int. state allocator
+     D  zs_free                        *   procptr                              Int. state dealloc.
+     D  zs_opaque                      *                                        Private alloc. data
+     D  zs_data_type                 10i 0                                      ASC/BIN best guess
+     D  zs_adler                     10u 0                                      Uncompr. adler32 val
+     D                               10U 0                                      Reserved
+     D                               10U 0                                      Ptr. alignment
+      *
+      **************************************************************************
+      *                     Utility function prototypes
+      **************************************************************************
+      *
+     D compress        PR            10I 0 extproc('compress')
+     D  dest                      32767    options(*varsize)                    Destination buffer
+     D  destLen                      10U 0                                      Destination length
+     D  source                    32767    const options(*varsize)              Source buffer
+     D  sourceLen                    10u 0 value                                Source length
+      *
+     D compress2       PR            10I 0 extproc('compress2')
+     D  dest                      32767    options(*varsize)                    Destination buffer
+     D  destLen                      10U 0                                      Destination length
+     D  source                    32767    const options(*varsize)              Source buffer
+     D  sourceLen                    10U 0 value                                Source length
+     D  level                        10I 0 value                                Compression level
+      *
+     D compressBound   PR            10U 0 extproc('compressBound')
+     D  sourceLen                    10U 0 value
+      *
+     D uncompress      PR            10I 0 extproc('uncompress')
+     D  dest                      32767    options(*varsize)                    Destination buffer
+     D  destLen                      10U 0                                      Destination length
+     D  source                    32767    const options(*varsize)              Source buffer
+     D  sourceLen                    10U 0 value                                Source length
+      *
+     D gzopen          PR                  extproc('gzopen')
+     D                                     like(gzFile)
+     D  path                           *   value options(*string)               File pathname
+     D  mode                           *   value options(*string)               Open mode
+      *
+     D gzdopen         PR                  extproc('gzdopen')
+     D                                     like(gzFile)
+     D  fd                           10i 0 value                                File descriptor
+     D  mode                           *   value options(*string)               Open mode
+      *
+     D gzsetparams     PR            10I 0 extproc('gzsetparams')
+     D  file                               value like(gzFile)                   File pointer
+     D  level                        10I 0 value
+     D  strategy                     10i 0 value
+      *
+     D gzread          PR            10I 0 extproc('gzread')
+     D  file                               value like(gzFile)                   File pointer
+     D  buf                       32767    options(*varsize)                    Buffer
+     D  len                          10u 0 value                                Buffer length
+      *
+     D gzwrite         PR            10I 0 extproc('gzwrite')
+     D  file                               value like(gzFile)                   File pointer
+     D  buf                       32767    const options(*varsize)              Buffer
+     D  len                          10u 0 value                                Buffer length
+      *
+     D gzputs          PR            10I 0 extproc('gzputs')
+     D  file                               value like(gzFile)                   File pointer
+     D  s                              *   value options(*string)               String to output
+      *
+     D gzgets          PR              *   extproc('gzgets')
+     D  file                               value like(gzFile)                   File pointer
+     D  buf                       32767    options(*varsize)                    Read buffer
+     D  len                          10i 0 value                                Buffer length
+      *
+     D gzflush         PR            10i 0 extproc('gzflush')
+     D  file                               value like(gzFile)                   File pointer
+     D  flush                        10I 0 value                                Type of flush
+      *
+     D gzseek          PR                  extproc('gzseek')
+     D                                     like(z_off_t)
+     D  file                               value like(gzFile)                   File pointer
+     D  offset                             value like(z_off_t)                  Offset
+     D  whence                       10i 0 value                                Origin
+      *
+     D gzrewind        PR            10i 0 extproc('gzrewind')
+     D  file                               value like(gzFile)                   File pointer
+      *
+     D gztell          PR                  extproc('gztell')
+     D                                     like(z_off_t)
+     D  file                               value like(gzFile)                   File pointer
+      *
+     D gzeof           PR            10i 0 extproc('gzeof')
+     D  file                               value like(gzFile)                   File pointer
+      *
+     D gzclose         PR            10i 0 extproc('gzclose')
+     D  file                               value like(gzFile)                   File pointer
+      *
+     D gzerror         PR              *   extproc('gzerror')                   Error string
+     D  file                               value like(gzFile)                   File pointer
+     D  errnum                       10I 0                                      Error code
+      *
+     D gzclearerr      PR                  extproc('gzclearerr')
+     D  file                               value like(gzFile)                   File pointer
+      *
+      **************************************************************************
+      *                        Basic function prototypes
+      **************************************************************************
+      *
+     D zlibVersion     PR              *   extproc('zlibVersion')               Version string
+      *
+     D deflateInit     PR            10I 0 extproc('deflateInit_')              Init. compression
+     D  strm                               like(z_stream)                       Compression stream
+     D  level                        10I 0 value                                Compression level
+     D  version                        *   value options(*string)               Version string
+     D  stream_size                  10i 0 value                                Stream struct. size
+      *
+     D deflate         PR            10I 0 extproc('deflate')                   Compress data
+     D  strm                               like(z_stream)                       Compression stream
+     D  flush                        10I 0 value                                Flush type required
+      *
+     D deflateEnd      PR            10I 0 extproc('deflateEnd')                Termin. compression
+     D  strm                               like(z_stream)                       Compression stream
+      *
+     D inflateInit     PR            10I 0 extproc('inflateInit_')              Init. expansion
+     D  strm                               like(z_stream)                       Expansion stream
+     D  version                        *   value options(*string)               Version string
+     D  stream_size                  10i 0 value                                Stream struct. size
+      *
+     D inflate         PR            10I 0 extproc('inflate')                   Expand data
+     D  strm                               like(z_stream)                       Expansion stream
+     D  flush                        10I 0 value                                Flush type required
+      *
+     D inflateEnd      PR            10I 0 extproc('inflateEnd')                Termin. expansion
+     D  strm                               like(z_stream)                       Expansion stream
+      *
+      **************************************************************************
+      *                        Advanced function prototypes
+      **************************************************************************
+      *
+     D deflateInit2    PR            10I 0 extproc('deflateInit2_')             Init. compression
+     D  strm                               like(z_stream)                       Compression stream
+     D  level                        10I 0 value                                Compression level
+     D  method                       10I 0 value                                Compression method
+     D  windowBits                   10I 0 value                                log2(window size)
+     D  memLevel                     10I 0 value                                Mem/cmpress tradeoff
+     D  strategy                     10I 0 value                                Compression stategy
+     D  version                        *   value options(*string)               Version string
+     D  stream_size                  10i 0 value                                Stream struct. size
+      *
+     D deflateSetDictionary...
+     D                 PR            10I 0 extproc('deflateSetDictionary')      Init. dictionary
+     D  strm                               like(z_stream)                       Compression stream
+     D  dictionary                32767    const options(*varsize)              Dictionary bytes
+     D  dictLength                   10U 0 value                                Dictionary length
+      *
+     D deflateCopy     PR            10I 0 extproc('deflateCopy')               Compress strm 2 strm
+     D  dest                               like(z_stream)                       Destination stream
+     D  source                             like(z_stream)                       Source stream
+      *
+     D deflateReset    PR            10I 0 extproc('deflateReset')              End and init. stream
+     D  strm                               like(z_stream)                       Compression stream
+      *
+     D deflateParams   PR            10I 0 extproc('deflateParams')             Change level & strat
+     D  strm                               like(z_stream)                       Compression stream
+     D  level                        10I 0 value                                Compression level
+     D  strategy                     10I 0 value                                Compression stategy
+      *
+     D deflateBound    PR            10U 0 extproc('deflateBound')              Change level & strat
+     D  strm                               like(z_stream)                       Compression stream
+     D  sourcelen                    10U 0 value                                Compression level
+      *
+     D deflatePrime    PR            10I 0 extproc('deflatePrime')              Change level & strat
+     D  strm                               like(z_stream)                       Compression stream
+     D  bits                         10I 0 value                                Number of bits to insert
+     D  value                        10I 0 value                                Bits to insert
+      *
+     D inflateInit2    PR            10I 0 extproc('inflateInit2_')             Init. expansion
+     D  strm                               like(z_stream)                       Expansion stream
+     D  windowBits                   10I 0 value                                log2(window size)
+     D  version                        *   value options(*string)               Version string
+     D  stream_size                  10i 0 value                                Stream struct. size
+      *
+     D inflateSetDictionary...
+     D                 PR            10I 0 extproc('inflateSetDictionary')      Init. dictionary
+     D  strm                               like(z_stream)                       Expansion stream
+     D  dictionary                32767    const options(*varsize)              Dictionary bytes
+     D  dictLength                   10U 0 value                                Dictionary length
+      *
+     D inflateSync     PR            10I 0 extproc('inflateSync')               Sync. expansion
+     D  strm                               like(z_stream)                       Expansion stream
+      *
+     D inflateCopy     PR            10I 0 extproc('inflateCopy')
+     D  dest                               like(z_stream)                       Destination stream
+     D  source                             like(z_stream)                       Source stream
+      *
+     D inflateReset    PR            10I 0 extproc('inflateReset')              End and init. stream
+     D  strm                               like(z_stream)                       Expansion stream
+      *
+     D inflateBackInit...
+     D                 PR            10I 0 extproc('inflateBackInit_')
+     D  strm                               like(z_stream)                       Expansion stream
+     D  windowBits                   10I 0 value                                Log2(buffer size)
+     D  window                    32767    options(*varsize)                    Buffer
+     D  version                        *   value options(*string)               Version string
+     D  stream_size                  10i 0 value                                Stream struct. size
+      *
+     D inflateBack     PR            10I 0 extproc('inflateBack')
+     D  strm                               like(z_stream)                       Expansion stream
+     D  in                             *   value procptr                        Input function
+     D  in_desc                        *   value                                Input descriptor
+     D  out                            *   value procptr                        Output function
+     D  out_desc                       *   value                                Output descriptor
+      *
+     D inflateBackEnd  PR            10I 0 extproc('inflateBackEnd')
+     D  strm                               like(z_stream)                       Expansion stream
+      *
+     D zlibCompileFlags...
+     D                 PR            10U 0 extproc('zlibCompileFlags')
+      *
+      **************************************************************************
+      *                        Checksum function prototypes
+      **************************************************************************
+      *
+     D adler32         PR            10U 0 extproc('adler32')                   New checksum
+     D  adler                        10U 0 value                                Old checksum
+     D  buf                       32767    const options(*varsize)              Bytes to accumulate
+     D  len                          10U 0 value                                Buffer length
+      *
+     D crc32           PR            10U 0 extproc('crc32')                     New checksum
+     D  crc                          10U 0 value                                Old checksum
+     D  buf                       32767    const options(*varsize)              Bytes to accumulate
+     D  len                          10U 0 value                                Buffer length
+      *
+      **************************************************************************
+      *                     Miscellaneous function prototypes
+      **************************************************************************
+      *
+     D zError          PR              *   extproc('zError')                    Error string
+     D  err                          10I 0 value                                Error code
+      *
+     D inflateSyncPoint...
+     D                 PR            10I 0 extproc('inflateSyncPoint')
+     D  strm                               like(z_stream)                       Expansion stream
+      *
+     D get_crc_table   PR              *   extproc('get_crc_table')             Ptr to ulongs
+      *
+      /endif
diff --git a/gs/zlib/compress.c b/gs/zlib/compress.c
new file mode 100644
index 000000000..df04f0148
--- /dev/null
+++ b/gs/zlib/compress.c
@@ -0,0 +1,79 @@
+/* compress.c -- compress a memory buffer
+ * Copyright (C) 1995-2003 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* @(#) $Id$ */
+
+#define ZLIB_INTERNAL
+#include "zlib.h"
+
+/* ===========================================================================
+     Compresses the source buffer into the destination buffer. The level
+   parameter has the same meaning as in deflateInit.  sourceLen is the byte
+   length of the source buffer. Upon entry, destLen is the total size of the
+   destination buffer, which must be at least 0.1% larger than sourceLen plus
+   12 bytes. Upon exit, destLen is the actual size of the compressed buffer.
+
+     compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
+   memory, Z_BUF_ERROR if there was not enough room in the output buffer,
+   Z_STREAM_ERROR if the level parameter is invalid.
+*/
+int ZEXPORT compress2 (dest, destLen, source, sourceLen, level)
+    Bytef *dest;
+    uLongf *destLen;
+    const Bytef *source;
+    uLong sourceLen;
+    int level;
+{
+    z_stream stream;
+    int err;
+
+    stream.next_in = (Bytef*)source;
+    stream.avail_in = (uInt)sourceLen;
+#ifdef MAXSEG_64K
+    /* Check for source > 64K on 16-bit machine: */
+    if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
+#endif
+    stream.next_out = dest;
+    stream.avail_out = (uInt)*destLen;
+    if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
+
+    stream.zalloc = (alloc_func)0;
+    stream.zfree = (free_func)0;
+    stream.opaque = (voidpf)0;
+
+    err = deflateInit(&stream, level);
+    if (err != Z_OK) return err;
+
+    err = deflate(&stream, Z_FINISH);
+    if (err != Z_STREAM_END) {
+        deflateEnd(&stream);
+        return err == Z_OK ? Z_BUF_ERROR : err;
+    }
+    *destLen = stream.total_out;
+
+    err = deflateEnd(&stream);
+    return err;
+}
+
+/* ===========================================================================
+ */
+int ZEXPORT compress (dest, destLen, source, sourceLen)
+    Bytef *dest;
+    uLongf *destLen;
+    const Bytef *source;
+    uLong sourceLen;
+{
+    return compress2(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION);
+}
+
+/* ===========================================================================
+     If the default memLevel or windowBits for deflateInit() is changed, then
+   this function needs to be updated.
+ */
+uLong ZEXPORT compressBound (sourceLen)
+    uLong sourceLen;
+{
+    return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) + 11;
+}
diff --git a/gs/zlib/configure b/gs/zlib/configure
new file mode 100755
index 000000000..d7ffdc345
--- /dev/null
+++ b/gs/zlib/configure
@@ -0,0 +1,459 @@
+#!/bin/sh
+# configure script for zlib. This script is needed only if
+# you wish to build a shared library and your system supports them,
+# of if you need special compiler, flags or install directory.
+# Otherwise, you can just use directly "make test; make install"
+#
+# To create a shared library, use "configure --shared"; by default a static
+# library is created. If the primitive shared library support provided here
+# does not work, use ftp://prep.ai.mit.edu/pub/gnu/libtool-*.tar.gz
+#
+# To impose specific compiler or flags or install directory, use for example:
+#    prefix=$HOME CC=cc CFLAGS="-O4" ./configure
+# or for csh/tcsh users:
+#    (setenv prefix $HOME; setenv CC cc; setenv CFLAGS "-O4"; ./configure)
+# LDSHARED is the command to be used to create a shared library
+
+# Incorrect settings of CC or CFLAGS may prevent creating a shared library.
+# If you have problems, try without defining CC and CFLAGS before reporting
+# an error.
+
+LIBS=libz.a
+LDFLAGS="-L. ${LIBS}"
+VER=`sed -n -e '/VERSION "/s/.*"\(.*\)".*/\1/p' < zlib.h`
+VER2=`sed -n -e '/VERSION "/s/.*"\([0-9]*\\.[0-9]*\)\\..*/\1/p' < zlib.h`
+VER1=`sed -n -e '/VERSION "/s/.*"\([0-9]*\)\\..*/\1/p' < zlib.h`
+AR=${AR-"ar rc"}
+RANLIB=${RANLIB-"ranlib"}
+prefix=${prefix-/usr/local}
+exec_prefix=${exec_prefix-'${prefix}'}
+libdir=${libdir-'${exec_prefix}/lib'}
+includedir=${includedir-'${prefix}/include'}
+mandir=${mandir-'${prefix}/share/man'}
+shared_ext='.so'
+shared=0
+gcc=0
+old_cc="$CC"
+old_cflags="$CFLAGS"
+
+while test $# -ge 1
+do
+case "$1" in
+    -h* | --h*)
+      echo 'usage:'
+      echo '  configure [--shared] [--prefix=PREFIX]  [--exec_prefix=EXPREFIX]'
+      echo '     [--libdir=LIBDIR] [--includedir=INCLUDEDIR]'
+        exit 0;;
+    -p*=* | --p*=*) prefix=`echo $1 | sed 's/[-a-z_]*=//'`; shift;;
+    -e*=* | --e*=*) exec_prefix=`echo $1 | sed 's/[-a-z_]*=//'`; shift;;
+    -l*=* | --libdir=*) libdir=`echo $1 | sed 's/[-a-z_]*=//'`; shift;;
+    -i*=* | --includedir=*) includedir=`echo $1 | sed 's/[-a-z_]*=//'`;shift;;
+    -p* | --p*) prefix="$2"; shift; shift;;
+    -e* | --e*) exec_prefix="$2"; shift; shift;;
+    -l* | --l*) libdir="$2"; shift; shift;;
+    -i* | --i*) includedir="$2"; shift; shift;;
+    -s* | --s*) shared=1; shift;;
+    *) echo "unknown option: $1"; echo "$0 --help for help"; exit 1;;
+    esac
+done
+
+test=ztest$$
+cat > $test.c <<EOF
+extern int getchar();
+int hello() {return getchar();}
+EOF
+
+test -z "$CC" && echo Checking for gcc...
+cc=${CC-gcc}
+cflags=${CFLAGS-"-O3"}
+# to force the asm version use: CFLAGS="-O3 -DASMV" ./configure
+case "$cc" in
+  *gcc*) gcc=1;;
+esac
+
+if test "$gcc" -eq 1 && ($cc -c $cflags $test.c) 2>/dev/null; then
+  CC="$cc"
+  SFLAGS=${CFLAGS-"-fPIC -O3"}
+  CFLAGS="$cflags"
+  case `(uname -s || echo unknown) 2>/dev/null` in
+  Linux | linux | GNU | GNU/*) LDSHARED=${LDSHARED-"$cc -shared -Wl,-soname,libz.so.1"};;
+  CYGWIN* | Cygwin* | cygwin* | OS/2* )
+             EXE='.exe';;
+  QNX*)  # This is for QNX6. I suppose that the QNX rule below is for QNX2,QNX4
+         # (alain.bonnefoy@icbt.com)
+                 LDSHARED=${LDSHARED-"$cc -shared -Wl,-hlibz.so.1"};;
+  HP-UX*)
+         LDSHARED=${LDSHARED-"$cc -shared $SFLAGS"}
+         case `(uname -m || echo unknown) 2>/dev/null` in
+         ia64)
+                 shared_ext='.so'
+                 SHAREDLIB='libz.so';;
+         *)
+                 shared_ext='.sl'
+                 SHAREDLIB='libz.sl';;
+         esac;;
+  Darwin*)   shared_ext='.dylib'
+             SHAREDLIB=libz$shared_ext
+             SHAREDLIBV=libz.$VER$shared_ext
+             SHAREDLIBM=libz.$VER1$shared_ext
+             LDSHARED=${LDSHARED-"$cc -dynamiclib -install_name $libdir/$SHAREDLIBM -compatibility_version $VER1 -current_version $VER"};;
+  *)             LDSHARED=${LDSHARED-"$cc -shared"};;
+  esac
+else
+  # find system name and corresponding cc options
+  CC=${CC-cc}
+  case `(uname -sr || echo unknown) 2>/dev/null` in
+  HP-UX*)    SFLAGS=${CFLAGS-"-O +z"}
+             CFLAGS=${CFLAGS-"-O"}
+#            LDSHARED=${LDSHARED-"ld -b +vnocompatwarnings"}
+             LDSHARED=${LDSHARED-"ld -b"}
+         case `(uname -m || echo unknown) 2>/dev/null` in
+         ia64)
+             shared_ext='.so'
+             SHAREDLIB='libz.so';;
+         *)
+             shared_ext='.sl'
+             SHAREDLIB='libz.sl';;
+         esac;;
+  IRIX*)     SFLAGS=${CFLAGS-"-ansi -O2 -rpath ."}
+             CFLAGS=${CFLAGS-"-ansi -O2"}
+             LDSHARED=${LDSHARED-"cc -shared"};;
+  OSF1\ V4*) SFLAGS=${CFLAGS-"-O -std1"}
+             CFLAGS=${CFLAGS-"-O -std1"}
+             LDSHARED=${LDSHARED-"cc -shared  -Wl,-soname,libz.so -Wl,-msym -Wl,-rpath,$(libdir) -Wl,-set_version,${VER}:1.0"};;
+  OSF1*)     SFLAGS=${CFLAGS-"-O -std1"}
+             CFLAGS=${CFLAGS-"-O -std1"}
+             LDSHARED=${LDSHARED-"cc -shared"};;
+  QNX*)      SFLAGS=${CFLAGS-"-4 -O"}
+             CFLAGS=${CFLAGS-"-4 -O"}
+             LDSHARED=${LDSHARED-"cc"}
+             RANLIB=${RANLIB-"true"}
+             AR="cc -A";;
+  SCO_SV\ 3.2*) SFLAGS=${CFLAGS-"-O3 -dy -KPIC "}
+             CFLAGS=${CFLAGS-"-O3"}
+             LDSHARED=${LDSHARED-"cc -dy -KPIC -G"};;
+  SunOS\ 5*) SFLAGS=${CFLAGS-"-fast -xcg89 -KPIC -R."}
+             CFLAGS=${CFLAGS-"-fast -xcg89"}
+             LDSHARED=${LDSHARED-"cc -G"};;
+  SunOS\ 4*) SFLAGS=${CFLAGS-"-O2 -PIC"}
+             CFLAGS=${CFLAGS-"-O2"}
+             LDSHARED=${LDSHARED-"ld"};;
+  SunStudio\ 9*) SFLAGS=${CFLAGS-"-DUSE_MMAP -fast -xcode=pic32 -xtarget=ultra3 -xarch=v9b"}
+             CFLAGS=${CFLAGS-"-DUSE_MMAP -fast -xtarget=ultra3 -xarch=v9b"}
+             LDSHARED=${LDSHARED-"cc -xarch=v9b"};;
+  UNIX_System_V\ 4.2.0)
+             SFLAGS=${CFLAGS-"-KPIC -O"}
+             CFLAGS=${CFLAGS-"-O"}
+             LDSHARED=${LDSHARED-"cc -G"};;
+  UNIX_SV\ 4.2MP)
+             SFLAGS=${CFLAGS-"-Kconform_pic -O"}
+             CFLAGS=${CFLAGS-"-O"}
+             LDSHARED=${LDSHARED-"cc -G"};;
+  OpenUNIX\ 5)
+             SFLAGS=${CFLAGS-"-KPIC -O"}
+             CFLAGS=${CFLAGS-"-O"}
+             LDSHARED=${LDSHARED-"cc -G"};;
+  AIX*)  # Courtesy of dbakker@arrayasolutions.com
+             SFLAGS=${CFLAGS-"-O -qmaxmem=8192"}
+             CFLAGS=${CFLAGS-"-O -qmaxmem=8192"}
+             LDSHARED=${LDSHARED-"xlc -G"};;
+  # send working options for other systems to support@gzip.org
+  *)         SFLAGS=${CFLAGS-"-O"}
+             CFLAGS=${CFLAGS-"-O"}
+             LDSHARED=${LDSHARED-"cc -shared"};;
+  esac
+fi
+
+SHAREDLIB=${SHAREDLIB-"libz$shared_ext"}
+SHAREDLIBV=${SHAREDLIBV-"libz$shared_ext.$VER"}
+SHAREDLIBM=${SHAREDLIBM-"libz$shared_ext.$VER1"}
+
+if test $shared -eq 1; then
+  echo Checking for shared library support...
+  # we must test in two steps (cc then ld), required at least on SunOS 4.x
+  if test "`($CC -c $SFLAGS $test.c) 2>&1`" = "" &&
+     test "`($LDSHARED -o $test$shared_ext $test.o) 2>&1`" = ""; then
+    CFLAGS="$SFLAGS"
+    LIBS="$SHAREDLIBV"
+    echo Building shared library $SHAREDLIBV with $CC.
+  elif test -z "$old_cc" -a -z "$old_cflags"; then
+    echo No shared library support.
+    shared=0;
+  else
+    echo 'No shared library support; try without defining CC and CFLAGS'
+    shared=0;
+  fi
+fi
+if test $shared -eq 0; then
+  LDSHARED="$CC"
+  echo Building static library $LIBS version $VER with $CC.
+else
+  LDFLAGS="-L. ${SHAREDLIBV}"
+fi
+
+cat > $test.c <<EOF
+#include <unistd.h>
+int main() { return 0; }
+EOF
+if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
+  sed < zconf.in.h "/HAVE_UNISTD_H/s%0%1%" > zconf.h
+  echo "Checking for unistd.h... Yes."
+else
+  cp -p zconf.in.h zconf.h
+  echo "Checking for unistd.h... No."
+fi
+
+cat > $test.c <<EOF
+#include <stdio.h>
+#include <stdarg.h>
+#include "zconf.h"
+
+int main()
+{
+#ifndef STDC
+  choke me
+#endif
+
+  return 0;
+}
+EOF
+
+if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
+  echo "Checking whether to use vs[n]printf() or s[n]printf()... using vs[n]printf()"
+
+  cat > $test.c <<EOF
+#include <stdio.h>
+#include <stdarg.h>
+
+int mytest(char *fmt, ...)
+{
+  char buf[20];
+  va_list ap;
+
+  va_start(ap, fmt);
+  vsnprintf(buf, sizeof(buf), fmt, ap);
+  va_end(ap);
+  return 0;
+}
+
+int main()
+{
+  return (mytest("Hello%d\n", 1));
+}
+EOF
+
+  if test "`($CC $CFLAGS -o $test $test.c) 2>&1`" = ""; then
+    echo "Checking for vsnprintf() in stdio.h... Yes."
+
+    cat >$test.c <<EOF
+#include <stdio.h>
+#include <stdarg.h>
+
+int mytest(char *fmt, ...)
+{
+  int n;
+  char buf[20];
+  va_list ap;
+
+  va_start(ap, fmt);
+  n = vsnprintf(buf, sizeof(buf), fmt, ap);
+  va_end(ap);
+  return n;
+}
+
+int main()
+{
+  return (mytest("Hello%d\n", 1));
+}
+EOF
+
+    if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
+      echo "Checking for return value of vsnprintf()... Yes."
+    else
+      CFLAGS="$CFLAGS -DHAS_vsnprintf_void"
+      echo "Checking for return value of vsnprintf()... No."
+      echo "  WARNING: apparently vsnprintf() does not return a value. zlib"
+      echo "  can build but will be open to possible string-format security"
+      echo "  vulnerabilities."
+    fi
+  else
+    CFLAGS="$CFLAGS -DNO_vsnprintf"
+    echo "Checking for vsnprintf() in stdio.h... No."
+    echo "  WARNING: vsnprintf() not found, falling back to vsprintf(). zlib"
+    echo "  can build but will be open to possible buffer-overflow security"
+    echo "  vulnerabilities."
+
+    cat >$test.c <<EOF
+#include <stdio.h>
+#include <stdarg.h>
+
+int mytest(char *fmt, ...)
+{
+  int n;
+  char buf[20];
+  va_list ap;
+
+  va_start(ap, fmt);
+  n = vsprintf(buf, fmt, ap);
+  va_end(ap);
+  return n;
+}
+
+int main()
+{
+  return (mytest("Hello%d\n", 1));
+}
+EOF
+
+    if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
+      echo "Checking for return value of vsprintf()... Yes."
+    else
+      CFLAGS="$CFLAGS -DHAS_vsprintf_void"
+      echo "Checking for return value of vsprintf()... No."
+      echo "  WARNING: apparently vsprintf() does not return a value. zlib"
+      echo "  can build but will be open to possible string-format security"
+      echo "  vulnerabilities."
+    fi
+  fi
+else
+  echo "Checking whether to use vs[n]printf() or s[n]printf()... using s[n]printf()"
+
+  cat >$test.c <<EOF
+#include <stdio.h>
+
+int mytest()
+{
+  char buf[20];
+
+  snprintf(buf, sizeof(buf), "%s", "foo");
+  return 0;
+}
+
+int main()
+{
+  return (mytest());
+}
+EOF
+
+  if test "`($CC $CFLAGS -o $test $test.c) 2>&1`" = ""; then
+    echo "Checking for snprintf() in stdio.h... Yes."
+
+    cat >$test.c <<EOF
+#include <stdio.h>
+
+int mytest()
+{
+  char buf[20];
+
+  return snprintf(buf, sizeof(buf), "%s", "foo");
+}
+
+int main()
+{
+  return (mytest());
+}
+EOF
+
+    if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
+      echo "Checking for return value of snprintf()... Yes."
+    else
+      CFLAGS="$CFLAGS -DHAS_snprintf_void"
+      echo "Checking for return value of snprintf()... No."
+      echo "  WARNING: apparently snprintf() does not return a value. zlib"
+      echo "  can build but will be open to possible string-format security"
+      echo "  vulnerabilities."
+    fi
+  else
+    CFLAGS="$CFLAGS -DNO_snprintf"
+    echo "Checking for snprintf() in stdio.h... No."
+    echo "  WARNING: snprintf() not found, falling back to sprintf(). zlib"
+    echo "  can build but will be open to possible buffer-overflow security"
+    echo "  vulnerabilities."
+
+    cat >$test.c <<EOF
+#include <stdio.h>
+
+int mytest()
+{
+  char buf[20];
+
+  return sprintf(buf, "%s", "foo");
+}
+
+int main()
+{
+  return (mytest());
+}
+EOF
+
+    if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
+      echo "Checking for return value of sprintf()... Yes."
+    else
+      CFLAGS="$CFLAGS -DHAS_sprintf_void"
+      echo "Checking for return value of sprintf()... No."
+      echo "  WARNING: apparently sprintf() does not return a value. zlib"
+      echo "  can build but will be open to possible string-format security"
+      echo "  vulnerabilities."
+    fi
+  fi
+fi
+
+cat >$test.c <<EOF
+#include <errno.h>
+int main() { return 0; }
+EOF
+if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
+  echo "Checking for errno.h... Yes."
+else
+  echo "Checking for errno.h... No."
+  CFLAGS="$CFLAGS -DNO_ERRNO_H"
+fi
+
+cat > $test.c <<EOF
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+caddr_t hello() {
+  return mmap((caddr_t)0, (off_t)0, PROT_READ, MAP_SHARED, 0, (off_t)0);
+}
+EOF
+if test "`($CC -c $CFLAGS $test.c) 2>&1`" = ""; then
+  CFLAGS="$CFLAGS -DUSE_MMAP"
+  echo Checking for mmap support... Yes.
+else
+  echo Checking for mmap support... No.
+fi
+
+CPP=${CPP-"$CC -E"}
+case $CFLAGS in
+  *ASMV*)
+    if test "`nm $test.o | grep _hello`" = ""; then
+      CPP="$CPP -DNO_UNDERLINE"
+      echo Checking for underline in external names... No.
+    else
+      echo Checking for underline in external names... Yes.
+    fi;;
+esac
+
+rm -f $test.[co] $test $test$shared_ext
+
+# udpate Makefile
+sed < Makefile.in "
+/^CC *=/s#=.*#=$CC#
+/^CFLAGS *=/s#=.*#=$CFLAGS#
+/^CPP *=/s#=.*#=$CPP#
+/^LDSHARED *=/s#=.*#=$LDSHARED#
+/^LIBS *=/s#=.*#=$LIBS#
+/^SHAREDLIB *=/s#=.*#=$SHAREDLIB#
+/^SHAREDLIBV *=/s#=.*#=$SHAREDLIBV#
+/^SHAREDLIBM *=/s#=.*#=$SHAREDLIBM#
+/^AR *=/s#=.*#=$AR#
+/^RANLIB *=/s#=.*#=$RANLIB#
+/^EXE *=/s#=.*#=$EXE#
+/^prefix *=/s#=.*#=$prefix#
+/^exec_prefix *=/s#=.*#=$exec_prefix#
+/^libdir *=/s#=.*#=$libdir#
+/^includedir *=/s#=.*#=$includedir#
+/^mandir *=/s#=.*#=$mandir#
+/^LDFLAGS *=/s#=.*#=$LDFLAGS#
+" > Makefile
diff --git a/gs/zlib/contrib/README.contrib b/gs/zlib/contrib/README.contrib
new file mode 100644
index 000000000..20afc6215
--- /dev/null
+++ b/gs/zlib/contrib/README.contrib
@@ -0,0 +1,71 @@
+All files under this contrib directory are UNSUPPORTED. There were
+provided by users of zlib and were not tested by the authors of zlib.
+Use at your own risk. Please contact the authors of the contributions
+for help about these, not the zlib authors. Thanks.
+
+
+ada/        by Dmitriy Anisimkov <anisimkov@yahoo.com>
+        Support for Ada
+        See http://zlib-ada.sourceforge.net/
+
+asm586/
+asm686/     by Brian Raiter <breadbox@muppetlabs.com>
+        asm code for Pentium and PPro/PII, using the AT&T (GNU as) syntax
+        See http://www.muppetlabs.com/~breadbox/software/assembly.html
+
+blast/      by Mark Adler <madler@alumni.caltech.edu>
+        Decompressor for output of PKWare Data Compression Library (DCL)
+
+delphi/     by Cosmin Truta <cosmint@cs.ubbcluj.ro>
+        Support for Delphi and C++ Builder
+
+dotzlib/    by Henrik Ravn <henrik@ravn.com>
+        Support for Microsoft .Net and Visual C++ .Net
+
+infback9/   by Mark Adler <madler@alumni.caltech.edu>
+        Unsupported diffs to infback to decode the deflate64 format
+
+inflate86/  by Chris Anderson <christop@charm.net>
+        Tuned x86 gcc asm code to replace inflate_fast()
+
+iostream/   by Kevin Ruland <kevin@rodin.wustl.edu>
+        A C++ I/O streams interface to the zlib gz* functions
+
+iostream2/  by Tyge Løvset <Tyge.Lovset@cmr.no>
+        Another C++ I/O streams interface
+
+iostream3/  by Ludwig Schwardt <schwardt@sun.ac.za>
+            and Kevin Ruland <kevin@rodin.wustl.edu>
+        Yet another C++ I/O streams interface
+
+masm686/    by Dan Higdon <hdan@kinesoft.com>
+            and Chuck Walbourn <chuckw@kinesoft.com>
+        asm code for Pentium Pro/PII, using the MASM syntax
+
+masmx64/    by Gilles Vollant <info@winimage.com>
+	x86 64-bit (AMD64 and Intel EM64t) code for x64 assembler to
+	replace longest_match() and inflate_fast()
+
+masmx86/    by Gilles Vollant <info@winimage.com>
+        x86 asm code to replace longest_match() and inflate_fast(),
+        for Visual C++ and MASM
+
+minizip/    by Gilles Vollant <info@winimage.com>
+        Mini zip and unzip based on zlib
+        See http://www.winimage.com/zLibDll/unzip.html
+
+pascal/     by Bob Dellaca <bobdl@xtra.co.nz> et al.
+        Support for Pascal
+
+puff/       by Mark Adler <madler@alumni.caltech.edu>
+        Small, low memory usage inflate.  Also serves to provide an
+        unambiguous description of the deflate format.
+
+testzlib/   by Gilles Vollant <info@winimage.com>
+        Example of the use of zlib
+
+untgz/      by Pedro A. Aranda Gutierrez <paag@tid.es>
+        A very simple tar.gz file extractor using zlib
+
+vstudio/    by Gilles Vollant <info@winimage.com>
+        Building a minizip-enhanced zlib with Microsoft Visual Studio
diff --git a/gs/zlib/contrib/ada/buffer_demo.adb b/gs/zlib/contrib/ada/buffer_demo.adb
new file mode 100644
index 000000000..46b863810
--- /dev/null
+++ b/gs/zlib/contrib/ada/buffer_demo.adb
@@ -0,0 +1,106 @@
+----------------------------------------------------------------
+--  ZLib for Ada thick binding.                               --
+--                                                            --
+--  Copyright (C) 2002-2004 Dmitriy Anisimkov                 --
+--                                                            --
+--  Open source license information is in the zlib.ads file.  --
+----------------------------------------------------------------
+--
+--  $Id: buffer_demo.adb,v 1.3 2004/09/06 06:55:35 vagul Exp $
+
+--  This demo program provided by Dr Steve Sangwine <sjs@essex.ac.uk>
+--
+--  Demonstration of a problem with Zlib-Ada (already fixed) when a buffer
+--  of exactly the correct size is used for decompressed data, and the last
+--  few bytes passed in to Zlib are checksum bytes.
+
+--  This program compresses a string of text, and then decompresses the
+--  compressed text into a buffer of the same size as the original text.
+
+with Ada.Streams; use Ada.Streams;
+with Ada.Text_IO;
+
+with ZLib; use ZLib;
+
+procedure Buffer_Demo is
+   EOL  : Character renames ASCII.LF;
+   Text : constant String
+     := "Four score and seven years ago our fathers brought forth," & EOL &
+        "upon this continent, a new nation, conceived in liberty," & EOL &
+        "and dedicated to the proposition that `all men are created equal'.";
+
+   Source : Stream_Element_Array (1 .. Text'Length);
+   for Source'Address use Text'Address;
+
+begin
+   Ada.Text_IO.Put (Text);
+   Ada.Text_IO.New_Line;
+   Ada.Text_IO.Put_Line
+     ("Uncompressed size : " & Positive'Image (Text'Length) & " bytes");
+
+   declare
+      Compressed_Data : Stream_Element_Array (1 .. Text'Length);
+      L               : Stream_Element_Offset;
+   begin
+      Compress : declare
+         Compressor : Filter_Type;
+         I : Stream_Element_Offset;
+      begin
+         Deflate_Init (Compressor);
+
+         --  Compress the whole of T at once.
+
+         Translate (Compressor, Source, I, Compressed_Data, L, Finish);
+         pragma Assert (I = Source'Last);
+
+         Close (Compressor);
+
+         Ada.Text_IO.Put_Line
+           ("Compressed size :   "
+            & Stream_Element_Offset'Image (L) & " bytes");
+      end Compress;
+
+      --  Now we decompress the data, passing short blocks of data to Zlib
+      --  (because this demonstrates the problem - the last block passed will
+      --  contain checksum information and there will be no output, only a
+      --  check inside Zlib that the checksum is correct).
+
+      Decompress : declare
+         Decompressor : Filter_Type;
+
+         Uncompressed_Data : Stream_Element_Array (1 .. Text'Length);
+
+         Block_Size : constant := 4;
+         --  This makes sure that the last block contains
+         --  only Adler checksum data.
+
+         P : Stream_Element_Offset := Compressed_Data'First - 1;
+         O : Stream_Element_Offset;
+      begin
+         Inflate_Init (Decompressor);
+
+         loop
+            Translate
+              (Decompressor,
+               Compressed_Data
+                 (P + 1 .. Stream_Element_Offset'Min (P + Block_Size, L)),
+               P,
+               Uncompressed_Data
+                 (Total_Out (Decompressor) + 1 .. Uncompressed_Data'Last),
+               O,
+               No_Flush);
+
+               Ada.Text_IO.Put_Line
+                 ("Total in : " & Count'Image (Total_In (Decompressor)) &
+                  ", out : " & Count'Image (Total_Out (Decompressor)));
+
+               exit when P = L;
+         end loop;
+
+         Ada.Text_IO.New_Line;
+         Ada.Text_IO.Put_Line
+           ("Decompressed text matches original text : "
+             & Boolean'Image (Uncompressed_Data = Source));
+      end Decompress;
+   end;
+end Buffer_Demo;
diff --git a/gs/zlib/contrib/ada/mtest.adb b/gs/zlib/contrib/ada/mtest.adb
new file mode 100644
index 000000000..c4dfd080f
--- /dev/null
+++ b/gs/zlib/contrib/ada/mtest.adb
@@ -0,0 +1,156 @@
+----------------------------------------------------------------
+--  ZLib for Ada thick binding.                               --
+--                                                            --
+--  Copyright (C) 2002-2003 Dmitriy Anisimkov                 --
+--                                                            --
+--  Open source license information is in the zlib.ads file.  --
+----------------------------------------------------------------
+--  Continuous test for ZLib multithreading. If the test would fail
+--  we should provide thread safe allocation routines for the Z_Stream.
+--
+--  $Id: mtest.adb,v 1.4 2004/07/23 07:49:54 vagul Exp $
+
+with ZLib;
+with Ada.Streams;
+with Ada.Numerics.Discrete_Random;
+with Ada.Text_IO;
+with Ada.Exceptions;
+with Ada.Task_Identification;
+
+procedure MTest is
+   use Ada.Streams;
+   use ZLib;
+
+   Stop : Boolean := False;
+
+   pragma Atomic (Stop);
+
+   subtype Visible_Symbols is Stream_Element range 16#20# .. 16#7E#;
+
+   package Random_Elements is
+      new Ada.Numerics.Discrete_Random (Visible_Symbols);
+
+   task type Test_Task;
+
+   task body Test_Task is
+      Buffer : Stream_Element_Array (1 .. 100_000);
+      Gen : Random_Elements.Generator;
+
+      Buffer_First  : Stream_Element_Offset;
+      Compare_First : Stream_Element_Offset;
+
+      Deflate : Filter_Type;
+      Inflate : Filter_Type;
+
+      procedure Further (Item : in Stream_Element_Array);
+
+      procedure Read_Buffer
+        (Item : out Ada.Streams.Stream_Element_Array;
+         Last : out Ada.Streams.Stream_Element_Offset);
+
+      -------------
+      -- Further --
+      -------------
+
+      procedure Further (Item : in Stream_Element_Array) is
+
+         procedure Compare (Item : in Stream_Element_Array);
+
+         -------------
+         -- Compare --
+         -------------
+
+         procedure Compare (Item : in Stream_Element_Array) is
+            Next_First : Stream_Element_Offset := Compare_First + Item'Length;
+         begin
+            if Buffer (Compare_First .. Next_First - 1) /= Item then
+               raise Program_Error;
+            end if;
+
+            Compare_First := Next_First;
+         end Compare;
+
+         procedure Compare_Write is new ZLib.Write (Write => Compare);
+      begin
+         Compare_Write (Inflate, Item, No_Flush);
+      end Further;
+
+      -----------------
+      -- Read_Buffer --
+      -----------------
+
+      procedure Read_Buffer
+        (Item : out Ada.Streams.Stream_Element_Array;
+         Last : out Ada.Streams.Stream_Element_Offset)
+      is
+         Buff_Diff   : Stream_Element_Offset := Buffer'Last - Buffer_First;
+         Next_First : Stream_Element_Offset;
+      begin
+         if Item'Length <= Buff_Diff then
+            Last := Item'Last;
+
+            Next_First := Buffer_First + Item'Length;
+
+            Item := Buffer (Buffer_First .. Next_First - 1);
+
+            Buffer_First := Next_First;
+         else
+            Last := Item'First + Buff_Diff;
+            Item (Item'First .. Last) := Buffer (Buffer_First .. Buffer'Last);
+            Buffer_First := Buffer'Last + 1;
+         end if;
+      end Read_Buffer;
+
+      procedure Translate is new Generic_Translate
+                                   (Data_In  => Read_Buffer,
+                                    Data_Out => Further);
+
+   begin
+      Random_Elements.Reset (Gen);
+
+      Buffer := (others => 20);
+
+      Main : loop
+         for J in Buffer'Range loop
+            Buffer (J) := Random_Elements.Random (Gen);
+
+            Deflate_Init (Deflate);
+            Inflate_Init (Inflate);
+
+            Buffer_First  := Buffer'First;
+            Compare_First := Buffer'First;
+
+            Translate (Deflate);
+
+            if Compare_First /= Buffer'Last + 1 then
+               raise Program_Error;
+            end if;
+
+            Ada.Text_IO.Put_Line
+              (Ada.Task_Identification.Image
+                 (Ada.Task_Identification.Current_Task)
+               & Stream_Element_Offset'Image (J)
+               & ZLib.Count'Image (Total_Out (Deflate)));
+
+            Close (Deflate);
+            Close (Inflate);
+
+            exit Main when Stop;
+         end loop;
+      end loop Main;
+   exception
+      when E : others =>
+         Ada.Text_IO.Put_Line (Ada.Exceptions.Exception_Information (E));
+         Stop := True;
+   end Test_Task;
+
+   Test : array (1 .. 4) of Test_Task;
+
+   pragma Unreferenced (Test);
+
+   Dummy : Character;
+
+begin
+   Ada.Text_IO.Get_Immediate (Dummy);
+   Stop := True;
+end MTest;
diff --git a/gs/zlib/contrib/ada/read.adb b/gs/zlib/contrib/ada/read.adb
new file mode 100644
index 000000000..1f2efbfeb
--- /dev/null
+++ b/gs/zlib/contrib/ada/read.adb
@@ -0,0 +1,156 @@
+----------------------------------------------------------------
+--  ZLib for Ada thick binding.                               --
+--                                                            --
+--  Copyright (C) 2002-2003 Dmitriy Anisimkov                 --
+--                                                            --
+--  Open source license information is in the zlib.ads file.  --
+----------------------------------------------------------------
+
+--  $Id: read.adb,v 1.8 2004/05/31 10:53:40 vagul Exp $
+
+--  Test/demo program for the generic read interface.
+
+with Ada.Numerics.Discrete_Random;
+with Ada.Streams;
+with Ada.Text_IO;
+
+with ZLib;
+
+procedure Read is
+
+   use Ada.Streams;
+
+   ------------------------------------
+   --  Test configuration parameters --
+   ------------------------------------
+
+   File_Size   : Stream_Element_Offset := 100_000;
+
+   Continuous  : constant Boolean          := False;
+   --  If this constant is True, the test would be repeated again and again,
+   --  with increment File_Size for every iteration.
+
+   Header      : constant ZLib.Header_Type := ZLib.Default;
+   --  Do not use Header other than Default in ZLib versions 1.1.4 and older.
+
+   Init_Random : constant := 8;
+   --  We are using the same random sequence, in case of we catch bug,
+   --  so we would be able to reproduce it.
+
+   -- End --
+
+   Pack_Size : Stream_Element_Offset;
+   Offset    : Stream_Element_Offset;
+
+   Filter     : ZLib.Filter_Type;
+
+   subtype Visible_Symbols
+      is Stream_Element range 16#20# .. 16#7E#;
+
+   package Random_Elements is new
+      Ada.Numerics.Discrete_Random (Visible_Symbols);
+
+   Gen : Random_Elements.Generator;
+   Period  : constant Stream_Element_Offset := 200;
+   --  Period constant variable for random generator not to be very random.
+   --  Bigger period, harder random.
+
+   Read_Buffer : Stream_Element_Array (1 .. 2048);
+   Read_First  : Stream_Element_Offset;
+   Read_Last   : Stream_Element_Offset;
+
+   procedure Reset;
+
+   procedure Read
+     (Item : out Stream_Element_Array;
+      Last : out Stream_Element_Offset);
+   --  this procedure is for generic instantiation of
+   --  ZLib.Read
+   --  reading data from the File_In.
+
+   procedure Read is new ZLib.Read
+                           (Read,
+                            Read_Buffer,
+                            Rest_First => Read_First,
+                            Rest_Last  => Read_Last);
+
+   ----------
+   -- Read --
+   ----------
+
+   procedure Read
+     (Item : out Stream_Element_Array;
+      Last : out Stream_Element_Offset) is
+   begin
+      Last := Stream_Element_Offset'Min
+               (Item'Last,
+                Item'First + File_Size - Offset);
+
+      for J in Item'First .. Last loop
+         if J < Item'First + Period then
+            Item (J) := Random_Elements.Random (Gen);
+         else
+            Item (J) := Item (J - Period);
+         end if;
+
+         Offset   := Offset + 1;
+      end loop;
+   end Read;
+
+   -----------
+   -- Reset --
+   -----------
+
+   procedure Reset is
+   begin
+      Random_Elements.Reset (Gen, Init_Random);
+      Pack_Size := 0;
+      Offset := 1;
+      Read_First := Read_Buffer'Last + 1;
+      Read_Last  := Read_Buffer'Last;
+   end Reset;
+
+begin
+   Ada.Text_IO.Put_Line ("ZLib " & ZLib.Version);
+
+   loop
+      for Level in ZLib.Compression_Level'Range loop
+
+         Ada.Text_IO.Put ("Level ="
+            & ZLib.Compression_Level'Image (Level));
+
+         --  Deflate using generic instantiation.
+
+         ZLib.Deflate_Init
+               (Filter,
+                Level,
+                Header => Header);
+
+         Reset;
+
+         Ada.Text_IO.Put
+           (Stream_Element_Offset'Image (File_Size) & " ->");
+
+         loop
+            declare
+               Buffer : Stream_Element_Array (1 .. 1024);
+               Last   : Stream_Element_Offset;
+            begin
+               Read (Filter, Buffer, Last);
+
+               Pack_Size := Pack_Size + Last - Buffer'First + 1;
+
+               exit when Last < Buffer'Last;
+            end;
+         end loop;
+
+         Ada.Text_IO.Put_Line (Stream_Element_Offset'Image (Pack_Size));
+
+         ZLib.Close (Filter);
+      end loop;
+
+      exit when not Continuous;
+
+      File_Size := File_Size + 1;
+   end loop;
+end Read;
diff --git a/gs/zlib/contrib/ada/readme.txt b/gs/zlib/contrib/ada/readme.txt
new file mode 100644
index 000000000..ce4d2cadf
--- /dev/null
+++ b/gs/zlib/contrib/ada/readme.txt
@@ -0,0 +1,65 @@
+                        ZLib for Ada thick binding (ZLib.Ada)
+                        Release 1.3
+
+ZLib.Ada is a thick binding interface to the popular ZLib data
+compression library, available at http://www.gzip.org/zlib/.
+It provides Ada-style access to the ZLib C library.
+
+
+        Here are the main changes since ZLib.Ada 1.2:
+
+- Attension: ZLib.Read generic routine have a initialization requirement
+  for Read_Last parameter now. It is a bit incompartible with previous version,
+  but extends functionality, we could use new parameters Allow_Read_Some and
+  Flush now.
+
+- Added Is_Open routines to ZLib and ZLib.Streams packages.
+
+- Add pragma Assert to check Stream_Element is 8 bit.
+
+- Fix extraction to buffer with exact known decompressed size. Error reported by
+  Steve Sangwine.
+
+- Fix definition of ULong (changed to unsigned_long), fix regression on 64 bits
+  computers. Patch provided by Pascal Obry.
+
+- Add Status_Error exception definition.
+
+- Add pragma Assertion that Ada.Streams.Stream_Element size is 8 bit.
+
+
+        How to build ZLib.Ada under GNAT
+
+You should have the ZLib library already build on your computer, before
+building ZLib.Ada. Make the directory of ZLib.Ada sources current and
+issue the command:
+
+  gnatmake test -largs -L<directory where libz.a is> -lz
+
+Or use the GNAT project file build for GNAT 3.15 or later:
+
+  gnatmake -Pzlib.gpr -L<directory where libz.a is>
+
+
+        How to build ZLib.Ada under Aonix ObjectAda for Win32 7.2.2
+
+1. Make a project with all *.ads and *.adb files from the distribution.
+2. Build the libz.a library from the ZLib C sources.
+3. Rename libz.a to z.lib.
+4. Add the library z.lib to the project.
+5. Add the libc.lib library from the ObjectAda distribution to the project.
+6. Build the executable using test.adb as a main procedure.
+
+
+        How to use ZLib.Ada
+
+The source files test.adb and read.adb are small demo programs that show
+the main functionality of ZLib.Ada.
+
+The routines from the package specifications are commented.
+
+
+Homepage: http://zlib-ada.sourceforge.net/
+Author: Dmitriy Anisimkov <anisimkov@yahoo.com>
+
+Contributors: Pascal Obry <pascal@obry.org>, Steve Sangwine <sjs@essex.ac.uk>
diff --git a/gs/zlib/contrib/ada/test.adb b/gs/zlib/contrib/ada/test.adb
new file mode 100644
index 000000000..90773acfa
--- /dev/null
+++ b/gs/zlib/contrib/ada/test.adb
@@ -0,0 +1,463 @@
+----------------------------------------------------------------
+--  ZLib for Ada thick binding.                               --
+--                                                            --
+--  Copyright (C) 2002-2003 Dmitriy Anisimkov                 --
+--                                                            --
+--  Open source license information is in the zlib.ads file.  --
+----------------------------------------------------------------
+
+--  $Id: test.adb,v 1.17 2003/08/12 12:13:30 vagul Exp $
+
+--  The program has a few aims.
+--  1. Test ZLib.Ada95 thick binding functionality.
+--  2. Show the example of use main functionality of the ZLib.Ada95 binding.
+--  3. Build this program automatically compile all ZLib.Ada95 packages under
+--     GNAT Ada95 compiler.
+
+with ZLib.Streams;
+with Ada.Streams.Stream_IO;
+with Ada.Numerics.Discrete_Random;
+
+with Ada.Text_IO;
+
+with Ada.Calendar;
+
+procedure Test is
+
+   use Ada.Streams;
+   use Stream_IO;
+
+   ------------------------------------
+   --  Test configuration parameters --
+   ------------------------------------
+
+   File_Size   : Count   := 100_000;
+   Continuous  : constant Boolean := False;
+
+   Header      : constant ZLib.Header_Type := ZLib.Default;
+                                              --  ZLib.None;
+                                              --  ZLib.Auto;
+                                              --  ZLib.GZip;
+   --  Do not use Header other then Default in ZLib versions 1.1.4
+   --  and older.
+
+   Strategy    : constant ZLib.Strategy_Type := ZLib.Default_Strategy;
+   Init_Random : constant := 10;
+
+   -- End --
+
+   In_File_Name  : constant String := "testzlib.in";
+   --  Name of the input file
+
+   Z_File_Name   : constant String := "testzlib.zlb";
+   --  Name of the compressed file.
+
+   Out_File_Name : constant String := "testzlib.out";
+   --  Name of the decompressed file.
+
+   File_In   : File_Type;
+   File_Out  : File_Type;
+   File_Back : File_Type;
+   File_Z    : ZLib.Streams.Stream_Type;
+
+   Filter : ZLib.Filter_Type;
+
+   Time_Stamp : Ada.Calendar.Time;
+
+   procedure Generate_File;
+   --  Generate file of spetsified size with some random data.
+   --  The random data is repeatable, for the good compression.
+
+   procedure Compare_Streams
+     (Left, Right : in out Root_Stream_Type'Class);
+   --  The procedure compearing data in 2 streams.
+   --  It is for compare data before and after compression/decompression.
+
+   procedure Compare_Files (Left, Right : String);
+   --  Compare files. Based on the Compare_Streams.
+
+   procedure Copy_Streams
+     (Source, Target : in out Root_Stream_Type'Class;
+      Buffer_Size    : in     Stream_Element_Offset := 1024);
+   --  Copying data from one stream to another. It is for test stream
+   --  interface of the library.
+
+   procedure Data_In
+     (Item : out Stream_Element_Array;
+      Last : out Stream_Element_Offset);
+   --  this procedure is for generic instantiation of
+   --  ZLib.Generic_Translate.
+   --  reading data from the File_In.
+
+   procedure Data_Out (Item : in Stream_Element_Array);
+   --  this procedure is for generic instantiation of
+   --  ZLib.Generic_Translate.
+   --  writing data to the File_Out.
+
+   procedure Stamp;
+   --  Store the timestamp to the local variable.
+
+   procedure Print_Statistic (Msg : String; Data_Size : ZLib.Count);
+   --  Print the time statistic with the message.
+
+   procedure Translate is new ZLib.Generic_Translate
+                                (Data_In  => Data_In,
+                                 Data_Out => Data_Out);
+   --  This procedure is moving data from File_In to File_Out
+   --  with compression or decompression, depend on initialization of
+   --  Filter parameter.
+
+   -------------------
+   -- Compare_Files --
+   -------------------
+
+   procedure Compare_Files (Left, Right : String) is
+      Left_File, Right_File : File_Type;
+   begin
+      Open (Left_File, In_File, Left);
+      Open (Right_File, In_File, Right);
+      Compare_Streams (Stream (Left_File).all, Stream (Right_File).all);
+      Close (Left_File);
+      Close (Right_File);
+   end Compare_Files;
+
+   ---------------------
+   -- Compare_Streams --
+   ---------------------
+
+   procedure Compare_Streams
+     (Left, Right : in out Ada.Streams.Root_Stream_Type'Class)
+   is
+      Left_Buffer, Right_Buffer : Stream_Element_Array (0 .. 16#FFF#);
+      Left_Last, Right_Last : Stream_Element_Offset;
+   begin
+      loop
+         Read (Left, Left_Buffer, Left_Last);
+         Read (Right, Right_Buffer, Right_Last);
+
+         if Left_Last /= Right_Last then
+            Ada.Text_IO.Put_Line ("Compare error :"
+              & Stream_Element_Offset'Image (Left_Last)
+              & " /= "
+              & Stream_Element_Offset'Image (Right_Last));
+
+            raise Constraint_Error;
+
+         elsif Left_Buffer (0 .. Left_Last)
+               /= Right_Buffer (0 .. Right_Last)
+         then
+            Ada.Text_IO.Put_Line ("ERROR: IN and OUT files is not equal.");
+            raise Constraint_Error;
+
+         end if;
+
+         exit when Left_Last < Left_Buffer'Last;
+      end loop;
+   end Compare_Streams;
+
+   ------------------
+   -- Copy_Streams --
+   ------------------
+
+   procedure Copy_Streams
+     (Source, Target : in out Ada.Streams.Root_Stream_Type'Class;
+      Buffer_Size    : in     Stream_Element_Offset := 1024)
+   is
+      Buffer : Stream_Element_Array (1 .. Buffer_Size);
+      Last   : Stream_Element_Offset;
+   begin
+      loop
+         Read  (Source, Buffer, Last);
+         Write (Target, Buffer (1 .. Last));
+
+         exit when Last < Buffer'Last;
+      end loop;
+   end Copy_Streams;
+
+   -------------
+   -- Data_In --
+   -------------
+
+   procedure Data_In
+     (Item : out Stream_Element_Array;
+      Last : out Stream_Element_Offset) is
+   begin
+      Read (File_In, Item, Last);
+   end Data_In;
+
+   --------------
+   -- Data_Out --
+   --------------
+
+   procedure Data_Out (Item : in Stream_Element_Array) is
+   begin
+      Write (File_Out, Item);
+   end Data_Out;
+
+   -------------------
+   -- Generate_File --
+   -------------------
+
+   procedure Generate_File is
+      subtype Visible_Symbols is Stream_Element range 16#20# .. 16#7E#;
+
+      package Random_Elements is
+         new Ada.Numerics.Discrete_Random (Visible_Symbols);
+
+      Gen    : Random_Elements.Generator;
+      Buffer : Stream_Element_Array := (1 .. 77 => 16#20#) & 10;
+
+      Buffer_Count : constant Count := File_Size / Buffer'Length;
+      --  Number of same buffers in the packet.
+
+      Density : constant Count := 30; --  from 0 to Buffer'Length - 2;
+
+      procedure Fill_Buffer (J, D : in Count);
+      --  Change the part of the buffer.
+
+      -----------------
+      -- Fill_Buffer --
+      -----------------
+
+      procedure Fill_Buffer (J, D : in Count) is
+      begin
+         for K in 0 .. D loop
+            Buffer
+              (Stream_Element_Offset ((J + K) mod (Buffer'Length - 1) + 1))
+             := Random_Elements.Random (Gen);
+
+         end loop;
+      end Fill_Buffer;
+
+   begin
+      Random_Elements.Reset (Gen, Init_Random);
+
+      Create (File_In, Out_File, In_File_Name);
+
+      Fill_Buffer (1, Buffer'Length - 2);
+
+      for J in 1 .. Buffer_Count loop
+         Write (File_In, Buffer);
+
+         Fill_Buffer (J, Density);
+      end loop;
+
+      --  fill remain size.
+
+      Write
+        (File_In,
+         Buffer
+           (1 .. Stream_Element_Offset
+                   (File_Size - Buffer'Length * Buffer_Count)));
+
+      Flush (File_In);
+      Close (File_In);
+   end Generate_File;
+
+   ---------------------
+   -- Print_Statistic --
+   ---------------------
+
+   procedure Print_Statistic (Msg : String; Data_Size : ZLib.Count) is
+      use Ada.Calendar;
+      use Ada.Text_IO;
+
+      package Count_IO is new Integer_IO (ZLib.Count);
+
+      Curr_Dur : Duration := Clock - Time_Stamp;
+   begin
+      Put (Msg);
+
+      Set_Col (20);
+      Ada.Text_IO.Put ("size =");
+
+      Count_IO.Put
+        (Data_Size,
+         Width => Stream_IO.Count'Image (File_Size)'Length);
+
+      Put_Line (" duration =" & Duration'Image (Curr_Dur));
+   end Print_Statistic;
+
+   -----------
+   -- Stamp --
+   -----------
+
+   procedure Stamp is
+   begin
+      Time_Stamp := Ada.Calendar.Clock;
+   end Stamp;
+
+begin
+   Ada.Text_IO.Put_Line ("ZLib " & ZLib.Version);
+
+   loop
+      Generate_File;
+
+      for Level in ZLib.Compression_Level'Range loop
+
+         Ada.Text_IO.Put_Line ("Level ="
+            & ZLib.Compression_Level'Image (Level));
+
+         --  Test generic interface.
+         Open   (File_In, In_File, In_File_Name);
+         Create (File_Out, Out_File, Z_File_Name);
+
+         Stamp;
+
+         --  Deflate using generic instantiation.
+
+         ZLib.Deflate_Init
+               (Filter   => Filter,
+                Level    => Level,
+                Strategy => Strategy,
+                Header   => Header);
+
+         Translate (Filter);
+         Print_Statistic ("Generic compress", ZLib.Total_Out (Filter));
+         ZLib.Close (Filter);
+
+         Close (File_In);
+         Close (File_Out);
+
+         Open   (File_In, In_File, Z_File_Name);
+         Create (File_Out, Out_File, Out_File_Name);
+
+         Stamp;
+
+         --  Inflate using generic instantiation.
+
+         ZLib.Inflate_Init (Filter, Header => Header);
+
+         Translate (Filter);
+         Print_Statistic ("Generic decompress", ZLib.Total_Out (Filter));
+
+         ZLib.Close (Filter);
+
+         Close (File_In);
+         Close (File_Out);
+
+         Compare_Files (In_File_Name, Out_File_Name);
+
+         --  Test stream interface.
+
+         --  Compress to the back stream.
+
+         Open   (File_In, In_File, In_File_Name);
+         Create (File_Back, Out_File, Z_File_Name);
+
+         Stamp;
+
+         ZLib.Streams.Create
+           (Stream          => File_Z,
+            Mode            => ZLib.Streams.Out_Stream,
+            Back            => ZLib.Streams.Stream_Access
+                                 (Stream (File_Back)),
+            Back_Compressed => True,
+            Level           => Level,
+            Strategy        => Strategy,
+            Header          => Header);
+
+         Copy_Streams
+           (Source => Stream (File_In).all,
+            Target => File_Z);
+
+         --  Flushing internal buffers to the back stream.
+
+         ZLib.Streams.Flush (File_Z, ZLib.Finish);
+
+         Print_Statistic ("Write compress",
+                          ZLib.Streams.Write_Total_Out (File_Z));
+
+         ZLib.Streams.Close (File_Z);
+
+         Close (File_In);
+         Close (File_Back);
+
+         --  Compare reading from original file and from
+         --  decompression stream.
+
+         Open (File_In,   In_File, In_File_Name);
+         Open (File_Back, In_File, Z_File_Name);
+
+         ZLib.Streams.Create
+           (Stream          => File_Z,
+            Mode            => ZLib.Streams.In_Stream,
+            Back            => ZLib.Streams.Stream_Access
+                                 (Stream (File_Back)),
+            Back_Compressed => True,
+            Header          => Header);
+
+         Stamp;
+         Compare_Streams (Stream (File_In).all, File_Z);
+
+         Print_Statistic ("Read decompress",
+                          ZLib.Streams.Read_Total_Out (File_Z));
+
+         ZLib.Streams.Close (File_Z);
+         Close (File_In);
+         Close (File_Back);
+
+         --  Compress by reading from compression stream.
+
+         Open (File_Back, In_File, In_File_Name);
+         Create (File_Out, Out_File, Z_File_Name);
+
+         ZLib.Streams.Create
+           (Stream          => File_Z,
+            Mode            => ZLib.Streams.In_Stream,
+            Back            => ZLib.Streams.Stream_Access
+                                 (Stream (File_Back)),
+            Back_Compressed => False,
+            Level           => Level,
+            Strategy        => Strategy,
+            Header          => Header);
+
+         Stamp;
+         Copy_Streams
+           (Source => File_Z,
+            Target => Stream (File_Out).all);
+
+         Print_Statistic ("Read compress",
+                          ZLib.Streams.Read_Total_Out (File_Z));
+
+         ZLib.Streams.Close (File_Z);
+
+         Close (File_Out);
+         Close (File_Back);
+
+         --  Decompress to decompression stream.
+
+         Open   (File_In,   In_File, Z_File_Name);
+         Create (File_Back, Out_File, Out_File_Name);
+
+         ZLib.Streams.Create
+           (Stream          => File_Z,
+            Mode            => ZLib.Streams.Out_Stream,
+            Back            => ZLib.Streams.Stream_Access
+                                 (Stream (File_Back)),
+            Back_Compressed => False,
+            Header          => Header);
+
+         Stamp;
+
+         Copy_Streams
+           (Source => Stream (File_In).all,
+            Target => File_Z);
+
+         Print_Statistic ("Write decompress",
+                          ZLib.Streams.Write_Total_Out (File_Z));
+
+         ZLib.Streams.Close (File_Z);
+         Close (File_In);
+         Close (File_Back);
+
+         Compare_Files (In_File_Name, Out_File_Name);
+      end loop;
+
+      Ada.Text_IO.Put_Line (Count'Image (File_Size) & " Ok.");
+
+      exit when not Continuous;
+
+      File_Size := File_Size + 1;
+   end loop;
+end Test;
diff --git a/gs/zlib/contrib/ada/zlib-streams.adb b/gs/zlib/contrib/ada/zlib-streams.adb
new file mode 100644
index 000000000..b6497bae2
--- /dev/null
+++ b/gs/zlib/contrib/ada/zlib-streams.adb
@@ -0,0 +1,225 @@
+----------------------------------------------------------------
+--  ZLib for Ada thick binding.                               --
+--                                                            --
+--  Copyright (C) 2002-2003 Dmitriy Anisimkov                 --
+--                                                            --
+--  Open source license information is in the zlib.ads file.  --
+----------------------------------------------------------------
+
+--  $Id: zlib-streams.adb,v 1.10 2004/05/31 10:53:40 vagul Exp $
+
+with Ada.Unchecked_Deallocation;
+
+package body ZLib.Streams is
+
+   -----------
+   -- Close --
+   -----------
+
+   procedure Close (Stream : in out Stream_Type) is
+      procedure Free is new Ada.Unchecked_Deallocation
+         (Stream_Element_Array, Buffer_Access);
+   begin
+      if Stream.Mode = Out_Stream or Stream.Mode = Duplex then
+         --  We should flush the data written by the writer.
+
+         Flush (Stream, Finish);
+
+         Close (Stream.Writer);
+      end if;
+
+      if Stream.Mode = In_Stream or Stream.Mode = Duplex then
+         Close (Stream.Reader);
+         Free (Stream.Buffer);
+      end if;
+   end Close;
+
+   ------------
+   -- Create --
+   ------------
+
+   procedure Create
+     (Stream            :    out Stream_Type;
+      Mode              : in     Stream_Mode;
+      Back              : in     Stream_Access;
+      Back_Compressed   : in     Boolean;
+      Level             : in     Compression_Level := Default_Compression;
+      Strategy          : in     Strategy_Type     := Default_Strategy;
+      Header            : in     Header_Type       := Default;
+      Read_Buffer_Size  : in     Ada.Streams.Stream_Element_Offset
+                                    := Default_Buffer_Size;
+      Write_Buffer_Size : in     Ada.Streams.Stream_Element_Offset
+                                    := Default_Buffer_Size)
+   is
+
+      subtype Buffer_Subtype is Stream_Element_Array (1 .. Read_Buffer_Size);
+
+      procedure Init_Filter
+         (Filter   : in out Filter_Type;
+          Compress : in     Boolean);
+
+      -----------------
+      -- Init_Filter --
+      -----------------
+
+      procedure Init_Filter
+         (Filter   : in out Filter_Type;
+          Compress : in     Boolean) is
+      begin
+         if Compress then
+            Deflate_Init
+              (Filter, Level, Strategy, Header => Header);
+         else
+            Inflate_Init (Filter, Header => Header);
+         end if;
+      end Init_Filter;
+
+   begin
+      Stream.Back := Back;
+      Stream.Mode := Mode;
+
+      if Mode = Out_Stream or Mode = Duplex then
+         Init_Filter (Stream.Writer, Back_Compressed);
+         Stream.Buffer_Size := Write_Buffer_Size;
+      else
+         Stream.Buffer_Size := 0;
+      end if;
+
+      if Mode = In_Stream or Mode = Duplex then
+         Init_Filter (Stream.Reader, not Back_Compressed);
+
+         Stream.Buffer     := new Buffer_Subtype;
+         Stream.Rest_First := Stream.Buffer'Last + 1;
+         Stream.Rest_Last  := Stream.Buffer'Last;
+      end if;
+   end Create;
+
+   -----------
+   -- Flush --
+   -----------
+
+   procedure Flush
+     (Stream : in out Stream_Type;
+      Mode   : in     Flush_Mode := Sync_Flush)
+   is
+      Buffer : Stream_Element_Array (1 .. Stream.Buffer_Size);
+      Last   : Stream_Element_Offset;
+   begin
+      loop
+         Flush (Stream.Writer, Buffer, Last, Mode);
+
+         Ada.Streams.Write (Stream.Back.all, Buffer (1 .. Last));
+
+         exit when Last < Buffer'Last;
+      end loop;
+   end Flush;
+
+   -------------
+   -- Is_Open --
+   -------------
+
+   function Is_Open (Stream : Stream_Type) return Boolean is
+   begin
+      return Is_Open (Stream.Reader) or else Is_Open (Stream.Writer);
+   end Is_Open;
+
+   ----------
+   -- Read --
+   ----------
+
+   procedure Read
+     (Stream : in out Stream_Type;
+      Item   :    out Stream_Element_Array;
+      Last   :    out Stream_Element_Offset)
+   is
+
+      procedure Read
+        (Item : out Stream_Element_Array;
+         Last : out Stream_Element_Offset);
+
+      ----------
+      -- Read --
+      ----------
+
+      procedure Read
+        (Item : out Stream_Element_Array;
+         Last : out Stream_Element_Offset) is
+      begin
+         Ada.Streams.Read (Stream.Back.all, Item, Last);
+      end Read;
+
+      procedure Read is new ZLib.Read
+         (Read       => Read,
+          Buffer     => Stream.Buffer.all,
+          Rest_First => Stream.Rest_First,
+          Rest_Last  => Stream.Rest_Last);
+
+   begin
+      Read (Stream.Reader, Item, Last);
+   end Read;
+
+   -------------------
+   -- Read_Total_In --
+   -------------------
+
+   function Read_Total_In (Stream : in Stream_Type) return Count is
+   begin
+      return Total_In (Stream.Reader);
+   end Read_Total_In;
+
+   --------------------
+   -- Read_Total_Out --
+   --------------------
+
+   function Read_Total_Out (Stream : in Stream_Type) return Count is
+   begin
+      return Total_Out (Stream.Reader);
+   end Read_Total_Out;
+
+   -----------
+   -- Write --
+   -----------
+
+   procedure Write
+     (Stream : in out Stream_Type;
+      Item   : in     Stream_Element_Array)
+   is
+
+      procedure Write (Item : in Stream_Element_Array);
+
+      -----------
+      -- Write --
+      -----------
+
+      procedure Write (Item : in Stream_Element_Array) is
+      begin
+         Ada.Streams.Write (Stream.Back.all, Item);
+      end Write;
+
+      procedure Write is new ZLib.Write
+         (Write       => Write,
+          Buffer_Size => Stream.Buffer_Size);
+
+   begin
+      Write (Stream.Writer, Item, No_Flush);
+   end Write;
+
+   --------------------
+   -- Write_Total_In --
+   --------------------
+
+   function Write_Total_In (Stream : in Stream_Type) return Count is
+   begin
+      return Total_In (Stream.Writer);
+   end Write_Total_In;
+
+   ---------------------
+   -- Write_Total_Out --
+   ---------------------
+
+   function Write_Total_Out (Stream : in Stream_Type) return Count is
+   begin
+      return Total_Out (Stream.Writer);
+   end Write_Total_Out;
+
+end ZLib.Streams;
diff --git a/gs/zlib/contrib/ada/zlib-streams.ads b/gs/zlib/contrib/ada/zlib-streams.ads
new file mode 100644
index 000000000..f0193c6ba
--- /dev/null
+++ b/gs/zlib/contrib/ada/zlib-streams.ads
@@ -0,0 +1,114 @@
+----------------------------------------------------------------
+--  ZLib for Ada thick binding.                               --
+--                                                            --
+--  Copyright (C) 2002-2003 Dmitriy Anisimkov                 --
+--                                                            --
+--  Open source license information is in the zlib.ads file.  --
+----------------------------------------------------------------
+
+--  $Id: zlib-streams.ads,v 1.12 2004/05/31 10:53:40 vagul Exp $
+
+package ZLib.Streams is
+
+   type Stream_Mode is (In_Stream, Out_Stream, Duplex);
+
+   type Stream_Access is access all Ada.Streams.Root_Stream_Type'Class;
+
+   type Stream_Type is
+      new Ada.Streams.Root_Stream_Type with private;
+
+   procedure Read
+     (Stream : in out Stream_Type;
+      Item   :    out Ada.Streams.Stream_Element_Array;
+      Last   :    out Ada.Streams.Stream_Element_Offset);
+
+   procedure Write
+     (Stream : in out Stream_Type;
+      Item   : in     Ada.Streams.Stream_Element_Array);
+
+   procedure Flush
+     (Stream : in out Stream_Type;
+      Mode   : in     Flush_Mode := Sync_Flush);
+   --  Flush the written data to the back stream,
+   --  all data placed to the compressor is flushing to the Back stream.
+   --  Should not be used untill necessary, becouse it is decreasing
+   --  compression.
+
+   function Read_Total_In (Stream : in Stream_Type) return Count;
+   pragma Inline (Read_Total_In);
+   --  Return total number of bytes read from back stream so far.
+
+   function Read_Total_Out (Stream : in Stream_Type) return Count;
+   pragma Inline (Read_Total_Out);
+   --  Return total number of bytes read so far.
+
+   function Write_Total_In (Stream : in Stream_Type) return Count;
+   pragma Inline (Write_Total_In);
+   --  Return total number of bytes written so far.
+
+   function Write_Total_Out (Stream : in Stream_Type) return Count;
+   pragma Inline (Write_Total_Out);
+   --  Return total number of bytes written to the back stream.
+
+   procedure Create
+     (Stream            :    out Stream_Type;
+      Mode              : in     Stream_Mode;
+      Back              : in     Stream_Access;
+      Back_Compressed   : in     Boolean;
+      Level             : in     Compression_Level := Default_Compression;
+      Strategy          : in     Strategy_Type     := Default_Strategy;
+      Header            : in     Header_Type       := Default;
+      Read_Buffer_Size  : in     Ada.Streams.Stream_Element_Offset
+                                    := Default_Buffer_Size;
+      Write_Buffer_Size : in     Ada.Streams.Stream_Element_Offset
+                                    := Default_Buffer_Size);
+   --  Create the Comression/Decompression stream.
+   --  If mode is In_Stream then Write operation is disabled.
+   --  If mode is Out_Stream then Read operation is disabled.
+
+   --  If Back_Compressed is true then
+   --  Data written to the Stream is compressing to the Back stream
+   --  and data read from the Stream is decompressed data from the Back stream.
+
+   --  If Back_Compressed is false then
+   --  Data written to the Stream is decompressing to the Back stream
+   --  and data read from the Stream is compressed data from the Back stream.
+
+   --  !!! When the Need_Header is False ZLib-Ada is using undocumented
+   --  ZLib 1.1.4 functionality to do not create/wait for ZLib headers.
+
+   function Is_Open (Stream : Stream_Type) return Boolean;
+
+   procedure Close (Stream : in out Stream_Type);
+
+private
+
+   use Ada.Streams;
+
+   type Buffer_Access is access all Stream_Element_Array;
+
+   type Stream_Type
+     is new Root_Stream_Type with
+   record
+      Mode       : Stream_Mode;
+
+      Buffer     : Buffer_Access;
+      Rest_First : Stream_Element_Offset;
+      Rest_Last  : Stream_Element_Offset;
+      --  Buffer for Read operation.
+      --  We need to have this buffer in the record
+      --  becouse not all read data from back stream
+      --  could be processed during the read operation.
+
+      Buffer_Size : Stream_Element_Offset;
+      --  Buffer size for write operation.
+      --  We do not need to have this buffer
+      --  in the record becouse all data could be
+      --  processed in the write operation.
+
+      Back       : Stream_Access;
+      Reader     : Filter_Type;
+      Writer     : Filter_Type;
+   end record;
+
+end ZLib.Streams;
diff --git a/gs/zlib/contrib/ada/zlib-thin.adb b/gs/zlib/contrib/ada/zlib-thin.adb
new file mode 100644
index 000000000..0ca4a7120
--- /dev/null
+++ b/gs/zlib/contrib/ada/zlib-thin.adb
@@ -0,0 +1,141 @@
+----------------------------------------------------------------
+--  ZLib for Ada thick binding.                               --
+--                                                            --
+--  Copyright (C) 2002-2003 Dmitriy Anisimkov                 --
+--                                                            --
+--  Open source license information is in the zlib.ads file.  --
+----------------------------------------------------------------
+
+--  $Id: zlib-thin.adb,v 1.8 2003/12/14 18:27:31 vagul Exp $
+
+package body ZLib.Thin is
+
+   ZLIB_VERSION  : constant Chars_Ptr := zlibVersion;
+
+   Z_Stream_Size : constant Int := Z_Stream'Size / System.Storage_Unit;
+
+   --------------
+   -- Avail_In --
+   --------------
+
+   function Avail_In (Strm : in Z_Stream) return UInt is
+   begin
+      return Strm.Avail_In;
+   end Avail_In;
+
+   ---------------
+   -- Avail_Out --
+   ---------------
+
+   function Avail_Out (Strm : in Z_Stream) return UInt is
+   begin
+      return Strm.Avail_Out;
+   end Avail_Out;
+
+   ------------------
+   -- Deflate_Init --
+   ------------------
+
+   function Deflate_Init
+     (strm       : Z_Streamp;
+      level      : Int;
+      method     : Int;
+      windowBits : Int;
+      memLevel   : Int;
+      strategy   : Int)
+      return       Int is
+   begin
+      return deflateInit2
+               (strm,
+                level,
+                method,
+                windowBits,
+                memLevel,
+                strategy,
+                ZLIB_VERSION,
+                Z_Stream_Size);
+   end Deflate_Init;
+
+   ------------------
+   -- Inflate_Init --
+   ------------------
+
+   function Inflate_Init (strm : Z_Streamp; windowBits : Int) return Int is
+   begin
+      return inflateInit2 (strm, windowBits, ZLIB_VERSION, Z_Stream_Size);
+   end Inflate_Init;
+
+   ------------------------
+   -- Last_Error_Message --
+   ------------------------
+
+   function Last_Error_Message (Strm : in Z_Stream) return String is
+      use Interfaces.C.Strings;
+   begin
+      if Strm.msg = Null_Ptr then
+         return "";
+      else
+         return Value (Strm.msg);
+      end if;
+   end Last_Error_Message;
+
+   ------------
+   -- Set_In --
+   ------------
+
+   procedure Set_In
+     (Strm   : in out Z_Stream;
+      Buffer : in     Voidp;
+      Size   : in     UInt) is
+   begin
+      Strm.Next_In  := Buffer;
+      Strm.Avail_In := Size;
+   end Set_In;
+
+   ------------------
+   -- Set_Mem_Func --
+   ------------------
+
+   procedure Set_Mem_Func
+     (Strm   : in out Z_Stream;
+      Opaque : in     Voidp;
+      Alloc  : in     alloc_func;
+      Free   : in     free_func) is
+   begin
+      Strm.opaque := Opaque;
+      Strm.zalloc := Alloc;
+      Strm.zfree  := Free;
+   end Set_Mem_Func;
+
+   -------------
+   -- Set_Out --
+   -------------
+
+   procedure Set_Out
+     (Strm   : in out Z_Stream;
+      Buffer : in     Voidp;
+      Size   : in     UInt) is
+   begin
+      Strm.Next_Out  := Buffer;
+      Strm.Avail_Out := Size;
+   end Set_Out;
+
+   --------------
+   -- Total_In --
+   --------------
+
+   function Total_In (Strm : in Z_Stream) return ULong is
+   begin
+      return Strm.Total_In;
+   end Total_In;
+
+   ---------------
+   -- Total_Out --
+   ---------------
+
+   function Total_Out (Strm : in Z_Stream) return ULong is
+   begin
+      return Strm.Total_Out;
+   end Total_Out;
+
+end ZLib.Thin;
diff --git a/gs/zlib/contrib/ada/zlib-thin.ads b/gs/zlib/contrib/ada/zlib-thin.ads
new file mode 100644
index 000000000..d4407eb80
--- /dev/null
+++ b/gs/zlib/contrib/ada/zlib-thin.ads
@@ -0,0 +1,450 @@
+----------------------------------------------------------------
+--  ZLib for Ada thick binding.                               --
+--                                                            --
+--  Copyright (C) 2002-2003 Dmitriy Anisimkov                 --
+--                                                            --
+--  Open source license information is in the zlib.ads file.  --
+----------------------------------------------------------------
+
+--  $Id: zlib-thin.ads,v 1.11 2004/07/23 06:33:11 vagul Exp $
+
+with Interfaces.C.Strings;
+
+with System;
+
+private package ZLib.Thin is
+
+   --  From zconf.h
+
+   MAX_MEM_LEVEL : constant := 9;         --  zconf.h:105
+                                          --  zconf.h:105
+   MAX_WBITS : constant := 15;      --  zconf.h:115
+                                    --  32K LZ77 window
+                                    --  zconf.h:115
+   SEEK_SET : constant := 8#0000#;  --  zconf.h:244
+                                    --  Seek from beginning of file.
+                                    --  zconf.h:244
+   SEEK_CUR : constant := 1;        --  zconf.h:245
+                                    --  Seek from current position.
+                                    --  zconf.h:245
+   SEEK_END : constant := 2;        --  zconf.h:246
+                                    --  Set file pointer to EOF plus "offset"
+                                    --  zconf.h:246
+
+   type Byte is new Interfaces.C.unsigned_char; --  8 bits
+                                                --  zconf.h:214
+   type UInt is new Interfaces.C.unsigned;      --  16 bits or more
+                                                --  zconf.h:216
+   type Int is new Interfaces.C.int;
+
+   type ULong is new Interfaces.C.unsigned_long;     --  32 bits or more
+                                                     --  zconf.h:217
+   subtype Chars_Ptr is Interfaces.C.Strings.chars_ptr;
+
+   type ULong_Access is access ULong;
+   type Int_Access is access Int;
+
+   subtype Voidp is System.Address;            --  zconf.h:232
+
+   subtype Byte_Access is Voidp;
+
+   Nul : constant Voidp := System.Null_Address;
+   --  end from zconf
+
+   Z_NO_FLUSH : constant := 8#0000#;   --  zlib.h:125
+                                       --  zlib.h:125
+   Z_PARTIAL_FLUSH : constant := 1;       --  zlib.h:126
+                                          --  will be removed, use
+                                          --  Z_SYNC_FLUSH instead
+                                          --  zlib.h:126
+   Z_SYNC_FLUSH : constant := 2;       --  zlib.h:127
+                                       --  zlib.h:127
+   Z_FULL_FLUSH : constant := 3;       --  zlib.h:128
+                                       --  zlib.h:128
+   Z_FINISH : constant := 4;        --  zlib.h:129
+                                    --  zlib.h:129
+   Z_OK : constant := 8#0000#;   --  zlib.h:132
+                                 --  zlib.h:132
+   Z_STREAM_END : constant := 1;       --  zlib.h:133
+                                       --  zlib.h:133
+   Z_NEED_DICT : constant := 2;        --  zlib.h:134
+                                       --  zlib.h:134
+   Z_ERRNO : constant := -1;        --  zlib.h:135
+                                    --  zlib.h:135
+   Z_STREAM_ERROR : constant := -2;       --  zlib.h:136
+                                          --  zlib.h:136
+   Z_DATA_ERROR : constant := -3;      --  zlib.h:137
+                                       --  zlib.h:137
+   Z_MEM_ERROR : constant := -4;       --  zlib.h:138
+                                       --  zlib.h:138
+   Z_BUF_ERROR : constant := -5;       --  zlib.h:139
+                                       --  zlib.h:139
+   Z_VERSION_ERROR : constant := -6;      --  zlib.h:140
+                                          --  zlib.h:140
+   Z_NO_COMPRESSION : constant := 8#0000#;   --  zlib.h:145
+                                             --  zlib.h:145
+   Z_BEST_SPEED : constant := 1;       --  zlib.h:146
+                                       --  zlib.h:146
+   Z_BEST_COMPRESSION : constant := 9;       --  zlib.h:147
+                                             --  zlib.h:147
+   Z_DEFAULT_COMPRESSION : constant := -1;      --  zlib.h:148
+                                                --  zlib.h:148
+   Z_FILTERED : constant := 1;      --  zlib.h:151
+                                    --  zlib.h:151
+   Z_HUFFMAN_ONLY : constant := 2;        --  zlib.h:152
+                                          --  zlib.h:152
+   Z_DEFAULT_STRATEGY : constant := 8#0000#; --  zlib.h:153
+                                             --  zlib.h:153
+   Z_BINARY : constant := 8#0000#;  --  zlib.h:156
+                                    --  zlib.h:156
+   Z_ASCII : constant := 1;      --  zlib.h:157
+                                 --  zlib.h:157
+   Z_UNKNOWN : constant := 2;       --  zlib.h:158
+                                    --  zlib.h:158
+   Z_DEFLATED : constant := 8;      --  zlib.h:161
+                                    --  zlib.h:161
+   Z_NULL : constant := 8#0000#; --  zlib.h:164
+                                 --  for initializing zalloc, zfree, opaque
+                                 --  zlib.h:164
+   type gzFile is new Voidp;                  --  zlib.h:646
+
+   type Z_Stream is private;
+
+   type Z_Streamp is access all Z_Stream;     --  zlib.h:89
+
+   type alloc_func is access function
+     (Opaque : Voidp;
+      Items  : UInt;
+      Size   : UInt)
+      return Voidp; --  zlib.h:63
+
+   type free_func is access procedure (opaque : Voidp; address : Voidp);
+
+   function zlibVersion return Chars_Ptr;
+
+   function Deflate (strm : Z_Streamp; flush : Int) return Int;
+
+   function DeflateEnd (strm : Z_Streamp) return Int;
+
+   function Inflate (strm : Z_Streamp; flush : Int) return Int;
+
+   function InflateEnd (strm : Z_Streamp) return Int;
+
+   function deflateSetDictionary
+     (strm       : Z_Streamp;
+      dictionary : Byte_Access;
+      dictLength : UInt)
+      return       Int;
+
+   function deflateCopy (dest : Z_Streamp; source : Z_Streamp) return Int;
+   --  zlib.h:478
+
+   function deflateReset (strm : Z_Streamp) return Int; -- zlib.h:495
+
+   function deflateParams
+     (strm     : Z_Streamp;
+      level    : Int;
+      strategy : Int)
+      return     Int;       -- zlib.h:506
+
+   function inflateSetDictionary
+     (strm       : Z_Streamp;
+      dictionary : Byte_Access;
+      dictLength : UInt)
+      return       Int; --  zlib.h:548
+
+   function inflateSync (strm : Z_Streamp) return Int;  --  zlib.h:565
+
+   function inflateReset (strm : Z_Streamp) return Int; --  zlib.h:580
+
+   function compress
+     (dest      : Byte_Access;
+      destLen   : ULong_Access;
+      source    : Byte_Access;
+      sourceLen : ULong)
+      return      Int;           -- zlib.h:601
+
+   function compress2
+     (dest      : Byte_Access;
+      destLen   : ULong_Access;
+      source    : Byte_Access;
+      sourceLen : ULong;
+      level     : Int)
+      return      Int;          -- zlib.h:615
+
+   function uncompress
+     (dest      : Byte_Access;
+      destLen   : ULong_Access;
+      source    : Byte_Access;
+      sourceLen : ULong)
+      return      Int;
+
+   function gzopen (path : Chars_Ptr; mode : Chars_Ptr) return gzFile;
+
+   function gzdopen (fd : Int; mode : Chars_Ptr) return gzFile;
+
+   function gzsetparams
+     (file     : gzFile;
+      level    : Int;
+      strategy : Int)
+      return     Int;
+
+   function gzread
+     (file : gzFile;
+      buf  : Voidp;
+      len  : UInt)
+      return Int;
+
+   function gzwrite
+     (file : in gzFile;
+      buf  : in Voidp;
+      len  : in UInt)
+      return Int;
+
+   function gzprintf (file : in gzFile; format : in Chars_Ptr) return Int;
+
+   function gzputs (file : in gzFile; s : in Chars_Ptr) return Int;
+
+   function gzgets
+     (file : gzFile;
+      buf  : Chars_Ptr;
+      len  : Int)
+      return Chars_Ptr;
+
+   function gzputc (file : gzFile; char : Int) return Int;
+
+   function gzgetc (file : gzFile) return Int;
+
+   function gzflush (file : gzFile; flush : Int) return Int;
+
+   function gzseek
+     (file   : gzFile;
+      offset : Int;
+      whence : Int)
+      return   Int;
+
+   function gzrewind (file : gzFile) return Int;
+
+   function gztell (file : gzFile) return Int;
+
+   function gzeof (file : gzFile) return Int;
+
+   function gzclose (file : gzFile) return Int;
+
+   function gzerror (file : gzFile; errnum : Int_Access) return Chars_Ptr;
+
+   function adler32
+     (adler : ULong;
+      buf   : Byte_Access;
+      len   : UInt)
+      return  ULong;
+
+   function crc32
+     (crc  : ULong;
+      buf  : Byte_Access;
+      len  : UInt)
+      return ULong;
+
+   function deflateInit
+     (strm        : Z_Streamp;
+      level       : Int;
+      version     : Chars_Ptr;
+      stream_size : Int)
+      return        Int;
+
+   function deflateInit2
+     (strm        : Z_Streamp;
+      level       : Int;
+      method      : Int;
+      windowBits  : Int;
+      memLevel    : Int;
+      strategy    : Int;
+      version     : Chars_Ptr;
+      stream_size : Int)
+      return        Int;
+
+   function Deflate_Init
+     (strm       : Z_Streamp;
+      level      : Int;
+      method     : Int;
+      windowBits : Int;
+      memLevel   : Int;
+      strategy   : Int)
+      return       Int;
+   pragma Inline (Deflate_Init);
+
+   function inflateInit
+     (strm        : Z_Streamp;
+      version     : Chars_Ptr;
+      stream_size : Int)
+      return        Int;
+
+   function inflateInit2
+     (strm        : in Z_Streamp;
+      windowBits  : in Int;
+      version     : in Chars_Ptr;
+      stream_size : in Int)
+      return      Int;
+
+   function inflateBackInit
+     (strm        : in Z_Streamp;
+      windowBits  : in Int;
+      window      : in Byte_Access;
+      version     : in Chars_Ptr;
+      stream_size : in Int)
+      return      Int;
+   --  Size of window have to be 2**windowBits.
+
+   function Inflate_Init (strm : Z_Streamp; windowBits : Int) return Int;
+   pragma Inline (Inflate_Init);
+
+   function zError (err : Int) return Chars_Ptr;
+
+   function inflateSyncPoint (z : Z_Streamp) return Int;
+
+   function get_crc_table return ULong_Access;
+
+   --  Interface to the available fields of the z_stream structure.
+   --  The application must update next_in and avail_in when avail_in has
+   --  dropped to zero. It must update next_out and avail_out when avail_out
+   --  has dropped to zero. The application must initialize zalloc, zfree and
+   --  opaque before calling the init function.
+
+   procedure Set_In
+     (Strm   : in out Z_Stream;
+      Buffer : in Voidp;
+      Size   : in UInt);
+   pragma Inline (Set_In);
+
+   procedure Set_Out
+     (Strm   : in out Z_Stream;
+      Buffer : in Voidp;
+      Size   : in UInt);
+   pragma Inline (Set_Out);
+
+   procedure Set_Mem_Func
+     (Strm   : in out Z_Stream;
+      Opaque : in Voidp;
+      Alloc  : in alloc_func;
+      Free   : in free_func);
+   pragma Inline (Set_Mem_Func);
+
+   function Last_Error_Message (Strm : in Z_Stream) return String;
+   pragma Inline (Last_Error_Message);
+
+   function Avail_Out (Strm : in Z_Stream) return UInt;
+   pragma Inline (Avail_Out);
+
+   function Avail_In (Strm : in Z_Stream) return UInt;
+   pragma Inline (Avail_In);
+
+   function Total_In (Strm : in Z_Stream) return ULong;
+   pragma Inline (Total_In);
+
+   function Total_Out (Strm : in Z_Stream) return ULong;
+   pragma Inline (Total_Out);
+
+   function inflateCopy
+     (dest   : in Z_Streamp;
+      Source : in Z_Streamp)
+      return Int;
+
+   function compressBound (Source_Len : in ULong) return ULong;
+
+   function deflateBound
+     (Strm       : in Z_Streamp;
+      Source_Len : in ULong)
+      return     ULong;
+
+   function gzungetc (C : in Int; File : in  gzFile) return Int;
+
+   function zlibCompileFlags return ULong;
+
+private
+
+   type Z_Stream is record            -- zlib.h:68
+      Next_In   : Voidp      := Nul;  -- next input byte
+      Avail_In  : UInt       := 0;    -- number of bytes available at next_in
+      Total_In  : ULong      := 0;    -- total nb of input bytes read so far
+      Next_Out  : Voidp      := Nul;  -- next output byte should be put there
+      Avail_Out : UInt       := 0;    -- remaining free space at next_out
+      Total_Out : ULong      := 0;    -- total nb of bytes output so far
+      msg       : Chars_Ptr;          -- last error message, NULL if no error
+      state     : Voidp;              -- not visible by applications
+      zalloc    : alloc_func := null; -- used to allocate the internal state
+      zfree     : free_func  := null; -- used to free the internal state
+      opaque    : Voidp;              -- private data object passed to
+                                      --  zalloc and zfree
+      data_type : Int;                -- best guess about the data type:
+                                      --  ascii or binary
+      adler     : ULong;              -- adler32 value of the uncompressed
+                                      --  data
+      reserved  : ULong;              -- reserved for future use
+   end record;
+
+   pragma Convention (C, Z_Stream);
+
+   pragma Import (C, zlibVersion, "zlibVersion");
+   pragma Import (C, Deflate, "deflate");
+   pragma Import (C, DeflateEnd, "deflateEnd");
+   pragma Import (C, Inflate, "inflate");
+   pragma Import (C, InflateEnd, "inflateEnd");
+   pragma Import (C, deflateSetDictionary, "deflateSetDictionary");
+   pragma Import (C, deflateCopy, "deflateCopy");
+   pragma Import (C, deflateReset, "deflateReset");
+   pragma Import (C, deflateParams, "deflateParams");
+   pragma Import (C, inflateSetDictionary, "inflateSetDictionary");
+   pragma Import (C, inflateSync, "inflateSync");
+   pragma Import (C, inflateReset, "inflateReset");
+   pragma Import (C, compress, "compress");
+   pragma Import (C, compress2, "compress2");
+   pragma Import (C, uncompress, "uncompress");
+   pragma Import (C, gzopen, "gzopen");
+   pragma Import (C, gzdopen, "gzdopen");
+   pragma Import (C, gzsetparams, "gzsetparams");
+   pragma Import (C, gzread, "gzread");
+   pragma Import (C, gzwrite, "gzwrite");
+   pragma Import (C, gzprintf, "gzprintf");
+   pragma Import (C, gzputs, "gzputs");
+   pragma Import (C, gzgets, "gzgets");
+   pragma Import (C, gzputc, "gzputc");
+   pragma Import (C, gzgetc, "gzgetc");
+   pragma Import (C, gzflush, "gzflush");
+   pragma Import (C, gzseek, "gzseek");
+   pragma Import (C, gzrewind, "gzrewind");
+   pragma Import (C, gztell, "gztell");
+   pragma Import (C, gzeof, "gzeof");
+   pragma Import (C, gzclose, "gzclose");
+   pragma Import (C, gzerror, "gzerror");
+   pragma Import (C, adler32, "adler32");
+   pragma Import (C, crc32, "crc32");
+   pragma Import (C, deflateInit, "deflateInit_");
+   pragma Import (C, inflateInit, "inflateInit_");
+   pragma Import (C, deflateInit2, "deflateInit2_");
+   pragma Import (C, inflateInit2, "inflateInit2_");
+   pragma Import (C, zError, "zError");
+   pragma Import (C, inflateSyncPoint, "inflateSyncPoint");
+   pragma Import (C, get_crc_table, "get_crc_table");
+
+   --  since zlib 1.2.0:
+
+   pragma Import (C, inflateCopy, "inflateCopy");
+   pragma Import (C, compressBound, "compressBound");
+   pragma Import (C, deflateBound, "deflateBound");
+   pragma Import (C, gzungetc, "gzungetc");
+   pragma Import (C, zlibCompileFlags, "zlibCompileFlags");
+
+   pragma Import (C, inflateBackInit, "inflateBackInit_");
+
+   --  I stopped binding the inflateBack routines, becouse realize that
+   --  it does not support zlib and gzip headers for now, and have no
+   --  symmetric deflateBack routines.
+   --  ZLib-Ada is symmetric regarding deflate/inflate data transformation
+   --  and has a similar generic callback interface for the
+   --  deflate/inflate transformation based on the regular Deflate/Inflate
+   --  routines.
+
+   --  pragma Import (C, inflateBack, "inflateBack");
+   --  pragma Import (C, inflateBackEnd, "inflateBackEnd");
+
+end ZLib.Thin;
diff --git a/gs/zlib/contrib/ada/zlib.adb b/gs/zlib/contrib/ada/zlib.adb
new file mode 100644
index 000000000..8b6fd686a
--- /dev/null
+++ b/gs/zlib/contrib/ada/zlib.adb
@@ -0,0 +1,701 @@
+----------------------------------------------------------------
+--  ZLib for Ada thick binding.                               --
+--                                                            --
+--  Copyright (C) 2002-2004 Dmitriy Anisimkov                 --
+--                                                            --
+--  Open source license information is in the zlib.ads file.  --
+----------------------------------------------------------------
+
+--  $Id: zlib.adb,v 1.31 2004/09/06 06:53:19 vagul Exp $
+
+with Ada.Exceptions;
+with Ada.Unchecked_Conversion;
+with Ada.Unchecked_Deallocation;
+
+with Interfaces.C.Strings;
+
+with ZLib.Thin;
+
+package body ZLib is
+
+   use type Thin.Int;
+
+   type Z_Stream is new Thin.Z_Stream;
+
+   type Return_Code_Enum is
+      (OK,
+       STREAM_END,
+       NEED_DICT,
+       ERRNO,
+       STREAM_ERROR,
+       DATA_ERROR,
+       MEM_ERROR,
+       BUF_ERROR,
+       VERSION_ERROR);
+
+   type Flate_Step_Function is access
+     function (Strm : in Thin.Z_Streamp; Flush : in Thin.Int) return Thin.Int;
+   pragma Convention (C, Flate_Step_Function);
+
+   type Flate_End_Function is access
+      function (Ctrm : in Thin.Z_Streamp) return Thin.Int;
+   pragma Convention (C, Flate_End_Function);
+
+   type Flate_Type is record
+      Step : Flate_Step_Function;
+      Done : Flate_End_Function;
+   end record;
+
+   subtype Footer_Array is Stream_Element_Array (1 .. 8);
+
+   Simple_GZip_Header : constant Stream_Element_Array (1 .. 10)
+     := (16#1f#, 16#8b#,                 --  Magic header
+         16#08#,                         --  Z_DEFLATED
+         16#00#,                         --  Flags
+         16#00#, 16#00#, 16#00#, 16#00#, --  Time
+         16#00#,                         --  XFlags
+         16#03#                          --  OS code
+        );
+   --  The simplest gzip header is not for informational, but just for
+   --  gzip format compatibility.
+   --  Note that some code below is using assumption
+   --  Simple_GZip_Header'Last > Footer_Array'Last, so do not make
+   --  Simple_GZip_Header'Last <= Footer_Array'Last.
+
+   Return_Code : constant array (Thin.Int range <>) of Return_Code_Enum
+     := (0 => OK,
+         1 => STREAM_END,
+         2 => NEED_DICT,
+        -1 => ERRNO,
+        -2 => STREAM_ERROR,
+        -3 => DATA_ERROR,
+        -4 => MEM_ERROR,
+        -5 => BUF_ERROR,
+        -6 => VERSION_ERROR);
+
+   Flate : constant array (Boolean) of Flate_Type
+     := (True  => (Step => Thin.Deflate'Access,
+                   Done => Thin.DeflateEnd'Access),
+         False => (Step => Thin.Inflate'Access,
+                   Done => Thin.InflateEnd'Access));
+
+   Flush_Finish : constant array (Boolean) of Flush_Mode
+     := (True => Finish, False => No_Flush);
+
+   procedure Raise_Error (Stream : in Z_Stream);
+   pragma Inline (Raise_Error);
+
+   procedure Raise_Error (Message : in String);
+   pragma Inline (Raise_Error);
+
+   procedure Check_Error (Stream : in Z_Stream; Code : in Thin.Int);
+
+   procedure Free is new Ada.Unchecked_Deallocation
+      (Z_Stream, Z_Stream_Access);
+
+   function To_Thin_Access is new Ada.Unchecked_Conversion
+     (Z_Stream_Access, Thin.Z_Streamp);
+
+   procedure Translate_GZip
+     (Filter    : in out Filter_Type;
+      In_Data   : in     Ada.Streams.Stream_Element_Array;
+      In_Last   :    out Ada.Streams.Stream_Element_Offset;
+      Out_Data  :    out Ada.Streams.Stream_Element_Array;
+      Out_Last  :    out Ada.Streams.Stream_Element_Offset;
+      Flush     : in     Flush_Mode);
+   --  Separate translate routine for make gzip header.
+
+   procedure Translate_Auto
+     (Filter    : in out Filter_Type;
+      In_Data   : in     Ada.Streams.Stream_Element_Array;
+      In_Last   :    out Ada.Streams.Stream_Element_Offset;
+      Out_Data  :    out Ada.Streams.Stream_Element_Array;
+      Out_Last  :    out Ada.Streams.Stream_Element_Offset;
+      Flush     : in     Flush_Mode);
+   --  translate routine without additional headers.
+
+   -----------------
+   -- Check_Error --
+   -----------------
+
+   procedure Check_Error (Stream : in Z_Stream; Code : in Thin.Int) is
+      use type Thin.Int;
+   begin
+      if Code /= Thin.Z_OK then
+         Raise_Error
+            (Return_Code_Enum'Image (Return_Code (Code))
+              & ": " & Last_Error_Message (Stream));
+      end if;
+   end Check_Error;
+
+   -----------
+   -- Close --
+   -----------
+
+   procedure Close
+     (Filter       : in out Filter_Type;
+      Ignore_Error : in     Boolean := False)
+   is
+      Code : Thin.Int;
+   begin
+      if not Ignore_Error and then not Is_Open (Filter) then
+         raise Status_Error;
+      end if;
+
+      Code := Flate (Filter.Compression).Done (To_Thin_Access (Filter.Strm));
+
+      if Ignore_Error or else Code = Thin.Z_OK then
+         Free (Filter.Strm);
+      else
+         declare
+            Error_Message : constant String
+              := Last_Error_Message (Filter.Strm.all);
+         begin
+            Free (Filter.Strm);
+            Ada.Exceptions.Raise_Exception
+               (ZLib_Error'Identity,
+                Return_Code_Enum'Image (Return_Code (Code))
+                  & ": " & Error_Message);
+         end;
+      end if;
+   end Close;
+
+   -----------
+   -- CRC32 --
+   -----------
+
+   function CRC32
+     (CRC  : in Unsigned_32;
+      Data : in Ada.Streams.Stream_Element_Array)
+      return Unsigned_32
+   is
+      use Thin;
+   begin
+      return Unsigned_32 (crc32 (ULong (CRC),
+                                 Data'Address,
+                                 Data'Length));
+   end CRC32;
+
+   procedure CRC32
+     (CRC  : in out Unsigned_32;
+      Data : in     Ada.Streams.Stream_Element_Array) is
+   begin
+      CRC := CRC32 (CRC, Data);
+   end CRC32;
+
+   ------------------
+   -- Deflate_Init --
+   ------------------
+
+   procedure Deflate_Init
+     (Filter       : in out Filter_Type;
+      Level        : in     Compression_Level  := Default_Compression;
+      Strategy     : in     Strategy_Type      := Default_Strategy;
+      Method       : in     Compression_Method := Deflated;
+      Window_Bits  : in     Window_Bits_Type   := Default_Window_Bits;
+      Memory_Level : in     Memory_Level_Type  := Default_Memory_Level;
+      Header       : in     Header_Type        := Default)
+   is
+      use type Thin.Int;
+      Win_Bits : Thin.Int := Thin.Int (Window_Bits);
+   begin
+      if Is_Open (Filter) then
+         raise Status_Error;
+      end if;
+
+      --  We allow ZLib to make header only in case of default header type.
+      --  Otherwise we would either do header by ourselfs, or do not do
+      --  header at all.
+
+      if Header = None or else Header = GZip then
+         Win_Bits := -Win_Bits;
+      end if;
+
+      --  For the GZip CRC calculation and make headers.
+
+      if Header = GZip then
+         Filter.CRC    := 0;
+         Filter.Offset := Simple_GZip_Header'First;
+      else
+         Filter.Offset := Simple_GZip_Header'Last + 1;
+      end if;
+
+      Filter.Strm        := new Z_Stream;
+      Filter.Compression := True;
+      Filter.Stream_End  := False;
+      Filter.Header      := Header;
+
+      if Thin.Deflate_Init
+           (To_Thin_Access (Filter.Strm),
+            Level      => Thin.Int (Level),
+            method     => Thin.Int (Method),
+            windowBits => Win_Bits,
+            memLevel   => Thin.Int (Memory_Level),
+            strategy   => Thin.Int (Strategy)) /= Thin.Z_OK
+      then
+         Raise_Error (Filter.Strm.all);
+      end if;
+   end Deflate_Init;
+
+   -----------
+   -- Flush --
+   -----------
+
+   procedure Flush
+     (Filter    : in out Filter_Type;
+      Out_Data  :    out Ada.Streams.Stream_Element_Array;
+      Out_Last  :    out Ada.Streams.Stream_Element_Offset;
+      Flush     : in     Flush_Mode)
+   is
+      No_Data : Stream_Element_Array := (1 .. 0 => 0);
+      Last    : Stream_Element_Offset;
+   begin
+      Translate (Filter, No_Data, Last, Out_Data, Out_Last, Flush);
+   end Flush;
+
+   -----------------------
+   -- Generic_Translate --
+   -----------------------
+
+   procedure Generic_Translate
+     (Filter          : in out ZLib.Filter_Type;
+      In_Buffer_Size  : in     Integer := Default_Buffer_Size;
+      Out_Buffer_Size : in     Integer := Default_Buffer_Size)
+   is
+      In_Buffer  : Stream_Element_Array
+                     (1 .. Stream_Element_Offset (In_Buffer_Size));
+      Out_Buffer : Stream_Element_Array
+                     (1 .. Stream_Element_Offset (Out_Buffer_Size));
+      Last       : Stream_Element_Offset;
+      In_Last    : Stream_Element_Offset;
+      In_First   : Stream_Element_Offset;
+      Out_Last   : Stream_Element_Offset;
+   begin
+      Main : loop
+         Data_In (In_Buffer, Last);
+
+         In_First := In_Buffer'First;
+
+         loop
+            Translate
+              (Filter   => Filter,
+               In_Data  => In_Buffer (In_First .. Last),
+               In_Last  => In_Last,
+               Out_Data => Out_Buffer,
+               Out_Last => Out_Last,
+               Flush    => Flush_Finish (Last < In_Buffer'First));
+
+            if Out_Buffer'First <= Out_Last then
+               Data_Out (Out_Buffer (Out_Buffer'First .. Out_Last));
+            end if;
+
+            exit Main when Stream_End (Filter);
+
+            --  The end of in buffer.
+
+            exit when In_Last = Last;
+
+            In_First := In_Last + 1;
+         end loop;
+      end loop Main;
+
+   end Generic_Translate;
+
+   ------------------
+   -- Inflate_Init --
+   ------------------
+
+   procedure Inflate_Init
+     (Filter      : in out Filter_Type;
+      Window_Bits : in     Window_Bits_Type := Default_Window_Bits;
+      Header      : in     Header_Type      := Default)
+   is
+      use type Thin.Int;
+      Win_Bits : Thin.Int := Thin.Int (Window_Bits);
+
+      procedure Check_Version;
+      --  Check the latest header types compatibility.
+
+      procedure Check_Version is
+      begin
+         if Version <= "1.1.4" then
+            Raise_Error
+              ("Inflate header type " & Header_Type'Image (Header)
+               & " incompatible with ZLib version " & Version);
+         end if;
+      end Check_Version;
+
+   begin
+      if Is_Open (Filter) then
+         raise Status_Error;
+      end if;
+
+      case Header is
+         when None =>
+            Check_Version;
+
+            --  Inflate data without headers determined
+            --  by negative Win_Bits.
+
+            Win_Bits := -Win_Bits;
+         when GZip =>
+            Check_Version;
+
+            --  Inflate gzip data defined by flag 16.
+
+            Win_Bits := Win_Bits + 16;
+         when Auto =>
+            Check_Version;
+
+            --  Inflate with automatic detection
+            --  of gzip or native header defined by flag 32.
+
+            Win_Bits := Win_Bits + 32;
+         when Default => null;
+      end case;
+
+      Filter.Strm        := new Z_Stream;
+      Filter.Compression := False;
+      Filter.Stream_End  := False;
+      Filter.Header      := Header;
+
+      if Thin.Inflate_Init
+         (To_Thin_Access (Filter.Strm), Win_Bits) /= Thin.Z_OK
+      then
+         Raise_Error (Filter.Strm.all);
+      end if;
+   end Inflate_Init;
+
+   -------------
+   -- Is_Open --
+   -------------
+
+   function Is_Open (Filter : in Filter_Type) return Boolean is
+   begin
+      return Filter.Strm /= null;
+   end Is_Open;
+
+   -----------------
+   -- Raise_Error --
+   -----------------
+
+   procedure Raise_Error (Message : in String) is
+   begin
+      Ada.Exceptions.Raise_Exception (ZLib_Error'Identity, Message);
+   end Raise_Error;
+
+   procedure Raise_Error (Stream : in Z_Stream) is
+   begin
+      Raise_Error (Last_Error_Message (Stream));
+   end Raise_Error;
+
+   ----------
+   -- Read --
+   ----------
+
+   procedure Read
+     (Filter : in out Filter_Type;
+      Item   :    out Ada.Streams.Stream_Element_Array;
+      Last   :    out Ada.Streams.Stream_Element_Offset;
+      Flush  : in     Flush_Mode := No_Flush)
+   is
+      In_Last    : Stream_Element_Offset;
+      Item_First : Ada.Streams.Stream_Element_Offset := Item'First;
+      V_Flush    : Flush_Mode := Flush;
+
+   begin
+      pragma Assert (Rest_First in Buffer'First .. Buffer'Last + 1);
+      pragma Assert (Rest_Last in Buffer'First - 1 .. Buffer'Last);
+
+      loop
+         if Rest_Last = Buffer'First - 1 then
+            V_Flush := Finish;
+
+         elsif Rest_First > Rest_Last then
+            Read (Buffer, Rest_Last);
+            Rest_First := Buffer'First;
+
+            if Rest_Last < Buffer'First then
+               V_Flush := Finish;
+            end if;
+         end if;
+
+         Translate
+           (Filter   => Filter,
+            In_Data  => Buffer (Rest_First .. Rest_Last),
+            In_Last  => In_Last,
+            Out_Data => Item (Item_First .. Item'Last),
+            Out_Last => Last,
+            Flush    => V_Flush);
+
+         Rest_First := In_Last + 1;
+
+         exit when Stream_End (Filter)
+           or else Last = Item'Last
+           or else (Last >= Item'First and then Allow_Read_Some);
+
+         Item_First := Last + 1;
+      end loop;
+   end Read;
+
+   ----------------
+   -- Stream_End --
+   ----------------
+
+   function Stream_End (Filter : in Filter_Type) return Boolean is
+   begin
+      if Filter.Header = GZip and Filter.Compression then
+         return Filter.Stream_End
+            and then Filter.Offset = Footer_Array'Last + 1;
+      else
+         return Filter.Stream_End;
+      end if;
+   end Stream_End;
+
+   --------------
+   -- Total_In --
+   --------------
+
+   function Total_In (Filter : in Filter_Type) return Count is
+   begin
+      return Count (Thin.Total_In (To_Thin_Access (Filter.Strm).all));
+   end Total_In;
+
+   ---------------
+   -- Total_Out --
+   ---------------
+
+   function Total_Out (Filter : in Filter_Type) return Count is
+   begin
+      return Count (Thin.Total_Out (To_Thin_Access (Filter.Strm).all));
+   end Total_Out;
+
+   ---------------
+   -- Translate --
+   ---------------
+
+   procedure Translate
+     (Filter    : in out Filter_Type;
+      In_Data   : in     Ada.Streams.Stream_Element_Array;
+      In_Last   :    out Ada.Streams.Stream_Element_Offset;
+      Out_Data  :    out Ada.Streams.Stream_Element_Array;
+      Out_Last  :    out Ada.Streams.Stream_Element_Offset;
+      Flush     : in     Flush_Mode) is
+   begin
+      if Filter.Header = GZip and then Filter.Compression then
+         Translate_GZip
+           (Filter   => Filter,
+            In_Data  => In_Data,
+            In_Last  => In_Last,
+            Out_Data => Out_Data,
+            Out_Last => Out_Last,
+            Flush    => Flush);
+      else
+         Translate_Auto
+           (Filter   => Filter,
+            In_Data  => In_Data,
+            In_Last  => In_Last,
+            Out_Data => Out_Data,
+            Out_Last => Out_Last,
+            Flush    => Flush);
+      end if;
+   end Translate;
+
+   --------------------
+   -- Translate_Auto --
+   --------------------
+
+   procedure Translate_Auto
+     (Filter    : in out Filter_Type;
+      In_Data   : in     Ada.Streams.Stream_Element_Array;
+      In_Last   :    out Ada.Streams.Stream_Element_Offset;
+      Out_Data  :    out Ada.Streams.Stream_Element_Array;
+      Out_Last  :    out Ada.Streams.Stream_Element_Offset;
+      Flush     : in     Flush_Mode)
+   is
+      use type Thin.Int;
+      Code : Thin.Int;
+
+   begin
+      if not Is_Open (Filter) then
+         raise Status_Error;
+      end if;
+
+      if Out_Data'Length = 0 and then In_Data'Length = 0 then
+         raise Constraint_Error;
+      end if;
+
+      Set_Out (Filter.Strm.all, Out_Data'Address, Out_Data'Length);
+      Set_In  (Filter.Strm.all, In_Data'Address, In_Data'Length);
+
+      Code := Flate (Filter.Compression).Step
+        (To_Thin_Access (Filter.Strm),
+         Thin.Int (Flush));
+
+      if Code = Thin.Z_STREAM_END then
+         Filter.Stream_End := True;
+      else
+         Check_Error (Filter.Strm.all, Code);
+      end if;
+
+      In_Last  := In_Data'Last
+         - Stream_Element_Offset (Avail_In (Filter.Strm.all));
+      Out_Last := Out_Data'Last
+         - Stream_Element_Offset (Avail_Out (Filter.Strm.all));
+   end Translate_Auto;
+
+   --------------------
+   -- Translate_GZip --
+   --------------------
+
+   procedure Translate_GZip
+     (Filter    : in out Filter_Type;
+      In_Data   : in     Ada.Streams.Stream_Element_Array;
+      In_Last   :    out Ada.Streams.Stream_Element_Offset;
+      Out_Data  :    out Ada.Streams.Stream_Element_Array;
+      Out_Last  :    out Ada.Streams.Stream_Element_Offset;
+      Flush     : in     Flush_Mode)
+   is
+      Out_First : Stream_Element_Offset;
+
+      procedure Add_Data (Data : in Stream_Element_Array);
+      --  Add data to stream from the Filter.Offset till necessary,
+      --  used for add gzip headr/footer.
+
+      procedure Put_32
+        (Item : in out Stream_Element_Array;
+         Data : in     Unsigned_32);
+      pragma Inline (Put_32);
+
+      --------------
+      -- Add_Data --
+      --------------
+
+      procedure Add_Data (Data : in Stream_Element_Array) is
+         Data_First : Stream_Element_Offset renames Filter.Offset;
+         Data_Last  : Stream_Element_Offset;
+         Data_Len   : Stream_Element_Offset; --  -1
+         Out_Len    : Stream_Element_Offset; --  -1
+      begin
+         Out_First := Out_Last + 1;
+
+         if Data_First > Data'Last then
+            return;
+         end if;
+
+         Data_Len  := Data'Last     - Data_First;
+         Out_Len   := Out_Data'Last - Out_First;
+
+         if Data_Len <= Out_Len then
+            Out_Last  := Out_First  + Data_Len;
+            Data_Last := Data'Last;
+         else
+            Out_Last  := Out_Data'Last;
+            Data_Last := Data_First + Out_Len;
+         end if;
+
+         Out_Data (Out_First .. Out_Last) := Data (Data_First .. Data_Last);
+
+         Data_First := Data_Last + 1;
+         Out_First  := Out_Last + 1;
+      end Add_Data;
+
+      ------------
+      -- Put_32 --
+      ------------
+
+      procedure Put_32
+        (Item : in out Stream_Element_Array;
+         Data : in     Unsigned_32)
+      is
+         D : Unsigned_32 := Data;
+      begin
+         for J in Item'First .. Item'First + 3 loop
+            Item (J) := Stream_Element (D and 16#FF#);
+            D := Shift_Right (D, 8);
+         end loop;
+      end Put_32;
+
+   begin
+      Out_Last := Out_Data'First - 1;
+
+      if not Filter.Stream_End then
+         Add_Data (Simple_GZip_Header);
+
+         Translate_Auto
+           (Filter   => Filter,
+            In_Data  => In_Data,
+            In_Last  => In_Last,
+            Out_Data => Out_Data (Out_First .. Out_Data'Last),
+            Out_Last => Out_Last,
+            Flush    => Flush);
+
+         CRC32 (Filter.CRC, In_Data (In_Data'First .. In_Last));
+      end if;
+
+      if Filter.Stream_End and then Out_Last <= Out_Data'Last then
+         --  This detection method would work only when
+         --  Simple_GZip_Header'Last > Footer_Array'Last
+
+         if Filter.Offset = Simple_GZip_Header'Last + 1 then
+            Filter.Offset := Footer_Array'First;
+         end if;
+
+         declare
+            Footer : Footer_Array;
+         begin
+            Put_32 (Footer, Filter.CRC);
+            Put_32 (Footer (Footer'First + 4 .. Footer'Last),
+                    Unsigned_32 (Total_In (Filter)));
+            Add_Data (Footer);
+         end;
+      end if;
+   end Translate_GZip;
+
+   -------------
+   -- Version --
+   -------------
+
+   function Version return String is
+   begin
+      return Interfaces.C.Strings.Value (Thin.zlibVersion);
+   end Version;
+
+   -----------
+   -- Write --
+   -----------
+
+   procedure Write
+     (Filter : in out Filter_Type;
+      Item   : in     Ada.Streams.Stream_Element_Array;
+      Flush  : in     Flush_Mode := No_Flush)
+   is
+      Buffer   : Stream_Element_Array (1 .. Buffer_Size);
+      In_Last  : Stream_Element_Offset;
+      Out_Last : Stream_Element_Offset;
+      In_First : Stream_Element_Offset := Item'First;
+   begin
+      if Item'Length = 0 and Flush = No_Flush then
+         return;
+      end if;
+
+      loop
+         Translate
+           (Filter   => Filter,
+            In_Data  => Item (In_First .. Item'Last),
+            In_Last  => In_Last,
+            Out_Data => Buffer,
+            Out_Last => Out_Last,
+            Flush    => Flush);
+
+         if Out_Last >= Buffer'First then
+            Write (Buffer (1 .. Out_Last));
+         end if;
+
+         exit when In_Last = Item'Last or Stream_End (Filter);
+
+         In_First := In_Last + 1;
+      end loop;
+   end Write;
+
+end ZLib;
diff --git a/gs/zlib/contrib/ada/zlib.ads b/gs/zlib/contrib/ada/zlib.ads
new file mode 100644
index 000000000..79ffc4095
--- /dev/null
+++ b/gs/zlib/contrib/ada/zlib.ads
@@ -0,0 +1,328 @@
+------------------------------------------------------------------------------
+--                      ZLib for Ada thick binding.                         --
+--                                                                          --
+--              Copyright (C) 2002-2004 Dmitriy Anisimkov                   --
+--                                                                          --
+--  This library is free software; you can redistribute it and/or modify    --
+--  it under the terms of the GNU General Public License as published by    --
+--  the Free Software Foundation; either version 2 of the License, or (at   --
+--  your option) any later version.                                         --
+--                                                                          --
+--  This library is distributed in the hope that it will be useful, but     --
+--  WITHOUT ANY WARRANTY; without even the implied warranty of              --
+--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU       --
+--  General Public License for more details.                                --
+--                                                                          --
+--  You should have received a copy of the GNU General Public License       --
+--  along with this library; if not, write to the Free Software Foundation, --
+--  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.          --
+--                                                                          --
+--  As a special exception, if other files instantiate generics from this   --
+--  unit, or you link this unit with other files to produce an executable,  --
+--  this  unit  does not  by itself cause  the resulting executable to be   --
+--  covered by the GNU General Public License. This exception does not      --
+--  however invalidate any other reasons why the executable file  might be  --
+--  covered by the  GNU Public License.                                     --
+------------------------------------------------------------------------------
+
+--  $Id: zlib.ads,v 1.26 2004/09/06 06:53:19 vagul Exp $
+
+with Ada.Streams;
+
+with Interfaces;
+
+package ZLib is
+
+   ZLib_Error   : exception;
+   Status_Error : exception;
+
+   type Compression_Level is new Integer range -1 .. 9;
+
+   type Flush_Mode is private;
+
+   type Compression_Method is private;
+
+   type Window_Bits_Type is new Integer range 8 .. 15;
+
+   type Memory_Level_Type is new Integer range 1 .. 9;
+
+   type Unsigned_32 is new Interfaces.Unsigned_32;
+
+   type Strategy_Type is private;
+
+   type Header_Type is (None, Auto, Default, GZip);
+   --  Header type usage have a some limitation for inflate.
+   --  See comment for Inflate_Init.
+
+   subtype Count is Ada.Streams.Stream_Element_Count;
+
+   Default_Memory_Level : constant Memory_Level_Type := 8;
+   Default_Window_Bits  : constant Window_Bits_Type  := 15;
+
+   ----------------------------------
+   -- Compression method constants --
+   ----------------------------------
+
+   Deflated : constant Compression_Method;
+   --  Only one method allowed in this ZLib version
+
+   ---------------------------------
+   -- Compression level constants --
+   ---------------------------------
+
+   No_Compression      : constant Compression_Level := 0;
+   Best_Speed          : constant Compression_Level := 1;
+   Best_Compression    : constant Compression_Level := 9;
+   Default_Compression : constant Compression_Level := -1;
+
+   --------------------------
+   -- Flush mode constants --
+   --------------------------
+
+   No_Flush      : constant Flush_Mode;
+   --  Regular way for compression, no flush
+
+   Partial_Flush : constant Flush_Mode;
+   --  Will be removed, use Z_SYNC_FLUSH instead
+
+   Sync_Flush    : constant Flush_Mode;
+   --  All pending output is flushed to the output buffer and the output
+   --  is aligned on a byte boundary, so that the decompressor can get all
+   --  input data available so far. (In particular avail_in is zero after the
+   --  call if enough output space has been provided  before the call.)
+   --  Flushing may degrade compression for some compression algorithms and so
+   --  it should be used only when necessary.
+
+   Block_Flush   : constant Flush_Mode;
+   --  Z_BLOCK requests that inflate() stop
+   --  if and when it get to the next deflate block boundary. When decoding the
+   --  zlib or gzip format, this will cause inflate() to return immediately
+   --  after the header and before the first block. When doing a raw inflate,
+   --  inflate() will go ahead and process the first block, and will return
+   --  when it gets to the end of that block, or when it runs out of data.
+
+   Full_Flush    : constant Flush_Mode;
+   --  All output is flushed as with SYNC_FLUSH, and the compression state
+   --  is reset so that decompression can restart from this point if previous
+   --  compressed data has been damaged or if random access is desired. Using
+   --  Full_Flush too often can seriously degrade the compression.
+
+   Finish        : constant Flush_Mode;
+   --  Just for tell the compressor that input data is complete.
+
+   ------------------------------------
+   -- Compression strategy constants --
+   ------------------------------------
+
+   --  RLE stategy could be used only in version 1.2.0 and later.
+
+   Filtered         : constant Strategy_Type;
+   Huffman_Only     : constant Strategy_Type;
+   RLE              : constant Strategy_Type;
+   Default_Strategy : constant Strategy_Type;
+
+   Default_Buffer_Size : constant := 4096;
+
+   type Filter_Type is tagged limited private;
+   --  The filter is for compression and for decompression.
+   --  The usage of the type is depend of its initialization.
+
+   function Version return String;
+   pragma Inline (Version);
+   --  Return string representation of the ZLib version.
+
+   procedure Deflate_Init
+     (Filter       : in out Filter_Type;
+      Level        : in     Compression_Level  := Default_Compression;
+      Strategy     : in     Strategy_Type      := Default_Strategy;
+      Method       : in     Compression_Method := Deflated;
+      Window_Bits  : in     Window_Bits_Type   := Default_Window_Bits;
+      Memory_Level : in     Memory_Level_Type  := Default_Memory_Level;
+      Header       : in     Header_Type        := Default);
+   --  Compressor initialization.
+   --  When Header parameter is Auto or Default, then default zlib header
+   --  would be provided for compressed data.
+   --  When Header is GZip, then gzip header would be set instead of
+   --  default header.
+   --  When Header is None, no header would be set for compressed data.
+
+   procedure Inflate_Init
+     (Filter      : in out Filter_Type;
+      Window_Bits : in     Window_Bits_Type := Default_Window_Bits;
+      Header      : in     Header_Type      := Default);
+   --  Decompressor initialization.
+   --  Default header type mean that ZLib default header is expecting in the
+   --  input compressed stream.
+   --  Header type None mean that no header is expecting in the input stream.
+   --  GZip header type mean that GZip header is expecting in the
+   --  input compressed stream.
+   --  Auto header type mean that header type (GZip or Native) would be
+   --  detected automatically in the input stream.
+   --  Note that header types parameter values None, GZip and Auto are
+   --  supported for inflate routine only in ZLib versions 1.2.0.2 and later.
+   --  Deflate_Init is supporting all header types.
+
+   function Is_Open (Filter : in Filter_Type) return Boolean;
+   pragma Inline (Is_Open);
+   --  Is the filter opened for compression or decompression.
+
+   procedure Close
+     (Filter       : in out Filter_Type;
+      Ignore_Error : in     Boolean := False);
+   --  Closing the compression or decompressor.
+   --  If stream is closing before the complete and Ignore_Error is False,
+   --  The exception would be raised.
+
+   generic
+      with procedure Data_In
+        (Item : out Ada.Streams.Stream_Element_Array;
+         Last : out Ada.Streams.Stream_Element_Offset);
+      with procedure Data_Out
+        (Item : in Ada.Streams.Stream_Element_Array);
+   procedure Generic_Translate
+     (Filter          : in out Filter_Type;
+      In_Buffer_Size  : in     Integer := Default_Buffer_Size;
+      Out_Buffer_Size : in     Integer := Default_Buffer_Size);
+   --  Compress/decompress data fetch from Data_In routine and pass the result
+   --  to the Data_Out routine. User should provide Data_In and Data_Out
+   --  for compression/decompression data flow.
+   --  Compression or decompression depend on Filter initialization.
+
+   function Total_In (Filter : in Filter_Type) return Count;
+   pragma Inline (Total_In);
+   --  Returns total number of input bytes read so far
+
+   function Total_Out (Filter : in Filter_Type) return Count;
+   pragma Inline (Total_Out);
+   --  Returns total number of bytes output so far
+
+   function CRC32
+     (CRC    : in Unsigned_32;
+      Data   : in Ada.Streams.Stream_Element_Array)
+      return Unsigned_32;
+   pragma Inline (CRC32);
+   --  Compute CRC32, it could be necessary for make gzip format
+
+   procedure CRC32
+     (CRC  : in out Unsigned_32;
+      Data : in     Ada.Streams.Stream_Element_Array);
+   pragma Inline (CRC32);
+   --  Compute CRC32, it could be necessary for make gzip format
+
+   -------------------------------------------------
+   --  Below is more complex low level routines.  --
+   -------------------------------------------------
+
+   procedure Translate
+     (Filter    : in out Filter_Type;
+      In_Data   : in     Ada.Streams.Stream_Element_Array;
+      In_Last   :    out Ada.Streams.Stream_Element_Offset;
+      Out_Data  :    out Ada.Streams.Stream_Element_Array;
+      Out_Last  :    out Ada.Streams.Stream_Element_Offset;
+      Flush     : in     Flush_Mode);
+   --  Compress/decompress the In_Data buffer and place the result into
+   --  Out_Data. In_Last is the index of last element from In_Data accepted by
+   --  the Filter. Out_Last is the last element of the received data from
+   --  Filter. To tell the filter that incoming data are complete put the
+   --  Flush parameter to Finish.
+
+   function Stream_End (Filter : in Filter_Type) return Boolean;
+   pragma Inline (Stream_End);
+   --  Return the true when the stream is complete.
+
+   procedure Flush
+     (Filter    : in out Filter_Type;
+      Out_Data  :    out Ada.Streams.Stream_Element_Array;
+      Out_Last  :    out Ada.Streams.Stream_Element_Offset;
+      Flush     : in     Flush_Mode);
+   pragma Inline (Flush);
+   --  Flushing the data from the compressor.
+
+   generic
+      with procedure Write
+        (Item : in Ada.Streams.Stream_Element_Array);
+      --  User should provide this routine for accept
+      --  compressed/decompressed data.
+
+      Buffer_Size : in Ada.Streams.Stream_Element_Offset
+         := Default_Buffer_Size;
+      --  Buffer size for Write user routine.
+
+   procedure Write
+     (Filter  : in out Filter_Type;
+      Item    : in     Ada.Streams.Stream_Element_Array;
+      Flush   : in     Flush_Mode := No_Flush);
+   --  Compress/Decompress data from Item to the generic parameter procedure
+   --  Write. Output buffer size could be set in Buffer_Size generic parameter.
+
+   generic
+      with procedure Read
+        (Item : out Ada.Streams.Stream_Element_Array;
+         Last : out Ada.Streams.Stream_Element_Offset);
+      --  User should provide data for compression/decompression
+      --  thru this routine.
+
+      Buffer : in out Ada.Streams.Stream_Element_Array;
+      --  Buffer for keep remaining data from the previous
+      --  back read.
+
+      Rest_First, Rest_Last : in out Ada.Streams.Stream_Element_Offset;
+      --  Rest_First have to be initialized to Buffer'Last + 1
+      --  Rest_Last have to be initialized to Buffer'Last
+      --  before usage.
+
+      Allow_Read_Some : in Boolean := False;
+      --  Is it allowed to return Last < Item'Last before end of data.
+
+   procedure Read
+     (Filter : in out Filter_Type;
+      Item   :    out Ada.Streams.Stream_Element_Array;
+      Last   :    out Ada.Streams.Stream_Element_Offset;
+      Flush  : in     Flush_Mode := No_Flush);
+   --  Compress/Decompress data from generic parameter procedure Read to the
+   --  Item. User should provide Buffer and initialized Rest_First, Rest_Last
+   --  indicators. If Allow_Read_Some is True, Read routines could return
+   --  Last < Item'Last only at end of stream.
+
+private
+
+   use Ada.Streams;
+
+   pragma Assert (Ada.Streams.Stream_Element'Size    =    8);
+   pragma Assert (Ada.Streams.Stream_Element'Modulus = 2**8);
+
+   type Flush_Mode is new Integer range 0 .. 5;
+
+   type Compression_Method is new Integer range 8 .. 8;
+
+   type Strategy_Type is new Integer range 0 .. 3;
+
+   No_Flush      : constant Flush_Mode := 0;
+   Partial_Flush : constant Flush_Mode := 1;
+   Sync_Flush    : constant Flush_Mode := 2;
+   Full_Flush    : constant Flush_Mode := 3;
+   Finish        : constant Flush_Mode := 4;
+   Block_Flush   : constant Flush_Mode := 5;
+
+   Filtered         : constant Strategy_Type := 1;
+   Huffman_Only     : constant Strategy_Type := 2;
+   RLE              : constant Strategy_Type := 3;
+   Default_Strategy : constant Strategy_Type := 0;
+
+   Deflated : constant Compression_Method := 8;
+
+   type Z_Stream;
+
+   type Z_Stream_Access is access all Z_Stream;
+
+   type Filter_Type is tagged limited record
+      Strm        : Z_Stream_Access;
+      Compression : Boolean;
+      Stream_End  : Boolean;
+      Header      : Header_Type;
+      CRC         : Unsigned_32;
+      Offset      : Stream_Element_Offset;
+      --  Offset for gzip header/footer output.
+   end record;
+
+end ZLib;
diff --git a/gs/zlib/contrib/ada/zlib.gpr b/gs/zlib/contrib/ada/zlib.gpr
new file mode 100644
index 000000000..296b22aa9
--- /dev/null
+++ b/gs/zlib/contrib/ada/zlib.gpr
@@ -0,0 +1,20 @@
+project Zlib is
+
+   for Languages use ("Ada");
+   for Source_Dirs use (".");
+   for Object_Dir use ".";
+   for Main use ("test.adb", "mtest.adb", "read.adb", "buffer_demo");
+
+   package Compiler is
+      for Default_Switches ("ada") use ("-gnatwcfilopru", "-gnatVcdfimorst", "-gnatyabcefhiklmnoprst");
+   end Compiler;
+
+   package Linker is
+      for Default_Switches ("ada") use ("-lz");
+   end Linker;
+
+   package Builder is
+      for Default_Switches ("ada") use ("-s", "-gnatQ");
+   end Builder;
+
+end Zlib;
diff --git a/gs/zlib/contrib/asm586/README.586 b/gs/zlib/contrib/asm586/README.586
new file mode 100644
index 000000000..6bb78f320
--- /dev/null
+++ b/gs/zlib/contrib/asm586/README.586
@@ -0,0 +1,43 @@
+This is a patched version of zlib modified to use
+Pentium-optimized assembly code in the deflation algorithm. The files
+changed/added by this patch are:
+
+README.586
+match.S
+
+The effectiveness of these modifications is a bit marginal, as the the
+program's bottleneck seems to be mostly L1-cache contention, for which
+there is no real way to work around without rewriting the basic
+algorithm. The speedup on average is around 5-10% (which is generally
+less than the amount of variance between subsequent executions).
+However, when used at level 9 compression, the cache contention can
+drop enough for the assembly version to achieve 10-20% speedup (and
+sometimes more, depending on the amount of overall redundancy in the
+files). Even here, though, cache contention can still be the limiting
+factor, depending on the nature of the program using the zlib library.
+This may also mean that better improvements will be seen on a Pentium
+with MMX, which suffers much less from L1-cache contention, but I have
+not yet verified this.
+
+Note that this code has been tailored for the Pentium in particular,
+and will not perform well on the Pentium Pro (due to the use of a
+partial register in the inner loop).
+
+If you are using an assembler other than GNU as, you will have to
+translate match.S to use your assembler's syntax. (Have fun.)
+
+Brian Raiter
+breadbox@muppetlabs.com
+April, 1998
+
+
+Added for zlib 1.1.3:
+
+The patches come from
+http://www.muppetlabs.com/~breadbox/software/assembly.html
+
+To compile zlib with this asm file, copy match.S to the zlib directory
+then do:
+
+CFLAGS="-O3 -DASMV" ./configure
+make OBJA=match.o
diff --git a/gs/zlib/contrib/asm586/match.S b/gs/zlib/contrib/asm586/match.S
new file mode 100644
index 000000000..0368b35fe
--- /dev/null
+++ b/gs/zlib/contrib/asm586/match.S
@@ -0,0 +1,364 @@
+/* match.s -- Pentium-optimized version of longest_match()
+ * Written for zlib 1.1.2
+ * Copyright (C) 1998 Brian Raiter <breadbox@muppetlabs.com>
+ *
+ * This is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License.
+ */
+
+#ifndef NO_UNDERLINE
+#define	match_init	_match_init
+#define	longest_match	_longest_match
+#endif
+
+#define	MAX_MATCH	(258)
+#define	MIN_MATCH	(3)
+#define	MIN_LOOKAHEAD	(MAX_MATCH + MIN_MATCH + 1)
+#define	MAX_MATCH_8	((MAX_MATCH + 7) & ~7)
+
+/* stack frame offsets */
+
+#define	wmask			0	/* local copy of s->wmask	*/
+#define	window			4	/* local copy of s->window	*/
+#define	windowbestlen		8	/* s->window + bestlen		*/
+#define	chainlenscanend		12	/* high word: current chain len	*/
+					/* low word: last bytes sought	*/
+#define	scanstart		16	/* first two bytes of string	*/
+#define	scanalign		20	/* dword-misalignment of string	*/
+#define	nicematch		24	/* a good enough match size	*/
+#define	bestlen			28	/* size of best match so far	*/
+#define	scan			32	/* ptr to string wanting match	*/
+
+#define	LocalVarsSize		(36)
+/*	saved ebx		36 */
+/*	saved edi		40 */
+/*	saved esi		44 */
+/*	saved ebp		48 */
+/*	return address		52 */
+#define	deflatestate		56	/* the function arguments	*/
+#define	curmatch		60
+
+/* Offsets for fields in the deflate_state structure. These numbers
+ * are calculated from the definition of deflate_state, with the
+ * assumption that the compiler will dword-align the fields. (Thus,
+ * changing the definition of deflate_state could easily cause this
+ * program to crash horribly, without so much as a warning at
+ * compile time. Sigh.)
+ */
+
+/* All the +zlib1222add offsets are due to the addition of fields
+ *  in zlib in the deflate_state structure since the asm code was first written
+ * (if you compile with zlib 1.0.4 or older, use "zlib1222add equ (-4)").
+ * (if you compile with zlib between 1.0.5 and 1.2.2.1, use "zlib1222add equ 0").
+ * if you compile with zlib 1.2.2.2 or later , use "zlib1222add equ 8").
+ */
+
+#define zlib1222add		(8)
+
+#define	dsWSize			(36+zlib1222add)
+#define	dsWMask			(44+zlib1222add)
+#define	dsWindow		(48+zlib1222add)
+#define	dsPrev			(56+zlib1222add)
+#define	dsMatchLen		(88+zlib1222add)
+#define	dsPrevMatch		(92+zlib1222add)
+#define	dsStrStart		(100+zlib1222add)
+#define	dsMatchStart		(104+zlib1222add)
+#define	dsLookahead		(108+zlib1222add)
+#define	dsPrevLen		(112+zlib1222add)
+#define	dsMaxChainLen		(116+zlib1222add)
+#define	dsGoodMatch		(132+zlib1222add)
+#define	dsNiceMatch		(136+zlib1222add)
+
+
+.file "match.S"
+
+.globl	match_init, longest_match
+
+.text
+
+/* uInt longest_match(deflate_state *deflatestate, IPos curmatch) */
+
+longest_match:
+
+/* Save registers that the compiler may be using, and adjust %esp to	*/
+/* make room for our stack frame.					*/
+
+		pushl	%ebp
+		pushl	%edi
+		pushl	%esi
+		pushl	%ebx
+		subl	$LocalVarsSize, %esp
+
+/* Retrieve the function arguments. %ecx will hold cur_match		*/
+/* throughout the entire function. %edx will hold the pointer to the	*/
+/* deflate_state structure during the function's setup (before		*/
+/* entering the main loop).						*/
+
+		movl	deflatestate(%esp), %edx
+		movl	curmatch(%esp), %ecx
+
+/* if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;	*/
+
+		movl	dsNiceMatch(%edx), %eax
+		movl	dsLookahead(%edx), %ebx
+		cmpl	%eax, %ebx
+		jl	LookaheadLess
+		movl	%eax, %ebx
+LookaheadLess:	movl	%ebx, nicematch(%esp)
+
+/* register Bytef *scan = s->window + s->strstart;			*/
+
+		movl	dsWindow(%edx), %esi
+		movl	%esi, window(%esp)
+		movl	dsStrStart(%edx), %ebp
+		lea	(%esi,%ebp), %edi
+		movl	%edi, scan(%esp)
+
+/* Determine how many bytes the scan ptr is off from being		*/
+/* dword-aligned.							*/
+
+		movl	%edi, %eax
+		negl	%eax
+		andl	$3, %eax
+		movl	%eax, scanalign(%esp)
+
+/* IPos limit = s->strstart > (IPos)MAX_DIST(s) ?			*/
+/*     s->strstart - (IPos)MAX_DIST(s) : NIL;				*/
+
+		movl	dsWSize(%edx), %eax
+		subl	$MIN_LOOKAHEAD, %eax
+		subl	%eax, %ebp
+		jg	LimitPositive
+		xorl	%ebp, %ebp
+LimitPositive:
+
+/* unsigned chain_length = s->max_chain_length;				*/
+/* if (s->prev_length >= s->good_match) {				*/
+/*     chain_length >>= 2;						*/
+/* }									*/
+
+		movl	dsPrevLen(%edx), %eax
+		movl	dsGoodMatch(%edx), %ebx
+		cmpl	%ebx, %eax
+		movl	dsMaxChainLen(%edx), %ebx
+		jl	LastMatchGood
+		shrl	$2, %ebx
+LastMatchGood:
+
+/* chainlen is decremented once beforehand so that the function can	*/
+/* use the sign flag instead of the zero flag for the exit test.	*/
+/* It is then shifted into the high word, to make room for the scanend	*/
+/* scanend value, which it will always accompany.			*/
+
+		decl	%ebx
+		shll	$16, %ebx
+
+/* int best_len = s->prev_length;					*/
+
+		movl	dsPrevLen(%edx), %eax
+		movl	%eax, bestlen(%esp)
+
+/* Store the sum of s->window + best_len in %esi locally, and in %esi.	*/
+
+		addl	%eax, %esi
+		movl	%esi, windowbestlen(%esp)
+
+/* register ush scan_start = *(ushf*)scan;				*/
+/* register ush scan_end   = *(ushf*)(scan+best_len-1);			*/
+
+		movw	(%edi), %bx
+		movw	%bx, scanstart(%esp)
+		movw	-1(%edi,%eax), %bx
+		movl	%ebx, chainlenscanend(%esp)
+
+/* Posf *prev = s->prev;						*/
+/* uInt wmask = s->w_mask;						*/
+
+		movl	dsPrev(%edx), %edi
+		movl	dsWMask(%edx), %edx
+		mov	%edx, wmask(%esp)
+
+/* Jump into the main loop.						*/
+
+		jmp	LoopEntry
+
+.balign 16
+
+/* do {
+ *     match = s->window + cur_match;
+ *     if (*(ushf*)(match+best_len-1) != scan_end ||
+ *         *(ushf*)match != scan_start) continue;
+ *     [...]
+ * } while ((cur_match = prev[cur_match & wmask]) > limit
+ *          && --chain_length != 0);
+ *
+ * Here is the inner loop of the function. The function will spend the
+ * majority of its time in this loop, and majority of that time will
+ * be spent in the first ten instructions.
+ *
+ * Within this loop:
+ * %ebx = chainlenscanend - i.e., ((chainlen << 16) | scanend)
+ * %ecx = curmatch
+ * %edx = curmatch & wmask
+ * %esi = windowbestlen - i.e., (window + bestlen)
+ * %edi = prev
+ * %ebp = limit
+ *
+ * Two optimization notes on the choice of instructions:
+ *
+ * The first instruction uses a 16-bit address, which costs an extra,
+ * unpairable cycle. This is cheaper than doing a 32-bit access and
+ * zeroing the high word, due to the 3-cycle misalignment penalty which
+ * would occur half the time. This also turns out to be cheaper than
+ * doing two separate 8-bit accesses, as the memory is so rarely in the
+ * L1 cache.
+ *
+ * The window buffer, however, apparently spends a lot of time in the
+ * cache, and so it is faster to retrieve the word at the end of the
+ * match string with two 8-bit loads. The instructions that test the
+ * word at the beginning of the match string, however, are executed
+ * much less frequently, and there it was cheaper to use 16-bit
+ * instructions, which avoided the necessity of saving off and
+ * subsequently reloading one of the other registers.
+ */
+LookupLoop:
+							/* 1 U & V  */
+		movw	(%edi,%edx,2), %cx		/* 2 U pipe */
+		movl	wmask(%esp), %edx		/* 2 V pipe */
+		cmpl	%ebp, %ecx			/* 3 U pipe */
+		jbe	LeaveNow			/* 3 V pipe */
+		subl	$0x00010000, %ebx		/* 4 U pipe */
+		js	LeaveNow			/* 4 V pipe */
+LoopEntry:	movb	-1(%esi,%ecx), %al		/* 5 U pipe */
+		andl	%ecx, %edx			/* 5 V pipe */
+		cmpb	%bl, %al			/* 6 U pipe */
+		jnz	LookupLoop			/* 6 V pipe */
+		movb	(%esi,%ecx), %ah
+		cmpb	%bh, %ah
+		jnz	LookupLoop
+		movl	window(%esp), %eax
+		movw	(%eax,%ecx), %ax
+		cmpw	scanstart(%esp), %ax
+		jnz	LookupLoop
+
+/* Store the current value of chainlen.					*/
+
+		movl	%ebx, chainlenscanend(%esp)
+
+/* Point %edi to the string under scrutiny, and %esi to the string we	*/
+/* are hoping to match it up with. In actuality, %esi and %edi are	*/
+/* both pointed (MAX_MATCH_8 - scanalign) bytes ahead, and %edx is	*/
+/* initialized to -(MAX_MATCH_8 - scanalign).				*/
+
+		movl	window(%esp), %esi
+		movl	scan(%esp), %edi
+		addl	%ecx, %esi
+		movl	scanalign(%esp), %eax
+		movl	$(-MAX_MATCH_8), %edx
+		lea	MAX_MATCH_8(%edi,%eax), %edi
+		lea	MAX_MATCH_8(%esi,%eax), %esi
+
+/* Test the strings for equality, 8 bytes at a time. At the end,
+ * adjust %edx so that it is offset to the exact byte that mismatched.
+ *
+ * We already know at this point that the first three bytes of the
+ * strings match each other, and they can be safely passed over before
+ * starting the compare loop. So what this code does is skip over 0-3
+ * bytes, as much as necessary in order to dword-align the %edi
+ * pointer. (%esi will still be misaligned three times out of four.)
+ *
+ * It should be confessed that this loop usually does not represent
+ * much of the total running time. Replacing it with a more
+ * straightforward "rep cmpsb" would not drastically degrade
+ * performance.
+ */
+LoopCmps:
+		movl	(%esi,%edx), %eax
+		movl	(%edi,%edx), %ebx
+		xorl	%ebx, %eax
+		jnz	LeaveLoopCmps
+		movl	4(%esi,%edx), %eax
+		movl	4(%edi,%edx), %ebx
+		xorl	%ebx, %eax
+		jnz	LeaveLoopCmps4
+		addl	$8, %edx
+		jnz	LoopCmps
+		jmp	LenMaximum
+LeaveLoopCmps4:	addl	$4, %edx
+LeaveLoopCmps:	testl	$0x0000FFFF, %eax
+		jnz	LenLower
+		addl	$2, %edx
+		shrl	$16, %eax
+LenLower:	subb	$1, %al
+		adcl	$0, %edx
+
+/* Calculate the length of the match. If it is longer than MAX_MATCH,	*/
+/* then automatically accept it as the best possible match and leave.	*/
+
+		lea	(%edi,%edx), %eax
+		movl	scan(%esp), %edi
+		subl	%edi, %eax
+		cmpl	$MAX_MATCH, %eax
+		jge	LenMaximum
+
+/* If the length of the match is not longer than the best match we	*/
+/* have so far, then forget it and return to the lookup loop.		*/
+
+		movl	deflatestate(%esp), %edx
+		movl	bestlen(%esp), %ebx
+		cmpl	%ebx, %eax
+		jg	LongerMatch
+		movl	chainlenscanend(%esp), %ebx
+		movl	windowbestlen(%esp), %esi
+		movl	dsPrev(%edx), %edi
+		movl	wmask(%esp), %edx
+		andl	%ecx, %edx
+		jmp	LookupLoop
+
+/*         s->match_start = cur_match;					*/
+/*         best_len = len;						*/
+/*         if (len >= nice_match) break;				*/
+/*         scan_end = *(ushf*)(scan+best_len-1);			*/
+
+LongerMatch:	movl	nicematch(%esp), %ebx
+		movl	%eax, bestlen(%esp)
+		movl	%ecx, dsMatchStart(%edx)
+		cmpl	%ebx, %eax
+		jge	LeaveNow
+		movl	window(%esp), %esi
+		addl	%eax, %esi
+		movl	%esi, windowbestlen(%esp)
+		movl	chainlenscanend(%esp), %ebx
+		movw	-1(%edi,%eax), %bx
+		movl	dsPrev(%edx), %edi
+		movl	%ebx, chainlenscanend(%esp)
+		movl	wmask(%esp), %edx
+		andl	%ecx, %edx
+		jmp	LookupLoop
+
+/* Accept the current string, with the maximum possible length.		*/
+
+LenMaximum:	movl	deflatestate(%esp), %edx
+		movl	$MAX_MATCH, bestlen(%esp)
+		movl	%ecx, dsMatchStart(%edx)
+
+/* if ((uInt)best_len <= s->lookahead) return (uInt)best_len;		*/
+/* return s->lookahead;							*/
+
+LeaveNow:
+		movl	deflatestate(%esp), %edx
+		movl	bestlen(%esp), %ebx
+		movl	dsLookahead(%edx), %eax
+		cmpl	%eax, %ebx
+		jg	LookaheadRet
+		movl	%ebx, %eax
+LookaheadRet:
+
+/* Restore the stack and return from whence we came.			*/
+
+		addl	$LocalVarsSize, %esp
+		popl	%ebx
+		popl	%esi
+		popl	%edi
+		popl	%ebp
+match_init:	ret
diff --git a/gs/zlib/contrib/asm686/README.686 b/gs/zlib/contrib/asm686/README.686
new file mode 100644
index 000000000..a593f23af
--- /dev/null
+++ b/gs/zlib/contrib/asm686/README.686
@@ -0,0 +1,34 @@
+This is a patched version of zlib, modified to use
+Pentium-Pro-optimized assembly code in the deflation algorithm. The
+files changed/added by this patch are:
+
+README.686
+match.S
+
+The speedup that this patch provides varies, depending on whether the
+compiler used to build the original version of zlib falls afoul of the
+PPro's speed traps. My own tests show a speedup of around 10-20% at
+the default compression level, and 20-30% using -9, against a version
+compiled using gcc 2.7.2.3. Your mileage may vary.
+
+Note that this code has been tailored for the PPro/PII in particular,
+and will not perform particuarly well on a Pentium.
+
+If you are using an assembler other than GNU as, you will have to
+translate match.S to use your assembler's syntax. (Have fun.)
+
+Brian Raiter
+breadbox@muppetlabs.com
+April, 1998
+
+
+Added for zlib 1.1.3:
+
+The patches come from
+http://www.muppetlabs.com/~breadbox/software/assembly.html
+
+To compile zlib with this asm file, copy match.S to the zlib directory
+then do:
+
+CFLAGS="-O3 -DASMV" ./configure
+make OBJA=match.o
diff --git a/gs/zlib/contrib/asm686/match.S b/gs/zlib/contrib/asm686/match.S
new file mode 100644
index 000000000..5c3e9ee36
--- /dev/null
+++ b/gs/zlib/contrib/asm686/match.S
@@ -0,0 +1,329 @@
+/* match.s -- Pentium-Pro-optimized version of longest_match()
+ * Written for zlib 1.1.2
+ * Copyright (C) 1998 Brian Raiter <breadbox@muppetlabs.com>
+ *
+ * This is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License.
+ */
+
+#ifndef NO_UNDERLINE
+#define	match_init	_match_init
+#define	longest_match	_longest_match
+#endif
+
+#define	MAX_MATCH	(258)
+#define	MIN_MATCH	(3)
+#define	MIN_LOOKAHEAD	(MAX_MATCH + MIN_MATCH + 1)
+#define	MAX_MATCH_8	((MAX_MATCH + 7) & ~7)
+
+/* stack frame offsets */
+
+#define	chainlenwmask		0	/* high word: current chain len	*/
+					/* low word: s->wmask		*/
+#define	window			4	/* local copy of s->window	*/
+#define	windowbestlen		8	/* s->window + bestlen		*/
+#define	scanstart		16	/* first two bytes of string	*/
+#define	scanend			12	/* last two bytes of string	*/
+#define	scanalign		20	/* dword-misalignment of string	*/
+#define	nicematch		24	/* a good enough match size	*/
+#define	bestlen			28	/* size of best match so far	*/
+#define	scan			32	/* ptr to string wanting match	*/
+
+#define	LocalVarsSize		(36)
+/*	saved ebx		36 */
+/*	saved edi		40 */
+/*	saved esi		44 */
+/*	saved ebp		48 */
+/*	return address		52 */
+#define	deflatestate		56	/* the function arguments	*/
+#define	curmatch		60
+
+/* All the +zlib1222add offsets are due to the addition of fields
+ *  in zlib in the deflate_state structure since the asm code was first written
+ * (if you compile with zlib 1.0.4 or older, use "zlib1222add equ (-4)").
+ * (if you compile with zlib between 1.0.5 and 1.2.2.1, use "zlib1222add equ 0").
+ * if you compile with zlib 1.2.2.2 or later , use "zlib1222add equ 8").
+ */
+
+#define zlib1222add		(8)
+
+#define	dsWSize			(36+zlib1222add)
+#define	dsWMask			(44+zlib1222add)
+#define	dsWindow		(48+zlib1222add)
+#define	dsPrev			(56+zlib1222add)
+#define	dsMatchLen		(88+zlib1222add)
+#define	dsPrevMatch		(92+zlib1222add)
+#define	dsStrStart		(100+zlib1222add)
+#define	dsMatchStart		(104+zlib1222add)
+#define	dsLookahead		(108+zlib1222add)
+#define	dsPrevLen		(112+zlib1222add)
+#define	dsMaxChainLen		(116+zlib1222add)
+#define	dsGoodMatch		(132+zlib1222add)
+#define	dsNiceMatch		(136+zlib1222add)
+
+
+.file "match.S"
+
+.globl	match_init, longest_match
+
+.text
+
+/* uInt longest_match(deflate_state *deflatestate, IPos curmatch) */
+
+longest_match:
+
+/* Save registers that the compiler may be using, and adjust %esp to	*/
+/* make room for our stack frame.					*/
+
+		pushl	%ebp
+		pushl	%edi
+		pushl	%esi
+		pushl	%ebx
+		subl	$LocalVarsSize, %esp
+
+/* Retrieve the function arguments. %ecx will hold cur_match		*/
+/* throughout the entire function. %edx will hold the pointer to the	*/
+/* deflate_state structure during the function's setup (before		*/
+/* entering the main loop).						*/
+
+		movl	deflatestate(%esp), %edx
+		movl	curmatch(%esp), %ecx
+
+/* uInt wmask = s->w_mask;						*/
+/* unsigned chain_length = s->max_chain_length;				*/
+/* if (s->prev_length >= s->good_match) {				*/
+/*     chain_length >>= 2;						*/
+/* }									*/
+
+		movl	dsPrevLen(%edx), %eax
+		movl	dsGoodMatch(%edx), %ebx
+		cmpl	%ebx, %eax
+		movl	dsWMask(%edx), %eax
+		movl	dsMaxChainLen(%edx), %ebx
+		jl	LastMatchGood
+		shrl	$2, %ebx
+LastMatchGood:
+
+/* chainlen is decremented once beforehand so that the function can	*/
+/* use the sign flag instead of the zero flag for the exit test.	*/
+/* It is then shifted into the high word, to make room for the wmask	*/
+/* value, which it will always accompany.				*/
+
+		decl	%ebx
+		shll	$16, %ebx
+		orl	%eax, %ebx
+		movl	%ebx, chainlenwmask(%esp)
+
+/* if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;	*/
+
+		movl	dsNiceMatch(%edx), %eax
+		movl	dsLookahead(%edx), %ebx
+		cmpl	%eax, %ebx
+		jl	LookaheadLess
+		movl	%eax, %ebx
+LookaheadLess:	movl	%ebx, nicematch(%esp)
+
+/* register Bytef *scan = s->window + s->strstart;			*/
+
+		movl	dsWindow(%edx), %esi
+		movl	%esi, window(%esp)
+		movl	dsStrStart(%edx), %ebp
+		lea	(%esi,%ebp), %edi
+		movl	%edi, scan(%esp)
+
+/* Determine how many bytes the scan ptr is off from being		*/
+/* dword-aligned.							*/
+
+		movl	%edi, %eax
+		negl	%eax
+		andl	$3, %eax
+		movl	%eax, scanalign(%esp)
+
+/* IPos limit = s->strstart > (IPos)MAX_DIST(s) ?			*/
+/*     s->strstart - (IPos)MAX_DIST(s) : NIL;				*/
+
+		movl	dsWSize(%edx), %eax
+		subl	$MIN_LOOKAHEAD, %eax
+		subl	%eax, %ebp
+		jg	LimitPositive
+		xorl	%ebp, %ebp
+LimitPositive:
+
+/* int best_len = s->prev_length;					*/
+
+		movl	dsPrevLen(%edx), %eax
+		movl	%eax, bestlen(%esp)
+
+/* Store the sum of s->window + best_len in %esi locally, and in %esi.	*/
+
+		addl	%eax, %esi
+		movl	%esi, windowbestlen(%esp)
+
+/* register ush scan_start = *(ushf*)scan;				*/
+/* register ush scan_end   = *(ushf*)(scan+best_len-1);			*/
+/* Posf *prev = s->prev;						*/
+
+		movzwl	(%edi), %ebx
+		movl	%ebx, scanstart(%esp)
+		movzwl	-1(%edi,%eax), %ebx
+		movl	%ebx, scanend(%esp)
+		movl	dsPrev(%edx), %edi
+
+/* Jump into the main loop.						*/
+
+		movl	chainlenwmask(%esp), %edx
+		jmp	LoopEntry
+
+.balign 16
+
+/* do {
+ *     match = s->window + cur_match;
+ *     if (*(ushf*)(match+best_len-1) != scan_end ||
+ *         *(ushf*)match != scan_start) continue;
+ *     [...]
+ * } while ((cur_match = prev[cur_match & wmask]) > limit
+ *          && --chain_length != 0);
+ *
+ * Here is the inner loop of the function. The function will spend the
+ * majority of its time in this loop, and majority of that time will
+ * be spent in the first ten instructions.
+ *
+ * Within this loop:
+ * %ebx = scanend
+ * %ecx = curmatch
+ * %edx = chainlenwmask - i.e., ((chainlen << 16) | wmask)
+ * %esi = windowbestlen - i.e., (window + bestlen)
+ * %edi = prev
+ * %ebp = limit
+ */
+LookupLoop:
+		andl	%edx, %ecx
+		movzwl	(%edi,%ecx,2), %ecx
+		cmpl	%ebp, %ecx
+		jbe	LeaveNow
+		subl	$0x00010000, %edx
+		js	LeaveNow
+LoopEntry:	movzwl	-1(%esi,%ecx), %eax
+		cmpl	%ebx, %eax
+		jnz	LookupLoop
+		movl	window(%esp), %eax
+		movzwl	(%eax,%ecx), %eax
+		cmpl	scanstart(%esp), %eax
+		jnz	LookupLoop
+
+/* Store the current value of chainlen.					*/
+
+		movl	%edx, chainlenwmask(%esp)
+
+/* Point %edi to the string under scrutiny, and %esi to the string we	*/
+/* are hoping to match it up with. In actuality, %esi and %edi are	*/
+/* both pointed (MAX_MATCH_8 - scanalign) bytes ahead, and %edx is	*/
+/* initialized to -(MAX_MATCH_8 - scanalign).				*/
+
+		movl	window(%esp), %esi
+		movl	scan(%esp), %edi
+		addl	%ecx, %esi
+		movl	scanalign(%esp), %eax
+		movl	$(-MAX_MATCH_8), %edx
+		lea	MAX_MATCH_8(%edi,%eax), %edi
+		lea	MAX_MATCH_8(%esi,%eax), %esi
+
+/* Test the strings for equality, 8 bytes at a time. At the end,
+ * adjust %edx so that it is offset to the exact byte that mismatched.
+ *
+ * We already know at this point that the first three bytes of the
+ * strings match each other, and they can be safely passed over before
+ * starting the compare loop. So what this code does is skip over 0-3
+ * bytes, as much as necessary in order to dword-align the %edi
+ * pointer. (%esi will still be misaligned three times out of four.)
+ *
+ * It should be confessed that this loop usually does not represent
+ * much of the total running time. Replacing it with a more
+ * straightforward "rep cmpsb" would not drastically degrade
+ * performance.
+ */
+LoopCmps:
+		movl	(%esi,%edx), %eax
+		xorl	(%edi,%edx), %eax
+		jnz	LeaveLoopCmps
+		movl	4(%esi,%edx), %eax
+		xorl	4(%edi,%edx), %eax
+		jnz	LeaveLoopCmps4
+		addl	$8, %edx
+		jnz	LoopCmps
+		jmp	LenMaximum
+LeaveLoopCmps4:	addl	$4, %edx
+LeaveLoopCmps:	testl	$0x0000FFFF, %eax
+		jnz	LenLower
+		addl	$2, %edx
+		shrl	$16, %eax
+LenLower:	subb	$1, %al
+		adcl	$0, %edx
+
+/* Calculate the length of the match. If it is longer than MAX_MATCH,	*/
+/* then automatically accept it as the best possible match and leave.	*/
+
+		lea	(%edi,%edx), %eax
+		movl	scan(%esp), %edi
+		subl	%edi, %eax
+		cmpl	$MAX_MATCH, %eax
+		jge	LenMaximum
+
+/* If the length of the match is not longer than the best match we	*/
+/* have so far, then forget it and return to the lookup loop.		*/
+
+		movl	deflatestate(%esp), %edx
+		movl	bestlen(%esp), %ebx
+		cmpl	%ebx, %eax
+		jg	LongerMatch
+		movl	windowbestlen(%esp), %esi
+		movl	dsPrev(%edx), %edi
+		movl	scanend(%esp), %ebx
+		movl	chainlenwmask(%esp), %edx
+		jmp	LookupLoop
+
+/*         s->match_start = cur_match;					*/
+/*         best_len = len;						*/
+/*         if (len >= nice_match) break;				*/
+/*         scan_end = *(ushf*)(scan+best_len-1);			*/
+
+LongerMatch:	movl	nicematch(%esp), %ebx
+		movl	%eax, bestlen(%esp)
+		movl	%ecx, dsMatchStart(%edx)
+		cmpl	%ebx, %eax
+		jge	LeaveNow
+		movl	window(%esp), %esi
+		addl	%eax, %esi
+		movl	%esi, windowbestlen(%esp)
+		movzwl	-1(%edi,%eax), %ebx
+		movl	dsPrev(%edx), %edi
+		movl	%ebx, scanend(%esp)
+		movl	chainlenwmask(%esp), %edx
+		jmp	LookupLoop
+
+/* Accept the current string, with the maximum possible length.		*/
+
+LenMaximum:	movl	deflatestate(%esp), %edx
+		movl	$MAX_MATCH, bestlen(%esp)
+		movl	%ecx, dsMatchStart(%edx)
+
+/* if ((uInt)best_len <= s->lookahead) return (uInt)best_len;		*/
+/* return s->lookahead;							*/
+
+LeaveNow:
+		movl	deflatestate(%esp), %edx
+		movl	bestlen(%esp), %ebx
+		movl	dsLookahead(%edx), %eax
+		cmpl	%eax, %ebx
+		jg	LookaheadRet
+		movl	%ebx, %eax
+LookaheadRet:
+
+/* Restore the stack and return from whence we came.			*/
+
+		addl	$LocalVarsSize, %esp
+		popl	%ebx
+		popl	%esi
+		popl	%edi
+		popl	%ebp
+match_init:	ret
diff --git a/gs/zlib/contrib/blast/Makefile b/gs/zlib/contrib/blast/Makefile
new file mode 100644
index 000000000..9be80bafe
--- /dev/null
+++ b/gs/zlib/contrib/blast/Makefile
@@ -0,0 +1,8 @@
+blast: blast.c blast.h
+	cc -DTEST -o blast blast.c
+
+test: blast
+	blast < test.pk | cmp - test.txt
+
+clean:
+	rm -f blast blast.o
diff --git a/gs/zlib/contrib/blast/README b/gs/zlib/contrib/blast/README
new file mode 100644
index 000000000..e3a60b3f5
--- /dev/null
+++ b/gs/zlib/contrib/blast/README
@@ -0,0 +1,4 @@
+Read blast.h for purpose and usage.
+
+Mark Adler
+madler@alumni.caltech.edu
diff --git a/gs/zlib/contrib/blast/blast.c b/gs/zlib/contrib/blast/blast.c
new file mode 100644
index 000000000..4ce697a41
--- /dev/null
+++ b/gs/zlib/contrib/blast/blast.c
@@ -0,0 +1,444 @@
+/* blast.c
+ * Copyright (C) 2003 Mark Adler
+ * For conditions of distribution and use, see copyright notice in blast.h
+ * version 1.1, 16 Feb 2003
+ *
+ * blast.c decompresses data compressed by the PKWare Compression Library.
+ * This function provides functionality similar to the explode() function of
+ * the PKWare library, hence the name "blast".
+ *
+ * This decompressor is based on the excellent format description provided by
+ * Ben Rudiak-Gould in comp.compression on August 13, 2001.  Interestingly, the
+ * example Ben provided in the post is incorrect.  The distance 110001 should
+ * instead be 111000.  When corrected, the example byte stream becomes:
+ *
+ *    00 04 82 24 25 8f 80 7f
+ *
+ * which decompresses to "AIAIAIAIAIAIA" (without the quotes).
+ */
+
+/*
+ * Change history:
+ *
+ * 1.0  12 Feb 2003     - First version
+ * 1.1  16 Feb 2003     - Fixed distance check for > 4 GB uncompressed data
+ */
+
+#include <setjmp.h>             /* for setjmp(), longjmp(), and jmp_buf */
+#include "blast.h"              /* prototype for blast() */
+
+#define local static            /* for local function definitions */
+#define MAXBITS 13              /* maximum code length */
+#define MAXWIN 4096             /* maximum window size */
+
+/* input and output state */
+struct state {
+    /* input state */
+    blast_in infun;             /* input function provided by user */
+    void *inhow;                /* opaque information passed to infun() */
+    unsigned char *in;          /* next input location */
+    unsigned left;              /* available input at in */
+    int bitbuf;                 /* bit buffer */
+    int bitcnt;                 /* number of bits in bit buffer */
+
+    /* input limit error return state for bits() and decode() */
+    jmp_buf env;
+
+    /* output state */
+    blast_out outfun;           /* output function provided by user */
+    void *outhow;               /* opaque information passed to outfun() */
+    unsigned next;              /* index of next write location in out[] */
+    int first;                  /* true to check distances (for first 4K) */
+    unsigned char out[MAXWIN];  /* output buffer and sliding window */
+};
+
+/*
+ * Return need bits from the input stream.  This always leaves less than
+ * eight bits in the buffer.  bits() works properly for need == 0.
+ *
+ * Format notes:
+ *
+ * - Bits are stored in bytes from the least significant bit to the most
+ *   significant bit.  Therefore bits are dropped from the bottom of the bit
+ *   buffer, using shift right, and new bytes are appended to the top of the
+ *   bit buffer, using shift left.
+ */
+local int bits(struct state *s, int need)
+{
+    int val;            /* bit accumulator */
+
+    /* load at least need bits into val */
+    val = s->bitbuf;
+    while (s->bitcnt < need) {
+        if (s->left == 0) {
+            s->left = s->infun(s->inhow, &(s->in));
+            if (s->left == 0) longjmp(s->env, 1);       /* out of input */
+        }
+        val |= (int)(*(s->in)++) << s->bitcnt;          /* load eight bits */
+        s->left--;
+        s->bitcnt += 8;
+    }
+
+    /* drop need bits and update buffer, always zero to seven bits left */
+    s->bitbuf = val >> need;
+    s->bitcnt -= need;
+
+    /* return need bits, zeroing the bits above that */
+    return val & ((1 << need) - 1);
+}
+
+/*
+ * Huffman code decoding tables.  count[1..MAXBITS] is the number of symbols of
+ * each length, which for a canonical code are stepped through in order.
+ * symbol[] are the symbol values in canonical order, where the number of
+ * entries is the sum of the counts in count[].  The decoding process can be
+ * seen in the function decode() below.
+ */
+struct huffman {
+    short *count;       /* number of symbols of each length */
+    short *symbol;      /* canonically ordered symbols */
+};
+
+/*
+ * Decode a code from the stream s using huffman table h.  Return the symbol or
+ * a negative value if there is an error.  If all of the lengths are zero, i.e.
+ * an empty code, or if the code is incomplete and an invalid code is received,
+ * then -9 is returned after reading MAXBITS bits.
+ *
+ * Format notes:
+ *
+ * - The codes as stored in the compressed data are bit-reversed relative to
+ *   a simple integer ordering of codes of the same lengths.  Hence below the
+ *   bits are pulled from the compressed data one at a time and used to
+ *   build the code value reversed from what is in the stream in order to
+ *   permit simple integer comparisons for decoding.
+ *
+ * - The first code for the shortest length is all ones.  Subsequent codes of
+ *   the same length are simply integer decrements of the previous code.  When
+ *   moving up a length, a one bit is appended to the code.  For a complete
+ *   code, the last code of the longest length will be all zeros.  To support
+ *   this ordering, the bits pulled during decoding are inverted to apply the
+ *   more "natural" ordering starting with all zeros and incrementing.
+ */
+local int decode(struct state *s, struct huffman *h)
+{
+    int len;            /* current number of bits in code */
+    int code;           /* len bits being decoded */
+    int first;          /* first code of length len */
+    int count;          /* number of codes of length len */
+    int index;          /* index of first code of length len in symbol table */
+    int bitbuf;         /* bits from stream */
+    int left;           /* bits left in next or left to process */
+    short *next;        /* next number of codes */
+
+    bitbuf = s->bitbuf;
+    left = s->bitcnt;
+    code = first = index = 0;
+    len = 1;
+    next = h->count + 1;
+    while (1) {
+        while (left--) {
+            code |= (bitbuf & 1) ^ 1;   /* invert code */
+            bitbuf >>= 1;
+            count = *next++;
+            if (code < first + count) { /* if length len, return symbol */
+                s->bitbuf = bitbuf;
+                s->bitcnt = (s->bitcnt - len) & 7;
+                return h->symbol[index + (code - first)];
+            }
+            index += count;             /* else update for next length */
+            first += count;
+            first <<= 1;
+            code <<= 1;
+            len++;
+        }
+        left = (MAXBITS+1) - len;
+        if (left == 0) break;
+        if (s->left == 0) {
+            s->left = s->infun(s->inhow, &(s->in));
+            if (s->left == 0) longjmp(s->env, 1);       /* out of input */
+        }
+        bitbuf = *(s->in)++;
+        s->left--;
+        if (left > 8) left = 8;
+    }
+    return -9;                          /* ran out of codes */
+}
+
+/*
+ * Given a list of repeated code lengths rep[0..n-1], where each byte is a
+ * count (high four bits + 1) and a code length (low four bits), generate the
+ * list of code lengths.  This compaction reduces the size of the object code.
+ * Then given the list of code lengths length[0..n-1] representing a canonical
+ * Huffman code for n symbols, construct the tables required to decode those
+ * codes.  Those tables are the number of codes of each length, and the symbols
+ * sorted by length, retaining their original order within each length.  The
+ * return value is zero for a complete code set, negative for an over-
+ * subscribed code set, and positive for an incomplete code set.  The tables
+ * can be used if the return value is zero or positive, but they cannot be used
+ * if the return value is negative.  If the return value is zero, it is not
+ * possible for decode() using that table to return an error--any stream of
+ * enough bits will resolve to a symbol.  If the return value is positive, then
+ * it is possible for decode() using that table to return an error for received
+ * codes past the end of the incomplete lengths.
+ */
+local int construct(struct huffman *h, const unsigned char *rep, int n)
+{
+    int symbol;         /* current symbol when stepping through length[] */
+    int len;            /* current length when stepping through h->count[] */
+    int left;           /* number of possible codes left of current length */
+    short offs[MAXBITS+1];      /* offsets in symbol table for each length */
+    short length[256];  /* code lengths */
+
+    /* convert compact repeat counts into symbol bit length list */
+    symbol = 0;
+    do {
+        len = *rep++;
+        left = (len >> 4) + 1;
+        len &= 15;
+        do {
+            length[symbol++] = len;
+        } while (--left);
+    } while (--n);
+    n = symbol;
+
+    /* count number of codes of each length */
+    for (len = 0; len <= MAXBITS; len++)
+        h->count[len] = 0;
+    for (symbol = 0; symbol < n; symbol++)
+        (h->count[length[symbol]])++;   /* assumes lengths are within bounds */
+    if (h->count[0] == n)               /* no codes! */
+        return 0;                       /* complete, but decode() will fail */
+
+    /* check for an over-subscribed or incomplete set of lengths */
+    left = 1;                           /* one possible code of zero length */
+    for (len = 1; len <= MAXBITS; len++) {
+        left <<= 1;                     /* one more bit, double codes left */
+        left -= h->count[len];          /* deduct count from possible codes */
+        if (left < 0) return left;      /* over-subscribed--return negative */
+    }                                   /* left > 0 means incomplete */
+
+    /* generate offsets into symbol table for each length for sorting */
+    offs[1] = 0;
+    for (len = 1; len < MAXBITS; len++)
+        offs[len + 1] = offs[len] + h->count[len];
+
+    /*
+     * put symbols in table sorted by length, by symbol order within each
+     * length
+     */
+    for (symbol = 0; symbol < n; symbol++)
+        if (length[symbol] != 0)
+            h->symbol[offs[length[symbol]]++] = symbol;
+
+    /* return zero for complete set, positive for incomplete set */
+    return left;
+}
+
+/*
+ * Decode PKWare Compression Library stream.
+ *
+ * Format notes:
+ *
+ * - First byte is 0 if literals are uncoded or 1 if they are coded.  Second
+ *   byte is 4, 5, or 6 for the number of extra bits in the distance code.
+ *   This is the base-2 logarithm of the dictionary size minus six.
+ *
+ * - Compressed data is a combination of literals and length/distance pairs
+ *   terminated by an end code.  Literals are either Huffman coded or
+ *   uncoded bytes.  A length/distance pair is a coded length followed by a
+ *   coded distance to represent a string that occurs earlier in the
+ *   uncompressed data that occurs again at the current location.
+ *
+ * - A bit preceding a literal or length/distance pair indicates which comes
+ *   next, 0 for literals, 1 for length/distance.
+ *
+ * - If literals are uncoded, then the next eight bits are the literal, in the
+ *   normal bit order in th stream, i.e. no bit-reversal is needed. Similarly,
+ *   no bit reversal is needed for either the length extra bits or the distance
+ *   extra bits.
+ *
+ * - Literal bytes are simply written to the output.  A length/distance pair is
+ *   an instruction to copy previously uncompressed bytes to the output.  The
+ *   copy is from distance bytes back in the output stream, copying for length
+ *   bytes.
+ *
+ * - Distances pointing before the beginning of the output data are not
+ *   permitted.
+ *
+ * - Overlapped copies, where the length is greater than the distance, are
+ *   allowed and common.  For example, a distance of one and a length of 518
+ *   simply copies the last byte 518 times.  A distance of four and a length of
+ *   twelve copies the last four bytes three times.  A simple forward copy
+ *   ignoring whether the length is greater than the distance or not implements
+ *   this correctly.
+ */
+local int decomp(struct state *s)
+{
+    int lit;            /* true if literals are coded */
+    int dict;           /* log2(dictionary size) - 6 */
+    int symbol;         /* decoded symbol, extra bits for distance */
+    int len;            /* length for copy */
+    int dist;           /* distance for copy */
+    int copy;           /* copy counter */
+    unsigned char *from, *to;   /* copy pointers */
+    static int virgin = 1;                              /* build tables once */
+    static short litcnt[MAXBITS+1], litsym[256];        /* litcode memory */
+    static short lencnt[MAXBITS+1], lensym[16];         /* lencode memory */
+    static short distcnt[MAXBITS+1], distsym[64];       /* distcode memory */
+    static struct huffman litcode = {litcnt, litsym};   /* length code */
+    static struct huffman lencode = {lencnt, lensym};   /* length code */
+    static struct huffman distcode = {distcnt, distsym};/* distance code */
+        /* bit lengths of literal codes */
+    static const unsigned char litlen[] = {
+        11, 124, 8, 7, 28, 7, 188, 13, 76, 4, 10, 8, 12, 10, 12, 10, 8, 23, 8,
+        9, 7, 6, 7, 8, 7, 6, 55, 8, 23, 24, 12, 11, 7, 9, 11, 12, 6, 7, 22, 5,
+        7, 24, 6, 11, 9, 6, 7, 22, 7, 11, 38, 7, 9, 8, 25, 11, 8, 11, 9, 12,
+        8, 12, 5, 38, 5, 38, 5, 11, 7, 5, 6, 21, 6, 10, 53, 8, 7, 24, 10, 27,
+        44, 253, 253, 253, 252, 252, 252, 13, 12, 45, 12, 45, 12, 61, 12, 45,
+        44, 173};
+        /* bit lengths of length codes 0..15 */
+    static const unsigned char lenlen[] = {2, 35, 36, 53, 38, 23};
+        /* bit lengths of distance codes 0..63 */
+    static const unsigned char distlen[] = {2, 20, 53, 230, 247, 151, 248};
+    static const short base[16] = {     /* base for length codes */
+        3, 2, 4, 5, 6, 7, 8, 9, 10, 12, 16, 24, 40, 72, 136, 264};
+    static const char extra[16] = {     /* extra bits for length codes */
+        0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8};
+
+    /* set up decoding tables (once--might not be thread-safe) */
+    if (virgin) {
+        construct(&litcode, litlen, sizeof(litlen));
+        construct(&lencode, lenlen, sizeof(lenlen));
+        construct(&distcode, distlen, sizeof(distlen));
+        virgin = 0;
+    }
+
+    /* read header */
+    lit = bits(s, 8);
+    if (lit > 1) return -1;
+    dict = bits(s, 8);
+    if (dict < 4 || dict > 6) return -2;
+
+    /* decode literals and length/distance pairs */
+    do {
+        if (bits(s, 1)) {
+            /* get length */
+            symbol = decode(s, &lencode);
+            len = base[symbol] + bits(s, extra[symbol]);
+            if (len == 519) break;              /* end code */
+
+            /* get distance */
+            symbol = len == 2 ? 2 : dict;
+            dist = decode(s, &distcode) << symbol;
+            dist += bits(s, symbol);
+            dist++;
+            if (s->first && dist > s->next)
+                return -3;              /* distance too far back */
+
+            /* copy length bytes from distance bytes back */
+            do {
+                to = s->out + s->next;
+                from = to - dist;
+                copy = MAXWIN;
+                if (s->next < dist) {
+                    from += copy;
+                    copy = dist;
+                }
+                copy -= s->next;
+                if (copy > len) copy = len;
+                len -= copy;
+                s->next += copy;
+                do {
+                    *to++ = *from++;
+                } while (--copy);
+                if (s->next == MAXWIN) {
+                    if (s->outfun(s->outhow, s->out, s->next)) return 1;
+                    s->next = 0;
+                    s->first = 0;
+                }
+            } while (len != 0);
+        }
+        else {
+            /* get literal and write it */
+            symbol = lit ? decode(s, &litcode) : bits(s, 8);
+            s->out[s->next++] = symbol;
+            if (s->next == MAXWIN) {
+                if (s->outfun(s->outhow, s->out, s->next)) return 1;
+                s->next = 0;
+                s->first = 0;
+            }
+        }
+    } while (1);
+    return 0;
+}
+
+/* See comments in blast.h */
+int blast(blast_in infun, void *inhow, blast_out outfun, void *outhow)
+{
+    struct state s;             /* input/output state */
+    int err;                    /* return value */
+
+    /* initialize input state */
+    s.infun = infun;
+    s.inhow = inhow;
+    s.left = 0;
+    s.bitbuf = 0;
+    s.bitcnt = 0;
+
+    /* initialize output state */
+    s.outfun = outfun;
+    s.outhow = outhow;
+    s.next = 0;
+    s.first = 1;
+
+    /* return if bits() or decode() tries to read past available input */
+    if (setjmp(s.env) != 0)             /* if came back here via longjmp(), */
+        err = 2;                        /*  then skip decomp(), return error */
+    else
+        err = decomp(&s);               /* decompress */
+
+    /* write any leftover output and update the error code if needed */
+    if (err != 1 && s.next && s.outfun(s.outhow, s.out, s.next) && err == 0)
+        err = 1;
+    return err;
+}
+
+#ifdef TEST
+/* Example of how to use blast() */
+#include <stdio.h>
+#include <stdlib.h>
+
+#define CHUNK 16384
+
+local unsigned inf(void *how, unsigned char **buf)
+{
+    static unsigned char hold[CHUNK];
+
+    *buf = hold;
+    return fread(hold, 1, CHUNK, (FILE *)how);
+}
+
+local int outf(void *how, unsigned char *buf, unsigned len)
+{
+    return fwrite(buf, 1, len, (FILE *)how) != len;
+}
+
+/* Decompress a PKWare Compression Library stream from stdin to stdout */
+int main(void)
+{
+    int ret, n;
+
+    /* decompress to stdout */
+    ret = blast(inf, stdin, outf, stdout);
+    if (ret != 0) fprintf(stderr, "blast error: %d\n", ret);
+
+    /* see if there are any leftover bytes */
+    n = 0;
+    while (getchar() != EOF) n++;
+    if (n) fprintf(stderr, "blast warning: %d unused bytes of input\n", n);
+
+    /* return blast() error code */
+    return ret;
+}
+#endif
diff --git a/gs/zlib/contrib/blast/blast.h b/gs/zlib/contrib/blast/blast.h
new file mode 100644
index 000000000..ce9e5410f
--- /dev/null
+++ b/gs/zlib/contrib/blast/blast.h
@@ -0,0 +1,71 @@
+/* blast.h -- interface for blast.c
+  Copyright (C) 2003 Mark Adler
+  version 1.1, 16 Feb 2003
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the author be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+
+  Mark Adler    madler@alumni.caltech.edu
+ */
+
+
+/*
+ * blast() decompresses the PKWare Data Compression Library (DCL) compressed
+ * format.  It provides the same functionality as the explode() function in
+ * that library.  (Note: PKWare overused the "implode" verb, and the format
+ * used by their library implode() function is completely different and
+ * incompatible with the implode compression method supported by PKZIP.)
+ */
+
+
+typedef unsigned (*blast_in)(void *how, unsigned char **buf);
+typedef int (*blast_out)(void *how, unsigned char *buf, unsigned len);
+/* Definitions for input/output functions passed to blast().  See below for
+ * what the provided functions need to do.
+ */
+
+
+int blast(blast_in infun, void *inhow, blast_out outfun, void *outhow);
+/* Decompress input to output using the provided infun() and outfun() calls.
+ * On success, the return value of blast() is zero.  If there is an error in
+ * the source data, i.e. it is not in the proper format, then a negative value
+ * is returned.  If there is not enough input available or there is not enough
+ * output space, then a positive error is returned.
+ *
+ * The input function is invoked: len = infun(how, &buf), where buf is set by
+ * infun() to point to the input buffer, and infun() returns the number of
+ * available bytes there.  If infun() returns zero, then blast() returns with
+ * an input error.  (blast() only asks for input if it needs it.)  inhow is for
+ * use by the application to pass an input descriptor to infun(), if desired.
+ *
+ * The output function is invoked: err = outfun(how, buf, len), where the bytes
+ * to be written are buf[0..len-1].  If err is not zero, then blast() returns
+ * with an output error.  outfun() is always called with len <= 4096.  outhow
+ * is for use by the application to pass an output descriptor to outfun(), if
+ * desired.
+ *
+ * The return codes are:
+ *
+ *   2:  ran out of input before completing decompression
+ *   1:  output error before completing decompression
+ *   0:  successful decompression
+ *  -1:  literal flag not zero or one
+ *  -2:  dictionary size not in 4..6
+ *  -3:  distance is too far back
+ *
+ * At the bottom of blast.c is an example program that uses blast() that can be
+ * compiled to produce a command-line decompression filter by defining TEST.
+ */
diff --git a/gs/zlib/contrib/blast/test.pk b/gs/zlib/contrib/blast/test.pk
new file mode 100644
index 000000000..be10b2bbb
--- /dev/null
+++ b/gs/zlib/contrib/blast/test.pk
diff --git a/gs/zlib/contrib/blast/test.txt b/gs/zlib/contrib/blast/test.txt
new file mode 100644
index 000000000..bfdf1c5dc
--- /dev/null
+++ b/gs/zlib/contrib/blast/test.txt
@@ -0,0 +1 @@
+AIAIAIAIAIAIA
\ No newline at end of file
diff --git a/gs/zlib/contrib/delphi/ZLib.pas b/gs/zlib/contrib/delphi/ZLib.pas
new file mode 100644
index 000000000..3f2b8b4a5
--- /dev/null
+++ b/gs/zlib/contrib/delphi/ZLib.pas
@@ -0,0 +1,557 @@
+{*******************************************************}
+{                                                       }
+{       Borland Delphi Supplemental Components          }
+{       ZLIB Data Compression Interface Unit            }
+{                                                       }
+{       Copyright (c) 1997,99 Borland Corporation       }
+{                                                       }
+{*******************************************************}
+
+{ Updated for zlib 1.2.x by Cosmin Truta <cosmint@cs.ubbcluj.ro> }
+
+unit ZLib;
+
+interface
+
+uses SysUtils, Classes;
+
+type
+  TAlloc = function (AppData: Pointer; Items, Size: Integer): Pointer; cdecl;
+  TFree = procedure (AppData, Block: Pointer); cdecl;
+
+  // Internal structure.  Ignore.
+  TZStreamRec = packed record
+    next_in: PChar;       // next input byte
+    avail_in: Integer;    // number of bytes available at next_in
+    total_in: Longint;    // total nb of input bytes read so far
+
+    next_out: PChar;      // next output byte should be put here
+    avail_out: Integer;   // remaining free space at next_out
+    total_out: Longint;   // total nb of bytes output so far
+
+    msg: PChar;           // last error message, NULL if no error
+    internal: Pointer;    // not visible by applications
+
+    zalloc: TAlloc;       // used to allocate the internal state
+    zfree: TFree;         // used to free the internal state
+    AppData: Pointer;     // private data object passed to zalloc and zfree
+
+    data_type: Integer;   // best guess about the data type: ascii or binary
+    adler: Longint;       // adler32 value of the uncompressed data
+    reserved: Longint;    // reserved for future use
+  end;
+
+  // Abstract ancestor class
+  TCustomZlibStream = class(TStream)
+  private
+    FStrm: TStream;
+    FStrmPos: Integer;
+    FOnProgress: TNotifyEvent;
+    FZRec: TZStreamRec;
+    FBuffer: array [Word] of Char;
+  protected
+    procedure Progress(Sender: TObject); dynamic;
+    property OnProgress: TNotifyEvent read FOnProgress write FOnProgress;
+    constructor Create(Strm: TStream);
+  end;
+
+{ TCompressionStream compresses data on the fly as data is written to it, and
+  stores the compressed data to another stream.
+
+  TCompressionStream is write-only and strictly sequential. Reading from the
+  stream will raise an exception. Using Seek to move the stream pointer
+  will raise an exception.
+
+  Output data is cached internally, written to the output stream only when
+  the internal output buffer is full.  All pending output data is flushed
+  when the stream is destroyed.
+
+  The Position property returns the number of uncompressed bytes of
+  data that have been written to the stream so far.
+
+  CompressionRate returns the on-the-fly percentage by which the original
+  data has been compressed:  (1 - (CompressedBytes / UncompressedBytes)) * 100
+  If raw data size = 100 and compressed data size = 25, the CompressionRate
+  is 75%
+
+  The OnProgress event is called each time the output buffer is filled and
+  written to the output stream.  This is useful for updating a progress
+  indicator when you are writing a large chunk of data to the compression
+  stream in a single call.}
+
+
+  TCompressionLevel = (clNone, clFastest, clDefault, clMax);
+
+  TCompressionStream = class(TCustomZlibStream)
+  private
+    function GetCompressionRate: Single;
+  public
+    constructor Create(CompressionLevel: TCompressionLevel; Dest: TStream);
+    destructor Destroy; override;
+    function Read(var Buffer; Count: Longint): Longint; override;
+    function Write(const Buffer; Count: Longint): Longint; override;
+    function Seek(Offset: Longint; Origin: Word): Longint; override;
+    property CompressionRate: Single read GetCompressionRate;
+    property OnProgress;
+  end;
+
+{ TDecompressionStream decompresses data on the fly as data is read from it.
+
+  Compressed data comes from a separate source stream.  TDecompressionStream
+  is read-only and unidirectional; you can seek forward in the stream, but not
+  backwards.  The special case of setting the stream position to zero is
+  allowed.  Seeking forward decompresses data until the requested position in
+  the uncompressed data has been reached.  Seeking backwards, seeking relative
+  to the end of the stream, requesting the size of the stream, and writing to
+  the stream will raise an exception.
+
+  The Position property returns the number of bytes of uncompressed data that
+  have been read from the stream so far.
+
+  The OnProgress event is called each time the internal input buffer of
+  compressed data is exhausted and the next block is read from the input stream.
+  This is useful for updating a progress indicator when you are reading a
+  large chunk of data from the decompression stream in a single call.}
+
+  TDecompressionStream = class(TCustomZlibStream)
+  public
+    constructor Create(Source: TStream);
+    destructor Destroy; override;
+    function Read(var Buffer; Count: Longint): Longint; override;
+    function Write(const Buffer; Count: Longint): Longint; override;
+    function Seek(Offset: Longint; Origin: Word): Longint; override;
+    property OnProgress;
+  end;
+
+
+
+{ CompressBuf compresses data, buffer to buffer, in one call.
+   In: InBuf = ptr to compressed data
+       InBytes = number of bytes in InBuf
+  Out: OutBuf = ptr to newly allocated buffer containing decompressed data
+       OutBytes = number of bytes in OutBuf   }
+procedure CompressBuf(const InBuf: Pointer; InBytes: Integer;
+                      out OutBuf: Pointer; out OutBytes: Integer);
+
+
+{ DecompressBuf decompresses data, buffer to buffer, in one call.
+   In: InBuf = ptr to compressed data
+       InBytes = number of bytes in InBuf
+       OutEstimate = zero, or est. size of the decompressed data
+  Out: OutBuf = ptr to newly allocated buffer containing decompressed data
+       OutBytes = number of bytes in OutBuf   }
+procedure DecompressBuf(const InBuf: Pointer; InBytes: Integer;
+ OutEstimate: Integer; out OutBuf: Pointer; out OutBytes: Integer);
+
+{ DecompressToUserBuf decompresses data, buffer to buffer, in one call.
+   In: InBuf = ptr to compressed data
+       InBytes = number of bytes in InBuf
+  Out: OutBuf = ptr to user-allocated buffer to contain decompressed data
+       BufSize = number of bytes in OutBuf   }
+procedure DecompressToUserBuf(const InBuf: Pointer; InBytes: Integer;
+  const OutBuf: Pointer; BufSize: Integer);
+
+const
+  zlib_version = '1.2.3';
+
+type
+  EZlibError = class(Exception);
+  ECompressionError = class(EZlibError);
+  EDecompressionError = class(EZlibError);
+
+implementation
+
+uses ZLibConst;
+
+const
+  Z_NO_FLUSH      = 0;
+  Z_PARTIAL_FLUSH = 1;
+  Z_SYNC_FLUSH    = 2;
+  Z_FULL_FLUSH    = 3;
+  Z_FINISH        = 4;
+
+  Z_OK            = 0;
+  Z_STREAM_END    = 1;
+  Z_NEED_DICT     = 2;
+  Z_ERRNO         = (-1);
+  Z_STREAM_ERROR  = (-2);
+  Z_DATA_ERROR    = (-3);
+  Z_MEM_ERROR     = (-4);
+  Z_BUF_ERROR     = (-5);
+  Z_VERSION_ERROR = (-6);
+
+  Z_NO_COMPRESSION       =   0;
+  Z_BEST_SPEED           =   1;
+  Z_BEST_COMPRESSION     =   9;
+  Z_DEFAULT_COMPRESSION  = (-1);
+
+  Z_FILTERED            = 1;
+  Z_HUFFMAN_ONLY        = 2;
+  Z_RLE                 = 3;
+  Z_DEFAULT_STRATEGY    = 0;
+
+  Z_BINARY   = 0;
+  Z_ASCII    = 1;
+  Z_UNKNOWN  = 2;
+
+  Z_DEFLATED = 8;
+
+
+{$L adler32.obj}
+{$L compress.obj}
+{$L crc32.obj}
+{$L deflate.obj}
+{$L infback.obj}
+{$L inffast.obj}
+{$L inflate.obj}
+{$L inftrees.obj}
+{$L trees.obj}
+{$L uncompr.obj}
+{$L zutil.obj}
+
+procedure adler32; external;
+procedure compressBound; external;
+procedure crc32; external;
+procedure deflateInit2_; external;
+procedure deflateParams; external;
+
+function _malloc(Size: Integer): Pointer; cdecl;
+begin
+  Result := AllocMem(Size);
+end;
+
+procedure _free(Block: Pointer); cdecl;
+begin
+  FreeMem(Block);
+end;
+
+procedure _memset(P: Pointer; B: Byte; count: Integer); cdecl;
+begin
+  FillChar(P^, count, B);
+end;
+
+procedure _memcpy(dest, source: Pointer; count: Integer); cdecl;
+begin
+  Move(source^, dest^, count);
+end;
+
+
+
+// deflate compresses data
+function deflateInit_(var strm: TZStreamRec; level: Integer; version: PChar;
+  recsize: Integer): Integer; external;
+function deflate(var strm: TZStreamRec; flush: Integer): Integer; external;
+function deflateEnd(var strm: TZStreamRec): Integer; external;
+
+// inflate decompresses data
+function inflateInit_(var strm: TZStreamRec; version: PChar;
+  recsize: Integer): Integer; external;
+function inflate(var strm: TZStreamRec; flush: Integer): Integer; external;
+function inflateEnd(var strm: TZStreamRec): Integer; external;
+function inflateReset(var strm: TZStreamRec): Integer; external;
+
+
+function zlibAllocMem(AppData: Pointer; Items, Size: Integer): Pointer; cdecl;
+begin
+//  GetMem(Result, Items*Size);
+  Result := AllocMem(Items * Size);
+end;
+
+procedure zlibFreeMem(AppData, Block: Pointer); cdecl;
+begin
+  FreeMem(Block);
+end;
+
+{function zlibCheck(code: Integer): Integer;
+begin
+  Result := code;
+  if code < 0 then
+    raise EZlibError.Create('error');    //!!
+end;}
+
+function CCheck(code: Integer): Integer;
+begin
+  Result := code;
+  if code < 0 then
+    raise ECompressionError.Create('error'); //!!
+end;
+
+function DCheck(code: Integer): Integer;
+begin
+  Result := code;
+  if code < 0 then
+    raise EDecompressionError.Create('error');  //!!
+end;
+
+procedure CompressBuf(const InBuf: Pointer; InBytes: Integer;
+                      out OutBuf: Pointer; out OutBytes: Integer);
+var
+  strm: TZStreamRec;
+  P: Pointer;
+begin
+  FillChar(strm, sizeof(strm), 0);
+  strm.zalloc := zlibAllocMem;
+  strm.zfree := zlibFreeMem;
+  OutBytes := ((InBytes + (InBytes div 10) + 12) + 255) and not 255;
+  GetMem(OutBuf, OutBytes);
+  try
+    strm.next_in := InBuf;
+    strm.avail_in := InBytes;
+    strm.next_out := OutBuf;
+    strm.avail_out := OutBytes;
+    CCheck(deflateInit_(strm, Z_BEST_COMPRESSION, zlib_version, sizeof(strm)));
+    try
+      while CCheck(deflate(strm, Z_FINISH)) <> Z_STREAM_END do
+      begin
+        P := OutBuf;
+        Inc(OutBytes, 256);
+        ReallocMem(OutBuf, OutBytes);
+        strm.next_out := PChar(Integer(OutBuf) + (Integer(strm.next_out) - Integer(P)));
+        strm.avail_out := 256;
+      end;
+    finally
+      CCheck(deflateEnd(strm));
+    end;
+    ReallocMem(OutBuf, strm.total_out);
+    OutBytes := strm.total_out;
+  except
+    FreeMem(OutBuf);
+    raise
+  end;
+end;
+
+
+procedure DecompressBuf(const InBuf: Pointer; InBytes: Integer;
+  OutEstimate: Integer; out OutBuf: Pointer; out OutBytes: Integer);
+var
+  strm: TZStreamRec;
+  P: Pointer;
+  BufInc: Integer;
+begin
+  FillChar(strm, sizeof(strm), 0);
+  strm.zalloc := zlibAllocMem;
+  strm.zfree := zlibFreeMem;
+  BufInc := (InBytes + 255) and not 255;
+  if OutEstimate = 0 then
+    OutBytes := BufInc
+  else
+    OutBytes := OutEstimate;
+  GetMem(OutBuf, OutBytes);
+  try
+    strm.next_in := InBuf;
+    strm.avail_in := InBytes;
+    strm.next_out := OutBuf;
+    strm.avail_out := OutBytes;
+    DCheck(inflateInit_(strm, zlib_version, sizeof(strm)));
+    try
+      while DCheck(inflate(strm, Z_NO_FLUSH)) <> Z_STREAM_END do
+      begin
+        P := OutBuf;
+        Inc(OutBytes, BufInc);
+        ReallocMem(OutBuf, OutBytes);
+        strm.next_out := PChar(Integer(OutBuf) + (Integer(strm.next_out) - Integer(P)));
+        strm.avail_out := BufInc;
+      end;
+    finally
+      DCheck(inflateEnd(strm));
+    end;
+    ReallocMem(OutBuf, strm.total_out);
+    OutBytes := strm.total_out;
+  except
+    FreeMem(OutBuf);
+    raise
+  end;
+end;
+
+procedure DecompressToUserBuf(const InBuf: Pointer; InBytes: Integer;
+  const OutBuf: Pointer; BufSize: Integer);
+var
+  strm: TZStreamRec;
+begin
+  FillChar(strm, sizeof(strm), 0);
+  strm.zalloc := zlibAllocMem;
+  strm.zfree := zlibFreeMem;
+  strm.next_in := InBuf;
+  strm.avail_in := InBytes;
+  strm.next_out := OutBuf;
+  strm.avail_out := BufSize;
+  DCheck(inflateInit_(strm, zlib_version, sizeof(strm)));
+  try
+    if DCheck(inflate(strm, Z_FINISH)) <> Z_STREAM_END then
+      raise EZlibError.CreateRes(@sTargetBufferTooSmall);
+  finally
+    DCheck(inflateEnd(strm));
+  end;
+end;
+
+// TCustomZlibStream
+
+constructor TCustomZLibStream.Create(Strm: TStream);
+begin
+  inherited Create;
+  FStrm := Strm;
+  FStrmPos := Strm.Position;
+  FZRec.zalloc := zlibAllocMem;
+  FZRec.zfree := zlibFreeMem;
+end;
+
+procedure TCustomZLibStream.Progress(Sender: TObject);
+begin
+  if Assigned(FOnProgress) then FOnProgress(Sender);
+end;
+
+
+// TCompressionStream
+
+constructor TCompressionStream.Create(CompressionLevel: TCompressionLevel;
+  Dest: TStream);
+const
+  Levels: array [TCompressionLevel] of ShortInt =
+    (Z_NO_COMPRESSION, Z_BEST_SPEED, Z_DEFAULT_COMPRESSION, Z_BEST_COMPRESSION);
+begin
+  inherited Create(Dest);
+  FZRec.next_out := FBuffer;
+  FZRec.avail_out := sizeof(FBuffer);
+  CCheck(deflateInit_(FZRec, Levels[CompressionLevel], zlib_version, sizeof(FZRec)));
+end;
+
+destructor TCompressionStream.Destroy;
+begin
+  FZRec.next_in := nil;
+  FZRec.avail_in := 0;
+  try
+    if FStrm.Position <> FStrmPos then FStrm.Position := FStrmPos;
+    while (CCheck(deflate(FZRec, Z_FINISH)) <> Z_STREAM_END)
+      and (FZRec.avail_out = 0) do
+    begin
+      FStrm.WriteBuffer(FBuffer, sizeof(FBuffer));
+      FZRec.next_out := FBuffer;
+      FZRec.avail_out := sizeof(FBuffer);
+    end;
+    if FZRec.avail_out < sizeof(FBuffer) then
+      FStrm.WriteBuffer(FBuffer, sizeof(FBuffer) - FZRec.avail_out);
+  finally
+    deflateEnd(FZRec);
+  end;
+  inherited Destroy;
+end;
+
+function TCompressionStream.Read(var Buffer; Count: Longint): Longint;
+begin
+  raise ECompressionError.CreateRes(@sInvalidStreamOp);
+end;
+
+function TCompressionStream.Write(const Buffer; Count: Longint): Longint;
+begin
+  FZRec.next_in := @Buffer;
+  FZRec.avail_in := Count;
+  if FStrm.Position <> FStrmPos then FStrm.Position := FStrmPos;
+  while (FZRec.avail_in > 0) do
+  begin
+    CCheck(deflate(FZRec, 0));
+    if FZRec.avail_out = 0 then
+    begin
+      FStrm.WriteBuffer(FBuffer, sizeof(FBuffer));
+      FZRec.next_out := FBuffer;
+      FZRec.avail_out := sizeof(FBuffer);
+      FStrmPos := FStrm.Position;
+      Progress(Self);
+    end;
+  end;
+  Result := Count;
+end;
+
+function TCompressionStream.Seek(Offset: Longint; Origin: Word): Longint;
+begin
+  if (Offset = 0) and (Origin = soFromCurrent) then
+    Result := FZRec.total_in
+  else
+    raise ECompressionError.CreateRes(@sInvalidStreamOp);
+end;
+
+function TCompressionStream.GetCompressionRate: Single;
+begin
+  if FZRec.total_in = 0 then
+    Result := 0
+  else
+    Result := (1.0 - (FZRec.total_out / FZRec.total_in)) * 100.0;
+end;
+
+
+// TDecompressionStream
+
+constructor TDecompressionStream.Create(Source: TStream);
+begin
+  inherited Create(Source);
+  FZRec.next_in := FBuffer;
+  FZRec.avail_in := 0;
+  DCheck(inflateInit_(FZRec, zlib_version, sizeof(FZRec)));
+end;
+
+destructor TDecompressionStream.Destroy;
+begin
+  FStrm.Seek(-FZRec.avail_in, 1);
+  inflateEnd(FZRec);
+  inherited Destroy;
+end;
+
+function TDecompressionStream.Read(var Buffer; Count: Longint): Longint;
+begin
+  FZRec.next_out := @Buffer;
+  FZRec.avail_out := Count;
+  if FStrm.Position <> FStrmPos then FStrm.Position := FStrmPos;
+  while (FZRec.avail_out > 0) do
+  begin
+    if FZRec.avail_in = 0 then
+    begin
+      FZRec.avail_in := FStrm.Read(FBuffer, sizeof(FBuffer));
+      if FZRec.avail_in = 0 then
+      begin
+        Result := Count - FZRec.avail_out;
+        Exit;
+      end;
+      FZRec.next_in := FBuffer;
+      FStrmPos := FStrm.Position;
+      Progress(Self);
+    end;
+    CCheck(inflate(FZRec, 0));
+  end;
+  Result := Count;
+end;
+
+function TDecompressionStream.Write(const Buffer; Count: Longint): Longint;
+begin
+  raise EDecompressionError.CreateRes(@sInvalidStreamOp);
+end;
+
+function TDecompressionStream.Seek(Offset: Longint; Origin: Word): Longint;
+var
+  I: Integer;
+  Buf: array [0..4095] of Char;
+begin
+  if (Offset = 0) and (Origin = soFromBeginning) then
+  begin
+    DCheck(inflateReset(FZRec));
+    FZRec.next_in := FBuffer;
+    FZRec.avail_in := 0;
+    FStrm.Position := 0;
+    FStrmPos := 0;
+  end
+  else if ( (Offset >= 0) and (Origin = soFromCurrent)) or
+          ( ((Offset - FZRec.total_out) > 0) and (Origin = soFromBeginning)) then
+  begin
+    if Origin = soFromBeginning then Dec(Offset, FZRec.total_out);
+    if Offset > 0 then
+    begin
+      for I := 1 to Offset div sizeof(Buf) do
+        ReadBuffer(Buf, sizeof(Buf));
+      ReadBuffer(Buf, Offset mod sizeof(Buf));
+    end;
+  end
+  else
+    raise EDecompressionError.CreateRes(@sInvalidStreamOp);
+  Result := FZRec.total_out;
+end;
+
+
+end.
diff --git a/gs/zlib/contrib/delphi/ZLibConst.pas b/gs/zlib/contrib/delphi/ZLibConst.pas
new file mode 100644
index 000000000..cdfe13671
--- /dev/null
+++ b/gs/zlib/contrib/delphi/ZLibConst.pas
@@ -0,0 +1,11 @@
+unit ZLibConst;
+
+interface
+
+resourcestring
+  sTargetBufferTooSmall = 'ZLib error: target buffer may be too small';
+  sInvalidStreamOp = 'Invalid stream operation';
+
+implementation
+
+end.
diff --git a/gs/zlib/contrib/delphi/readme.txt b/gs/zlib/contrib/delphi/readme.txt
new file mode 100644
index 000000000..2dc9a8bba
--- /dev/null
+++ b/gs/zlib/contrib/delphi/readme.txt
@@ -0,0 +1,76 @@
+
+Overview
+========
+
+This directory contains an update to the ZLib interface unit,
+distributed by Borland as a Delphi supplemental component.
+
+The original ZLib unit is Copyright (c) 1997,99 Borland Corp.,
+and is based on zlib version 1.0.4.  There are a series of bugs
+and security problems associated with that old zlib version, and
+we recommend the users to update their ZLib unit.
+
+
+Summary of modifications
+========================
+
+- Improved makefile, adapted to zlib version 1.2.1.
+
+- Some field types from TZStreamRec are changed from Integer to
+  Longint, for consistency with the zlib.h header, and for 64-bit
+  readiness.
+
+- The zlib_version constant is updated.
+
+- The new Z_RLE strategy has its corresponding symbolic constant.
+
+- The allocation and deallocation functions and function types
+  (TAlloc, TFree, zlibAllocMem and zlibFreeMem) are now cdecl,
+  and _malloc and _free are added as C RTL stubs.  As a result,
+  the original C sources of zlib can be compiled out of the box,
+  and linked to the ZLib unit.
+
+
+Suggestions for improvements
+============================
+
+Currently, the ZLib unit provides only a limited wrapper around
+the zlib library, and much of the original zlib functionality is
+missing.  Handling compressed file formats like ZIP/GZIP or PNG
+cannot be implemented without having this functionality.
+Applications that handle these formats are either using their own,
+duplicated code, or not using the ZLib unit at all.
+
+Here are a few suggestions:
+
+- Checksum class wrappers around adler32() and crc32(), similar
+  to the Java classes that implement the java.util.zip.Checksum
+  interface.
+
+- The ability to read and write raw deflate streams, without the
+  zlib stream header and trailer.  Raw deflate streams are used
+  in the ZIP file format.
+
+- The ability to read and write gzip streams, used in the GZIP
+  file format, and normally produced by the gzip program.
+
+- The ability to select a different compression strategy, useful
+  to PNG and MNG image compression, and to multimedia compression
+  in general.  Besides the compression level
+
+    TCompressionLevel = (clNone, clFastest, clDefault, clMax);
+
+  which, in fact, could have used the 'z' prefix and avoided
+  TColor-like symbols
+
+    TCompressionLevel = (zcNone, zcFastest, zcDefault, zcMax);
+
+  there could be a compression strategy
+
+    TCompressionStrategy = (zsDefault, zsFiltered, zsHuffmanOnly, zsRle);
+
+- ZIP and GZIP stream handling via TStreams.
+
+
+--
+Cosmin Truta <cosmint@cs.ubbcluj.ro>
diff --git a/gs/zlib/contrib/delphi/zlibd32.mak b/gs/zlib/contrib/delphi/zlibd32.mak
new file mode 100644
index 000000000..88fafa0b1
--- /dev/null
+++ b/gs/zlib/contrib/delphi/zlibd32.mak
@@ -0,0 +1,93 @@
+# Makefile for zlib
+# For use with Delphi and C++ Builder under Win32
+# Updated for zlib 1.2.x by Cosmin Truta
+
+# ------------ Borland C++ ------------
+
+# This project uses the Delphi (fastcall/register) calling convention:
+LOC = -DZEXPORT=__fastcall -DZEXPORTVA=__cdecl
+
+CC = bcc32
+LD = bcc32
+AR = tlib
+# do not use "-pr" in CFLAGS
+CFLAGS = -a -d -k- -O2 $(LOC)
+LDFLAGS =
+
+
+# variables
+ZLIB_LIB = zlib.lib
+
+OBJ1 = adler32.obj compress.obj crc32.obj deflate.obj gzio.obj infback.obj
+OBJ2 = inffast.obj inflate.obj inftrees.obj trees.obj uncompr.obj zutil.obj
+OBJP1 = +adler32.obj+compress.obj+crc32.obj+deflate.obj+gzio.obj+infback.obj
+OBJP2 = +inffast.obj+inflate.obj+inftrees.obj+trees.obj+uncompr.obj+zutil.obj
+
+
+# targets
+all: $(ZLIB_LIB) example.exe minigzip.exe
+
+.c.obj:
+	$(CC) -c $(CFLAGS) $*.c
+
+adler32.obj: adler32.c zlib.h zconf.h
+
+compress.obj: compress.c zlib.h zconf.h
+
+crc32.obj: crc32.c zlib.h zconf.h crc32.h
+
+deflate.obj: deflate.c deflate.h zutil.h zlib.h zconf.h
+
+gzio.obj: gzio.c zutil.h zlib.h zconf.h
+
+infback.obj: infback.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inffast.obj: inffast.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h
+
+inflate.obj: inflate.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inftrees.obj: inftrees.c zutil.h zlib.h zconf.h inftrees.h
+
+trees.obj: trees.c zutil.h zlib.h zconf.h deflate.h trees.h
+
+uncompr.obj: uncompr.c zlib.h zconf.h
+
+zutil.obj: zutil.c zutil.h zlib.h zconf.h
+
+example.obj: example.c zlib.h zconf.h
+
+minigzip.obj: minigzip.c zlib.h zconf.h
+
+
+# For the sake of the old Borland make,
+# the command line is cut to fit in the MS-DOS 128 byte limit:
+$(ZLIB_LIB): $(OBJ1) $(OBJ2)
+	-del $(ZLIB_LIB)
+	$(AR) $(ZLIB_LIB) $(OBJP1)
+	$(AR) $(ZLIB_LIB) $(OBJP2)
+
+
+# testing
+test: example.exe minigzip.exe
+	example
+	echo hello world | minigzip | minigzip -d
+
+example.exe: example.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) example.obj $(ZLIB_LIB)
+
+minigzip.exe: minigzip.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) minigzip.obj $(ZLIB_LIB)
+
+
+# cleanup
+clean:
+	-del *.obj
+	-del *.exe
+	-del *.lib
+	-del *.tds
+	-del zlib.bak
+	-del foo.gz
+
diff --git a/gs/zlib/contrib/dotzlib/DotZLib.build b/gs/zlib/contrib/dotzlib/DotZLib.build
new file mode 100644
index 000000000..ed19cc9dc
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib.build
@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="utf-8" ?>

+<project name="DotZLib" default="build" basedir="./DotZLib">

+	<description>A .Net wrapper library around ZLib1.dll</description>

+

+	<property name="nunit.location" value="c:/program files/NUnit V2.1/bin" />

+	<property name="build.root" value="bin" />

+	

+	<property name="debug" value="true" />

+	<property name="nunit" value="true" />

+

+	<property name="build.folder" value="${build.root}/debug/" if="${debug}" />

+	<property name="build.folder" value="${build.root}/release/" unless="${debug}" />

+

+	<target name="clean" description="Remove all generated files">

+		<delete dir="${build.root}" failonerror="false" />

+	</target>

+

+	<target name="build" description="compiles the source code">

+		

+		<mkdir dir="${build.folder}" />

+		<csc target="library" output="${build.folder}DotZLib.dll" debug="${debug}">

+			<references basedir="${nunit.location}">

+				<includes if="${nunit}" name="nunit.framework.dll" />

+			</references>

+			<sources>

+				<includes name="*.cs" />

+				<excludes name="UnitTests.cs" unless="${nunit}" />

+			</sources>

+			<arg value="/d:nunit" if="${nunit}" />

+		</csc>

+	</target>

+

+</project>
\ No newline at end of file
diff --git a/gs/zlib/contrib/dotzlib/DotZLib.chm b/gs/zlib/contrib/dotzlib/DotZLib.chm
new file mode 100644
index 000000000..0bc7df76e
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib.chm
diff --git a/gs/zlib/contrib/dotzlib/DotZLib.sln b/gs/zlib/contrib/dotzlib/DotZLib.sln
new file mode 100644
index 000000000..ac45ca048
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib.sln
@@ -0,0 +1,21 @@
+Microsoft Visual Studio Solution File, Format Version 8.00

+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DotZLib", "DotZLib\DotZLib.csproj", "{BB1EE0B1-1808-46CB-B786-949D91117FC5}"

+	ProjectSection(ProjectDependencies) = postProject

+	EndProjectSection

+EndProject

+Global

+	GlobalSection(SolutionConfiguration) = preSolution

+		Debug = Debug

+		Release = Release

+	EndGlobalSection

+	GlobalSection(ProjectConfiguration) = postSolution

+		{BB1EE0B1-1808-46CB-B786-949D91117FC5}.Debug.ActiveCfg = Debug|.NET

+		{BB1EE0B1-1808-46CB-B786-949D91117FC5}.Debug.Build.0 = Debug|.NET

+		{BB1EE0B1-1808-46CB-B786-949D91117FC5}.Release.ActiveCfg = Release|.NET

+		{BB1EE0B1-1808-46CB-B786-949D91117FC5}.Release.Build.0 = Release|.NET

+	EndGlobalSection

+	GlobalSection(ExtensibilityGlobals) = postSolution

+	EndGlobalSection

+	GlobalSection(ExtensibilityAddIns) = postSolution

+	EndGlobalSection

+EndGlobal

diff --git a/gs/zlib/contrib/dotzlib/DotZLib/AssemblyInfo.cs b/gs/zlib/contrib/dotzlib/DotZLib/AssemblyInfo.cs
new file mode 100644
index 000000000..6fc0fdcc2
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib/AssemblyInfo.cs
@@ -0,0 +1,58 @@
+using System.Reflection;

+using System.Runtime.CompilerServices;

+

+//

+// General Information about an assembly is controlled through the following 

+// set of attributes. Change these attribute values to modify the information

+// associated with an assembly.

+//

+[assembly: AssemblyTitle("DotZLib")]

+[assembly: AssemblyDescription(".Net bindings for ZLib compression dll 1.2.x")]

+[assembly: AssemblyConfiguration("")]

+[assembly: AssemblyCompany("Henrik Ravn")]

+[assembly: AssemblyProduct("")]

+[assembly: AssemblyCopyright("(c) 2004 by Henrik Ravn")]

+[assembly: AssemblyTrademark("")]

+[assembly: AssemblyCulture("")]		

+

+//

+// Version information for an assembly consists of the following four values:

+//

+//      Major Version

+//      Minor Version 

+//      Build Number

+//      Revision

+//

+// You can specify all the values or you can default the Revision and Build Numbers 

+// by using the '*' as shown below:

+

+[assembly: AssemblyVersion("1.0.*")]

+

+//

+// In order to sign your assembly you must specify a key to use. Refer to the 

+// Microsoft .NET Framework documentation for more information on assembly signing.

+//

+// Use the attributes below to control which key is used for signing. 

+//

+// Notes: 

+//   (*) If no key is specified, the assembly is not signed.

+//   (*) KeyName refers to a key that has been installed in the Crypto Service

+//       Provider (CSP) on your machine. KeyFile refers to a file which contains

+//       a key.

+//   (*) If the KeyFile and the KeyName values are both specified, the 

+//       following processing occurs:

+//       (1) If the KeyName can be found in the CSP, that key is used.

+//       (2) If the KeyName does not exist and the KeyFile does exist, the key 

+//           in the KeyFile is installed into the CSP and used.

+//   (*) In order to create a KeyFile, you can use the sn.exe (Strong Name) utility.

+//       When specifying the KeyFile, the location of the KeyFile should be

+//       relative to the project output directory which is

+//       %Project Directory%\obj\<configuration>. For example, if your KeyFile is

+//       located in the project directory, you would specify the AssemblyKeyFile 

+//       attribute as [assembly: AssemblyKeyFile("..\\..\\mykey.snk")]

+//   (*) Delay Signing is an advanced option - see the Microsoft .NET Framework

+//       documentation for more information on this.

+//

+[assembly: AssemblyDelaySign(false)]

+[assembly: AssemblyKeyFile("")]

+[assembly: AssemblyKeyName("")]

diff --git a/gs/zlib/contrib/dotzlib/DotZLib/ChecksumImpl.cs b/gs/zlib/contrib/dotzlib/DotZLib/ChecksumImpl.cs
new file mode 100644
index 000000000..dfe7e90a8
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib/ChecksumImpl.cs
@@ -0,0 +1,202 @@
+//

+// © Copyright Henrik Ravn 2004

+//

+// Use, modification and distribution are subject to the Boost Software License, Version 1.0. 

+// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

+//

+

+using System;

+using System.Runtime.InteropServices;

+using System.Text;

+

+

+namespace DotZLib

+{

+    #region ChecksumGeneratorBase

+    /// <summary>

+    /// Implements the common functionality needed for all <see cref="ChecksumGenerator"/>s

+    /// </summary>

+    /// <example></example>

+    public abstract class ChecksumGeneratorBase : ChecksumGenerator

+    {

+        /// <summary>

+        /// The value of the current checksum

+        /// </summary>

+        protected uint _current;

+

+        /// <summary>

+        /// Initializes a new instance of the checksum generator base - the current checksum is 

+        /// set to zero

+        /// </summary>

+        public ChecksumGeneratorBase()

+        {

+            _current = 0;

+        }

+

+        /// <summary>

+        /// Initializes a new instance of the checksum generator basewith a specified value

+        /// </summary>

+        /// <param name="initialValue">The value to set the current checksum to</param>

+        public ChecksumGeneratorBase(uint initialValue)

+        {

+            _current = initialValue;

+        }

+

+        /// <summary>

+        /// Resets the current checksum to zero

+        /// </summary>

+        public void Reset() { _current = 0; }

+

+        /// <summary>

+        /// Gets the current checksum value

+        /// </summary>

+        public uint Value { get { return _current; } }

+

+        /// <summary>

+        /// Updates the current checksum with part of an array of bytes

+        /// </summary>

+        /// <param name="data">The data to update the checksum with</param>

+        /// <param name="offset">Where in <c>data</c> to start updating</param>

+        /// <param name="count">The number of bytes from <c>data</c> to use</param>

+        /// <exception cref="ArgumentException">The sum of offset and count is larger than the length of <c>data</c></exception>

+        /// <exception cref="NullReferenceException"><c>data</c> is a null reference</exception>

+        /// <exception cref="ArgumentOutOfRangeException">Offset or count is negative.</exception>

+        /// <remarks>All the other <c>Update</c> methods are implmeneted in terms of this one. 

+        /// This is therefore the only method a derived class has to implement</remarks>

+        public abstract void Update(byte[] data, int offset, int count);

+

+        /// <summary>

+        /// Updates the current checksum with an array of bytes.

+        /// </summary>

+        /// <param name="data">The data to update the checksum with</param>

+        public void Update(byte[] data)

+        {

+            Update(data, 0, data.Length);

+        }

+

+        /// <summary>

+        /// Updates the current checksum with the data from a string

+        /// </summary>

+        /// <param name="data">The string to update the checksum with</param>

+        /// <remarks>The characters in the string are converted by the UTF-8 encoding</remarks>

+        public void Update(string data)

+        {

+			Update(Encoding.UTF8.GetBytes(data));

+        }

+

+        /// <summary>

+        /// Updates the current checksum with the data from a string, using a specific encoding

+        /// </summary>

+        /// <param name="data">The string to update the checksum with</param>

+        /// <param name="encoding">The encoding to use</param>

+        public void Update(string data, Encoding encoding)

+        {

+            Update(encoding.GetBytes(data));

+        }

+

+    }

+    #endregion

+

+    #region CRC32

+    /// <summary>

+    /// Implements a CRC32 checksum generator

+    /// </summary>

+    public sealed class CRC32Checksum : ChecksumGeneratorBase    

+    {

+        #region DLL imports

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern uint crc32(uint crc, int data, uint length);

+

+        #endregion

+

+        /// <summary>

+        /// Initializes a new instance of the CRC32 checksum generator

+        /// </summary>

+        public CRC32Checksum() : base() {}

+

+        /// <summary>

+        /// Initializes a new instance of the CRC32 checksum generator with a specified value

+        /// </summary>

+        /// <param name="initialValue">The value to set the current checksum to</param>

+        public CRC32Checksum(uint initialValue) : base(initialValue) {}

+

+        /// <summary>

+        /// Updates the current checksum with part of an array of bytes

+        /// </summary>

+        /// <param name="data">The data to update the checksum with</param>

+        /// <param name="offset">Where in <c>data</c> to start updating</param>

+        /// <param name="count">The number of bytes from <c>data</c> to use</param>

+        /// <exception cref="ArgumentException">The sum of offset and count is larger than the length of <c>data</c></exception>

+        /// <exception cref="NullReferenceException"><c>data</c> is a null reference</exception>

+        /// <exception cref="ArgumentOutOfRangeException">Offset or count is negative.</exception>

+        public override void Update(byte[] data, int offset, int count)

+        {

+            if (offset < 0 || count < 0) throw new ArgumentOutOfRangeException();

+            if ((offset+count) > data.Length) throw new ArgumentException();

+            GCHandle hData = GCHandle.Alloc(data, GCHandleType.Pinned);

+            try

+            {

+                _current = crc32(_current, hData.AddrOfPinnedObject().ToInt32()+offset, (uint)count);

+            }

+            finally

+            {

+                hData.Free();

+            }

+        }

+

+    }

+    #endregion

+

+    #region Adler

+    /// <summary>

+    /// Implements a checksum generator that computes the Adler checksum on data

+    /// </summary>

+    public sealed class AdlerChecksum : ChecksumGeneratorBase    

+    {

+        #region DLL imports

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern uint adler32(uint adler, int data, uint length);

+

+        #endregion

+

+        /// <summary>

+        /// Initializes a new instance of the Adler checksum generator

+        /// </summary>

+        public AdlerChecksum() : base() {}

+

+        /// <summary>

+        /// Initializes a new instance of the Adler checksum generator with a specified value

+        /// </summary>

+        /// <param name="initialValue">The value to set the current checksum to</param>

+        public AdlerChecksum(uint initialValue) : base(initialValue) {}

+

+        /// <summary>

+        /// Updates the current checksum with part of an array of bytes

+        /// </summary>

+        /// <param name="data">The data to update the checksum with</param>

+        /// <param name="offset">Where in <c>data</c> to start updating</param>

+        /// <param name="count">The number of bytes from <c>data</c> to use</param>

+        /// <exception cref="ArgumentException">The sum of offset and count is larger than the length of <c>data</c></exception>

+        /// <exception cref="NullReferenceException"><c>data</c> is a null reference</exception>

+        /// <exception cref="ArgumentOutOfRangeException">Offset or count is negative.</exception>

+        public override void Update(byte[] data, int offset, int count)

+        {

+            if (offset < 0 || count < 0) throw new ArgumentOutOfRangeException();

+            if ((offset+count) > data.Length) throw new ArgumentException();

+            GCHandle hData = GCHandle.Alloc(data, GCHandleType.Pinned);

+            try

+            {

+                _current = adler32(_current, hData.AddrOfPinnedObject().ToInt32()+offset, (uint)count);

+            }

+            finally

+            {

+                hData.Free();

+            }

+        }

+

+    }

+    #endregion

+

+}
\ No newline at end of file
diff --git a/gs/zlib/contrib/dotzlib/DotZLib/CircularBuffer.cs b/gs/zlib/contrib/dotzlib/DotZLib/CircularBuffer.cs
new file mode 100644
index 000000000..16997e906
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib/CircularBuffer.cs
@@ -0,0 +1,83 @@
+//

+// © Copyright Henrik Ravn 2004

+//

+// Use, modification and distribution are subject to the Boost Software License, Version 1.0. 

+// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

+//

+

+using System;

+using System.Diagnostics;

+

+namespace DotZLib

+{

+

+	/// <summary>

+	/// This class implements a circular buffer

+	/// </summary>

+	internal class CircularBuffer

+	{

+        #region Private data

+        private int _capacity;

+        private int _head;

+        private int _tail;

+        private int _size;

+        private byte[] _buffer;

+        #endregion

+

+        public CircularBuffer(int capacity)

+        {    

+            Debug.Assert( capacity > 0 );

+            _buffer = new byte[capacity];

+            _capacity = capacity;

+            _head = 0;

+            _tail = 0;

+            _size = 0;

+        }

+

+        public int Size { get { return _size; } }

+

+        public int Put(byte[] source, int offset, int count)

+        {

+            Debug.Assert( count > 0 );

+            int trueCount = Math.Min(count, _capacity - Size);

+            for (int i = 0; i < trueCount; ++i)

+                _buffer[(_tail+i) % _capacity] = source[offset+i];

+            _tail += trueCount;

+            _tail %= _capacity;

+            _size += trueCount;

+            return trueCount;

+        }

+

+        public bool Put(byte b)

+        {

+            if (Size == _capacity) // no room

+                return false;

+            _buffer[_tail++] = b;

+            _tail %= _capacity;

+            ++_size;

+            return true;

+        }

+

+        public int Get(byte[] destination, int offset, int count)

+        {

+            int trueCount = Math.Min(count,Size);

+            for (int i = 0; i < trueCount; ++i)

+                destination[offset + i] = _buffer[(_head+i) % _capacity];

+            _head += trueCount;

+            _head %= _capacity;

+            _size -= trueCount;

+            return trueCount;

+        }

+

+        public int Get()

+        {

+            if (Size == 0)

+                return -1;

+

+            int result = (int)_buffer[_head++ % _capacity];

+            --_size;

+            return result;

+        }

+

+    }

+}

diff --git a/gs/zlib/contrib/dotzlib/DotZLib/CodecBase.cs b/gs/zlib/contrib/dotzlib/DotZLib/CodecBase.cs
new file mode 100644
index 000000000..954db7db0
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib/CodecBase.cs
@@ -0,0 +1,198 @@
+//

+// © Copyright Henrik Ravn 2004

+//

+// Use, modification and distribution are subject to the Boost Software License, Version 1.0. 

+// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

+//

+

+using System;

+using System.Runtime.InteropServices;

+

+namespace DotZLib

+{

+	/// <summary>

+	/// Implements the common functionality needed for all <see cref="Codec"/>s

+	/// </summary>

+	public abstract class CodecBase : Codec, IDisposable

+	{

+

+        #region Data members

+

+        /// <summary>

+        /// Instance of the internal zlib buffer structure that is 

+        /// passed to all functions in the zlib dll

+        /// </summary>

+        internal ZStream _ztream = new ZStream();

+

+        /// <summary>

+        /// True if the object instance has been disposed, false otherwise

+        /// </summary>

+        protected bool _isDisposed = false;

+

+        /// <summary>

+        /// The size of the internal buffers

+        /// </summary>

+        protected const int kBufferSize = 16384;

+

+        private byte[] _outBuffer = new byte[kBufferSize];

+        private byte[] _inBuffer = new byte[kBufferSize];

+

+        private GCHandle _hInput;

+        private GCHandle _hOutput;

+

+        private uint _checksum = 0;

+

+        #endregion

+

+        /// <summary>

+        /// Initializes a new instance of the <c>CodeBase</c> class. 

+        /// </summary>

+		public CodecBase()

+		{

+            try

+            {

+                _hInput = GCHandle.Alloc(_inBuffer, GCHandleType.Pinned);

+                _hOutput = GCHandle.Alloc(_outBuffer, GCHandleType.Pinned);

+            }

+            catch (Exception)

+            {

+                CleanUp(false);

+                throw;

+            }

+        }

+

+

+        #region Codec Members

+

+        /// <summary>

+        /// Occurs when more processed data are available.

+        /// </summary>

+        public event DataAvailableHandler DataAvailable;

+

+        /// <summary>

+        /// Fires the <see cref="DataAvailable"/> event

+        /// </summary>

+        protected void OnDataAvailable()

+        {

+            if (_ztream.total_out > 0)

+            {

+                if (DataAvailable != null)

+                    DataAvailable( _outBuffer, 0, (int)_ztream.total_out); 

+                resetOutput();

+            }

+        }

+

+        /// <summary>

+        /// Adds more data to the codec to be processed.

+        /// </summary>

+        /// <param name="data">Byte array containing the data to be added to the codec</param>

+        /// <remarks>Adding data may, or may not, raise the <c>DataAvailable</c> event</remarks>

+        public void Add(byte[] data)

+        {

+            Add(data,0,data.Length);

+        }

+

+        /// <summary>

+        /// Adds more data to the codec to be processed.

+        /// </summary>

+        /// <param name="data">Byte array containing the data to be added to the codec</param>

+        /// <param name="offset">The index of the first byte to add from <c>data</c></param>

+        /// <param name="count">The number of bytes to add</param>

+        /// <remarks>Adding data may, or may not, raise the <c>DataAvailable</c> event</remarks>

+        /// <remarks>This must be implemented by a derived class</remarks>

+        public abstract void Add(byte[] data, int offset, int count);

+

+        /// <summary>

+        /// Finishes up any pending data that needs to be processed and handled.

+        /// </summary>

+        /// <remarks>This must be implemented by a derived class</remarks>

+        public abstract void Finish();

+

+        /// <summary>

+        /// Gets the checksum of the data that has been added so far

+        /// </summary>

+        public uint Checksum { get { return _checksum; } }

+

+        #endregion

+

+        #region Destructor & IDisposable stuff

+

+        /// <summary>

+        /// Destroys this instance

+        /// </summary>

+        ~CodecBase()

+        {

+            CleanUp(false);

+        }

+

+        /// <summary>

+        /// Releases any unmanaged resources and calls the <see cref="CleanUp()"/> method of the derived class

+        /// </summary>

+        public void Dispose()

+        {

+            CleanUp(true);

+        }

+

+        /// <summary>

+        /// Performs any codec specific cleanup

+        /// </summary>

+        /// <remarks>This must be implemented by a derived class</remarks>

+        protected abstract void CleanUp();

+

+        // performs the release of the handles and calls the dereived CleanUp()

+        private void CleanUp(bool isDisposing)

+        {

+            if (!_isDisposed)

+            {

+                CleanUp();

+                if (_hInput.IsAllocated)

+                    _hInput.Free();

+                if (_hOutput.IsAllocated)

+                    _hOutput.Free();

+

+                _isDisposed = true;

+            }

+        }

+

+

+        #endregion

+

+        #region Helper methods

+

+        /// <summary>

+        /// Copies a number of bytes to the internal codec buffer - ready for proccesing

+        /// </summary>

+        /// <param name="data">The byte array that contains the data to copy</param>

+        /// <param name="startIndex">The index of the first byte to copy</param>

+        /// <param name="count">The number of bytes to copy from <c>data</c></param>

+        protected void copyInput(byte[] data, int startIndex, int count)

+        {

+            Array.Copy(data, startIndex, _inBuffer,0, count);

+            _ztream.next_in = _hInput.AddrOfPinnedObject();

+            _ztream.total_in = 0;

+            _ztream.avail_in = (uint)count;

+

+        }

+

+        /// <summary>

+        /// Resets the internal output buffers to a known state - ready for processing

+        /// </summary>

+        protected void resetOutput()

+        {

+            _ztream.total_out = 0;

+            _ztream.avail_out = kBufferSize;

+            _ztream.next_out = _hOutput.AddrOfPinnedObject();

+        }

+

+        /// <summary>

+        /// Updates the running checksum property

+        /// </summary>

+        /// <param name="newSum">The new checksum value</param>

+        protected void setChecksum(uint newSum)

+        {

+            _checksum = newSum;

+        }

+        #endregion

+

+    }

+}

diff --git a/gs/zlib/contrib/dotzlib/DotZLib/Deflater.cs b/gs/zlib/contrib/dotzlib/DotZLib/Deflater.cs
new file mode 100644
index 000000000..d7b8dccca
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib/Deflater.cs
@@ -0,0 +1,106 @@
+//

+// © Copyright Henrik Ravn 2004

+//

+// Use, modification and distribution are subject to the Boost Software License, Version 1.0. 

+// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

+//

+

+using System;

+using System.Diagnostics;

+using System.Runtime.InteropServices;

+

+namespace DotZLib

+{

+

+    /// <summary>

+    /// Implements a data compressor, using the deflate algorithm in the ZLib dll

+    /// </summary>

+	public sealed class Deflater : CodecBase

+	{

+        #region Dll imports

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl, CharSet=CharSet.Ansi)]

+        private static extern int deflateInit_(ref ZStream sz, int level, string vs, int size);

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern int deflate(ref ZStream sz, int flush);

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern int deflateReset(ref ZStream sz);

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern int deflateEnd(ref ZStream sz);

+        #endregion

+

+        /// <summary>

+        /// Constructs an new instance of the <c>Deflater</c>

+        /// </summary>

+        /// <param name="level">The compression level to use for this <c>Deflater</c></param>

+		public Deflater(CompressLevel level) : base()

+		{

+            int retval = deflateInit_(ref _ztream, (int)level, Info.Version, Marshal.SizeOf(_ztream));

+            if (retval != 0)

+                throw new ZLibException(retval, "Could not initialize deflater");

+

+            resetOutput();

+		}

+

+        /// <summary>

+        /// Adds more data to the codec to be processed.

+        /// </summary>

+        /// <param name="data">Byte array containing the data to be added to the codec</param>

+        /// <param name="offset">The index of the first byte to add from <c>data</c></param>

+        /// <param name="count">The number of bytes to add</param>

+        /// <remarks>Adding data may, or may not, raise the <c>DataAvailable</c> event</remarks>

+        public override void Add(byte[] data, int offset, int count)

+        {

+            if (data == null) throw new ArgumentNullException();

+            if (offset < 0 || count < 0) throw new ArgumentOutOfRangeException();

+            if ((offset+count) > data.Length) throw new ArgumentException();

+            

+            int total = count;

+            int inputIndex = offset;

+            int err = 0;

+

+            while (err >= 0 && inputIndex < total)

+            {

+                copyInput(data, inputIndex, Math.Min(total - inputIndex, kBufferSize));

+                while (err >= 0 && _ztream.avail_in > 0)

+                {

+                    err = deflate(ref _ztream, (int)FlushTypes.None);

+                    if (err == 0)

+                        while (_ztream.avail_out == 0)

+                        {

+                            OnDataAvailable();

+                            err = deflate(ref _ztream, (int)FlushTypes.None);

+                        }

+                    inputIndex += (int)_ztream.total_in;

+                }

+            }

+            setChecksum( _ztream.adler );

+        }

+

+

+        /// <summary>

+        /// Finishes up any pending data that needs to be processed and handled.

+        /// </summary>

+        public override void Finish()

+        {

+            int err;

+            do 

+            {

+                err = deflate(ref _ztream, (int)FlushTypes.Finish);

+                OnDataAvailable();

+            }

+            while (err == 0);

+            setChecksum( _ztream.adler );

+            deflateReset(ref _ztream);

+            resetOutput();

+        }

+

+        /// <summary>

+        /// Closes the internal zlib deflate stream

+        /// </summary>

+        protected override void CleanUp() { deflateEnd(ref _ztream); }

+

+    }

+}

diff --git a/gs/zlib/contrib/dotzlib/DotZLib/DotZLib.cs b/gs/zlib/contrib/dotzlib/DotZLib/DotZLib.cs
new file mode 100644
index 000000000..410deb088
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib/DotZLib.cs
@@ -0,0 +1,288 @@
+//

+// © Copyright Henrik Ravn 2004

+//

+// Use, modification and distribution are subject to the Boost Software License, Version 1.0. 

+// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

+//

+

+using System;

+using System.IO;

+using System.Runtime.InteropServices;

+using System.Text;

+

+

+namespace DotZLib

+{

+

+    #region Internal types

+

+    /// <summary>

+    /// Defines constants for the various flush types used with zlib

+    /// </summary>

+    internal enum FlushTypes 

+    {

+        None,  Partial,  Sync,  Full,  Finish,  Block

+    }

+

+    #region ZStream structure

+    // internal mapping of the zlib zstream structure for marshalling

+    [StructLayoutAttribute(LayoutKind.Sequential, Pack=4, Size=0, CharSet=CharSet.Ansi)]

+    internal struct ZStream

+    {

+        public IntPtr next_in;

+        public uint avail_in;

+        public uint total_in;

+

+        public IntPtr next_out;

+        public uint avail_out;

+        public uint total_out;

+

+        [MarshalAs(UnmanagedType.LPStr)]

+        string msg; 

+        uint state;

+

+        uint zalloc;

+        uint zfree;

+        uint opaque;

+

+        int data_type;

+        public uint adler;

+        uint reserved;

+    }

+

+    #endregion

+    

+    #endregion

+

+    #region Public enums

+    /// <summary>

+    /// Defines constants for the available compression levels in zlib

+    /// </summary>

+    public enum CompressLevel : int

+    {

+        /// <summary>

+        /// The default compression level with a reasonable compromise between compression and speed

+        /// </summary>

+        Default = -1,   

+        /// <summary>

+        /// No compression at all. The data are passed straight through.

+        /// </summary>

+        None = 0,

+        /// <summary>

+        /// The maximum compression rate available.

+        /// </summary>

+        Best = 9,   

+        /// <summary>

+        /// The fastest available compression level.

+        /// </summary>

+        Fastest = 1

+    }

+    #endregion

+

+    #region Exception classes

+    /// <summary>

+    /// The exception that is thrown when an error occurs on the zlib dll

+    /// </summary>

+    public class ZLibException : ApplicationException

+    {

+        /// <summary>

+        /// Initializes a new instance of the <see cref="ZLibException"/> class with a specified 

+        /// error message and error code

+        /// </summary>

+        /// <param name="errorCode">The zlib error code that caused the exception</param>

+        /// <param name="msg">A message that (hopefully) describes the error</param>

+        public ZLibException(int errorCode, string msg) : base(String.Format("ZLib error {0} {1}", errorCode, msg))

+        {

+        }

+

+        /// <summary>

+        /// Initializes a new instance of the <see cref="ZLibException"/> class with a specified 

+        /// error code

+        /// </summary>

+        /// <param name="errorCode">The zlib error code that caused the exception</param>

+        public ZLibException(int errorCode) : base(String.Format("ZLib error {0}", errorCode))

+        {

+        }

+    }

+    #endregion

+

+    #region Interfaces

+

+    /// <summary>

+    /// Declares methods and properties that enables a running checksum to be calculated 

+    /// </summary>

+    public interface ChecksumGenerator

+    {

+        /// <summary>

+        /// Gets the current value of the checksum

+        /// </summary>

+        uint Value { get; }

+

+        /// <summary>

+        /// Clears the current checksum to 0

+        /// </summary>

+        void Reset();

+

+        /// <summary>

+        /// Updates the current checksum with an array of bytes

+        /// </summary>

+        /// <param name="data">The data to update the checksum with</param>

+        void Update(byte[] data);

+

+        /// <summary>

+        /// Updates the current checksum with part of an array of bytes

+        /// </summary>

+        /// <param name="data">The data to update the checksum with</param>

+        /// <param name="offset">Where in <c>data</c> to start updating</param>

+        /// <param name="count">The number of bytes from <c>data</c> to use</param>

+        /// <exception cref="ArgumentException">The sum of offset and count is larger than the length of <c>data</c></exception>

+        /// <exception cref="ArgumentNullException"><c>data</c> is a null reference</exception>

+        /// <exception cref="ArgumentOutOfRangeException">Offset or count is negative.</exception>

+        void Update(byte[] data, int offset, int count);

+

+        /// <summary>

+        /// Updates the current checksum with the data from a string

+        /// </summary>

+        /// <param name="data">The string to update the checksum with</param>

+        /// <remarks>The characters in the string are converted by the UTF-8 encoding</remarks>

+        void Update(string data);

+

+        /// <summary>

+        /// Updates the current checksum with the data from a string, using a specific encoding

+        /// </summary>

+        /// <param name="data">The string to update the checksum with</param>

+        /// <param name="encoding">The encoding to use</param>

+        void Update(string data, Encoding encoding);

+    }

+

+

+    /// <summary>

+    /// Represents the method that will be called from a codec when new data

+    /// are available.

+    /// </summary>

+    /// <paramref name="data">The byte array containing the processed data</paramref>

+    /// <paramref name="startIndex">The index of the first processed byte in <c>data</c></paramref>

+    /// <paramref name="count">The number of processed bytes available</paramref>

+    /// <remarks>On return from this method, the data may be overwritten, so grab it while you can. 

+    /// You cannot assume that startIndex will be zero.

+    /// </remarks>

+    public delegate void DataAvailableHandler(byte[] data, int startIndex, int count);

+

+    /// <summary>

+    /// Declares methods and events for implementing compressors/decompressors

+    /// </summary>

+    public interface Codec

+    {

+        /// <summary>

+        /// Occurs when more processed data are available.

+        /// </summary>

+        event DataAvailableHandler DataAvailable;

+

+        /// <summary>

+        /// Adds more data to the codec to be processed.

+        /// </summary>

+        /// <param name="data">Byte array containing the data to be added to the codec</param>

+        /// <remarks>Adding data may, or may not, raise the <c>DataAvailable</c> event</remarks>

+        void Add(byte[] data);

+

+        /// <summary>

+        /// Adds more data to the codec to be processed.

+        /// </summary>

+        /// <param name="data">Byte array containing the data to be added to the codec</param>

+        /// <param name="offset">The index of the first byte to add from <c>data</c></param>

+        /// <param name="count">The number of bytes to add</param>

+        /// <remarks>Adding data may, or may not, raise the <c>DataAvailable</c> event</remarks>

+        void Add(byte[] data, int offset, int count);

+

+        /// <summary>

+        /// Finishes up any pending data that needs to be processed and handled.

+        /// </summary>

+        void Finish();

+

+        /// <summary>

+        /// Gets the checksum of the data that has been added so far

+        /// </summary>

+        uint Checksum { get; }

+

+

+    }

+

+    #endregion

+

+    #region Classes

+    /// <summary>

+    /// Encapsulates general information about the ZLib library

+    /// </summary>

+    public class Info

+    {

+        #region DLL imports

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern uint zlibCompileFlags();

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern string zlibVersion();

+        #endregion

+

+        #region Private stuff

+        private uint _flags;

+

+        // helper function that unpacks a bitsize mask

+        private static int bitSize(uint bits)

+        {

+            switch (bits)

+            {

+                case 0: return 16;

+                case 1: return 32;

+                case 2: return 64;

+            }

+            return -1;

+        }

+        #endregion

+

+        /// <summary>

+        /// Constructs an instance of the <c>Info</c> class.

+        /// </summary>

+        public Info()

+        {

+            _flags = zlibCompileFlags();

+        }

+

+        /// <summary>

+        /// True if the library is compiled with debug info

+        /// </summary>

+        public bool HasDebugInfo { get { return 0 != (_flags & 0x100); } }

+

+        /// <summary>

+        /// True if the library is compiled with assembly optimizations

+        /// </summary>

+        public bool UsesAssemblyCode { get { return 0 != (_flags & 0x200); } }

+

+        /// <summary>

+        /// Gets the size of the unsigned int that was compiled into Zlib

+        /// </summary>

+        public int SizeOfUInt { get { return bitSize(_flags & 3); } }

+

+        /// <summary>

+        /// Gets the size of the unsigned long that was compiled into Zlib

+        /// </summary>

+        public int SizeOfULong { get { return bitSize((_flags >> 2) & 3); } }

+

+        /// <summary>

+        /// Gets the size of the pointers that were compiled into Zlib

+        /// </summary>

+        public int SizeOfPointer { get { return bitSize((_flags >> 4) & 3); } }

+

+        /// <summary>

+        /// Gets the size of the z_off_t type that was compiled into Zlib

+        /// </summary>

+        public int SizeOfOffset { get { return bitSize((_flags >> 6) & 3); } }

+

+        /// <summary>

+        /// Gets the version of ZLib as a string, e.g. "1.2.1"

+        /// </summary>

+        public static string Version { get { return zlibVersion(); } }

+    }

+

+    #endregion

+

+}

diff --git a/gs/zlib/contrib/dotzlib/DotZLib/DotZLib.csproj b/gs/zlib/contrib/dotzlib/DotZLib/DotZLib.csproj
new file mode 100644
index 000000000..71eeb8590
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib/DotZLib.csproj
@@ -0,0 +1,141 @@
+<VisualStudioProject>

+    <CSHARP

+        ProjectType = "Local"

+        ProductVersion = "7.10.3077"

+        SchemaVersion = "2.0"

+        ProjectGuid = "{BB1EE0B1-1808-46CB-B786-949D91117FC5}"

+    >

+        <Build>

+            <Settings

+                ApplicationIcon = ""

+                AssemblyKeyContainerName = ""

+                AssemblyName = "DotZLib"

+                AssemblyOriginatorKeyFile = ""

+                DefaultClientScript = "JScript"

+                DefaultHTMLPageLayout = "Grid"

+                DefaultTargetSchema = "IE50"

+                DelaySign = "false"

+                OutputType = "Library"

+                PreBuildEvent = ""

+                PostBuildEvent = ""

+                RootNamespace = "DotZLib"

+                RunPostBuildEvent = "OnBuildSuccess"

+                StartupObject = ""

+            >

+                <Config

+                    Name = "Debug"

+                    AllowUnsafeBlocks = "false"

+                    BaseAddress = "285212672"

+                    CheckForOverflowUnderflow = "false"

+                    ConfigurationOverrideFile = ""

+                    DefineConstants = "DEBUG;TRACE"

+                    DocumentationFile = "docs\DotZLib.xml"

+                    DebugSymbols = "true"

+                    FileAlignment = "4096"

+                    IncrementalBuild = "false"

+                    NoStdLib = "false"

+                    NoWarn = "1591"

+                    Optimize = "false"

+                    OutputPath = "bin\Debug\"

+                    RegisterForComInterop = "false"

+                    RemoveIntegerChecks = "false"

+                    TreatWarningsAsErrors = "false"

+                    WarningLevel = "4"

+                />

+                <Config

+                    Name = "Release"

+                    AllowUnsafeBlocks = "false"

+                    BaseAddress = "285212672"

+                    CheckForOverflowUnderflow = "false"

+                    ConfigurationOverrideFile = ""

+                    DefineConstants = "TRACE"

+                    DocumentationFile = "docs\DotZLib.xml"

+                    DebugSymbols = "false"

+                    FileAlignment = "4096"

+                    IncrementalBuild = "false"

+                    NoStdLib = "false"

+                    NoWarn = ""

+                    Optimize = "true"

+                    OutputPath = "bin\Release\"

+                    RegisterForComInterop = "false"

+                    RemoveIntegerChecks = "false"

+                    TreatWarningsAsErrors = "false"

+                    WarningLevel = "4"

+                />

+            </Settings>

+            <References>

+                <Reference

+                    Name = "System"

+                    AssemblyName = "System"

+                    HintPath = "C:\WINNT\Microsoft.NET\Framework\v1.1.4322\System.dll"

+                />

+                <Reference

+                    Name = "System.Data"

+                    AssemblyName = "System.Data"

+                    HintPath = "C:\WINNT\Microsoft.NET\Framework\v1.1.4322\System.Data.dll"

+                />

+                <Reference

+                    Name = "System.XML"

+                    AssemblyName = "System.Xml"

+                    HintPath = "C:\WINNT\Microsoft.NET\Framework\v1.1.4322\System.XML.dll"

+                />

+                <Reference

+                    Name = "nunit.framework"

+                    AssemblyName = "nunit.framework"

+                    HintPath = "E:\apps\NUnit V2.1\\bin\nunit.framework.dll"

+                    AssemblyFolderKey = "hklm\dn\nunit.framework"

+                />

+            </References>

+        </Build>

+        <Files>

+            <Include>

+                <File

+                    RelPath = "AssemblyInfo.cs"

+                    SubType = "Code"

+                    BuildAction = "Compile"

+                />

+                <File

+                    RelPath = "ChecksumImpl.cs"

+                    SubType = "Code"

+                    BuildAction = "Compile"

+                />

+                <File

+                    RelPath = "CircularBuffer.cs"

+                    SubType = "Code"

+                    BuildAction = "Compile"

+                />

+                <File

+                    RelPath = "CodecBase.cs"

+                    SubType = "Code"

+                    BuildAction = "Compile"

+                />

+                <File

+                    RelPath = "Deflater.cs"

+                    SubType = "Code"

+                    BuildAction = "Compile"

+                />

+                <File

+                    RelPath = "DotZLib.cs"

+                    SubType = "Code"

+                    BuildAction = "Compile"

+                />

+                <File

+                    RelPath = "GZipStream.cs"

+                    SubType = "Code"

+                    BuildAction = "Compile"

+                />

+                <File

+                    RelPath = "Inflater.cs"

+                    SubType = "Code"

+                    BuildAction = "Compile"

+                />

+                <File

+                    RelPath = "UnitTests.cs"

+                    SubType = "Code"

+                    BuildAction = "Compile"

+                />

+            </Include>

+        </Files>

+    </CSHARP>

+</VisualStudioProject>

+

diff --git a/gs/zlib/contrib/dotzlib/DotZLib/GZipStream.cs b/gs/zlib/contrib/dotzlib/DotZLib/GZipStream.cs
new file mode 100644
index 000000000..f861675b5
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib/GZipStream.cs
@@ -0,0 +1,301 @@
+//

+// © Copyright Henrik Ravn 2004

+//

+// Use, modification and distribution are subject to the Boost Software License, Version 1.0. 

+// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

+//

+

+using System;

+using System.IO;

+using System.Runtime.InteropServices;

+

+namespace DotZLib

+{

+	/// <summary>

+	/// Implements a compressed <see cref="Stream"/>, in GZip (.gz) format.

+	/// </summary>

+	public class GZipStream : Stream, IDisposable

+	{

+        #region Dll Imports

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl, CharSet=CharSet.Ansi)]

+        private static extern IntPtr gzopen(string name, string mode);

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern int gzclose(IntPtr gzFile);

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern int gzwrite(IntPtr gzFile, int data, int length);

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern int gzread(IntPtr gzFile, int data, int length);

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern int gzgetc(IntPtr gzFile);

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern int gzputc(IntPtr gzFile, int c);

+

+        #endregion

+

+        #region Private data

+        private IntPtr _gzFile;

+        private bool _isDisposed = false;

+        private bool _isWriting;

+        #endregion

+

+        #region Constructors

+        /// <summary>

+        /// Creates a new file as a writeable GZipStream

+        /// </summary>

+        /// <param name="fileName">The name of the compressed file to create</param>

+        /// <param name="level">The compression level to use when adding data</param>

+        /// <exception cref="ZLibException">If an error occurred in the internal zlib function</exception>

+		public GZipStream(string fileName, CompressLevel level)

+		{

+            _isWriting = true;

+            _gzFile = gzopen(fileName, String.Format("wb{0}", (int)level));

+            if (_gzFile == IntPtr.Zero)

+                throw new ZLibException(-1, "Could not open " + fileName);

+		}

+

+        /// <summary>

+        /// Opens an existing file as a readable GZipStream

+        /// </summary>

+        /// <param name="fileName">The name of the file to open</param>

+        /// <exception cref="ZLibException">If an error occurred in the internal zlib function</exception>

+        public GZipStream(string fileName)

+        {

+            _isWriting = false;

+            _gzFile = gzopen(fileName, "rb");

+            if (_gzFile == IntPtr.Zero)

+                throw new ZLibException(-1, "Could not open " + fileName);

+

+        }

+        #endregion

+

+        #region Access properties

+        /// <summary>

+        /// Returns true of this stream can be read from, false otherwise

+        /// </summary>

+        public override bool CanRead

+        {

+            get

+            {

+                return !_isWriting;

+            }

+        }

+    

+

+        /// <summary>

+        /// Returns false.

+        /// </summary>

+        public override bool CanSeek

+        {

+            get

+            {

+                return false;

+            }

+        }

+    

+        /// <summary>

+        /// Returns true if this tsream is writeable, false otherwise

+        /// </summary>

+        public override bool CanWrite

+        {

+            get

+            {

+                return _isWriting;

+            }

+        }

+        #endregion

+    

+        #region Destructor & IDispose stuff

+

+        /// <summary>

+        /// Destroys this instance

+        /// </summary>

+        ~GZipStream()

+        {

+            cleanUp(false);

+        }

+

+        /// <summary>

+        /// Closes the external file handle

+        /// </summary>

+        public void Dispose()

+        {

+            cleanUp(true);

+        }

+

+        // Does the actual closing of the file handle.

+        private void cleanUp(bool isDisposing)

+        {

+            if (!_isDisposed)

+            {

+                gzclose(_gzFile);

+                _isDisposed = true;

+            }

+        }

+        #endregion

+    

+        #region Basic reading and writing

+        /// <summary>

+        /// Attempts to read a number of bytes from the stream.

+        /// </summary>

+        /// <param name="buffer">The destination data buffer</param>

+        /// <param name="offset">The index of the first destination byte in <c>buffer</c></param>

+        /// <param name="count">The number of bytes requested</param>

+        /// <returns>The number of bytes read</returns>

+        /// <exception cref="ArgumentNullException">If <c>buffer</c> is null</exception>

+        /// <exception cref="ArgumentOutOfRangeException">If <c>count</c> or <c>offset</c> are negative</exception>

+        /// <exception cref="ArgumentException">If <c>offset</c>  + <c>count</c> is &gt; buffer.Length</exception>

+        /// <exception cref="NotSupportedException">If this stream is not readable.</exception>

+        /// <exception cref="ObjectDisposedException">If this stream has been disposed.</exception>

+        public override int Read(byte[] buffer, int offset, int count)

+        {

+            if (!CanRead) throw new NotSupportedException();

+            if (buffer == null) throw new ArgumentNullException();

+            if (offset < 0 || count < 0) throw new ArgumentOutOfRangeException();

+            if ((offset+count) > buffer.Length) throw new ArgumentException();

+            if (_isDisposed) throw new ObjectDisposedException("GZipStream");

+

+            GCHandle h = GCHandle.Alloc(buffer, GCHandleType.Pinned);

+            int result;

+            try

+            {

+                result = gzread(_gzFile, h.AddrOfPinnedObject().ToInt32() + offset, count);

+                if (result < 0)

+                    throw new IOException();

+            }

+            finally

+            {

+                h.Free();

+            }

+            return result;

+        }

+

+        /// <summary>

+        /// Attempts to read a single byte from the stream.

+        /// </summary>

+        /// <returns>The byte that was read, or -1 in case of error or End-Of-File</returns>

+        public override int ReadByte()

+        {

+            if (!CanRead) throw new NotSupportedException();

+            if (_isDisposed) throw new ObjectDisposedException("GZipStream");

+            return gzgetc(_gzFile);

+        }

+

+        /// <summary>

+        /// Writes a number of bytes to the stream

+        /// </summary>

+        /// <param name="buffer"></param>

+        /// <param name="offset"></param>

+        /// <param name="count"></param>

+        /// <exception cref="ArgumentNullException">If <c>buffer</c> is null</exception>

+        /// <exception cref="ArgumentOutOfRangeException">If <c>count</c> or <c>offset</c> are negative</exception>

+        /// <exception cref="ArgumentException">If <c>offset</c>  + <c>count</c> is &gt; buffer.Length</exception>

+        /// <exception cref="NotSupportedException">If this stream is not writeable.</exception>

+        /// <exception cref="ObjectDisposedException">If this stream has been disposed.</exception>

+        public override void Write(byte[] buffer, int offset, int count)

+        {

+            if (!CanWrite) throw new NotSupportedException();

+            if (buffer == null) throw new ArgumentNullException();

+            if (offset < 0 || count < 0) throw new ArgumentOutOfRangeException();

+            if ((offset+count) > buffer.Length) throw new ArgumentException();

+            if (_isDisposed) throw new ObjectDisposedException("GZipStream");

+

+            GCHandle h = GCHandle.Alloc(buffer, GCHandleType.Pinned);

+            try

+            {

+                int result = gzwrite(_gzFile, h.AddrOfPinnedObject().ToInt32() + offset, count);

+                if (result < 0)

+                    throw new IOException();

+            }

+            finally

+            {

+                h.Free();

+            }

+        }

+

+        /// <summary>

+        /// Writes a single byte to the stream

+        /// </summary>

+        /// <param name="value">The byte to add to the stream.</param>

+        /// <exception cref="NotSupportedException">If this stream is not writeable.</exception>

+        /// <exception cref="ObjectDisposedException">If this stream has been disposed.</exception>

+        public override void WriteByte(byte value)

+        {

+            if (!CanWrite) throw new NotSupportedException();

+            if (_isDisposed) throw new ObjectDisposedException("GZipStream");

+

+            int result = gzputc(_gzFile, (int)value);

+            if (result < 0)

+                throw new IOException();

+        }

+        #endregion

+

+        #region Position & length stuff

+        /// <summary>

+        /// Not supported.

+        /// </summary>

+        /// <param name="value"></param>

+        /// <exception cref="NotSupportedException">Always thrown</exception>

+        public override void SetLength(long value)

+        {

+            throw new NotSupportedException();

+        }

+    

+        /// <summary>

+        ///  Not suppported.

+        /// </summary>

+        /// <param name="offset"></param>

+        /// <param name="origin"></param>

+        /// <returns></returns>

+        /// <exception cref="NotSupportedException">Always thrown</exception>

+        public override long Seek(long offset, SeekOrigin origin)

+        {

+            throw new NotSupportedException();

+        }

+    

+        /// <summary>

+        /// Flushes the <c>GZipStream</c>.

+        /// </summary>

+        /// <remarks>In this implementation, this method does nothing. This is because excessive

+        /// flushing may degrade the achievable compression rates.</remarks>

+        public override void Flush()

+        {

+            // left empty on purpose

+        }

+    

+        /// <summary>

+        /// Gets/sets the current position in the <c>GZipStream</c>. Not suppported.

+        /// </summary>

+        /// <remarks>In this implementation this property is not supported</remarks>

+        /// <exception cref="NotSupportedException">Always thrown</exception>

+        public override long Position

+        {

+            get

+            {

+                throw new NotSupportedException();

+            }

+            set

+            {

+                throw new NotSupportedException();

+            }

+        }

+    

+        /// <summary>

+        /// Gets the size of the stream. Not suppported.

+        /// </summary>

+        /// <remarks>In this implementation this property is not supported</remarks>

+        /// <exception cref="NotSupportedException">Always thrown</exception>

+        public override long Length

+        {

+            get

+            {

+                throw new NotSupportedException();

+            }

+        }

+        #endregion

+    }

+}

diff --git a/gs/zlib/contrib/dotzlib/DotZLib/Inflater.cs b/gs/zlib/contrib/dotzlib/DotZLib/Inflater.cs
new file mode 100644
index 000000000..4e60cda07
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib/Inflater.cs
@@ -0,0 +1,105 @@
+//

+// © Copyright Henrik Ravn 2004

+//

+// Use, modification and distribution are subject to the Boost Software License, Version 1.0. 

+// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

+//

+

+using System;

+using System.Diagnostics;

+using System.Runtime.InteropServices;

+

+namespace DotZLib

+{

+    

+    /// <summary>

+    /// Implements a data decompressor, using the inflate algorithm in the ZLib dll

+    /// </summary>

+    public class Inflater : CodecBase

+	{

+        #region Dll imports

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl, CharSet=CharSet.Ansi)]

+        private static extern int inflateInit_(ref ZStream sz, string vs, int size);

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern int inflate(ref ZStream sz, int flush);

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern int inflateReset(ref ZStream sz);

+

+        [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]

+        private static extern int inflateEnd(ref ZStream sz);

+        #endregion

+

+        /// <summary>

+        /// Constructs an new instance of the <c>Inflater</c>

+        /// </summary>

+        public Inflater() : base()

+		{

+            int retval = inflateInit_(ref _ztream, Info.Version, Marshal.SizeOf(_ztream));

+            if (retval != 0)

+                throw new ZLibException(retval, "Could not initialize inflater");

+

+            resetOutput();

+        }

+

+

+        /// <summary>

+        /// Adds more data to the codec to be processed.

+        /// </summary>

+        /// <param name="data">Byte array containing the data to be added to the codec</param>

+        /// <param name="offset">The index of the first byte to add from <c>data</c></param>

+        /// <param name="count">The number of bytes to add</param>

+        /// <remarks>Adding data may, or may not, raise the <c>DataAvailable</c> event</remarks>

+        public override void Add(byte[] data, int offset, int count)

+        {

+            if (data == null) throw new ArgumentNullException();

+            if (offset < 0 || count < 0) throw new ArgumentOutOfRangeException();

+            if ((offset+count) > data.Length) throw new ArgumentException();

+

+            int total = count;

+            int inputIndex = offset;

+            int err = 0;

+

+            while (err >= 0 && inputIndex < total)

+            {

+                copyInput(data, inputIndex, Math.Min(total - inputIndex, kBufferSize));

+                err = inflate(ref _ztream, (int)FlushTypes.None);

+                if (err == 0)

+                    while (_ztream.avail_out == 0)

+                    {

+                        OnDataAvailable();

+                        err = inflate(ref _ztream, (int)FlushTypes.None);

+                    }

+

+                inputIndex += (int)_ztream.total_in;

+            }

+            setChecksum( _ztream.adler );

+        }

+

+

+        /// <summary>

+        /// Finishes up any pending data that needs to be processed and handled.

+        /// </summary>

+        public override void Finish()

+        {

+            int err;

+            do 

+            {

+                err = inflate(ref _ztream, (int)FlushTypes.Finish);

+                OnDataAvailable();

+            }

+            while (err == 0);

+            setChecksum( _ztream.adler );

+            inflateReset(ref _ztream);

+            resetOutput();

+        }

+

+        /// <summary>

+        /// Closes the internal zlib inflate stream

+        /// </summary>

+        protected override void CleanUp() { inflateEnd(ref _ztream); }

+

+

+	}

+}

diff --git a/gs/zlib/contrib/dotzlib/DotZLib/UnitTests.cs b/gs/zlib/contrib/dotzlib/DotZLib/UnitTests.cs
new file mode 100644
index 000000000..8dc00db92
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/DotZLib/UnitTests.cs
@@ -0,0 +1,274 @@
+//

+// © Copyright Henrik Ravn 2004

+//

+// Use, modification and distribution are subject to the Boost Software License, Version 1.0. 

+// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

+//

+

+using System;

+using System.Collections;

+using System.IO;

+

+// uncomment the define below to include unit tests

+//#define nunit

+#if nunit

+using NUnit.Framework;

+

+// Unit tests for the DotZLib class library

+// ----------------------------------------

+//

+// Use this with NUnit 2 from http://www.nunit.org

+//

+

+namespace DotZLibTests

+{

+    using DotZLib;

+

+    // helper methods

+    internal class Utils

+    {

+        public static bool byteArrEqual( byte[] lhs, byte[] rhs )

+        {

+            if (lhs.Length != rhs.Length)

+                return false;

+            for (int i = lhs.Length-1; i >= 0; --i)

+                if (lhs[i] != rhs[i])

+                    return false;

+            return true;

+        }

+

+    }

+

+

+    [TestFixture]

+    public class CircBufferTests

+    {

+        #region Circular buffer tests

+        [Test]

+        public void SinglePutGet()

+        {

+            CircularBuffer buf = new CircularBuffer(10);

+            Assert.AreEqual( 0, buf.Size );

+            Assert.AreEqual( -1, buf.Get() );

+

+            Assert.IsTrue(buf.Put( 1 ));

+            Assert.AreEqual( 1, buf.Size );

+            Assert.AreEqual( 1, buf.Get() );

+            Assert.AreEqual( 0, buf.Size );

+            Assert.AreEqual( -1, buf.Get() );

+        }

+

+        [Test]

+        public void BlockPutGet()

+        {

+            CircularBuffer buf = new CircularBuffer(10);

+            byte[] arr = {1,2,3,4,5,6,7,8,9,10};

+            Assert.AreEqual( 10, buf.Put(arr,0,10) );

+            Assert.AreEqual( 10, buf.Size );

+            Assert.IsFalse( buf.Put(11) );

+            Assert.AreEqual( 1, buf.Get() );

+            Assert.IsTrue( buf.Put(11) );

+

+            byte[] arr2 = (byte[])arr.Clone();

+            Assert.AreEqual( 9, buf.Get(arr2,1,9) );

+            Assert.IsTrue( Utils.byteArrEqual(arr,arr2) );

+        }

+

+        #endregion

+    }

+

+    [TestFixture]

+    public class ChecksumTests

+    {

+        #region CRC32 Tests

+        [Test]

+        public void CRC32_Null()

+        {

+            CRC32Checksum crc32 = new CRC32Checksum();

+            Assert.AreEqual( 0, crc32.Value );

+

+            crc32 = new CRC32Checksum(1);

+            Assert.AreEqual( 1, crc32.Value );

+

+            crc32 = new CRC32Checksum(556);

+            Assert.AreEqual( 556, crc32.Value );

+        }

+

+        [Test]

+        public void CRC32_Data()

+        {

+            CRC32Checksum crc32 = new CRC32Checksum();

+            byte[] data = { 1,2,3,4,5,6,7 };

+            crc32.Update(data);

+            Assert.AreEqual( 0x70e46888, crc32.Value  );

+

+            crc32 = new CRC32Checksum();

+            crc32.Update("penguin");

+            Assert.AreEqual( 0x0e5c1a120, crc32.Value );

+

+            crc32 = new CRC32Checksum(1);

+            crc32.Update("penguin");

+            Assert.AreEqual(0x43b6aa94, crc32.Value);

+

+        }

+        #endregion

+

+        #region Adler tests

+

+        [Test]

+        public void Adler_Null()

+        {

+            AdlerChecksum adler = new AdlerChecksum();

+            Assert.AreEqual(0, adler.Value);

+

+            adler = new AdlerChecksum(1);

+            Assert.AreEqual( 1, adler.Value );

+

+            adler = new AdlerChecksum(556);

+            Assert.AreEqual( 556, adler.Value );

+        }

+

+        [Test]

+        public void Adler_Data()

+        {

+            AdlerChecksum adler = new AdlerChecksum(1);

+            byte[] data = { 1,2,3,4,5,6,7 };

+            adler.Update(data);

+            Assert.AreEqual( 0x5b001d, adler.Value  );

+

+            adler = new AdlerChecksum();

+            adler.Update("penguin");

+            Assert.AreEqual(0x0bcf02f6, adler.Value );

+

+            adler = new AdlerChecksum(1);

+            adler.Update("penguin");

+            Assert.AreEqual(0x0bd602f7, adler.Value);

+

+        }

+        #endregion

+    }

+

+    [TestFixture]

+    public class InfoTests

+    {

+        #region Info tests

+        [Test]

+        public void Info_Version()

+        {

+            Info info = new Info();

+            Assert.AreEqual("1.2.3", Info.Version);

+            Assert.AreEqual(32, info.SizeOfUInt);

+            Assert.AreEqual(32, info.SizeOfULong);

+            Assert.AreEqual(32, info.SizeOfPointer);

+            Assert.AreEqual(32, info.SizeOfOffset);

+        }

+        #endregion

+    }

+

+    [TestFixture]

+    public class DeflateInflateTests

+    {

+        #region Deflate tests

+        [Test]

+        public void Deflate_Init()

+        {

+            using (Deflater def = new Deflater(CompressLevel.Default))

+            {

+            }

+        }

+

+        private ArrayList compressedData = new ArrayList();

+        private uint adler1;

+

+        private ArrayList uncompressedData = new ArrayList();

+        private uint adler2;

+

+        public void CDataAvail(byte[] data, int startIndex, int count)

+        {

+            for (int i = 0; i < count; ++i)

+                compressedData.Add(data[i+startIndex]);

+        }

+

+        [Test]

+        public void Deflate_Compress()

+        {

+            compressedData.Clear();

+

+            byte[] testData = new byte[35000];

+            for (int i = 0; i < testData.Length; ++i)

+                testData[i] = 5;

+

+            using (Deflater def = new Deflater((CompressLevel)5))

+            {

+                def.DataAvailable += new DataAvailableHandler(CDataAvail);

+                def.Add(testData);

+                def.Finish();

+                adler1 = def.Checksum;

+            }

+        }

+        #endregion

+

+        #region Inflate tests

+        [Test]

+        public void Inflate_Init()

+        {

+            using (Inflater inf = new Inflater())

+            {

+            }

+        }

+

+        private void DDataAvail(byte[] data, int startIndex, int count)

+        {

+            for (int i = 0; i < count; ++i)

+                uncompressedData.Add(data[i+startIndex]);

+        }

+

+        [Test]

+        public void Inflate_Expand()

+        { 

+            uncompressedData.Clear();

+

+            using (Inflater inf = new Inflater())

+            {

+                inf.DataAvailable += new DataAvailableHandler(DDataAvail);

+                inf.Add((byte[])compressedData.ToArray(typeof(byte)));

+                inf.Finish();

+                adler2 = inf.Checksum;

+            }

+            Assert.AreEqual( adler1, adler2 );

+        }

+        #endregion

+    }

+

+    [TestFixture]

+    public class GZipStreamTests

+    {

+        #region GZipStream test

+        [Test]

+        public void GZipStream_WriteRead()

+        {

+            using (GZipStream gzOut = new GZipStream("gzstream.gz", CompressLevel.Best))

+            {

+                BinaryWriter writer = new BinaryWriter(gzOut);

+                writer.Write("hi there");

+                writer.Write(Math.PI);

+                writer.Write(42);

+            }

+

+            using (GZipStream gzIn = new GZipStream("gzstream.gz"))

+            {

+                BinaryReader reader = new BinaryReader(gzIn);

+                string s = reader.ReadString();

+                Assert.AreEqual("hi there",s);

+                double d = reader.ReadDouble();

+                Assert.AreEqual(Math.PI, d);

+                int i = reader.ReadInt32();

+                Assert.AreEqual(42,i);

+            }

+

+        }

+        #endregion

+	}

+}

+

+#endif
\ No newline at end of file
diff --git a/gs/zlib/contrib/dotzlib/LICENSE_1_0.txt b/gs/zlib/contrib/dotzlib/LICENSE_1_0.txt
new file mode 100644
index 000000000..30aac2cf4
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/LICENSE_1_0.txt
@@ -0,0 +1,23 @@
+Boost Software License - Version 1.0 - August 17th, 2003

+

+Permission is hereby granted, free of charge, to any person or organization

+obtaining a copy of the software and accompanying documentation covered by

+this license (the "Software") to use, reproduce, display, distribute,

+execute, and transmit the Software, and to prepare derivative works of the

+Software, and to permit third-parties to whom the Software is furnished to

+do so, all subject to the following:

+

+The copyright notices in the Software and this entire statement, including

+the above license grant, this restriction and the following disclaimer,

+must be included in all copies of the Software, in whole or in part, and

+all derivative works of the Software, unless such copies or derivative

+works are solely in the form of machine-executable object code generated by

+a source language processor.

+

+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

+FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT

+SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE

+FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,

+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER

+DEALINGS IN THE SOFTWARE.
\ No newline at end of file
diff --git a/gs/zlib/contrib/dotzlib/readme.txt b/gs/zlib/contrib/dotzlib/readme.txt
new file mode 100644
index 000000000..210f4b001
--- /dev/null
+++ b/gs/zlib/contrib/dotzlib/readme.txt
@@ -0,0 +1,58 @@
+This directory contains a .Net wrapper class library for the ZLib1.dll

+

+The wrapper includes support for inflating/deflating memory buffers, 

+.Net streaming wrappers for the gz streams part of zlib, and wrappers

+for the checksum parts of zlib. See DotZLib/UnitTests.cs for examples.

+

+Directory structure:

+--------------------

+

+LICENSE_1_0.txt       - License file.

+readme.txt            - This file.

+DotZLib.chm           - Class library documentation

+DotZLib.build         - NAnt build file

+DotZLib.sln           - Microsoft Visual Studio 2003 solution file

+

+DotZLib\*.cs          - Source files for the class library

+

+Unit tests:

+-----------

+The file DotZLib/UnitTests.cs contains unit tests for use with NUnit 2.1 or higher.

+To include unit tests in the build, define nunit before building.

+

+

+Build instructions:

+-------------------

+

+1. Using Visual Studio.Net 2003:

+   Open DotZLib.sln in VS.Net and build from there. Output file (DotZLib.dll)

+   will be found ./DotZLib/bin/release or ./DotZLib/bin/debug, depending on 

+   you are building the release or debug version of the library. Check 

+   DotZLib/UnitTests.cs for instructions on how to include unit tests in the

+   build.

+   

+2. Using NAnt:

+   Open a command prompt with access to the build environment and run nant

+   in the same directory as the DotZLib.build file.

+   You can define 2 properties on the nant command-line to control the build:

+   debug={true|false} to toggle between release/debug builds (default=true).

+   nunit={true|false} to include or esclude unit tests (default=true).

+   Also the target clean will remove binaries.

+   Output file (DotZLib.dll) will be found in either ./DotZLib/bin/release 

+   or ./DotZLib/bin/debug, depending on whether you are building the release 

+   or debug version of the library.

+

+   Examples: 

+     nant -D:debug=false -D:nunit=false

+       will build a release mode version of the library without unit tests.

+     nant

+       will build a debug version of the library with unit tests 

+     nant clean

+       will remove all previously built files.

+

+

+---------------------------------

+Copyright (c) Henrik Ravn 2004

+

+Use, modification and distribution are subject to the Boost Software License, Version 1.0. 

+(See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

diff --git a/gs/zlib/contrib/infback9/README b/gs/zlib/contrib/infback9/README
new file mode 100644
index 000000000..e75ed1329
--- /dev/null
+++ b/gs/zlib/contrib/infback9/README
@@ -0,0 +1 @@
+See infback9.h for what this is and how to use it.
diff --git a/gs/zlib/contrib/infback9/infback9.c b/gs/zlib/contrib/infback9/infback9.c
new file mode 100644
index 000000000..f5ddde67d
--- /dev/null
+++ b/gs/zlib/contrib/infback9/infback9.c
@@ -0,0 +1,608 @@
+/* infback9.c -- inflate deflate64 data using a call-back interface
+ * Copyright (C) 1995-2003 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#include "zutil.h"
+#include "infback9.h"
+#include "inftree9.h"
+#include "inflate9.h"
+
+#define WSIZE 65536UL
+
+/*
+   strm provides memory allocation functions in zalloc and zfree, or
+   Z_NULL to use the library memory allocation functions.
+
+   window is a user-supplied window and output buffer that is 64K bytes.
+ */
+int ZEXPORT inflateBack9Init_(strm, window, version, stream_size)
+z_stream FAR *strm;
+unsigned char FAR *window;
+const char *version;
+int stream_size;
+{
+    struct inflate_state FAR *state;
+
+    if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
+        stream_size != (int)(sizeof(z_stream)))
+        return Z_VERSION_ERROR;
+    if (strm == Z_NULL || window == Z_NULL)
+        return Z_STREAM_ERROR;
+    strm->msg = Z_NULL;                 /* in case we return an error */
+    if (strm->zalloc == (alloc_func)0) {
+        strm->zalloc = zcalloc;
+        strm->opaque = (voidpf)0;
+    }
+    if (strm->zfree == (free_func)0) strm->zfree = zcfree;
+    state = (struct inflate_state FAR *)ZALLOC(strm, 1,
+                                               sizeof(struct inflate_state));
+    if (state == Z_NULL) return Z_MEM_ERROR;
+    Tracev((stderr, "inflate: allocated\n"));
+    strm->state = (voidpf)state;
+    state->window = window;
+    return Z_OK;
+}
+
+/*
+   Build and output length and distance decoding tables for fixed code
+   decoding.
+ */
+#ifdef MAKEFIXED
+#include <stdio.h>
+
+void makefixed9(void)
+{
+    unsigned sym, bits, low, size;
+    code *next, *lenfix, *distfix;
+    struct inflate_state state;
+    code fixed[544];
+
+    /* literal/length table */
+    sym = 0;
+    while (sym < 144) state.lens[sym++] = 8;
+    while (sym < 256) state.lens[sym++] = 9;
+    while (sym < 280) state.lens[sym++] = 7;
+    while (sym < 288) state.lens[sym++] = 8;
+    next = fixed;
+    lenfix = next;
+    bits = 9;
+    inflate_table9(LENS, state.lens, 288, &(next), &(bits), state.work);
+
+    /* distance table */
+    sym = 0;
+    while (sym < 32) state.lens[sym++] = 5;
+    distfix = next;
+    bits = 5;
+    inflate_table9(DISTS, state.lens, 32, &(next), &(bits), state.work);
+
+    /* write tables */
+    puts("    /* inffix9.h -- table for decoding deflate64 fixed codes");
+    puts("     * Generated automatically by makefixed9().");
+    puts("     */");
+    puts("");
+    puts("    /* WARNING: this file should *not* be used by applications.");
+    puts("       It is part of the implementation of this library and is");
+    puts("       subject to change. Applications should only use zlib.h.");
+    puts("     */");
+    puts("");
+    size = 1U << 9;
+    printf("    static const code lenfix[%u] = {", size);
+    low = 0;
+    for (;;) {
+        if ((low % 6) == 0) printf("\n        ");
+        printf("{%u,%u,%d}", lenfix[low].op, lenfix[low].bits,
+               lenfix[low].val);
+        if (++low == size) break;
+        putchar(',');
+    }
+    puts("\n    };");
+    size = 1U << 5;
+    printf("\n    static const code distfix[%u] = {", size);
+    low = 0;
+    for (;;) {
+        if ((low % 5) == 0) printf("\n        ");
+        printf("{%u,%u,%d}", distfix[low].op, distfix[low].bits,
+               distfix[low].val);
+        if (++low == size) break;
+        putchar(',');
+    }
+    puts("\n    };");
+}
+#endif /* MAKEFIXED */
+
+/* Macros for inflateBack(): */
+
+/* Clear the input bit accumulator */
+#define INITBITS() \
+    do { \
+        hold = 0; \
+        bits = 0; \
+    } while (0)
+
+/* Assure that some input is available.  If input is requested, but denied,
+   then return a Z_BUF_ERROR from inflateBack(). */
+#define PULL() \
+    do { \
+        if (have == 0) { \
+            have = in(in_desc, &next); \
+            if (have == 0) { \
+                next = Z_NULL; \
+                ret = Z_BUF_ERROR; \
+                goto inf_leave; \
+            } \
+        } \
+    } while (0)
+
+/* Get a byte of input into the bit accumulator, or return from inflateBack()
+   with an error if there is no input available. */
+#define PULLBYTE() \
+    do { \
+        PULL(); \
+        have--; \
+        hold += (unsigned long)(*next++) << bits; \
+        bits += 8; \
+    } while (0)
+
+/* Assure that there are at least n bits in the bit accumulator.  If there is
+   not enough available input to do that, then return from inflateBack() with
+   an error. */
+#define NEEDBITS(n) \
+    do { \
+        while (bits < (unsigned)(n)) \
+            PULLBYTE(); \
+    } while (0)
+
+/* Return the low n bits of the bit accumulator (n <= 16) */
+#define BITS(n) \
+    ((unsigned)hold & ((1U << (n)) - 1))
+
+/* Remove n bits from the bit accumulator */
+#define DROPBITS(n) \
+    do { \
+        hold >>= (n); \
+        bits -= (unsigned)(n); \
+    } while (0)
+
+/* Remove zero to seven bits as needed to go to a byte boundary */
+#define BYTEBITS() \
+    do { \
+        hold >>= bits & 7; \
+        bits -= bits & 7; \
+    } while (0)
+
+/* Assure that some output space is available, by writing out the window
+   if it's full.  If the write fails, return from inflateBack() with a
+   Z_BUF_ERROR. */
+#define ROOM() \
+    do { \
+        if (left == 0) { \
+            put = window; \
+            left = WSIZE; \
+            wrap = 1; \
+            if (out(out_desc, put, (unsigned)left)) { \
+                ret = Z_BUF_ERROR; \
+                goto inf_leave; \
+            } \
+        } \
+    } while (0)
+
+/*
+   strm provides the memory allocation functions and window buffer on input,
+   and provides information on the unused input on return.  For Z_DATA_ERROR
+   returns, strm will also provide an error message.
+
+   in() and out() are the call-back input and output functions.  When
+   inflateBack() needs more input, it calls in().  When inflateBack() has
+   filled the window with output, or when it completes with data in the
+   window, it calls out() to write out the data.  The application must not
+   change the provided input until in() is called again or inflateBack()
+   returns.  The application must not change the window/output buffer until
+   inflateBack() returns.
+
+   in() and out() are called with a descriptor parameter provided in the
+   inflateBack() call.  This parameter can be a structure that provides the
+   information required to do the read or write, as well as accumulated
+   information on the input and output such as totals and check values.
+
+   in() should return zero on failure.  out() should return non-zero on
+   failure.  If either in() or out() fails, than inflateBack() returns a
+   Z_BUF_ERROR.  strm->next_in can be checked for Z_NULL to see whether it
+   was in() or out() that caused in the error.  Otherwise,  inflateBack()
+   returns Z_STREAM_END on success, Z_DATA_ERROR for an deflate format
+   error, or Z_MEM_ERROR if it could not allocate memory for the state.
+   inflateBack() can also return Z_STREAM_ERROR if the input parameters
+   are not correct, i.e. strm is Z_NULL or the state was not initialized.
+ */
+int ZEXPORT inflateBack9(strm, in, in_desc, out, out_desc)
+z_stream FAR *strm;
+in_func in;
+void FAR *in_desc;
+out_func out;
+void FAR *out_desc;
+{
+    struct inflate_state FAR *state;
+    unsigned char FAR *next;    /* next input */
+    unsigned char FAR *put;     /* next output */
+    unsigned have;              /* available input */
+    unsigned long left;         /* available output */
+    inflate_mode mode;          /* current inflate mode */
+    int lastblock;              /* true if processing last block */
+    int wrap;                   /* true if the window has wrapped */
+    unsigned long write;        /* window write index */
+    unsigned char FAR *window;  /* allocated sliding window, if needed */
+    unsigned long hold;         /* bit buffer */
+    unsigned bits;              /* bits in bit buffer */
+    unsigned extra;             /* extra bits needed */
+    unsigned long length;       /* literal or length of data to copy */
+    unsigned long offset;       /* distance back to copy string from */
+    unsigned long copy;         /* number of stored or match bytes to copy */
+    unsigned char FAR *from;    /* where to copy match bytes from */
+    code const FAR *lencode;    /* starting table for length/literal codes */
+    code const FAR *distcode;   /* starting table for distance codes */
+    unsigned lenbits;           /* index bits for lencode */
+    unsigned distbits;          /* index bits for distcode */
+    code this;                  /* current decoding table entry */
+    code last;                  /* parent table entry */
+    unsigned len;               /* length to copy for repeats, bits to drop */
+    int ret;                    /* return code */
+    static const unsigned short order[19] = /* permutation of code lengths */
+        {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
+#include "inffix9.h"
+
+    /* Check that the strm exists and that the state was initialized */
+    if (strm == Z_NULL || strm->state == Z_NULL)
+        return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)strm->state;
+
+    /* Reset the state */
+    strm->msg = Z_NULL;
+    mode = TYPE;
+    lastblock = 0;
+    write = 0;
+    wrap = 0;
+    window = state->window;
+    next = strm->next_in;
+    have = next != Z_NULL ? strm->avail_in : 0;
+    hold = 0;
+    bits = 0;
+    put = window;
+    left = WSIZE;
+    lencode = Z_NULL;
+    distcode = Z_NULL;
+
+    /* Inflate until end of block marked as last */
+    for (;;)
+        switch (mode) {
+        case TYPE:
+            /* determine and dispatch block type */
+            if (lastblock) {
+                BYTEBITS();
+                mode = DONE;
+                break;
+            }
+            NEEDBITS(3);
+            lastblock = BITS(1);
+            DROPBITS(1);
+            switch (BITS(2)) {
+            case 0:                             /* stored block */
+                Tracev((stderr, "inflate:     stored block%s\n",
+                        lastblock ? " (last)" : ""));
+                mode = STORED;
+                break;
+            case 1:                             /* fixed block */
+                lencode = lenfix;
+                lenbits = 9;
+                distcode = distfix;
+                distbits = 5;
+                Tracev((stderr, "inflate:     fixed codes block%s\n",
+                        lastblock ? " (last)" : ""));
+                mode = LEN;                     /* decode codes */
+                break;
+            case 2:                             /* dynamic block */
+                Tracev((stderr, "inflate:     dynamic codes block%s\n",
+                        lastblock ? " (last)" : ""));
+                mode = TABLE;
+                break;
+            case 3:
+                strm->msg = (char *)"invalid block type";
+                mode = BAD;
+            }
+            DROPBITS(2);
+            break;
+
+        case STORED:
+            /* get and verify stored block length */
+            BYTEBITS();                         /* go to byte boundary */
+            NEEDBITS(32);
+            if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
+                strm->msg = (char *)"invalid stored block lengths";
+                mode = BAD;
+                break;
+            }
+            length = (unsigned)hold & 0xffff;
+            Tracev((stderr, "inflate:       stored length %lu\n",
+                    length));
+            INITBITS();
+
+            /* copy stored block from input to output */
+            while (length != 0) {
+                copy = length;
+                PULL();
+                ROOM();
+                if (copy > have) copy = have;
+                if (copy > left) copy = left;
+                zmemcpy(put, next, copy);
+                have -= copy;
+                next += copy;
+                left -= copy;
+                put += copy;
+                length -= copy;
+            }
+            Tracev((stderr, "inflate:       stored end\n"));
+            mode = TYPE;
+            break;
+
+        case TABLE:
+            /* get dynamic table entries descriptor */
+            NEEDBITS(14);
+            state->nlen = BITS(5) + 257;
+            DROPBITS(5);
+            state->ndist = BITS(5) + 1;
+            DROPBITS(5);
+            state->ncode = BITS(4) + 4;
+            DROPBITS(4);
+            if (state->nlen > 286) {
+                strm->msg = (char *)"too many length symbols";
+                mode = BAD;
+                break;
+            }
+            Tracev((stderr, "inflate:       table sizes ok\n"));
+
+            /* get code length code lengths (not a typo) */
+            state->have = 0;
+            while (state->have < state->ncode) {
+                NEEDBITS(3);
+                state->lens[order[state->have++]] = (unsigned short)BITS(3);
+                DROPBITS(3);
+            }
+            while (state->have < 19)
+                state->lens[order[state->have++]] = 0;
+            state->next = state->codes;
+            lencode = (code const FAR *)(state->next);
+            lenbits = 7;
+            ret = inflate_table9(CODES, state->lens, 19, &(state->next),
+                                &(lenbits), state->work);
+            if (ret) {
+                strm->msg = (char *)"invalid code lengths set";
+                mode = BAD;
+                break;
+            }
+            Tracev((stderr, "inflate:       code lengths ok\n"));
+
+            /* get length and distance code code lengths */
+            state->have = 0;
+            while (state->have < state->nlen + state->ndist) {
+                for (;;) {
+                    this = lencode[BITS(lenbits)];
+                    if ((unsigned)(this.bits) <= bits) break;
+                    PULLBYTE();
+                }
+                if (this.val < 16) {
+                    NEEDBITS(this.bits);
+                    DROPBITS(this.bits);
+                    state->lens[state->have++] = this.val;
+                }
+                else {
+                    if (this.val == 16) {
+                        NEEDBITS(this.bits + 2);
+                        DROPBITS(this.bits);
+                        if (state->have == 0) {
+                            strm->msg = (char *)"invalid bit length repeat";
+                            mode = BAD;
+                            break;
+                        }
+                        len = (unsigned)(state->lens[state->have - 1]);
+                        copy = 3 + BITS(2);
+                        DROPBITS(2);
+                    }
+                    else if (this.val == 17) {
+                        NEEDBITS(this.bits + 3);
+                        DROPBITS(this.bits);
+                        len = 0;
+                        copy = 3 + BITS(3);
+                        DROPBITS(3);
+                    }
+                    else {
+                        NEEDBITS(this.bits + 7);
+                        DROPBITS(this.bits);
+                        len = 0;
+                        copy = 11 + BITS(7);
+                        DROPBITS(7);
+                    }
+                    if (state->have + copy > state->nlen + state->ndist) {
+                        strm->msg = (char *)"invalid bit length repeat";
+                        mode = BAD;
+                        break;
+                    }
+                    while (copy--)
+                        state->lens[state->have++] = (unsigned short)len;
+                }
+            }
+
+            /* handle error breaks in while */
+            if (mode == BAD) break;
+
+            /* build code tables */
+            state->next = state->codes;
+            lencode = (code const FAR *)(state->next);
+            lenbits = 9;
+            ret = inflate_table9(LENS, state->lens, state->nlen,
+                            &(state->next), &(lenbits), state->work);
+            if (ret) {
+                strm->msg = (char *)"invalid literal/lengths set";
+                mode = BAD;
+                break;
+            }
+            distcode = (code const FAR *)(state->next);
+            distbits = 6;
+            ret = inflate_table9(DISTS, state->lens + state->nlen,
+                            state->ndist, &(state->next), &(distbits),
+                            state->work);
+            if (ret) {
+                strm->msg = (char *)"invalid distances set";
+                mode = BAD;
+                break;
+            }
+            Tracev((stderr, "inflate:       codes ok\n"));
+            mode = LEN;
+
+        case LEN:
+            /* get a literal, length, or end-of-block code */
+            for (;;) {
+                this = lencode[BITS(lenbits)];
+                if ((unsigned)(this.bits) <= bits) break;
+                PULLBYTE();
+            }
+            if (this.op && (this.op & 0xf0) == 0) {
+                last = this;
+                for (;;) {
+                    this = lencode[last.val +
+                            (BITS(last.bits + last.op) >> last.bits)];
+                    if ((unsigned)(last.bits + this.bits) <= bits) break;
+                    PULLBYTE();
+                }
+                DROPBITS(last.bits);
+            }
+            DROPBITS(this.bits);
+            length = (unsigned)this.val;
+
+            /* process literal */
+            if (this.op == 0) {
+                Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ?
+                        "inflate:         literal '%c'\n" :
+                        "inflate:         literal 0x%02x\n", this.val));
+                ROOM();
+                *put++ = (unsigned char)(length);
+                left--;
+                mode = LEN;
+                break;
+            }
+
+            /* process end of block */
+            if (this.op & 32) {
+                Tracevv((stderr, "inflate:         end of block\n"));
+                mode = TYPE;
+                break;
+            }
+
+            /* invalid code */
+            if (this.op & 64) {
+                strm->msg = (char *)"invalid literal/length code";
+                mode = BAD;
+                break;
+            }
+
+            /* length code -- get extra bits, if any */
+            extra = (unsigned)(this.op) & 31;
+            if (extra != 0) {
+                NEEDBITS(extra);
+                length += BITS(extra);
+                DROPBITS(extra);
+            }
+            Tracevv((stderr, "inflate:         length %lu\n", length));
+
+            /* get distance code */
+            for (;;) {
+                this = distcode[BITS(distbits)];
+                if ((unsigned)(this.bits) <= bits) break;
+                PULLBYTE();
+            }
+            if ((this.op & 0xf0) == 0) {
+                last = this;
+                for (;;) {
+                    this = distcode[last.val +
+                            (BITS(last.bits + last.op) >> last.bits)];
+                    if ((unsigned)(last.bits + this.bits) <= bits) break;
+                    PULLBYTE();
+                }
+                DROPBITS(last.bits);
+            }
+            DROPBITS(this.bits);
+            if (this.op & 64) {
+                strm->msg = (char *)"invalid distance code";
+                mode = BAD;
+                break;
+            }
+            offset = (unsigned)this.val;
+
+            /* get distance extra bits, if any */
+            extra = (unsigned)(this.op) & 15;
+            if (extra != 0) {
+                NEEDBITS(extra);
+                offset += BITS(extra);
+                DROPBITS(extra);
+            }
+            if (offset > WSIZE - (wrap ? 0: left)) {
+                strm->msg = (char *)"invalid distance too far back";
+                mode = BAD;
+                break;
+            }
+            Tracevv((stderr, "inflate:         distance %lu\n", offset));
+
+            /* copy match from window to output */
+            do {
+                ROOM();
+                copy = WSIZE - offset;
+                if (copy < left) {
+                    from = put + copy;
+                    copy = left - copy;
+                }
+                else {
+                    from = put - offset;
+                    copy = left;
+                }
+                if (copy > length) copy = length;
+                length -= copy;
+                left -= copy;
+                do {
+                    *put++ = *from++;
+                } while (--copy);
+            } while (length != 0);
+            break;
+
+        case DONE:
+            /* inflate stream terminated properly -- write leftover output */
+            ret = Z_STREAM_END;
+            if (left < WSIZE) {
+                if (out(out_desc, window, (unsigned)(WSIZE - left)))
+                    ret = Z_BUF_ERROR;
+            }
+            goto inf_leave;
+
+        case BAD:
+            ret = Z_DATA_ERROR;
+            goto inf_leave;
+
+        default:                /* can't happen, but makes compilers happy */
+            ret = Z_STREAM_ERROR;
+            goto inf_leave;
+        }
+
+    /* Return unused input */
+  inf_leave:
+    strm->next_in = next;
+    strm->avail_in = have;
+    return ret;
+}
+
+int ZEXPORT inflateBack9End(strm)
+z_stream FAR *strm;
+{
+    if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0)
+        return Z_STREAM_ERROR;
+    ZFREE(strm, strm->state);
+    strm->state = Z_NULL;
+    Tracev((stderr, "inflate: end\n"));
+    return Z_OK;
+}
diff --git a/gs/zlib/contrib/infback9/infback9.h b/gs/zlib/contrib/infback9/infback9.h
new file mode 100644
index 000000000..1073c0a38
--- /dev/null
+++ b/gs/zlib/contrib/infback9/infback9.h
@@ -0,0 +1,37 @@
+/* infback9.h -- header for using inflateBack9 functions
+ * Copyright (C) 2003 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/*
+ * This header file and associated patches provide a decoder for PKWare's
+ * undocumented deflate64 compression method (method 9).  Use with infback9.c,
+ * inftree9.h, inftree9.c, and inffix9.h.  These patches are not supported.
+ * This should be compiled with zlib, since it uses zutil.h and zutil.o.
+ * This code has not yet been tested on 16-bit architectures.  See the
+ * comments in zlib.h for inflateBack() usage.  These functions are used
+ * identically, except that there is no windowBits parameter, and a 64K
+ * window must be provided.  Also if int's are 16 bits, then a zero for
+ * the third parameter of the "out" function actually means 65536UL.
+ * zlib.h must be included before this header file.
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+ZEXTERN int ZEXPORT inflateBack9 OF((z_stream FAR *strm,
+                                    in_func in, void FAR *in_desc,
+                                    out_func out, void FAR *out_desc));
+ZEXTERN int ZEXPORT inflateBack9End OF((z_stream FAR *strm));
+ZEXTERN int ZEXPORT inflateBack9Init_ OF((z_stream FAR *strm,
+                                         unsigned char FAR *window,
+                                         const char *version,
+                                         int stream_size));
+#define inflateBack9Init(strm, window) \
+        inflateBack9Init_((strm), (window), \
+        ZLIB_VERSION, sizeof(z_stream))
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/gs/zlib/contrib/infback9/inffix9.h b/gs/zlib/contrib/infback9/inffix9.h
new file mode 100644
index 000000000..ee5671d2d
--- /dev/null
+++ b/gs/zlib/contrib/infback9/inffix9.h
@@ -0,0 +1,107 @@
+    /* inffix9.h -- table for decoding deflate64 fixed codes
+     * Generated automatically by makefixed9().
+     */
+
+    /* WARNING: this file should *not* be used by applications.
+       It is part of the implementation of this library and is
+       subject to change. Applications should only use zlib.h.
+     */
+
+    static const code lenfix[512] = {
+        {96,7,0},{0,8,80},{0,8,16},{132,8,115},{130,7,31},{0,8,112},
+        {0,8,48},{0,9,192},{128,7,10},{0,8,96},{0,8,32},{0,9,160},
+        {0,8,0},{0,8,128},{0,8,64},{0,9,224},{128,7,6},{0,8,88},
+        {0,8,24},{0,9,144},{131,7,59},{0,8,120},{0,8,56},{0,9,208},
+        {129,7,17},{0,8,104},{0,8,40},{0,9,176},{0,8,8},{0,8,136},
+        {0,8,72},{0,9,240},{128,7,4},{0,8,84},{0,8,20},{133,8,227},
+        {131,7,43},{0,8,116},{0,8,52},{0,9,200},{129,7,13},{0,8,100},
+        {0,8,36},{0,9,168},{0,8,4},{0,8,132},{0,8,68},{0,9,232},
+        {128,7,8},{0,8,92},{0,8,28},{0,9,152},{132,7,83},{0,8,124},
+        {0,8,60},{0,9,216},{130,7,23},{0,8,108},{0,8,44},{0,9,184},
+        {0,8,12},{0,8,140},{0,8,76},{0,9,248},{128,7,3},{0,8,82},
+        {0,8,18},{133,8,163},{131,7,35},{0,8,114},{0,8,50},{0,9,196},
+        {129,7,11},{0,8,98},{0,8,34},{0,9,164},{0,8,2},{0,8,130},
+        {0,8,66},{0,9,228},{128,7,7},{0,8,90},{0,8,26},{0,9,148},
+        {132,7,67},{0,8,122},{0,8,58},{0,9,212},{130,7,19},{0,8,106},
+        {0,8,42},{0,9,180},{0,8,10},{0,8,138},{0,8,74},{0,9,244},
+        {128,7,5},{0,8,86},{0,8,22},{65,8,0},{131,7,51},{0,8,118},
+        {0,8,54},{0,9,204},{129,7,15},{0,8,102},{0,8,38},{0,9,172},
+        {0,8,6},{0,8,134},{0,8,70},{0,9,236},{128,7,9},{0,8,94},
+        {0,8,30},{0,9,156},{132,7,99},{0,8,126},{0,8,62},{0,9,220},
+        {130,7,27},{0,8,110},{0,8,46},{0,9,188},{0,8,14},{0,8,142},
+        {0,8,78},{0,9,252},{96,7,0},{0,8,81},{0,8,17},{133,8,131},
+        {130,7,31},{0,8,113},{0,8,49},{0,9,194},{128,7,10},{0,8,97},
+        {0,8,33},{0,9,162},{0,8,1},{0,8,129},{0,8,65},{0,9,226},
+        {128,7,6},{0,8,89},{0,8,25},{0,9,146},{131,7,59},{0,8,121},
+        {0,8,57},{0,9,210},{129,7,17},{0,8,105},{0,8,41},{0,9,178},
+        {0,8,9},{0,8,137},{0,8,73},{0,9,242},{128,7,4},{0,8,85},
+        {0,8,21},{144,8,3},{131,7,43},{0,8,117},{0,8,53},{0,9,202},
+        {129,7,13},{0,8,101},{0,8,37},{0,9,170},{0,8,5},{0,8,133},
+        {0,8,69},{0,9,234},{128,7,8},{0,8,93},{0,8,29},{0,9,154},
+        {132,7,83},{0,8,125},{0,8,61},{0,9,218},{130,7,23},{0,8,109},
+        {0,8,45},{0,9,186},{0,8,13},{0,8,141},{0,8,77},{0,9,250},
+        {128,7,3},{0,8,83},{0,8,19},{133,8,195},{131,7,35},{0,8,115},
+        {0,8,51},{0,9,198},{129,7,11},{0,8,99},{0,8,35},{0,9,166},
+        {0,8,3},{0,8,131},{0,8,67},{0,9,230},{128,7,7},{0,8,91},
+        {0,8,27},{0,9,150},{132,7,67},{0,8,123},{0,8,59},{0,9,214},
+        {130,7,19},{0,8,107},{0,8,43},{0,9,182},{0,8,11},{0,8,139},
+        {0,8,75},{0,9,246},{128,7,5},{0,8,87},{0,8,23},{77,8,0},
+        {131,7,51},{0,8,119},{0,8,55},{0,9,206},{129,7,15},{0,8,103},
+        {0,8,39},{0,9,174},{0,8,7},{0,8,135},{0,8,71},{0,9,238},
+        {128,7,9},{0,8,95},{0,8,31},{0,9,158},{132,7,99},{0,8,127},
+        {0,8,63},{0,9,222},{130,7,27},{0,8,111},{0,8,47},{0,9,190},
+        {0,8,15},{0,8,143},{0,8,79},{0,9,254},{96,7,0},{0,8,80},
+        {0,8,16},{132,8,115},{130,7,31},{0,8,112},{0,8,48},{0,9,193},
+        {128,7,10},{0,8,96},{0,8,32},{0,9,161},{0,8,0},{0,8,128},
+        {0,8,64},{0,9,225},{128,7,6},{0,8,88},{0,8,24},{0,9,145},
+        {131,7,59},{0,8,120},{0,8,56},{0,9,209},{129,7,17},{0,8,104},
+        {0,8,40},{0,9,177},{0,8,8},{0,8,136},{0,8,72},{0,9,241},
+        {128,7,4},{0,8,84},{0,8,20},{133,8,227},{131,7,43},{0,8,116},
+        {0,8,52},{0,9,201},{129,7,13},{0,8,100},{0,8,36},{0,9,169},
+        {0,8,4},{0,8,132},{0,8,68},{0,9,233},{128,7,8},{0,8,92},
+        {0,8,28},{0,9,153},{132,7,83},{0,8,124},{0,8,60},{0,9,217},
+        {130,7,23},{0,8,108},{0,8,44},{0,9,185},{0,8,12},{0,8,140},
+        {0,8,76},{0,9,249},{128,7,3},{0,8,82},{0,8,18},{133,8,163},
+        {131,7,35},{0,8,114},{0,8,50},{0,9,197},{129,7,11},{0,8,98},
+        {0,8,34},{0,9,165},{0,8,2},{0,8,130},{0,8,66},{0,9,229},
+        {128,7,7},{0,8,90},{0,8,26},{0,9,149},{132,7,67},{0,8,122},
+        {0,8,58},{0,9,213},{130,7,19},{0,8,106},{0,8,42},{0,9,181},
+        {0,8,10},{0,8,138},{0,8,74},{0,9,245},{128,7,5},{0,8,86},
+        {0,8,22},{65,8,0},{131,7,51},{0,8,118},{0,8,54},{0,9,205},
+        {129,7,15},{0,8,102},{0,8,38},{0,9,173},{0,8,6},{0,8,134},
+        {0,8,70},{0,9,237},{128,7,9},{0,8,94},{0,8,30},{0,9,157},
+        {132,7,99},{0,8,126},{0,8,62},{0,9,221},{130,7,27},{0,8,110},
+        {0,8,46},{0,9,189},{0,8,14},{0,8,142},{0,8,78},{0,9,253},
+        {96,7,0},{0,8,81},{0,8,17},{133,8,131},{130,7,31},{0,8,113},
+        {0,8,49},{0,9,195},{128,7,10},{0,8,97},{0,8,33},{0,9,163},
+        {0,8,1},{0,8,129},{0,8,65},{0,9,227},{128,7,6},{0,8,89},
+        {0,8,25},{0,9,147},{131,7,59},{0,8,121},{0,8,57},{0,9,211},
+        {129,7,17},{0,8,105},{0,8,41},{0,9,179},{0,8,9},{0,8,137},
+        {0,8,73},{0,9,243},{128,7,4},{0,8,85},{0,8,21},{144,8,3},
+        {131,7,43},{0,8,117},{0,8,53},{0,9,203},{129,7,13},{0,8,101},
+        {0,8,37},{0,9,171},{0,8,5},{0,8,133},{0,8,69},{0,9,235},
+        {128,7,8},{0,8,93},{0,8,29},{0,9,155},{132,7,83},{0,8,125},
+        {0,8,61},{0,9,219},{130,7,23},{0,8,109},{0,8,45},{0,9,187},
+        {0,8,13},{0,8,141},{0,8,77},{0,9,251},{128,7,3},{0,8,83},
+        {0,8,19},{133,8,195},{131,7,35},{0,8,115},{0,8,51},{0,9,199},
+        {129,7,11},{0,8,99},{0,8,35},{0,9,167},{0,8,3},{0,8,131},
+        {0,8,67},{0,9,231},{128,7,7},{0,8,91},{0,8,27},{0,9,151},
+        {132,7,67},{0,8,123},{0,8,59},{0,9,215},{130,7,19},{0,8,107},
+        {0,8,43},{0,9,183},{0,8,11},{0,8,139},{0,8,75},{0,9,247},
+        {128,7,5},{0,8,87},{0,8,23},{77,8,0},{131,7,51},{0,8,119},
+        {0,8,55},{0,9,207},{129,7,15},{0,8,103},{0,8,39},{0,9,175},
+        {0,8,7},{0,8,135},{0,8,71},{0,9,239},{128,7,9},{0,8,95},
+        {0,8,31},{0,9,159},{132,7,99},{0,8,127},{0,8,63},{0,9,223},
+        {130,7,27},{0,8,111},{0,8,47},{0,9,191},{0,8,15},{0,8,143},
+        {0,8,79},{0,9,255}
+    };
+
+    static const code distfix[32] = {
+        {128,5,1},{135,5,257},{131,5,17},{139,5,4097},{129,5,5},
+        {137,5,1025},{133,5,65},{141,5,16385},{128,5,3},{136,5,513},
+        {132,5,33},{140,5,8193},{130,5,9},{138,5,2049},{134,5,129},
+        {142,5,32769},{128,5,2},{135,5,385},{131,5,25},{139,5,6145},
+        {129,5,7},{137,5,1537},{133,5,97},{141,5,24577},{128,5,4},
+        {136,5,769},{132,5,49},{140,5,12289},{130,5,13},{138,5,3073},
+        {134,5,193},{142,5,49153}
+    };
diff --git a/gs/zlib/contrib/infback9/inflate9.h b/gs/zlib/contrib/infback9/inflate9.h
new file mode 100644
index 000000000..ee9a79394
--- /dev/null
+++ b/gs/zlib/contrib/infback9/inflate9.h
@@ -0,0 +1,47 @@
+/* inflate9.h -- internal inflate state definition
+ * Copyright (C) 1995-2003 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* WARNING: this file should *not* be used by applications. It is
+   part of the implementation of the compression library and is
+   subject to change. Applications should only use zlib.h.
+ */
+
+/* Possible inflate modes between inflate() calls */
+typedef enum {
+        TYPE,       /* i: waiting for type bits, including last-flag bit */
+        STORED,     /* i: waiting for stored size (length and complement) */
+        TABLE,      /* i: waiting for dynamic block table lengths */
+            LEN,        /* i: waiting for length/lit code */
+    DONE,       /* finished check, done -- remain here until reset */
+    BAD         /* got a data error -- remain here until reset */
+} inflate_mode;
+
+/*
+    State transitions between above modes -
+
+    (most modes can go to the BAD mode -- not shown for clarity)
+
+    Read deflate blocks:
+            TYPE -> STORED or TABLE or LEN or DONE
+            STORED -> TYPE
+            TABLE -> LENLENS -> CODELENS -> LEN
+    Read deflate codes:
+                LEN -> LEN or TYPE
+ */
+
+/* state maintained between inflate() calls.  Approximately 7K bytes. */
+struct inflate_state {
+        /* sliding window */
+    unsigned char FAR *window;  /* allocated sliding window, if needed */
+        /* dynamic table building */
+    unsigned ncode;             /* number of code length code lengths */
+    unsigned nlen;              /* number of length code lengths */
+    unsigned ndist;             /* number of distance code lengths */
+    unsigned have;              /* number of code lengths in lens[] */
+    code FAR *next;             /* next available space in codes[] */
+    unsigned short lens[320];   /* temporary storage for code lengths */
+    unsigned short work[288];   /* work area for code table building */
+    code codes[ENOUGH];         /* space for code tables */
+};
diff --git a/gs/zlib/contrib/infback9/inftree9.c b/gs/zlib/contrib/infback9/inftree9.c
new file mode 100644
index 000000000..0993f7564
--- /dev/null
+++ b/gs/zlib/contrib/infback9/inftree9.c
@@ -0,0 +1,323 @@
+/* inftree9.c -- generate Huffman trees for efficient decoding
+ * Copyright (C) 1995-2005 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#include "zutil.h"
+#include "inftree9.h"
+
+#define MAXBITS 15
+
+const char inflate9_copyright[] =
+   " inflate9 1.2.3 Copyright 1995-2005 Mark Adler ";
+/*
+  If you use the zlib library in a product, an acknowledgment is welcome
+  in the documentation of your product. If for some reason you cannot
+  include such an acknowledgment, I would appreciate that you keep this
+  copyright string in the executable of your product.
+ */
+
+/*
+   Build a set of tables to decode the provided canonical Huffman code.
+   The code lengths are lens[0..codes-1].  The result starts at *table,
+   whose indices are 0..2^bits-1.  work is a writable array of at least
+   lens shorts, which is used as a work area.  type is the type of code
+   to be generated, CODES, LENS, or DISTS.  On return, zero is success,
+   -1 is an invalid code, and +1 means that ENOUGH isn't enough.  table
+   on return points to the next available entry's address.  bits is the
+   requested root table index bits, and on return it is the actual root
+   table index bits.  It will differ if the request is greater than the
+   longest code or if it is less than the shortest code.
+ */
+int inflate_table9(type, lens, codes, table, bits, work)
+codetype type;
+unsigned short FAR *lens;
+unsigned codes;
+code FAR * FAR *table;
+unsigned FAR *bits;
+unsigned short FAR *work;
+{
+    unsigned len;               /* a code's length in bits */
+    unsigned sym;               /* index of code symbols */
+    unsigned min, max;          /* minimum and maximum code lengths */
+    unsigned root;              /* number of index bits for root table */
+    unsigned curr;              /* number of index bits for current table */
+    unsigned drop;              /* code bits to drop for sub-table */
+    int left;                   /* number of prefix codes available */
+    unsigned used;              /* code entries in table used */
+    unsigned huff;              /* Huffman code */
+    unsigned incr;              /* for incrementing code, index */
+    unsigned fill;              /* index for replicating entries */
+    unsigned low;               /* low bits for current root entry */
+    unsigned mask;              /* mask for low root bits */
+    code this;                  /* table entry for duplication */
+    code FAR *next;             /* next available space in table */
+    const unsigned short FAR *base;     /* base value table to use */
+    const unsigned short FAR *extra;    /* extra bits table to use */
+    int end;                    /* use base and extra for symbol > end */
+    unsigned short count[MAXBITS+1];    /* number of codes of each length */
+    unsigned short offs[MAXBITS+1];     /* offsets in table for each length */
+    static const unsigned short lbase[31] = { /* Length codes 257..285 base */
+        3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17,
+        19, 23, 27, 31, 35, 43, 51, 59, 67, 83, 99, 115,
+        131, 163, 195, 227, 3, 0, 0};
+    static const unsigned short lext[31] = { /* Length codes 257..285 extra */
+        128, 128, 128, 128, 128, 128, 128, 128, 129, 129, 129, 129,
+        130, 130, 130, 130, 131, 131, 131, 131, 132, 132, 132, 132,
+        133, 133, 133, 133, 144, 201, 196};
+    static const unsigned short dbase[32] = { /* Distance codes 0..31 base */
+        1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49,
+        65, 97, 129, 193, 257, 385, 513, 769, 1025, 1537, 2049, 3073,
+        4097, 6145, 8193, 12289, 16385, 24577, 32769, 49153};
+    static const unsigned short dext[32] = { /* Distance codes 0..31 extra */
+        128, 128, 128, 128, 129, 129, 130, 130, 131, 131, 132, 132,
+        133, 133, 134, 134, 135, 135, 136, 136, 137, 137, 138, 138,
+        139, 139, 140, 140, 141, 141, 142, 142};
+
+    /*
+       Process a set of code lengths to create a canonical Huffman code.  The
+       code lengths are lens[0..codes-1].  Each length corresponds to the
+       symbols 0..codes-1.  The Huffman code is generated by first sorting the
+       symbols by length from short to long, and retaining the symbol order
+       for codes with equal lengths.  Then the code starts with all zero bits
+       for the first code of the shortest length, and the codes are integer
+       increments for the same length, and zeros are appended as the length
+       increases.  For the deflate format, these bits are stored backwards
+       from their more natural integer increment ordering, and so when the
+       decoding tables are built in the large loop below, the integer codes
+       are incremented backwards.
+
+       This routine assumes, but does not check, that all of the entries in
+       lens[] are in the range 0..MAXBITS.  The caller must assure this.
+       1..MAXBITS is interpreted as that code length.  zero means that that
+       symbol does not occur in this code.
+
+       The codes are sorted by computing a count of codes for each length,
+       creating from that a table of starting indices for each length in the
+       sorted table, and then entering the symbols in order in the sorted
+       table.  The sorted table is work[], with that space being provided by
+       the caller.
+
+       The length counts are used for other purposes as well, i.e. finding
+       the minimum and maximum length codes, determining if there are any
+       codes at all, checking for a valid set of lengths, and looking ahead
+       at length counts to determine sub-table sizes when building the
+       decoding tables.
+     */
+
+    /* accumulate lengths for codes (assumes lens[] all in 0..MAXBITS) */
+    for (len = 0; len <= MAXBITS; len++)
+        count[len] = 0;
+    for (sym = 0; sym < codes; sym++)
+        count[lens[sym]]++;
+
+    /* bound code lengths, force root to be within code lengths */
+    root = *bits;
+    for (max = MAXBITS; max >= 1; max--)
+        if (count[max] != 0) break;
+    if (root > max) root = max;
+    if (max == 0) return -1;            /* no codes! */
+    for (min = 1; min <= MAXBITS; min++)
+        if (count[min] != 0) break;
+    if (root < min) root = min;
+
+    /* check for an over-subscribed or incomplete set of lengths */
+    left = 1;
+    for (len = 1; len <= MAXBITS; len++) {
+        left <<= 1;
+        left -= count[len];
+        if (left < 0) return -1;        /* over-subscribed */
+    }
+    if (left > 0 && (type == CODES || max != 1))
+        return -1;                      /* incomplete set */
+
+    /* generate offsets into symbol table for each length for sorting */
+    offs[1] = 0;
+    for (len = 1; len < MAXBITS; len++)
+        offs[len + 1] = offs[len] + count[len];
+
+    /* sort symbols by length, by symbol order within each length */
+    for (sym = 0; sym < codes; sym++)
+        if (lens[sym] != 0) work[offs[lens[sym]]++] = (unsigned short)sym;
+
+    /*
+       Create and fill in decoding tables.  In this loop, the table being
+       filled is at next and has curr index bits.  The code being used is huff
+       with length len.  That code is converted to an index by dropping drop
+       bits off of the bottom.  For codes where len is less than drop + curr,
+       those top drop + curr - len bits are incremented through all values to
+       fill the table with replicated entries.
+
+       root is the number of index bits for the root table.  When len exceeds
+       root, sub-tables are created pointed to by the root entry with an index
+       of the low root bits of huff.  This is saved in low to check for when a
+       new sub-table should be started.  drop is zero when the root table is
+       being filled, and drop is root when sub-tables are being filled.
+
+       When a new sub-table is needed, it is necessary to look ahead in the
+       code lengths to determine what size sub-table is needed.  The length
+       counts are used for this, and so count[] is decremented as codes are
+       entered in the tables.
+
+       used keeps track of how many table entries have been allocated from the
+       provided *table space.  It is checked when a LENS table is being made
+       against the space in *table, ENOUGH, minus the maximum space needed by
+       the worst case distance code, MAXD.  This should never happen, but the
+       sufficiency of ENOUGH has not been proven exhaustively, hence the check.
+       This assumes that when type == LENS, bits == 9.
+
+       sym increments through all symbols, and the loop terminates when
+       all codes of length max, i.e. all codes, have been processed.  This
+       routine permits incomplete codes, so another loop after this one fills
+       in the rest of the decoding tables with invalid code markers.
+     */
+
+    /* set up for code type */
+    switch (type) {
+    case CODES:
+        base = extra = work;    /* dummy value--not used */
+        end = 19;
+        break;
+    case LENS:
+        base = lbase;
+        base -= 257;
+        extra = lext;
+        extra -= 257;
+        end = 256;
+        break;
+    default:            /* DISTS */
+        base = dbase;
+        extra = dext;
+        end = -1;
+    }
+
+    /* initialize state for loop */
+    huff = 0;                   /* starting code */
+    sym = 0;                    /* starting code symbol */
+    len = min;                  /* starting code length */
+    next = *table;              /* current table to fill in */
+    curr = root;                /* current table index bits */
+    drop = 0;                   /* current bits to drop from code for index */
+    low = (unsigned)(-1);       /* trigger new sub-table when len > root */
+    used = 1U << root;          /* use root table entries */
+    mask = used - 1;            /* mask for comparing low */
+
+    /* check available table space */
+    if (type == LENS && used >= ENOUGH - MAXD)
+        return 1;
+
+    /* process all codes and make table entries */
+    for (;;) {
+        /* create table entry */
+        this.bits = (unsigned char)(len - drop);
+        if ((int)(work[sym]) < end) {
+            this.op = (unsigned char)0;
+            this.val = work[sym];
+        }
+        else if ((int)(work[sym]) > end) {
+            this.op = (unsigned char)(extra[work[sym]]);
+            this.val = base[work[sym]];
+        }
+        else {
+            this.op = (unsigned char)(32 + 64);         /* end of block */
+            this.val = 0;
+        }
+
+        /* replicate for those indices with low len bits equal to huff */
+        incr = 1U << (len - drop);
+        fill = 1U << curr;
+        do {
+            fill -= incr;
+            next[(huff >> drop) + fill] = this;
+        } while (fill != 0);
+
+        /* backwards increment the len-bit code huff */
+        incr = 1U << (len - 1);
+        while (huff & incr)
+            incr >>= 1;
+        if (incr != 0) {
+            huff &= incr - 1;
+            huff += incr;
+        }
+        else
+            huff = 0;
+
+        /* go to next symbol, update count, len */
+        sym++;
+        if (--(count[len]) == 0) {
+            if (len == max) break;
+            len = lens[work[sym]];
+        }
+
+        /* create new sub-table if needed */
+        if (len > root && (huff & mask) != low) {
+            /* if first time, transition to sub-tables */
+            if (drop == 0)
+                drop = root;
+
+            /* increment past last table */
+            next += 1U << curr;
+
+            /* determine length of next table */
+            curr = len - drop;
+            left = (int)(1 << curr);
+            while (curr + drop < max) {
+                left -= count[curr + drop];
+                if (left <= 0) break;
+                curr++;
+                left <<= 1;
+            }
+
+            /* check for enough space */
+            used += 1U << curr;
+            if (type == LENS && used >= ENOUGH - MAXD)
+                return 1;
+
+            /* point entry in root table to sub-table */
+            low = huff & mask;
+            (*table)[low].op = (unsigned char)curr;
+            (*table)[low].bits = (unsigned char)root;
+            (*table)[low].val = (unsigned short)(next - *table);
+        }
+    }
+
+    /*
+       Fill in rest of table for incomplete codes.  This loop is similar to the
+       loop above in incrementing huff for table indices.  It is assumed that
+       len is equal to curr + drop, so there is no loop needed to increment
+       through high index bits.  When the current sub-table is filled, the loop
+       drops back to the root table to fill in any remaining entries there.
+     */
+    this.op = (unsigned char)64;                /* invalid code marker */
+    this.bits = (unsigned char)(len - drop);
+    this.val = (unsigned short)0;
+    while (huff != 0) {
+        /* when done with sub-table, drop back to root table */
+        if (drop != 0 && (huff & mask) != low) {
+            drop = 0;
+            len = root;
+            next = *table;
+            curr = root;
+            this.bits = (unsigned char)len;
+        }
+
+        /* put invalid code marker in table */
+        next[huff >> drop] = this;
+
+        /* backwards increment the len-bit code huff */
+        incr = 1U << (len - 1);
+        while (huff & incr)
+            incr >>= 1;
+        if (incr != 0) {
+            huff &= incr - 1;
+            huff += incr;
+        }
+        else
+            huff = 0;
+    }
+
+    /* set return parameters */
+    *table += used;
+    *bits = root;
+    return 0;
+}
diff --git a/gs/zlib/contrib/infback9/inftree9.h b/gs/zlib/contrib/infback9/inftree9.h
new file mode 100644
index 000000000..a268084ee
--- /dev/null
+++ b/gs/zlib/contrib/infback9/inftree9.h
@@ -0,0 +1,55 @@
+/* inftree9.h -- header to use inftree9.c
+ * Copyright (C) 1995-2003 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* WARNING: this file should *not* be used by applications. It is
+   part of the implementation of the compression library and is
+   subject to change. Applications should only use zlib.h.
+ */
+
+/* Structure for decoding tables.  Each entry provides either the
+   information needed to do the operation requested by the code that
+   indexed that table entry, or it provides a pointer to another
+   table that indexes more bits of the code.  op indicates whether
+   the entry is a pointer to another table, a literal, a length or
+   distance, an end-of-block, or an invalid code.  For a table
+   pointer, the low four bits of op is the number of index bits of
+   that table.  For a length or distance, the low four bits of op
+   is the number of extra bits to get after the code.  bits is
+   the number of bits in this code or part of the code to drop off
+   of the bit buffer.  val is the actual byte to output in the case
+   of a literal, the base length or distance, or the offset from
+   the current table to the next table.  Each entry is four bytes. */
+typedef struct {
+    unsigned char op;           /* operation, extra bits, table bits */
+    unsigned char bits;         /* bits in this part of the code */
+    unsigned short val;         /* offset in table or code value */
+} code;
+
+/* op values as set by inflate_table():
+    00000000 - literal
+    0000tttt - table link, tttt != 0 is the number of table index bits
+    100eeeee - length or distance, eeee is the number of extra bits
+    01100000 - end of block
+    01000000 - invalid code
+ */
+
+/* Maximum size of dynamic tree.  The maximum found in a long but non-
+   exhaustive search was 1444 code structures (852 for length/literals
+   and 592 for distances, the latter actually the result of an
+   exhaustive search).  The true maximum is not known, but the value
+   below is more than safe. */
+#define ENOUGH 2048
+#define MAXD 592
+
+/* Type of code to build for inftable() */
+typedef enum {
+    CODES,
+    LENS,
+    DISTS
+} codetype;
+
+extern int inflate_table9 OF((codetype type, unsigned short FAR *lens,
+                             unsigned codes, code FAR * FAR *table,
+                             unsigned FAR *bits, unsigned short FAR *work));
diff --git a/gs/zlib/contrib/inflate86/inffas86.c b/gs/zlib/contrib/inflate86/inffas86.c
new file mode 100644
index 000000000..6da76358c
--- /dev/null
+++ b/gs/zlib/contrib/inflate86/inffas86.c
@@ -0,0 +1,1157 @@
+/* inffas86.c is a hand tuned assembler version of
+ *
+ * inffast.c -- fast decoding
+ * Copyright (C) 1995-2003 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ *
+ * Copyright (C) 2003 Chris Anderson <christop@charm.net>
+ * Please use the copyright conditions above.
+ *
+ * Dec-29-2003 -- I added AMD64 inflate asm support.  This version is also
+ * slightly quicker on x86 systems because, instead of using rep movsb to copy
+ * data, it uses rep movsw, which moves data in 2-byte chunks instead of single
+ * bytes.  I've tested the AMD64 code on a Fedora Core 1 + the x86_64 updates
+ * from http://fedora.linux.duke.edu/fc1_x86_64
+ * which is running on an Athlon 64 3000+ / Gigabyte GA-K8VT800M system with
+ * 1GB ram.  The 64-bit version is about 4% faster than the 32-bit version,
+ * when decompressing mozilla-source-1.3.tar.gz.
+ *
+ * Mar-13-2003 -- Most of this is derived from inffast.S which is derived from
+ * the gcc -S output of zlib-1.2.0/inffast.c.  Zlib-1.2.0 is in beta release at
+ * the moment.  I have successfully compiled and tested this code with gcc2.96,
+ * gcc3.2, icc5.0, msvc6.0.  It is very close to the speed of inffast.S
+ * compiled with gcc -DNO_MMX, but inffast.S is still faster on the P3 with MMX
+ * enabled.  I will attempt to merge the MMX code into this version.  Newer
+ * versions of this and inffast.S can be found at
+ * http://www.eetbeetee.com/zlib/ and http://www.charm.net/~christop/zlib/
+ */
+
+#include "zutil.h"
+#include "inftrees.h"
+#include "inflate.h"
+#include "inffast.h"
+
+/* Mark Adler's comments from inffast.c: */
+
+/*
+   Decode literal, length, and distance codes and write out the resulting
+   literal and match bytes until either not enough input or output is
+   available, an end-of-block is encountered, or a data error is encountered.
+   When large enough input and output buffers are supplied to inflate(), for
+   example, a 16K input buffer and a 64K output buffer, more than 95% of the
+   inflate execution time is spent in this routine.
+
+   Entry assumptions:
+
+        state->mode == LEN
+        strm->avail_in >= 6
+        strm->avail_out >= 258
+        start >= strm->avail_out
+        state->bits < 8
+
+   On return, state->mode is one of:
+
+        LEN -- ran out of enough output space or enough available input
+        TYPE -- reached end of block code, inflate() to interpret next block
+        BAD -- error in block data
+
+   Notes:
+
+    - The maximum input bits used by a length/distance pair is 15 bits for the
+      length code, 5 bits for the length extra, 15 bits for the distance code,
+      and 13 bits for the distance extra.  This totals 48 bits, or six bytes.
+      Therefore if strm->avail_in >= 6, then there is enough input to avoid
+      checking for available input while decoding.
+
+    - The maximum bytes that a single length/distance pair can output is 258
+      bytes, which is the maximum length that can be coded.  inflate_fast()
+      requires strm->avail_out >= 258 for each loop to avoid checking for
+      output space.
+ */
+void inflate_fast(strm, start)
+z_streamp strm;
+unsigned start;         /* inflate()'s starting value for strm->avail_out */
+{
+    struct inflate_state FAR *state;
+    struct inffast_ar {
+/* 64   32                               x86  x86_64 */
+/* ar offset                              register */
+/*  0    0 */ void *esp;                /* esp save */
+/*  8    4 */ void *ebp;                /* ebp save */
+/* 16    8 */ unsigned char FAR *in;    /* esi rsi  local strm->next_in */
+/* 24   12 */ unsigned char FAR *last;  /*     r9   while in < last */
+/* 32   16 */ unsigned char FAR *out;   /* edi rdi  local strm->next_out */
+/* 40   20 */ unsigned char FAR *beg;   /*          inflate()'s init next_out */
+/* 48   24 */ unsigned char FAR *end;   /*     r10  while out < end */
+/* 56   28 */ unsigned char FAR *window;/*          size of window, wsize!=0 */
+/* 64   32 */ code const FAR *lcode;    /* ebp rbp  local strm->lencode */
+/* 72   36 */ code const FAR *dcode;    /*     r11  local strm->distcode */
+/* 80   40 */ unsigned long hold;       /* edx rdx  local strm->hold */
+/* 88   44 */ unsigned bits;            /* ebx rbx  local strm->bits */
+/* 92   48 */ unsigned wsize;           /*          window size */
+/* 96   52 */ unsigned write;           /*          window write index */
+/*100   56 */ unsigned lmask;           /*     r12  mask for lcode */
+/*104   60 */ unsigned dmask;           /*     r13  mask for dcode */
+/*108   64 */ unsigned len;             /*     r14  match length */
+/*112   68 */ unsigned dist;            /*     r15  match distance */
+/*116   72 */ unsigned status;          /*          set when state chng*/
+    } ar;
+
+#if defined( __GNUC__ ) && defined( __amd64__ ) && ! defined( __i386 )
+#define PAD_AVAIL_IN 6
+#define PAD_AVAIL_OUT 258
+#else
+#define PAD_AVAIL_IN 5
+#define PAD_AVAIL_OUT 257
+#endif
+
+    /* copy state to local variables */
+    state = (struct inflate_state FAR *)strm->state;
+    ar.in = strm->next_in;
+    ar.last = ar.in + (strm->avail_in - PAD_AVAIL_IN);
+    ar.out = strm->next_out;
+    ar.beg = ar.out - (start - strm->avail_out);
+    ar.end = ar.out + (strm->avail_out - PAD_AVAIL_OUT);
+    ar.wsize = state->wsize;
+    ar.write = state->write;
+    ar.window = state->window;
+    ar.hold = state->hold;
+    ar.bits = state->bits;
+    ar.lcode = state->lencode;
+    ar.dcode = state->distcode;
+    ar.lmask = (1U << state->lenbits) - 1;
+    ar.dmask = (1U << state->distbits) - 1;
+
+    /* decode literals and length/distances until end-of-block or not enough
+       input data or output space */
+
+    /* align in on 1/2 hold size boundary */
+    while (((unsigned long)(void *)ar.in & (sizeof(ar.hold) / 2 - 1)) != 0) {
+        ar.hold += (unsigned long)*ar.in++ << ar.bits;
+        ar.bits += 8;
+    }
+
+#if defined( __GNUC__ ) && defined( __amd64__ ) && ! defined( __i386 )
+    __asm__ __volatile__ (
+"        leaq    %0, %%rax\n"
+"        movq    %%rbp, 8(%%rax)\n"       /* save regs rbp and rsp */
+"        movq    %%rsp, (%%rax)\n"
+"        movq    %%rax, %%rsp\n"          /* make rsp point to &ar */
+"        movq    16(%%rsp), %%rsi\n"      /* rsi  = in */
+"        movq    32(%%rsp), %%rdi\n"      /* rdi  = out */
+"        movq    24(%%rsp), %%r9\n"       /* r9   = last */
+"        movq    48(%%rsp), %%r10\n"      /* r10  = end */
+"        movq    64(%%rsp), %%rbp\n"      /* rbp  = lcode */
+"        movq    72(%%rsp), %%r11\n"      /* r11  = dcode */
+"        movq    80(%%rsp), %%rdx\n"      /* rdx  = hold */
+"        movl    88(%%rsp), %%ebx\n"      /* ebx  = bits */
+"        movl    100(%%rsp), %%r12d\n"    /* r12d = lmask */
+"        movl    104(%%rsp), %%r13d\n"    /* r13d = dmask */
+                                          /* r14d = len */
+                                          /* r15d = dist */
+"        cld\n"
+"        cmpq    %%rdi, %%r10\n"
+"        je      .L_one_time\n"           /* if only one decode left */
+"        cmpq    %%rsi, %%r9\n"
+"        je      .L_one_time\n"
+"        jmp     .L_do_loop\n"
+
+".L_one_time:\n"
+"        movq    %%r12, %%r8\n"           /* r8 = lmask */
+"        cmpb    $32, %%bl\n"
+"        ja      .L_get_length_code_one_time\n"
+
+"        lodsl\n"                         /* eax = *(uint *)in++ */
+"        movb    %%bl, %%cl\n"            /* cl = bits, needs it for shifting */
+"        addb    $32, %%bl\n"             /* bits += 32 */
+"        shlq    %%cl, %%rax\n"
+"        orq     %%rax, %%rdx\n"          /* hold |= *((uint *)in)++ << bits */
+"        jmp     .L_get_length_code_one_time\n"
+
+".align 32,0x90\n"
+".L_while_test:\n"
+"        cmpq    %%rdi, %%r10\n"
+"        jbe     .L_break_loop\n"
+"        cmpq    %%rsi, %%r9\n"
+"        jbe     .L_break_loop\n"
+
+".L_do_loop:\n"
+"        movq    %%r12, %%r8\n"           /* r8 = lmask */
+"        cmpb    $32, %%bl\n"
+"        ja      .L_get_length_code\n"    /* if (32 < bits) */
+
+"        lodsl\n"                         /* eax = *(uint *)in++ */
+"        movb    %%bl, %%cl\n"            /* cl = bits, needs it for shifting */
+"        addb    $32, %%bl\n"             /* bits += 32 */
+"        shlq    %%cl, %%rax\n"
+"        orq     %%rax, %%rdx\n"          /* hold |= *((uint *)in)++ << bits */
+
+".L_get_length_code:\n"
+"        andq    %%rdx, %%r8\n"            /* r8 &= hold */
+"        movl    (%%rbp,%%r8,4), %%eax\n"  /* eax = lcode[hold & lmask] */
+
+"        movb    %%ah, %%cl\n"            /* cl = this.bits */
+"        subb    %%ah, %%bl\n"            /* bits -= this.bits */
+"        shrq    %%cl, %%rdx\n"           /* hold >>= this.bits */
+
+"        testb   %%al, %%al\n"
+"        jnz     .L_test_for_length_base\n" /* if (op != 0) 45.7% */
+
+"        movq    %%r12, %%r8\n"            /* r8 = lmask */
+"        shrl    $16, %%eax\n"            /* output this.val char */
+"        stosb\n"
+
+".L_get_length_code_one_time:\n"
+"        andq    %%rdx, %%r8\n"            /* r8 &= hold */
+"        movl    (%%rbp,%%r8,4), %%eax\n" /* eax = lcode[hold & lmask] */
+
+".L_dolen:\n"
+"        movb    %%ah, %%cl\n"            /* cl = this.bits */
+"        subb    %%ah, %%bl\n"            /* bits -= this.bits */
+"        shrq    %%cl, %%rdx\n"           /* hold >>= this.bits */
+
+"        testb   %%al, %%al\n"
+"        jnz     .L_test_for_length_base\n" /* if (op != 0) 45.7% */
+
+"        shrl    $16, %%eax\n"            /* output this.val char */
+"        stosb\n"
+"        jmp     .L_while_test\n"
+
+".align 32,0x90\n"
+".L_test_for_length_base:\n"
+"        movl    %%eax, %%r14d\n"         /* len = this */
+"        shrl    $16, %%r14d\n"           /* len = this.val */
+"        movb    %%al, %%cl\n"
+
+"        testb   $16, %%al\n"
+"        jz      .L_test_for_second_level_length\n" /* if ((op & 16) == 0) 8% */
+"        andb    $15, %%cl\n"             /* op &= 15 */
+"        jz      .L_decode_distance\n"    /* if (!op) */
+
+".L_add_bits_to_len:\n"
+"        subb    %%cl, %%bl\n"
+"        xorl    %%eax, %%eax\n"
+"        incl    %%eax\n"
+"        shll    %%cl, %%eax\n"
+"        decl    %%eax\n"
+"        andl    %%edx, %%eax\n"          /* eax &= hold */
+"        shrq    %%cl, %%rdx\n"
+"        addl    %%eax, %%r14d\n"         /* len += hold & mask[op] */
+
+".L_decode_distance:\n"
+"        movq    %%r13, %%r8\n"           /* r8 = dmask */
+"        cmpb    $32, %%bl\n"
+"        ja      .L_get_distance_code\n"  /* if (32 < bits) */
+
+"        lodsl\n"                         /* eax = *(uint *)in++ */
+"        movb    %%bl, %%cl\n"            /* cl = bits, needs it for shifting */
+"        addb    $32, %%bl\n"             /* bits += 32 */
+"        shlq    %%cl, %%rax\n"
+"        orq     %%rax, %%rdx\n"          /* hold |= *((uint *)in)++ << bits */
+
+".L_get_distance_code:\n"
+"        andq    %%rdx, %%r8\n"           /* r8 &= hold */
+"        movl    (%%r11,%%r8,4), %%eax\n" /* eax = dcode[hold & dmask] */
+
+".L_dodist:\n"
+"        movl    %%eax, %%r15d\n"         /* dist = this */
+"        shrl    $16, %%r15d\n"           /* dist = this.val */
+"        movb    %%ah, %%cl\n"
+"        subb    %%ah, %%bl\n"            /* bits -= this.bits */
+"        shrq    %%cl, %%rdx\n"           /* hold >>= this.bits */
+"        movb    %%al, %%cl\n"            /* cl = this.op */
+
+"        testb   $16, %%al\n"             /* if ((op & 16) == 0) */
+"        jz      .L_test_for_second_level_dist\n"
+"        andb    $15, %%cl\n"             /* op &= 15 */
+"        jz      .L_check_dist_one\n"
+
+".L_add_bits_to_dist:\n"
+"        subb    %%cl, %%bl\n"
+"        xorl    %%eax, %%eax\n"
+"        incl    %%eax\n"
+"        shll    %%cl, %%eax\n"
+"        decl    %%eax\n"                 /* (1 << op) - 1 */
+"        andl    %%edx, %%eax\n"          /* eax &= hold */
+"        shrq    %%cl, %%rdx\n"
+"        addl    %%eax, %%r15d\n"         /* dist += hold & ((1 << op) - 1) */
+
+".L_check_window:\n"
+"        movq    %%rsi, %%r8\n"           /* save in so from can use it's reg */
+"        movq    %%rdi, %%rax\n"
+"        subq    40(%%rsp), %%rax\n"      /* nbytes = out - beg */
+
+"        cmpl    %%r15d, %%eax\n"
+"        jb      .L_clip_window\n"        /* if (dist > nbytes) 4.2% */
+
+"        movl    %%r14d, %%ecx\n"         /* ecx = len */
+"        movq    %%rdi, %%rsi\n"
+"        subq    %%r15, %%rsi\n"          /* from = out - dist */
+
+"        sarl    %%ecx\n"
+"        jnc     .L_copy_two\n"           /* if len % 2 == 0 */
+
+"        rep     movsw\n"
+"        movb    (%%rsi), %%al\n"
+"        movb    %%al, (%%rdi)\n"
+"        incq    %%rdi\n"
+
+"        movq    %%r8, %%rsi\n"           /* move in back to %rsi, toss from */
+"        jmp     .L_while_test\n"
+
+".L_copy_two:\n"
+"        rep     movsw\n"
+"        movq    %%r8, %%rsi\n"           /* move in back to %rsi, toss from */
+"        jmp     .L_while_test\n"
+
+".align 32,0x90\n"
+".L_check_dist_one:\n"
+"        cmpl    $1, %%r15d\n"            /* if dist 1, is a memset */
+"        jne     .L_check_window\n"
+"        cmpq    %%rdi, 40(%%rsp)\n"      /* if out == beg, outside window */
+"        je      .L_check_window\n"
+
+"        movl    %%r14d, %%ecx\n"         /* ecx = len */
+"        movb    -1(%%rdi), %%al\n"
+"        movb    %%al, %%ah\n"
+
+"        sarl    %%ecx\n"
+"        jnc     .L_set_two\n"
+"        movb    %%al, (%%rdi)\n"
+"        incq    %%rdi\n"
+
+".L_set_two:\n"
+"        rep     stosw\n"
+"        jmp     .L_while_test\n"
+
+".align 32,0x90\n"
+".L_test_for_second_level_length:\n"
+"        testb   $64, %%al\n"
+"        jnz     .L_test_for_end_of_block\n" /* if ((op & 64) != 0) */
+
+"        xorl    %%eax, %%eax\n"
+"        incl    %%eax\n"
+"        shll    %%cl, %%eax\n"
+"        decl    %%eax\n"
+"        andl    %%edx, %%eax\n"         /* eax &= hold */
+"        addl    %%r14d, %%eax\n"        /* eax += len */
+"        movl    (%%rbp,%%rax,4), %%eax\n" /* eax = lcode[val+(hold&mask[op])]*/
+"        jmp     .L_dolen\n"
+
+".align 32,0x90\n"
+".L_test_for_second_level_dist:\n"
+"        testb   $64, %%al\n"
+"        jnz     .L_invalid_distance_code\n" /* if ((op & 64) != 0) */
+
+"        xorl    %%eax, %%eax\n"
+"        incl    %%eax\n"
+"        shll    %%cl, %%eax\n"
+"        decl    %%eax\n"
+"        andl    %%edx, %%eax\n"         /* eax &= hold */
+"        addl    %%r15d, %%eax\n"        /* eax += dist */
+"        movl    (%%r11,%%rax,4), %%eax\n" /* eax = dcode[val+(hold&mask[op])]*/
+"        jmp     .L_dodist\n"
+
+".align 32,0x90\n"
+".L_clip_window:\n"
+"        movl    %%eax, %%ecx\n"         /* ecx = nbytes */
+"        movl    92(%%rsp), %%eax\n"     /* eax = wsize, prepare for dist cmp */
+"        negl    %%ecx\n"                /* nbytes = -nbytes */
+
+"        cmpl    %%r15d, %%eax\n"
+"        jb      .L_invalid_distance_too_far\n" /* if (dist > wsize) */
+
+"        addl    %%r15d, %%ecx\n"         /* nbytes = dist - nbytes */
+"        cmpl    $0, 96(%%rsp)\n"
+"        jne     .L_wrap_around_window\n" /* if (write != 0) */
+
+"        movq    56(%%rsp), %%rsi\n"     /* from  = window */
+"        subl    %%ecx, %%eax\n"         /* eax  -= nbytes */
+"        addq    %%rax, %%rsi\n"         /* from += wsize - nbytes */
+
+"        movl    %%r14d, %%eax\n"        /* eax = len */
+"        cmpl    %%ecx, %%r14d\n"
+"        jbe     .L_do_copy\n"           /* if (nbytes >= len) */
+
+"        subl    %%ecx, %%eax\n"         /* eax -= nbytes */
+"        rep     movsb\n"
+"        movq    %%rdi, %%rsi\n"
+"        subq    %%r15, %%rsi\n"         /* from = &out[ -dist ] */
+"        jmp     .L_do_copy\n"
+
+".align 32,0x90\n"
+".L_wrap_around_window:\n"
+"        movl    96(%%rsp), %%eax\n"     /* eax = write */
+"        cmpl    %%eax, %%ecx\n"
+"        jbe     .L_contiguous_in_window\n" /* if (write >= nbytes) */
+
+"        movl    92(%%rsp), %%esi\n"     /* from  = wsize */
+"        addq    56(%%rsp), %%rsi\n"     /* from += window */
+"        addq    %%rax, %%rsi\n"         /* from += write */
+"        subq    %%rcx, %%rsi\n"         /* from -= nbytes */
+"        subl    %%eax, %%ecx\n"         /* nbytes -= write */
+
+"        movl    %%r14d, %%eax\n"        /* eax = len */
+"        cmpl    %%ecx, %%eax\n"
+"        jbe     .L_do_copy\n"           /* if (nbytes >= len) */
+
+"        subl    %%ecx, %%eax\n"         /* len -= nbytes */
+"        rep     movsb\n"
+"        movq    56(%%rsp), %%rsi\n"     /* from = window */
+"        movl    96(%%rsp), %%ecx\n"     /* nbytes = write */
+"        cmpl    %%ecx, %%eax\n"
+"        jbe     .L_do_copy\n"           /* if (nbytes >= len) */
+
+"        subl    %%ecx, %%eax\n"         /* len -= nbytes */
+"        rep     movsb\n"
+"        movq    %%rdi, %%rsi\n"
+"        subq    %%r15, %%rsi\n"         /* from = out - dist */
+"        jmp     .L_do_copy\n"
+
+".align 32,0x90\n"
+".L_contiguous_in_window:\n"
+"        movq    56(%%rsp), %%rsi\n"     /* rsi = window */
+"        addq    %%rax, %%rsi\n"
+"        subq    %%rcx, %%rsi\n"         /* from += write - nbytes */
+
+"        movl    %%r14d, %%eax\n"        /* eax = len */
+"        cmpl    %%ecx, %%eax\n"
+"        jbe     .L_do_copy\n"           /* if (nbytes >= len) */
+
+"        subl    %%ecx, %%eax\n"         /* len -= nbytes */
+"        rep     movsb\n"
+"        movq    %%rdi, %%rsi\n"
+"        subq    %%r15, %%rsi\n"         /* from = out - dist */
+"        jmp     .L_do_copy\n"           /* if (nbytes >= len) */
+
+".align 32,0x90\n"
+".L_do_copy:\n"
+"        movl    %%eax, %%ecx\n"         /* ecx = len */
+"        rep     movsb\n"
+
+"        movq    %%r8, %%rsi\n"          /* move in back to %esi, toss from */
+"        jmp     .L_while_test\n"
+
+".L_test_for_end_of_block:\n"
+"        testb   $32, %%al\n"
+"        jz      .L_invalid_literal_length_code\n"
+"        movl    $1, 116(%%rsp)\n"
+"        jmp     .L_break_loop_with_status\n"
+
+".L_invalid_literal_length_code:\n"
+"        movl    $2, 116(%%rsp)\n"
+"        jmp     .L_break_loop_with_status\n"
+
+".L_invalid_distance_code:\n"
+"        movl    $3, 116(%%rsp)\n"
+"        jmp     .L_break_loop_with_status\n"
+
+".L_invalid_distance_too_far:\n"
+"        movl    $4, 116(%%rsp)\n"
+"        jmp     .L_break_loop_with_status\n"
+
+".L_break_loop:\n"
+"        movl    $0, 116(%%rsp)\n"
+
+".L_break_loop_with_status:\n"
+/* put in, out, bits, and hold back into ar and pop esp */
+"        movq    %%rsi, 16(%%rsp)\n"     /* in */
+"        movq    %%rdi, 32(%%rsp)\n"     /* out */
+"        movl    %%ebx, 88(%%rsp)\n"     /* bits */
+"        movq    %%rdx, 80(%%rsp)\n"     /* hold */
+"        movq    (%%rsp), %%rax\n"       /* restore rbp and rsp */
+"        movq    8(%%rsp), %%rbp\n"
+"        movq    %%rax, %%rsp\n"
+          :
+          : "m" (ar)
+          : "memory", "%rax", "%rbx", "%rcx", "%rdx", "%rsi", "%rdi",
+            "%r8", "%r9", "%r10", "%r11", "%r12", "%r13", "%r14", "%r15"
+    );
+#elif ( defined( __GNUC__ ) || defined( __ICC ) ) && defined( __i386 )
+    __asm__ __volatile__ (
+"        leal    %0, %%eax\n"
+"        movl    %%esp, (%%eax)\n"        /* save esp, ebp */
+"        movl    %%ebp, 4(%%eax)\n"
+"        movl    %%eax, %%esp\n"
+"        movl    8(%%esp), %%esi\n"       /* esi = in */
+"        movl    16(%%esp), %%edi\n"      /* edi = out */
+"        movl    40(%%esp), %%edx\n"      /* edx = hold */
+"        movl    44(%%esp), %%ebx\n"      /* ebx = bits */
+"        movl    32(%%esp), %%ebp\n"      /* ebp = lcode */
+
+"        cld\n"
+"        jmp     .L_do_loop\n"
+
+".align 32,0x90\n"
+".L_while_test:\n"
+"        cmpl    %%edi, 24(%%esp)\n"      /* out < end */
+"        jbe     .L_break_loop\n"
+"        cmpl    %%esi, 12(%%esp)\n"      /* in < last */
+"        jbe     .L_break_loop\n"
+
+".L_do_loop:\n"
+"        cmpb    $15, %%bl\n"
+"        ja      .L_get_length_code\n"    /* if (15 < bits) */
+
+"        xorl    %%eax, %%eax\n"
+"        lodsw\n"                         /* al = *(ushort *)in++ */
+"        movb    %%bl, %%cl\n"            /* cl = bits, needs it for shifting */
+"        addb    $16, %%bl\n"             /* bits += 16 */
+"        shll    %%cl, %%eax\n"
+"        orl     %%eax, %%edx\n"        /* hold |= *((ushort *)in)++ << bits */
+
+".L_get_length_code:\n"
+"        movl    56(%%esp), %%eax\n"      /* eax = lmask */
+"        andl    %%edx, %%eax\n"          /* eax &= hold */
+"        movl    (%%ebp,%%eax,4), %%eax\n" /* eax = lcode[hold & lmask] */
+
+".L_dolen:\n"
+"        movb    %%ah, %%cl\n"            /* cl = this.bits */
+"        subb    %%ah, %%bl\n"            /* bits -= this.bits */
+"        shrl    %%cl, %%edx\n"           /* hold >>= this.bits */
+
+"        testb   %%al, %%al\n"
+"        jnz     .L_test_for_length_base\n" /* if (op != 0) 45.7% */
+
+"        shrl    $16, %%eax\n"            /* output this.val char */
+"        stosb\n"
+"        jmp     .L_while_test\n"
+
+".align 32,0x90\n"
+".L_test_for_length_base:\n"
+"        movl    %%eax, %%ecx\n"          /* len = this */
+"        shrl    $16, %%ecx\n"            /* len = this.val */
+"        movl    %%ecx, 64(%%esp)\n"      /* save len */
+"        movb    %%al, %%cl\n"
+
+"        testb   $16, %%al\n"
+"        jz      .L_test_for_second_level_length\n" /* if ((op & 16) == 0) 8% */
+"        andb    $15, %%cl\n"             /* op &= 15 */
+"        jz      .L_decode_distance\n"    /* if (!op) */
+"        cmpb    %%cl, %%bl\n"
+"        jae     .L_add_bits_to_len\n"    /* if (op <= bits) */
+
+"        movb    %%cl, %%ch\n"            /* stash op in ch, freeing cl */
+"        xorl    %%eax, %%eax\n"
+"        lodsw\n"                         /* al = *(ushort *)in++ */
+"        movb    %%bl, %%cl\n"            /* cl = bits, needs it for shifting */
+"        addb    $16, %%bl\n"             /* bits += 16 */
+"        shll    %%cl, %%eax\n"
+"        orl     %%eax, %%edx\n"         /* hold |= *((ushort *)in)++ << bits */
+"        movb    %%ch, %%cl\n"            /* move op back to ecx */
+
+".L_add_bits_to_len:\n"
+"        subb    %%cl, %%bl\n"
+"        xorl    %%eax, %%eax\n"
+"        incl    %%eax\n"
+"        shll    %%cl, %%eax\n"
+"        decl    %%eax\n"
+"        andl    %%edx, %%eax\n"          /* eax &= hold */
+"        shrl    %%cl, %%edx\n"
+"        addl    %%eax, 64(%%esp)\n"      /* len += hold & mask[op] */
+
+".L_decode_distance:\n"
+"        cmpb    $15, %%bl\n"
+"        ja      .L_get_distance_code\n"  /* if (15 < bits) */
+
+"        xorl    %%eax, %%eax\n"
+"        lodsw\n"                         /* al = *(ushort *)in++ */
+"        movb    %%bl, %%cl\n"            /* cl = bits, needs it for shifting */
+"        addb    $16, %%bl\n"             /* bits += 16 */
+"        shll    %%cl, %%eax\n"
+"        orl     %%eax, %%edx\n"         /* hold |= *((ushort *)in)++ << bits */
+
+".L_get_distance_code:\n"
+"        movl    60(%%esp), %%eax\n"      /* eax = dmask */
+"        movl    36(%%esp), %%ecx\n"      /* ecx = dcode */
+"        andl    %%edx, %%eax\n"          /* eax &= hold */
+"        movl    (%%ecx,%%eax,4), %%eax\n"/* eax = dcode[hold & dmask] */
+
+".L_dodist:\n"
+"        movl    %%eax, %%ebp\n"          /* dist = this */
+"        shrl    $16, %%ebp\n"            /* dist = this.val */
+"        movb    %%ah, %%cl\n"
+"        subb    %%ah, %%bl\n"            /* bits -= this.bits */
+"        shrl    %%cl, %%edx\n"           /* hold >>= this.bits */
+"        movb    %%al, %%cl\n"            /* cl = this.op */
+
+"        testb   $16, %%al\n"             /* if ((op & 16) == 0) */
+"        jz      .L_test_for_second_level_dist\n"
+"        andb    $15, %%cl\n"             /* op &= 15 */
+"        jz      .L_check_dist_one\n"
+"        cmpb    %%cl, %%bl\n"
+"        jae     .L_add_bits_to_dist\n"   /* if (op <= bits) 97.6% */
+
+"        movb    %%cl, %%ch\n"            /* stash op in ch, freeing cl */
+"        xorl    %%eax, %%eax\n"
+"        lodsw\n"                         /* al = *(ushort *)in++ */
+"        movb    %%bl, %%cl\n"            /* cl = bits, needs it for shifting */
+"        addb    $16, %%bl\n"             /* bits += 16 */
+"        shll    %%cl, %%eax\n"
+"        orl     %%eax, %%edx\n"        /* hold |= *((ushort *)in)++ << bits */
+"        movb    %%ch, %%cl\n"            /* move op back to ecx */
+
+".L_add_bits_to_dist:\n"
+"        subb    %%cl, %%bl\n"
+"        xorl    %%eax, %%eax\n"
+"        incl    %%eax\n"
+"        shll    %%cl, %%eax\n"
+"        decl    %%eax\n"                 /* (1 << op) - 1 */
+"        andl    %%edx, %%eax\n"          /* eax &= hold */
+"        shrl    %%cl, %%edx\n"
+"        addl    %%eax, %%ebp\n"          /* dist += hold & ((1 << op) - 1) */
+
+".L_check_window:\n"
+"        movl    %%esi, 8(%%esp)\n"       /* save in so from can use it's reg */
+"        movl    %%edi, %%eax\n"
+"        subl    20(%%esp), %%eax\n"      /* nbytes = out - beg */
+
+"        cmpl    %%ebp, %%eax\n"
+"        jb      .L_clip_window\n"        /* if (dist > nbytes) 4.2% */
+
+"        movl    64(%%esp), %%ecx\n"      /* ecx = len */
+"        movl    %%edi, %%esi\n"
+"        subl    %%ebp, %%esi\n"          /* from = out - dist */
+
+"        sarl    %%ecx\n"
+"        jnc     .L_copy_two\n"           /* if len % 2 == 0 */
+
+"        rep     movsw\n"
+"        movb    (%%esi), %%al\n"
+"        movb    %%al, (%%edi)\n"
+"        incl    %%edi\n"
+
+"        movl    8(%%esp), %%esi\n"       /* move in back to %esi, toss from */
+"        movl    32(%%esp), %%ebp\n"      /* ebp = lcode */
+"        jmp     .L_while_test\n"
+
+".L_copy_two:\n"
+"        rep     movsw\n"
+"        movl    8(%%esp), %%esi\n"       /* move in back to %esi, toss from */
+"        movl    32(%%esp), %%ebp\n"      /* ebp = lcode */
+"        jmp     .L_while_test\n"
+
+".align 32,0x90\n"
+".L_check_dist_one:\n"
+"        cmpl    $1, %%ebp\n"            /* if dist 1, is a memset */
+"        jne     .L_check_window\n"
+"        cmpl    %%edi, 20(%%esp)\n"
+"        je      .L_check_window\n"      /* out == beg, if outside window */
+
+"        movl    64(%%esp), %%ecx\n"      /* ecx = len */
+"        movb    -1(%%edi), %%al\n"
+"        movb    %%al, %%ah\n"
+
+"        sarl    %%ecx\n"
+"        jnc     .L_set_two\n"
+"        movb    %%al, (%%edi)\n"
+"        incl    %%edi\n"
+
+".L_set_two:\n"
+"        rep     stosw\n"
+"        movl    32(%%esp), %%ebp\n"      /* ebp = lcode */
+"        jmp     .L_while_test\n"
+
+".align 32,0x90\n"
+".L_test_for_second_level_length:\n"
+"        testb   $64, %%al\n"
+"        jnz     .L_test_for_end_of_block\n" /* if ((op & 64) != 0) */
+
+"        xorl    %%eax, %%eax\n"
+"        incl    %%eax\n"
+"        shll    %%cl, %%eax\n"
+"        decl    %%eax\n"
+"        andl    %%edx, %%eax\n"         /* eax &= hold */
+"        addl    64(%%esp), %%eax\n"     /* eax += len */
+"        movl    (%%ebp,%%eax,4), %%eax\n" /* eax = lcode[val+(hold&mask[op])]*/
+"        jmp     .L_dolen\n"
+
+".align 32,0x90\n"
+".L_test_for_second_level_dist:\n"
+"        testb   $64, %%al\n"
+"        jnz     .L_invalid_distance_code\n" /* if ((op & 64) != 0) */
+
+"        xorl    %%eax, %%eax\n"
+"        incl    %%eax\n"
+"        shll    %%cl, %%eax\n"
+"        decl    %%eax\n"
+"        andl    %%edx, %%eax\n"         /* eax &= hold */
+"        addl    %%ebp, %%eax\n"         /* eax += dist */
+"        movl    36(%%esp), %%ecx\n"     /* ecx = dcode */
+"        movl    (%%ecx,%%eax,4), %%eax\n" /* eax = dcode[val+(hold&mask[op])]*/
+"        jmp     .L_dodist\n"
+
+".align 32,0x90\n"
+".L_clip_window:\n"
+"        movl    %%eax, %%ecx\n"
+"        movl    48(%%esp), %%eax\n"     /* eax = wsize */
+"        negl    %%ecx\n"                /* nbytes = -nbytes */
+"        movl    28(%%esp), %%esi\n"     /* from = window */
+
+"        cmpl    %%ebp, %%eax\n"
+"        jb      .L_invalid_distance_too_far\n" /* if (dist > wsize) */
+
+"        addl    %%ebp, %%ecx\n"         /* nbytes = dist - nbytes */
+"        cmpl    $0, 52(%%esp)\n"
+"        jne     .L_wrap_around_window\n" /* if (write != 0) */
+
+"        subl    %%ecx, %%eax\n"
+"        addl    %%eax, %%esi\n"         /* from += wsize - nbytes */
+
+"        movl    64(%%esp), %%eax\n"     /* eax = len */
+"        cmpl    %%ecx, %%eax\n"
+"        jbe     .L_do_copy\n"           /* if (nbytes >= len) */
+
+"        subl    %%ecx, %%eax\n"         /* len -= nbytes */
+"        rep     movsb\n"
+"        movl    %%edi, %%esi\n"
+"        subl    %%ebp, %%esi\n"         /* from = out - dist */
+"        jmp     .L_do_copy\n"
+
+".align 32,0x90\n"
+".L_wrap_around_window:\n"
+"        movl    52(%%esp), %%eax\n"     /* eax = write */
+"        cmpl    %%eax, %%ecx\n"
+"        jbe     .L_contiguous_in_window\n" /* if (write >= nbytes) */
+
+"        addl    48(%%esp), %%esi\n"     /* from += wsize */
+"        addl    %%eax, %%esi\n"         /* from += write */
+"        subl    %%ecx, %%esi\n"         /* from -= nbytes */
+"        subl    %%eax, %%ecx\n"         /* nbytes -= write */
+
+"        movl    64(%%esp), %%eax\n"     /* eax = len */
+"        cmpl    %%ecx, %%eax\n"
+"        jbe     .L_do_copy\n"           /* if (nbytes >= len) */
+
+"        subl    %%ecx, %%eax\n"         /* len -= nbytes */
+"        rep     movsb\n"
+"        movl    28(%%esp), %%esi\n"     /* from = window */
+"        movl    52(%%esp), %%ecx\n"     /* nbytes = write */
+"        cmpl    %%ecx, %%eax\n"
+"        jbe     .L_do_copy\n"           /* if (nbytes >= len) */
+
+"        subl    %%ecx, %%eax\n"         /* len -= nbytes */
+"        rep     movsb\n"
+"        movl    %%edi, %%esi\n"
+"        subl    %%ebp, %%esi\n"         /* from = out - dist */
+"        jmp     .L_do_copy\n"
+
+".align 32,0x90\n"
+".L_contiguous_in_window:\n"
+"        addl    %%eax, %%esi\n"
+"        subl    %%ecx, %%esi\n"         /* from += write - nbytes */
+
+"        movl    64(%%esp), %%eax\n"     /* eax = len */
+"        cmpl    %%ecx, %%eax\n"
+"        jbe     .L_do_copy\n"           /* if (nbytes >= len) */
+
+"        subl    %%ecx, %%eax\n"         /* len -= nbytes */
+"        rep     movsb\n"
+"        movl    %%edi, %%esi\n"
+"        subl    %%ebp, %%esi\n"         /* from = out - dist */
+"        jmp     .L_do_copy\n"           /* if (nbytes >= len) */
+
+".align 32,0x90\n"
+".L_do_copy:\n"
+"        movl    %%eax, %%ecx\n"
+"        rep     movsb\n"
+
+"        movl    8(%%esp), %%esi\n"      /* move in back to %esi, toss from */
+"        movl    32(%%esp), %%ebp\n"     /* ebp = lcode */
+"        jmp     .L_while_test\n"
+
+".L_test_for_end_of_block:\n"
+"        testb   $32, %%al\n"
+"        jz      .L_invalid_literal_length_code\n"
+"        movl    $1, 72(%%esp)\n"
+"        jmp     .L_break_loop_with_status\n"
+
+".L_invalid_literal_length_code:\n"
+"        movl    $2, 72(%%esp)\n"
+"        jmp     .L_break_loop_with_status\n"
+
+".L_invalid_distance_code:\n"
+"        movl    $3, 72(%%esp)\n"
+"        jmp     .L_break_loop_with_status\n"
+
+".L_invalid_distance_too_far:\n"
+"        movl    8(%%esp), %%esi\n"
+"        movl    $4, 72(%%esp)\n"
+"        jmp     .L_break_loop_with_status\n"
+
+".L_break_loop:\n"
+"        movl    $0, 72(%%esp)\n"
+
+".L_break_loop_with_status:\n"
+/* put in, out, bits, and hold back into ar and pop esp */
+"        movl    %%esi, 8(%%esp)\n"      /* save in */
+"        movl    %%edi, 16(%%esp)\n"     /* save out */
+"        movl    %%ebx, 44(%%esp)\n"     /* save bits */
+"        movl    %%edx, 40(%%esp)\n"     /* save hold */
+"        movl    4(%%esp), %%ebp\n"      /* restore esp, ebp */
+"        movl    (%%esp), %%esp\n"
+          :
+          : "m" (ar)
+          : "memory", "%eax", "%ebx", "%ecx", "%edx", "%esi", "%edi"
+    );
+#elif defined( _MSC_VER ) && ! defined( _M_AMD64 )
+    __asm {
+	lea	eax, ar
+	mov	[eax], esp         /* save esp, ebp */
+	mov	[eax+4], ebp
+	mov	esp, eax
+	mov	esi, [esp+8]       /* esi = in */
+	mov	edi, [esp+16]      /* edi = out */
+	mov	edx, [esp+40]      /* edx = hold */
+	mov	ebx, [esp+44]      /* ebx = bits */
+	mov	ebp, [esp+32]      /* ebp = lcode */
+
+	cld
+	jmp	L_do_loop
+
+ALIGN 4
+L_while_test:
+	cmp	[esp+24], edi
+	jbe	L_break_loop
+	cmp	[esp+12], esi
+	jbe	L_break_loop
+
+L_do_loop:
+	cmp	bl, 15
+	ja	L_get_length_code    /* if (15 < bits) */
+
+	xor	eax, eax
+	lodsw                         /* al = *(ushort *)in++ */
+	mov	cl, bl            /* cl = bits, needs it for shifting */
+	add	bl, 16             /* bits += 16 */
+	shl	eax, cl
+	or	edx, eax        /* hold |= *((ushort *)in)++ << bits */
+
+L_get_length_code:
+	mov	eax, [esp+56]      /* eax = lmask */
+	and	eax, edx          /* eax &= hold */
+	mov	eax, [ebp+eax*4] /* eax = lcode[hold & lmask] */
+
+L_dolen:
+	mov	cl, ah            /* cl = this.bits */
+	sub	bl, ah            /* bits -= this.bits */
+	shr	edx, cl           /* hold >>= this.bits */
+
+	test	al, al
+	jnz	L_test_for_length_base /* if (op != 0) 45.7% */
+
+	shr	eax, 16            /* output this.val char */
+	stosb
+	jmp	L_while_test
+
+ALIGN 4
+L_test_for_length_base:
+	mov	ecx, eax          /* len = this */
+	shr	ecx, 16            /* len = this.val */
+	mov	[esp+64], ecx      /* save len */
+	mov	cl, al
+
+	test	al, 16
+	jz	L_test_for_second_level_length /* if ((op & 16) == 0) 8% */
+	and	cl, 15             /* op &= 15 */
+	jz	L_decode_distance    /* if (!op) */
+	cmp	bl, cl
+	jae	L_add_bits_to_len    /* if (op <= bits) */
+
+	mov	ch, cl            /* stash op in ch, freeing cl */
+	xor	eax, eax
+	lodsw                         /* al = *(ushort *)in++ */
+	mov	cl, bl            /* cl = bits, needs it for shifting */
+	add	bl, 16             /* bits += 16 */
+	shl	eax, cl
+	or	edx, eax         /* hold |= *((ushort *)in)++ << bits */
+	mov	cl, ch            /* move op back to ecx */
+
+L_add_bits_to_len:
+	sub	bl, cl
+	xor	eax, eax
+	inc	eax
+	shl	eax, cl
+	dec	eax
+	and	eax, edx          /* eax &= hold */
+	shr	edx, cl
+	add	[esp+64], eax      /* len += hold & mask[op] */
+
+L_decode_distance:
+	cmp	bl, 15
+	ja	L_get_distance_code  /* if (15 < bits) */
+
+	xor	eax, eax
+	lodsw                         /* al = *(ushort *)in++ */
+	mov	cl, bl            /* cl = bits, needs it for shifting */
+	add	bl, 16             /* bits += 16 */
+	shl	eax, cl
+	or	edx, eax         /* hold |= *((ushort *)in)++ << bits */
+
+L_get_distance_code:
+	mov	eax, [esp+60]      /* eax = dmask */
+	mov	ecx, [esp+36]      /* ecx = dcode */
+	and	eax, edx          /* eax &= hold */
+	mov	eax, [ecx+eax*4]/* eax = dcode[hold & dmask] */
+
+L_dodist:
+	mov	ebp, eax          /* dist = this */
+	shr	ebp, 16            /* dist = this.val */
+	mov	cl, ah
+	sub	bl, ah            /* bits -= this.bits */
+	shr	edx, cl           /* hold >>= this.bits */
+	mov	cl, al            /* cl = this.op */
+
+	test	al, 16             /* if ((op & 16) == 0) */
+	jz	L_test_for_second_level_dist
+	and	cl, 15             /* op &= 15 */
+	jz	L_check_dist_one
+	cmp	bl, cl
+	jae	L_add_bits_to_dist   /* if (op <= bits) 97.6% */
+
+	mov	ch, cl            /* stash op in ch, freeing cl */
+	xor	eax, eax
+	lodsw                         /* al = *(ushort *)in++ */
+	mov	cl, bl            /* cl = bits, needs it for shifting */
+	add	bl, 16             /* bits += 16 */
+	shl	eax, cl
+	or	edx, eax        /* hold |= *((ushort *)in)++ << bits */
+	mov	cl, ch            /* move op back to ecx */
+
+L_add_bits_to_dist:
+	sub	bl, cl
+	xor	eax, eax
+	inc	eax
+	shl	eax, cl
+	dec	eax                 /* (1 << op) - 1 */
+	and	eax, edx          /* eax &= hold */
+	shr	edx, cl
+	add	ebp, eax          /* dist += hold & ((1 << op) - 1) */
+
+L_check_window:
+	mov	[esp+8], esi       /* save in so from can use it's reg */
+	mov	eax, edi
+	sub	eax, [esp+20]      /* nbytes = out - beg */
+
+	cmp	eax, ebp
+	jb	L_clip_window        /* if (dist > nbytes) 4.2% */
+
+	mov	ecx, [esp+64]      /* ecx = len */
+	mov	esi, edi
+	sub	esi, ebp          /* from = out - dist */
+
+	sar	ecx, 1
+	jnc	L_copy_two
+
+	rep     movsw
+	mov	al, [esi]
+	mov	[edi], al
+	inc	edi
+
+	mov	esi, [esp+8]      /* move in back to %esi, toss from */
+	mov	ebp, [esp+32]     /* ebp = lcode */
+	jmp	L_while_test
+
+L_copy_two:
+	rep     movsw
+	mov	esi, [esp+8]      /* move in back to %esi, toss from */
+	mov	ebp, [esp+32]     /* ebp = lcode */
+	jmp	L_while_test
+
+ALIGN 4
+L_check_dist_one:
+	cmp	ebp, 1            /* if dist 1, is a memset */
+	jne	L_check_window
+	cmp	[esp+20], edi
+	je	L_check_window    /* out == beg, if outside window */
+
+	mov	ecx, [esp+64]     /* ecx = len */
+	mov	al, [edi-1]
+	mov	ah, al
+
+	sar	ecx, 1
+	jnc	L_set_two
+	mov	[edi], al         /* memset out with from[-1] */
+	inc	edi
+
+L_set_two:
+	rep     stosw
+	mov	ebp, [esp+32]     /* ebp = lcode */
+	jmp	L_while_test
+
+ALIGN 4
+L_test_for_second_level_length:
+	test	al, 64
+	jnz	L_test_for_end_of_block /* if ((op & 64) != 0) */
+
+	xor	eax, eax
+	inc	eax
+	shl	eax, cl
+	dec	eax
+	and	eax, edx         /* eax &= hold */
+	add	eax, [esp+64]     /* eax += len */
+	mov	eax, [ebp+eax*4] /* eax = lcode[val+(hold&mask[op])]*/
+	jmp	L_dolen
+
+ALIGN 4
+L_test_for_second_level_dist:
+	test	al, 64
+	jnz	L_invalid_distance_code /* if ((op & 64) != 0) */
+
+	xor	eax, eax
+	inc	eax
+	shl	eax, cl
+	dec	eax
+	and	eax, edx         /* eax &= hold */
+	add	eax, ebp         /* eax += dist */
+	mov	ecx, [esp+36]     /* ecx = dcode */
+	mov	eax, [ecx+eax*4] /* eax = dcode[val+(hold&mask[op])]*/
+	jmp	L_dodist
+
+ALIGN 4
+L_clip_window:
+	mov	ecx, eax
+	mov	eax, [esp+48]     /* eax = wsize */
+	neg	ecx                /* nbytes = -nbytes */
+	mov	esi, [esp+28]     /* from = window */
+
+	cmp	eax, ebp
+	jb	L_invalid_distance_too_far /* if (dist > wsize) */
+
+	add	ecx, ebp         /* nbytes = dist - nbytes */
+	cmp	dword ptr [esp+52], 0
+	jne	L_wrap_around_window /* if (write != 0) */
+
+	sub	eax, ecx
+	add	esi, eax         /* from += wsize - nbytes */
+
+	mov	eax, [esp+64]    /* eax = len */
+	cmp	eax, ecx
+	jbe	L_do_copy          /* if (nbytes >= len) */
+
+	sub	eax, ecx         /* len -= nbytes */
+	rep     movsb
+	mov	esi, edi
+	sub	esi, ebp         /* from = out - dist */
+	jmp	L_do_copy
+
+ALIGN 4
+L_wrap_around_window:
+	mov	eax, [esp+52]    /* eax = write */
+	cmp	ecx, eax
+	jbe	L_contiguous_in_window /* if (write >= nbytes) */
+
+	add	esi, [esp+48]    /* from += wsize */
+	add	esi, eax         /* from += write */
+	sub	esi, ecx         /* from -= nbytes */
+	sub	ecx, eax         /* nbytes -= write */
+
+	mov	eax, [esp+64]    /* eax = len */
+	cmp	eax, ecx
+	jbe	L_do_copy          /* if (nbytes >= len) */
+
+	sub	eax, ecx         /* len -= nbytes */
+	rep     movsb
+	mov	esi, [esp+28]     /* from = window */
+	mov	ecx, [esp+52]     /* nbytes = write */
+	cmp	eax, ecx
+	jbe	L_do_copy          /* if (nbytes >= len) */
+
+	sub	eax, ecx         /* len -= nbytes */
+	rep     movsb
+	mov	esi, edi
+	sub	esi, ebp         /* from = out - dist */
+	jmp	L_do_copy
+
+ALIGN 4
+L_contiguous_in_window:
+	add	esi, eax
+	sub	esi, ecx         /* from += write - nbytes */
+
+	mov	eax, [esp+64]    /* eax = len */
+	cmp	eax, ecx
+	jbe	L_do_copy          /* if (nbytes >= len) */
+
+	sub	eax, ecx         /* len -= nbytes */
+	rep     movsb
+	mov	esi, edi
+	sub	esi, ebp         /* from = out - dist */
+	jmp	L_do_copy
+
+ALIGN 4
+L_do_copy:
+	mov	ecx, eax
+	rep     movsb
+
+	mov	esi, [esp+8]      /* move in back to %esi, toss from */
+	mov	ebp, [esp+32]     /* ebp = lcode */
+	jmp	L_while_test
+
+L_test_for_end_of_block:
+	test	al, 32
+	jz	L_invalid_literal_length_code
+	mov	dword ptr [esp+72], 1
+	jmp	L_break_loop_with_status
+
+L_invalid_literal_length_code:
+	mov	dword ptr [esp+72], 2
+	jmp	L_break_loop_with_status
+
+L_invalid_distance_code:
+	mov	dword ptr [esp+72], 3
+	jmp	L_break_loop_with_status
+
+L_invalid_distance_too_far:
+	mov	esi, [esp+4]
+	mov	dword ptr [esp+72], 4
+	jmp	L_break_loop_with_status
+
+L_break_loop:
+	mov	dword ptr [esp+72], 0
+
+L_break_loop_with_status:
+/* put in, out, bits, and hold back into ar and pop esp */
+	mov	[esp+8], esi     /* save in */
+	mov	[esp+16], edi    /* save out */
+	mov	[esp+44], ebx    /* save bits */
+	mov	[esp+40], edx    /* save hold */
+	mov	ebp, [esp+4]     /* restore esp, ebp */
+	mov	esp, [esp]
+    }
+#else
+#error "x86 architecture not defined"
+#endif
+
+    if (ar.status > 1) {
+        if (ar.status == 2)
+            strm->msg = "invalid literal/length code";
+        else if (ar.status == 3)
+            strm->msg = "invalid distance code";
+        else
+            strm->msg = "invalid distance too far back";
+        state->mode = BAD;
+    }
+    else if ( ar.status == 1 ) {
+        state->mode = TYPE;
+    }
+
+    /* return unused bytes (on entry, bits < 8, so in won't go too far back) */
+    ar.len = ar.bits >> 3;
+    ar.in -= ar.len;
+    ar.bits -= ar.len << 3;
+    ar.hold &= (1U << ar.bits) - 1;
+
+    /* update state and return */
+    strm->next_in = ar.in;
+    strm->next_out = ar.out;
+    strm->avail_in = (unsigned)(ar.in < ar.last ?
+                                PAD_AVAIL_IN + (ar.last - ar.in) :
+                                PAD_AVAIL_IN - (ar.in - ar.last));
+    strm->avail_out = (unsigned)(ar.out < ar.end ?
+                                 PAD_AVAIL_OUT + (ar.end - ar.out) :
+                                 PAD_AVAIL_OUT - (ar.out - ar.end));
+    state->hold = ar.hold;
+    state->bits = ar.bits;
+    return;
+}
+
diff --git a/gs/zlib/contrib/inflate86/inffast.S b/gs/zlib/contrib/inflate86/inffast.S
new file mode 100644
index 000000000..2245a2905
--- /dev/null
+++ b/gs/zlib/contrib/inflate86/inffast.S
@@ -0,0 +1,1368 @@
+/*
+ * inffast.S is a hand tuned assembler version of:
+ *
+ * inffast.c -- fast decoding
+ * Copyright (C) 1995-2003 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ *
+ * Copyright (C) 2003 Chris Anderson <christop@charm.net>
+ * Please use the copyright conditions above.
+ *
+ * This version (Jan-23-2003) of inflate_fast was coded and tested under
+ * GNU/Linux on a pentium 3, using the gcc-3.2 compiler distribution.  On that
+ * machine, I found that gzip style archives decompressed about 20% faster than
+ * the gcc-3.2 -O3 -fomit-frame-pointer compiled version.  Your results will
+ * depend on how large of a buffer is used for z_stream.next_in & next_out
+ * (8K-32K worked best for my 256K cpu cache) and how much overhead there is in
+ * stream processing I/O and crc32/addler32.  In my case, this routine used
+ * 70% of the cpu time and crc32 used 20%.
+ *
+ * I am confident that this version will work in the general case, but I have
+ * not tested a wide variety of datasets or a wide variety of platforms.
+ *
+ * Jan-24-2003 -- Added -DUSE_MMX define for slightly faster inflating.
+ * It should be a runtime flag instead of compile time flag...
+ *
+ * Jan-26-2003 -- Added runtime check for MMX support with cpuid instruction.
+ * With -DUSE_MMX, only MMX code is compiled.  With -DNO_MMX, only non-MMX code
+ * is compiled.  Without either option, runtime detection is enabled.  Runtime
+ * detection should work on all modern cpus and the recomended algorithm (flip
+ * ID bit on eflags and then use the cpuid instruction) is used in many
+ * multimedia applications.  Tested under win2k with gcc-2.95 and gas-2.12
+ * distributed with cygwin3.  Compiling with gcc-2.95 -c inffast.S -o
+ * inffast.obj generates a COFF object which can then be linked with MSVC++
+ * compiled code.  Tested under FreeBSD 4.7 with gcc-2.95.
+ *
+ * Jan-28-2003 -- Tested Athlon XP... MMX mode is slower than no MMX (and
+ * slower than compiler generated code).  Adjusted cpuid check to use the MMX
+ * code only for Pentiums < P4 until I have more data on the P4.  Speed
+ * improvment is only about 15% on the Athlon when compared with code generated
+ * with MSVC++.  Not sure yet, but I think the P4 will also be slower using the
+ * MMX mode because many of it's x86 ALU instructions execute in .5 cycles and
+ * have less latency than MMX ops.  Added code to buffer the last 11 bytes of
+ * the input stream since the MMX code grabs bits in chunks of 32, which
+ * differs from the inffast.c algorithm.  I don't think there would have been
+ * read overruns where a page boundary was crossed (a segfault), but there
+ * could have been overruns when next_in ends on unaligned memory (unintialized
+ * memory read).
+ *
+ * Mar-13-2003 -- P4 MMX is slightly slower than P4 NO_MMX.  I created a C
+ * version of the non-MMX code so that it doesn't depend on zstrm and zstate
+ * structure offsets which are hard coded in this file.  This was last tested
+ * with zlib-1.2.0 which is currently in beta testing, newer versions of this
+ * and inffas86.c can be found at http://www.eetbeetee.com/zlib/ and
+ * http://www.charm.net/~christop/zlib/
+ */
+
+
+/*
+ * if you have underscore linking problems (_inflate_fast undefined), try
+ * using -DGAS_COFF
+ */
+#if ! defined( GAS_COFF ) && ! defined( GAS_ELF )
+
+#if defined( WIN32 ) || defined( __CYGWIN__ )
+#define GAS_COFF /* windows object format */
+#else
+#define GAS_ELF
+#endif
+
+#endif /* ! GAS_COFF && ! GAS_ELF */
+
+
+#if defined( GAS_COFF )
+
+/* coff externals have underscores */
+#define inflate_fast _inflate_fast
+#define inflate_fast_use_mmx _inflate_fast_use_mmx
+
+#endif /* GAS_COFF */
+
+
+.file "inffast.S"
+
+.globl inflate_fast
+
+.text
+.align 4,0
+.L_invalid_literal_length_code_msg:
+.string "invalid literal/length code"
+
+.align 4,0
+.L_invalid_distance_code_msg:
+.string "invalid distance code"
+
+.align 4,0
+.L_invalid_distance_too_far_msg:
+.string "invalid distance too far back"
+
+#if ! defined( NO_MMX )
+.align 4,0
+.L_mask: /* mask[N] = ( 1 << N ) - 1 */
+.long 0
+.long 1
+.long 3
+.long 7
+.long 15
+.long 31
+.long 63
+.long 127
+.long 255
+.long 511
+.long 1023
+.long 2047
+.long 4095
+.long 8191
+.long 16383
+.long 32767
+.long 65535
+.long 131071
+.long 262143
+.long 524287
+.long 1048575
+.long 2097151
+.long 4194303
+.long 8388607
+.long 16777215
+.long 33554431
+.long 67108863
+.long 134217727
+.long 268435455
+.long 536870911
+.long 1073741823
+.long 2147483647
+.long 4294967295
+#endif /* NO_MMX */
+
+.text
+
+/*
+ * struct z_stream offsets, in zlib.h
+ */
+#define next_in_strm   0   /* strm->next_in */
+#define avail_in_strm  4   /* strm->avail_in */
+#define next_out_strm  12  /* strm->next_out */
+#define avail_out_strm 16  /* strm->avail_out */
+#define msg_strm       24  /* strm->msg */
+#define state_strm     28  /* strm->state */
+
+/*
+ * struct inflate_state offsets, in inflate.h
+ */
+#define mode_state     0   /* state->mode */
+#define wsize_state    32  /* state->wsize */
+#define write_state    40  /* state->write */
+#define window_state   44  /* state->window */
+#define hold_state     48  /* state->hold */
+#define bits_state     52  /* state->bits */
+#define lencode_state  68  /* state->lencode */
+#define distcode_state 72  /* state->distcode */
+#define lenbits_state  76  /* state->lenbits */
+#define distbits_state 80  /* state->distbits */
+
+/*
+ * inflate_fast's activation record
+ */
+#define local_var_size 64 /* how much local space for vars */
+#define strm_sp        88 /* first arg: z_stream * (local_var_size + 24) */
+#define start_sp       92 /* second arg: unsigned int (local_var_size + 28) */
+
+/*
+ * offsets for local vars on stack
+ */
+#define out            60  /* unsigned char* */
+#define window         56  /* unsigned char* */
+#define wsize          52  /* unsigned int */
+#define write          48  /* unsigned int */
+#define in             44  /* unsigned char* */
+#define beg            40  /* unsigned char* */
+#define buf            28  /* char[ 12 ] */
+#define len            24  /* unsigned int */
+#define last           20  /* unsigned char* */
+#define end            16  /* unsigned char* */
+#define dcode          12  /* code* */
+#define lcode           8  /* code* */
+#define dmask           4  /* unsigned int */
+#define lmask           0  /* unsigned int */
+
+/*
+ * typedef enum inflate_mode consts, in inflate.h
+ */
+#define INFLATE_MODE_TYPE 11  /* state->mode flags enum-ed in inflate.h */
+#define INFLATE_MODE_BAD  26
+
+
+#if ! defined( USE_MMX ) && ! defined( NO_MMX )
+
+#define RUN_TIME_MMX
+
+#define CHECK_MMX    1
+#define DO_USE_MMX   2
+#define DONT_USE_MMX 3
+
+.globl inflate_fast_use_mmx
+
+.data
+
+.align 4,0
+inflate_fast_use_mmx: /* integer flag for run time control 1=check,2=mmx,3=no */
+.long CHECK_MMX
+
+#if defined( GAS_ELF )
+/* elf info */
+.type   inflate_fast_use_mmx,@object
+.size   inflate_fast_use_mmx,4
+#endif
+
+#endif /* RUN_TIME_MMX */
+
+#if defined( GAS_COFF )
+/* coff info: scl 2 = extern, type 32 = function */
+.def inflate_fast; .scl 2; .type 32; .endef
+#endif
+
+.text
+
+.align 32,0x90
+inflate_fast:
+        pushl   %edi
+        pushl   %esi
+        pushl   %ebp
+        pushl   %ebx
+        pushf   /* save eflags (strm_sp, state_sp assumes this is 32 bits) */
+        subl    $local_var_size, %esp
+        cld
+
+#define strm_r  %esi
+#define state_r %edi
+
+        movl    strm_sp(%esp), strm_r
+        movl    state_strm(strm_r), state_r
+
+        /* in = strm->next_in;
+         * out = strm->next_out;
+         * last = in + strm->avail_in - 11;
+         * beg = out - (start - strm->avail_out);
+         * end = out + (strm->avail_out - 257);
+         */
+        movl    avail_in_strm(strm_r), %edx
+        movl    next_in_strm(strm_r), %eax
+
+        addl    %eax, %edx      /* avail_in += next_in */
+        subl    $11, %edx       /* avail_in -= 11 */
+
+        movl    %eax, in(%esp)
+        movl    %edx, last(%esp)
+
+        movl    start_sp(%esp), %ebp
+        movl    avail_out_strm(strm_r), %ecx
+        movl    next_out_strm(strm_r), %ebx
+
+        subl    %ecx, %ebp      /* start -= avail_out */
+        negl    %ebp            /* start = -start */
+        addl    %ebx, %ebp      /* start += next_out */
+
+        subl    $257, %ecx      /* avail_out -= 257 */
+        addl    %ebx, %ecx      /* avail_out += out */
+
+        movl    %ebx, out(%esp)
+        movl    %ebp, beg(%esp)
+        movl    %ecx, end(%esp)
+
+        /* wsize = state->wsize;
+         * write = state->write;
+         * window = state->window;
+         * hold = state->hold;
+         * bits = state->bits;
+         * lcode = state->lencode;
+         * dcode = state->distcode;
+         * lmask = ( 1 << state->lenbits ) - 1;
+         * dmask = ( 1 << state->distbits ) - 1;
+         */
+
+        movl    lencode_state(state_r), %eax
+        movl    distcode_state(state_r), %ecx
+
+        movl    %eax, lcode(%esp)
+        movl    %ecx, dcode(%esp)
+
+        movl    $1, %eax
+        movl    lenbits_state(state_r), %ecx
+        shll    %cl, %eax
+        decl    %eax
+        movl    %eax, lmask(%esp)
+
+        movl    $1, %eax
+        movl    distbits_state(state_r), %ecx
+        shll    %cl, %eax
+        decl    %eax
+        movl    %eax, dmask(%esp)
+
+        movl    wsize_state(state_r), %eax
+        movl    write_state(state_r), %ecx
+        movl    window_state(state_r), %edx
+
+        movl    %eax, wsize(%esp)
+        movl    %ecx, write(%esp)
+        movl    %edx, window(%esp)
+
+        movl    hold_state(state_r), %ebp
+        movl    bits_state(state_r), %ebx
+
+#undef strm_r
+#undef state_r
+
+#define in_r       %esi
+#define from_r     %esi
+#define out_r      %edi
+
+        movl    in(%esp), in_r
+        movl    last(%esp), %ecx
+        cmpl    in_r, %ecx
+        ja      .L_align_long           /* if in < last */
+
+        addl    $11, %ecx               /* ecx = &in[ avail_in ] */
+        subl    in_r, %ecx              /* ecx = avail_in */
+        movl    $12, %eax
+        subl    %ecx, %eax              /* eax = 12 - avail_in */
+        leal    buf(%esp), %edi
+        rep     movsb                   /* memcpy( buf, in, avail_in ) */
+        movl    %eax, %ecx
+        xorl    %eax, %eax
+        rep     stosb         /* memset( &buf[ avail_in ], 0, 12 - avail_in ) */
+        leal    buf(%esp), in_r         /* in = buf */
+        movl    in_r, last(%esp)        /* last = in, do just one iteration */
+        jmp     .L_is_aligned
+
+        /* align in_r on long boundary */
+.L_align_long:
+        testl   $3, in_r
+        jz      .L_is_aligned
+        xorl    %eax, %eax
+        movb    (in_r), %al
+        incl    in_r
+        movl    %ebx, %ecx
+        addl    $8, %ebx
+        shll    %cl, %eax
+        orl     %eax, %ebp
+        jmp     .L_align_long
+
+.L_is_aligned:
+        movl    out(%esp), out_r
+
+#if defined( NO_MMX )
+        jmp     .L_do_loop
+#endif
+
+#if defined( USE_MMX )
+        jmp     .L_init_mmx
+#endif
+
+/*** Runtime MMX check ***/
+
+#if defined( RUN_TIME_MMX )
+.L_check_mmx:
+        cmpl    $DO_USE_MMX, inflate_fast_use_mmx
+        je      .L_init_mmx
+        ja      .L_do_loop /* > 2 */
+
+        pushl   %eax
+        pushl   %ebx
+        pushl   %ecx
+        pushl   %edx
+        pushf
+        movl    (%esp), %eax      /* copy eflags to eax */
+        xorl    $0x200000, (%esp) /* try toggling ID bit of eflags (bit 21)
+                                   * to see if cpu supports cpuid...
+                                   * ID bit method not supported by NexGen but
+                                   * bios may load a cpuid instruction and
+                                   * cpuid may be disabled on Cyrix 5-6x86 */
+        popf
+        pushf
+        popl    %edx              /* copy new eflags to edx */
+        xorl    %eax, %edx        /* test if ID bit is flipped */
+        jz      .L_dont_use_mmx   /* not flipped if zero */
+        xorl    %eax, %eax
+        cpuid
+        cmpl    $0x756e6547, %ebx /* check for GenuineIntel in ebx,ecx,edx */
+        jne     .L_dont_use_mmx
+        cmpl    $0x6c65746e, %ecx
+        jne     .L_dont_use_mmx
+        cmpl    $0x49656e69, %edx
+        jne     .L_dont_use_mmx
+        movl    $1, %eax
+        cpuid                     /* get cpu features */
+        shrl    $8, %eax
+        andl    $15, %eax
+        cmpl    $6, %eax          /* check for Pentium family, is 0xf for P4 */
+        jne     .L_dont_use_mmx
+        testl   $0x800000, %edx   /* test if MMX feature is set (bit 23) */
+        jnz     .L_use_mmx
+        jmp     .L_dont_use_mmx
+.L_use_mmx:
+        movl    $DO_USE_MMX, inflate_fast_use_mmx
+        jmp     .L_check_mmx_pop
+.L_dont_use_mmx:
+        movl    $DONT_USE_MMX, inflate_fast_use_mmx
+.L_check_mmx_pop:
+        popl    %edx
+        popl    %ecx
+        popl    %ebx
+        popl    %eax
+        jmp     .L_check_mmx
+#endif
+
+
+/*** Non-MMX code ***/
+
+#if defined ( NO_MMX ) || defined( RUN_TIME_MMX )
+
+#define hold_r     %ebp
+#define bits_r     %bl
+#define bitslong_r %ebx
+
+.align 32,0x90
+.L_while_test:
+        /* while (in < last && out < end)
+         */
+        cmpl    out_r, end(%esp)
+        jbe     .L_break_loop           /* if (out >= end) */
+
+        cmpl    in_r, last(%esp)
+        jbe     .L_break_loop
+
+.L_do_loop:
+        /* regs: %esi = in, %ebp = hold, %bl = bits, %edi = out
+         *
+         * do {
+         *   if (bits < 15) {
+         *     hold |= *((unsigned short *)in)++ << bits;
+         *     bits += 16
+         *   }
+         *   this = lcode[hold & lmask]
+         */
+        cmpb    $15, bits_r
+        ja      .L_get_length_code      /* if (15 < bits) */
+
+        xorl    %eax, %eax
+        lodsw                           /* al = *(ushort *)in++ */
+        movb    bits_r, %cl             /* cl = bits, needs it for shifting */
+        addb    $16, bits_r             /* bits += 16 */
+        shll    %cl, %eax
+        orl     %eax, hold_r            /* hold |= *((ushort *)in)++ << bits */
+
+.L_get_length_code:
+        movl    lmask(%esp), %edx       /* edx = lmask */
+        movl    lcode(%esp), %ecx       /* ecx = lcode */
+        andl    hold_r, %edx            /* edx &= hold */
+        movl    (%ecx,%edx,4), %eax     /* eax = lcode[hold & lmask] */
+
+.L_dolen:
+        /* regs: %esi = in, %ebp = hold, %bl = bits, %edi = out
+         *
+         * dolen:
+         *    bits -= this.bits;
+         *    hold >>= this.bits
+         */
+        movb    %ah, %cl                /* cl = this.bits */
+        subb    %ah, bits_r             /* bits -= this.bits */
+        shrl    %cl, hold_r             /* hold >>= this.bits */
+
+        /* check if op is a literal
+         * if (op == 0) {
+         *    PUP(out) = this.val;
+         *  }
+         */
+        testb   %al, %al
+        jnz     .L_test_for_length_base /* if (op != 0) 45.7% */
+
+        shrl    $16, %eax               /* output this.val char */
+        stosb
+        jmp     .L_while_test
+
+.L_test_for_length_base:
+        /* regs: %esi = in, %ebp = hold, %bl = bits, %edi = out, %edx = len
+         *
+         * else if (op & 16) {
+         *   len = this.val
+         *   op &= 15
+         *   if (op) {
+         *     if (op > bits) {
+         *       hold |= *((unsigned short *)in)++ << bits;
+         *       bits += 16
+         *     }
+         *     len += hold & mask[op];
+         *     bits -= op;
+         *     hold >>= op;
+         *   }
+         */
+#define len_r %edx
+        movl    %eax, len_r             /* len = this */
+        shrl    $16, len_r              /* len = this.val */
+        movb    %al, %cl
+
+        testb   $16, %al
+        jz      .L_test_for_second_level_length /* if ((op & 16) == 0) 8% */
+        andb    $15, %cl                /* op &= 15 */
+        jz      .L_save_len             /* if (!op) */
+        cmpb    %cl, bits_r
+        jae     .L_add_bits_to_len      /* if (op <= bits) */
+
+        movb    %cl, %ch                /* stash op in ch, freeing cl */
+        xorl    %eax, %eax
+        lodsw                           /* al = *(ushort *)in++ */
+        movb    bits_r, %cl             /* cl = bits, needs it for shifting */
+        addb    $16, bits_r             /* bits += 16 */
+        shll    %cl, %eax
+        orl     %eax, hold_r            /* hold |= *((ushort *)in)++ << bits */
+        movb    %ch, %cl                /* move op back to ecx */
+
+.L_add_bits_to_len:
+        movl    $1, %eax
+        shll    %cl, %eax
+        decl    %eax
+        subb    %cl, bits_r
+        andl    hold_r, %eax            /* eax &= hold */
+        shrl    %cl, hold_r
+        addl    %eax, len_r             /* len += hold & mask[op] */
+
+.L_save_len:
+        movl    len_r, len(%esp)        /* save len */
+#undef  len_r
+
+.L_decode_distance:
+        /* regs: %esi = in, %ebp = hold, %bl = bits, %edi = out, %edx = dist
+         *
+         *   if (bits < 15) {
+         *     hold |= *((unsigned short *)in)++ << bits;
+         *     bits += 16
+         *   }
+         *   this = dcode[hold & dmask];
+         * dodist:
+         *   bits -= this.bits;
+         *   hold >>= this.bits;
+         *   op = this.op;
+         */
+
+        cmpb    $15, bits_r
+        ja      .L_get_distance_code    /* if (15 < bits) */
+
+        xorl    %eax, %eax
+        lodsw                           /* al = *(ushort *)in++ */
+        movb    bits_r, %cl             /* cl = bits, needs it for shifting */
+        addb    $16, bits_r             /* bits += 16 */
+        shll    %cl, %eax
+        orl     %eax, hold_r            /* hold |= *((ushort *)in)++ << bits */
+
+.L_get_distance_code:
+        movl    dmask(%esp), %edx       /* edx = dmask */
+        movl    dcode(%esp), %ecx       /* ecx = dcode */
+        andl    hold_r, %edx            /* edx &= hold */
+        movl    (%ecx,%edx,4), %eax     /* eax = dcode[hold & dmask] */
+
+#define dist_r %edx
+.L_dodist:
+        movl    %eax, dist_r            /* dist = this */
+        shrl    $16, dist_r             /* dist = this.val */
+        movb    %ah, %cl
+        subb    %ah, bits_r             /* bits -= this.bits */
+        shrl    %cl, hold_r             /* hold >>= this.bits */
+
+        /* if (op & 16) {
+         *   dist = this.val
+         *   op &= 15
+         *   if (op > bits) {
+         *     hold |= *((unsigned short *)in)++ << bits;
+         *     bits += 16
+         *   }
+         *   dist += hold & mask[op];
+         *   bits -= op;
+         *   hold >>= op;
+         */
+        movb    %al, %cl                /* cl = this.op */
+
+        testb   $16, %al                /* if ((op & 16) == 0) */
+        jz      .L_test_for_second_level_dist
+        andb    $15, %cl                /* op &= 15 */
+        jz      .L_check_dist_one
+        cmpb    %cl, bits_r
+        jae     .L_add_bits_to_dist     /* if (op <= bits) 97.6% */
+
+        movb    %cl, %ch                /* stash op in ch, freeing cl */
+        xorl    %eax, %eax
+        lodsw                           /* al = *(ushort *)in++ */
+        movb    bits_r, %cl             /* cl = bits, needs it for shifting */
+        addb    $16, bits_r             /* bits += 16 */
+        shll    %cl, %eax
+        orl     %eax, hold_r            /* hold |= *((ushort *)in)++ << bits */
+        movb    %ch, %cl                /* move op back to ecx */
+
+.L_add_bits_to_dist:
+        movl    $1, %eax
+        shll    %cl, %eax
+        decl    %eax                    /* (1 << op) - 1 */
+        subb    %cl, bits_r
+        andl    hold_r, %eax            /* eax &= hold */
+        shrl    %cl, hold_r
+        addl    %eax, dist_r            /* dist += hold & ((1 << op) - 1) */
+        jmp     .L_check_window
+
+.L_check_window:
+        /* regs: %esi = from, %ebp = hold, %bl = bits, %edi = out, %edx = dist
+         *       %ecx = nbytes
+         *
+         * nbytes = out - beg;
+         * if (dist <= nbytes) {
+         *   from = out - dist;
+         *   do {
+         *     PUP(out) = PUP(from);
+         *   } while (--len > 0) {
+         * }
+         */
+
+        movl    in_r, in(%esp)          /* save in so from can use it's reg */
+        movl    out_r, %eax
+        subl    beg(%esp), %eax         /* nbytes = out - beg */
+
+        cmpl    dist_r, %eax
+        jb      .L_clip_window          /* if (dist > nbytes) 4.2% */
+
+        movl    len(%esp), %ecx
+        movl    out_r, from_r
+        subl    dist_r, from_r          /* from = out - dist */
+
+        subl    $3, %ecx
+        movb    (from_r), %al
+        movb    %al, (out_r)
+        movb    1(from_r), %al
+        movb    2(from_r), %dl
+        addl    $3, from_r
+        movb    %al, 1(out_r)
+        movb    %dl, 2(out_r)
+        addl    $3, out_r
+        rep     movsb
+
+        movl    in(%esp), in_r          /* move in back to %esi, toss from */
+        jmp     .L_while_test
+
+.align 16,0x90
+.L_check_dist_one:
+        cmpl    $1, dist_r
+        jne     .L_check_window
+        cmpl    out_r, beg(%esp)
+        je      .L_check_window
+
+        decl    out_r
+        movl    len(%esp), %ecx
+        movb    (out_r), %al
+        subl    $3, %ecx
+
+        movb    %al, 1(out_r)
+        movb    %al, 2(out_r)
+        movb    %al, 3(out_r)
+        addl    $4, out_r
+        rep     stosb
+
+        jmp     .L_while_test
+
+.align 16,0x90
+.L_test_for_second_level_length:
+        /* else if ((op & 64) == 0) {
+         *   this = lcode[this.val + (hold & mask[op])];
+         * }
+         */
+        testb   $64, %al
+        jnz     .L_test_for_end_of_block  /* if ((op & 64) != 0) */
+
+        movl    $1, %eax
+        shll    %cl, %eax
+        decl    %eax
+        andl    hold_r, %eax            /* eax &= hold */
+        addl    %edx, %eax              /* eax += this.val */
+        movl    lcode(%esp), %edx       /* edx = lcode */
+        movl    (%edx,%eax,4), %eax     /* eax = lcode[val + (hold&mask[op])] */
+        jmp     .L_dolen
+
+.align 16,0x90
+.L_test_for_second_level_dist:
+        /* else if ((op & 64) == 0) {
+         *   this = dcode[this.val + (hold & mask[op])];
+         * }
+         */
+        testb   $64, %al
+        jnz     .L_invalid_distance_code  /* if ((op & 64) != 0) */
+
+        movl    $1, %eax
+        shll    %cl, %eax
+        decl    %eax
+        andl    hold_r, %eax            /* eax &= hold */
+        addl    %edx, %eax              /* eax += this.val */
+        movl    dcode(%esp), %edx       /* edx = dcode */
+        movl    (%edx,%eax,4), %eax     /* eax = dcode[val + (hold&mask[op])] */
+        jmp     .L_dodist
+
+.align 16,0x90
+.L_clip_window:
+        /* regs: %esi = from, %ebp = hold, %bl = bits, %edi = out, %edx = dist
+         *       %ecx = nbytes
+         *
+         * else {
+         *   if (dist > wsize) {
+         *     invalid distance
+         *   }
+         *   from = window;
+         *   nbytes = dist - nbytes;
+         *   if (write == 0) {
+         *     from += wsize - nbytes;
+         */
+#define nbytes_r %ecx
+        movl    %eax, nbytes_r
+        movl    wsize(%esp), %eax       /* prepare for dist compare */
+        negl    nbytes_r                /* nbytes = -nbytes */
+        movl    window(%esp), from_r    /* from = window */
+
+        cmpl    dist_r, %eax
+        jb      .L_invalid_distance_too_far /* if (dist > wsize) */
+
+        addl    dist_r, nbytes_r        /* nbytes = dist - nbytes */
+        cmpl    $0, write(%esp)
+        jne     .L_wrap_around_window   /* if (write != 0) */
+
+        subl    nbytes_r, %eax
+        addl    %eax, from_r            /* from += wsize - nbytes */
+
+        /* regs: %esi = from, %ebp = hold, %bl = bits, %edi = out, %edx = dist
+         *       %ecx = nbytes, %eax = len
+         *
+         *     if (nbytes < len) {
+         *       len -= nbytes;
+         *       do {
+         *         PUP(out) = PUP(from);
+         *       } while (--nbytes);
+         *       from = out - dist;
+         *     }
+         *   }
+         */
+#define len_r %eax
+        movl    len(%esp), len_r
+        cmpl    nbytes_r, len_r
+        jbe     .L_do_copy1             /* if (nbytes >= len) */
+
+        subl    nbytes_r, len_r         /* len -= nbytes */
+        rep     movsb
+        movl    out_r, from_r
+        subl    dist_r, from_r          /* from = out - dist */
+        jmp     .L_do_copy1
+
+        cmpl    nbytes_r, len_r
+        jbe     .L_do_copy1             /* if (nbytes >= len) */
+
+        subl    nbytes_r, len_r         /* len -= nbytes */
+        rep     movsb
+        movl    out_r, from_r
+        subl    dist_r, from_r          /* from = out - dist */
+        jmp     .L_do_copy1
+
+.L_wrap_around_window:
+        /* regs: %esi = from, %ebp = hold, %bl = bits, %edi = out, %edx = dist
+         *       %ecx = nbytes, %eax = write, %eax = len
+         *
+         *   else if (write < nbytes) {
+         *     from += wsize + write - nbytes;
+         *     nbytes -= write;
+         *     if (nbytes < len) {
+         *       len -= nbytes;
+         *       do {
+         *         PUP(out) = PUP(from);
+         *       } while (--nbytes);
+         *       from = window;
+         *       nbytes = write;
+         *       if (nbytes < len) {
+         *         len -= nbytes;
+         *         do {
+         *           PUP(out) = PUP(from);
+         *         } while(--nbytes);
+         *         from = out - dist;
+         *       }
+         *     }
+         *   }
+         */
+#define write_r %eax
+        movl    write(%esp), write_r
+        cmpl    write_r, nbytes_r
+        jbe     .L_contiguous_in_window /* if (write >= nbytes) */
+
+        addl    wsize(%esp), from_r
+        addl    write_r, from_r
+        subl    nbytes_r, from_r        /* from += wsize + write - nbytes */
+        subl    write_r, nbytes_r       /* nbytes -= write */
+#undef write_r
+
+        movl    len(%esp), len_r
+        cmpl    nbytes_r, len_r
+        jbe     .L_do_copy1             /* if (nbytes >= len) */
+
+        subl    nbytes_r, len_r         /* len -= nbytes */
+        rep     movsb
+        movl    window(%esp), from_r    /* from = window */
+        movl    write(%esp), nbytes_r   /* nbytes = write */
+        cmpl    nbytes_r, len_r
+        jbe     .L_do_copy1             /* if (nbytes >= len) */
+
+        subl    nbytes_r, len_r         /* len -= nbytes */
+        rep     movsb
+        movl    out_r, from_r
+        subl    dist_r, from_r          /* from = out - dist */
+        jmp     .L_do_copy1
+
+.L_contiguous_in_window:
+        /* regs: %esi = from, %ebp = hold, %bl = bits, %edi = out, %edx = dist
+         *       %ecx = nbytes, %eax = write, %eax = len
+         *
+         *   else {
+         *     from += write - nbytes;
+         *     if (nbytes < len) {
+         *       len -= nbytes;
+         *       do {
+         *         PUP(out) = PUP(from);
+         *       } while (--nbytes);
+         *       from = out - dist;
+         *     }
+         *   }
+         */
+#define write_r %eax
+        addl    write_r, from_r
+        subl    nbytes_r, from_r        /* from += write - nbytes */
+#undef write_r
+
+        movl    len(%esp), len_r
+        cmpl    nbytes_r, len_r
+        jbe     .L_do_copy1             /* if (nbytes >= len) */
+
+        subl    nbytes_r, len_r         /* len -= nbytes */
+        rep     movsb
+        movl    out_r, from_r
+        subl    dist_r, from_r          /* from = out - dist */
+
+.L_do_copy1:
+        /* regs: %esi = from, %esi = in, %ebp = hold, %bl = bits, %edi = out
+         *       %eax = len
+         *
+         *     while (len > 0) {
+         *       PUP(out) = PUP(from);
+         *       len--;
+         *     }
+         *   }
+         * } while (in < last && out < end);
+         */
+#undef nbytes_r
+#define in_r %esi
+        movl    len_r, %ecx
+        rep     movsb
+
+        movl    in(%esp), in_r          /* move in back to %esi, toss from */
+        jmp     .L_while_test
+
+#undef len_r
+#undef dist_r
+
+#endif /* NO_MMX || RUN_TIME_MMX */
+
+
+/*** MMX code ***/
+
+#if defined( USE_MMX ) || defined( RUN_TIME_MMX )
+
+.align 32,0x90
+.L_init_mmx:
+        emms
+
+#undef  bits_r
+#undef  bitslong_r
+#define bitslong_r %ebp
+#define hold_mm    %mm0
+        movd    %ebp, hold_mm
+        movl    %ebx, bitslong_r
+
+#define used_mm   %mm1
+#define dmask2_mm %mm2
+#define lmask2_mm %mm3
+#define lmask_mm  %mm4
+#define dmask_mm  %mm5
+#define tmp_mm    %mm6
+
+        movd    lmask(%esp), lmask_mm
+        movq    lmask_mm, lmask2_mm
+        movd    dmask(%esp), dmask_mm
+        movq    dmask_mm, dmask2_mm
+        pxor    used_mm, used_mm
+        movl    lcode(%esp), %ebx       /* ebx = lcode */
+        jmp     .L_do_loop_mmx
+
+.align 32,0x90
+.L_while_test_mmx:
+        /* while (in < last && out < end)
+         */
+        cmpl    out_r, end(%esp)
+        jbe     .L_break_loop           /* if (out >= end) */
+
+        cmpl    in_r, last(%esp)
+        jbe     .L_break_loop
+
+.L_do_loop_mmx:
+        psrlq   used_mm, hold_mm        /* hold_mm >>= last bit length */
+
+        cmpl    $32, bitslong_r
+        ja      .L_get_length_code_mmx  /* if (32 < bits) */
+
+        movd    bitslong_r, tmp_mm
+        movd    (in_r), %mm7
+        addl    $4, in_r
+        psllq   tmp_mm, %mm7
+        addl    $32, bitslong_r
+        por     %mm7, hold_mm           /* hold_mm |= *((uint *)in)++ << bits */
+
+.L_get_length_code_mmx:
+        pand    hold_mm, lmask_mm
+        movd    lmask_mm, %eax
+        movq    lmask2_mm, lmask_mm
+        movl    (%ebx,%eax,4), %eax     /* eax = lcode[hold & lmask] */
+
+.L_dolen_mmx:
+        movzbl  %ah, %ecx               /* ecx = this.bits */
+        movd    %ecx, used_mm
+        subl    %ecx, bitslong_r        /* bits -= this.bits */
+
+        testb   %al, %al
+        jnz     .L_test_for_length_base_mmx /* if (op != 0) 45.7% */
+
+        shrl    $16, %eax               /* output this.val char */
+        stosb
+        jmp     .L_while_test_mmx
+
+.L_test_for_length_base_mmx:
+#define len_r  %edx
+        movl    %eax, len_r             /* len = this */
+        shrl    $16, len_r              /* len = this.val */
+
+        testb   $16, %al
+        jz      .L_test_for_second_level_length_mmx /* if ((op & 16) == 0) 8% */
+        andl    $15, %eax               /* op &= 15 */
+        jz      .L_decode_distance_mmx  /* if (!op) */
+
+        psrlq   used_mm, hold_mm        /* hold_mm >>= last bit length */
+        movd    %eax, used_mm
+        movd    hold_mm, %ecx
+        subl    %eax, bitslong_r
+        andl    .L_mask(,%eax,4), %ecx
+        addl    %ecx, len_r             /* len += hold & mask[op] */
+
+.L_decode_distance_mmx:
+        psrlq   used_mm, hold_mm        /* hold_mm >>= last bit length */
+
+        cmpl    $32, bitslong_r
+        ja      .L_get_dist_code_mmx    /* if (32 < bits) */
+
+        movd    bitslong_r, tmp_mm
+        movd    (in_r), %mm7
+        addl    $4, in_r
+        psllq   tmp_mm, %mm7
+        addl    $32, bitslong_r
+        por     %mm7, hold_mm           /* hold_mm |= *((uint *)in)++ << bits */
+
+.L_get_dist_code_mmx:
+        movl    dcode(%esp), %ebx       /* ebx = dcode */
+        pand    hold_mm, dmask_mm
+        movd    dmask_mm, %eax
+        movq    dmask2_mm, dmask_mm
+        movl    (%ebx,%eax,4), %eax     /* eax = dcode[hold & lmask] */
+
+.L_dodist_mmx:
+#define dist_r %ebx
+        movzbl  %ah, %ecx               /* ecx = this.bits */
+        movl    %eax, dist_r
+        shrl    $16, dist_r             /* dist  = this.val */
+        subl    %ecx, bitslong_r        /* bits -= this.bits */
+        movd    %ecx, used_mm
+
+        testb   $16, %al                /* if ((op & 16) == 0) */
+        jz      .L_test_for_second_level_dist_mmx
+        andl    $15, %eax               /* op &= 15 */
+        jz      .L_check_dist_one_mmx
+
+.L_add_bits_to_dist_mmx:
+        psrlq   used_mm, hold_mm        /* hold_mm >>= last bit length */
+        movd    %eax, used_mm           /* save bit length of current op */
+        movd    hold_mm, %ecx           /* get the next bits on input stream */
+        subl    %eax, bitslong_r        /* bits -= op bits */
+        andl    .L_mask(,%eax,4), %ecx  /* ecx   = hold & mask[op] */
+        addl    %ecx, dist_r            /* dist += hold & mask[op] */
+
+.L_check_window_mmx:
+        movl    in_r, in(%esp)          /* save in so from can use it's reg */
+        movl    out_r, %eax
+        subl    beg(%esp), %eax         /* nbytes = out - beg */
+
+        cmpl    dist_r, %eax
+        jb      .L_clip_window_mmx      /* if (dist > nbytes) 4.2% */
+
+        movl    len_r, %ecx
+        movl    out_r, from_r
+        subl    dist_r, from_r          /* from = out - dist */
+
+        subl    $3, %ecx
+        movb    (from_r), %al
+        movb    %al, (out_r)
+        movb    1(from_r), %al
+        movb    2(from_r), %dl
+        addl    $3, from_r
+        movb    %al, 1(out_r)
+        movb    %dl, 2(out_r)
+        addl    $3, out_r
+        rep     movsb
+
+        movl    in(%esp), in_r          /* move in back to %esi, toss from */
+        movl    lcode(%esp), %ebx       /* move lcode back to %ebx, toss dist */
+        jmp     .L_while_test_mmx
+
+.align 16,0x90
+.L_check_dist_one_mmx:
+        cmpl    $1, dist_r
+        jne     .L_check_window_mmx
+        cmpl    out_r, beg(%esp)
+        je      .L_check_window_mmx
+
+        decl    out_r
+        movl    len_r, %ecx
+        movb    (out_r), %al
+        subl    $3, %ecx
+
+        movb    %al, 1(out_r)
+        movb    %al, 2(out_r)
+        movb    %al, 3(out_r)
+        addl    $4, out_r
+        rep     stosb
+
+        movl    lcode(%esp), %ebx       /* move lcode back to %ebx, toss dist */
+        jmp     .L_while_test_mmx
+
+.align 16,0x90
+.L_test_for_second_level_length_mmx:
+        testb   $64, %al
+        jnz     .L_test_for_end_of_block  /* if ((op & 64) != 0) */
+
+        andl    $15, %eax
+        psrlq   used_mm, hold_mm        /* hold_mm >>= last bit length */
+        movd    hold_mm, %ecx
+        andl    .L_mask(,%eax,4), %ecx
+        addl    len_r, %ecx
+        movl    (%ebx,%ecx,4), %eax     /* eax = lcode[hold & lmask] */
+        jmp     .L_dolen_mmx
+
+.align 16,0x90
+.L_test_for_second_level_dist_mmx:
+        testb   $64, %al
+        jnz     .L_invalid_distance_code  /* if ((op & 64) != 0) */
+
+        andl    $15, %eax
+        psrlq   used_mm, hold_mm        /* hold_mm >>= last bit length */
+        movd    hold_mm, %ecx
+        andl    .L_mask(,%eax,4), %ecx
+        movl    dcode(%esp), %eax       /* ecx = dcode */
+        addl    dist_r, %ecx
+        movl    (%eax,%ecx,4), %eax     /* eax = lcode[hold & lmask] */
+        jmp     .L_dodist_mmx
+
+.align 16,0x90
+.L_clip_window_mmx:
+#define nbytes_r %ecx
+        movl    %eax, nbytes_r
+        movl    wsize(%esp), %eax       /* prepare for dist compare */
+        negl    nbytes_r                /* nbytes = -nbytes */
+        movl    window(%esp), from_r    /* from = window */
+
+        cmpl    dist_r, %eax
+        jb      .L_invalid_distance_too_far /* if (dist > wsize) */
+
+        addl    dist_r, nbytes_r        /* nbytes = dist - nbytes */
+        cmpl    $0, write(%esp)
+        jne     .L_wrap_around_window_mmx /* if (write != 0) */
+
+        subl    nbytes_r, %eax
+        addl    %eax, from_r            /* from += wsize - nbytes */
+
+        cmpl    nbytes_r, len_r
+        jbe     .L_do_copy1_mmx         /* if (nbytes >= len) */
+
+        subl    nbytes_r, len_r         /* len -= nbytes */
+        rep     movsb
+        movl    out_r, from_r
+        subl    dist_r, from_r          /* from = out - dist */
+        jmp     .L_do_copy1_mmx
+
+        cmpl    nbytes_r, len_r
+        jbe     .L_do_copy1_mmx         /* if (nbytes >= len) */
+
+        subl    nbytes_r, len_r         /* len -= nbytes */
+        rep     movsb
+        movl    out_r, from_r
+        subl    dist_r, from_r          /* from = out - dist */
+        jmp     .L_do_copy1_mmx
+
+.L_wrap_around_window_mmx:
+#define write_r %eax
+        movl    write(%esp), write_r
+        cmpl    write_r, nbytes_r
+        jbe     .L_contiguous_in_window_mmx /* if (write >= nbytes) */
+
+        addl    wsize(%esp), from_r
+        addl    write_r, from_r
+        subl    nbytes_r, from_r        /* from += wsize + write - nbytes */
+        subl    write_r, nbytes_r       /* nbytes -= write */
+#undef write_r
+
+        cmpl    nbytes_r, len_r
+        jbe     .L_do_copy1_mmx         /* if (nbytes >= len) */
+
+        subl    nbytes_r, len_r         /* len -= nbytes */
+        rep     movsb
+        movl    window(%esp), from_r    /* from = window */
+        movl    write(%esp), nbytes_r   /* nbytes = write */
+        cmpl    nbytes_r, len_r
+        jbe     .L_do_copy1_mmx         /* if (nbytes >= len) */
+
+        subl    nbytes_r, len_r         /* len -= nbytes */
+        rep     movsb
+        movl    out_r, from_r
+        subl    dist_r, from_r          /* from = out - dist */
+        jmp     .L_do_copy1_mmx
+
+.L_contiguous_in_window_mmx:
+#define write_r %eax
+        addl    write_r, from_r
+        subl    nbytes_r, from_r        /* from += write - nbytes */
+#undef write_r
+
+        cmpl    nbytes_r, len_r
+        jbe     .L_do_copy1_mmx         /* if (nbytes >= len) */
+
+        subl    nbytes_r, len_r         /* len -= nbytes */
+        rep     movsb
+        movl    out_r, from_r
+        subl    dist_r, from_r          /* from = out - dist */
+
+.L_do_copy1_mmx:
+#undef nbytes_r
+#define in_r %esi
+        movl    len_r, %ecx
+        rep     movsb
+
+        movl    in(%esp), in_r          /* move in back to %esi, toss from */
+        movl    lcode(%esp), %ebx       /* move lcode back to %ebx, toss dist */
+        jmp     .L_while_test_mmx
+
+#undef hold_r
+#undef bitslong_r
+
+#endif /* USE_MMX || RUN_TIME_MMX */
+
+
+/*** USE_MMX, NO_MMX, and RUNTIME_MMX from here on ***/
+
+.L_invalid_distance_code:
+        /* else {
+         *   strm->msg = "invalid distance code";
+         *   state->mode = BAD;
+         * }
+         */
+        movl    $.L_invalid_distance_code_msg, %ecx
+        movl    $INFLATE_MODE_BAD, %edx
+        jmp     .L_update_stream_state
+
+.L_test_for_end_of_block:
+        /* else if (op & 32) {
+         *   state->mode = TYPE;
+         *   break;
+         * }
+         */
+        testb   $32, %al
+        jz      .L_invalid_literal_length_code  /* if ((op & 32) == 0) */
+
+        movl    $0, %ecx
+        movl    $INFLATE_MODE_TYPE, %edx
+        jmp     .L_update_stream_state
+
+.L_invalid_literal_length_code:
+        /* else {
+         *   strm->msg = "invalid literal/length code";
+         *   state->mode = BAD;
+         * }
+         */
+        movl    $.L_invalid_literal_length_code_msg, %ecx
+        movl    $INFLATE_MODE_BAD, %edx
+        jmp     .L_update_stream_state
+
+.L_invalid_distance_too_far:
+        /* strm->msg = "invalid distance too far back";
+         * state->mode = BAD;
+         */
+        movl    in(%esp), in_r          /* from_r has in's reg, put in back */
+        movl    $.L_invalid_distance_too_far_msg, %ecx
+        movl    $INFLATE_MODE_BAD, %edx
+        jmp     .L_update_stream_state
+
+.L_update_stream_state:
+        /* set strm->msg = %ecx, strm->state->mode = %edx */
+        movl    strm_sp(%esp), %eax
+        testl   %ecx, %ecx              /* if (msg != NULL) */
+        jz      .L_skip_msg
+        movl    %ecx, msg_strm(%eax)    /* strm->msg = msg */
+.L_skip_msg:
+        movl    state_strm(%eax), %eax  /* state = strm->state */
+        movl    %edx, mode_state(%eax)  /* state->mode = edx (BAD | TYPE) */
+        jmp     .L_break_loop
+
+.align 32,0x90
+.L_break_loop:
+
+/*
+ * Regs:
+ *
+ * bits = %ebp when mmx, and in %ebx when non-mmx
+ * hold = %hold_mm when mmx, and in %ebp when non-mmx
+ * in   = %esi
+ * out  = %edi
+ */
+
+#if defined( USE_MMX ) || defined( RUN_TIME_MMX )
+
+#if defined( RUN_TIME_MMX )
+
+        cmpl    $DO_USE_MMX, inflate_fast_use_mmx
+        jne     .L_update_next_in
+
+#endif /* RUN_TIME_MMX */
+
+        movl    %ebp, %ebx
+
+.L_update_next_in:
+
+#endif
+
+#define strm_r  %eax
+#define state_r %edx
+
+        /* len = bits >> 3;
+         * in -= len;
+         * bits -= len << 3;
+         * hold &= (1U << bits) - 1;
+         * state->hold = hold;
+         * state->bits = bits;
+         * strm->next_in = in;
+         * strm->next_out = out;
+         */
+        movl    strm_sp(%esp), strm_r
+        movl    %ebx, %ecx
+        movl    state_strm(strm_r), state_r
+        shrl    $3, %ecx
+        subl    %ecx, in_r
+        shll    $3, %ecx
+        subl    %ecx, %ebx
+        movl    out_r, next_out_strm(strm_r)
+        movl    %ebx, bits_state(state_r)
+        movl    %ebx, %ecx
+
+        leal    buf(%esp), %ebx
+        cmpl    %ebx, last(%esp)
+        jne     .L_buf_not_used         /* if buf != last */
+
+        subl    %ebx, in_r              /* in -= buf */
+        movl    next_in_strm(strm_r), %ebx
+        movl    %ebx, last(%esp)        /* last = strm->next_in */
+        addl    %ebx, in_r              /* in += strm->next_in */
+        movl    avail_in_strm(strm_r), %ebx
+        subl    $11, %ebx
+        addl    %ebx, last(%esp)    /* last = &strm->next_in[ avail_in - 11 ] */
+
+.L_buf_not_used:
+        movl    in_r, next_in_strm(strm_r)
+
+        movl    $1, %ebx
+        shll    %cl, %ebx
+        decl    %ebx
+
+#if defined( USE_MMX ) || defined( RUN_TIME_MMX )
+
+#if defined( RUN_TIME_MMX )
+
+        cmpl    $DO_USE_MMX, inflate_fast_use_mmx
+        jne     .L_update_hold
+
+#endif /* RUN_TIME_MMX */
+
+        psrlq   used_mm, hold_mm        /* hold_mm >>= last bit length */
+        movd    hold_mm, %ebp
+
+        emms
+
+.L_update_hold:
+
+#endif /* USE_MMX || RUN_TIME_MMX */
+
+        andl    %ebx, %ebp
+        movl    %ebp, hold_state(state_r)
+
+#define last_r %ebx
+
+        /* strm->avail_in = in < last ? 11 + (last - in) : 11 - (in - last) */
+        movl    last(%esp), last_r
+        cmpl    in_r, last_r
+        jbe     .L_last_is_smaller     /* if (in >= last) */
+
+        subl    in_r, last_r           /* last -= in */
+        addl    $11, last_r            /* last += 11 */
+        movl    last_r, avail_in_strm(strm_r)
+        jmp     .L_fixup_out
+.L_last_is_smaller:
+        subl    last_r, in_r           /* in -= last */
+        negl    in_r                   /* in = -in */
+        addl    $11, in_r              /* in += 11 */
+        movl    in_r, avail_in_strm(strm_r)
+
+#undef last_r
+#define end_r %ebx
+
+.L_fixup_out:
+        /* strm->avail_out = out < end ? 257 + (end - out) : 257 - (out - end)*/
+        movl    end(%esp), end_r
+        cmpl    out_r, end_r
+        jbe     .L_end_is_smaller      /* if (out >= end) */
+
+        subl    out_r, end_r           /* end -= out */
+        addl    $257, end_r            /* end += 257 */
+        movl    end_r, avail_out_strm(strm_r)
+        jmp     .L_done
+.L_end_is_smaller:
+        subl    end_r, out_r           /* out -= end */
+        negl    out_r                  /* out = -out */
+        addl    $257, out_r            /* out += 257 */
+        movl    out_r, avail_out_strm(strm_r)
+
+#undef end_r
+#undef strm_r
+#undef state_r
+
+.L_done:
+        addl    $local_var_size, %esp
+        popf
+        popl    %ebx
+        popl    %ebp
+        popl    %esi
+        popl    %edi
+        ret
+
+#if defined( GAS_ELF )
+/* elf info */
+.type inflate_fast,@function
+.size inflate_fast,.-inflate_fast
+#endif
diff --git a/gs/zlib/contrib/iostream/test.cpp b/gs/zlib/contrib/iostream/test.cpp
new file mode 100644
index 000000000..7d265b3b5
--- /dev/null
+++ b/gs/zlib/contrib/iostream/test.cpp
@@ -0,0 +1,24 @@
+
+#include "zfstream.h"
+
+int main() {
+
+  // Construct a stream object with this filebuffer.  Anything sent
+  // to this stream will go to standard out.
+  gzofstream os( 1, ios::out );
+
+  // This text is getting compressed and sent to stdout.
+  // To prove this, run 'test | zcat'.
+  os << "Hello, Mommy" << endl;
+
+  os << setcompressionlevel( Z_NO_COMPRESSION );
+  os << "hello, hello, hi, ho!" << endl;
+
+  setcompressionlevel( os, Z_DEFAULT_COMPRESSION )
+    << "I'm compressing again" << endl;
+
+  os.close();
+
+  return 0;
+
+}
diff --git a/gs/zlib/contrib/iostream/zfstream.cpp b/gs/zlib/contrib/iostream/zfstream.cpp
new file mode 100644
index 000000000..d0cd85faa
--- /dev/null
+++ b/gs/zlib/contrib/iostream/zfstream.cpp
@@ -0,0 +1,329 @@
+
+#include "zfstream.h"
+
+gzfilebuf::gzfilebuf() :
+  file(NULL),
+  mode(0),
+  own_file_descriptor(0)
+{ }
+
+gzfilebuf::~gzfilebuf() {
+
+  sync();
+  if ( own_file_descriptor )
+    close();
+
+}
+
+gzfilebuf *gzfilebuf::open( const char *name,
+                            int io_mode ) {
+
+  if ( is_open() )
+    return NULL;
+
+  char char_mode[10];
+  char *p = char_mode;
+
+  if ( io_mode & ios::in ) {
+    mode = ios::in;
+    *p++ = 'r';
+  } else if ( io_mode & ios::app ) {
+    mode = ios::app;
+    *p++ = 'a';
+  } else {
+    mode = ios::out;
+    *p++ = 'w';
+  }
+
+  if ( io_mode & ios::binary ) {
+    mode |= ios::binary;
+    *p++ = 'b';
+  }
+
+  // Hard code the compression level
+  if ( io_mode & (ios::out|ios::app )) {
+    *p++ = '9';
+  }
+
+  // Put the end-of-string indicator
+  *p = '\0';
+
+  if ( (file = gzopen(name, char_mode)) == NULL )
+    return NULL;
+
+  own_file_descriptor = 1;
+
+  return this;
+
+}
+
+gzfilebuf *gzfilebuf::attach( int file_descriptor,
+                              int io_mode ) {
+
+  if ( is_open() )
+    return NULL;
+
+  char char_mode[10];
+  char *p = char_mode;
+
+  if ( io_mode & ios::in ) {
+    mode = ios::in;
+    *p++ = 'r';
+  } else if ( io_mode & ios::app ) {
+    mode = ios::app;
+    *p++ = 'a';
+  } else {
+    mode = ios::out;
+    *p++ = 'w';
+  }
+
+  if ( io_mode & ios::binary ) {
+    mode |= ios::binary;
+    *p++ = 'b';
+  }
+
+  // Hard code the compression level
+  if ( io_mode & (ios::out|ios::app )) {
+    *p++ = '9';
+  }
+
+  // Put the end-of-string indicator
+  *p = '\0';
+
+  if ( (file = gzdopen(file_descriptor, char_mode)) == NULL )
+    return NULL;
+
+  own_file_descriptor = 0;
+
+  return this;
+
+}
+
+gzfilebuf *gzfilebuf::close() {
+
+  if ( is_open() ) {
+
+    sync();
+    gzclose( file );
+    file = NULL;
+
+  }
+
+  return this;
+
+}
+
+int gzfilebuf::setcompressionlevel( int comp_level ) {
+
+  return gzsetparams(file, comp_level, -2);
+
+}
+
+int gzfilebuf::setcompressionstrategy( int comp_strategy ) {
+
+  return gzsetparams(file, -2, comp_strategy);
+
+}
+
+
+streampos gzfilebuf::seekoff( streamoff off, ios::seek_dir dir, int which ) {
+
+  return streampos(EOF);
+
+}
+
+int gzfilebuf::underflow() {
+
+  // If the file hasn't been opened for reading, error.
+  if ( !is_open() || !(mode & ios::in) )
+    return EOF;
+
+  // if a buffer doesn't exists, allocate one.
+  if ( !base() ) {
+
+    if ( (allocate()) == EOF )
+      return EOF;
+    setp(0,0);
+
+  } else {
+
+    if ( in_avail() )
+      return (unsigned char) *gptr();
+
+    if ( out_waiting() ) {
+      if ( flushbuf() == EOF )
+        return EOF;
+    }
+
+  }
+
+  // Attempt to fill the buffer.
+
+  int result = fillbuf();
+  if ( result == EOF ) {
+    // disable get area
+    setg(0,0,0);
+    return EOF;
+  }
+
+  return (unsigned char) *gptr();
+
+}
+
+int gzfilebuf::overflow( int c ) {
+
+  if ( !is_open() || !(mode & ios::out) )
+    return EOF;
+
+  if ( !base() ) {
+    if ( allocate() == EOF )
+      return EOF;
+    setg(0,0,0);
+  } else {
+    if (in_avail()) {
+        return EOF;
+    }
+    if (out_waiting()) {
+      if (flushbuf() == EOF)
+        return EOF;
+    }
+  }
+
+  int bl = blen();
+  setp( base(), base() + bl);
+
+  if ( c != EOF ) {
+
+    *pptr() = c;
+    pbump(1);
+
+  }
+
+  return 0;
+
+}
+
+int gzfilebuf::sync() {
+
+  if ( !is_open() )
+    return EOF;
+
+  if ( out_waiting() )
+    return flushbuf();
+
+  return 0;
+
+}
+
+int gzfilebuf::flushbuf() {
+
+  int n;
+  char *q;
+
+  q = pbase();
+  n = pptr() - q;
+
+  if ( gzwrite( file, q, n) < n )
+    return EOF;
+
+  setp(0,0);
+
+  return 0;
+
+}
+
+int gzfilebuf::fillbuf() {
+
+  int required;
+  char *p;
+
+  p = base();
+
+  required = blen();
+
+  int t = gzread( file, p, required );
+
+  if ( t <= 0) return EOF;
+
+  setg( base(), base(), base()+t);
+
+  return t;
+
+}
+
+gzfilestream_common::gzfilestream_common() :
+  ios( gzfilestream_common::rdbuf() )
+{ }
+
+gzfilestream_common::~gzfilestream_common()
+{ }
+
+void gzfilestream_common::attach( int fd, int io_mode ) {
+
+  if ( !buffer.attach( fd, io_mode) )
+    clear( ios::failbit | ios::badbit );
+  else
+    clear();
+
+}
+
+void gzfilestream_common::open( const char *name, int io_mode ) {
+
+  if ( !buffer.open( name, io_mode ) )
+    clear( ios::failbit | ios::badbit );
+  else
+    clear();
+
+}
+
+void gzfilestream_common::close() {
+
+  if ( !buffer.close() )
+    clear( ios::failbit | ios::badbit );
+
+}
+
+gzfilebuf *gzfilestream_common::rdbuf()
+{
+  return &buffer;
+}
+
+gzifstream::gzifstream() :
+  ios( gzfilestream_common::rdbuf() )
+{
+  clear( ios::badbit );
+}
+
+gzifstream::gzifstream( const char *name, int io_mode ) :
+  ios( gzfilestream_common::rdbuf() )
+{
+  gzfilestream_common::open( name, io_mode );
+}
+
+gzifstream::gzifstream( int fd, int io_mode ) :
+  ios( gzfilestream_common::rdbuf() )
+{
+  gzfilestream_common::attach( fd, io_mode );
+}
+
+gzifstream::~gzifstream() { }
+
+gzofstream::gzofstream() :
+  ios( gzfilestream_common::rdbuf() )
+{
+  clear( ios::badbit );
+}
+
+gzofstream::gzofstream( const char *name, int io_mode ) :
+  ios( gzfilestream_common::rdbuf() )
+{
+  gzfilestream_common::open( name, io_mode );
+}
+
+gzofstream::gzofstream( int fd, int io_mode ) :
+  ios( gzfilestream_common::rdbuf() )
+{
+  gzfilestream_common::attach( fd, io_mode );
+}
+
+gzofstream::~gzofstream() { }
diff --git a/gs/zlib/contrib/iostream/zfstream.h b/gs/zlib/contrib/iostream/zfstream.h
new file mode 100644
index 000000000..ed79098a3
--- /dev/null
+++ b/gs/zlib/contrib/iostream/zfstream.h
@@ -0,0 +1,128 @@
+
+#ifndef zfstream_h
+#define zfstream_h
+
+#include <fstream.h>
+#include "zlib.h"
+
+class gzfilebuf : public streambuf {
+
+public:
+
+  gzfilebuf( );
+  virtual ~gzfilebuf();
+
+  gzfilebuf *open( const char *name, int io_mode );
+  gzfilebuf *attach( int file_descriptor, int io_mode );
+  gzfilebuf *close();
+
+  int setcompressionlevel( int comp_level );
+  int setcompressionstrategy( int comp_strategy );
+
+  inline int is_open() const { return (file !=NULL); }
+
+  virtual streampos seekoff( streamoff, ios::seek_dir, int );
+
+  virtual int sync();
+
+protected:
+
+  virtual int underflow();
+  virtual int overflow( int = EOF );
+
+private:
+
+  gzFile file;
+  short mode;
+  short own_file_descriptor;
+
+  int flushbuf();
+  int fillbuf();
+
+};
+
+class gzfilestream_common : virtual public ios {
+
+  friend class gzifstream;
+  friend class gzofstream;
+  friend gzofstream &setcompressionlevel( gzofstream &, int );
+  friend gzofstream &setcompressionstrategy( gzofstream &, int );
+
+public:
+  virtual ~gzfilestream_common();
+
+  void attach( int fd, int io_mode );
+  void open( const char *name, int io_mode );
+  void close();
+
+protected:
+  gzfilestream_common();
+
+private:
+  gzfilebuf *rdbuf();
+
+  gzfilebuf buffer;
+
+};
+
+class gzifstream : public gzfilestream_common, public istream {
+
+public:
+
+  gzifstream();
+  gzifstream( const char *name, int io_mode = ios::in );
+  gzifstream( int fd, int io_mode = ios::in );
+
+  virtual ~gzifstream();
+
+};
+
+class gzofstream : public gzfilestream_common, public ostream {
+
+public:
+
+  gzofstream();
+  gzofstream( const char *name, int io_mode = ios::out );
+  gzofstream( int fd, int io_mode = ios::out );
+
+  virtual ~gzofstream();
+
+};
+
+template<class T> class gzomanip {
+  friend gzofstream &operator<<(gzofstream &, const gzomanip<T> &);
+public:
+  gzomanip(gzofstream &(*f)(gzofstream &, T), T v) : func(f), val(v) { }
+private:
+  gzofstream &(*func)(gzofstream &, T);
+  T val;
+};
+
+template<class T> gzofstream &operator<<(gzofstream &s, const gzomanip<T> &m)
+{
+  return (*m.func)(s, m.val);
+}
+
+inline gzofstream &setcompressionlevel( gzofstream &s, int l )
+{
+  (s.rdbuf())->setcompressionlevel(l);
+  return s;
+}
+
+inline gzofstream &setcompressionstrategy( gzofstream &s, int l )
+{
+  (s.rdbuf())->setcompressionstrategy(l);
+  return s;
+}
+
+inline gzomanip<int> setcompressionlevel(int l)
+{
+  return gzomanip<int>(&setcompressionlevel,l);
+}
+
+inline gzomanip<int> setcompressionstrategy(int l)
+{
+  return gzomanip<int>(&setcompressionstrategy,l);
+}
+
+#endif
diff --git a/gs/zlib/contrib/iostream2/zstream.h b/gs/zlib/contrib/iostream2/zstream.h
new file mode 100644
index 000000000..43d2332b7
--- /dev/null
+++ b/gs/zlib/contrib/iostream2/zstream.h
@@ -0,0 +1,307 @@
+/*
+ *
+ * Copyright (c) 1997
+ * Christian Michelsen Research AS
+ * Advanced Computing
+ * Fantoftvegen 38, 5036 BERGEN, Norway
+ * http://www.cmr.no
+ *
+ * Permission to use, copy, modify, distribute and sell this software
+ * and its documentation for any purpose is hereby granted without fee,
+ * provided that the above copyright notice appear in all copies and
+ * that both that copyright notice and this permission notice appear
+ * in supporting documentation.  Christian Michelsen Research AS makes no
+ * representations about the suitability of this software for any
+ * purpose.  It is provided "as is" without express or implied warranty.
+ *
+ */
+
+#ifndef ZSTREAM__H
+#define ZSTREAM__H
+
+/*
+ * zstream.h - C++ interface to the 'zlib' general purpose compression library
+ * $Id: zstream.h 1.1 1997-06-25 12:00:56+02 tyge Exp tyge $
+ */
+
+#include <strstream.h>
+#include <string.h>
+#include <stdio.h>
+#include "zlib.h"
+
+#if defined(_WIN32)
+#   include <fcntl.h>
+#   include <io.h>
+#   define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
+#else
+#   define SET_BINARY_MODE(file)
+#endif
+
+class zstringlen {
+public:
+    zstringlen(class izstream&);
+    zstringlen(class ozstream&, const char*);
+    size_t value() const { return val.word; }
+private:
+    struct Val { unsigned char byte; size_t word; } val;
+};
+
+//  ----------------------------- izstream -----------------------------
+
+class izstream
+{
+    public:
+        izstream() : m_fp(0) {}
+        izstream(FILE* fp) : m_fp(0) { open(fp); }
+        izstream(const char* name) : m_fp(0) { open(name); }
+        ~izstream() { close(); }
+
+        /* Opens a gzip (.gz) file for reading.
+         * open() can be used to read a file which is not in gzip format;
+         * in this case read() will directly read from the file without
+         * decompression. errno can be checked to distinguish two error
+         * cases (if errno is zero, the zlib error is Z_MEM_ERROR).
+         */
+        void open(const char* name) {
+            if (m_fp) close();
+            m_fp = ::gzopen(name, "rb");
+        }
+
+        void open(FILE* fp) {
+            SET_BINARY_MODE(fp);
+            if (m_fp) close();
+            m_fp = ::gzdopen(fileno(fp), "rb");
+        }
+
+        /* Flushes all pending input if necessary, closes the compressed file
+         * and deallocates all the (de)compression state. The return value is
+         * the zlib error number (see function error() below).
+         */
+        int close() {
+            int r = ::gzclose(m_fp);
+            m_fp = 0; return r;
+        }
+
+        /* Binary read the given number of bytes from the compressed file.
+         */
+        int read(void* buf, size_t len) {
+            return ::gzread(m_fp, buf, len);
+        }
+
+        /* Returns the error message for the last error which occurred on the
+         * given compressed file. errnum is set to zlib error number. If an
+         * error occurred in the file system and not in the compression library,
+         * errnum is set to Z_ERRNO and the application may consult errno
+         * to get the exact error code.
+         */
+        const char* error(int* errnum) {
+            return ::gzerror(m_fp, errnum);
+        }
+
+        gzFile fp() { return m_fp; }
+
+    private:
+        gzFile m_fp;
+};
+
+/*
+ * Binary read the given (array of) object(s) from the compressed file.
+ * If the input file was not in gzip format, read() copies the objects number
+ * of bytes into the buffer.
+ * returns the number of uncompressed bytes actually read
+ * (0 for end of file, -1 for error).
+ */
+template <class T, class Items>
+inline int read(izstream& zs, T* x, Items items) {
+    return ::gzread(zs.fp(), x, items*sizeof(T));
+}
+
+/*
+ * Binary input with the '>' operator.
+ */
+template <class T>
+inline izstream& operator>(izstream& zs, T& x) {
+    ::gzread(zs.fp(), &x, sizeof(T));
+    return zs;
+}
+
+
+inline zstringlen::zstringlen(izstream& zs) {
+    zs > val.byte;
+    if (val.byte == 255) zs > val.word;
+    else val.word = val.byte;
+}
+
+/*
+ * Read length of string + the string with the '>' operator.
+ */
+inline izstream& operator>(izstream& zs, char* x) {
+    zstringlen len(zs);
+    ::gzread(zs.fp(), x, len.value());
+    x[len.value()] = '\0';
+    return zs;
+}
+
+inline char* read_string(izstream& zs) {
+    zstringlen len(zs);
+    char* x = new char[len.value()+1];
+    ::gzread(zs.fp(), x, len.value());
+    x[len.value()] = '\0';
+    return x;
+}
+
+// ----------------------------- ozstream -----------------------------
+
+class ozstream
+{
+    public:
+        ozstream() : m_fp(0), m_os(0) {
+        }
+        ozstream(FILE* fp, int level = Z_DEFAULT_COMPRESSION)
+            : m_fp(0), m_os(0) {
+            open(fp, level);
+        }
+        ozstream(const char* name, int level = Z_DEFAULT_COMPRESSION)
+            : m_fp(0), m_os(0) {
+            open(name, level);
+        }
+        ~ozstream() {
+            close();
+        }
+
+        /* Opens a gzip (.gz) file for writing.
+         * The compression level parameter should be in 0..9
+         * errno can be checked to distinguish two error cases
+         * (if errno is zero, the zlib error is Z_MEM_ERROR).
+         */
+        void open(const char* name, int level = Z_DEFAULT_COMPRESSION) {
+            char mode[4] = "wb\0";
+            if (level != Z_DEFAULT_COMPRESSION) mode[2] = '0'+level;
+            if (m_fp) close();
+            m_fp = ::gzopen(name, mode);
+        }
+
+        /* open from a FILE pointer.
+         */
+        void open(FILE* fp, int level = Z_DEFAULT_COMPRESSION) {
+            SET_BINARY_MODE(fp);
+            char mode[4] = "wb\0";
+            if (level != Z_DEFAULT_COMPRESSION) mode[2] = '0'+level;
+            if (m_fp) close();
+            m_fp = ::gzdopen(fileno(fp), mode);
+        }
+
+        /* Flushes all pending output if necessary, closes the compressed file
+         * and deallocates all the (de)compression state. The return value is
+         * the zlib error number (see function error() below).
+         */
+        int close() {
+            if (m_os) {
+                ::gzwrite(m_fp, m_os->str(), m_os->pcount());
+                delete[] m_os->str(); delete m_os; m_os = 0;
+            }
+            int r = ::gzclose(m_fp); m_fp = 0; return r;
+        }
+
+        /* Binary write the given number of bytes into the compressed file.
+         */
+        int write(const void* buf, size_t len) {
+            return ::gzwrite(m_fp, (voidp) buf, len);
+        }
+
+        /* Flushes all pending output into the compressed file. The parameter
+         * _flush is as in the deflate() function. The return value is the zlib
+         * error number (see function gzerror below). flush() returns Z_OK if
+         * the flush_ parameter is Z_FINISH and all output could be flushed.
+         * flush() should be called only when strictly necessary because it can
+         * degrade compression.
+         */
+        int flush(int _flush) {
+            os_flush();
+            return ::gzflush(m_fp, _flush);
+        }
+
+        /* Returns the error message for the last error which occurred on the
+         * given compressed file. errnum is set to zlib error number. If an
+         * error occurred in the file system and not in the compression library,
+         * errnum is set to Z_ERRNO and the application may consult errno
+         * to get the exact error code.
+         */
+        const char* error(int* errnum) {
+            return ::gzerror(m_fp, errnum);
+        }
+
+        gzFile fp() { return m_fp; }
+
+        ostream& os() {
+            if (m_os == 0) m_os = new ostrstream;
+            return *m_os;
+        }
+
+        void os_flush() {
+            if (m_os && m_os->pcount()>0) {
+                ostrstream* oss = new ostrstream;
+                oss->fill(m_os->fill());
+                oss->flags(m_os->flags());
+                oss->precision(m_os->precision());
+                oss->width(m_os->width());
+                ::gzwrite(m_fp, m_os->str(), m_os->pcount());
+                delete[] m_os->str(); delete m_os; m_os = oss;
+            }
+        }
+
+    private:
+        gzFile m_fp;
+        ostrstream* m_os;
+};
+
+/*
+ * Binary write the given (array of) object(s) into the compressed file.
+ * returns the number of uncompressed bytes actually written
+ * (0 in case of error).
+ */
+template <class T, class Items>
+inline int write(ozstream& zs, const T* x, Items items) {
+    return ::gzwrite(zs.fp(), (voidp) x, items*sizeof(T));
+}
+
+/*
+ * Binary output with the '<' operator.
+ */
+template <class T>
+inline ozstream& operator<(ozstream& zs, const T& x) {
+    ::gzwrite(zs.fp(), (voidp) &x, sizeof(T));
+    return zs;
+}
+
+inline zstringlen::zstringlen(ozstream& zs, const char* x) {
+    val.byte = 255;  val.word = ::strlen(x);
+    if (val.word < 255) zs < (val.byte = val.word);
+    else zs < val;
+}
+
+/*
+ * Write length of string + the string with the '<' operator.
+ */
+inline ozstream& operator<(ozstream& zs, const char* x) {
+    zstringlen len(zs, x);
+    ::gzwrite(zs.fp(), (voidp) x, len.value());
+    return zs;
+}
+
+#ifdef _MSC_VER
+inline ozstream& operator<(ozstream& zs, char* const& x) {
+    return zs < (const char*) x;
+}
+#endif
+
+/*
+ * Ascii write with the << operator;
+ */
+template <class T>
+inline ostream& operator<<(ozstream& zs, const T& x) {
+    zs.os_flush();
+    return zs.os() << x;
+}
+
+#endif
diff --git a/gs/zlib/contrib/iostream2/zstream_test.cpp b/gs/zlib/contrib/iostream2/zstream_test.cpp
new file mode 100644
index 000000000..6273f62d6
--- /dev/null
+++ b/gs/zlib/contrib/iostream2/zstream_test.cpp
@@ -0,0 +1,25 @@
+#include "zstream.h"
+#include <math.h>
+#include <stdlib.h>
+#include <iomanip.h>
+
+void main() {
+    char h[256] = "Hello";
+    char* g = "Goodbye";
+    ozstream out("temp.gz");
+    out < "This works well" < h < g;
+    out.close();
+
+    izstream in("temp.gz"); // read it back
+    char *x = read_string(in), *y = new char[256], z[256];
+    in > y > z;
+    in.close();
+    cout << x << endl << y << endl << z << endl;
+
+    out.open("temp.gz"); // try ascii output; zcat temp.gz to see the results
+    out << setw(50) << setfill('#') << setprecision(20) << x << endl << y << endl << z << endl;
+    out << z << endl << y << endl << x << endl;
+    out << 1.1234567890123456789 << endl;
+
+    delete[] x; delete[] y;
+}
diff --git a/gs/zlib/contrib/iostream3/README b/gs/zlib/contrib/iostream3/README
new file mode 100644
index 000000000..f7b319ab9
--- /dev/null
+++ b/gs/zlib/contrib/iostream3/README
@@ -0,0 +1,35 @@
+These classes provide a C++ stream interface to the zlib library. It allows you
+to do things like:
+
+  gzofstream outf("blah.gz");
+  outf << "These go into the gzip file " << 123 << endl;
+
+It does this by deriving a specialized stream buffer for gzipped files, which is
+the way Stroustrup would have done it. :->
+
+The gzifstream and gzofstream classes were originally written by Kevin Ruland
+and made available in the zlib contrib/iostream directory. The older version still
+compiles under gcc 2.xx, but not under gcc 3.xx, which sparked the development of
+this version.
+
+The new classes are as standard-compliant as possible, closely following the
+approach of the standard library's fstream classes. It compiles under gcc versions
+3.2 and 3.3, but not under gcc 2.xx. This is mainly due to changes in the standard
+library naming scheme. The new version of gzifstream/gzofstream/gzfilebuf differs
+from the previous one in the following respects:
+- added showmanyc
+- added setbuf, with support for unbuffered output via setbuf(0,0)
+- a few bug fixes of stream behavior
+- gzipped output file opened with default compression level instead of maximum level
+- setcompressionlevel()/strategy() members replaced by single setcompression()
+
+The code is provided "as is", with the permission to use, copy, modify, distribute
+and sell it for any purpose without fee.
+
+Ludwig Schwardt
+<schwardt@sun.ac.za>
+
+DSP Lab
+Electrical & Electronic Engineering Department
+University of Stellenbosch
+South Africa
diff --git a/gs/zlib/contrib/iostream3/TODO b/gs/zlib/contrib/iostream3/TODO
new file mode 100644
index 000000000..7032f97be
--- /dev/null
+++ b/gs/zlib/contrib/iostream3/TODO
@@ -0,0 +1,17 @@
+Possible upgrades to gzfilebuf:
+
+- The ability to do putback (e.g. putbackfail)
+
+- The ability to seek (zlib supports this, but could be slow/tricky)
+
+- Simultaneous read/write access (does it make sense?)
+
+- Support for ios_base::ate open mode
+
+- Locale support?
+
+- Check public interface to see which calls give problems
+  (due to dependence on library internals)
+
+- Override operator<<(ostream&, gzfilebuf*) to allow direct copying
+  of stream buffer to stream ( i.e. os << is.rdbuf(); )
diff --git a/gs/zlib/contrib/iostream3/test.cc b/gs/zlib/contrib/iostream3/test.cc
new file mode 100644
index 000000000..94235334f
--- /dev/null
+++ b/gs/zlib/contrib/iostream3/test.cc
@@ -0,0 +1,50 @@
+/*
+ * Test program for gzifstream and gzofstream
+ *
+ * by Ludwig Schwardt <schwardt@sun.ac.za>
+ * original version by Kevin Ruland <kevin@rodin.wustl.edu>
+ */
+
+#include "zfstream.h"
+#include <iostream>      // for cout
+
+int main() {
+
+  gzofstream outf;
+  gzifstream inf;
+  char buf[80];
+
+  outf.open("test1.txt.gz");
+  outf << "The quick brown fox sidestepped the lazy canine\n"
+       << 1.3 << "\nPlan " << 9 << std::endl;
+  outf.close();
+  std::cout << "Wrote the following message to 'test1.txt.gz' (check with zcat or zless):\n"
+            << "The quick brown fox sidestepped the lazy canine\n"
+            << 1.3 << "\nPlan " << 9 << std::endl;
+
+  std::cout << "\nReading 'test1.txt.gz' (buffered) produces:\n";
+  inf.open("test1.txt.gz");
+  while (inf.getline(buf,80,'\n')) {
+    std::cout << buf << "\t(" << inf.rdbuf()->in_avail() << " chars left in buffer)\n";
+  }
+  inf.close();
+
+  outf.rdbuf()->pubsetbuf(0,0);
+  outf.open("test2.txt.gz");
+  outf << setcompression(Z_NO_COMPRESSION)
+       << "The quick brown fox sidestepped the lazy canine\n"
+       << 1.3 << "\nPlan " << 9 << std::endl;
+  outf.close();
+  std::cout << "\nWrote the same message to 'test2.txt.gz' in uncompressed form";
+
+  std::cout << "\nReading 'test2.txt.gz' (unbuffered) produces:\n";
+  inf.rdbuf()->pubsetbuf(0,0);
+  inf.open("test2.txt.gz");
+  while (inf.getline(buf,80,'\n')) {
+    std::cout << buf << "\t(" << inf.rdbuf()->in_avail() << " chars left in buffer)\n";
+  }
+  inf.close();
+
+  return 0;
+
+}
diff --git a/gs/zlib/contrib/iostream3/zfstream.cc b/gs/zlib/contrib/iostream3/zfstream.cc
new file mode 100644
index 000000000..94eb93344
--- /dev/null
+++ b/gs/zlib/contrib/iostream3/zfstream.cc
@@ -0,0 +1,479 @@
+/*
+ * A C++ I/O streams interface to the zlib gz* functions
+ *
+ * by Ludwig Schwardt <schwardt@sun.ac.za>
+ * original version by Kevin Ruland <kevin@rodin.wustl.edu>
+ *
+ * This version is standard-compliant and compatible with gcc 3.x.
+ */
+
+#include "zfstream.h"
+#include <cstring>          // for strcpy, strcat, strlen (mode strings)
+#include <cstdio>           // for BUFSIZ
+
+// Internal buffer sizes (default and "unbuffered" versions)
+#define BIGBUFSIZE BUFSIZ
+#define SMALLBUFSIZE 1
+
+/*****************************************************************************/
+
+// Default constructor
+gzfilebuf::gzfilebuf()
+: file(NULL), io_mode(std::ios_base::openmode(0)), own_fd(false),
+  buffer(NULL), buffer_size(BIGBUFSIZE), own_buffer(true)
+{
+  // No buffers to start with
+  this->disable_buffer();
+}
+
+// Destructor
+gzfilebuf::~gzfilebuf()
+{
+  // Sync output buffer and close only if responsible for file
+  // (i.e. attached streams should be left open at this stage)
+  this->sync();
+  if (own_fd)
+    this->close();
+  // Make sure internal buffer is deallocated
+  this->disable_buffer();
+}
+
+// Set compression level and strategy
+int
+gzfilebuf::setcompression(int comp_level,
+                          int comp_strategy)
+{
+  return gzsetparams(file, comp_level, comp_strategy);
+}
+
+// Open gzipped file
+gzfilebuf*
+gzfilebuf::open(const char *name,
+                std::ios_base::openmode mode)
+{
+  // Fail if file already open
+  if (this->is_open())
+    return NULL;
+  // Don't support simultaneous read/write access (yet)
+  if ((mode & std::ios_base::in) && (mode & std::ios_base::out))
+    return NULL;
+
+  // Build mode string for gzopen and check it [27.8.1.3.2]
+  char char_mode[6] = "\0\0\0\0\0";
+  if (!this->open_mode(mode, char_mode))
+    return NULL;
+
+  // Attempt to open file
+  if ((file = gzopen(name, char_mode)) == NULL)
+    return NULL;
+
+  // On success, allocate internal buffer and set flags
+  this->enable_buffer();
+  io_mode = mode;
+  own_fd = true;
+  return this;
+}
+
+// Attach to gzipped file
+gzfilebuf*
+gzfilebuf::attach(int fd,
+                  std::ios_base::openmode mode)
+{
+  // Fail if file already open
+  if (this->is_open())
+    return NULL;
+  // Don't support simultaneous read/write access (yet)
+  if ((mode & std::ios_base::in) && (mode & std::ios_base::out))
+    return NULL;
+
+  // Build mode string for gzdopen and check it [27.8.1.3.2]
+  char char_mode[6] = "\0\0\0\0\0";
+  if (!this->open_mode(mode, char_mode))
+    return NULL;
+
+  // Attempt to attach to file
+  if ((file = gzdopen(fd, char_mode)) == NULL)
+    return NULL;
+
+  // On success, allocate internal buffer and set flags
+  this->enable_buffer();
+  io_mode = mode;
+  own_fd = false;
+  return this;
+}
+
+// Close gzipped file
+gzfilebuf*
+gzfilebuf::close()
+{
+  // Fail immediately if no file is open
+  if (!this->is_open())
+    return NULL;
+  // Assume success
+  gzfilebuf* retval = this;
+  // Attempt to sync and close gzipped file
+  if (this->sync() == -1)
+    retval = NULL;
+  if (gzclose(file) < 0)
+    retval = NULL;
+  // File is now gone anyway (postcondition [27.8.1.3.8])
+  file = NULL;
+  own_fd = false;
+  // Destroy internal buffer if it exists
+  this->disable_buffer();
+  return retval;
+}
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+// Convert int open mode to mode string
+bool
+gzfilebuf::open_mode(std::ios_base::openmode mode,
+                     char* c_mode) const
+{
+  bool testb = mode & std::ios_base::binary;
+  bool testi = mode & std::ios_base::in;
+  bool testo = mode & std::ios_base::out;
+  bool testt = mode & std::ios_base::trunc;
+  bool testa = mode & std::ios_base::app;
+
+  // Check for valid flag combinations - see [27.8.1.3.2] (Table 92)
+  // Original zfstream hardcoded the compression level to maximum here...
+  // Double the time for less than 1% size improvement seems
+  // excessive though - keeping it at the default level
+  // To change back, just append "9" to the next three mode strings
+  if (!testi && testo && !testt && !testa)
+    strcpy(c_mode, "w");
+  if (!testi && testo && !testt && testa)
+    strcpy(c_mode, "a");
+  if (!testi && testo && testt && !testa)
+    strcpy(c_mode, "w");
+  if (testi && !testo && !testt && !testa)
+    strcpy(c_mode, "r");
+  // No read/write mode yet
+//  if (testi && testo && !testt && !testa)
+//    strcpy(c_mode, "r+");
+//  if (testi && testo && testt && !testa)
+//    strcpy(c_mode, "w+");
+
+  // Mode string should be empty for invalid combination of flags
+  if (strlen(c_mode) == 0)
+    return false;
+  if (testb)
+    strcat(c_mode, "b");
+  return true;
+}
+
+// Determine number of characters in internal get buffer
+std::streamsize
+gzfilebuf::showmanyc()
+{
+  // Calls to underflow will fail if file not opened for reading
+  if (!this->is_open() || !(io_mode & std::ios_base::in))
+    return -1;
+  // Make sure get area is in use
+  if (this->gptr() && (this->gptr() < this->egptr()))
+    return std::streamsize(this->egptr() - this->gptr());
+  else
+    return 0;
+}
+
+// Fill get area from gzipped file
+gzfilebuf::int_type
+gzfilebuf::underflow()
+{
+  // If something is left in the get area by chance, return it
+  // (this shouldn't normally happen, as underflow is only supposed
+  // to be called when gptr >= egptr, but it serves as error check)
+  if (this->gptr() && (this->gptr() < this->egptr()))
+    return traits_type::to_int_type(*(this->gptr()));
+
+  // If the file hasn't been opened for reading, produce error
+  if (!this->is_open() || !(io_mode & std::ios_base::in))
+    return traits_type::eof();
+
+  // Attempt to fill internal buffer from gzipped file
+  // (buffer must be guaranteed to exist...)
+  int bytes_read = gzread(file, buffer, buffer_size);
+  // Indicates error or EOF
+  if (bytes_read <= 0)
+  {
+    // Reset get area
+    this->setg(buffer, buffer, buffer);
+    return traits_type::eof();
+  }
+  // Make all bytes read from file available as get area
+  this->setg(buffer, buffer, buffer + bytes_read);
+
+  // Return next character in get area
+  return traits_type::to_int_type(*(this->gptr()));
+}
+
+// Write put area to gzipped file
+gzfilebuf::int_type
+gzfilebuf::overflow(int_type c)
+{
+  // Determine whether put area is in use
+  if (this->pbase())
+  {
+    // Double-check pointer range
+    if (this->pptr() > this->epptr() || this->pptr() < this->pbase())
+      return traits_type::eof();
+    // Add extra character to buffer if not EOF
+    if (!traits_type::eq_int_type(c, traits_type::eof()))
+    {
+      *(this->pptr()) = traits_type::to_char_type(c);
+      this->pbump(1);
+    }
+    // Number of characters to write to file
+    int bytes_to_write = this->pptr() - this->pbase();
+    // Overflow doesn't fail if nothing is to be written
+    if (bytes_to_write > 0)
+    {
+      // If the file hasn't been opened for writing, produce error
+      if (!this->is_open() || !(io_mode & std::ios_base::out))
+        return traits_type::eof();
+      // If gzipped file won't accept all bytes written to it, fail
+      if (gzwrite(file, this->pbase(), bytes_to_write) != bytes_to_write)
+        return traits_type::eof();
+      // Reset next pointer to point to pbase on success
+      this->pbump(-bytes_to_write);
+    }
+  }
+  // Write extra character to file if not EOF
+  else if (!traits_type::eq_int_type(c, traits_type::eof()))
+  {
+    // If the file hasn't been opened for writing, produce error
+    if (!this->is_open() || !(io_mode & std::ios_base::out))
+      return traits_type::eof();
+    // Impromptu char buffer (allows "unbuffered" output)
+    char_type last_char = traits_type::to_char_type(c);
+    // If gzipped file won't accept this character, fail
+    if (gzwrite(file, &last_char, 1) != 1)
+      return traits_type::eof();
+  }
+
+  // If you got here, you have succeeded (even if c was EOF)
+  // The return value should therefore be non-EOF
+  if (traits_type::eq_int_type(c, traits_type::eof()))
+    return traits_type::not_eof(c);
+  else
+    return c;
+}
+
+// Assign new buffer
+std::streambuf*
+gzfilebuf::setbuf(char_type* p,
+                  std::streamsize n)
+{
+  // First make sure stuff is sync'ed, for safety
+  if (this->sync() == -1)
+    return NULL;
+  // If buffering is turned off on purpose via setbuf(0,0), still allocate one...
+  // "Unbuffered" only really refers to put [27.8.1.4.10], while get needs at
+  // least a buffer of size 1 (very inefficient though, therefore make it bigger?)
+  // This follows from [27.5.2.4.3]/12 (gptr needs to point at something, it seems)
+  if (!p || !n)
+  {
+    // Replace existing buffer (if any) with small internal buffer
+    this->disable_buffer();
+    buffer = NULL;
+    buffer_size = 0;
+    own_buffer = true;
+    this->enable_buffer();
+  }
+  else
+  {
+    // Replace existing buffer (if any) with external buffer
+    this->disable_buffer();
+    buffer = p;
+    buffer_size = n;
+    own_buffer = false;
+    this->enable_buffer();
+  }
+  return this;
+}
+
+// Write put area to gzipped file (i.e. ensures that put area is empty)
+int
+gzfilebuf::sync()
+{
+  return traits_type::eq_int_type(this->overflow(), traits_type::eof()) ? -1 : 0;
+}
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+// Allocate internal buffer
+void
+gzfilebuf::enable_buffer()
+{
+  // If internal buffer required, allocate one
+  if (own_buffer && !buffer)
+  {
+    // Check for buffered vs. "unbuffered"
+    if (buffer_size > 0)
+    {
+      // Allocate internal buffer
+      buffer = new char_type[buffer_size];
+      // Get area starts empty and will be expanded by underflow as need arises
+      this->setg(buffer, buffer, buffer);
+      // Setup entire internal buffer as put area.
+      // The one-past-end pointer actually points to the last element of the buffer,
+      // so that overflow(c) can safely add the extra character c to the sequence.
+      // These pointers remain in place for the duration of the buffer
+      this->setp(buffer, buffer + buffer_size - 1);
+    }
+    else
+    {
+      // Even in "unbuffered" case, (small?) get buffer is still required
+      buffer_size = SMALLBUFSIZE;
+      buffer = new char_type[buffer_size];
+      this->setg(buffer, buffer, buffer);
+      // "Unbuffered" means no put buffer
+      this->setp(0, 0);
+    }
+  }
+  else
+  {
+    // If buffer already allocated, reset buffer pointers just to make sure no
+    // stale chars are lying around
+    this->setg(buffer, buffer, buffer);
+    this->setp(buffer, buffer + buffer_size - 1);
+  }
+}
+
+// Destroy internal buffer
+void
+gzfilebuf::disable_buffer()
+{
+  // If internal buffer exists, deallocate it
+  if (own_buffer && buffer)
+  {
+    // Preserve unbuffered status by zeroing size
+    if (!this->pbase())
+      buffer_size = 0;
+    delete[] buffer;
+    buffer = NULL;
+    this->setg(0, 0, 0);
+    this->setp(0, 0);
+  }
+  else
+  {
+    // Reset buffer pointers to initial state if external buffer exists
+    this->setg(buffer, buffer, buffer);
+    if (buffer)
+      this->setp(buffer, buffer + buffer_size - 1);
+    else
+      this->setp(0, 0);
+  }
+}
+
+/*****************************************************************************/
+
+// Default constructor initializes stream buffer
+gzifstream::gzifstream()
+: std::istream(NULL), sb()
+{ this->init(&sb); }
+
+// Initialize stream buffer and open file
+gzifstream::gzifstream(const char* name,
+                       std::ios_base::openmode mode)
+: std::istream(NULL), sb()
+{
+  this->init(&sb);
+  this->open(name, mode);
+}
+
+// Initialize stream buffer and attach to file
+gzifstream::gzifstream(int fd,
+                       std::ios_base::openmode mode)
+: std::istream(NULL), sb()
+{
+  this->init(&sb);
+  this->attach(fd, mode);
+}
+
+// Open file and go into fail() state if unsuccessful
+void
+gzifstream::open(const char* name,
+                 std::ios_base::openmode mode)
+{
+  if (!sb.open(name, mode | std::ios_base::in))
+    this->setstate(std::ios_base::failbit);
+  else
+    this->clear();
+}
+
+// Attach to file and go into fail() state if unsuccessful
+void
+gzifstream::attach(int fd,
+                   std::ios_base::openmode mode)
+{
+  if (!sb.attach(fd, mode | std::ios_base::in))
+    this->setstate(std::ios_base::failbit);
+  else
+    this->clear();
+}
+
+// Close file
+void
+gzifstream::close()
+{
+  if (!sb.close())
+    this->setstate(std::ios_base::failbit);
+}
+
+/*****************************************************************************/
+
+// Default constructor initializes stream buffer
+gzofstream::gzofstream()
+: std::ostream(NULL), sb()
+{ this->init(&sb); }
+
+// Initialize stream buffer and open file
+gzofstream::gzofstream(const char* name,
+                       std::ios_base::openmode mode)
+: std::ostream(NULL), sb()
+{
+  this->init(&sb);
+  this->open(name, mode);
+}
+
+// Initialize stream buffer and attach to file
+gzofstream::gzofstream(int fd,
+                       std::ios_base::openmode mode)
+: std::ostream(NULL), sb()
+{
+  this->init(&sb);
+  this->attach(fd, mode);
+}
+
+// Open file and go into fail() state if unsuccessful
+void
+gzofstream::open(const char* name,
+                 std::ios_base::openmode mode)
+{
+  if (!sb.open(name, mode | std::ios_base::out))
+    this->setstate(std::ios_base::failbit);
+  else
+    this->clear();
+}
+
+// Attach to file and go into fail() state if unsuccessful
+void
+gzofstream::attach(int fd,
+                   std::ios_base::openmode mode)
+{
+  if (!sb.attach(fd, mode | std::ios_base::out))
+    this->setstate(std::ios_base::failbit);
+  else
+    this->clear();
+}
+
+// Close file
+void
+gzofstream::close()
+{
+  if (!sb.close())
+    this->setstate(std::ios_base::failbit);
+}
diff --git a/gs/zlib/contrib/iostream3/zfstream.h b/gs/zlib/contrib/iostream3/zfstream.h
new file mode 100644
index 000000000..8574479ae
--- /dev/null
+++ b/gs/zlib/contrib/iostream3/zfstream.h
@@ -0,0 +1,466 @@
+/*
+ * A C++ I/O streams interface to the zlib gz* functions
+ *
+ * by Ludwig Schwardt <schwardt@sun.ac.za>
+ * original version by Kevin Ruland <kevin@rodin.wustl.edu>
+ *
+ * This version is standard-compliant and compatible with gcc 3.x.
+ */
+
+#ifndef ZFSTREAM_H
+#define ZFSTREAM_H
+
+#include <istream>  // not iostream, since we don't need cin/cout
+#include <ostream>
+#include "zlib.h"
+
+/*****************************************************************************/
+
+/**
+ *  @brief  Gzipped file stream buffer class.
+ *
+ *  This class implements basic_filebuf for gzipped files. It doesn't yet support
+ *  seeking (allowed by zlib but slow/limited), putback and read/write access
+ *  (tricky). Otherwise, it attempts to be a drop-in replacement for the standard
+ *  file streambuf.
+*/
+class gzfilebuf : public std::streambuf
+{
+public:
+  //  Default constructor.
+  gzfilebuf();
+
+  //  Destructor.
+  virtual
+  ~gzfilebuf();
+
+  /**
+   *  @brief  Set compression level and strategy on the fly.
+   *  @param  comp_level  Compression level (see zlib.h for allowed values)
+   *  @param  comp_strategy  Compression strategy (see zlib.h for allowed values)
+   *  @return  Z_OK on success, Z_STREAM_ERROR otherwise.
+   *
+   *  Unfortunately, these parameters cannot be modified separately, as the
+   *  previous zfstream version assumed. Since the strategy is seldom changed,
+   *  it can default and setcompression(level) then becomes like the old
+   *  setcompressionlevel(level).
+  */
+  int
+  setcompression(int comp_level,
+                 int comp_strategy = Z_DEFAULT_STRATEGY);
+
+  /**
+   *  @brief  Check if file is open.
+   *  @return  True if file is open.
+  */
+  bool
+  is_open() const { return (file != NULL); }
+
+  /**
+   *  @brief  Open gzipped file.
+   *  @param  name  File name.
+   *  @param  mode  Open mode flags.
+   *  @return  @c this on success, NULL on failure.
+  */
+  gzfilebuf*
+  open(const char* name,
+       std::ios_base::openmode mode);
+
+  /**
+   *  @brief  Attach to already open gzipped file.
+   *  @param  fd  File descriptor.
+   *  @param  mode  Open mode flags.
+   *  @return  @c this on success, NULL on failure.
+  */
+  gzfilebuf*
+  attach(int fd,
+         std::ios_base::openmode mode);
+
+  /**
+   *  @brief  Close gzipped file.
+   *  @return  @c this on success, NULL on failure.
+  */
+  gzfilebuf*
+  close();
+
+protected:
+  /**
+   *  @brief  Convert ios open mode int to mode string used by zlib.
+   *  @return  True if valid mode flag combination.
+  */
+  bool
+  open_mode(std::ios_base::openmode mode,
+            char* c_mode) const;
+
+  /**
+   *  @brief  Number of characters available in stream buffer.
+   *  @return  Number of characters.
+   *
+   *  This indicates number of characters in get area of stream buffer.
+   *  These characters can be read without accessing the gzipped file.
+  */
+  virtual std::streamsize
+  showmanyc();
+
+  /**
+   *  @brief  Fill get area from gzipped file.
+   *  @return  First character in get area on success, EOF on error.
+   *
+   *  This actually reads characters from gzipped file to stream
+   *  buffer. Always buffered.
+  */
+  virtual int_type
+  underflow();
+
+  /**
+   *  @brief  Write put area to gzipped file.
+   *  @param  c  Extra character to add to buffer contents.
+   *  @return  Non-EOF on success, EOF on error.
+   *
+   *  This actually writes characters in stream buffer to
+   *  gzipped file. With unbuffered output this is done one
+   *  character at a time.
+  */
+  virtual int_type
+  overflow(int_type c = traits_type::eof());
+
+  /**
+   *  @brief  Installs external stream buffer.
+   *  @param  p  Pointer to char buffer.
+   *  @param  n  Size of external buffer.
+   *  @return  @c this on success, NULL on failure.
+   *
+   *  Call setbuf(0,0) to enable unbuffered output.
+  */
+  virtual std::streambuf*
+  setbuf(char_type* p,
+         std::streamsize n);
+
+  /**
+   *  @brief  Flush stream buffer to file.
+   *  @return  0 on success, -1 on error.
+   *
+   *  This calls underflow(EOF) to do the job.
+  */
+  virtual int
+  sync();
+
+//
+// Some future enhancements
+//
+//  virtual int_type uflow();
+//  virtual int_type pbackfail(int_type c = traits_type::eof());
+//  virtual pos_type
+//  seekoff(off_type off,
+//          std::ios_base::seekdir way,
+//          std::ios_base::openmode mode = std::ios_base::in|std::ios_base::out);
+//  virtual pos_type
+//  seekpos(pos_type sp,
+//          std::ios_base::openmode mode = std::ios_base::in|std::ios_base::out);
+
+private:
+  /**
+   *  @brief  Allocate internal buffer.
+   *
+   *  This function is safe to call multiple times. It will ensure
+   *  that a proper internal buffer exists if it is required. If the
+   *  buffer already exists or is external, the buffer pointers will be
+   *  reset to their original state.
+  */
+  void
+  enable_buffer();
+
+  /**
+   *  @brief  Destroy internal buffer.
+   *
+   *  This function is safe to call multiple times. It will ensure
+   *  that the internal buffer is deallocated if it exists. In any
+   *  case, it will also reset the buffer pointers.
+  */
+  void
+  disable_buffer();
+
+  /**
+   *  Underlying file pointer.
+  */
+  gzFile file;
+
+  /**
+   *  Mode in which file was opened.
+  */
+  std::ios_base::openmode io_mode;
+
+  /**
+   *  @brief  True if this object owns file descriptor.
+   *
+   *  This makes the class responsible for closing the file
+   *  upon destruction.
+  */
+  bool own_fd;
+
+  /**
+   *  @brief  Stream buffer.
+   *
+   *  For simplicity this remains allocated on the free store for the
+   *  entire life span of the gzfilebuf object, unless replaced by setbuf.
+  */
+  char_type* buffer;
+
+  /**
+   *  @brief  Stream buffer size.
+   *
+   *  Defaults to system default buffer size (typically 8192 bytes).
+   *  Modified by setbuf.
+  */
+  std::streamsize buffer_size;
+
+  /**
+   *  @brief  True if this object owns stream buffer.
+   *
+   *  This makes the class responsible for deleting the buffer
+   *  upon destruction.
+  */
+  bool own_buffer;
+};
+
+/*****************************************************************************/
+
+/**
+ *  @brief  Gzipped file input stream class.
+ *
+ *  This class implements ifstream for gzipped files. Seeking and putback
+ *  is not supported yet.
+*/
+class gzifstream : public std::istream
+{
+public:
+  //  Default constructor
+  gzifstream();
+
+  /**
+   *  @brief  Construct stream on gzipped file to be opened.
+   *  @param  name  File name.
+   *  @param  mode  Open mode flags (forced to contain ios::in).
+  */
+  explicit
+  gzifstream(const char* name,
+             std::ios_base::openmode mode = std::ios_base::in);
+
+  /**
+   *  @brief  Construct stream on already open gzipped file.
+   *  @param  fd    File descriptor.
+   *  @param  mode  Open mode flags (forced to contain ios::in).
+  */
+  explicit
+  gzifstream(int fd,
+             std::ios_base::openmode mode = std::ios_base::in);
+
+  /**
+   *  Obtain underlying stream buffer.
+  */
+  gzfilebuf*
+  rdbuf() const
+  { return const_cast<gzfilebuf*>(&sb); }
+
+  /**
+   *  @brief  Check if file is open.
+   *  @return  True if file is open.
+  */
+  bool
+  is_open() { return sb.is_open(); }
+
+  /**
+   *  @brief  Open gzipped file.
+   *  @param  name  File name.
+   *  @param  mode  Open mode flags (forced to contain ios::in).
+   *
+   *  Stream will be in state good() if file opens successfully;
+   *  otherwise in state fail(). This differs from the behavior of
+   *  ifstream, which never sets the state to good() and therefore
+   *  won't allow you to reuse the stream for a second file unless
+   *  you manually clear() the state. The choice is a matter of
+   *  convenience.
+  */
+  void
+  open(const char* name,
+       std::ios_base::openmode mode = std::ios_base::in);
+
+  /**
+   *  @brief  Attach to already open gzipped file.
+   *  @param  fd  File descriptor.
+   *  @param  mode  Open mode flags (forced to contain ios::in).
+   *
+   *  Stream will be in state good() if attach succeeded; otherwise
+   *  in state fail().
+  */
+  void
+  attach(int fd,
+         std::ios_base::openmode mode = std::ios_base::in);
+
+  /**
+   *  @brief  Close gzipped file.
+   *
+   *  Stream will be in state fail() if close failed.
+  */
+  void
+  close();
+
+private:
+  /**
+   *  Underlying stream buffer.
+  */
+  gzfilebuf sb;
+};
+
+/*****************************************************************************/
+
+/**
+ *  @brief  Gzipped file output stream class.
+ *
+ *  This class implements ofstream for gzipped files. Seeking and putback
+ *  is not supported yet.
+*/
+class gzofstream : public std::ostream
+{
+public:
+  //  Default constructor
+  gzofstream();
+
+  /**
+   *  @brief  Construct stream on gzipped file to be opened.
+   *  @param  name  File name.
+   *  @param  mode  Open mode flags (forced to contain ios::out).
+  */
+  explicit
+  gzofstream(const char* name,
+             std::ios_base::openmode mode = std::ios_base::out);
+
+  /**
+   *  @brief  Construct stream on already open gzipped file.
+   *  @param  fd    File descriptor.
+   *  @param  mode  Open mode flags (forced to contain ios::out).
+  */
+  explicit
+  gzofstream(int fd,
+             std::ios_base::openmode mode = std::ios_base::out);
+
+  /**
+   *  Obtain underlying stream buffer.
+  */
+  gzfilebuf*
+  rdbuf() const
+  { return const_cast<gzfilebuf*>(&sb); }
+
+  /**
+   *  @brief  Check if file is open.
+   *  @return  True if file is open.
+  */
+  bool
+  is_open() { return sb.is_open(); }
+
+  /**
+   *  @brief  Open gzipped file.
+   *  @param  name  File name.
+   *  @param  mode  Open mode flags (forced to contain ios::out).
+   *
+   *  Stream will be in state good() if file opens successfully;
+   *  otherwise in state fail(). This differs from the behavior of
+   *  ofstream, which never sets the state to good() and therefore
+   *  won't allow you to reuse the stream for a second file unless
+   *  you manually clear() the state. The choice is a matter of
+   *  convenience.
+  */
+  void
+  open(const char* name,
+       std::ios_base::openmode mode = std::ios_base::out);
+
+  /**
+   *  @brief  Attach to already open gzipped file.
+   *  @param  fd  File descriptor.
+   *  @param  mode  Open mode flags (forced to contain ios::out).
+   *
+   *  Stream will be in state good() if attach succeeded; otherwise
+   *  in state fail().
+  */
+  void
+  attach(int fd,
+         std::ios_base::openmode mode = std::ios_base::out);
+
+  /**
+   *  @brief  Close gzipped file.
+   *
+   *  Stream will be in state fail() if close failed.
+  */
+  void
+  close();
+
+private:
+  /**
+   *  Underlying stream buffer.
+  */
+  gzfilebuf sb;
+};
+
+/*****************************************************************************/
+
+/**
+ *  @brief  Gzipped file output stream manipulator class.
+ *
+ *  This class defines a two-argument manipulator for gzofstream. It is used
+ *  as base for the setcompression(int,int) manipulator.
+*/
+template<typename T1, typename T2>
+  class gzomanip2
+  {
+  public:
+    // Allows insertor to peek at internals
+    template <typename Ta, typename Tb>
+      friend gzofstream&
+      operator<<(gzofstream&,
+                 const gzomanip2<Ta,Tb>&);
+
+    // Constructor
+    gzomanip2(gzofstream& (*f)(gzofstream&, T1, T2),
+              T1 v1,
+              T2 v2);
+  private:
+    // Underlying manipulator function
+    gzofstream&
+    (*func)(gzofstream&, T1, T2);
+
+    // Arguments for manipulator function
+    T1 val1;
+    T2 val2;
+  };
+
+/*****************************************************************************/
+
+// Manipulator function thunks through to stream buffer
+inline gzofstream&
+setcompression(gzofstream &gzs, int l, int s = Z_DEFAULT_STRATEGY)
+{
+  (gzs.rdbuf())->setcompression(l, s);
+  return gzs;
+}
+
+// Manipulator constructor stores arguments
+template<typename T1, typename T2>
+  inline
+  gzomanip2<T1,T2>::gzomanip2(gzofstream &(*f)(gzofstream &, T1, T2),
+                              T1 v1,
+                              T2 v2)
+  : func(f), val1(v1), val2(v2)
+  { }
+
+// Insertor applies underlying manipulator function to stream
+template<typename T1, typename T2>
+  inline gzofstream&
+  operator<<(gzofstream& s, const gzomanip2<T1,T2>& m)
+  { return (*m.func)(s, m.val1, m.val2); }
+
+// Insert this onto stream to simplify setting of compression level
+inline gzomanip2<int,int>
+setcompression(int l, int s = Z_DEFAULT_STRATEGY)
+{ return gzomanip2<int,int>(&setcompression, l, s); }
+
+#endif // ZFSTREAM_H
diff --git a/gs/zlib/contrib/masm686/match.asm b/gs/zlib/contrib/masm686/match.asm
new file mode 100644
index 000000000..4b03a71ab
--- /dev/null
+++ b/gs/zlib/contrib/masm686/match.asm
@@ -0,0 +1,413 @@
+

+; match.asm -- Pentium-Pro optimized version of longest_match()

+;

+; Updated for zlib 1.1.3 and converted to MASM 6.1x

+; Copyright (C) 2000 Dan Higdon <hdan@kinesoft.com>

+;                    and Chuck Walbourn <chuckw@kinesoft.com>

+; Corrections by Cosmin Truta <cosmint@cs.ubbcluj.ro>

+;

+; This is free software; you can redistribute it and/or modify it

+; under the terms of the GNU General Public License.

+

+; Based on match.S

+; Written for zlib 1.1.2

+; Copyright (C) 1998 Brian Raiter <breadbox@muppetlabs.com>

+;

+; Modified by Gilles Vollant (2005) for add gzhead and gzindex

+

+	.686P

+	.MODEL	FLAT

+

+;===========================================================================

+; EQUATES

+;===========================================================================

+

+MAX_MATCH	EQU 258

+MIN_MATCH	EQU 3

+MIN_LOOKAHEAD	EQU (MAX_MATCH + MIN_MATCH + 1)

+MAX_MATCH_8	EQU ((MAX_MATCH + 7) AND (NOT 7))

+

+;===========================================================================

+; STRUCTURES

+;===========================================================================

+

+; This STRUCT assumes a 4-byte alignment

+

+DEFLATE_STATE	STRUCT

+ds_strm			dd ?

+ds_status		dd ?

+ds_pending_buf		dd ?

+ds_pending_buf_size	dd ?

+ds_pending_out		dd ?

+ds_pending		dd ?

+ds_wrap			dd ?

+; gzhead and gzindex are added in zlib 1.2.2.2 (see deflate.h)

+ds_gzhead               dd ?

+ds_gzindex              dd ?

+ds_data_type		db ?

+ds_method		db ?

+			db ?	; padding

+			db ?	; padding

+ds_last_flush		dd ?

+ds_w_size		dd ?	; used

+ds_w_bits		dd ?

+ds_w_mask		dd ?	; used

+ds_window		dd ?	; used

+ds_window_size		dd ?

+ds_prev			dd ?	; used

+ds_head			dd ?

+ds_ins_h		dd ?

+ds_hash_size		dd ?

+ds_hash_bits		dd ?

+ds_hash_mask		dd ?

+ds_hash_shift		dd ?

+ds_block_start		dd ?

+ds_match_length		dd ?	; used

+ds_prev_match		dd ?	; used

+ds_match_available	dd ?

+ds_strstart		dd ?	; used

+ds_match_start		dd ?	; used

+ds_lookahead		dd ?	; used

+ds_prev_length		dd ?	; used

+ds_max_chain_length	dd ?	; used

+ds_max_laxy_match	dd ?

+ds_level		dd ?

+ds_strategy		dd ?

+ds_good_match		dd ?	; used

+ds_nice_match		dd ?	; used

+

+; Don't need anymore of the struct for match

+DEFLATE_STATE	ENDS

+

+;===========================================================================

+; CODE

+;===========================================================================

+_TEXT	SEGMENT

+

+;---------------------------------------------------------------------------

+; match_init

+;---------------------------------------------------------------------------

+	ALIGN	4

+PUBLIC	_match_init

+_match_init	PROC

+	; no initialization needed

+	ret

+_match_init	ENDP

+

+;---------------------------------------------------------------------------

+; uInt longest_match(deflate_state *deflatestate, IPos curmatch)

+;---------------------------------------------------------------------------

+	ALIGN	4

+

+PUBLIC	_longest_match

+_longest_match	PROC

+

+; Since this code uses EBP for a scratch register, the stack frame must

+; be manually constructed and referenced relative to the ESP register.

+

+; Stack image

+; Variables

+chainlenwmask	=  0	; high word: current chain len

+			; low word: s->wmask

+window		=  4	; local copy of s->window

+windowbestlen	=  8	; s->window + bestlen

+scanend		= 12	; last two bytes of string

+scanstart	= 16	; first two bytes of string

+scanalign	= 20	; dword-misalignment of string

+nicematch	= 24	; a good enough match size

+bestlen		= 28	; size of best match so far

+scan		= 32	; ptr to string wanting match

+varsize		= 36	; number of bytes (also offset to last saved register)

+

+; Saved Registers (actually pushed into place)

+ebx_save	= 36

+edi_save	= 40

+esi_save	= 44

+ebp_save	= 48

+

+; Parameters

+retaddr		= 52

+deflatestate	= 56

+curmatch	= 60

+

+; Save registers that the compiler may be using

+	push	ebp

+	push	edi

+	push	esi

+	push	ebx

+

+; Allocate local variable space

+	sub	esp,varsize

+

+; Retrieve the function arguments. ecx will hold cur_match

+; throughout the entire function. edx will hold the pointer to the

+; deflate_state structure during the function's setup (before

+; entering the main loop).

+

+	mov	edx, [esp+deflatestate]

+ASSUME	edx:PTR DEFLATE_STATE

+

+	mov	ecx, [esp+curmatch]

+

+; uInt wmask = s->w_mask;

+; unsigned chain_length = s->max_chain_length;

+; if (s->prev_length >= s->good_match) {

+;     chain_length >>= 2;

+; }

+

+	mov	eax, [edx].ds_prev_length

+	mov	ebx, [edx].ds_good_match

+	cmp	eax, ebx

+	mov	eax, [edx].ds_w_mask

+	mov	ebx, [edx].ds_max_chain_length

+	jl	SHORT LastMatchGood

+	shr	ebx, 2

+LastMatchGood:

+

+; chainlen is decremented once beforehand so that the function can

+; use the sign flag instead of the zero flag for the exit test.

+; It is then shifted into the high word, to make room for the wmask

+; value, which it will always accompany.

+

+	dec	ebx

+	shl	ebx, 16

+	or	ebx, eax

+	mov	[esp+chainlenwmask], ebx

+

+; if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;

+

+	mov	eax, [edx].ds_nice_match

+	mov	ebx, [edx].ds_lookahead

+	cmp	ebx, eax

+	jl	SHORT LookaheadLess

+	mov	ebx, eax

+LookaheadLess:

+	mov	[esp+nicematch], ebx

+

+;/* register Bytef *scan = s->window + s->strstart;                     */

+

+	mov	esi, [edx].ds_window

+	mov	[esp+window], esi

+	mov	ebp, [edx].ds_strstart

+	lea	edi, [esi+ebp]

+	mov	[esp+scan],edi

+

+;/* Determine how many bytes the scan ptr is off from being             */

+;/* dword-aligned.                                                      */

+

+	mov	eax, edi

+	neg	eax

+	and	eax, 3

+	mov	[esp+scanalign], eax

+

+;/* IPos limit = s->strstart > (IPos)MAX_DIST(s) ?                      */

+;/*     s->strstart - (IPos)MAX_DIST(s) : NIL;                          */

+

+	mov	eax, [edx].ds_w_size

+	sub	eax, MIN_LOOKAHEAD

+	sub	ebp, eax

+	jg	SHORT LimitPositive

+	xor	ebp, ebp

+LimitPositive:

+

+;/* int best_len = s->prev_length;                                      */

+

+	mov	eax, [edx].ds_prev_length

+	mov	[esp+bestlen], eax

+

+;/* Store the sum of s->window + best_len in %esi locally, and in %esi. */

+

+	add	esi, eax

+	mov	[esp+windowbestlen], esi

+

+;/* register ush scan_start = *(ushf*)scan;                             */

+;/* register ush scan_end   = *(ushf*)(scan+best_len-1);                */

+;/* Posf *prev = s->prev;                                               */

+

+	movzx	ebx, WORD PTR[edi]

+	mov	[esp+scanstart], ebx

+	movzx	ebx, WORD PTR[eax+edi-1]

+	mov	[esp+scanend], ebx

+	mov	edi, [edx].ds_prev

+

+;/* Jump into the main loop.                                            */

+

+	mov	edx, [esp+chainlenwmask]

+	jmp	SHORT LoopEntry

+

+;/* do {

+; *     match = s->window + cur_match;

+; *     if (*(ushf*)(match+best_len-1) != scan_end ||

+; *         *(ushf*)match != scan_start) continue;

+; *     [...]

+; * } while ((cur_match = prev[cur_match & wmask]) > limit

+; *          && --chain_length != 0);

+; *

+; * Here is the inner loop of the function. The function will spend the

+; * majority of its time in this loop, and majority of that time will

+; * be spent in the first ten instructions.

+; *

+; * Within this loop:

+; * %ebx = scanend

+; * %ecx = curmatch

+; * %edx = chainlenwmask - i.e., ((chainlen << 16) | wmask)

+; * %esi = windowbestlen - i.e., (window + bestlen)

+; * %edi = prev

+; * %ebp = limit

+; */

+

+	ALIGN	4

+LookupLoop:

+	and	ecx, edx

+	movzx	ecx, WORD PTR[edi+ecx*2]

+	cmp	ecx, ebp

+	jbe	LeaveNow

+	sub	edx, 000010000H

+	js	LeaveNow

+

+LoopEntry:

+	movzx	eax, WORD PTR[esi+ecx-1]

+	cmp	eax, ebx

+	jnz	SHORT LookupLoop

+

+	mov	eax, [esp+window]

+	movzx	eax, WORD PTR[eax+ecx]

+	cmp	eax, [esp+scanstart]

+	jnz	SHORT LookupLoop

+

+;/* Store the current value of chainlen.                                */

+

+	mov	[esp+chainlenwmask], edx

+

+;/* Point %edi to the string under scrutiny, and %esi to the string we  */

+;/* are hoping to match it up with. In actuality, %esi and %edi are     */

+;/* both pointed (MAX_MATCH_8 - scanalign) bytes ahead, and %edx is     */

+;/* initialized to -(MAX_MATCH_8 - scanalign).                          */

+

+	mov	esi, [esp+window]

+	mov	edi, [esp+scan]

+	add	esi, ecx

+	mov	eax, [esp+scanalign]

+	mov	edx, -MAX_MATCH_8

+	lea	edi, [edi+eax+MAX_MATCH_8]

+	lea	esi, [esi+eax+MAX_MATCH_8]

+

+;/* Test the strings for equality, 8 bytes at a time. At the end,

+; * adjust %edx so that it is offset to the exact byte that mismatched.

+; *

+; * We already know at this point that the first three bytes of the

+; * strings match each other, and they can be safely passed over before

+; * starting the compare loop. So what this code does is skip over 0-3

+; * bytes, as much as necessary in order to dword-align the %edi

+; * pointer. (%esi will still be misaligned three times out of four.)

+; *

+; * It should be confessed that this loop usually does not represent

+; * much of the total running time. Replacing it with a more

+; * straightforward "rep cmpsb" would not drastically degrade

+; * performance.

+; */

+

+LoopCmps:

+	mov	eax, DWORD PTR[esi+edx]

+	xor	eax, DWORD PTR[edi+edx]

+	jnz	SHORT LeaveLoopCmps

+

+	mov	eax, DWORD PTR[esi+edx+4]

+	xor	eax, DWORD PTR[edi+edx+4]

+	jnz	SHORT LeaveLoopCmps4

+

+	add	edx, 8

+	jnz	SHORT LoopCmps

+	jmp	LenMaximum

+	ALIGN	4

+

+LeaveLoopCmps4:

+	add	edx, 4

+

+LeaveLoopCmps:

+	test	eax, 00000FFFFH

+	jnz	SHORT LenLower

+

+	add	edx, 2

+	shr	eax, 16

+

+LenLower:

+	sub	al, 1

+	adc	edx, 0

+

+;/* Calculate the length of the match. If it is longer than MAX_MATCH,  */

+;/* then automatically accept it as the best possible match and leave.  */

+

+	lea	eax, [edi+edx]

+	mov	edi, [esp+scan]

+	sub	eax, edi

+	cmp	eax, MAX_MATCH

+	jge	SHORT LenMaximum

+

+;/* If the length of the match is not longer than the best match we     */

+;/* have so far, then forget it and return to the lookup loop.          */

+

+	mov	edx, [esp+deflatestate]

+	mov	ebx, [esp+bestlen]

+	cmp	eax, ebx

+	jg	SHORT LongerMatch

+	mov	esi, [esp+windowbestlen]

+	mov	edi, [edx].ds_prev

+	mov	ebx, [esp+scanend]

+	mov	edx, [esp+chainlenwmask]

+	jmp	LookupLoop

+	ALIGN	4

+

+;/*         s->match_start = cur_match;                                 */

+;/*         best_len = len;                                             */

+;/*         if (len >= nice_match) break;                               */

+;/*         scan_end = *(ushf*)(scan+best_len-1);                       */

+

+LongerMatch:

+	mov	ebx, [esp+nicematch]

+	mov	[esp+bestlen], eax

+	mov	[edx].ds_match_start, ecx

+	cmp	eax, ebx

+	jge	SHORT LeaveNow

+	mov	esi, [esp+window]

+	add	esi, eax

+	mov	[esp+windowbestlen], esi

+	movzx	ebx, WORD PTR[edi+eax-1]

+	mov	edi, [edx].ds_prev

+	mov	[esp+scanend], ebx

+	mov	edx, [esp+chainlenwmask]

+	jmp	LookupLoop

+	ALIGN	4

+

+;/* Accept the current string, with the maximum possible length.        */

+

+LenMaximum:

+	mov	edx, [esp+deflatestate]

+	mov	DWORD PTR[esp+bestlen], MAX_MATCH

+	mov	[edx].ds_match_start, ecx

+

+;/* if ((uInt)best_len <= s->lookahead) return (uInt)best_len;          */

+;/* return s->lookahead;                                                */

+

+LeaveNow:

+	mov	edx, [esp+deflatestate]

+	mov	ebx, [esp+bestlen]

+	mov	eax, [edx].ds_lookahead

+	cmp	ebx, eax

+	jg	SHORT LookaheadRet

+	mov	eax, ebx

+LookaheadRet:

+

+; Restore the stack and return from whence we came.

+

+	add	esp, varsize

+	pop	ebx

+	pop	esi

+	pop	edi

+	pop	ebp

+	ret

+

+_longest_match	ENDP

+

+_TEXT	ENDS

+END

diff --git a/gs/zlib/contrib/masmx64/bld_ml64.bat b/gs/zlib/contrib/masmx64/bld_ml64.bat
new file mode 100644
index 000000000..8f9343d0a
--- /dev/null
+++ b/gs/zlib/contrib/masmx64/bld_ml64.bat
@@ -0,0 +1,2 @@
+ml64.exe /Flinffasx64 /c /Zi inffasx64.asm

+ml64.exe /Flgvmat64   /c /Zi gvmat64.asm

diff --git a/gs/zlib/contrib/masmx64/gvmat64.asm b/gs/zlib/contrib/masmx64/gvmat64.asm
new file mode 100644
index 000000000..790d65554
--- /dev/null
+++ b/gs/zlib/contrib/masmx64/gvmat64.asm
@@ -0,0 +1,513 @@
+;uInt longest_match_x64(

+;    deflate_state *s,

+;    IPos cur_match);                             /* current match */

+

+; gvmat64.asm -- Asm portion of the optimized longest_match for 32 bits x86

+; Copyright (C) 1995-2005 Jean-loup Gailly, Brian Raiter and Gilles Vollant.

+;

+; File written by Gilles Vollant, by converting to assembly the longest_match

+;  from Jean-loup Gailly in deflate.c of zLib and infoZip zip.

+;

+;  and by taking inspiration on asm686 with masm, optimised assembly code

+;        from Brian Raiter, written 1998

+;

+;         http://www.zlib.net

+;         http://www.winimage.com/zLibDll

+;         http://www.muppetlabs.com/~breadbox/software/assembly.html

+;

+; to compile this file for infozip Zip, I use option:

+;   ml64.exe /Flgvmat64 /c /Zi /DINFOZIP gvmat64.asm

+;

+; to compile this file for zLib, I use option:

+;   ml64.exe /Flgvmat64 /c /Zi gvmat64.asm

+; Be carrefull to adapt zlib1222add below to your version of zLib

+;   (if you use a version of zLib before 1.0.4 or after 1.2.2.2, change

+;    value of zlib1222add later)

+;

+; This file compile with Microsoft Macro Assembler (x64) for AMD64

+;

+;   ml64.exe is given with Visual Studio 2005 and Windows 2003 server DDK

+;

+;   (you can get Windows 2003 server DDK with ml64 and cl for AMD64 from

+;      http://www.microsoft.com/whdc/devtools/ddk/default.mspx for low price)

+;

+

+

+;uInt longest_match(s, cur_match)

+;    deflate_state *s;

+;    IPos cur_match;                             /* current match */

+.code

+longest_match PROC

+

+

+;LocalVarsSize   equ 88

+ LocalVarsSize   equ 72

+

+; register used : rax,rbx,rcx,rdx,rsi,rdi,r8,r9,r10,r11,r12

+; free register :  r14,r15

+; register can be saved : rsp

+

+ chainlenwmask   equ  rsp + 8 - LocalVarsSize    ; high word: current chain len

+                                                 ; low word: s->wmask

+;window          equ  rsp + xx - LocalVarsSize   ; local copy of s->window ; stored in r10

+;windowbestlen   equ  rsp + xx - LocalVarsSize   ; s->window + bestlen , use r10+r11

+;scanstart       equ  rsp + xx - LocalVarsSize   ; first two bytes of string ; stored in r12w

+;scanend         equ  rsp + xx - LocalVarsSize   ; last two bytes of string use ebx

+;scanalign       equ  rsp + xx - LocalVarsSize   ; dword-misalignment of string r13

+;bestlen         equ  rsp + xx - LocalVarsSize   ; size of best match so far -> r11d

+;scan            equ  rsp + xx - LocalVarsSize   ; ptr to string wanting match -> r9

+IFDEF INFOZIP

+ELSE

+ nicematch       equ  (rsp + 16 - LocalVarsSize) ; a good enough match size

+ENDIF

+

+save_rdi        equ  rsp + 24 - LocalVarsSize

+save_rsi        equ  rsp + 32 - LocalVarsSize

+save_rbx        equ  rsp + 40 - LocalVarsSize

+save_rbp        equ  rsp + 48 - LocalVarsSize

+save_r12        equ  rsp + 56 - LocalVarsSize

+save_r13        equ  rsp + 64 - LocalVarsSize

+;save_r14        equ  rsp + 72 - LocalVarsSize

+;save_r15        equ  rsp + 80 - LocalVarsSize

+

+

+

+;  all the +4 offsets are due to the addition of pending_buf_size (in zlib

+;  in the deflate_state structure since the asm code was first written

+;  (if you compile with zlib 1.0.4 or older, remove the +4).

+;  Note : these value are good with a 8 bytes boundary pack structure

+

+

+    MAX_MATCH           equ     258

+    MIN_MATCH           equ     3

+    MIN_LOOKAHEAD       equ     (MAX_MATCH+MIN_MATCH+1)

+

+

+;;; Offsets for fields in the deflate_state structure. These numbers

+;;; are calculated from the definition of deflate_state, with the

+;;; assumption that the compiler will dword-align the fields. (Thus,

+;;; changing the definition of deflate_state could easily cause this

+;;; program to crash horribly, without so much as a warning at

+;;; compile time. Sigh.)

+

+;  all the +zlib1222add offsets are due to the addition of fields

+;  in zlib in the deflate_state structure since the asm code was first written

+;  (if you compile with zlib 1.0.4 or older, use "zlib1222add equ (-4)").

+;  (if you compile with zlib between 1.0.5 and 1.2.2.1, use "zlib1222add equ 0").

+;  if you compile with zlib 1.2.2.2 or later , use "zlib1222add equ 8").

+

+

+IFDEF INFOZIP

+

+_DATA   SEGMENT

+COMM    window_size:DWORD

+; WMask ; 7fff

+COMM    window:BYTE:010040H

+COMM    prev:WORD:08000H

+; MatchLen : unused

+; PrevMatch : unused

+COMM    strstart:DWORD

+COMM    match_start:DWORD

+; Lookahead : ignore

+COMM    prev_length:DWORD ; PrevLen

+COMM    max_chain_length:DWORD

+COMM    good_match:DWORD

+COMM    nice_match:DWORD

+prev_ad equ OFFSET prev

+window_ad equ OFFSET window

+nicematch equ nice_match

+_DATA ENDS

+WMask equ 07fffh

+

+ELSE

+

+  IFNDEF zlib1222add

+    zlib1222add equ 8

+  ENDIF

+dsWSize         equ 56+zlib1222add+(zlib1222add/2)

+dsWMask         equ 64+zlib1222add+(zlib1222add/2)

+dsWindow        equ 72+zlib1222add

+dsPrev          equ 88+zlib1222add

+dsMatchLen      equ 128+zlib1222add

+dsPrevMatch     equ 132+zlib1222add

+dsStrStart      equ 140+zlib1222add

+dsMatchStart    equ 144+zlib1222add

+dsLookahead     equ 148+zlib1222add

+dsPrevLen       equ 152+zlib1222add

+dsMaxChainLen   equ 156+zlib1222add

+dsGoodMatch     equ 172+zlib1222add

+dsNiceMatch     equ 176+zlib1222add

+

+window_size     equ [ rcx + dsWSize]

+WMask           equ [ rcx + dsWMask]

+window_ad       equ [ rcx + dsWindow]

+prev_ad         equ [ rcx + dsPrev]

+strstart        equ [ rcx + dsStrStart]

+match_start     equ [ rcx + dsMatchStart]

+Lookahead       equ [ rcx + dsLookahead] ; 0ffffffffh on infozip

+prev_length     equ [ rcx + dsPrevLen]

+max_chain_length equ [ rcx + dsMaxChainLen]

+good_match      equ [ rcx + dsGoodMatch]

+nice_match      equ [ rcx + dsNiceMatch]

+ENDIF

+

+; parameter 1 in r8(deflate state s), param 2 in rdx (cur match)

+

+; see http://weblogs.asp.net/oldnewthing/archive/2004/01/14/58579.aspx and

+; http://msdn.microsoft.com/library/en-us/kmarch/hh/kmarch/64bitAMD_8e951dd2-ee77-4728-8702-55ce4b5dd24a.xml.asp

+;

+; All registers must be preserved across the call, except for

+;   rax, rcx, rdx, r8, r9, r10, and r11, which are scratch.

+

+

+

+;;; Save registers that the compiler may be using, and adjust esp to

+;;; make room for our stack frame.

+

+

+;;; Retrieve the function arguments. r8d will hold cur_match

+;;; throughout the entire function. edx will hold the pointer to the

+;;; deflate_state structure during the function's setup (before

+;;; entering the main loop.

+

+; parameter 1 in rcx (deflate_state* s), param 2 in edx -> r8 (cur match)

+

+; this clear high 32 bits of r8, which can be garbage in both r8 and rdx

+

+        mov [save_rdi],rdi

+        mov [save_rsi],rsi

+        mov [save_rbx],rbx

+        mov [save_rbp],rbp

+IFDEF INFOZIP

+        mov r8d,ecx

+ELSE

+        mov r8d,edx

+ENDIF

+        mov [save_r12],r12

+        mov [save_r13],r13

+;        mov [save_r14],r14

+;        mov [save_r15],r15

+

+

+;;; uInt wmask = s->w_mask;

+;;; unsigned chain_length = s->max_chain_length;

+;;; if (s->prev_length >= s->good_match) {

+;;;     chain_length >>= 2;

+;;; }

+

+        mov edi, prev_length

+        mov esi, good_match

+        mov eax, WMask

+        mov ebx, max_chain_length

+        cmp edi, esi

+        jl  LastMatchGood

+        shr ebx, 2

+LastMatchGood:

+

+;;; chainlen is decremented once beforehand so that the function can

+;;; use the sign flag instead of the zero flag for the exit test.

+;;; It is then shifted into the high word, to make room for the wmask

+;;; value, which it will always accompany.

+

+        dec ebx

+        shl ebx, 16

+        or  ebx, eax

+

+;;; on zlib only

+;;; if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;

+

+IFDEF INFOZIP

+        mov [chainlenwmask], ebx

+; on infozip nice_match = [nice_match]

+ELSE

+        mov eax, nice_match

+        mov [chainlenwmask], ebx

+        mov r10d, Lookahead

+        cmp r10d, eax

+        cmovnl r10d, eax

+        mov [nicematch],r10d

+ENDIF

+

+;;; register Bytef *scan = s->window + s->strstart;

+        mov r10, window_ad

+        mov ebp, strstart

+        lea r13, [r10 + rbp]

+

+;;; Determine how many bytes the scan ptr is off from being

+;;; dword-aligned.

+

+         mov r9,r13

+         neg r13

+         and r13,3

+

+;;; IPos limit = s->strstart > (IPos)MAX_DIST(s) ?

+;;;     s->strstart - (IPos)MAX_DIST(s) : NIL;

+IFDEF INFOZIP

+        mov eax,07efah ; MAX_DIST = (WSIZE-MIN_LOOKAHEAD) (0x8000-(3+8+1))

+ELSE

+        mov eax, window_size

+        sub eax, MIN_LOOKAHEAD

+ENDIF

+        xor edi,edi

+        sub ebp, eax

+

+        mov r11d, prev_length

+

+        cmovng ebp,edi

+

+;;; int best_len = s->prev_length;

+

+

+;;; Store the sum of s->window + best_len in esi locally, and in esi.

+

+       lea  rsi,[r10+r11]

+

+;;; register ush scan_start = *(ushf*)scan;

+;;; register ush scan_end   = *(ushf*)(scan+best_len-1);

+;;; Posf *prev = s->prev;

+

+        movzx r12d,word ptr [r9]

+        movzx ebx, word ptr [r9 + r11 - 1]

+

+        mov rdi, prev_ad

+

+;;; Jump into the main loop.

+

+        mov edx, [chainlenwmask]

+

+        cmp bx,word ptr [rsi + r8 - 1]

+        jz  LookupLoopIsZero

+

+LookupLoop1:

+        and r8d, edx

+

+        movzx   r8d, word ptr [rdi + r8*2]

+        cmp r8d, ebp

+        jbe LeaveNow

+        sub edx, 00010000h

+        js  LeaveNow

+

+LoopEntry1:

+        cmp bx,word ptr [rsi + r8 - 1]

+        jz  LookupLoopIsZero

+

+LookupLoop2:

+        and r8d, edx

+

+        movzx   r8d, word ptr [rdi + r8*2]

+        cmp r8d, ebp

+        jbe LeaveNow

+        sub edx, 00010000h

+        js  LeaveNow

+

+LoopEntry2:

+        cmp bx,word ptr [rsi + r8 - 1]

+        jz  LookupLoopIsZero

+

+LookupLoop4:

+        and r8d, edx

+

+        movzx   r8d, word ptr [rdi + r8*2]

+        cmp r8d, ebp

+        jbe LeaveNow

+        sub edx, 00010000h

+        js  LeaveNow

+

+LoopEntry4:

+

+        cmp bx,word ptr [rsi + r8 - 1]

+        jnz LookupLoop1

+        jmp LookupLoopIsZero

+

+

+;;; do {

+;;;     match = s->window + cur_match;

+;;;     if (*(ushf*)(match+best_len-1) != scan_end ||

+;;;         *(ushf*)match != scan_start) continue;

+;;;     [...]

+;;; } while ((cur_match = prev[cur_match & wmask]) > limit

+;;;          && --chain_length != 0);

+;;;

+;;; Here is the inner loop of the function. The function will spend the

+;;; majority of its time in this loop, and majority of that time will

+;;; be spent in the first ten instructions.

+;;;

+;;; Within this loop:

+;;; ebx = scanend

+;;; r8d = curmatch

+;;; edx = chainlenwmask - i.e., ((chainlen << 16) | wmask)

+;;; esi = windowbestlen - i.e., (window + bestlen)

+;;; edi = prev

+;;; ebp = limit

+

+LookupLoop:

+        and r8d, edx

+

+        movzx   r8d, word ptr [rdi + r8*2]

+        cmp r8d, ebp

+        jbe LeaveNow

+        sub edx, 00010000h

+        js  LeaveNow

+

+LoopEntry:

+

+        cmp bx,word ptr [rsi + r8 - 1]

+        jnz LookupLoop1

+LookupLoopIsZero:

+        cmp     r12w, word ptr [r10 + r8]

+        jnz LookupLoop1

+

+

+;;; Store the current value of chainlen.

+        mov [chainlenwmask], edx

+

+;;; Point edi to the string under scrutiny, and esi to the string we

+;;; are hoping to match it up with. In actuality, esi and edi are

+;;; both pointed (MAX_MATCH_8 - scanalign) bytes ahead, and edx is

+;;; initialized to -(MAX_MATCH_8 - scanalign).

+

+        lea rsi,[r8+r10]

+        mov rdx, 0fffffffffffffef8h; -(MAX_MATCH_8)

+        lea rsi, [rsi + r13 + 0108h] ;MAX_MATCH_8]

+        lea rdi, [r9 + r13 + 0108h] ;MAX_MATCH_8]

+

+        prefetcht1 [rsi+rdx]

+        prefetcht1 [rdi+rdx]

+

+

+;;; Test the strings for equality, 8 bytes at a time. At the end,

+;;; adjust rdx so that it is offset to the exact byte that mismatched.

+;;;

+;;; We already know at this point that the first three bytes of the

+;;; strings match each other, and they can be safely passed over before

+;;; starting the compare loop. So what this code does is skip over 0-3

+;;; bytes, as much as necessary in order to dword-align the edi

+;;; pointer. (rsi will still be misaligned three times out of four.)

+;;;

+;;; It should be confessed that this loop usually does not represent

+;;; much of the total running time. Replacing it with a more

+;;; straightforward "rep cmpsb" would not drastically degrade

+;;; performance.

+

+

+LoopCmps:

+        mov rax, [rsi + rdx]

+        xor rax, [rdi + rdx]

+        jnz LeaveLoopCmps

+

+        mov rax, [rsi + rdx + 8]

+        xor rax, [rdi + rdx + 8]

+        jnz LeaveLoopCmps8

+

+

+        mov rax, [rsi + rdx + 8+8]

+        xor rax, [rdi + rdx + 8+8]

+        jnz LeaveLoopCmps16

+

+        add rdx,8+8+8

+

+        jmp short LoopCmps

+LeaveLoopCmps16: add rdx,8

+LeaveLoopCmps8: add rdx,8

+LeaveLoopCmps:

+

+        test    eax, 0000FFFFh

+        jnz LenLower

+

+        test eax,0ffffffffh

+

+        jnz LenLower32

+

+        add rdx,4

+        shr rax,32

+        or ax,ax

+        jnz LenLower

+

+LenLower32:

+        shr eax,16

+        add rdx,2

+LenLower:   sub al, 1

+        adc rdx, 0

+;;; Calculate the length of the match. If it is longer than MAX_MATCH,

+;;; then automatically accept it as the best possible match and leave.

+

+        lea rax, [rdi + rdx]

+        sub rax, r9

+        cmp eax, MAX_MATCH

+        jge LenMaximum

+

+;;; If the length of the match is not longer than the best match we

+;;; have so far, then forget it and return to the lookup loop.

+;///////////////////////////////////

+

+        cmp eax, r11d

+        jg  LongerMatch

+

+        lea rsi,[r10+r11]

+

+        mov rdi, prev_ad

+        mov edx, [chainlenwmask]

+        jmp LookupLoop

+

+;;;         s->match_start = cur_match;

+;;;         best_len = len;

+;;;         if (len >= nice_match) break;

+;;;         scan_end = *(ushf*)(scan+best_len-1);

+

+LongerMatch:

+        mov r11d, eax

+        mov match_start, r8d

+        cmp eax, [nicematch]

+        jge LeaveNow

+

+        lea rsi,[r10+rax]

+

+        movzx   ebx, word ptr [r9 + rax - 1]

+        mov rdi, prev_ad

+        mov edx, [chainlenwmask]

+        jmp LookupLoop

+

+;;; Accept the current string, with the maximum possible length.

+

+LenMaximum:

+        mov r11d,MAX_MATCH

+        mov match_start, r8d

+

+;;; if ((uInt)best_len <= s->lookahead) return (uInt)best_len;

+;;; return s->lookahead;

+

+LeaveNow:

+IFDEF INFOZIP

+        mov eax,r11d

+ELSE

+        mov eax, Lookahead

+        cmp r11d, eax

+        cmovng eax, r11d

+ENDIF

+

+;;; Restore the stack and return from whence we came.

+

+

+        mov rsi,[save_rsi]

+        mov rdi,[save_rdi]

+        mov rbx,[save_rbx]

+        mov rbp,[save_rbp]

+        mov r12,[save_r12]

+        mov r13,[save_r13]

+;        mov r14,[save_r14]

+;        mov r15,[save_r15]

+

+

+        ret 0

+; please don't remove this string !

+; Your can freely use gvmat64 in any free or commercial app

+; but it is far better don't remove the string in the binary!

+    db     0dh,0ah,"asm686 with masm, optimised assembly code from Brian Raiter, written 1998, converted to amd 64 by Gilles Vollant 2005",0dh,0ah,0

+longest_match   ENDP

+

+match_init PROC

+  ret 0

+match_init ENDP

+

+

+END

diff --git a/gs/zlib/contrib/masmx64/gvmat64.obj b/gs/zlib/contrib/masmx64/gvmat64.obj
new file mode 100644
index 000000000..a49ca029c
--- /dev/null
+++ b/gs/zlib/contrib/masmx64/gvmat64.obj
diff --git a/gs/zlib/contrib/masmx64/inffas8664.c b/gs/zlib/contrib/masmx64/inffas8664.c
new file mode 100644
index 000000000..3af764de9
--- /dev/null
+++ b/gs/zlib/contrib/masmx64/inffas8664.c
@@ -0,0 +1,186 @@
+/* inffas8664.c is a hand tuned assembler version of inffast.c - fast decoding

+ * version for AMD64 on Windows using Microsoft C compiler

+ *

+ * Copyright (C) 1995-2003 Mark Adler

+ * For conditions of distribution and use, see copyright notice in zlib.h

+ *

+ * Copyright (C) 2003 Chris Anderson <christop@charm.net>

+ * Please use the copyright conditions above.

+ *

+ * 2005 - Adaptation to Microsoft C Compiler for AMD64 by Gilles Vollant

+ *

+ * inffas8664.c call function inffas8664fnc in inffasx64.asm

+ *  inffasx64.asm is automatically convert from AMD64 portion of inffas86.c

+ *

+ * Dec-29-2003 -- I added AMD64 inflate asm support.  This version is also

+ * slightly quicker on x86 systems because, instead of using rep movsb to copy

+ * data, it uses rep movsw, which moves data in 2-byte chunks instead of single

+ * bytes.  I've tested the AMD64 code on a Fedora Core 1 + the x86_64 updates

+ * from http://fedora.linux.duke.edu/fc1_x86_64

+ * which is running on an Athlon 64 3000+ / Gigabyte GA-K8VT800M system with

+ * 1GB ram.  The 64-bit version is about 4% faster than the 32-bit version,

+ * when decompressing mozilla-source-1.3.tar.gz.

+ *

+ * Mar-13-2003 -- Most of this is derived from inffast.S which is derived from

+ * the gcc -S output of zlib-1.2.0/inffast.c.  Zlib-1.2.0 is in beta release at

+ * the moment.  I have successfully compiled and tested this code with gcc2.96,

+ * gcc3.2, icc5.0, msvc6.0.  It is very close to the speed of inffast.S

+ * compiled with gcc -DNO_MMX, but inffast.S is still faster on the P3 with MMX

+ * enabled.  I will attempt to merge the MMX code into this version.  Newer

+ * versions of this and inffast.S can be found at

+ * http://www.eetbeetee.com/zlib/ and http://www.charm.net/~christop/zlib/

+ *

+ */

+

+#include <stdio.h>

+#include "zutil.h"

+#include "inftrees.h"

+#include "inflate.h"

+#include "inffast.h"

+

+/* Mark Adler's comments from inffast.c: */

+

+/*

+   Decode literal, length, and distance codes and write out the resulting

+   literal and match bytes until either not enough input or output is

+   available, an end-of-block is encountered, or a data error is encountered.

+   When large enough input and output buffers are supplied to inflate(), for

+   example, a 16K input buffer and a 64K output buffer, more than 95% of the

+   inflate execution time is spent in this routine.

+

+   Entry assumptions:

+

+        state->mode == LEN

+        strm->avail_in >= 6

+        strm->avail_out >= 258

+        start >= strm->avail_out

+        state->bits < 8

+

+   On return, state->mode is one of:

+

+        LEN -- ran out of enough output space or enough available input

+        TYPE -- reached end of block code, inflate() to interpret next block

+        BAD -- error in block data

+

+   Notes:

+

+    - The maximum input bits used by a length/distance pair is 15 bits for the

+      length code, 5 bits for the length extra, 15 bits for the distance code,

+      and 13 bits for the distance extra.  This totals 48 bits, or six bytes.

+      Therefore if strm->avail_in >= 6, then there is enough input to avoid

+      checking for available input while decoding.

+

+    - The maximum bytes that a single length/distance pair can output is 258

+      bytes, which is the maximum length that can be coded.  inflate_fast()

+      requires strm->avail_out >= 258 for each loop to avoid checking for

+      output space.

+ */

+

+

+

+    typedef struct inffast_ar {

+/* 64   32                               x86  x86_64 */

+/* ar offset                              register */

+/*  0    0 */ void *esp;                /* esp save */

+/*  8    4 */ void *ebp;                /* ebp save */

+/* 16    8 */ unsigned char FAR *in;    /* esi rsi  local strm->next_in */

+/* 24   12 */ unsigned char FAR *last;  /*     r9   while in < last */

+/* 32   16 */ unsigned char FAR *out;   /* edi rdi  local strm->next_out */

+/* 40   20 */ unsigned char FAR *beg;   /*          inflate()'s init next_out */

+/* 48   24 */ unsigned char FAR *end;   /*     r10  while out < end */

+/* 56   28 */ unsigned char FAR *window;/*          size of window, wsize!=0 */

+/* 64   32 */ code const FAR *lcode;    /* ebp rbp  local strm->lencode */

+/* 72   36 */ code const FAR *dcode;    /*     r11  local strm->distcode */

+/* 80   40 */ size_t /*unsigned long */hold;       /* edx rdx  local strm->hold */

+/* 88   44 */ unsigned bits;            /* ebx rbx  local strm->bits */

+/* 92   48 */ unsigned wsize;           /*          window size */

+/* 96   52 */ unsigned write;           /*          window write index */

+/*100   56 */ unsigned lmask;           /*     r12  mask for lcode */

+/*104   60 */ unsigned dmask;           /*     r13  mask for dcode */

+/*108   64 */ unsigned len;             /*     r14  match length */

+/*112   68 */ unsigned dist;            /*     r15  match distance */

+/*116   72 */ unsigned status;          /*          set when state chng*/

+    } type_ar;

+#ifdef ASMINF

+

+void inflate_fast(strm, start)

+z_streamp strm;

+unsigned start;         /* inflate()'s starting value for strm->avail_out */

+{

+    struct inflate_state FAR *state;

+    type_ar ar;

+    void inffas8664fnc(struct inffast_ar * par);

+

+    

+

+#if (defined( __GNUC__ ) && defined( __amd64__ ) && ! defined( __i386 )) || (defined(_MSC_VER) && defined(_M_AMD64))

+#define PAD_AVAIL_IN 6

+#define PAD_AVAIL_OUT 258    

+#else

+#define PAD_AVAIL_IN 5

+#define PAD_AVAIL_OUT 257

+#endif

+

+    /* copy state to local variables */

+    state = (struct inflate_state FAR *)strm->state;

+

+    ar.in = strm->next_in;

+    ar.last = ar.in + (strm->avail_in - PAD_AVAIL_IN);

+    ar.out = strm->next_out;

+    ar.beg = ar.out - (start - strm->avail_out);

+    ar.end = ar.out + (strm->avail_out - PAD_AVAIL_OUT);

+    ar.wsize = state->wsize;

+    ar.write = state->write;

+    ar.window = state->window;

+    ar.hold = state->hold;

+    ar.bits = state->bits;

+    ar.lcode = state->lencode;

+    ar.dcode = state->distcode;

+    ar.lmask = (1U << state->lenbits) - 1;

+    ar.dmask = (1U << state->distbits) - 1;

+

+    /* decode literals and length/distances until end-of-block or not enough

+       input data or output space */

+

+    /* align in on 1/2 hold size boundary */

+    while (((size_t)(void *)ar.in & (sizeof(ar.hold) / 2 - 1)) != 0) {

+        ar.hold += (unsigned long)*ar.in++ << ar.bits;

+        ar.bits += 8;

+    }

+

+    inffas8664fnc(&ar);

+

+    if (ar.status > 1) {

+        if (ar.status == 2)

+            strm->msg = "invalid literal/length code";

+        else if (ar.status == 3)

+            strm->msg = "invalid distance code";

+        else

+            strm->msg = "invalid distance too far back";

+        state->mode = BAD;

+    }

+    else if ( ar.status == 1 ) {

+        state->mode = TYPE;

+    }

+

+    /* return unused bytes (on entry, bits < 8, so in won't go too far back) */

+    ar.len = ar.bits >> 3;

+    ar.in -= ar.len;

+    ar.bits -= ar.len << 3;

+    ar.hold &= (1U << ar.bits) - 1;

+

+    /* update state and return */

+    strm->next_in = ar.in;

+    strm->next_out = ar.out;

+    strm->avail_in = (unsigned)(ar.in < ar.last ?

+                                PAD_AVAIL_IN + (ar.last - ar.in) :

+                                PAD_AVAIL_IN - (ar.in - ar.last));

+    strm->avail_out = (unsigned)(ar.out < ar.end ?

+                                 PAD_AVAIL_OUT + (ar.end - ar.out) :

+                                 PAD_AVAIL_OUT - (ar.out - ar.end));

+    state->hold = (unsigned long)ar.hold;

+    state->bits = ar.bits;

+    return;

+}

+

+#endif

diff --git a/gs/zlib/contrib/masmx64/inffasx64.asm b/gs/zlib/contrib/masmx64/inffasx64.asm
new file mode 100644
index 000000000..b5d93a272
--- /dev/null
+++ b/gs/zlib/contrib/masmx64/inffasx64.asm
@@ -0,0 +1,392 @@
+; inffasx64.asm is a hand tuned assembler version of inffast.c - fast decoding

+; version for AMD64 on Windows using Microsoft C compiler

+;

+; inffasx64.asm is automatically convert from AMD64 portion of inffas86.c

+; inffasx64.asm is called by inffas8664.c, which contain more info.

+

+

+; to compile this file, I use option

+;   ml64.exe /Flinffasx64 /c /Zi inffasx64.asm

+;   with Microsoft Macro Assembler (x64) for AMD64

+;

+;   ml64.exe is given with Visual Studio 2005, Windows 2003 server DDK

+;

+;   (you can get Windows 2003 server DDK with ml64 and cl.exe for AMD64 from 

+;      http://www.microsoft.com/whdc/devtools/ddk/default.mspx for low price)

+;

+

+.code

+inffas8664fnc PROC

+

+; see http://weblogs.asp.net/oldnewthing/archive/2004/01/14/58579.aspx and

+; http://msdn.microsoft.com/library/en-us/kmarch/hh/kmarch/64bitAMD_8e951dd2-ee77-4728-8702-55ce4b5dd24a.xml.asp

+;

+; All registers must be preserved across the call, except for

+;   rax, rcx, rdx, r8, r-9, r10, and r11, which are scratch.

+

+

+	mov [rsp-8],rsi

+	mov [rsp-16],rdi

+	mov [rsp-24],r12

+	mov [rsp-32],r13

+	mov [rsp-40],r14

+	mov [rsp-48],r15

+	mov [rsp-56],rbx

+

+	mov rax,rcx

+

+	mov	[rax+8], rbp       ; /* save regs rbp and rsp */

+	mov	[rax], rsp

+

+	mov	rsp, rax          ; /* make rsp point to &ar */

+

+	mov	rsi, [rsp+16]      ; /* rsi  = in */

+	mov	rdi, [rsp+32]      ; /* rdi  = out */

+	mov	r9, [rsp+24]       ; /* r9   = last */

+	mov	r10, [rsp+48]      ; /* r10  = end */

+	mov	rbp, [rsp+64]      ; /* rbp  = lcode */

+	mov	r11, [rsp+72]      ; /* r11  = dcode */

+	mov	rdx, [rsp+80]      ; /* rdx  = hold */

+	mov	ebx, [rsp+88]      ; /* ebx  = bits */

+	mov	r12d, [rsp+100]    ; /* r12d = lmask */

+	mov	r13d, [rsp+104]    ; /* r13d = dmask */

+                                          ; /* r14d = len */

+                                          ; /* r15d = dist */

+

+

+	cld

+	cmp	r10, rdi

+	je	L_one_time           ; /* if only one decode left */

+	cmp	r9, rsi

+

+    jne L_do_loop

+

+

+L_one_time:

+	mov	r8, r12           ; /* r8 = lmask */

+	cmp	bl, 32

+	ja	L_get_length_code_one_time

+

+	lodsd                         ; /* eax = *(uint *)in++ */

+	mov	cl, bl            ; /* cl = bits, needs it for shifting */

+	add	bl, 32             ; /* bits += 32 */

+	shl	rax, cl

+	or	rdx, rax          ; /* hold |= *((uint *)in)++ << bits */

+	jmp	L_get_length_code_one_time

+

+ALIGN 4

+L_while_test:

+	cmp	r10, rdi

+	jbe	L_break_loop

+	cmp	r9, rsi

+	jbe	L_break_loop

+

+L_do_loop:

+	mov	r8, r12           ; /* r8 = lmask */

+	cmp	bl, 32

+	ja	L_get_length_code    ; /* if (32 < bits) */

+

+	lodsd                         ; /* eax = *(uint *)in++ */

+	mov	cl, bl            ; /* cl = bits, needs it for shifting */

+	add	bl, 32             ; /* bits += 32 */

+	shl	rax, cl

+	or	rdx, rax          ; /* hold |= *((uint *)in)++ << bits */

+

+L_get_length_code:

+	and	r8, rdx            ; /* r8 &= hold */

+	mov	eax, [rbp+r8*4]  ; /* eax = lcode[hold & lmask] */

+

+	mov	cl, ah            ; /* cl = this.bits */

+	sub	bl, ah            ; /* bits -= this.bits */

+	shr	rdx, cl           ; /* hold >>= this.bits */

+

+	test	al, al

+	jnz	L_test_for_length_base ; /* if (op != 0) 45.7% */

+

+	mov	r8, r12            ; /* r8 = lmask */

+	shr	eax, 16            ; /* output this.val char */

+	stosb

+

+L_get_length_code_one_time:

+	and	r8, rdx            ; /* r8 &= hold */

+	mov	eax, [rbp+r8*4] ; /* eax = lcode[hold & lmask] */

+

+L_dolen:

+	mov	cl, ah            ; /* cl = this.bits */

+	sub	bl, ah            ; /* bits -= this.bits */

+	shr	rdx, cl           ; /* hold >>= this.bits */

+

+	test	al, al

+	jnz	L_test_for_length_base ; /* if (op != 0) 45.7% */

+

+	shr	eax, 16            ; /* output this.val char */

+	stosb

+	jmp	L_while_test

+

+ALIGN 4

+L_test_for_length_base:

+	mov	r14d, eax         ; /* len = this */

+	shr	r14d, 16           ; /* len = this.val */

+	mov	cl, al

+

+	test	al, 16

+	jz	L_test_for_second_level_length ; /* if ((op & 16) == 0) 8% */

+	and	cl, 15             ; /* op &= 15 */

+	jz	L_decode_distance    ; /* if (!op) */

+

+L_add_bits_to_len:

+	sub	bl, cl

+	xor	eax, eax

+	inc	eax

+	shl	eax, cl

+	dec	eax

+	and	eax, edx          ; /* eax &= hold */

+	shr	rdx, cl

+	add	r14d, eax         ; /* len += hold & mask[op] */

+

+L_decode_distance:

+	mov	r8, r13           ; /* r8 = dmask */

+	cmp	bl, 32

+	ja	L_get_distance_code  ; /* if (32 < bits) */

+

+	lodsd                         ; /* eax = *(uint *)in++ */

+	mov	cl, bl            ; /* cl = bits, needs it for shifting */

+	add	bl, 32             ; /* bits += 32 */

+	shl	rax, cl

+	or	rdx, rax          ; /* hold |= *((uint *)in)++ << bits */

+

+L_get_distance_code:

+	and	r8, rdx           ; /* r8 &= hold */

+	mov	eax, [r11+r8*4] ; /* eax = dcode[hold & dmask] */

+

+L_dodist:

+	mov	r15d, eax         ; /* dist = this */

+	shr	r15d, 16           ; /* dist = this.val */

+	mov	cl, ah

+	sub	bl, ah            ; /* bits -= this.bits */

+	shr	rdx, cl           ; /* hold >>= this.bits */

+	mov	cl, al            ; /* cl = this.op */

+

+	test	al, 16             ; /* if ((op & 16) == 0) */

+	jz	L_test_for_second_level_dist

+	and	cl, 15             ; /* op &= 15 */

+	jz	L_check_dist_one

+

+L_add_bits_to_dist:

+	sub	bl, cl

+	xor	eax, eax

+	inc	eax

+	shl	eax, cl

+	dec	eax                 ; /* (1 << op) - 1 */

+	and	eax, edx          ; /* eax &= hold */

+	shr	rdx, cl

+	add	r15d, eax         ; /* dist += hold & ((1 << op) - 1) */

+

+L_check_window:

+	mov	r8, rsi           ; /* save in so from can use it's reg */

+	mov	rax, rdi

+	sub	rax, [rsp+40]      ; /* nbytes = out - beg */

+

+	cmp	eax, r15d

+	jb	L_clip_window        ; /* if (dist > nbytes) 4.2% */

+

+	mov	ecx, r14d         ; /* ecx = len */

+	mov	rsi, rdi

+	sub	rsi, r15          ; /* from = out - dist */

+

+	sar	ecx, 1

+	jnc	L_copy_two           ; /* if len % 2 == 0 */

+

+	rep     movsw

+	mov	al, [rsi]

+	mov	[rdi], al

+	inc	rdi

+

+	mov	rsi, r8           ; /* move in back to %rsi, toss from */

+	jmp	L_while_test

+

+L_copy_two:

+	rep     movsw

+	mov	rsi, r8           ; /* move in back to %rsi, toss from */

+	jmp	L_while_test

+

+ALIGN 4

+L_check_dist_one:

+	cmp	r15d, 1            ; /* if dist 1, is a memset */

+	jne	L_check_window

+	cmp	[rsp+40], rdi      ; /* if out == beg, outside window */

+	je	L_check_window

+

+	mov	ecx, r14d         ; /* ecx = len */

+	mov	al, [rdi-1]

+	mov	ah, al

+

+	sar	ecx, 1

+	jnc	L_set_two

+	mov	[rdi], al

+	inc	rdi

+

+L_set_two:

+	rep     stosw

+	jmp	L_while_test

+

+ALIGN 4

+L_test_for_second_level_length:

+	test	al, 64

+	jnz	L_test_for_end_of_block ; /* if ((op & 64) != 0) */

+

+	xor	eax, eax

+	inc	eax

+	shl	eax, cl

+	dec	eax

+	and	eax, edx         ; /* eax &= hold */

+	add	eax, r14d        ; /* eax += len */

+	mov	eax, [rbp+rax*4] ; /* eax = lcode[val+(hold&mask[op])]*/

+	jmp	L_dolen

+

+ALIGN 4

+L_test_for_second_level_dist:

+	test	al, 64

+	jnz	L_invalid_distance_code ; /* if ((op & 64) != 0) */

+

+	xor	eax, eax

+	inc	eax

+	shl	eax, cl

+	dec	eax

+	and	eax, edx         ; /* eax &= hold */

+	add	eax, r15d        ; /* eax += dist */

+	mov	eax, [r11+rax*4] ; /* eax = dcode[val+(hold&mask[op])]*/

+	jmp	L_dodist

+

+ALIGN 4

+L_clip_window:

+	mov	ecx, eax         ; /* ecx = nbytes */

+	mov	eax, [rsp+92]     ; /* eax = wsize, prepare for dist cmp */

+	neg	ecx                ; /* nbytes = -nbytes */

+

+	cmp	eax, r15d

+	jb	L_invalid_distance_too_far ; /* if (dist > wsize) */

+

+	add	ecx, r15d         ; /* nbytes = dist - nbytes */

+	cmp	dword ptr [rsp+96], 0

+	jne	L_wrap_around_window ; /* if (write != 0) */

+

+	mov	rsi, [rsp+56]     ; /* from  = window */

+	sub	eax, ecx         ; /* eax  -= nbytes */

+	add	rsi, rax         ; /* from += wsize - nbytes */

+

+	mov	eax, r14d        ; /* eax = len */

+	cmp	r14d, ecx

+	jbe	L_do_copy           ; /* if (nbytes >= len) */

+

+	sub	eax, ecx         ; /* eax -= nbytes */

+	rep     movsb

+	mov	rsi, rdi

+	sub	rsi, r15         ; /* from = &out[ -dist ] */

+	jmp	L_do_copy

+

+ALIGN 4

+L_wrap_around_window:

+	mov	eax, [rsp+96]     ; /* eax = write */

+	cmp	ecx, eax

+	jbe	L_contiguous_in_window ; /* if (write >= nbytes) */

+

+	mov	esi, [rsp+92]     ; /* from  = wsize */

+	add	rsi, [rsp+56]     ; /* from += window */

+	add	rsi, rax         ; /* from += write */

+	sub	rsi, rcx         ; /* from -= nbytes */

+	sub	ecx, eax         ; /* nbytes -= write */

+

+	mov	eax, r14d        ; /* eax = len */

+	cmp	eax, ecx

+	jbe	L_do_copy           ; /* if (nbytes >= len) */

+

+	sub	eax, ecx         ; /* len -= nbytes */

+	rep     movsb

+	mov	rsi, [rsp+56]     ; /* from = window */

+	mov	ecx, [rsp+96]     ; /* nbytes = write */

+	cmp	eax, ecx

+	jbe	L_do_copy           ; /* if (nbytes >= len) */

+

+	sub	eax, ecx         ; /* len -= nbytes */

+	rep     movsb

+	mov	rsi, rdi

+	sub	rsi, r15         ; /* from = out - dist */

+	jmp	L_do_copy

+

+ALIGN 4

+L_contiguous_in_window:

+	mov	rsi, [rsp+56]     ; /* rsi = window */

+	add	rsi, rax

+	sub	rsi, rcx         ; /* from += write - nbytes */

+

+	mov	eax, r14d        ; /* eax = len */

+	cmp	eax, ecx

+	jbe	L_do_copy           ; /* if (nbytes >= len) */

+

+	sub	eax, ecx         ; /* len -= nbytes */

+	rep     movsb

+	mov	rsi, rdi

+	sub	rsi, r15         ; /* from = out - dist */

+	jmp	L_do_copy           ; /* if (nbytes >= len) */

+

+ALIGN 4

+L_do_copy:

+	mov	ecx, eax         ; /* ecx = len */

+	rep     movsb

+

+	mov	rsi, r8          ; /* move in back to %esi, toss from */

+	jmp	L_while_test

+

+L_test_for_end_of_block:

+	test	al, 32

+	jz	L_invalid_literal_length_code

+	mov	dword ptr [rsp+116], 1

+	jmp	L_break_loop_with_status

+

+L_invalid_literal_length_code:

+	mov	dword ptr [rsp+116], 2

+	jmp	L_break_loop_with_status

+

+L_invalid_distance_code:

+	mov	dword ptr [rsp+116], 3

+	jmp	L_break_loop_with_status

+

+L_invalid_distance_too_far:

+	mov	dword ptr [rsp+116], 4

+	jmp	L_break_loop_with_status

+

+L_break_loop:

+	mov	dword ptr [rsp+116], 0

+

+L_break_loop_with_status:

+; /* put in, out, bits, and hold back into ar and pop esp */

+	mov	[rsp+16], rsi     ; /* in */

+	mov	[rsp+32], rdi     ; /* out */

+	mov	[rsp+88], ebx     ; /* bits */

+	mov	[rsp+80], rdx     ; /* hold */

+

+	mov	rax, [rsp]       ; /* restore rbp and rsp */

+	mov	rbp, [rsp+8]

+	mov	rsp, rax

+

+

+

+	mov rsi,[rsp-8]

+	mov rdi,[rsp-16]

+	mov r12,[rsp-24]

+	mov r13,[rsp-32]

+	mov r14,[rsp-40]

+	mov r15,[rsp-48]

+	mov rbx,[rsp-56]

+	

+    ret 0

+;          :

+;          : "m" (ar)

+;          : "memory", "%rax", "%rbx", "%rcx", "%rdx", "%rsi", "%rdi",

+;            "%r8", "%r9", "%r10", "%r11", "%r12", "%r13", "%r14", "%r15"

+;    );

+

+inffas8664fnc 	ENDP

+;_TEXT	ENDS

+END

diff --git a/gs/zlib/contrib/masmx64/inffasx64.obj b/gs/zlib/contrib/masmx64/inffasx64.obj
new file mode 100644
index 000000000..8df5d8261
--- /dev/null
+++ b/gs/zlib/contrib/masmx64/inffasx64.obj
diff --git a/gs/zlib/contrib/masmx64/readme.txt b/gs/zlib/contrib/masmx64/readme.txt
new file mode 100644
index 000000000..ee03115c5
--- /dev/null
+++ b/gs/zlib/contrib/masmx64/readme.txt
@@ -0,0 +1,28 @@
+Summary

+-------

+This directory contains ASM implementations of the functions

+longest_match() and inflate_fast(), for 64 bits x86 (both AMD64 and Intel EM64t),

+for use with Microsoft Macro Assembler (x64) for AMD64 and Microsoft C++ 64 bits.

+

+gvmat64.asm is written by Gilles Vollant (2005), by using Brian Raiter 686/32 bits

+   assembly optimized version from Jean-loup Gailly original longest_match function

+

+inffasx64.asm and inffas8664.c were written by Chris Anderson, by optimizing

+   original function from Mark Adler

+

+Use instructions

+----------------

+Copy these files into the zlib source directory.

+

+define ASMV and ASMINF in your project. Include inffas8664.c in your source tree,

+and inffasx64.obj and gvmat64.obj as object to link.

+

+

+Build instructions

+------------------

+run bld_64.bat with Microsoft Macro Assembler (x64) for AMD64 (ml64.exe)

+

+ml64.exe is given with Visual Studio 2005, Windows 2003 server DDK

+

+You can get Windows 2003 server DDK with ml64 and cl for AMD64 from 

+  http://www.microsoft.com/whdc/devtools/ddk/default.mspx for low price)

diff --git a/gs/zlib/contrib/masmx86/bld_ml32.bat b/gs/zlib/contrib/masmx86/bld_ml32.bat
new file mode 100644
index 000000000..99144d07a
--- /dev/null
+++ b/gs/zlib/contrib/masmx86/bld_ml32.bat
@@ -0,0 +1,2 @@
+ml /coff /Zi /c /Flgvmat32.lst  gvmat32.asm 

+ml /coff /Zi /c /Flinffas32.lst inffas32.asm 

diff --git a/gs/zlib/contrib/masmx86/gvmat32.asm b/gs/zlib/contrib/masmx86/gvmat32.asm
new file mode 100644
index 000000000..874bb2d48
--- /dev/null
+++ b/gs/zlib/contrib/masmx86/gvmat32.asm
@@ -0,0 +1,972 @@
+; gvmat32.asm -- Asm portion of the optimized longest_match for 32 bits x86

+; Copyright (C) 1995-1996 Jean-loup Gailly and Gilles Vollant.

+; File written by Gilles Vollant, by modifiying the longest_match

+;  from Jean-loup Gailly in deflate.c

+;

+;         http://www.zlib.net

+;         http://www.winimage.com/zLibDll

+;         http://www.muppetlabs.com/~breadbox/software/assembly.html

+;

+; For Visual C++ 4.x and higher and ML 6.x and higher

+;   ml.exe is in directory \MASM611C of Win95 DDK

+;   ml.exe is also distributed in http://www.masm32.com/masmdl.htm

+;    and in VC++2003 toolkit at http://msdn.microsoft.com/visualc/vctoolkit2003/

+;

+; this file contain two implementation of longest_match

+;

+;  longest_match_7fff : written 1996 by Gilles Vollant optimized for 

+;            first Pentium. Assume s->w_mask == 0x7fff

+;  longest_match_686 : written by Brian raiter (1998), optimized for Pentium Pro

+;

+;  for using an seembly version of longest_match, you need define ASMV in project

+;  There is two way in using gvmat32.asm

+;

+;  A) Suggested method

+;    if you want include both longest_match_7fff and longest_match_686

+;    compile the asm file running

+;           ml /coff /Zi /Flgvmat32.lst /c gvmat32.asm

+;    and include gvmat32c.c in your project

+;    if you have an old cpu (386,486 or first Pentium) and s->w_mask==0x7fff,

+;        longest_match_7fff will be used

+;    if you have a more modern CPU (Pentium Pro, II and higher)

+;        longest_match_686 will be used

+;    on old cpu with s->w_mask!=0x7fff, longest_match_686 will be used,

+;        but this is not a sitation you'll find often

+;

+;  B) Alternative

+;    if you are not interresed in old cpu performance and want the smaller

+;       binaries possible

+;

+;    compile the asm file running

+;           ml /coff /Zi /c /Flgvmat32.lst /DNOOLDPENTIUMCODE gvmat32.asm

+;    and do not include gvmat32c.c in your project (ou define also 

+;              NOOLDPENTIUMCODE)

+;

+; note : as I known, longest_match_686 is very faster than longest_match_7fff

+;        on pentium Pro/II/III, faster (but less) in P4, but it seem

+;        longest_match_7fff can be faster (very very litte) on AMD Athlon64/K8

+;

+; see below : zlib1222add must be adjuster if you use a zlib version < 1.2.2.2

+

+;uInt longest_match_7fff(s, cur_match)

+;    deflate_state *s;

+;    IPos cur_match;                             /* current match */

+

+    NbStack         equ     76

+    cur_match       equ     dword ptr[esp+NbStack-0]

+    str_s           equ     dword ptr[esp+NbStack-4]

+; 5 dword on top (ret,ebp,esi,edi,ebx)

+    adrret          equ     dword ptr[esp+NbStack-8]

+    pushebp         equ     dword ptr[esp+NbStack-12]

+    pushedi         equ     dword ptr[esp+NbStack-16]

+    pushesi         equ     dword ptr[esp+NbStack-20]

+    pushebx         equ     dword ptr[esp+NbStack-24]

+

+    chain_length    equ     dword ptr [esp+NbStack-28]

+    limit           equ     dword ptr [esp+NbStack-32]

+    best_len        equ     dword ptr [esp+NbStack-36]

+    window          equ     dword ptr [esp+NbStack-40]

+    prev            equ     dword ptr [esp+NbStack-44]

+    scan_start      equ      word ptr [esp+NbStack-48]

+    wmask           equ     dword ptr [esp+NbStack-52]

+    match_start_ptr equ     dword ptr [esp+NbStack-56]

+    nice_match      equ     dword ptr [esp+NbStack-60]

+    scan            equ     dword ptr [esp+NbStack-64]

+

+    windowlen       equ     dword ptr [esp+NbStack-68]

+    match_start     equ     dword ptr [esp+NbStack-72]

+    strend          equ     dword ptr [esp+NbStack-76]

+    NbStackAdd      equ     (NbStack-24)

+

+    .386p

+

+    name    gvmatch

+    .MODEL  FLAT

+

+

+

+;  all the +zlib1222add offsets are due to the addition of fields

+;  in zlib in the deflate_state structure since the asm code was first written

+;  (if you compile with zlib 1.0.4 or older, use "zlib1222add equ (-4)").

+;  (if you compile with zlib between 1.0.5 and 1.2.2.1, use "zlib1222add equ 0").

+;  if you compile with zlib 1.2.2.2 or later , use "zlib1222add equ 8").

+

+    zlib1222add         equ     8

+

+;  Note : these value are good with a 8 bytes boundary pack structure

+    dep_chain_length    equ     74h+zlib1222add

+    dep_window          equ     30h+zlib1222add

+    dep_strstart        equ     64h+zlib1222add

+    dep_prev_length     equ     70h+zlib1222add

+    dep_nice_match      equ     88h+zlib1222add

+    dep_w_size          equ     24h+zlib1222add

+    dep_prev            equ     38h+zlib1222add

+    dep_w_mask          equ     2ch+zlib1222add

+    dep_good_match      equ     84h+zlib1222add

+    dep_match_start     equ     68h+zlib1222add

+    dep_lookahead       equ     6ch+zlib1222add

+

+

+_TEXT                   segment

+

+IFDEF NOUNDERLINE

+   IFDEF NOOLDPENTIUMCODE

+            public  longest_match

+            public  match_init

+   ELSE            

+            public  longest_match_7fff

+            public  cpudetect32

+            public  longest_match_686

+   ENDIF

+ELSE

+   IFDEF NOOLDPENTIUMCODE

+            public  _longest_match

+            public  _match_init

+   ELSE

+            public  _longest_match_7fff

+            public  _cpudetect32

+            public  _longest_match_686

+   ENDIF

+ENDIF

+

+    MAX_MATCH           equ     258

+    MIN_MATCH           equ     3

+    MIN_LOOKAHEAD       equ     (MAX_MATCH+MIN_MATCH+1)

+

+

+

+IFNDEF NOOLDPENTIUMCODE

+IFDEF NOUNDERLINE

+longest_match_7fff   proc near

+ELSE

+_longest_match_7fff  proc near

+ENDIF

+

+    mov     edx,[esp+4]

+

+

+

+    push    ebp

+    push    edi

+    push    esi

+    push    ebx

+

+    sub     esp,NbStackAdd

+

+; initialize or check the variables used in match.asm.

+    mov     ebp,edx

+

+; chain_length = s->max_chain_length

+; if (prev_length>=good_match) chain_length >>= 2

+    mov     edx,[ebp+dep_chain_length]

+    mov     ebx,[ebp+dep_prev_length]

+    cmp     [ebp+dep_good_match],ebx

+    ja      noshr

+    shr     edx,2

+noshr:

+; we increment chain_length because in the asm, the --chain_lenght is in the beginning of the loop

+    inc     edx

+    mov     edi,[ebp+dep_nice_match]

+    mov     chain_length,edx

+    mov     eax,[ebp+dep_lookahead]

+    cmp     eax,edi

+; if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;

+    jae     nolookaheadnicematch

+    mov     edi,eax

+nolookaheadnicematch:

+; best_len = s->prev_length

+    mov     best_len,ebx

+

+; window = s->window

+    mov     esi,[ebp+dep_window]

+    mov     ecx,[ebp+dep_strstart]

+    mov     window,esi

+

+    mov     nice_match,edi

+; scan = window + strstart

+    add     esi,ecx

+    mov     scan,esi

+; dx = *window

+    mov     dx,word ptr [esi]

+; bx = *(window+best_len-1)

+    mov     bx,word ptr [esi+ebx-1]

+    add     esi,MAX_MATCH-1

+; scan_start = *scan

+    mov     scan_start,dx

+; strend = scan + MAX_MATCH-1

+    mov     strend,esi

+; bx = scan_end = *(window+best_len-1)

+

+;    IPos limit = s->strstart > (IPos)MAX_DIST(s) ?

+;        s->strstart - (IPos)MAX_DIST(s) : NIL;

+

+    mov     esi,[ebp+dep_w_size]

+    sub     esi,MIN_LOOKAHEAD

+; here esi = MAX_DIST(s)

+    sub     ecx,esi

+    ja      nodist

+    xor     ecx,ecx

+nodist:

+    mov     limit,ecx

+

+; prev = s->prev

+    mov     edx,[ebp+dep_prev]

+    mov     prev,edx

+

+;

+    mov     edx,dword ptr [ebp+dep_match_start]

+    mov     bp,scan_start

+    mov     eax,cur_match

+    mov     match_start,edx

+

+    mov     edx,window

+    mov     edi,edx

+    add     edi,best_len

+    mov     esi,prev

+    dec     edi

+; windowlen = window + best_len -1

+    mov     windowlen,edi

+

+    jmp     beginloop2

+    align   4

+

+; here, in the loop

+;       eax = ax = cur_match

+;       ecx = limit

+;        bx = scan_end

+;        bp = scan_start

+;       edi = windowlen (window + best_len -1)

+;       esi = prev

+

+

+;// here; chain_length <=16

+normalbeg0add16:

+    add     chain_length,16

+    jz      exitloop

+normalbeg0:

+    cmp     word ptr[edi+eax],bx

+    je      normalbeg2noroll

+rcontlabnoroll:

+; cur_match = prev[cur_match & wmask]

+    and     eax,7fffh

+    mov     ax,word ptr[esi+eax*2]

+; if cur_match > limit, go to exitloop

+    cmp     ecx,eax

+    jnb     exitloop

+; if --chain_length != 0, go to exitloop

+    dec     chain_length

+    jnz     normalbeg0

+    jmp     exitloop

+

+normalbeg2noroll:

+; if (scan_start==*(cur_match+window)) goto normalbeg2

+    cmp     bp,word ptr[edx+eax]

+    jne     rcontlabnoroll

+    jmp     normalbeg2

+

+contloop3:

+    mov     edi,windowlen

+

+; cur_match = prev[cur_match & wmask]

+    and     eax,7fffh

+    mov     ax,word ptr[esi+eax*2]

+; if cur_match > limit, go to exitloop

+    cmp     ecx,eax

+jnbexitloopshort1:

+    jnb     exitloop

+; if --chain_length != 0, go to exitloop

+

+

+; begin the main loop

+beginloop2:

+    sub     chain_length,16+1

+; if chain_length <=16, don't use the unrolled loop

+    jna     normalbeg0add16

+

+do16:

+    cmp     word ptr[edi+eax],bx

+    je      normalbeg2dc0

+

+maccn   MACRO   lab

+    and     eax,7fffh

+    mov     ax,word ptr[esi+eax*2]

+    cmp     ecx,eax

+    jnb     exitloop

+    cmp     word ptr[edi+eax],bx

+    je      lab

+    ENDM

+

+rcontloop0:

+    maccn   normalbeg2dc1

+

+rcontloop1:

+    maccn   normalbeg2dc2

+

+rcontloop2:

+    maccn   normalbeg2dc3

+

+rcontloop3:

+    maccn   normalbeg2dc4

+

+rcontloop4:

+    maccn   normalbeg2dc5

+

+rcontloop5:

+    maccn   normalbeg2dc6

+

+rcontloop6:

+    maccn   normalbeg2dc7

+

+rcontloop7:

+    maccn   normalbeg2dc8

+

+rcontloop8:

+    maccn   normalbeg2dc9

+

+rcontloop9:

+    maccn   normalbeg2dc10

+

+rcontloop10:

+    maccn   short normalbeg2dc11

+

+rcontloop11:

+    maccn   short normalbeg2dc12

+

+rcontloop12:

+    maccn   short normalbeg2dc13

+

+rcontloop13:

+    maccn   short normalbeg2dc14

+

+rcontloop14:

+    maccn   short normalbeg2dc15

+

+rcontloop15:

+    and     eax,7fffh

+    mov     ax,word ptr[esi+eax*2]

+    cmp     ecx,eax

+    jnb     exitloop

+

+    sub     chain_length,16

+    ja      do16

+    jmp     normalbeg0add16

+

+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

+

+normbeg MACRO   rcontlab,valsub

+; if we are here, we know that *(match+best_len-1) == scan_end

+    cmp     bp,word ptr[edx+eax]

+; if (match != scan_start) goto rcontlab

+    jne     rcontlab

+; calculate the good chain_length, and we'll compare scan and match string

+    add     chain_length,16-valsub

+    jmp     iseq

+    ENDM

+

+

+normalbeg2dc11:

+    normbeg rcontloop11,11

+

+normalbeg2dc12:

+    normbeg short rcontloop12,12

+

+normalbeg2dc13:

+    normbeg short rcontloop13,13

+

+normalbeg2dc14:

+    normbeg short rcontloop14,14

+

+normalbeg2dc15:

+    normbeg short rcontloop15,15

+

+normalbeg2dc10:

+    normbeg rcontloop10,10

+

+normalbeg2dc9:

+    normbeg rcontloop9,9

+

+normalbeg2dc8:

+    normbeg rcontloop8,8

+

+normalbeg2dc7:

+    normbeg rcontloop7,7

+

+normalbeg2dc6:

+    normbeg rcontloop6,6

+

+normalbeg2dc5:

+    normbeg rcontloop5,5

+

+normalbeg2dc4:

+    normbeg rcontloop4,4

+

+normalbeg2dc3:

+    normbeg rcontloop3,3

+

+normalbeg2dc2:

+    normbeg rcontloop2,2

+

+normalbeg2dc1:

+    normbeg rcontloop1,1

+

+normalbeg2dc0:

+    normbeg rcontloop0,0

+

+

+; we go in normalbeg2 because *(ushf*)(match+best_len-1) == scan_end

+

+normalbeg2:

+    mov     edi,window

+

+    cmp     bp,word ptr[edi+eax]

+    jne     contloop3                   ; if *(ushf*)match != scan_start, continue

+

+iseq:

+; if we are here, we know that *(match+best_len-1) == scan_end

+; and (match == scan_start)

+

+    mov     edi,edx

+    mov     esi,scan                    ; esi = scan

+    add     edi,eax                     ; edi = window + cur_match = match

+

+    mov     edx,[esi+3]                 ; compare manually dword at match+3

+    xor     edx,[edi+3]                 ; and scan +3

+

+    jz      begincompare                ; if equal, go to long compare

+

+; we will determine the unmatch byte and calculate len (in esi)

+    or      dl,dl

+    je      eq1rr

+    mov     esi,3

+    jmp     trfinval

+eq1rr:

+    or      dx,dx

+    je      eq1

+

+    mov     esi,4

+    jmp     trfinval

+eq1:

+    and     edx,0ffffffh

+    jz      eq11

+    mov     esi,5

+    jmp     trfinval

+eq11:

+    mov     esi,6

+    jmp     trfinval

+

+begincompare:

+    ; here we now scan and match begin same

+    add     edi,6

+    add     esi,6

+    mov     ecx,(MAX_MATCH-(2+4))/4     ; scan for at most MAX_MATCH bytes

+    repe    cmpsd                       ; loop until mismatch

+

+    je      trfin                       ; go to trfin if not unmatch

+; we determine the unmatch byte

+    sub     esi,4

+    mov     edx,[edi-4]

+    xor     edx,[esi]

+

+    or      dl,dl

+    jnz     trfin

+    inc     esi

+

+    or      dx,dx

+    jnz     trfin

+    inc     esi

+

+    and     edx,0ffffffh

+    jnz     trfin

+    inc     esi

+

+trfin:

+    sub     esi,scan          ; esi = len

+trfinval:

+; here we have finised compare, and esi contain len of equal string

+    cmp     esi,best_len        ; if len > best_len, go newbestlen

+    ja      short newbestlen

+; now we restore edx, ecx and esi, for the big loop

+    mov     esi,prev

+    mov     ecx,limit

+    mov     edx,window

+    jmp     contloop3

+

+newbestlen:

+    mov     best_len,esi        ; len become best_len

+

+    mov     match_start,eax     ; save new position as match_start

+    cmp     esi,nice_match      ; if best_len >= nice_match, exit

+    jae     exitloop

+    mov     ecx,scan

+    mov     edx,window          ; restore edx=window

+    add     ecx,esi

+    add     esi,edx

+

+    dec     esi

+    mov     windowlen,esi       ; windowlen = window + best_len-1

+    mov     bx,[ecx-1]          ; bx = *(scan+best_len-1) = scan_end

+

+; now we restore ecx and esi, for the big loop :

+    mov     esi,prev

+    mov     ecx,limit

+    jmp     contloop3

+

+exitloop:

+; exit : s->match_start=match_start

+    mov     ebx,match_start

+    mov     ebp,str_s

+    mov     ecx,best_len

+    mov     dword ptr [ebp+dep_match_start],ebx

+    mov     eax,dword ptr [ebp+dep_lookahead]

+    cmp     ecx,eax

+    ja      minexlo

+    mov     eax,ecx

+minexlo:

+; return min(best_len,s->lookahead)

+

+; restore stack and register ebx,esi,edi,ebp

+    add     esp,NbStackAdd

+

+    pop     ebx

+    pop     esi

+    pop     edi

+    pop     ebp

+    ret

+InfoAuthor:

+; please don't remove this string !

+; Your are free use gvmat32 in any fre or commercial apps if you don't remove the string in the binary!

+    db     0dh,0ah,"GVMat32 optimised assembly code written 1996-98 by Gilles Vollant",0dh,0ah

+

+

+

+IFDEF NOUNDERLINE

+longest_match_7fff   endp

+ELSE

+_longest_match_7fff  endp

+ENDIF

+

+

+IFDEF NOUNDERLINE

+cpudetect32     proc near

+ELSE

+_cpudetect32    proc near

+ENDIF

+

+    push    ebx

+

+    pushfd                  ; push original EFLAGS

+    pop     eax             ; get original EFLAGS

+    mov     ecx, eax        ; save original EFLAGS

+    xor     eax, 40000h     ; flip AC bit in EFLAGS

+    push    eax             ; save new EFLAGS value on stack

+    popfd                   ; replace current EFLAGS value

+    pushfd                  ; get new EFLAGS

+    pop     eax             ; store new EFLAGS in EAX

+    xor     eax, ecx        ; can’t toggle AC bit, processor=80386

+    jz      end_cpu_is_386  ; jump if 80386 processor

+    push    ecx

+    popfd                   ; restore AC bit in EFLAGS first

+

+    pushfd

+    pushfd

+    pop     ecx

+

+    mov     eax, ecx        ; get original EFLAGS

+    xor     eax, 200000h    ; flip ID bit in EFLAGS

+    push    eax             ; save new EFLAGS value on stack

+    popfd                   ; replace current EFLAGS value

+    pushfd                  ; get new EFLAGS

+    pop     eax             ; store new EFLAGS in EAX

+    popfd                   ; restore original EFLAGS

+    xor     eax, ecx        ; can’t toggle ID bit,

+    je      is_old_486      ; processor=old

+

+    mov     eax,1

+    db      0fh,0a2h        ;CPUID

+

+exitcpudetect:

+    pop ebx

+    ret

+

+end_cpu_is_386:

+    mov     eax,0300h

+    jmp     exitcpudetect

+

+is_old_486:

+    mov     eax,0400h

+    jmp     exitcpudetect

+

+IFDEF NOUNDERLINE

+cpudetect32     endp

+ELSE

+_cpudetect32    endp

+ENDIF

+ENDIF

+

+MAX_MATCH       equ     258

+MIN_MATCH       equ     3

+MIN_LOOKAHEAD   equ     (MAX_MATCH + MIN_MATCH + 1)

+MAX_MATCH_8_     equ     ((MAX_MATCH + 7) AND 0FFF0h)

+

+

+;;; stack frame offsets

+

+chainlenwmask   equ  esp + 0    ; high word: current chain len

+                    ; low word: s->wmask

+window      equ  esp + 4    ; local copy of s->window

+windowbestlen   equ  esp + 8    ; s->window + bestlen

+scanstart   equ  esp + 16   ; first two bytes of string

+scanend     equ  esp + 12   ; last two bytes of string

+scanalign   equ  esp + 20   ; dword-misalignment of string

+nicematch   equ  esp + 24   ; a good enough match size

+bestlen     equ  esp + 28   ; size of best match so far

+scan        equ  esp + 32   ; ptr to string wanting match

+

+LocalVarsSize   equ 36

+;   saved ebx   byte esp + 36

+;   saved edi   byte esp + 40

+;   saved esi   byte esp + 44

+;   saved ebp   byte esp + 48

+;   return address  byte esp + 52

+deflatestate    equ  esp + 56   ; the function arguments

+curmatch    equ  esp + 60

+

+;;; Offsets for fields in the deflate_state structure. These numbers

+;;; are calculated from the definition of deflate_state, with the

+;;; assumption that the compiler will dword-align the fields. (Thus,

+;;; changing the definition of deflate_state could easily cause this

+;;; program to crash horribly, without so much as a warning at

+;;; compile time. Sigh.)

+

+dsWSize     equ 36+zlib1222add

+dsWMask     equ 44+zlib1222add

+dsWindow    equ 48+zlib1222add

+dsPrev      equ 56+zlib1222add

+dsMatchLen  equ 88+zlib1222add

+dsPrevMatch equ 92+zlib1222add

+dsStrStart  equ 100+zlib1222add

+dsMatchStart    equ 104+zlib1222add

+dsLookahead equ 108+zlib1222add

+dsPrevLen   equ 112+zlib1222add

+dsMaxChainLen   equ 116+zlib1222add

+dsGoodMatch equ 132+zlib1222add

+dsNiceMatch equ 136+zlib1222add

+

+

+;;; match.asm -- Pentium-Pro-optimized version of longest_match()

+;;; Written for zlib 1.1.2

+;;; Copyright (C) 1998 Brian Raiter <breadbox@muppetlabs.com>

+;;; You can look at http://www.muppetlabs.com/~breadbox/software/assembly.html

+;;;

+;;; This is free software; you can redistribute it and/or modify it

+;;; under the terms of the GNU General Public License.

+

+;GLOBAL _longest_match, _match_init

+

+

+;SECTION    .text

+

+;;; uInt longest_match(deflate_state *deflatestate, IPos curmatch)

+

+;_longest_match:

+IFDEF NOOLDPENTIUMCODE

+    IFDEF NOUNDERLINE

+    longest_match       proc near

+    ELSE

+    _longest_match      proc near

+    ENDIF

+ELSE

+    IFDEF NOUNDERLINE

+    longest_match_686   proc near

+    ELSE

+    _longest_match_686  proc near

+    ENDIF

+ENDIF

+

+;;; Save registers that the compiler may be using, and adjust esp to

+;;; make room for our stack frame.

+

+        push    ebp

+        push    edi

+        push    esi

+        push    ebx

+        sub esp, LocalVarsSize

+

+;;; Retrieve the function arguments. ecx will hold cur_match

+;;; throughout the entire function. edx will hold the pointer to the

+;;; deflate_state structure during the function's setup (before

+;;; entering the main loop.

+

+        mov edx, [deflatestate]

+        mov ecx, [curmatch]

+

+;;; uInt wmask = s->w_mask;

+;;; unsigned chain_length = s->max_chain_length;

+;;; if (s->prev_length >= s->good_match) {

+;;;     chain_length >>= 2;

+;;; }

+

+        mov eax, [edx + dsPrevLen]

+        mov ebx, [edx + dsGoodMatch]

+        cmp eax, ebx

+        mov eax, [edx + dsWMask]

+        mov ebx, [edx + dsMaxChainLen]

+        jl  LastMatchGood

+        shr ebx, 2

+LastMatchGood:

+

+;;; chainlen is decremented once beforehand so that the function can

+;;; use the sign flag instead of the zero flag for the exit test.

+;;; It is then shifted into the high word, to make room for the wmask

+;;; value, which it will always accompany.

+

+        dec ebx

+        shl ebx, 16

+        or  ebx, eax

+        mov [chainlenwmask], ebx

+

+;;; if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;

+

+        mov eax, [edx + dsNiceMatch]

+        mov ebx, [edx + dsLookahead]

+        cmp ebx, eax

+        jl  LookaheadLess

+        mov ebx, eax

+LookaheadLess:  mov [nicematch], ebx

+

+;;; register Bytef *scan = s->window + s->strstart;

+

+        mov esi, [edx + dsWindow]

+        mov [window], esi

+        mov ebp, [edx + dsStrStart]

+        lea edi, [esi + ebp]

+        mov [scan], edi

+

+;;; Determine how many bytes the scan ptr is off from being

+;;; dword-aligned.

+

+        mov eax, edi

+        neg eax

+        and eax, 3

+        mov [scanalign], eax

+

+;;; IPos limit = s->strstart > (IPos)MAX_DIST(s) ?

+;;;     s->strstart - (IPos)MAX_DIST(s) : NIL;

+

+        mov eax, [edx + dsWSize]

+        sub eax, MIN_LOOKAHEAD

+        sub ebp, eax

+        jg  LimitPositive

+        xor ebp, ebp

+LimitPositive:

+

+;;; int best_len = s->prev_length;

+

+        mov eax, [edx + dsPrevLen]

+        mov [bestlen], eax

+

+;;; Store the sum of s->window + best_len in esi locally, and in esi.

+

+        add esi, eax

+        mov [windowbestlen], esi

+

+;;; register ush scan_start = *(ushf*)scan;

+;;; register ush scan_end   = *(ushf*)(scan+best_len-1);

+;;; Posf *prev = s->prev;

+

+        movzx   ebx, word ptr [edi]

+        mov [scanstart], ebx

+        movzx   ebx, word ptr [edi + eax - 1]

+        mov [scanend], ebx

+        mov edi, [edx + dsPrev]

+

+;;; Jump into the main loop.

+

+        mov edx, [chainlenwmask]

+        jmp short LoopEntry

+

+align 4

+

+;;; do {

+;;;     match = s->window + cur_match;

+;;;     if (*(ushf*)(match+best_len-1) != scan_end ||

+;;;         *(ushf*)match != scan_start) continue;

+;;;     [...]

+;;; } while ((cur_match = prev[cur_match & wmask]) > limit

+;;;          && --chain_length != 0);

+;;;

+;;; Here is the inner loop of the function. The function will spend the

+;;; majority of its time in this loop, and majority of that time will

+;;; be spent in the first ten instructions.

+;;;

+;;; Within this loop:

+;;; ebx = scanend

+;;; ecx = curmatch

+;;; edx = chainlenwmask - i.e., ((chainlen << 16) | wmask)

+;;; esi = windowbestlen - i.e., (window + bestlen)

+;;; edi = prev

+;;; ebp = limit

+

+LookupLoop:

+        and ecx, edx

+        movzx   ecx, word ptr [edi + ecx*2]

+        cmp ecx, ebp

+        jbe LeaveNow

+        sub edx, 00010000h

+        js  LeaveNow

+LoopEntry:  movzx   eax, word ptr [esi + ecx - 1]

+        cmp eax, ebx

+        jnz LookupLoop

+        mov eax, [window]

+        movzx   eax, word ptr [eax + ecx]

+        cmp eax, [scanstart]

+        jnz LookupLoop

+

+;;; Store the current value of chainlen.

+

+        mov [chainlenwmask], edx

+

+;;; Point edi to the string under scrutiny, and esi to the string we

+;;; are hoping to match it up with. In actuality, esi and edi are

+;;; both pointed (MAX_MATCH_8 - scanalign) bytes ahead, and edx is

+;;; initialized to -(MAX_MATCH_8 - scanalign).

+

+        mov esi, [window]

+        mov edi, [scan]

+        add esi, ecx

+        mov eax, [scanalign]

+        mov edx, 0fffffef8h; -(MAX_MATCH_8)

+        lea edi, [edi + eax + 0108h] ;MAX_MATCH_8]

+        lea esi, [esi + eax + 0108h] ;MAX_MATCH_8]

+

+;;; Test the strings for equality, 8 bytes at a time. At the end,

+;;; adjust edx so that it is offset to the exact byte that mismatched.

+;;;

+;;; We already know at this point that the first three bytes of the

+;;; strings match each other, and they can be safely passed over before

+;;; starting the compare loop. So what this code does is skip over 0-3

+;;; bytes, as much as necessary in order to dword-align the edi

+;;; pointer. (esi will still be misaligned three times out of four.)

+;;;

+;;; It should be confessed that this loop usually does not represent

+;;; much of the total running time. Replacing it with a more

+;;; straightforward "rep cmpsb" would not drastically degrade

+;;; performance.

+

+LoopCmps:

+        mov eax, [esi + edx]

+        xor eax, [edi + edx]

+        jnz LeaveLoopCmps

+        mov eax, [esi + edx + 4]

+        xor eax, [edi + edx + 4]

+        jnz LeaveLoopCmps4

+        add edx, 8

+        jnz LoopCmps

+        jmp short LenMaximum

+LeaveLoopCmps4: add edx, 4

+LeaveLoopCmps:  test    eax, 0000FFFFh

+        jnz LenLower

+        add edx,  2

+        shr eax, 16

+LenLower:   sub al, 1

+        adc edx, 0

+

+;;; Calculate the length of the match. If it is longer than MAX_MATCH,

+;;; then automatically accept it as the best possible match and leave.

+

+        lea eax, [edi + edx]

+        mov edi, [scan]

+        sub eax, edi

+        cmp eax, MAX_MATCH

+        jge LenMaximum

+

+;;; If the length of the match is not longer than the best match we

+;;; have so far, then forget it and return to the lookup loop.

+

+        mov edx, [deflatestate]

+        mov ebx, [bestlen]

+        cmp eax, ebx

+        jg  LongerMatch

+        mov esi, [windowbestlen]

+        mov edi, [edx + dsPrev]

+        mov ebx, [scanend]

+        mov edx, [chainlenwmask]

+        jmp LookupLoop

+

+;;;         s->match_start = cur_match;

+;;;         best_len = len;

+;;;         if (len >= nice_match) break;

+;;;         scan_end = *(ushf*)(scan+best_len-1);

+

+LongerMatch:    mov ebx, [nicematch]

+        mov [bestlen], eax

+        mov [edx + dsMatchStart], ecx

+        cmp eax, ebx

+        jge LeaveNow

+        mov esi, [window]

+        add esi, eax

+        mov [windowbestlen], esi

+        movzx   ebx, word ptr [edi + eax - 1]

+        mov edi, [edx + dsPrev]

+        mov [scanend], ebx

+        mov edx, [chainlenwmask]

+        jmp LookupLoop

+

+;;; Accept the current string, with the maximum possible length.

+

+LenMaximum: mov edx, [deflatestate]

+        mov dword ptr [bestlen], MAX_MATCH

+        mov [edx + dsMatchStart], ecx

+

+;;; if ((uInt)best_len <= s->lookahead) return (uInt)best_len;

+;;; return s->lookahead;

+

+LeaveNow:

+        mov edx, [deflatestate]

+        mov ebx, [bestlen]

+        mov eax, [edx + dsLookahead]

+        cmp ebx, eax

+        jg  LookaheadRet

+        mov eax, ebx

+LookaheadRet:

+

+;;; Restore the stack and return from whence we came.

+

+        add esp, LocalVarsSize

+        pop ebx

+        pop esi

+        pop edi

+        pop ebp

+

+        ret

+; please don't remove this string !

+; Your can freely use gvmat32 in any free or commercial app if you don't remove the string in the binary!

+    db     0dh,0ah,"asm686 with masm, optimised assembly code from Brian Raiter, written 1998",0dh,0ah

+

+

+IFDEF NOOLDPENTIUMCODE

+    IFDEF NOUNDERLINE

+    longest_match       endp

+    ELSE

+    _longest_match      endp

+    ENDIF

+

+    IFDEF NOUNDERLINE

+    match_init      proc near

+                    ret

+    match_init      endp

+    ELSE

+    _match_init     proc near

+                    ret

+    _match_init     endp

+    ENDIF    

+ELSE

+    IFDEF NOUNDERLINE

+    longest_match_686   endp

+    ELSE

+    _longest_match_686  endp

+    ENDIF

+ENDIF

+

+_TEXT   ends

+end

diff --git a/gs/zlib/contrib/masmx86/gvmat32.obj b/gs/zlib/contrib/masmx86/gvmat32.obj
new file mode 100644
index 000000000..ebb326238
--- /dev/null
+++ b/gs/zlib/contrib/masmx86/gvmat32.obj
diff --git a/gs/zlib/contrib/masmx86/gvmat32c.c b/gs/zlib/contrib/masmx86/gvmat32c.c
new file mode 100644
index 000000000..7ad2b2794
--- /dev/null
+++ b/gs/zlib/contrib/masmx86/gvmat32c.c
@@ -0,0 +1,62 @@
+/* gvmat32.c -- C portion of the optimized longest_match for 32 bits x86

+ * Copyright (C) 1995-1996 Jean-loup Gailly and Gilles Vollant.

+ * File written by Gilles Vollant, by modifiying the longest_match

+ *  from Jean-loup Gailly in deflate.c

+ *  it prepare all parameters and call the assembly longest_match_gvasm

+ *  longest_match execute standard C code is wmask != 0x7fff

+ *     (assembly code is faster with a fixed wmask)

+ *

+ * Read comment at beginning of gvmat32.asm for more information

+ */

+

+#if defined(ASMV) && (!defined(NOOLDPENTIUMCODE))

+#include "deflate.h"

+

+/* if your C compiler don't add underline before function name,

+        define ADD_UNDERLINE_ASMFUNC */

+#ifdef ADD_UNDERLINE_ASMFUNC

+#define longest_match_7fff _longest_match_7fff

+#define longest_match_686  _longest_match_686

+#define cpudetect32        _cpudetect32

+#endif

+

+

+unsigned long cpudetect32();

+

+uInt longest_match_c(

+    deflate_state *s,

+    IPos cur_match);                             /* current match */

+

+

+uInt longest_match_7fff(

+    deflate_state *s,

+    IPos cur_match);                             /* current match */

+

+uInt longest_match_686(

+    deflate_state *s,

+    IPos cur_match);                             /* current match */

+

+

+static uInt iIsPPro=2;

+

+void match_init ()

+{

+    iIsPPro = (((cpudetect32()/0x100)&0xf)>=6) ? 1 : 0;

+}

+

+uInt longest_match(

+    deflate_state *s,

+    IPos cur_match)                             /* current match */

+{

+    if (iIsPPro!=0)

+        return longest_match_686(s,cur_match);

+

+    if (s->w_mask != 0x7fff)

+        return longest_match_686(s,cur_match);

+

+    /* now ((s->w_mask == 0x7fff) && (iIsPPro==0)) */

+        return longest_match_7fff(s,cur_match);

+}

+

+

+#endif /* defined(ASMV) && (!defined(NOOLDPENTIUMCODE)) */

diff --git a/gs/zlib/contrib/masmx86/inffas32.asm b/gs/zlib/contrib/masmx86/inffas32.asm
new file mode 100644
index 000000000..4a205125e
--- /dev/null
+++ b/gs/zlib/contrib/masmx86/inffas32.asm
@@ -0,0 +1,1083 @@
+;/* inffas32.asm is a hand tuned assembler version of inffast.c -- fast decoding

+; *

+; * inffas32.asm is derivated from inffas86.c, with translation of assembly code

+; *

+; * Copyright (C) 1995-2003 Mark Adler

+; * For conditions of distribution and use, see copyright notice in zlib.h

+; *

+; * Copyright (C) 2003 Chris Anderson <christop@charm.net>

+; * Please use the copyright conditions above.

+; *

+; * Mar-13-2003 -- Most of this is derived from inffast.S which is derived from

+; * the gcc -S output of zlib-1.2.0/inffast.c.  Zlib-1.2.0 is in beta release at

+; * the moment.  I have successfully compiled and tested this code with gcc2.96,

+; * gcc3.2, icc5.0, msvc6.0.  It is very close to the speed of inffast.S

+; * compiled with gcc -DNO_MMX, but inffast.S is still faster on the P3 with MMX

+; * enabled.  I will attempt to merge the MMX code into this version.  Newer

+; * versions of this and inffast.S can be found at

+; * http://www.eetbeetee.com/zlib/ and http://www.charm.net/~christop/zlib/

+; * 

+; * 2005 : modification by Gilles Vollant

+; */

+; For Visual C++ 4.x and higher and ML 6.x and higher

+;   ml.exe is in directory \MASM611C of Win95 DDK

+;   ml.exe is also distributed in http://www.masm32.com/masmdl.htm

+;    and in VC++2003 toolkit at http://msdn.microsoft.com/visualc/vctoolkit2003/

+;

+;

+;   compile with command line option

+;   ml  /coff /Zi /c /Flinffas32.lst inffas32.asm

+

+;   if you define NO_GZIP (see inflate.h), compile with

+;   ml  /coff /Zi /c /Flinffas32.lst /DNO_GUNZIP inffas32.asm

+

+

+; zlib122sup is 0 fort zlib 1.2.2.1 and lower

+; zlib122sup is 8 fort zlib 1.2.2.2 and more (with addition of dmax and head 

+;        in inflate_state in inflate.h)

+zlib1222sup      equ    8

+

+

+IFDEF GUNZIP

+  INFLATE_MODE_TYPE    equ 11

+  INFLATE_MODE_BAD     equ 26

+ELSE

+  IFNDEF NO_GUNZIP

+    INFLATE_MODE_TYPE    equ 11

+    INFLATE_MODE_BAD     equ 26

+  ELSE

+    INFLATE_MODE_TYPE    equ 3

+    INFLATE_MODE_BAD     equ 17

+  ENDIF

+ENDIF

+

+

+; 75 "inffast.S"

+;FILE "inffast.S"

+

+;;;GLOBAL _inflate_fast

+

+;;;SECTION .text

+

+

+

+	.586p

+	.mmx

+

+	name	inflate_fast_x86

+	.MODEL	FLAT

+

+_DATA			segment

+inflate_fast_use_mmx:

+	dd	1

+

+

+_TEXT			segment

+PUBLIC _inflate_fast

+

+ALIGN 4

+_inflate_fast:

+	jmp inflate_fast_entry

+

+

+

+ALIGN 4

+	db	'Fast decoding Code from Chris Anderson'

+	db	0

+

+ALIGN 4

+invalid_literal_length_code_msg:

+	db	'invalid literal/length code'

+	db	0

+

+ALIGN 4

+invalid_distance_code_msg:

+	db	'invalid distance code'

+	db	0

+

+ALIGN 4

+invalid_distance_too_far_msg:

+	db	'invalid distance too far back'

+	db	0

+

+

+ALIGN 4

+inflate_fast_mask:

+dd	0

+dd	1

+dd	3

+dd	7

+dd	15

+dd	31

+dd	63

+dd	127

+dd	255

+dd	511

+dd	1023

+dd	2047

+dd	4095

+dd	8191

+dd	16383

+dd	32767

+dd	65535

+dd	131071

+dd	262143

+dd	524287

+dd	1048575

+dd	2097151

+dd	4194303

+dd	8388607

+dd	16777215

+dd	33554431

+dd	67108863

+dd	134217727

+dd	268435455

+dd	536870911

+dd	1073741823

+dd	2147483647

+dd	4294967295

+

+

+mode_state	 equ	0	;/* state->mode	*/

+wsize_state	 equ	(32+zlib1222sup)	;/* state->wsize */

+write_state	 equ	(36+4+zlib1222sup)	;/* state->write */

+window_state	 equ	(40+4+zlib1222sup)	;/* state->window */

+hold_state	 equ	(44+4+zlib1222sup)	;/* state->hold	*/

+bits_state	 equ	(48+4+zlib1222sup)	;/* state->bits	*/

+lencode_state	 equ	(64+4+zlib1222sup)	;/* state->lencode */

+distcode_state	 equ	(68+4+zlib1222sup)	;/* state->distcode */

+lenbits_state	 equ	(72+4+zlib1222sup)	;/* state->lenbits */

+distbits_state	 equ	(76+4+zlib1222sup)	;/* state->distbits */

+

+

+;;SECTION .text

+; 205 "inffast.S"

+;GLOBAL	inflate_fast_use_mmx

+

+;SECTION .data

+

+

+; GLOBAL inflate_fast_use_mmx:object

+;.size inflate_fast_use_mmx, 4

+; 226 "inffast.S"

+;SECTION .text

+

+ALIGN 4

+inflate_fast_entry:

+	push  edi

+	push  esi

+	push  ebp

+	push  ebx

+	pushfd

+	sub  esp,64

+	cld

+

+

+

+

+	mov  esi, [esp+88]

+	mov  edi, [esi+28]

+

+

+

+

+

+

+

+	mov  edx, [esi+4]

+	mov  eax, [esi+0]

+

+	add  edx,eax

+	sub  edx,11

+

+	mov  [esp+44],eax

+	mov  [esp+20],edx

+

+	mov  ebp, [esp+92]

+	mov  ecx, [esi+16]

+	mov  ebx, [esi+12]

+

+	sub  ebp,ecx

+	neg  ebp

+	add  ebp,ebx

+

+	sub  ecx,257

+	add  ecx,ebx

+

+	mov  [esp+60],ebx

+	mov  [esp+40],ebp

+	mov  [esp+16],ecx

+; 285 "inffast.S"

+	mov  eax, [edi+lencode_state]

+	mov  ecx, [edi+distcode_state]

+

+	mov  [esp+8],eax

+	mov  [esp+12],ecx

+

+	mov  eax,1

+	mov  ecx, [edi+lenbits_state]

+	shl  eax,cl

+	dec  eax

+	mov  [esp+0],eax

+

+	mov  eax,1

+	mov  ecx, [edi+distbits_state]

+	shl  eax,cl

+	dec  eax

+	mov  [esp+4],eax

+

+	mov  eax, [edi+wsize_state]

+	mov  ecx, [edi+write_state]

+	mov  edx, [edi+window_state]

+

+	mov  [esp+52],eax

+	mov  [esp+48],ecx

+	mov  [esp+56],edx

+

+	mov  ebp, [edi+hold_state]

+	mov  ebx, [edi+bits_state]

+; 321 "inffast.S"

+	mov  esi, [esp+44]

+	mov  ecx, [esp+20]

+	cmp  ecx,esi

+	ja   L_align_long

+

+	add  ecx,11

+	sub  ecx,esi

+	mov  eax,12

+	sub  eax,ecx

+	lea  edi, [esp+28]

+	rep movsb

+	mov  ecx,eax

+	xor  eax,eax

+	rep stosb

+	lea  esi, [esp+28]

+	mov  [esp+20],esi

+	jmp  L_is_aligned

+

+

+L_align_long:

+	test  esi,3

+	jz   L_is_aligned

+	xor  eax,eax

+	mov  al, [esi]

+	inc  esi

+	mov  ecx,ebx

+	add  ebx,8

+	shl  eax,cl

+	or  ebp,eax

+	jmp L_align_long

+

+L_is_aligned:

+	mov  edi, [esp+60]

+; 366 "inffast.S"

+L_check_mmx:

+	cmp  dword ptr [inflate_fast_use_mmx],2

+	je   L_init_mmx

+	ja   L_do_loop

+

+	push  eax

+	push  ebx

+	push  ecx

+	push  edx

+	pushfd

+	mov  eax, [esp]

+	xor  dword ptr [esp],0200000h

+

+

+

+

+	popfd

+	pushfd

+	pop  edx

+	xor  edx,eax

+	jz   L_dont_use_mmx

+	xor  eax,eax

+	cpuid

+	cmp  ebx,0756e6547h

+	jne  L_dont_use_mmx

+	cmp  ecx,06c65746eh

+	jne  L_dont_use_mmx

+	cmp  edx,049656e69h

+	jne  L_dont_use_mmx

+	mov  eax,1

+	cpuid

+	shr  eax,8

+	and  eax,15

+	cmp  eax,6

+	jne  L_dont_use_mmx

+	test  edx,0800000h

+	jnz  L_use_mmx

+	jmp  L_dont_use_mmx

+L_use_mmx:

+	mov  dword ptr [inflate_fast_use_mmx],2

+	jmp  L_check_mmx_pop

+L_dont_use_mmx:

+	mov  dword ptr [inflate_fast_use_mmx],3

+L_check_mmx_pop:

+	pop  edx

+	pop  ecx

+	pop  ebx

+	pop  eax

+	jmp  L_check_mmx

+; 426 "inffast.S"

+ALIGN 4

+L_do_loop:

+; 437 "inffast.S"

+	cmp  bl,15

+	ja   L_get_length_code

+

+	xor  eax,eax

+	lodsw

+	mov  cl,bl

+	add  bl,16

+	shl  eax,cl

+	or  ebp,eax

+

+L_get_length_code:

+	mov  edx, [esp+0]

+	mov  ecx, [esp+8]

+	and  edx,ebp

+	mov  eax, [ecx+edx*4]

+

+L_dolen:

+

+

+

+

+

+

+	mov  cl,ah

+	sub  bl,ah

+	shr  ebp,cl

+

+

+

+

+

+

+	test  al,al

+	jnz   L_test_for_length_base

+

+	shr  eax,16

+	stosb

+

+L_while_test:

+

+

+	cmp  [esp+16],edi

+	jbe  L_break_loop

+

+	cmp  [esp+20],esi

+	ja   L_do_loop

+	jmp  L_break_loop

+

+L_test_for_length_base:

+; 502 "inffast.S"

+	mov  edx,eax

+	shr  edx,16

+	mov  cl,al

+

+	test  al,16

+	jz   L_test_for_second_level_length

+	and  cl,15

+	jz   L_save_len

+	cmp  bl,cl

+	jae  L_add_bits_to_len

+

+	mov  ch,cl

+	xor  eax,eax

+	lodsw

+	mov  cl,bl

+	add  bl,16

+	shl  eax,cl

+	or  ebp,eax

+	mov  cl,ch

+

+L_add_bits_to_len:

+	mov  eax,1

+	shl  eax,cl

+	dec  eax

+	sub  bl,cl

+	and  eax,ebp

+	shr  ebp,cl

+	add  edx,eax

+

+L_save_len:

+	mov  [esp+24],edx

+

+

+L_decode_distance:

+; 549 "inffast.S"

+	cmp  bl,15

+	ja   L_get_distance_code

+

+	xor  eax,eax

+	lodsw

+	mov  cl,bl

+	add  bl,16

+	shl  eax,cl

+	or  ebp,eax

+

+L_get_distance_code:

+	mov  edx, [esp+4]

+	mov  ecx, [esp+12]

+	and  edx,ebp

+	mov  eax, [ecx+edx*4]

+

+

+L_dodist:

+	mov  edx,eax

+	shr  edx,16

+	mov  cl,ah

+	sub  bl,ah

+	shr  ebp,cl

+; 584 "inffast.S"

+	mov  cl,al

+

+	test  al,16

+	jz  L_test_for_second_level_dist

+	and  cl,15

+	jz  L_check_dist_one

+	cmp  bl,cl

+	jae  L_add_bits_to_dist

+

+	mov  ch,cl

+	xor  eax,eax

+	lodsw

+	mov  cl,bl

+	add  bl,16

+	shl  eax,cl

+	or  ebp,eax

+	mov  cl,ch

+

+L_add_bits_to_dist:

+	mov  eax,1

+	shl  eax,cl

+	dec  eax

+	sub  bl,cl

+	and  eax,ebp

+	shr  ebp,cl

+	add  edx,eax

+	jmp  L_check_window

+

+L_check_window:

+; 625 "inffast.S"

+	mov  [esp+44],esi

+	mov  eax,edi

+	sub  eax, [esp+40]

+

+	cmp  eax,edx

+	jb   L_clip_window

+

+	mov  ecx, [esp+24]

+	mov  esi,edi

+	sub  esi,edx

+

+	sub  ecx,3

+	mov  al, [esi]

+	mov  [edi],al

+	mov  al, [esi+1]

+	mov  dl, [esi+2]

+	add  esi,3

+	mov  [edi+1],al

+	mov  [edi+2],dl

+	add  edi,3

+	rep movsb

+

+	mov  esi, [esp+44]

+	jmp  L_while_test

+

+ALIGN 4

+L_check_dist_one:

+	cmp  edx,1

+	jne  L_check_window

+	cmp  [esp+40],edi

+	je  L_check_window

+

+	dec  edi

+	mov  ecx, [esp+24]

+	mov  al, [edi]

+	sub  ecx,3

+

+	mov  [edi+1],al

+	mov  [edi+2],al

+	mov  [edi+3],al

+	add  edi,4

+	rep stosb

+

+	jmp  L_while_test

+

+ALIGN 4

+L_test_for_second_level_length:

+

+

+

+

+	test  al,64

+	jnz   L_test_for_end_of_block

+

+	mov  eax,1

+	shl  eax,cl

+	dec  eax

+	and  eax,ebp

+	add  eax,edx

+	mov  edx, [esp+8]

+	mov  eax, [edx+eax*4]

+	jmp  L_dolen

+

+ALIGN 4

+L_test_for_second_level_dist:

+

+

+

+

+	test  al,64

+	jnz   L_invalid_distance_code

+

+	mov  eax,1

+	shl  eax,cl

+	dec  eax

+	and  eax,ebp

+	add  eax,edx

+	mov  edx, [esp+12]

+	mov  eax, [edx+eax*4]

+	jmp  L_dodist

+

+ALIGN 4

+L_clip_window:

+; 721 "inffast.S"

+	mov  ecx,eax

+	mov  eax, [esp+52]

+	neg  ecx

+	mov  esi, [esp+56]

+

+	cmp  eax,edx

+	jb   L_invalid_distance_too_far

+

+	add  ecx,edx

+	cmp  dword ptr [esp+48],0

+	jne  L_wrap_around_window

+

+	sub  eax,ecx

+	add  esi,eax

+; 749 "inffast.S"

+	mov  eax, [esp+24]

+	cmp  eax,ecx

+	jbe  L_do_copy1

+

+	sub  eax,ecx

+	rep movsb

+	mov  esi,edi

+	sub  esi,edx

+	jmp  L_do_copy1

+

+	cmp  eax,ecx

+	jbe  L_do_copy1

+

+	sub  eax,ecx

+	rep movsb

+	mov  esi,edi

+	sub  esi,edx

+	jmp  L_do_copy1

+

+L_wrap_around_window:

+; 793 "inffast.S"

+	mov  eax, [esp+48]

+	cmp  ecx,eax

+	jbe  L_contiguous_in_window

+

+	add  esi, [esp+52]

+	add  esi,eax

+	sub  esi,ecx

+	sub  ecx,eax

+

+

+	mov  eax, [esp+24]

+	cmp  eax,ecx

+	jbe  L_do_copy1

+

+	sub  eax,ecx

+	rep movsb

+	mov  esi, [esp+56]

+	mov  ecx, [esp+48]

+	cmp  eax,ecx

+	jbe  L_do_copy1

+

+	sub  eax,ecx

+	rep movsb

+	mov  esi,edi

+	sub  esi,edx

+	jmp  L_do_copy1

+

+L_contiguous_in_window:

+; 836 "inffast.S"

+	add  esi,eax

+	sub  esi,ecx

+

+

+	mov  eax, [esp+24]

+	cmp  eax,ecx

+	jbe  L_do_copy1

+

+	sub  eax,ecx

+	rep movsb

+	mov  esi,edi

+	sub  esi,edx

+

+L_do_copy1:

+; 862 "inffast.S"

+	mov  ecx,eax

+	rep movsb

+

+	mov  esi, [esp+44]

+	jmp  L_while_test

+; 878 "inffast.S"

+ALIGN 4

+L_init_mmx:

+	emms

+

+

+

+

+

+	movd mm0,ebp

+	mov  ebp,ebx

+; 896 "inffast.S"

+	movd mm4,[esp+0]

+	movq mm3,mm4

+	movd mm5,[esp+4]

+	movq mm2,mm5

+	pxor mm1,mm1

+	mov  ebx, [esp+8]

+	jmp  L_do_loop_mmx

+

+ALIGN 4

+L_do_loop_mmx:

+	psrlq mm0,mm1

+

+	cmp  ebp,32

+	ja  L_get_length_code_mmx

+

+	movd mm6,ebp

+	movd mm7,[esi]

+	add  esi,4

+	psllq mm7,mm6

+	add  ebp,32

+	por mm0,mm7

+

+L_get_length_code_mmx:

+	pand mm4,mm0

+	movd eax,mm4

+	movq mm4,mm3

+	mov  eax, [ebx+eax*4]

+

+L_dolen_mmx:

+	movzx  ecx,ah

+	movd mm1,ecx

+	sub  ebp,ecx

+

+	test  al,al

+	jnz L_test_for_length_base_mmx

+

+	shr  eax,16

+	stosb

+

+L_while_test_mmx:

+

+

+	cmp  [esp+16],edi

+	jbe L_break_loop

+

+	cmp  [esp+20],esi

+	ja L_do_loop_mmx

+	jmp L_break_loop

+

+L_test_for_length_base_mmx:

+

+	mov  edx,eax

+	shr  edx,16

+

+	test  al,16

+	jz  L_test_for_second_level_length_mmx

+	and  eax,15

+	jz L_decode_distance_mmx

+

+	psrlq mm0,mm1

+	movd mm1,eax

+	movd ecx,mm0

+	sub  ebp,eax

+	and  ecx, [inflate_fast_mask+eax*4]

+	add  edx,ecx

+

+L_decode_distance_mmx:

+	psrlq mm0,mm1

+

+	cmp  ebp,32

+	ja L_get_dist_code_mmx

+

+	movd mm6,ebp

+	movd mm7,[esi]

+	add  esi,4

+	psllq mm7,mm6

+	add  ebp,32

+	por mm0,mm7

+

+L_get_dist_code_mmx:

+	mov  ebx, [esp+12]

+	pand mm5,mm0

+	movd eax,mm5

+	movq mm5,mm2

+	mov  eax, [ebx+eax*4]

+

+L_dodist_mmx:

+

+	movzx  ecx,ah

+	mov  ebx,eax

+	shr  ebx,16

+	sub  ebp,ecx

+	movd mm1,ecx

+

+	test  al,16

+	jz L_test_for_second_level_dist_mmx

+	and  eax,15

+	jz L_check_dist_one_mmx

+

+L_add_bits_to_dist_mmx:

+	psrlq mm0,mm1

+	movd mm1,eax

+	movd ecx,mm0

+	sub  ebp,eax

+	and  ecx, [inflate_fast_mask+eax*4]

+	add  ebx,ecx

+

+L_check_window_mmx:

+	mov  [esp+44],esi

+	mov  eax,edi

+	sub  eax, [esp+40]

+

+	cmp  eax,ebx

+	jb L_clip_window_mmx

+

+	mov  ecx,edx

+	mov  esi,edi

+	sub  esi,ebx

+

+	sub  ecx,3

+	mov  al, [esi]

+	mov  [edi],al

+	mov  al, [esi+1]

+	mov  dl, [esi+2]

+	add  esi,3

+	mov  [edi+1],al

+	mov  [edi+2],dl

+	add  edi,3

+	rep movsb

+

+	mov  esi, [esp+44]

+	mov  ebx, [esp+8]

+	jmp  L_while_test_mmx

+

+ALIGN 4

+L_check_dist_one_mmx:

+	cmp  ebx,1

+	jne  L_check_window_mmx

+	cmp  [esp+40],edi

+	je   L_check_window_mmx

+

+	dec  edi

+	mov  ecx,edx

+	mov  al, [edi]

+	sub  ecx,3

+

+	mov  [edi+1],al

+	mov  [edi+2],al

+	mov  [edi+3],al

+	add  edi,4

+	rep stosb

+

+	mov  ebx, [esp+8]

+	jmp  L_while_test_mmx

+

+ALIGN 4

+L_test_for_second_level_length_mmx:

+	test  al,64

+	jnz L_test_for_end_of_block

+

+	and  eax,15

+	psrlq mm0,mm1

+	movd ecx,mm0

+	and  ecx, [inflate_fast_mask+eax*4]

+	add  ecx,edx

+	mov  eax, [ebx+ecx*4]

+	jmp L_dolen_mmx

+

+ALIGN 4

+L_test_for_second_level_dist_mmx:

+	test  al,64

+	jnz L_invalid_distance_code

+

+	and  eax,15

+	psrlq mm0,mm1

+	movd ecx,mm0

+	and  ecx, [inflate_fast_mask+eax*4]

+	mov  eax, [esp+12]

+	add  ecx,ebx

+	mov  eax, [eax+ecx*4]

+	jmp  L_dodist_mmx

+

+ALIGN 4

+L_clip_window_mmx:

+

+	mov  ecx,eax

+	mov  eax, [esp+52]

+	neg  ecx

+	mov  esi, [esp+56]

+

+	cmp  eax,ebx

+	jb  L_invalid_distance_too_far

+

+	add  ecx,ebx

+	cmp  dword ptr [esp+48],0

+	jne  L_wrap_around_window_mmx

+

+	sub  eax,ecx

+	add  esi,eax

+

+	cmp  edx,ecx

+	jbe  L_do_copy1_mmx

+

+	sub  edx,ecx

+	rep movsb

+	mov  esi,edi

+	sub  esi,ebx

+	jmp  L_do_copy1_mmx

+

+	cmp  edx,ecx

+	jbe  L_do_copy1_mmx

+

+	sub  edx,ecx

+	rep movsb

+	mov  esi,edi

+	sub  esi,ebx

+	jmp  L_do_copy1_mmx

+

+L_wrap_around_window_mmx:

+

+	mov  eax, [esp+48]

+	cmp  ecx,eax

+	jbe  L_contiguous_in_window_mmx

+

+	add  esi, [esp+52]

+	add  esi,eax

+	sub  esi,ecx

+	sub  ecx,eax

+

+

+	cmp  edx,ecx

+	jbe  L_do_copy1_mmx

+

+	sub  edx,ecx

+	rep movsb

+	mov  esi, [esp+56]

+	mov  ecx, [esp+48]

+	cmp  edx,ecx

+	jbe  L_do_copy1_mmx

+

+	sub  edx,ecx

+	rep movsb

+	mov  esi,edi

+	sub  esi,ebx

+	jmp  L_do_copy1_mmx

+

+L_contiguous_in_window_mmx:

+

+	add  esi,eax

+	sub  esi,ecx

+

+

+	cmp  edx,ecx

+	jbe  L_do_copy1_mmx

+

+	sub  edx,ecx

+	rep movsb

+	mov  esi,edi

+	sub  esi,ebx

+

+L_do_copy1_mmx:

+

+

+	mov  ecx,edx

+	rep movsb

+

+	mov  esi, [esp+44]

+	mov  ebx, [esp+8]

+	jmp  L_while_test_mmx

+; 1174 "inffast.S"

+L_invalid_distance_code:

+

+

+

+

+

+	mov  ecx, invalid_distance_code_msg

+	mov  edx,INFLATE_MODE_BAD

+	jmp  L_update_stream_state

+

+L_test_for_end_of_block:

+

+

+

+

+

+	test  al,32

+	jz  L_invalid_literal_length_code

+

+	mov  ecx,0

+	mov  edx,INFLATE_MODE_TYPE

+	jmp  L_update_stream_state

+

+L_invalid_literal_length_code:

+

+

+

+

+

+	mov  ecx, invalid_literal_length_code_msg

+	mov  edx,INFLATE_MODE_BAD

+	jmp  L_update_stream_state

+

+L_invalid_distance_too_far:

+

+

+

+	mov  esi, [esp+44]

+	mov  ecx, invalid_distance_too_far_msg

+	mov  edx,INFLATE_MODE_BAD

+	jmp  L_update_stream_state

+

+L_update_stream_state:

+

+	mov  eax, [esp+88]

+	test  ecx,ecx

+	jz  L_skip_msg

+	mov  [eax+24],ecx

+L_skip_msg:

+	mov  eax, [eax+28]

+	mov  [eax+mode_state],edx

+	jmp  L_break_loop

+

+ALIGN 4

+L_break_loop:

+; 1243 "inffast.S"

+	cmp  dword ptr [inflate_fast_use_mmx],2

+	jne  L_update_next_in

+

+

+

+	mov  ebx,ebp

+

+L_update_next_in:

+; 1266 "inffast.S"

+	mov  eax, [esp+88]

+	mov  ecx,ebx

+	mov  edx, [eax+28]

+	shr  ecx,3

+	sub  esi,ecx

+	shl  ecx,3

+	sub  ebx,ecx

+	mov  [eax+12],edi

+	mov  [edx+bits_state],ebx

+	mov  ecx,ebx

+

+	lea  ebx, [esp+28]

+	cmp  [esp+20],ebx

+	jne  L_buf_not_used

+

+	sub  esi,ebx

+	mov  ebx, [eax+0]

+	mov  [esp+20],ebx

+	add  esi,ebx

+	mov  ebx, [eax+4]

+	sub  ebx,11

+	add  [esp+20],ebx

+

+L_buf_not_used:

+	mov  [eax+0],esi

+

+	mov  ebx,1

+	shl  ebx,cl

+	dec  ebx

+

+

+

+

+

+	cmp  dword ptr [inflate_fast_use_mmx],2

+	jne  L_update_hold

+

+

+

+	psrlq mm0,mm1

+	movd ebp,mm0

+

+	emms

+

+L_update_hold:

+

+

+

+	and  ebp,ebx

+	mov  [edx+hold_state],ebp

+

+

+

+

+	mov  ebx, [esp+20]

+	cmp  ebx,esi

+	jbe  L_last_is_smaller

+

+	sub  ebx,esi

+	add  ebx,11

+	mov  [eax+4],ebx

+	jmp  L_fixup_out

+L_last_is_smaller:

+	sub  esi,ebx

+	neg  esi

+	add  esi,11

+	mov  [eax+4],esi

+

+

+

+

+L_fixup_out:

+

+	mov  ebx, [esp+16]

+	cmp  ebx,edi

+	jbe  L_end_is_smaller

+

+	sub  ebx,edi

+	add  ebx,257

+	mov  [eax+16],ebx

+	jmp  L_done

+L_end_is_smaller:

+	sub  edi,ebx

+	neg  edi

+	add  edi,257

+	mov  [eax+16],edi

+

+

+

+

+

+L_done:

+	add  esp,64

+	popfd

+	pop  ebx

+	pop  ebp

+	pop  esi

+	pop  edi

+	ret

+

+_TEXT	ends

+end

diff --git a/gs/zlib/contrib/masmx86/inffas32.obj b/gs/zlib/contrib/masmx86/inffas32.obj
new file mode 100644
index 000000000..bd6664d11
--- /dev/null
+++ b/gs/zlib/contrib/masmx86/inffas32.obj
diff --git a/gs/zlib/contrib/masmx86/mkasm.bat b/gs/zlib/contrib/masmx86/mkasm.bat
new file mode 100755
index 000000000..70a51f837
--- /dev/null
+++ b/gs/zlib/contrib/masmx86/mkasm.bat
@@ -0,0 +1,3 @@
+cl /DASMV /I..\.. /O2 /c gvmat32c.c

+ml /coff /Zi /c /Flgvmat32.lst gvmat32.asm

+ml /coff /Zi /c /Flinffas32.lst inffas32.asm

diff --git a/gs/zlib/contrib/masmx86/readme.txt b/gs/zlib/contrib/masmx86/readme.txt
new file mode 100644
index 000000000..7b57167b7
--- /dev/null
+++ b/gs/zlib/contrib/masmx86/readme.txt
@@ -0,0 +1,21 @@
+
+Summary
+-------
+This directory contains ASM implementations of the functions
+longest_match() and inflate_fast().
+
+
+Use instructions
+----------------
+Copy these files into the zlib source directory, then run the
+appropriate makefile, as suggested below.
+
+
+Build instructions
+------------------
+* With Microsoft C and MASM:
+nmake -f win32/Makefile.msc LOC="-DASMV -DASMINF" OBJA="gvmat32c.obj gvmat32.obj inffas32.obj"
+
+* With Borland C and TASM:
+make -f win32/Makefile.bor LOCAL_ZLIB="-DASMV -DASMINF" OBJA="gvmat32c.obj gvmat32.obj inffas32.obj" OBJPA="+gvmat32c.obj+gvmat32.obj+inffas32.obj"
+
diff --git a/gs/zlib/contrib/minizip/ChangeLogUnzip b/gs/zlib/contrib/minizip/ChangeLogUnzip
new file mode 100644
index 000000000..50ca6a9e0
--- /dev/null
+++ b/gs/zlib/contrib/minizip/ChangeLogUnzip
@@ -0,0 +1,67 @@
+Change in 1.01e (12 feb 05)
+- Fix in zipOpen2 for globalcomment (Rolf Kalbermatter)
+- Fix possible memory leak in unzip.c (Zoran Stevanovic)
+
+Change in 1.01b (20 may 04)
+- Integrate patch from Debian package (submited by Mark Brown)
+- Add tools mztools from Xavier Roche
+
+Change in 1.01 (8 may 04)
+- fix buffer overrun risk in unzip.c (Xavier Roche)
+- fix a minor buffer insecurity in minizip.c (Mike Whittaker)
+
+Change in 1.00: (10 sept 03)
+- rename to 1.00
+- cosmetic code change
+
+Change in 0.22: (19 May 03)
+- crypting support (unless you define NOCRYPT)
+- append file in existing zipfile
+
+Change in 0.21: (10 Mar 03)
+- bug fixes
+
+Change in 0.17: (27 Jan 02)
+- bug fixes
+
+Change in 0.16: (19 Jan 02)
+- Support of ioapi for virtualize zip file access
+
+Change in 0.15: (19 Mar 98)
+- fix memory leak in minizip.c
+
+Change in 0.14: (10 Mar 98)
+- fix bugs in minizip.c sample for zipping big file
+- fix problem in month in date handling
+- fix bug in unzlocal_GetCurrentFileInfoInternal in unzip.c for
+    comment handling
+
+Change in 0.13: (6 Mar 98)
+- fix bugs in zip.c
+- add real minizip sample
+
+Change in 0.12: (4 Mar 98)
+- add zip.c and zip.h for creates .zip file
+- fix change_file_date in miniunz.c for Unix (Jean-loup Gailly)
+- fix miniunz.c for file without specific record for directory
+
+Change in 0.11: (3 Mar 98)
+- fix bug in unzGetCurrentFileInfo for get extra field and comment
+- enhance miniunz sample, remove the bad unztst.c sample
+
+Change in 0.10: (2 Mar 98)
+- fix bug in unzReadCurrentFile
+- rename unzip* to unz* function and structure
+- remove Windows-like hungary notation variable name
+- modify some structure in unzip.h
+- add somes comment in source
+- remove unzipGetcCurrentFile function
+- replace ZUNZEXPORT by ZEXPORT
+- add unzGetLocalExtrafield for get the local extrafield info
+- add a new sample, miniunz.c
+
+Change in 0.4: (25 Feb 98)
+- suppress the type unzipFileInZip.
+  Only on file in the zipfile can be open at the same time
+- fix somes typo in code
+- added tm_unz structure in unzip_file_info (date/time in readable format)
diff --git a/gs/zlib/contrib/minizip/Makefile b/gs/zlib/contrib/minizip/Makefile
new file mode 100644
index 000000000..84eaad20d
--- /dev/null
+++ b/gs/zlib/contrib/minizip/Makefile
@@ -0,0 +1,25 @@
+CC=cc
+CFLAGS=-O -I../..
+
+UNZ_OBJS = miniunz.o unzip.o ioapi.o ../../libz.a
+ZIP_OBJS = minizip.o zip.o   ioapi.o ../../libz.a
+
+.c.o:
+	$(CC) -c $(CFLAGS) $*.c
+
+all: miniunz minizip
+
+miniunz:  $(UNZ_OBJS)
+	$(CC) $(CFLAGS) -o $@ $(UNZ_OBJS)
+
+minizip:  $(ZIP_OBJS)
+	$(CC) $(CFLAGS) -o $@ $(ZIP_OBJS)
+
+test:	miniunz minizip
+	./minizip test readme.txt
+	./miniunz -l test.zip
+	mv readme.txt readme.old
+	./miniunz test.zip
+
+clean:
+	/bin/rm -f *.o *~ minizip miniunz
diff --git a/gs/zlib/contrib/minizip/crypt.h b/gs/zlib/contrib/minizip/crypt.h
new file mode 100644
index 000000000..622f4bc2e
--- /dev/null
+++ b/gs/zlib/contrib/minizip/crypt.h
@@ -0,0 +1,132 @@
+/* crypt.h -- base code for crypt/uncrypt ZIPfile
+
+
+   Version 1.01e, February 12th, 2005
+
+   Copyright (C) 1998-2005 Gilles Vollant
+
+   This code is a modified version of crypting code in Infozip distribution
+
+   The encryption/decryption parts of this source code (as opposed to the
+   non-echoing password parts) were originally written in Europe.  The
+   whole source package can be freely distributed, including from the USA.
+   (Prior to January 2000, re-export from the US was a violation of US law.)
+
+   This encryption code is a direct transcription of the algorithm from
+   Roger Schlafly, described by Phil Katz in the file appnote.txt.  This
+   file (appnote.txt) is distributed with the PKZIP program (even in the
+   version without encryption capabilities).
+
+   If you don't need crypting in your application, just define symbols
+   NOCRYPT and NOUNCRYPT.
+
+   This code support the "Traditional PKWARE Encryption".
+
+   The new AES encryption added on Zip format by Winzip (see the page
+   http://www.winzip.com/aes_info.htm ) and PKWare PKZip 5.x Strong
+   Encryption is not supported.
+*/
+
+#define CRC32(c, b) ((*(pcrc_32_tab+(((int)(c) ^ (b)) & 0xff))) ^ ((c) >> 8))
+
+/***********************************************************************
+ * Return the next byte in the pseudo-random sequence
+ */
+static int decrypt_byte(unsigned long* pkeys, const unsigned long* pcrc_32_tab)
+{
+    unsigned temp;  /* POTENTIAL BUG:  temp*(temp^1) may overflow in an
+                     * unpredictable manner on 16-bit systems; not a problem
+                     * with any known compiler so far, though */
+
+    temp = ((unsigned)(*(pkeys+2)) & 0xffff) | 2;
+    return (int)(((temp * (temp ^ 1)) >> 8) & 0xff);
+}
+
+/***********************************************************************
+ * Update the encryption keys with the next byte of plain text
+ */
+static int update_keys(unsigned long* pkeys,const unsigned long* pcrc_32_tab,int c)
+{
+    (*(pkeys+0)) = CRC32((*(pkeys+0)), c);
+    (*(pkeys+1)) += (*(pkeys+0)) & 0xff;
+    (*(pkeys+1)) = (*(pkeys+1)) * 134775813L + 1;
+    {
+      register int keyshift = (int)((*(pkeys+1)) >> 24);
+      (*(pkeys+2)) = CRC32((*(pkeys+2)), keyshift);
+    }
+    return c;
+}
+
+
+/***********************************************************************
+ * Initialize the encryption keys and the random header according to
+ * the given password.
+ */
+static void init_keys(const char* passwd,unsigned long* pkeys,const unsigned long* pcrc_32_tab)
+{
+    *(pkeys+0) = 305419896L;
+    *(pkeys+1) = 591751049L;
+    *(pkeys+2) = 878082192L;
+    while (*passwd != '\0') {
+        update_keys(pkeys,pcrc_32_tab,(int)*passwd);
+        passwd++;
+    }
+}
+
+#define zdecode(pkeys,pcrc_32_tab,c) \
+    (update_keys(pkeys,pcrc_32_tab,c ^= decrypt_byte(pkeys,pcrc_32_tab)))
+
+#define zencode(pkeys,pcrc_32_tab,c,t) \
+    (t=decrypt_byte(pkeys,pcrc_32_tab), update_keys(pkeys,pcrc_32_tab,c), t^(c))
+
+#ifdef INCLUDECRYPTINGCODE_IFCRYPTALLOWED
+
+#define RAND_HEAD_LEN  12
+   /* "last resort" source for second part of crypt seed pattern */
+#  ifndef ZCR_SEED2
+#    define ZCR_SEED2 3141592654UL     /* use PI as default pattern */
+#  endif
+
+static int crypthead(passwd, buf, bufSize, pkeys, pcrc_32_tab, crcForCrypting)
+    const char *passwd;         /* password string */
+    unsigned char *buf;         /* where to write header */
+    int bufSize;
+    unsigned long* pkeys;
+    const unsigned long* pcrc_32_tab;
+    unsigned long crcForCrypting;
+{
+    int n;                       /* index in random header */
+    int t;                       /* temporary */
+    int c;                       /* random byte */
+    unsigned char header[RAND_HEAD_LEN-2]; /* random header */
+    static unsigned calls = 0;   /* ensure different random header each time */
+
+    if (bufSize<RAND_HEAD_LEN)
+      return 0;
+
+    /* First generate RAND_HEAD_LEN-2 random bytes. We encrypt the
+     * output of rand() to get less predictability, since rand() is
+     * often poorly implemented.
+     */
+    if (++calls == 1)
+    {
+        srand((unsigned)(time(NULL) ^ ZCR_SEED2));
+    }
+    init_keys(passwd, pkeys, pcrc_32_tab);
+    for (n = 0; n < RAND_HEAD_LEN-2; n++)
+    {
+        c = (rand() >> 7) & 0xff;
+        header[n] = (unsigned char)zencode(pkeys, pcrc_32_tab, c, t);
+    }
+    /* Encrypt random header (last two bytes is high word of crc) */
+    init_keys(passwd, pkeys, pcrc_32_tab);
+    for (n = 0; n < RAND_HEAD_LEN-2; n++)
+    {
+        buf[n] = (unsigned char)zencode(pkeys, pcrc_32_tab, header[n], t);
+    }
+    buf[n++] = zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 16) & 0xff, t);
+    buf[n++] = zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 24) & 0xff, t);
+    return n;
+}
+
+#endif
diff --git a/gs/zlib/contrib/minizip/ioapi.c b/gs/zlib/contrib/minizip/ioapi.c
new file mode 100644
index 000000000..f1bee23e6
--- /dev/null
+++ b/gs/zlib/contrib/minizip/ioapi.c
@@ -0,0 +1,177 @@
+/* ioapi.c -- IO base function header for compress/uncompress .zip
+   files using zlib + zip or unzip API
+
+   Version 1.01e, February 12th, 2005
+
+   Copyright (C) 1998-2005 Gilles Vollant
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "zlib.h"
+#include "ioapi.h"
+
+
+
+/* I've found an old Unix (a SunOS 4.1.3_U1) without all SEEK_* defined.... */
+
+#ifndef SEEK_CUR
+#define SEEK_CUR    1
+#endif
+
+#ifndef SEEK_END
+#define SEEK_END    2
+#endif
+
+#ifndef SEEK_SET
+#define SEEK_SET    0
+#endif
+
+voidpf ZCALLBACK fopen_file_func OF((
+   voidpf opaque,
+   const char* filename,
+   int mode));
+
+uLong ZCALLBACK fread_file_func OF((
+   voidpf opaque,
+   voidpf stream,
+   void* buf,
+   uLong size));
+
+uLong ZCALLBACK fwrite_file_func OF((
+   voidpf opaque,
+   voidpf stream,
+   const void* buf,
+   uLong size));
+
+long ZCALLBACK ftell_file_func OF((
+   voidpf opaque,
+   voidpf stream));
+
+long ZCALLBACK fseek_file_func OF((
+   voidpf opaque,
+   voidpf stream,
+   uLong offset,
+   int origin));
+
+int ZCALLBACK fclose_file_func OF((
+   voidpf opaque,
+   voidpf stream));
+
+int ZCALLBACK ferror_file_func OF((
+   voidpf opaque,
+   voidpf stream));
+
+
+voidpf ZCALLBACK fopen_file_func (opaque, filename, mode)
+   voidpf opaque;
+   const char* filename;
+   int mode;
+{
+    FILE* file = NULL;
+    const char* mode_fopen = NULL;
+    if ((mode & ZLIB_FILEFUNC_MODE_READWRITEFILTER)==ZLIB_FILEFUNC_MODE_READ)
+        mode_fopen = "rb";
+    else
+    if (mode & ZLIB_FILEFUNC_MODE_EXISTING)
+        mode_fopen = "r+b";
+    else
+    if (mode & ZLIB_FILEFUNC_MODE_CREATE)
+        mode_fopen = "wb";
+
+    if ((filename!=NULL) && (mode_fopen != NULL))
+        file = fopen(filename, mode_fopen);
+    return file;
+}
+
+
+uLong ZCALLBACK fread_file_func (opaque, stream, buf, size)
+   voidpf opaque;
+   voidpf stream;
+   void* buf;
+   uLong size;
+{
+    uLong ret;
+    ret = (uLong)fread(buf, 1, (size_t)size, (FILE *)stream);
+    return ret;
+}
+
+
+uLong ZCALLBACK fwrite_file_func (opaque, stream, buf, size)
+   voidpf opaque;
+   voidpf stream;
+   const void* buf;
+   uLong size;
+{
+    uLong ret;
+    ret = (uLong)fwrite(buf, 1, (size_t)size, (FILE *)stream);
+    return ret;
+}
+
+long ZCALLBACK ftell_file_func (opaque, stream)
+   voidpf opaque;
+   voidpf stream;
+{
+    long ret;
+    ret = ftell((FILE *)stream);
+    return ret;
+}
+
+long ZCALLBACK fseek_file_func (opaque, stream, offset, origin)
+   voidpf opaque;
+   voidpf stream;
+   uLong offset;
+   int origin;
+{
+    int fseek_origin=0;
+    long ret;
+    switch (origin)
+    {
+    case ZLIB_FILEFUNC_SEEK_CUR :
+        fseek_origin = SEEK_CUR;
+        break;
+    case ZLIB_FILEFUNC_SEEK_END :
+        fseek_origin = SEEK_END;
+        break;
+    case ZLIB_FILEFUNC_SEEK_SET :
+        fseek_origin = SEEK_SET;
+        break;
+    default: return -1;
+    }
+    ret = 0;
+    fseek((FILE *)stream, offset, fseek_origin);
+    return ret;
+}
+
+int ZCALLBACK fclose_file_func (opaque, stream)
+   voidpf opaque;
+   voidpf stream;
+{
+    int ret;
+    ret = fclose((FILE *)stream);
+    return ret;
+}
+
+int ZCALLBACK ferror_file_func (opaque, stream)
+   voidpf opaque;
+   voidpf stream;
+{
+    int ret;
+    ret = ferror((FILE *)stream);
+    return ret;
+}
+
+void fill_fopen_filefunc (pzlib_filefunc_def)
+  zlib_filefunc_def* pzlib_filefunc_def;
+{
+    pzlib_filefunc_def->zopen_file = fopen_file_func;
+    pzlib_filefunc_def->zread_file = fread_file_func;
+    pzlib_filefunc_def->zwrite_file = fwrite_file_func;
+    pzlib_filefunc_def->ztell_file = ftell_file_func;
+    pzlib_filefunc_def->zseek_file = fseek_file_func;
+    pzlib_filefunc_def->zclose_file = fclose_file_func;
+    pzlib_filefunc_def->zerror_file = ferror_file_func;
+    pzlib_filefunc_def->opaque = NULL;
+}
diff --git a/gs/zlib/contrib/minizip/ioapi.h b/gs/zlib/contrib/minizip/ioapi.h
new file mode 100644
index 000000000..7d457baab
--- /dev/null
+++ b/gs/zlib/contrib/minizip/ioapi.h
@@ -0,0 +1,75 @@
+/* ioapi.h -- IO base function header for compress/uncompress .zip
+   files using zlib + zip or unzip API
+
+   Version 1.01e, February 12th, 2005
+
+   Copyright (C) 1998-2005 Gilles Vollant
+*/
+
+#ifndef _ZLIBIOAPI_H
+#define _ZLIBIOAPI_H
+
+
+#define ZLIB_FILEFUNC_SEEK_CUR (1)
+#define ZLIB_FILEFUNC_SEEK_END (2)
+#define ZLIB_FILEFUNC_SEEK_SET (0)
+
+#define ZLIB_FILEFUNC_MODE_READ      (1)
+#define ZLIB_FILEFUNC_MODE_WRITE     (2)
+#define ZLIB_FILEFUNC_MODE_READWRITEFILTER (3)
+
+#define ZLIB_FILEFUNC_MODE_EXISTING (4)
+#define ZLIB_FILEFUNC_MODE_CREATE   (8)
+
+
+#ifndef ZCALLBACK
+
+#if (defined(WIN32) || defined (WINDOWS) || defined (_WINDOWS)) && defined(CALLBACK) && defined (USEWINDOWS_CALLBACK)
+#define ZCALLBACK CALLBACK
+#else
+#define ZCALLBACK
+#endif
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef voidpf (ZCALLBACK *open_file_func) OF((voidpf opaque, const char* filename, int mode));
+typedef uLong  (ZCALLBACK *read_file_func) OF((voidpf opaque, voidpf stream, void* buf, uLong size));
+typedef uLong  (ZCALLBACK *write_file_func) OF((voidpf opaque, voidpf stream, const void* buf, uLong size));
+typedef long   (ZCALLBACK *tell_file_func) OF((voidpf opaque, voidpf stream));
+typedef long   (ZCALLBACK *seek_file_func) OF((voidpf opaque, voidpf stream, uLong offset, int origin));
+typedef int    (ZCALLBACK *close_file_func) OF((voidpf opaque, voidpf stream));
+typedef int    (ZCALLBACK *testerror_file_func) OF((voidpf opaque, voidpf stream));
+
+typedef struct zlib_filefunc_def_s
+{
+    open_file_func      zopen_file;
+    read_file_func      zread_file;
+    write_file_func     zwrite_file;
+    tell_file_func      ztell_file;
+    seek_file_func      zseek_file;
+    close_file_func     zclose_file;
+    testerror_file_func zerror_file;
+    voidpf              opaque;
+} zlib_filefunc_def;
+
+
+
+void fill_fopen_filefunc OF((zlib_filefunc_def* pzlib_filefunc_def));
+
+#define ZREAD(filefunc,filestream,buf,size) ((*((filefunc).zread_file))((filefunc).opaque,filestream,buf,size))
+#define ZWRITE(filefunc,filestream,buf,size) ((*((filefunc).zwrite_file))((filefunc).opaque,filestream,buf,size))
+#define ZTELL(filefunc,filestream) ((*((filefunc).ztell_file))((filefunc).opaque,filestream))
+#define ZSEEK(filefunc,filestream,pos,mode) ((*((filefunc).zseek_file))((filefunc).opaque,filestream,pos,mode))
+#define ZCLOSE(filefunc,filestream) ((*((filefunc).zclose_file))((filefunc).opaque,filestream))
+#define ZERROR(filefunc,filestream) ((*((filefunc).zerror_file))((filefunc).opaque,filestream))
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
diff --git a/gs/zlib/contrib/minizip/iowin32.c b/gs/zlib/contrib/minizip/iowin32.c
new file mode 100644
index 000000000..a9b5f7839
--- /dev/null
+++ b/gs/zlib/contrib/minizip/iowin32.c
@@ -0,0 +1,270 @@
+/* iowin32.c -- IO base function header for compress/uncompress .zip
+   files using zlib + zip or unzip API
+   This IO API version uses the Win32 API (for Microsoft Windows)
+
+   Version 1.01e, February 12th, 2005
+
+   Copyright (C) 1998-2005 Gilles Vollant
+*/
+
+#include <stdlib.h>
+
+#include "zlib.h"
+#include "ioapi.h"
+#include "iowin32.h"
+
+#ifndef INVALID_HANDLE_VALUE
+#define INVALID_HANDLE_VALUE (0xFFFFFFFF)
+#endif
+
+#ifndef INVALID_SET_FILE_POINTER
+#define INVALID_SET_FILE_POINTER ((DWORD)-1)
+#endif
+
+voidpf ZCALLBACK win32_open_file_func OF((
+   voidpf opaque,
+   const char* filename,
+   int mode));
+
+uLong ZCALLBACK win32_read_file_func OF((
+   voidpf opaque,
+   voidpf stream,
+   void* buf,
+   uLong size));
+
+uLong ZCALLBACK win32_write_file_func OF((
+   voidpf opaque,
+   voidpf stream,
+   const void* buf,
+   uLong size));
+
+long ZCALLBACK win32_tell_file_func OF((
+   voidpf opaque,
+   voidpf stream));
+
+long ZCALLBACK win32_seek_file_func OF((
+   voidpf opaque,
+   voidpf stream,
+   uLong offset,
+   int origin));
+
+int ZCALLBACK win32_close_file_func OF((
+   voidpf opaque,
+   voidpf stream));
+
+int ZCALLBACK win32_error_file_func OF((
+   voidpf opaque,
+   voidpf stream));
+
+typedef struct
+{
+    HANDLE hf;
+    int error;
+} WIN32FILE_IOWIN;
+
+voidpf ZCALLBACK win32_open_file_func (opaque, filename, mode)
+   voidpf opaque;
+   const char* filename;
+   int mode;
+{
+    const char* mode_fopen = NULL;
+    DWORD dwDesiredAccess,dwCreationDisposition,dwShareMode,dwFlagsAndAttributes ;
+    HANDLE hFile = 0;
+    voidpf ret=NULL;
+
+    dwDesiredAccess = dwShareMode = dwFlagsAndAttributes = 0;
+
+    if ((mode & ZLIB_FILEFUNC_MODE_READWRITEFILTER)==ZLIB_FILEFUNC_MODE_READ)
+    {
+        dwDesiredAccess = GENERIC_READ;
+        dwCreationDisposition = OPEN_EXISTING;
+        dwShareMode = FILE_SHARE_READ;
+    }
+    else
+    if (mode & ZLIB_FILEFUNC_MODE_EXISTING)
+    {
+        dwDesiredAccess = GENERIC_WRITE | GENERIC_READ;
+        dwCreationDisposition = OPEN_EXISTING;
+    }
+    else
+    if (mode & ZLIB_FILEFUNC_MODE_CREATE)
+    {
+        dwDesiredAccess = GENERIC_WRITE | GENERIC_READ;
+        dwCreationDisposition = CREATE_ALWAYS;
+    }
+
+    if ((filename!=NULL) && (dwDesiredAccess != 0))
+        hFile = CreateFile((LPCTSTR)filename, dwDesiredAccess, dwShareMode, NULL,
+                      dwCreationDisposition, dwFlagsAndAttributes, NULL);
+
+    if (hFile == INVALID_HANDLE_VALUE)
+        hFile = NULL;
+
+    if (hFile != NULL)
+    {
+        WIN32FILE_IOWIN w32fiow;
+        w32fiow.hf = hFile;
+        w32fiow.error = 0;
+        ret = malloc(sizeof(WIN32FILE_IOWIN));
+        if (ret==NULL)
+            CloseHandle(hFile);
+        else *((WIN32FILE_IOWIN*)ret) = w32fiow;
+    }
+    return ret;
+}
+
+
+uLong ZCALLBACK win32_read_file_func (opaque, stream, buf, size)
+   voidpf opaque;
+   voidpf stream;
+   void* buf;
+   uLong size;
+{
+    uLong ret=0;
+    HANDLE hFile = NULL;
+    if (stream!=NULL)
+        hFile = ((WIN32FILE_IOWIN*)stream) -> hf;
+    if (hFile != NULL)
+        if (!ReadFile(hFile, buf, size, &ret, NULL))
+        {
+            DWORD dwErr = GetLastError();
+            if (dwErr == ERROR_HANDLE_EOF)
+                dwErr = 0;
+            ((WIN32FILE_IOWIN*)stream) -> error=(int)dwErr;
+        }
+
+    return ret;
+}
+
+
+uLong ZCALLBACK win32_write_file_func (opaque, stream, buf, size)
+   voidpf opaque;
+   voidpf stream;
+   const void* buf;
+   uLong size;
+{
+    uLong ret=0;
+    HANDLE hFile = NULL;
+    if (stream!=NULL)
+        hFile = ((WIN32FILE_IOWIN*)stream) -> hf;
+
+    if (hFile !=NULL)
+        if (!WriteFile(hFile, buf, size, &ret, NULL))
+        {
+            DWORD dwErr = GetLastError();
+            if (dwErr == ERROR_HANDLE_EOF)
+                dwErr = 0;
+            ((WIN32FILE_IOWIN*)stream) -> error=(int)dwErr;
+        }
+
+    return ret;
+}
+
+long ZCALLBACK win32_tell_file_func (opaque, stream)
+   voidpf opaque;
+   voidpf stream;
+{
+    long ret=-1;
+    HANDLE hFile = NULL;
+    if (stream!=NULL)
+        hFile = ((WIN32FILE_IOWIN*)stream) -> hf;
+    if (hFile != NULL)
+    {
+        DWORD dwSet = SetFilePointer(hFile, 0, NULL, FILE_CURRENT);
+        if (dwSet == INVALID_SET_FILE_POINTER)
+        {
+            DWORD dwErr = GetLastError();
+            ((WIN32FILE_IOWIN*)stream) -> error=(int)dwErr;
+            ret = -1;
+        }
+        else
+            ret=(long)dwSet;
+    }
+    return ret;
+}
+
+long ZCALLBACK win32_seek_file_func (opaque, stream, offset, origin)
+   voidpf opaque;
+   voidpf stream;
+   uLong offset;
+   int origin;
+{
+    DWORD dwMoveMethod=0xFFFFFFFF;
+    HANDLE hFile = NULL;
+
+    long ret=-1;
+    if (stream!=NULL)
+        hFile = ((WIN32FILE_IOWIN*)stream) -> hf;
+    switch (origin)
+    {
+    case ZLIB_FILEFUNC_SEEK_CUR :
+        dwMoveMethod = FILE_CURRENT;
+        break;
+    case ZLIB_FILEFUNC_SEEK_END :
+        dwMoveMethod = FILE_END;
+        break;
+    case ZLIB_FILEFUNC_SEEK_SET :
+        dwMoveMethod = FILE_BEGIN;
+        break;
+    default: return -1;
+    }
+
+    if (hFile != NULL)
+    {
+        DWORD dwSet = SetFilePointer(hFile, offset, NULL, dwMoveMethod);
+        if (dwSet == INVALID_SET_FILE_POINTER)
+        {
+            DWORD dwErr = GetLastError();
+            ((WIN32FILE_IOWIN*)stream) -> error=(int)dwErr;
+            ret = -1;
+        }
+        else
+            ret=0;
+    }
+    return ret;
+}
+
+int ZCALLBACK win32_close_file_func (opaque, stream)
+   voidpf opaque;
+   voidpf stream;
+{
+    int ret=-1;
+
+    if (stream!=NULL)
+    {
+        HANDLE hFile;
+        hFile = ((WIN32FILE_IOWIN*)stream) -> hf;
+        if (hFile != NULL)
+        {
+            CloseHandle(hFile);
+            ret=0;
+        }
+        free(stream);
+    }
+    return ret;
+}
+
+int ZCALLBACK win32_error_file_func (opaque, stream)
+   voidpf opaque;
+   voidpf stream;
+{
+    int ret=-1;
+    if (stream!=NULL)
+    {
+        ret = ((WIN32FILE_IOWIN*)stream) -> error;
+    }
+    return ret;
+}
+
+void fill_win32_filefunc (pzlib_filefunc_def)
+  zlib_filefunc_def* pzlib_filefunc_def;
+{
+    pzlib_filefunc_def->zopen_file = win32_open_file_func;
+    pzlib_filefunc_def->zread_file = win32_read_file_func;
+    pzlib_filefunc_def->zwrite_file = win32_write_file_func;
+    pzlib_filefunc_def->ztell_file = win32_tell_file_func;
+    pzlib_filefunc_def->zseek_file = win32_seek_file_func;
+    pzlib_filefunc_def->zclose_file = win32_close_file_func;
+    pzlib_filefunc_def->zerror_file = win32_error_file_func;
+    pzlib_filefunc_def->opaque=NULL;
+}
diff --git a/gs/zlib/contrib/minizip/iowin32.h b/gs/zlib/contrib/minizip/iowin32.h
new file mode 100644
index 000000000..a3a437adf
--- /dev/null
+++ b/gs/zlib/contrib/minizip/iowin32.h
@@ -0,0 +1,21 @@
+/* iowin32.h -- IO base function header for compress/uncompress .zip
+   files using zlib + zip or unzip API
+   This IO API version uses the Win32 API (for Microsoft Windows)
+
+   Version 1.01e, February 12th, 2005
+
+   Copyright (C) 1998-2005 Gilles Vollant
+*/
+
+#include <windows.h>
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void fill_win32_filefunc OF((zlib_filefunc_def* pzlib_filefunc_def));
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/gs/zlib/contrib/minizip/miniunz.c b/gs/zlib/contrib/minizip/miniunz.c
new file mode 100644
index 000000000..f59993888
--- /dev/null
+++ b/gs/zlib/contrib/minizip/miniunz.c
@@ -0,0 +1,585 @@
+/*
+   miniunz.c
+   Version 1.01e, February 12th, 2005
+
+   Copyright (C) 1998-2005 Gilles Vollant
+*/
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <errno.h>
+#include <fcntl.h>
+
+#ifdef unix
+# include <unistd.h>
+# include <utime.h>
+#else
+# include <direct.h>
+# include <io.h>
+#endif
+
+#include "unzip.h"
+
+#define CASESENSITIVITY (0)
+#define WRITEBUFFERSIZE (8192)
+#define MAXFILENAME (256)
+
+#ifdef WIN32
+#define USEWIN32IOAPI
+#include "iowin32.h"
+#endif
+/*
+  mini unzip, demo of unzip package
+
+  usage :
+  Usage : miniunz [-exvlo] file.zip [file_to_extract] [-d extractdir]
+
+  list the file in the zipfile, and print the content of FILE_ID.ZIP or README.TXT
+    if it exists
+*/
+
+
+/* change_file_date : change the date/time of a file
+    filename : the filename of the file where date/time must be modified
+    dosdate : the new date at the MSDos format (4 bytes)
+    tmu_date : the SAME new date at the tm_unz format */
+void change_file_date(filename,dosdate,tmu_date)
+    const char *filename;
+    uLong dosdate;
+    tm_unz tmu_date;
+{
+#ifdef WIN32
+  HANDLE hFile;
+  FILETIME ftm,ftLocal,ftCreate,ftLastAcc,ftLastWrite;
+
+  hFile = CreateFile(filename,GENERIC_READ | GENERIC_WRITE,
+                      0,NULL,OPEN_EXISTING,0,NULL);
+  GetFileTime(hFile,&ftCreate,&ftLastAcc,&ftLastWrite);
+  DosDateTimeToFileTime((WORD)(dosdate>>16),(WORD)dosdate,&ftLocal);
+  LocalFileTimeToFileTime(&ftLocal,&ftm);
+  SetFileTime(hFile,&ftm,&ftLastAcc,&ftm);
+  CloseHandle(hFile);
+#else
+#ifdef unix
+  struct utimbuf ut;
+  struct tm newdate;
+  newdate.tm_sec = tmu_date.tm_sec;
+  newdate.tm_min=tmu_date.tm_min;
+  newdate.tm_hour=tmu_date.tm_hour;
+  newdate.tm_mday=tmu_date.tm_mday;
+  newdate.tm_mon=tmu_date.tm_mon;
+  if (tmu_date.tm_year > 1900)
+      newdate.tm_year=tmu_date.tm_year - 1900;
+  else
+      newdate.tm_year=tmu_date.tm_year ;
+  newdate.tm_isdst=-1;
+
+  ut.actime=ut.modtime=mktime(&newdate);
+  utime(filename,&ut);
+#endif
+#endif
+}
+
+
+/* mymkdir and change_file_date are not 100 % portable
+   As I don't know well Unix, I wait feedback for the unix portion */
+
+int mymkdir(dirname)
+    const char* dirname;
+{
+    int ret=0;
+#ifdef WIN32
+    ret = mkdir(dirname);
+#else
+#ifdef unix
+    ret = mkdir (dirname,0775);
+#endif
+#endif
+    return ret;
+}
+
+int makedir (newdir)
+    char *newdir;
+{
+  char *buffer ;
+  char *p;
+  int  len = (int)strlen(newdir);
+
+  if (len <= 0)
+    return 0;
+
+  buffer = (char*)malloc(len+1);
+  strcpy(buffer,newdir);
+
+  if (buffer[len-1] == '/') {
+    buffer[len-1] = '\0';
+  }
+  if (mymkdir(buffer) == 0)
+    {
+      free(buffer);
+      return 1;
+    }
+
+  p = buffer+1;
+  while (1)
+    {
+      char hold;
+
+      while(*p && *p != '\\' && *p != '/')
+        p++;
+      hold = *p;
+      *p = 0;
+      if ((mymkdir(buffer) == -1) && (errno == ENOENT))
+        {
+          printf("couldn't create directory %s\n",buffer);
+          free(buffer);
+          return 0;
+        }
+      if (hold == 0)
+        break;
+      *p++ = hold;
+    }
+  free(buffer);
+  return 1;
+}
+
+void do_banner()
+{
+    printf("MiniUnz 1.01b, demo of zLib + Unz package written by Gilles Vollant\n");
+    printf("more info at http://www.winimage.com/zLibDll/unzip.html\n\n");
+}
+
+void do_help()
+{
+    printf("Usage : miniunz [-e] [-x] [-v] [-l] [-o] [-p password] file.zip [file_to_extr.] [-d extractdir]\n\n" \
+           "  -e  Extract without pathname (junk paths)\n" \
+           "  -x  Extract with pathname\n" \
+           "  -v  list files\n" \
+           "  -l  list files\n" \
+           "  -d  directory to extract into\n" \
+           "  -o  overwrite files without prompting\n" \
+           "  -p  extract crypted file using password\n\n");
+}
+
+
+int do_list(uf)
+    unzFile uf;
+{
+    uLong i;
+    unz_global_info gi;
+    int err;
+
+    err = unzGetGlobalInfo (uf,&gi);
+    if (err!=UNZ_OK)
+        printf("error %d with zipfile in unzGetGlobalInfo \n",err);
+    printf(" Length  Method   Size  Ratio   Date    Time   CRC-32     Name\n");
+    printf(" ------  ------   ----  -----   ----    ----   ------     ----\n");
+    for (i=0;i<gi.number_entry;i++)
+    {
+        char filename_inzip[256];
+        unz_file_info file_info;
+        uLong ratio=0;
+        const char *string_method;
+        char charCrypt=' ';
+        err = unzGetCurrentFileInfo(uf,&file_info,filename_inzip,sizeof(filename_inzip),NULL,0,NULL,0);
+        if (err!=UNZ_OK)
+        {
+            printf("error %d with zipfile in unzGetCurrentFileInfo\n",err);
+            break;
+        }
+        if (file_info.uncompressed_size>0)
+            ratio = (file_info.compressed_size*100)/file_info.uncompressed_size;
+
+        /* display a '*' if the file is crypted */
+        if ((file_info.flag & 1) != 0)
+            charCrypt='*';
+
+        if (file_info.compression_method==0)
+            string_method="Stored";
+        else
+        if (file_info.compression_method==Z_DEFLATED)
+        {
+            uInt iLevel=(uInt)((file_info.flag & 0x6)/2);
+            if (iLevel==0)
+              string_method="Defl:N";
+            else if (iLevel==1)
+              string_method="Defl:X";
+            else if ((iLevel==2) || (iLevel==3))
+              string_method="Defl:F"; /* 2:fast , 3 : extra fast*/
+        }
+        else
+            string_method="Unkn. ";
+
+        printf("%7lu  %6s%c%7lu %3lu%%  %2.2lu-%2.2lu-%2.2lu  %2.2lu:%2.2lu  %8.8lx   %s\n",
+                file_info.uncompressed_size,string_method,
+                charCrypt,
+                file_info.compressed_size,
+                ratio,
+                (uLong)file_info.tmu_date.tm_mon + 1,
+                (uLong)file_info.tmu_date.tm_mday,
+                (uLong)file_info.tmu_date.tm_year % 100,
+                (uLong)file_info.tmu_date.tm_hour,(uLong)file_info.tmu_date.tm_min,
+                (uLong)file_info.crc,filename_inzip);
+        if ((i+1)<gi.number_entry)
+        {
+            err = unzGoToNextFile(uf);
+            if (err!=UNZ_OK)
+            {
+                printf("error %d with zipfile in unzGoToNextFile\n",err);
+                break;
+            }
+        }
+    }
+
+    return 0;
+}
+
+
+int do_extract_currentfile(uf,popt_extract_without_path,popt_overwrite,password)
+    unzFile uf;
+    const int* popt_extract_without_path;
+    int* popt_overwrite;
+    const char* password;
+{
+    char filename_inzip[256];
+    char* filename_withoutpath;
+    char* p;
+    int err=UNZ_OK;
+    FILE *fout=NULL;
+    void* buf;
+    uInt size_buf;
+
+    unz_file_info file_info;
+    uLong ratio=0;
+    err = unzGetCurrentFileInfo(uf,&file_info,filename_inzip,sizeof(filename_inzip),NULL,0,NULL,0);
+
+    if (err!=UNZ_OK)
+    {
+        printf("error %d with zipfile in unzGetCurrentFileInfo\n",err);
+        return err;
+    }
+
+    size_buf = WRITEBUFFERSIZE;
+    buf = (void*)malloc(size_buf);
+    if (buf==NULL)
+    {
+        printf("Error allocating memory\n");
+        return UNZ_INTERNALERROR;
+    }
+
+    p = filename_withoutpath = filename_inzip;
+    while ((*p) != '\0')
+    {
+        if (((*p)=='/') || ((*p)=='\\'))
+            filename_withoutpath = p+1;
+        p++;
+    }
+
+    if ((*filename_withoutpath)=='\0')
+    {
+        if ((*popt_extract_without_path)==0)
+        {
+            printf("creating directory: %s\n",filename_inzip);
+            mymkdir(filename_inzip);
+        }
+    }
+    else
+    {
+        const char* write_filename;
+        int skip=0;
+
+        if ((*popt_extract_without_path)==0)
+            write_filename = filename_inzip;
+        else
+            write_filename = filename_withoutpath;
+
+        err = unzOpenCurrentFilePassword(uf,password);
+        if (err!=UNZ_OK)
+        {
+            printf("error %d with zipfile in unzOpenCurrentFilePassword\n",err);
+        }
+
+        if (((*popt_overwrite)==0) && (err==UNZ_OK))
+        {
+            char rep=0;
+            FILE* ftestexist;
+            ftestexist = fopen(write_filename,"rb");
+            if (ftestexist!=NULL)
+            {
+                fclose(ftestexist);
+                do
+                {
+                    char answer[128];
+                    int ret;
+
+                    printf("The file %s exists. Overwrite ? [y]es, [n]o, [A]ll: ",write_filename);
+                    ret = scanf("%1s",answer);
+                    if (ret != 1) 
+                    {
+                       exit(EXIT_FAILURE);
+                    }
+                    rep = answer[0] ;
+                    if ((rep>='a') && (rep<='z'))
+                        rep -= 0x20;
+                }
+                while ((rep!='Y') && (rep!='N') && (rep!='A'));
+            }
+
+            if (rep == 'N')
+                skip = 1;
+
+            if (rep == 'A')
+                *popt_overwrite=1;
+        }
+
+        if ((skip==0) && (err==UNZ_OK))
+        {
+            fout=fopen(write_filename,"wb");
+
+            /* some zipfile don't contain directory alone before file */
+            if ((fout==NULL) && ((*popt_extract_without_path)==0) &&
+                                (filename_withoutpath!=(char*)filename_inzip))
+            {
+                char c=*(filename_withoutpath-1);
+                *(filename_withoutpath-1)='\0';
+                makedir(write_filename);
+                *(filename_withoutpath-1)=c;
+                fout=fopen(write_filename,"wb");
+            }
+
+            if (fout==NULL)
+            {
+                printf("error opening %s\n",write_filename);
+            }
+        }
+
+        if (fout!=NULL)
+        {
+            printf(" extracting: %s\n",write_filename);
+
+            do
+            {
+                err = unzReadCurrentFile(uf,buf,size_buf);
+                if (err<0)
+                {
+                    printf("error %d with zipfile in unzReadCurrentFile\n",err);
+                    break;
+                }
+                if (err>0)
+                    if (fwrite(buf,err,1,fout)!=1)
+                    {
+                        printf("error in writing extracted file\n");
+                        err=UNZ_ERRNO;
+                        break;
+                    }
+            }
+            while (err>0);
+            if (fout)
+                    fclose(fout);
+
+            if (err==0)
+                change_file_date(write_filename,file_info.dosDate,
+                                 file_info.tmu_date);
+        }
+
+        if (err==UNZ_OK)
+        {
+            err = unzCloseCurrentFile (uf);
+            if (err!=UNZ_OK)
+            {
+                printf("error %d with zipfile in unzCloseCurrentFile\n",err);
+            }
+        }
+        else
+            unzCloseCurrentFile(uf); /* don't lose the error */
+    }
+
+    free(buf);
+    return err;
+}
+
+
+int do_extract(uf,opt_extract_without_path,opt_overwrite,password)
+    unzFile uf;
+    int opt_extract_without_path;
+    int opt_overwrite;
+    const char* password;
+{
+    uLong i;
+    unz_global_info gi;
+    int err;
+    FILE* fout=NULL;
+
+    err = unzGetGlobalInfo (uf,&gi);
+    if (err!=UNZ_OK)
+        printf("error %d with zipfile in unzGetGlobalInfo \n",err);
+
+    for (i=0;i<gi.number_entry;i++)
+    {
+        if (do_extract_currentfile(uf,&opt_extract_without_path,
+                                      &opt_overwrite,
+                                      password) != UNZ_OK)
+            break;
+
+        if ((i+1)<gi.number_entry)
+        {
+            err = unzGoToNextFile(uf);
+            if (err!=UNZ_OK)
+            {
+                printf("error %d with zipfile in unzGoToNextFile\n",err);
+                break;
+            }
+        }
+    }
+
+    return 0;
+}
+
+int do_extract_onefile(uf,filename,opt_extract_without_path,opt_overwrite,password)
+    unzFile uf;
+    const char* filename;
+    int opt_extract_without_path;
+    int opt_overwrite;
+    const char* password;
+{
+    int err = UNZ_OK;
+    if (unzLocateFile(uf,filename,CASESENSITIVITY)!=UNZ_OK)
+    {
+        printf("file %s not found in the zipfile\n",filename);
+        return 2;
+    }
+
+    if (do_extract_currentfile(uf,&opt_extract_without_path,
+                                      &opt_overwrite,
+                                      password) == UNZ_OK)
+        return 0;
+    else
+        return 1;
+}
+
+
+int main(argc,argv)
+    int argc;
+    char *argv[];
+{
+    const char *zipfilename=NULL;
+    const char *filename_to_extract=NULL;
+    const char *password=NULL;
+    char filename_try[MAXFILENAME+16] = "";
+    int i;
+    int opt_do_list=0;
+    int opt_do_extract=1;
+    int opt_do_extract_withoutpath=0;
+    int opt_overwrite=0;
+    int opt_extractdir=0;
+    const char *dirname=NULL;
+    unzFile uf=NULL;
+
+    do_banner();
+    if (argc==1)
+    {
+        do_help();
+        return 0;
+    }
+    else
+    {
+        for (i=1;i<argc;i++)
+        {
+            if ((*argv[i])=='-')
+            {
+                const char *p=argv[i]+1;
+
+                while ((*p)!='\0')
+                {
+                    char c=*(p++);;
+                    if ((c=='l') || (c=='L'))
+                        opt_do_list = 1;
+                    if ((c=='v') || (c=='V'))
+                        opt_do_list = 1;
+                    if ((c=='x') || (c=='X'))
+                        opt_do_extract = 1;
+                    if ((c=='e') || (c=='E'))
+                        opt_do_extract = opt_do_extract_withoutpath = 1;
+                    if ((c=='o') || (c=='O'))
+                        opt_overwrite=1;
+                    if ((c=='d') || (c=='D'))
+                    {
+                        opt_extractdir=1;
+                        dirname=argv[i+1];
+                    }
+
+                    if (((c=='p') || (c=='P')) && (i+1<argc))
+                    {
+                        password=argv[i+1];
+                        i++;
+                    }
+                }
+            }
+            else
+            {
+                if (zipfilename == NULL)
+                    zipfilename = argv[i];
+                else if ((filename_to_extract==NULL) && (!opt_extractdir))
+                        filename_to_extract = argv[i] ;
+            }
+        }
+    }
+
+    if (zipfilename!=NULL)
+    {
+
+#        ifdef USEWIN32IOAPI
+        zlib_filefunc_def ffunc;
+#        endif
+
+        strncpy(filename_try, zipfilename,MAXFILENAME-1);
+        /* strncpy doesnt append the trailing NULL, of the string is too long. */
+        filename_try[ MAXFILENAME ] = '\0';
+
+#        ifdef USEWIN32IOAPI
+        fill_win32_filefunc(&ffunc);
+        uf = unzOpen2(zipfilename,&ffunc);
+#        else
+        uf = unzOpen(zipfilename);
+#        endif
+        if (uf==NULL)
+        {
+            strcat(filename_try,".zip");
+#            ifdef USEWIN32IOAPI
+            uf = unzOpen2(filename_try,&ffunc);
+#            else
+            uf = unzOpen(filename_try);
+#            endif
+        }
+    }
+
+    if (uf==NULL)
+    {
+        printf("Cannot open %s or %s.zip\n",zipfilename,zipfilename);
+        return 1;
+    }
+    printf("%s opened\n",filename_try);
+
+    if (opt_do_list==1)
+        return do_list(uf);
+    else if (opt_do_extract==1)
+    {
+        if (opt_extractdir && chdir(dirname)) 
+        {
+          printf("Error changing into %s, aborting\n", dirname);
+          exit(-1);
+        }
+
+        if (filename_to_extract == NULL)
+            return do_extract(uf,opt_do_extract_withoutpath,opt_overwrite,password);
+        else
+            return do_extract_onefile(uf,filename_to_extract,
+                                      opt_do_extract_withoutpath,opt_overwrite,password);
+    }
+    unzCloseCurrentFile(uf);
+
+    return 0;
+}
diff --git a/gs/zlib/contrib/minizip/minizip.c b/gs/zlib/contrib/minizip/minizip.c
new file mode 100644
index 000000000..f2dfecd8b
--- /dev/null
+++ b/gs/zlib/contrib/minizip/minizip.c
@@ -0,0 +1,420 @@
+/*
+   minizip.c
+   Version 1.01e, February 12th, 2005
+
+   Copyright (C) 1998-2005 Gilles Vollant
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <errno.h>
+#include <fcntl.h>
+
+#ifdef unix
+# include <unistd.h>
+# include <utime.h>
+# include <sys/types.h>
+# include <sys/stat.h>
+#else
+# include <direct.h>
+# include <io.h>
+#endif
+
+#include "zip.h"
+
+#ifdef WIN32
+#define USEWIN32IOAPI
+#include "iowin32.h"
+#endif
+
+
+
+#define WRITEBUFFERSIZE (16384)
+#define MAXFILENAME (256)
+
+#ifdef WIN32
+uLong filetime(f, tmzip, dt)
+    char *f;                /* name of file to get info on */
+    tm_zip *tmzip;             /* return value: access, modific. and creation times */
+    uLong *dt;             /* dostime */
+{
+  int ret = 0;
+  {
+      FILETIME ftLocal;
+      HANDLE hFind;
+      WIN32_FIND_DATA  ff32;
+
+      hFind = FindFirstFile(f,&ff32);
+      if (hFind != INVALID_HANDLE_VALUE)
+      {
+        FileTimeToLocalFileTime(&(ff32.ftLastWriteTime),&ftLocal);
+        FileTimeToDosDateTime(&ftLocal,((LPWORD)dt)+1,((LPWORD)dt)+0);
+        FindClose(hFind);
+        ret = 1;
+      }
+  }
+  return ret;
+}
+#else
+#ifdef unix
+uLong filetime(f, tmzip, dt)
+    char *f;               /* name of file to get info on */
+    tm_zip *tmzip;         /* return value: access, modific. and creation times */
+    uLong *dt;             /* dostime */
+{
+  int ret=0;
+  struct stat s;        /* results of stat() */
+  struct tm* filedate;
+  time_t tm_t=0;
+
+  if (strcmp(f,"-")!=0)
+  {
+    char name[MAXFILENAME+1];
+    int len = strlen(f);
+    if (len > MAXFILENAME)
+      len = MAXFILENAME;
+
+    strncpy(name, f,MAXFILENAME-1);
+    /* strncpy doesnt append the trailing NULL, of the string is too long. */
+    name[ MAXFILENAME ] = '\0';
+
+    if (name[len - 1] == '/')
+      name[len - 1] = '\0';
+    /* not all systems allow stat'ing a file with / appended */
+    if (stat(name,&s)==0)
+    {
+      tm_t = s.st_mtime;
+      ret = 1;
+    }
+  }
+  filedate = localtime(&tm_t);
+
+  tmzip->tm_sec  = filedate->tm_sec;
+  tmzip->tm_min  = filedate->tm_min;
+  tmzip->tm_hour = filedate->tm_hour;
+  tmzip->tm_mday = filedate->tm_mday;
+  tmzip->tm_mon  = filedate->tm_mon ;
+  tmzip->tm_year = filedate->tm_year;
+
+  return ret;
+}
+#else
+uLong filetime(f, tmzip, dt)
+    char *f;                /* name of file to get info on */
+    tm_zip *tmzip;             /* return value: access, modific. and creation times */
+    uLong *dt;             /* dostime */
+{
+    return 0;
+}
+#endif
+#endif
+
+
+
+
+int check_exist_file(filename)
+    const char* filename;
+{
+    FILE* ftestexist;
+    int ret = 1;
+    ftestexist = fopen(filename,"rb");
+    if (ftestexist==NULL)
+        ret = 0;
+    else
+        fclose(ftestexist);
+    return ret;
+}
+
+void do_banner()
+{
+    printf("MiniZip 1.01b, demo of zLib + Zip package written by Gilles Vollant\n");
+    printf("more info at http://www.winimage.com/zLibDll/unzip.html\n\n");
+}
+
+void do_help()
+{
+    printf("Usage : minizip [-o] [-a] [-0 to -9] [-p password] file.zip [files_to_add]\n\n" \
+           "  -o  Overwrite existing file.zip\n" \
+           "  -a  Append to existing file.zip\n" \
+           "  -0  Store only\n" \
+           "  -1  Compress faster\n" \
+           "  -9  Compress better\n\n");
+}
+
+/* calculate the CRC32 of a file,
+   because to encrypt a file, we need known the CRC32 of the file before */
+int getFileCrc(const char* filenameinzip,void*buf,unsigned long size_buf,unsigned long* result_crc)
+{
+   unsigned long calculate_crc=0;
+   int err=ZIP_OK;
+   FILE * fin = fopen(filenameinzip,"rb");
+   unsigned long size_read = 0;
+   unsigned long total_read = 0;
+   if (fin==NULL)
+   {
+       err = ZIP_ERRNO;
+   }
+
+    if (err == ZIP_OK)
+        do
+        {
+            err = ZIP_OK;
+            size_read = (int)fread(buf,1,size_buf,fin);
+            if (size_read < size_buf)
+                if (feof(fin)==0)
+            {
+                printf("error in reading %s\n",filenameinzip);
+                err = ZIP_ERRNO;
+            }
+
+            if (size_read>0)
+                calculate_crc = crc32(calculate_crc,buf,size_read);
+            total_read += size_read;
+
+        } while ((err == ZIP_OK) && (size_read>0));
+
+    if (fin)
+        fclose(fin);
+
+    *result_crc=calculate_crc;
+    printf("file %s crc %x\n",filenameinzip,calculate_crc);
+    return err;
+}
+
+int main(argc,argv)
+    int argc;
+    char *argv[];
+{
+    int i;
+    int opt_overwrite=0;
+    int opt_compress_level=Z_DEFAULT_COMPRESSION;
+    int zipfilenamearg = 0;
+    char filename_try[MAXFILENAME+16];
+    int zipok;
+    int err=0;
+    int size_buf=0;
+    void* buf=NULL;
+    const char* password=NULL;
+
+
+    do_banner();
+    if (argc==1)
+    {
+        do_help();
+        return 0;
+    }
+    else
+    {
+        for (i=1;i<argc;i++)
+        {
+            if ((*argv[i])=='-')
+            {
+                const char *p=argv[i]+1;
+
+                while ((*p)!='\0')
+                {
+                    char c=*(p++);;
+                    if ((c=='o') || (c=='O'))
+                        opt_overwrite = 1;
+                    if ((c=='a') || (c=='A'))
+                        opt_overwrite = 2;
+                    if ((c>='0') && (c<='9'))
+                        opt_compress_level = c-'0';
+
+                    if (((c=='p') || (c=='P')) && (i+1<argc))
+                    {
+                        password=argv[i+1];
+                        i++;
+                    }
+                }
+            }
+            else
+                if (zipfilenamearg == 0)
+                    zipfilenamearg = i ;
+        }
+    }
+
+    size_buf = WRITEBUFFERSIZE;
+    buf = (void*)malloc(size_buf);
+    if (buf==NULL)
+    {
+        printf("Error allocating memory\n");
+        return ZIP_INTERNALERROR;
+    }
+
+    if (zipfilenamearg==0)
+        zipok=0;
+    else
+    {
+        int i,len;
+        int dot_found=0;
+
+        zipok = 1 ;
+        strncpy(filename_try, argv[zipfilenamearg],MAXFILENAME-1);
+        /* strncpy doesnt append the trailing NULL, of the string is too long. */
+        filename_try[ MAXFILENAME ] = '\0';
+
+        len=(int)strlen(filename_try);
+        for (i=0;i<len;i++)
+            if (filename_try[i]=='.')
+                dot_found=1;
+
+        if (dot_found==0)
+            strcat(filename_try,".zip");
+
+        if (opt_overwrite==2)
+        {
+            /* if the file don't exist, we not append file */
+            if (check_exist_file(filename_try)==0)
+                opt_overwrite=1;
+        }
+        else
+        if (opt_overwrite==0)
+            if (check_exist_file(filename_try)!=0)
+            {
+                char rep=0;
+                do
+                {
+                    char answer[128];
+                    int ret;
+                    printf("The file %s exists. Overwrite ? [y]es, [n]o, [a]ppend : ",filename_try);
+                    ret = scanf("%1s",answer);
+                    if (ret != 1)
+                    {
+                       exit(EXIT_FAILURE);
+                    }
+                    rep = answer[0] ;
+                    if ((rep>='a') && (rep<='z'))
+                        rep -= 0x20;
+                }
+                while ((rep!='Y') && (rep!='N') && (rep!='A'));
+                if (rep=='N')
+                    zipok = 0;
+                if (rep=='A')
+                    opt_overwrite = 2;
+            }
+    }
+
+    if (zipok==1)
+    {
+        zipFile zf;
+        int errclose;
+#        ifdef USEWIN32IOAPI
+        zlib_filefunc_def ffunc;
+        fill_win32_filefunc(&ffunc);
+        zf = zipOpen2(filename_try,(opt_overwrite==2) ? 2 : 0,NULL,&ffunc);
+#        else
+        zf = zipOpen(filename_try,(opt_overwrite==2) ? 2 : 0);
+#        endif
+
+        if (zf == NULL)
+        {
+            printf("error opening %s\n",filename_try);
+            err= ZIP_ERRNO;
+        }
+        else
+            printf("creating %s\n",filename_try);
+
+        for (i=zipfilenamearg+1;(i<argc) && (err==ZIP_OK);i++)
+        {
+            if (!((((*(argv[i]))=='-') || ((*(argv[i]))=='/')) &&
+                  ((argv[i][1]=='o') || (argv[i][1]=='O') ||
+                   (argv[i][1]=='a') || (argv[i][1]=='A') ||
+                   (argv[i][1]=='p') || (argv[i][1]=='P') ||
+                   ((argv[i][1]>='0') || (argv[i][1]<='9'))) &&
+                  (strlen(argv[i]) == 2)))
+            {
+                FILE * fin;
+                int size_read;
+                const char* filenameinzip = argv[i];
+                zip_fileinfo zi;
+                unsigned long crcFile=0;
+
+                zi.tmz_date.tm_sec = zi.tmz_date.tm_min = zi.tmz_date.tm_hour =
+                zi.tmz_date.tm_mday = zi.tmz_date.tm_mon = zi.tmz_date.tm_year = 0;
+                zi.dosDate = 0;
+                zi.internal_fa = 0;
+                zi.external_fa = 0;
+                filetime(filenameinzip,&zi.tmz_date,&zi.dosDate);
+
+/*
+                err = zipOpenNewFileInZip(zf,filenameinzip,&zi,
+                                 NULL,0,NULL,0,NULL / * comment * /,
+                                 (opt_compress_level != 0) ? Z_DEFLATED : 0,
+                                 opt_compress_level);
+*/
+                if ((password != NULL) && (err==ZIP_OK))
+                    err = getFileCrc(filenameinzip,buf,size_buf,&crcFile);
+
+                err = zipOpenNewFileInZip3(zf,filenameinzip,&zi,
+                                 NULL,0,NULL,0,NULL /* comment*/,
+                                 (opt_compress_level != 0) ? Z_DEFLATED : 0,
+                                 opt_compress_level,0,
+                                 /* -MAX_WBITS, DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY, */
+                                 -MAX_WBITS, DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY,
+                                 password,crcFile);
+
+                if (err != ZIP_OK)
+                    printf("error in opening %s in zipfile\n",filenameinzip);
+                else
+                {
+                    fin = fopen(filenameinzip,"rb");
+                    if (fin==NULL)
+                    {
+                        err=ZIP_ERRNO;
+                        printf("error in opening %s for reading\n",filenameinzip);
+                    }
+                }
+
+                if (err == ZIP_OK)
+                    do
+                    {
+                        err = ZIP_OK;
+                        size_read = (int)fread(buf,1,size_buf,fin);
+                        if (size_read < size_buf)
+                            if (feof(fin)==0)
+                        {
+                            printf("error in reading %s\n",filenameinzip);
+                            err = ZIP_ERRNO;
+                        }
+
+                        if (size_read>0)
+                        {
+                            err = zipWriteInFileInZip (zf,buf,size_read);
+                            if (err<0)
+                            {
+                                printf("error in writing %s in the zipfile\n",
+                                                 filenameinzip);
+                            }
+
+                        }
+                    } while ((err == ZIP_OK) && (size_read>0));
+
+                if (fin)
+                    fclose(fin);
+
+                if (err<0)
+                    err=ZIP_ERRNO;
+                else
+                {
+                    err = zipCloseFileInZip(zf);
+                    if (err!=ZIP_OK)
+                        printf("error in closing %s in the zipfile\n",
+                                    filenameinzip);
+                }
+            }
+        }
+        errclose = zipClose(zf,NULL);
+        if (errclose != ZIP_OK)
+            printf("error in closing %s\n",filename_try);
+    }
+    else
+    {
+       do_help();
+    }
+
+    free(buf);
+    return 0;
+}
diff --git a/gs/zlib/contrib/minizip/mztools.c b/gs/zlib/contrib/minizip/mztools.c
new file mode 100644
index 000000000..8a50ee439
--- /dev/null
+++ b/gs/zlib/contrib/minizip/mztools.c
@@ -0,0 +1,281 @@
+/*
+  Additional tools for Minizip
+  Code: Xavier Roche '2004
+  License: Same as ZLIB (www.gzip.org)
+*/
+
+/* Code */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "zlib.h"
+#include "unzip.h"
+
+#define READ_8(adr)  ((unsigned char)*(adr))
+#define READ_16(adr) ( READ_8(adr) | (READ_8(adr+1) << 8) )
+#define READ_32(adr) ( READ_16(adr) | (READ_16((adr)+2) << 16) )
+
+#define WRITE_8(buff, n) do { \
+  *((unsigned char*)(buff)) = (unsigned char) ((n) & 0xff); \
+} while(0)
+#define WRITE_16(buff, n) do { \
+  WRITE_8((unsigned char*)(buff), n); \
+  WRITE_8(((unsigned char*)(buff)) + 1, (n) >> 8); \
+} while(0)
+#define WRITE_32(buff, n) do { \
+  WRITE_16((unsigned char*)(buff), (n) & 0xffff); \
+  WRITE_16((unsigned char*)(buff) + 2, (n) >> 16); \
+} while(0)
+
+extern int ZEXPORT unzRepair(file, fileOut, fileOutTmp, nRecovered, bytesRecovered)
+const char* file;
+const char* fileOut;
+const char* fileOutTmp;
+uLong* nRecovered;
+uLong* bytesRecovered;
+{
+  int err = Z_OK;
+  FILE* fpZip = fopen(file, "rb");
+  FILE* fpOut = fopen(fileOut, "wb");
+  FILE* fpOutCD = fopen(fileOutTmp, "wb");
+  if (fpZip != NULL &&  fpOut != NULL) {
+    int entries = 0;
+    uLong totalBytes = 0;
+    char header[30];
+    char filename[256];
+    char extra[1024];
+    int offset = 0;
+    int offsetCD = 0;
+    while ( fread(header, 1, 30, fpZip) == 30 ) {
+      int currentOffset = offset;
+
+      /* File entry */
+      if (READ_32(header) == 0x04034b50) {
+        unsigned int version = READ_16(header + 4);
+        unsigned int gpflag = READ_16(header + 6);
+        unsigned int method = READ_16(header + 8);
+        unsigned int filetime = READ_16(header + 10);
+        unsigned int filedate = READ_16(header + 12);
+        unsigned int crc = READ_32(header + 14); /* crc */
+        unsigned int cpsize = READ_32(header + 18); /* compressed size */
+        unsigned int uncpsize = READ_32(header + 22); /* uncompressed sz */
+        unsigned int fnsize = READ_16(header + 26); /* file name length */
+        unsigned int extsize = READ_16(header + 28); /* extra field length */
+        filename[0] = extra[0] = '\0';
+        
+        /* Header */
+        if (fwrite(header, 1, 30, fpOut) == 30) {
+          offset += 30;
+        } else {
+          err = Z_ERRNO;
+          break;
+        }
+        
+        /* Filename */
+        if (fnsize > 0) {
+          if (fread(filename, 1, fnsize, fpZip) == fnsize) {
+            if (fwrite(filename, 1, fnsize, fpOut) == fnsize) {
+              offset += fnsize;
+            } else {
+              err = Z_ERRNO;
+              break;
+            }
+          } else {
+            err = Z_ERRNO;
+            break;
+          }
+        } else {
+          err = Z_STREAM_ERROR;
+          break;
+        }
+
+        /* Extra field */
+        if (extsize > 0) {
+          if (fread(extra, 1, extsize, fpZip) == extsize) {
+            if (fwrite(extra, 1, extsize, fpOut) == extsize) {
+              offset += extsize;
+            } else {
+              err = Z_ERRNO;
+              break;
+            }
+          } else {
+            err = Z_ERRNO;
+            break;
+          }
+        }
+        
+        /* Data */
+        {
+          int dataSize = cpsize;
+          if (dataSize == 0) {
+            dataSize = uncpsize;
+          }
+          if (dataSize > 0) {
+            char* data = malloc(dataSize);
+            if (data != NULL) {
+              if ((int)fread(data, 1, dataSize, fpZip) == dataSize) {
+                if ((int)fwrite(data, 1, dataSize, fpOut) == dataSize) {
+                  offset += dataSize;
+                  totalBytes += dataSize;
+                } else {
+                  err = Z_ERRNO;
+                }
+              } else {
+                err = Z_ERRNO;
+              }
+              free(data);
+              if (err != Z_OK) {
+                break;
+              }
+            } else {
+              err = Z_MEM_ERROR;
+              break;
+            }
+          }
+        }
+        
+        /* Central directory entry */
+        {
+          char header[46];
+          char* comment = "";
+          int comsize = (int) strlen(comment);
+          WRITE_32(header, 0x02014b50);
+          WRITE_16(header + 4, version);
+          WRITE_16(header + 6, version);
+          WRITE_16(header + 8, gpflag);
+          WRITE_16(header + 10, method);
+          WRITE_16(header + 12, filetime);
+          WRITE_16(header + 14, filedate);
+          WRITE_32(header + 16, crc);
+          WRITE_32(header + 20, cpsize);
+          WRITE_32(header + 24, uncpsize);
+          WRITE_16(header + 28, fnsize);
+          WRITE_16(header + 30, extsize);
+          WRITE_16(header + 32, comsize);
+          WRITE_16(header + 34, 0);     /* disk # */
+          WRITE_16(header + 36, 0);     /* int attrb */
+          WRITE_32(header + 38, 0);     /* ext attrb */
+          WRITE_32(header + 42, currentOffset);
+          /* Header */
+          if (fwrite(header, 1, 46, fpOutCD) == 46) {
+            offsetCD += 46;
+            
+            /* Filename */
+            if (fnsize > 0) {
+              if (fwrite(filename, 1, fnsize, fpOutCD) == fnsize) {
+                offsetCD += fnsize;
+              } else {
+                err = Z_ERRNO;
+                break;
+              }
+            } else {
+              err = Z_STREAM_ERROR;
+              break;
+            }
+            
+            /* Extra field */
+            if (extsize > 0) {
+              if (fwrite(extra, 1, extsize, fpOutCD) == extsize) {
+                offsetCD += extsize;
+              } else {
+                err = Z_ERRNO;
+                break;
+              }
+            }
+            
+            /* Comment field */
+            if (comsize > 0) {
+              if ((int)fwrite(comment, 1, comsize, fpOutCD) == comsize) {
+                offsetCD += comsize;
+              } else {
+                err = Z_ERRNO;
+                break;
+              }
+            }
+            
+            
+          } else {
+            err = Z_ERRNO;
+            break;
+          }
+        }
+
+        /* Success */
+        entries++;
+
+      } else {
+        break;
+      }
+    }
+
+    /* Final central directory  */
+    {
+      int entriesZip = entries;
+      char header[22];
+      char* comment = ""; // "ZIP File recovered by zlib/minizip/mztools";
+      int comsize = (int) strlen(comment);
+      if (entriesZip > 0xffff) {
+        entriesZip = 0xffff;
+      }
+      WRITE_32(header, 0x06054b50);
+      WRITE_16(header + 4, 0);    /* disk # */
+      WRITE_16(header + 6, 0);    /* disk # */
+      WRITE_16(header + 8, entriesZip);   /* hack */
+      WRITE_16(header + 10, entriesZip);  /* hack */
+      WRITE_32(header + 12, offsetCD);    /* size of CD */
+      WRITE_32(header + 16, offset);      /* offset to CD */
+      WRITE_16(header + 20, comsize);     /* comment */
+      
+      /* Header */
+      if (fwrite(header, 1, 22, fpOutCD) == 22) {
+        
+        /* Comment field */
+        if (comsize > 0) {
+          if ((int)fwrite(comment, 1, comsize, fpOutCD) != comsize) {
+            err = Z_ERRNO;
+          }
+        }
+        
+      } else {
+        err = Z_ERRNO;
+      }
+    }
+
+    /* Final merge (file + central directory) */
+    fclose(fpOutCD);
+    if (err == Z_OK) {
+      fpOutCD = fopen(fileOutTmp, "rb");
+      if (fpOutCD != NULL) {
+        int nRead;
+        char buffer[8192];
+        while ( (nRead = (int)fread(buffer, 1, sizeof(buffer), fpOutCD)) > 0) {
+          if ((int)fwrite(buffer, 1, nRead, fpOut) != nRead) {
+            err = Z_ERRNO;
+            break;
+          }
+        }
+        fclose(fpOutCD);
+      }
+    }
+    
+    /* Close */
+    fclose(fpZip);
+    fclose(fpOut);
+    
+    /* Wipe temporary file */
+    (void)remove(fileOutTmp);
+    
+    /* Number of recovered entries */
+    if (err == Z_OK) {
+      if (nRecovered != NULL) {
+        *nRecovered = entries;
+      }
+      if (bytesRecovered != NULL) {
+        *bytesRecovered = totalBytes;
+      }
+    }
+  } else {
+    err = Z_STREAM_ERROR;
+  }
+  return err;
+}
diff --git a/gs/zlib/contrib/minizip/mztools.h b/gs/zlib/contrib/minizip/mztools.h
new file mode 100644
index 000000000..eee78dc56
--- /dev/null
+++ b/gs/zlib/contrib/minizip/mztools.h
@@ -0,0 +1,31 @@
+/*
+  Additional tools for Minizip
+  Code: Xavier Roche '2004
+  License: Same as ZLIB (www.gzip.org)
+*/
+
+#ifndef _zip_tools_H
+#define _zip_tools_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef _ZLIB_H
+#include "zlib.h"
+#endif
+
+#include "unzip.h"
+
+/* Repair a ZIP file (missing central directory) 
+   file: file to recover
+   fileOut: output file after recovery
+   fileOutTmp: temporary file name used for recovery
+*/
+extern int ZEXPORT unzRepair(const char* file, 
+                             const char* fileOut, 
+                             const char* fileOutTmp, 
+                             uLong* nRecovered,
+                             uLong* bytesRecovered);
+
+#endif
diff --git a/gs/zlib/contrib/minizip/unzip.c b/gs/zlib/contrib/minizip/unzip.c
new file mode 100644
index 000000000..9ad4766d8
--- /dev/null
+++ b/gs/zlib/contrib/minizip/unzip.c
@@ -0,0 +1,1598 @@
+/* unzip.c -- IO for uncompress .zip files using zlib
+   Version 1.01e, February 12th, 2005
+
+   Copyright (C) 1998-2005 Gilles Vollant
+
+   Read unzip.h for more info
+*/
+
+/* Decryption code comes from crypt.c by Info-ZIP but has been greatly reduced in terms of
+compatibility with older software. The following is from the original crypt.c. Code
+woven in by Terry Thorsen 1/2003.
+*/
+/*
+  Copyright (c) 1990-2000 Info-ZIP.  All rights reserved.
+
+  See the accompanying file LICENSE, version 2000-Apr-09 or later
+  (the contents of which are also included in zip.h) for terms of use.
+  If, for some reason, all these files are missing, the Info-ZIP license
+  also may be found at:  ftp://ftp.info-zip.org/pub/infozip/license.html
+*/
+/*
+  crypt.c (full version) by Info-ZIP.      Last revised:  [see crypt.h]
+
+  The encryption/decryption parts of this source code (as opposed to the
+  non-echoing password parts) were originally written in Europe.  The
+  whole source package can be freely distributed, including from the USA.
+  (Prior to January 2000, re-export from the US was a violation of US law.)
+ */
+
+/*
+  This encryption code is a direct transcription of the algorithm from
+  Roger Schlafly, described by Phil Katz in the file appnote.txt.  This
+  file (appnote.txt) is distributed with the PKZIP program (even in the
+  version without encryption capabilities).
+ */
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "zlib.h"
+#include "unzip.h"
+
+#ifdef STDC
+#  include <stddef.h>
+#  include <string.h>
+#  include <stdlib.h>
+#endif
+#ifdef NO_ERRNO_H
+    extern int errno;
+#else
+#   include <errno.h>
+#endif
+
+
+#ifndef local
+#  define local static
+#endif
+/* compile with -Dlocal if your debugger can't find static symbols */
+
+
+#ifndef CASESENSITIVITYDEFAULT_NO
+#  if !defined(unix) && !defined(CASESENSITIVITYDEFAULT_YES)
+#    define CASESENSITIVITYDEFAULT_NO
+#  endif
+#endif
+
+
+#ifndef UNZ_BUFSIZE
+#define UNZ_BUFSIZE (16384)
+#endif
+
+#ifndef UNZ_MAXFILENAMEINZIP
+#define UNZ_MAXFILENAMEINZIP (256)
+#endif
+
+#ifndef ALLOC
+# define ALLOC(size) (malloc(size))
+#endif
+#ifndef TRYFREE
+# define TRYFREE(p) {if (p) free(p);}
+#endif
+
+#define SIZECENTRALDIRITEM (0x2e)
+#define SIZEZIPLOCALHEADER (0x1e)
+
+
+
+
+const char unz_copyright[] =
+   " unzip 1.01 Copyright 1998-2004 Gilles Vollant - http://www.winimage.com/zLibDll";
+
+/* unz_file_info_interntal contain internal info about a file in zipfile*/
+typedef struct unz_file_info_internal_s
+{
+    uLong offset_curfile;/* relative offset of local header 4 bytes */
+} unz_file_info_internal;
+
+
+/* file_in_zip_read_info_s contain internal information about a file in zipfile,
+    when reading and decompress it */
+typedef struct
+{
+    char  *read_buffer;         /* internal buffer for compressed data */
+    z_stream stream;            /* zLib stream structure for inflate */
+
+    uLong pos_in_zipfile;       /* position in byte on the zipfile, for fseek*/
+    uLong stream_initialised;   /* flag set if stream structure is initialised*/
+
+    uLong offset_local_extrafield;/* offset of the local extra field */
+    uInt  size_local_extrafield;/* size of the local extra field */
+    uLong pos_local_extrafield;   /* position in the local extra field in read*/
+
+    uLong crc32;                /* crc32 of all data uncompressed */
+    uLong crc32_wait;           /* crc32 we must obtain after decompress all */
+    uLong rest_read_compressed; /* number of byte to be decompressed */
+    uLong rest_read_uncompressed;/*number of byte to be obtained after decomp*/
+    zlib_filefunc_def z_filefunc;
+    voidpf filestream;        /* io structore of the zipfile */
+    uLong compression_method;   /* compression method (0==store) */
+    uLong byte_before_the_zipfile;/* byte before the zipfile, (>0 for sfx)*/
+    int   raw;
+} file_in_zip_read_info_s;
+
+
+/* unz_s contain internal information about the zipfile
+*/
+typedef struct
+{
+    zlib_filefunc_def z_filefunc;
+    voidpf filestream;        /* io structore of the zipfile */
+    unz_global_info gi;       /* public global information */
+    uLong byte_before_the_zipfile;/* byte before the zipfile, (>0 for sfx)*/
+    uLong num_file;             /* number of the current file in the zipfile*/
+    uLong pos_in_central_dir;   /* pos of the current file in the central dir*/
+    uLong current_file_ok;      /* flag about the usability of the current file*/
+    uLong central_pos;          /* position of the beginning of the central dir*/
+
+    uLong size_central_dir;     /* size of the central directory  */
+    uLong offset_central_dir;   /* offset of start of central directory with
+                                   respect to the starting disk number */
+
+    unz_file_info cur_file_info; /* public info about the current file in zip*/
+    unz_file_info_internal cur_file_info_internal; /* private info about it*/
+    file_in_zip_read_info_s* pfile_in_zip_read; /* structure about the current
+                                        file if we are decompressing it */
+    int encrypted;
+#    ifndef NOUNCRYPT
+    unsigned long keys[3];     /* keys defining the pseudo-random sequence */
+    const unsigned long* pcrc_32_tab;
+#    endif
+} unz_s;
+
+
+#ifndef NOUNCRYPT
+#include "crypt.h"
+#endif
+
+/* ===========================================================================
+     Read a byte from a gz_stream; update next_in and avail_in. Return EOF
+   for end of file.
+   IN assertion: the stream s has been sucessfully opened for reading.
+*/
+
+
+local int unzlocal_getByte OF((
+    const zlib_filefunc_def* pzlib_filefunc_def,
+    voidpf filestream,
+    int *pi));
+
+local int unzlocal_getByte(pzlib_filefunc_def,filestream,pi)
+    const zlib_filefunc_def* pzlib_filefunc_def;
+    voidpf filestream;
+    int *pi;
+{
+    unsigned char c;
+    int err = (int)ZREAD(*pzlib_filefunc_def,filestream,&c,1);
+    if (err==1)
+    {
+        *pi = (int)c;
+        return UNZ_OK;
+    }
+    else
+    {
+        if (ZERROR(*pzlib_filefunc_def,filestream))
+            return UNZ_ERRNO;
+        else
+            return UNZ_EOF;
+    }
+}
+
+
+/* ===========================================================================
+   Reads a long in LSB order from the given gz_stream. Sets
+*/
+local int unzlocal_getShort OF((
+    const zlib_filefunc_def* pzlib_filefunc_def,
+    voidpf filestream,
+    uLong *pX));
+
+local int unzlocal_getShort (pzlib_filefunc_def,filestream,pX)
+    const zlib_filefunc_def* pzlib_filefunc_def;
+    voidpf filestream;
+    uLong *pX;
+{
+    uLong x ;
+    int i;
+    int err;
+
+    err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x = (uLong)i;
+
+    if (err==UNZ_OK)
+        err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x += ((uLong)i)<<8;
+
+    if (err==UNZ_OK)
+        *pX = x;
+    else
+        *pX = 0;
+    return err;
+}
+
+local int unzlocal_getLong OF((
+    const zlib_filefunc_def* pzlib_filefunc_def,
+    voidpf filestream,
+    uLong *pX));
+
+local int unzlocal_getLong (pzlib_filefunc_def,filestream,pX)
+    const zlib_filefunc_def* pzlib_filefunc_def;
+    voidpf filestream;
+    uLong *pX;
+{
+    uLong x ;
+    int i;
+    int err;
+
+    err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x = (uLong)i;
+
+    if (err==UNZ_OK)
+        err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x += ((uLong)i)<<8;
+
+    if (err==UNZ_OK)
+        err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x += ((uLong)i)<<16;
+
+    if (err==UNZ_OK)
+        err = unzlocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x += ((uLong)i)<<24;
+
+    if (err==UNZ_OK)
+        *pX = x;
+    else
+        *pX = 0;
+    return err;
+}
+
+
+/* My own strcmpi / strcasecmp */
+local int strcmpcasenosensitive_internal (fileName1,fileName2)
+    const char* fileName1;
+    const char* fileName2;
+{
+    for (;;)
+    {
+        char c1=*(fileName1++);
+        char c2=*(fileName2++);
+        if ((c1>='a') && (c1<='z'))
+            c1 -= 0x20;
+        if ((c2>='a') && (c2<='z'))
+            c2 -= 0x20;
+        if (c1=='\0')
+            return ((c2=='\0') ? 0 : -1);
+        if (c2=='\0')
+            return 1;
+        if (c1<c2)
+            return -1;
+        if (c1>c2)
+            return 1;
+    }
+}
+
+
+#ifdef  CASESENSITIVITYDEFAULT_NO
+#define CASESENSITIVITYDEFAULTVALUE 2
+#else
+#define CASESENSITIVITYDEFAULTVALUE 1
+#endif
+
+#ifndef STRCMPCASENOSENTIVEFUNCTION
+#define STRCMPCASENOSENTIVEFUNCTION strcmpcasenosensitive_internal
+#endif
+
+/*
+   Compare two filename (fileName1,fileName2).
+   If iCaseSenisivity = 1, comparision is case sensitivity (like strcmp)
+   If iCaseSenisivity = 2, comparision is not case sensitivity (like strcmpi
+                                                                or strcasecmp)
+   If iCaseSenisivity = 0, case sensitivity is defaut of your operating system
+        (like 1 on Unix, 2 on Windows)
+
+*/
+extern int ZEXPORT unzStringFileNameCompare (fileName1,fileName2,iCaseSensitivity)
+    const char* fileName1;
+    const char* fileName2;
+    int iCaseSensitivity;
+{
+    if (iCaseSensitivity==0)
+        iCaseSensitivity=CASESENSITIVITYDEFAULTVALUE;
+
+    if (iCaseSensitivity==1)
+        return strcmp(fileName1,fileName2);
+
+    return STRCMPCASENOSENTIVEFUNCTION(fileName1,fileName2);
+}
+
+#ifndef BUFREADCOMMENT
+#define BUFREADCOMMENT (0x400)
+#endif
+
+/*
+  Locate the Central directory of a zipfile (at the end, just before
+    the global comment)
+*/
+local uLong unzlocal_SearchCentralDir OF((
+    const zlib_filefunc_def* pzlib_filefunc_def,
+    voidpf filestream));
+
+local uLong unzlocal_SearchCentralDir(pzlib_filefunc_def,filestream)
+    const zlib_filefunc_def* pzlib_filefunc_def;
+    voidpf filestream;
+{
+    unsigned char* buf;
+    uLong uSizeFile;
+    uLong uBackRead;
+    uLong uMaxBack=0xffff; /* maximum size of global comment */
+    uLong uPosFound=0;
+
+    if (ZSEEK(*pzlib_filefunc_def,filestream,0,ZLIB_FILEFUNC_SEEK_END) != 0)
+        return 0;
+
+
+    uSizeFile = ZTELL(*pzlib_filefunc_def,filestream);
+
+    if (uMaxBack>uSizeFile)
+        uMaxBack = uSizeFile;
+
+    buf = (unsigned char*)ALLOC(BUFREADCOMMENT+4);
+    if (buf==NULL)
+        return 0;
+
+    uBackRead = 4;
+    while (uBackRead<uMaxBack)
+    {
+        uLong uReadSize,uReadPos ;
+        int i;
+        if (uBackRead+BUFREADCOMMENT>uMaxBack)
+            uBackRead = uMaxBack;
+        else
+            uBackRead+=BUFREADCOMMENT;
+        uReadPos = uSizeFile-uBackRead ;
+
+        uReadSize = ((BUFREADCOMMENT+4) < (uSizeFile-uReadPos)) ?
+                     (BUFREADCOMMENT+4) : (uSizeFile-uReadPos);
+        if (ZSEEK(*pzlib_filefunc_def,filestream,uReadPos,ZLIB_FILEFUNC_SEEK_SET)!=0)
+            break;
+
+        if (ZREAD(*pzlib_filefunc_def,filestream,buf,uReadSize)!=uReadSize)
+            break;
+
+        for (i=(int)uReadSize-3; (i--)>0;)
+            if (((*(buf+i))==0x50) && ((*(buf+i+1))==0x4b) &&
+                ((*(buf+i+2))==0x05) && ((*(buf+i+3))==0x06))
+            {
+                uPosFound = uReadPos+i;
+                break;
+            }
+
+        if (uPosFound!=0)
+            break;
+    }
+    TRYFREE(buf);
+    return uPosFound;
+}
+
+/*
+  Open a Zip file. path contain the full pathname (by example,
+     on a Windows NT computer "c:\\test\\zlib114.zip" or on an Unix computer
+     "zlib/zlib114.zip".
+     If the zipfile cannot be opened (file doesn't exist or in not valid), the
+       return value is NULL.
+     Else, the return value is a unzFile Handle, usable with other function
+       of this unzip package.
+*/
+extern unzFile ZEXPORT unzOpen2 (path, pzlib_filefunc_def)
+    const char *path;
+    zlib_filefunc_def* pzlib_filefunc_def;
+{
+    unz_s us;
+    unz_s *s;
+    uLong central_pos,uL;
+
+    uLong number_disk;          /* number of the current dist, used for
+                                   spaning ZIP, unsupported, always 0*/
+    uLong number_disk_with_CD;  /* number the the disk with central dir, used
+                                   for spaning ZIP, unsupported, always 0*/
+    uLong number_entry_CD;      /* total number of entries in
+                                   the central dir
+                                   (same than number_entry on nospan) */
+
+    int err=UNZ_OK;
+
+    if (unz_copyright[0]!=' ')
+        return NULL;
+
+    if (pzlib_filefunc_def==NULL)
+        fill_fopen_filefunc(&us.z_filefunc);
+    else
+        us.z_filefunc = *pzlib_filefunc_def;
+
+    us.filestream= (*(us.z_filefunc.zopen_file))(us.z_filefunc.opaque,
+                                                 path,
+                                                 ZLIB_FILEFUNC_MODE_READ |
+                                                 ZLIB_FILEFUNC_MODE_EXISTING);
+    if (us.filestream==NULL)
+        return NULL;
+
+    central_pos = unzlocal_SearchCentralDir(&us.z_filefunc,us.filestream);
+    if (central_pos==0)
+        err=UNZ_ERRNO;
+
+    if (ZSEEK(us.z_filefunc, us.filestream,
+                                      central_pos,ZLIB_FILEFUNC_SEEK_SET)!=0)
+        err=UNZ_ERRNO;
+
+    /* the signature, already checked */
+    if (unzlocal_getLong(&us.z_filefunc, us.filestream,&uL)!=UNZ_OK)
+        err=UNZ_ERRNO;
+
+    /* number of this disk */
+    if (unzlocal_getShort(&us.z_filefunc, us.filestream,&number_disk)!=UNZ_OK)
+        err=UNZ_ERRNO;
+
+    /* number of the disk with the start of the central directory */
+    if (unzlocal_getShort(&us.z_filefunc, us.filestream,&number_disk_with_CD)!=UNZ_OK)
+        err=UNZ_ERRNO;
+
+    /* total number of entries in the central dir on this disk */
+    if (unzlocal_getShort(&us.z_filefunc, us.filestream,&us.gi.number_entry)!=UNZ_OK)
+        err=UNZ_ERRNO;
+
+    /* total number of entries in the central dir */
+    if (unzlocal_getShort(&us.z_filefunc, us.filestream,&number_entry_CD)!=UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if ((number_entry_CD!=us.gi.number_entry) ||
+        (number_disk_with_CD!=0) ||
+        (number_disk!=0))
+        err=UNZ_BADZIPFILE;
+
+    /* size of the central directory */
+    if (unzlocal_getLong(&us.z_filefunc, us.filestream,&us.size_central_dir)!=UNZ_OK)
+        err=UNZ_ERRNO;
+
+    /* offset of start of central directory with respect to the
+          starting disk number */
+    if (unzlocal_getLong(&us.z_filefunc, us.filestream,&us.offset_central_dir)!=UNZ_OK)
+        err=UNZ_ERRNO;
+
+    /* zipfile comment length */
+    if (unzlocal_getShort(&us.z_filefunc, us.filestream,&us.gi.size_comment)!=UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if ((central_pos<us.offset_central_dir+us.size_central_dir) &&
+        (err==UNZ_OK))
+        err=UNZ_BADZIPFILE;
+
+    if (err!=UNZ_OK)
+    {
+        ZCLOSE(us.z_filefunc, us.filestream);
+        return NULL;
+    }
+
+    us.byte_before_the_zipfile = central_pos -
+                            (us.offset_central_dir+us.size_central_dir);
+    us.central_pos = central_pos;
+    us.pfile_in_zip_read = NULL;
+    us.encrypted = 0;
+
+
+    s=(unz_s*)ALLOC(sizeof(unz_s));
+    *s=us;
+    unzGoToFirstFile((unzFile)s);
+    return (unzFile)s;
+}
+
+
+extern unzFile ZEXPORT unzOpen (path)
+    const char *path;
+{
+    return unzOpen2(path, NULL);
+}
+
+/*
+  Close a ZipFile opened with unzipOpen.
+  If there is files inside the .Zip opened with unzipOpenCurrentFile (see later),
+    these files MUST be closed with unzipCloseCurrentFile before call unzipClose.
+  return UNZ_OK if there is no problem. */
+extern int ZEXPORT unzClose (file)
+    unzFile file;
+{
+    unz_s* s;
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+
+    if (s->pfile_in_zip_read!=NULL)
+        unzCloseCurrentFile(file);
+
+    ZCLOSE(s->z_filefunc, s->filestream);
+    TRYFREE(s);
+    return UNZ_OK;
+}
+
+
+/*
+  Write info about the ZipFile in the *pglobal_info structure.
+  No preparation of the structure is needed
+  return UNZ_OK if there is no problem. */
+extern int ZEXPORT unzGetGlobalInfo (file,pglobal_info)
+    unzFile file;
+    unz_global_info *pglobal_info;
+{
+    unz_s* s;
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    *pglobal_info=s->gi;
+    return UNZ_OK;
+}
+
+
+/*
+   Translate date/time from Dos format to tm_unz (readable more easilty)
+*/
+local void unzlocal_DosDateToTmuDate (ulDosDate, ptm)
+    uLong ulDosDate;
+    tm_unz* ptm;
+{
+    uLong uDate;
+    uDate = (uLong)(ulDosDate>>16);
+    ptm->tm_mday = (uInt)(uDate&0x1f) ;
+    ptm->tm_mon =  (uInt)((((uDate)&0x1E0)/0x20)-1) ;
+    ptm->tm_year = (uInt)(((uDate&0x0FE00)/0x0200)+1980) ;
+
+    ptm->tm_hour = (uInt) ((ulDosDate &0xF800)/0x800);
+    ptm->tm_min =  (uInt) ((ulDosDate&0x7E0)/0x20) ;
+    ptm->tm_sec =  (uInt) (2*(ulDosDate&0x1f)) ;
+}
+
+/*
+  Get Info about the current file in the zipfile, with internal only info
+*/
+local int unzlocal_GetCurrentFileInfoInternal OF((unzFile file,
+                                                  unz_file_info *pfile_info,
+                                                  unz_file_info_internal
+                                                  *pfile_info_internal,
+                                                  char *szFileName,
+                                                  uLong fileNameBufferSize,
+                                                  void *extraField,
+                                                  uLong extraFieldBufferSize,
+                                                  char *szComment,
+                                                  uLong commentBufferSize));
+
+local int unzlocal_GetCurrentFileInfoInternal (file,
+                                              pfile_info,
+                                              pfile_info_internal,
+                                              szFileName, fileNameBufferSize,
+                                              extraField, extraFieldBufferSize,
+                                              szComment,  commentBufferSize)
+    unzFile file;
+    unz_file_info *pfile_info;
+    unz_file_info_internal *pfile_info_internal;
+    char *szFileName;
+    uLong fileNameBufferSize;
+    void *extraField;
+    uLong extraFieldBufferSize;
+    char *szComment;
+    uLong commentBufferSize;
+{
+    unz_s* s;
+    unz_file_info file_info;
+    unz_file_info_internal file_info_internal;
+    int err=UNZ_OK;
+    uLong uMagic;
+    long lSeek=0;
+
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    if (ZSEEK(s->z_filefunc, s->filestream,
+              s->pos_in_central_dir+s->byte_before_the_zipfile,
+              ZLIB_FILEFUNC_SEEK_SET)!=0)
+        err=UNZ_ERRNO;
+
+
+    /* we check the magic */
+    if (err==UNZ_OK)
+        if (unzlocal_getLong(&s->z_filefunc, s->filestream,&uMagic) != UNZ_OK)
+            err=UNZ_ERRNO;
+        else if (uMagic!=0x02014b50)
+            err=UNZ_BADZIPFILE;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&file_info.version) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&file_info.version_needed) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&file_info.flag) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&file_info.compression_method) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getLong(&s->z_filefunc, s->filestream,&file_info.dosDate) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    unzlocal_DosDateToTmuDate(file_info.dosDate,&file_info.tmu_date);
+
+    if (unzlocal_getLong(&s->z_filefunc, s->filestream,&file_info.crc) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getLong(&s->z_filefunc, s->filestream,&file_info.compressed_size) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getLong(&s->z_filefunc, s->filestream,&file_info.uncompressed_size) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&file_info.size_filename) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&file_info.size_file_extra) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&file_info.size_file_comment) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&file_info.disk_num_start) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&file_info.internal_fa) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getLong(&s->z_filefunc, s->filestream,&file_info.external_fa) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getLong(&s->z_filefunc, s->filestream,&file_info_internal.offset_curfile) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    lSeek+=file_info.size_filename;
+    if ((err==UNZ_OK) && (szFileName!=NULL))
+    {
+        uLong uSizeRead ;
+        if (file_info.size_filename<fileNameBufferSize)
+        {
+            *(szFileName+file_info.size_filename)='\0';
+            uSizeRead = file_info.size_filename;
+        }
+        else
+            uSizeRead = fileNameBufferSize;
+
+        if ((file_info.size_filename>0) && (fileNameBufferSize>0))
+            if (ZREAD(s->z_filefunc, s->filestream,szFileName,uSizeRead)!=uSizeRead)
+                err=UNZ_ERRNO;
+        lSeek -= uSizeRead;
+    }
+
+
+    if ((err==UNZ_OK) && (extraField!=NULL))
+    {
+        uLong uSizeRead ;
+        if (file_info.size_file_extra<extraFieldBufferSize)
+            uSizeRead = file_info.size_file_extra;
+        else
+            uSizeRead = extraFieldBufferSize;
+
+        if (lSeek!=0)
+            if (ZSEEK(s->z_filefunc, s->filestream,lSeek,ZLIB_FILEFUNC_SEEK_CUR)==0)
+                lSeek=0;
+            else
+                err=UNZ_ERRNO;
+        if ((file_info.size_file_extra>0) && (extraFieldBufferSize>0))
+            if (ZREAD(s->z_filefunc, s->filestream,extraField,uSizeRead)!=uSizeRead)
+                err=UNZ_ERRNO;
+        lSeek += file_info.size_file_extra - uSizeRead;
+    }
+    else
+        lSeek+=file_info.size_file_extra;
+
+
+    if ((err==UNZ_OK) && (szComment!=NULL))
+    {
+        uLong uSizeRead ;
+        if (file_info.size_file_comment<commentBufferSize)
+        {
+            *(szComment+file_info.size_file_comment)='\0';
+            uSizeRead = file_info.size_file_comment;
+        }
+        else
+            uSizeRead = commentBufferSize;
+
+        if (lSeek!=0)
+            if (ZSEEK(s->z_filefunc, s->filestream,lSeek,ZLIB_FILEFUNC_SEEK_CUR)==0)
+                lSeek=0;
+            else
+                err=UNZ_ERRNO;
+        if ((file_info.size_file_comment>0) && (commentBufferSize>0))
+            if (ZREAD(s->z_filefunc, s->filestream,szComment,uSizeRead)!=uSizeRead)
+                err=UNZ_ERRNO;
+        lSeek+=file_info.size_file_comment - uSizeRead;
+    }
+    else
+        lSeek+=file_info.size_file_comment;
+
+    if ((err==UNZ_OK) && (pfile_info!=NULL))
+        *pfile_info=file_info;
+
+    if ((err==UNZ_OK) && (pfile_info_internal!=NULL))
+        *pfile_info_internal=file_info_internal;
+
+    return err;
+}
+
+
+
+/*
+  Write info about the ZipFile in the *pglobal_info structure.
+  No preparation of the structure is needed
+  return UNZ_OK if there is no problem.
+*/
+extern int ZEXPORT unzGetCurrentFileInfo (file,
+                                          pfile_info,
+                                          szFileName, fileNameBufferSize,
+                                          extraField, extraFieldBufferSize,
+                                          szComment,  commentBufferSize)
+    unzFile file;
+    unz_file_info *pfile_info;
+    char *szFileName;
+    uLong fileNameBufferSize;
+    void *extraField;
+    uLong extraFieldBufferSize;
+    char *szComment;
+    uLong commentBufferSize;
+{
+    return unzlocal_GetCurrentFileInfoInternal(file,pfile_info,NULL,
+                                                szFileName,fileNameBufferSize,
+                                                extraField,extraFieldBufferSize,
+                                                szComment,commentBufferSize);
+}
+
+/*
+  Set the current file of the zipfile to the first file.
+  return UNZ_OK if there is no problem
+*/
+extern int ZEXPORT unzGoToFirstFile (file)
+    unzFile file;
+{
+    int err=UNZ_OK;
+    unz_s* s;
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    s->pos_in_central_dir=s->offset_central_dir;
+    s->num_file=0;
+    err=unzlocal_GetCurrentFileInfoInternal(file,&s->cur_file_info,
+                                             &s->cur_file_info_internal,
+                                             NULL,0,NULL,0,NULL,0);
+    s->current_file_ok = (err == UNZ_OK);
+    return err;
+}
+
+/*
+  Set the current file of the zipfile to the next file.
+  return UNZ_OK if there is no problem
+  return UNZ_END_OF_LIST_OF_FILE if the actual file was the latest.
+*/
+extern int ZEXPORT unzGoToNextFile (file)
+    unzFile file;
+{
+    unz_s* s;
+    int err;
+
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    if (!s->current_file_ok)
+        return UNZ_END_OF_LIST_OF_FILE;
+    if (s->gi.number_entry != 0xffff)    /* 2^16 files overflow hack */
+      if (s->num_file+1==s->gi.number_entry)
+        return UNZ_END_OF_LIST_OF_FILE;
+
+    s->pos_in_central_dir += SIZECENTRALDIRITEM + s->cur_file_info.size_filename +
+            s->cur_file_info.size_file_extra + s->cur_file_info.size_file_comment ;
+    s->num_file++;
+    err = unzlocal_GetCurrentFileInfoInternal(file,&s->cur_file_info,
+                                               &s->cur_file_info_internal,
+                                               NULL,0,NULL,0,NULL,0);
+    s->current_file_ok = (err == UNZ_OK);
+    return err;
+}
+
+
+/*
+  Try locate the file szFileName in the zipfile.
+  For the iCaseSensitivity signification, see unzipStringFileNameCompare
+
+  return value :
+  UNZ_OK if the file is found. It becomes the current file.
+  UNZ_END_OF_LIST_OF_FILE if the file is not found
+*/
+extern int ZEXPORT unzLocateFile (file, szFileName, iCaseSensitivity)
+    unzFile file;
+    const char *szFileName;
+    int iCaseSensitivity;
+{
+    unz_s* s;
+    int err;
+
+    /* We remember the 'current' position in the file so that we can jump
+     * back there if we fail.
+     */
+    unz_file_info cur_file_infoSaved;
+    unz_file_info_internal cur_file_info_internalSaved;
+    uLong num_fileSaved;
+    uLong pos_in_central_dirSaved;
+
+
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+
+    if (strlen(szFileName)>=UNZ_MAXFILENAMEINZIP)
+        return UNZ_PARAMERROR;
+
+    s=(unz_s*)file;
+    if (!s->current_file_ok)
+        return UNZ_END_OF_LIST_OF_FILE;
+
+    /* Save the current state */
+    num_fileSaved = s->num_file;
+    pos_in_central_dirSaved = s->pos_in_central_dir;
+    cur_file_infoSaved = s->cur_file_info;
+    cur_file_info_internalSaved = s->cur_file_info_internal;
+
+    err = unzGoToFirstFile(file);
+
+    while (err == UNZ_OK)
+    {
+        char szCurrentFileName[UNZ_MAXFILENAMEINZIP+1];
+        err = unzGetCurrentFileInfo(file,NULL,
+                                    szCurrentFileName,sizeof(szCurrentFileName)-1,
+                                    NULL,0,NULL,0);
+        if (err == UNZ_OK)
+        {
+            if (unzStringFileNameCompare(szCurrentFileName,
+                                            szFileName,iCaseSensitivity)==0)
+                return UNZ_OK;
+            err = unzGoToNextFile(file);
+        }
+    }
+
+    /* We failed, so restore the state of the 'current file' to where we
+     * were.
+     */
+    s->num_file = num_fileSaved ;
+    s->pos_in_central_dir = pos_in_central_dirSaved ;
+    s->cur_file_info = cur_file_infoSaved;
+    s->cur_file_info_internal = cur_file_info_internalSaved;
+    return err;
+}
+
+
+/*
+///////////////////////////////////////////
+// Contributed by Ryan Haksi (mailto://cryogen@infoserve.net)
+// I need random access
+//
+// Further optimization could be realized by adding an ability
+// to cache the directory in memory. The goal being a single
+// comprehensive file read to put the file I need in a memory.
+*/
+
+/*
+typedef struct unz_file_pos_s
+{
+    uLong pos_in_zip_directory;   // offset in file
+    uLong num_of_file;            // # of file
+} unz_file_pos;
+*/
+
+extern int ZEXPORT unzGetFilePos(file, file_pos)
+    unzFile file;
+    unz_file_pos* file_pos;
+{
+    unz_s* s;
+
+    if (file==NULL || file_pos==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    if (!s->current_file_ok)
+        return UNZ_END_OF_LIST_OF_FILE;
+
+    file_pos->pos_in_zip_directory  = s->pos_in_central_dir;
+    file_pos->num_of_file           = s->num_file;
+
+    return UNZ_OK;
+}
+
+extern int ZEXPORT unzGoToFilePos(file, file_pos)
+    unzFile file;
+    unz_file_pos* file_pos;
+{
+    unz_s* s;
+    int err;
+
+    if (file==NULL || file_pos==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+
+    /* jump to the right spot */
+    s->pos_in_central_dir = file_pos->pos_in_zip_directory;
+    s->num_file           = file_pos->num_of_file;
+
+    /* set the current file */
+    err = unzlocal_GetCurrentFileInfoInternal(file,&s->cur_file_info,
+                                               &s->cur_file_info_internal,
+                                               NULL,0,NULL,0,NULL,0);
+    /* return results */
+    s->current_file_ok = (err == UNZ_OK);
+    return err;
+}
+
+/*
+// Unzip Helper Functions - should be here?
+///////////////////////////////////////////
+*/
+
+/*
+  Read the local header of the current zipfile
+  Check the coherency of the local header and info in the end of central
+        directory about this file
+  store in *piSizeVar the size of extra info in local header
+        (filename and size of extra field data)
+*/
+local int unzlocal_CheckCurrentFileCoherencyHeader (s,piSizeVar,
+                                                    poffset_local_extrafield,
+                                                    psize_local_extrafield)
+    unz_s* s;
+    uInt* piSizeVar;
+    uLong *poffset_local_extrafield;
+    uInt  *psize_local_extrafield;
+{
+    uLong uMagic,uData,uFlags;
+    uLong size_filename;
+    uLong size_extra_field;
+    int err=UNZ_OK;
+
+    *piSizeVar = 0;
+    *poffset_local_extrafield = 0;
+    *psize_local_extrafield = 0;
+
+    if (ZSEEK(s->z_filefunc, s->filestream,s->cur_file_info_internal.offset_curfile +
+                                s->byte_before_the_zipfile,ZLIB_FILEFUNC_SEEK_SET)!=0)
+        return UNZ_ERRNO;
+
+
+    if (err==UNZ_OK)
+        if (unzlocal_getLong(&s->z_filefunc, s->filestream,&uMagic) != UNZ_OK)
+            err=UNZ_ERRNO;
+        else if (uMagic!=0x04034b50)
+            err=UNZ_BADZIPFILE;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&uData) != UNZ_OK)
+        err=UNZ_ERRNO;
+/*
+    else if ((err==UNZ_OK) && (uData!=s->cur_file_info.wVersion))
+        err=UNZ_BADZIPFILE;
+*/
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&uFlags) != UNZ_OK)
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&uData) != UNZ_OK)
+        err=UNZ_ERRNO;
+    else if ((err==UNZ_OK) && (uData!=s->cur_file_info.compression_method))
+        err=UNZ_BADZIPFILE;
+
+    if ((err==UNZ_OK) && (s->cur_file_info.compression_method!=0) &&
+                         (s->cur_file_info.compression_method!=Z_DEFLATED))
+        err=UNZ_BADZIPFILE;
+
+    if (unzlocal_getLong(&s->z_filefunc, s->filestream,&uData) != UNZ_OK) /* date/time */
+        err=UNZ_ERRNO;
+
+    if (unzlocal_getLong(&s->z_filefunc, s->filestream,&uData) != UNZ_OK) /* crc */
+        err=UNZ_ERRNO;
+    else if ((err==UNZ_OK) && (uData!=s->cur_file_info.crc) &&
+                              ((uFlags & 8)==0))
+        err=UNZ_BADZIPFILE;
+
+    if (unzlocal_getLong(&s->z_filefunc, s->filestream,&uData) != UNZ_OK) /* size compr */
+        err=UNZ_ERRNO;
+    else if ((err==UNZ_OK) && (uData!=s->cur_file_info.compressed_size) &&
+                              ((uFlags & 8)==0))
+        err=UNZ_BADZIPFILE;
+
+    if (unzlocal_getLong(&s->z_filefunc, s->filestream,&uData) != UNZ_OK) /* size uncompr */
+        err=UNZ_ERRNO;
+    else if ((err==UNZ_OK) && (uData!=s->cur_file_info.uncompressed_size) &&
+                              ((uFlags & 8)==0))
+        err=UNZ_BADZIPFILE;
+
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&size_filename) != UNZ_OK)
+        err=UNZ_ERRNO;
+    else if ((err==UNZ_OK) && (size_filename!=s->cur_file_info.size_filename))
+        err=UNZ_BADZIPFILE;
+
+    *piSizeVar += (uInt)size_filename;
+
+    if (unzlocal_getShort(&s->z_filefunc, s->filestream,&size_extra_field) != UNZ_OK)
+        err=UNZ_ERRNO;
+    *poffset_local_extrafield= s->cur_file_info_internal.offset_curfile +
+                                    SIZEZIPLOCALHEADER + size_filename;
+    *psize_local_extrafield = (uInt)size_extra_field;
+
+    *piSizeVar += (uInt)size_extra_field;
+
+    return err;
+}
+
+/*
+  Open for reading data the current file in the zipfile.
+  If there is no error and the file is opened, the return value is UNZ_OK.
+*/
+extern int ZEXPORT unzOpenCurrentFile3 (file, method, level, raw, password)
+    unzFile file;
+    int* method;
+    int* level;
+    int raw;
+    const char* password;
+{
+    int err=UNZ_OK;
+    uInt iSizeVar;
+    unz_s* s;
+    file_in_zip_read_info_s* pfile_in_zip_read_info;
+    uLong offset_local_extrafield;  /* offset of the local extra field */
+    uInt  size_local_extrafield;    /* size of the local extra field */
+#    ifndef NOUNCRYPT
+    char source[12];
+#    else
+    if (password != NULL)
+        return UNZ_PARAMERROR;
+#    endif
+
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    if (!s->current_file_ok)
+        return UNZ_PARAMERROR;
+
+    if (s->pfile_in_zip_read != NULL)
+        unzCloseCurrentFile(file);
+
+    if (unzlocal_CheckCurrentFileCoherencyHeader(s,&iSizeVar,
+                &offset_local_extrafield,&size_local_extrafield)!=UNZ_OK)
+        return UNZ_BADZIPFILE;
+
+    pfile_in_zip_read_info = (file_in_zip_read_info_s*)
+                                        ALLOC(sizeof(file_in_zip_read_info_s));
+    if (pfile_in_zip_read_info==NULL)
+        return UNZ_INTERNALERROR;
+
+    pfile_in_zip_read_info->read_buffer=(char*)ALLOC(UNZ_BUFSIZE);
+    pfile_in_zip_read_info->offset_local_extrafield = offset_local_extrafield;
+    pfile_in_zip_read_info->size_local_extrafield = size_local_extrafield;
+    pfile_in_zip_read_info->pos_local_extrafield=0;
+    pfile_in_zip_read_info->raw=raw;
+
+    if (pfile_in_zip_read_info->read_buffer==NULL)
+    {
+        TRYFREE(pfile_in_zip_read_info);
+        return UNZ_INTERNALERROR;
+    }
+
+    pfile_in_zip_read_info->stream_initialised=0;
+
+    if (method!=NULL)
+        *method = (int)s->cur_file_info.compression_method;
+
+    if (level!=NULL)
+    {
+        *level = 6;
+        switch (s->cur_file_info.flag & 0x06)
+        {
+          case 6 : *level = 1; break;
+          case 4 : *level = 2; break;
+          case 2 : *level = 9; break;
+        }
+    }
+
+    if ((s->cur_file_info.compression_method!=0) &&
+        (s->cur_file_info.compression_method!=Z_DEFLATED))
+        err=UNZ_BADZIPFILE;
+
+    pfile_in_zip_read_info->crc32_wait=s->cur_file_info.crc;
+    pfile_in_zip_read_info->crc32=0;
+    pfile_in_zip_read_info->compression_method =
+            s->cur_file_info.compression_method;
+    pfile_in_zip_read_info->filestream=s->filestream;
+    pfile_in_zip_read_info->z_filefunc=s->z_filefunc;
+    pfile_in_zip_read_info->byte_before_the_zipfile=s->byte_before_the_zipfile;
+
+    pfile_in_zip_read_info->stream.total_out = 0;
+
+    if ((s->cur_file_info.compression_method==Z_DEFLATED) &&
+        (!raw))
+    {
+      pfile_in_zip_read_info->stream.zalloc = (alloc_func)0;
+      pfile_in_zip_read_info->stream.zfree = (free_func)0;
+      pfile_in_zip_read_info->stream.opaque = (voidpf)0;
+      pfile_in_zip_read_info->stream.next_in = (voidpf)0;
+      pfile_in_zip_read_info->stream.avail_in = 0;
+
+      err=inflateInit2(&pfile_in_zip_read_info->stream, -MAX_WBITS);
+      if (err == Z_OK)
+        pfile_in_zip_read_info->stream_initialised=1;
+      else
+      {
+        TRYFREE(pfile_in_zip_read_info);
+        return err;
+      }
+        /* windowBits is passed < 0 to tell that there is no zlib header.
+         * Note that in this case inflate *requires* an extra "dummy" byte
+         * after the compressed stream in order to complete decompression and
+         * return Z_STREAM_END.
+         * In unzip, i don't wait absolutely Z_STREAM_END because I known the
+         * size of both compressed and uncompressed data
+         */
+    }
+    pfile_in_zip_read_info->rest_read_compressed =
+            s->cur_file_info.compressed_size ;
+    pfile_in_zip_read_info->rest_read_uncompressed =
+            s->cur_file_info.uncompressed_size ;
+
+
+    pfile_in_zip_read_info->pos_in_zipfile =
+            s->cur_file_info_internal.offset_curfile + SIZEZIPLOCALHEADER +
+              iSizeVar;
+
+    pfile_in_zip_read_info->stream.avail_in = (uInt)0;
+
+    s->pfile_in_zip_read = pfile_in_zip_read_info;
+
+#    ifndef NOUNCRYPT
+    if (password != NULL)
+    {
+        int i;
+        s->pcrc_32_tab = get_crc_table();
+        init_keys(password,s->keys,s->pcrc_32_tab);
+        if (ZSEEK(s->z_filefunc, s->filestream,
+                  s->pfile_in_zip_read->pos_in_zipfile +
+                     s->pfile_in_zip_read->byte_before_the_zipfile,
+                  SEEK_SET)!=0)
+            return UNZ_INTERNALERROR;
+        if(ZREAD(s->z_filefunc, s->filestream,source, 12)<12)
+            return UNZ_INTERNALERROR;
+
+        for (i = 0; i<12; i++)
+            zdecode(s->keys,s->pcrc_32_tab,source[i]);
+
+        s->pfile_in_zip_read->pos_in_zipfile+=12;
+        s->encrypted=1;
+    }
+#    endif
+
+
+    return UNZ_OK;
+}
+
+extern int ZEXPORT unzOpenCurrentFile (file)
+    unzFile file;
+{
+    return unzOpenCurrentFile3(file, NULL, NULL, 0, NULL);
+}
+
+extern int ZEXPORT unzOpenCurrentFilePassword (file, password)
+    unzFile file;
+    const char* password;
+{
+    return unzOpenCurrentFile3(file, NULL, NULL, 0, password);
+}
+
+extern int ZEXPORT unzOpenCurrentFile2 (file,method,level,raw)
+    unzFile file;
+    int* method;
+    int* level;
+    int raw;
+{
+    return unzOpenCurrentFile3(file, method, level, raw, NULL);
+}
+
+/*
+  Read bytes from the current file.
+  buf contain buffer where data must be copied
+  len the size of buf.
+
+  return the number of byte copied if somes bytes are copied
+  return 0 if the end of file was reached
+  return <0 with error code if there is an error
+    (UNZ_ERRNO for IO error, or zLib error for uncompress error)
+*/
+extern int ZEXPORT unzReadCurrentFile  (file, buf, len)
+    unzFile file;
+    voidp buf;
+    unsigned len;
+{
+    int err=UNZ_OK;
+    uInt iRead = 0;
+    unz_s* s;
+    file_in_zip_read_info_s* pfile_in_zip_read_info;
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    pfile_in_zip_read_info=s->pfile_in_zip_read;
+
+    if (pfile_in_zip_read_info==NULL)
+        return UNZ_PARAMERROR;
+
+
+    if ((pfile_in_zip_read_info->read_buffer == NULL))
+        return UNZ_END_OF_LIST_OF_FILE;
+    if (len==0)
+        return 0;
+
+    pfile_in_zip_read_info->stream.next_out = (Bytef*)buf;
+
+    pfile_in_zip_read_info->stream.avail_out = (uInt)len;
+
+    if ((len>pfile_in_zip_read_info->rest_read_uncompressed) &&
+        (!(pfile_in_zip_read_info->raw)))
+        pfile_in_zip_read_info->stream.avail_out =
+            (uInt)pfile_in_zip_read_info->rest_read_uncompressed;
+
+    if ((len>pfile_in_zip_read_info->rest_read_compressed+
+           pfile_in_zip_read_info->stream.avail_in) &&
+         (pfile_in_zip_read_info->raw))
+        pfile_in_zip_read_info->stream.avail_out =
+            (uInt)pfile_in_zip_read_info->rest_read_compressed+
+            pfile_in_zip_read_info->stream.avail_in;
+
+    while (pfile_in_zip_read_info->stream.avail_out>0)
+    {
+        if ((pfile_in_zip_read_info->stream.avail_in==0) &&
+            (pfile_in_zip_read_info->rest_read_compressed>0))
+        {
+            uInt uReadThis = UNZ_BUFSIZE;
+            if (pfile_in_zip_read_info->rest_read_compressed<uReadThis)
+                uReadThis = (uInt)pfile_in_zip_read_info->rest_read_compressed;
+            if (uReadThis == 0)
+                return UNZ_EOF;
+            if (ZSEEK(pfile_in_zip_read_info->z_filefunc,
+                      pfile_in_zip_read_info->filestream,
+                      pfile_in_zip_read_info->pos_in_zipfile +
+                         pfile_in_zip_read_info->byte_before_the_zipfile,
+                         ZLIB_FILEFUNC_SEEK_SET)!=0)
+                return UNZ_ERRNO;
+            if (ZREAD(pfile_in_zip_read_info->z_filefunc,
+                      pfile_in_zip_read_info->filestream,
+                      pfile_in_zip_read_info->read_buffer,
+                      uReadThis)!=uReadThis)
+                return UNZ_ERRNO;
+
+
+#            ifndef NOUNCRYPT
+            if(s->encrypted)
+            {
+                uInt i;
+                for(i=0;i<uReadThis;i++)
+                  pfile_in_zip_read_info->read_buffer[i] =
+                      zdecode(s->keys,s->pcrc_32_tab,
+                              pfile_in_zip_read_info->read_buffer[i]);
+            }
+#            endif
+
+
+            pfile_in_zip_read_info->pos_in_zipfile += uReadThis;
+
+            pfile_in_zip_read_info->rest_read_compressed-=uReadThis;
+
+            pfile_in_zip_read_info->stream.next_in =
+                (Bytef*)pfile_in_zip_read_info->read_buffer;
+            pfile_in_zip_read_info->stream.avail_in = (uInt)uReadThis;
+        }
+
+        if ((pfile_in_zip_read_info->compression_method==0) || (pfile_in_zip_read_info->raw))
+        {
+            uInt uDoCopy,i ;
+
+            if ((pfile_in_zip_read_info->stream.avail_in == 0) &&
+                (pfile_in_zip_read_info->rest_read_compressed == 0))
+                return (iRead==0) ? UNZ_EOF : iRead;
+
+            if (pfile_in_zip_read_info->stream.avail_out <
+                            pfile_in_zip_read_info->stream.avail_in)
+                uDoCopy = pfile_in_zip_read_info->stream.avail_out ;
+            else
+                uDoCopy = pfile_in_zip_read_info->stream.avail_in ;
+
+            for (i=0;i<uDoCopy;i++)
+                *(pfile_in_zip_read_info->stream.next_out+i) =
+                        *(pfile_in_zip_read_info->stream.next_in+i);
+
+            pfile_in_zip_read_info->crc32 = crc32(pfile_in_zip_read_info->crc32,
+                                pfile_in_zip_read_info->stream.next_out,
+                                uDoCopy);
+            pfile_in_zip_read_info->rest_read_uncompressed-=uDoCopy;
+            pfile_in_zip_read_info->stream.avail_in -= uDoCopy;
+            pfile_in_zip_read_info->stream.avail_out -= uDoCopy;
+            pfile_in_zip_read_info->stream.next_out += uDoCopy;
+            pfile_in_zip_read_info->stream.next_in += uDoCopy;
+            pfile_in_zip_read_info->stream.total_out += uDoCopy;
+            iRead += uDoCopy;
+        }
+        else
+        {
+            uLong uTotalOutBefore,uTotalOutAfter;
+            const Bytef *bufBefore;
+            uLong uOutThis;
+            int flush=Z_SYNC_FLUSH;
+
+            uTotalOutBefore = pfile_in_zip_read_info->stream.total_out;
+            bufBefore = pfile_in_zip_read_info->stream.next_out;
+
+            /*
+            if ((pfile_in_zip_read_info->rest_read_uncompressed ==
+                     pfile_in_zip_read_info->stream.avail_out) &&
+                (pfile_in_zip_read_info->rest_read_compressed == 0))
+                flush = Z_FINISH;
+            */
+            err=inflate(&pfile_in_zip_read_info->stream,flush);
+
+            if ((err>=0) && (pfile_in_zip_read_info->stream.msg!=NULL))
+              err = Z_DATA_ERROR;
+
+            uTotalOutAfter = pfile_in_zip_read_info->stream.total_out;
+            uOutThis = uTotalOutAfter-uTotalOutBefore;
+
+            pfile_in_zip_read_info->crc32 =
+                crc32(pfile_in_zip_read_info->crc32,bufBefore,
+                        (uInt)(uOutThis));
+
+            pfile_in_zip_read_info->rest_read_uncompressed -=
+                uOutThis;
+
+            iRead += (uInt)(uTotalOutAfter - uTotalOutBefore);
+
+            if (err==Z_STREAM_END)
+                return (iRead==0) ? UNZ_EOF : iRead;
+            if (err!=Z_OK)
+                break;
+        }
+    }
+
+    if (err==Z_OK)
+        return iRead;
+    return err;
+}
+
+
+/*
+  Give the current position in uncompressed data
+*/
+extern z_off_t ZEXPORT unztell (file)
+    unzFile file;
+{
+    unz_s* s;
+    file_in_zip_read_info_s* pfile_in_zip_read_info;
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    pfile_in_zip_read_info=s->pfile_in_zip_read;
+
+    if (pfile_in_zip_read_info==NULL)
+        return UNZ_PARAMERROR;
+
+    return (z_off_t)pfile_in_zip_read_info->stream.total_out;
+}
+
+
+/*
+  return 1 if the end of file was reached, 0 elsewhere
+*/
+extern int ZEXPORT unzeof (file)
+    unzFile file;
+{
+    unz_s* s;
+    file_in_zip_read_info_s* pfile_in_zip_read_info;
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    pfile_in_zip_read_info=s->pfile_in_zip_read;
+
+    if (pfile_in_zip_read_info==NULL)
+        return UNZ_PARAMERROR;
+
+    if (pfile_in_zip_read_info->rest_read_uncompressed == 0)
+        return 1;
+    else
+        return 0;
+}
+
+
+
+/*
+  Read extra field from the current file (opened by unzOpenCurrentFile)
+  This is the local-header version of the extra field (sometimes, there is
+    more info in the local-header version than in the central-header)
+
+  if buf==NULL, it return the size of the local extra field that can be read
+
+  if buf!=NULL, len is the size of the buffer, the extra header is copied in
+    buf.
+  the return value is the number of bytes copied in buf, or (if <0)
+    the error code
+*/
+extern int ZEXPORT unzGetLocalExtrafield (file,buf,len)
+    unzFile file;
+    voidp buf;
+    unsigned len;
+{
+    unz_s* s;
+    file_in_zip_read_info_s* pfile_in_zip_read_info;
+    uInt read_now;
+    uLong size_to_read;
+
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    pfile_in_zip_read_info=s->pfile_in_zip_read;
+
+    if (pfile_in_zip_read_info==NULL)
+        return UNZ_PARAMERROR;
+
+    size_to_read = (pfile_in_zip_read_info->size_local_extrafield -
+                pfile_in_zip_read_info->pos_local_extrafield);
+
+    if (buf==NULL)
+        return (int)size_to_read;
+
+    if (len>size_to_read)
+        read_now = (uInt)size_to_read;
+    else
+        read_now = (uInt)len ;
+
+    if (read_now==0)
+        return 0;
+
+    if (ZSEEK(pfile_in_zip_read_info->z_filefunc,
+              pfile_in_zip_read_info->filestream,
+              pfile_in_zip_read_info->offset_local_extrafield +
+              pfile_in_zip_read_info->pos_local_extrafield,
+              ZLIB_FILEFUNC_SEEK_SET)!=0)
+        return UNZ_ERRNO;
+
+    if (ZREAD(pfile_in_zip_read_info->z_filefunc,
+              pfile_in_zip_read_info->filestream,
+              buf,read_now)!=read_now)
+        return UNZ_ERRNO;
+
+    return (int)read_now;
+}
+
+/*
+  Close the file in zip opened with unzipOpenCurrentFile
+  Return UNZ_CRCERROR if all the file was read but the CRC is not good
+*/
+extern int ZEXPORT unzCloseCurrentFile (file)
+    unzFile file;
+{
+    int err=UNZ_OK;
+
+    unz_s* s;
+    file_in_zip_read_info_s* pfile_in_zip_read_info;
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    pfile_in_zip_read_info=s->pfile_in_zip_read;
+
+    if (pfile_in_zip_read_info==NULL)
+        return UNZ_PARAMERROR;
+
+
+    if ((pfile_in_zip_read_info->rest_read_uncompressed == 0) &&
+        (!pfile_in_zip_read_info->raw))
+    {
+        if (pfile_in_zip_read_info->crc32 != pfile_in_zip_read_info->crc32_wait)
+            err=UNZ_CRCERROR;
+    }
+
+
+    TRYFREE(pfile_in_zip_read_info->read_buffer);
+    pfile_in_zip_read_info->read_buffer = NULL;
+    if (pfile_in_zip_read_info->stream_initialised)
+        inflateEnd(&pfile_in_zip_read_info->stream);
+
+    pfile_in_zip_read_info->stream_initialised = 0;
+    TRYFREE(pfile_in_zip_read_info);
+
+    s->pfile_in_zip_read=NULL;
+
+    return err;
+}
+
+
+/*
+  Get the global comment string of the ZipFile, in the szComment buffer.
+  uSizeBuf is the size of the szComment buffer.
+  return the number of byte copied or an error code <0
+*/
+extern int ZEXPORT unzGetGlobalComment (file, szComment, uSizeBuf)
+    unzFile file;
+    char *szComment;
+    uLong uSizeBuf;
+{
+    int err=UNZ_OK;
+    unz_s* s;
+    uLong uReadThis ;
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+
+    uReadThis = uSizeBuf;
+    if (uReadThis>s->gi.size_comment)
+        uReadThis = s->gi.size_comment;
+
+    if (ZSEEK(s->z_filefunc,s->filestream,s->central_pos+22,ZLIB_FILEFUNC_SEEK_SET)!=0)
+        return UNZ_ERRNO;
+
+    if (uReadThis>0)
+    {
+      *szComment='\0';
+      if (ZREAD(s->z_filefunc,s->filestream,szComment,uReadThis)!=uReadThis)
+        return UNZ_ERRNO;
+    }
+
+    if ((szComment != NULL) && (uSizeBuf > s->gi.size_comment))
+        *(szComment+s->gi.size_comment)='\0';
+    return (int)uReadThis;
+}
+
+/* Additions by RX '2004 */
+extern uLong ZEXPORT unzGetOffset (file)
+    unzFile file;
+{
+    unz_s* s;
+
+    if (file==NULL)
+          return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+    if (!s->current_file_ok)
+      return 0;
+    if (s->gi.number_entry != 0 && s->gi.number_entry != 0xffff)
+      if (s->num_file==s->gi.number_entry)
+         return 0;
+    return s->pos_in_central_dir;
+}
+
+extern int ZEXPORT unzSetOffset (file, pos)
+        unzFile file;
+        uLong pos;
+{
+    unz_s* s;
+    int err;
+
+    if (file==NULL)
+        return UNZ_PARAMERROR;
+    s=(unz_s*)file;
+
+    s->pos_in_central_dir = pos;
+    s->num_file = s->gi.number_entry;      /* hack */
+    err = unzlocal_GetCurrentFileInfoInternal(file,&s->cur_file_info,
+                                              &s->cur_file_info_internal,
+                                              NULL,0,NULL,0,NULL,0);
+    s->current_file_ok = (err == UNZ_OK);
+    return err;
+}
diff --git a/gs/zlib/contrib/minizip/unzip.h b/gs/zlib/contrib/minizip/unzip.h
new file mode 100644
index 000000000..b247937c8
--- /dev/null
+++ b/gs/zlib/contrib/minizip/unzip.h
@@ -0,0 +1,354 @@
+/* unzip.h -- IO for uncompress .zip files using zlib
+   Version 1.01e, February 12th, 2005
+
+   Copyright (C) 1998-2005 Gilles Vollant
+
+   This unzip package allow extract file from .ZIP file, compatible with PKZip 2.04g
+     WinZip, InfoZip tools and compatible.
+
+   Multi volume ZipFile (span) are not supported.
+   Encryption compatible with pkzip 2.04g only supported
+   Old compressions used by old PKZip 1.x are not supported
+
+
+   I WAIT FEEDBACK at mail info@winimage.com
+   Visit also http://www.winimage.com/zLibDll/unzip.htm for evolution
+
+   Condition of use and distribution are the same than zlib :
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+
+
+*/
+
+/* for more info about .ZIP format, see
+      http://www.info-zip.org/pub/infozip/doc/appnote-981119-iz.zip
+      http://www.info-zip.org/pub/infozip/doc/
+   PkWare has also a specification at :
+      ftp://ftp.pkware.com/probdesc.zip
+*/
+
+#ifndef _unz_H
+#define _unz_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef _ZLIB_H
+#include "zlib.h"
+#endif
+
+#ifndef _ZLIBIOAPI_H
+#include "ioapi.h"
+#endif
+
+#if defined(STRICTUNZIP) || defined(STRICTZIPUNZIP)
+/* like the STRICT of WIN32, we define a pointer that cannot be converted
+    from (void*) without cast */
+typedef struct TagunzFile__ { int unused; } unzFile__;
+typedef unzFile__ *unzFile;
+#else
+typedef voidp unzFile;
+#endif
+
+
+#define UNZ_OK                          (0)
+#define UNZ_END_OF_LIST_OF_FILE         (-100)
+#define UNZ_ERRNO                       (Z_ERRNO)
+#define UNZ_EOF                         (0)
+#define UNZ_PARAMERROR                  (-102)
+#define UNZ_BADZIPFILE                  (-103)
+#define UNZ_INTERNALERROR               (-104)
+#define UNZ_CRCERROR                    (-105)
+
+/* tm_unz contain date/time info */
+typedef struct tm_unz_s
+{
+    uInt tm_sec;            /* seconds after the minute - [0,59] */
+    uInt tm_min;            /* minutes after the hour - [0,59] */
+    uInt tm_hour;           /* hours since midnight - [0,23] */
+    uInt tm_mday;           /* day of the month - [1,31] */
+    uInt tm_mon;            /* months since January - [0,11] */
+    uInt tm_year;           /* years - [1980..2044] */
+} tm_unz;
+
+/* unz_global_info structure contain global data about the ZIPfile
+   These data comes from the end of central dir */
+typedef struct unz_global_info_s
+{
+    uLong number_entry;         /* total number of entries in
+                       the central dir on this disk */
+    uLong size_comment;         /* size of the global comment of the zipfile */
+} unz_global_info;
+
+
+/* unz_file_info contain information about a file in the zipfile */
+typedef struct unz_file_info_s
+{
+    uLong version;              /* version made by                 2 bytes */
+    uLong version_needed;       /* version needed to extract       2 bytes */
+    uLong flag;                 /* general purpose bit flag        2 bytes */
+    uLong compression_method;   /* compression method              2 bytes */
+    uLong dosDate;              /* last mod file date in Dos fmt   4 bytes */
+    uLong crc;                  /* crc-32                          4 bytes */
+    uLong compressed_size;      /* compressed size                 4 bytes */
+    uLong uncompressed_size;    /* uncompressed size               4 bytes */
+    uLong size_filename;        /* filename length                 2 bytes */
+    uLong size_file_extra;      /* extra field length              2 bytes */
+    uLong size_file_comment;    /* file comment length             2 bytes */
+
+    uLong disk_num_start;       /* disk number start               2 bytes */
+    uLong internal_fa;          /* internal file attributes        2 bytes */
+    uLong external_fa;          /* external file attributes        4 bytes */
+
+    tm_unz tmu_date;
+} unz_file_info;
+
+extern int ZEXPORT unzStringFileNameCompare OF ((const char* fileName1,
+                                                 const char* fileName2,
+                                                 int iCaseSensitivity));
+/*
+   Compare two filename (fileName1,fileName2).
+   If iCaseSenisivity = 1, comparision is case sensitivity (like strcmp)
+   If iCaseSenisivity = 2, comparision is not case sensitivity (like strcmpi
+                                or strcasecmp)
+   If iCaseSenisivity = 0, case sensitivity is defaut of your operating system
+    (like 1 on Unix, 2 on Windows)
+*/
+
+
+extern unzFile ZEXPORT unzOpen OF((const char *path));
+/*
+  Open a Zip file. path contain the full pathname (by example,
+     on a Windows XP computer "c:\\zlib\\zlib113.zip" or on an Unix computer
+     "zlib/zlib113.zip".
+     If the zipfile cannot be opened (file don't exist or in not valid), the
+       return value is NULL.
+     Else, the return value is a unzFile Handle, usable with other function
+       of this unzip package.
+*/
+
+extern unzFile ZEXPORT unzOpen2 OF((const char *path,
+                                    zlib_filefunc_def* pzlib_filefunc_def));
+/*
+   Open a Zip file, like unzOpen, but provide a set of file low level API
+      for read/write the zip file (see ioapi.h)
+*/
+
+extern int ZEXPORT unzClose OF((unzFile file));
+/*
+  Close a ZipFile opened with unzipOpen.
+  If there is files inside the .Zip opened with unzOpenCurrentFile (see later),
+    these files MUST be closed with unzipCloseCurrentFile before call unzipClose.
+  return UNZ_OK if there is no problem. */
+
+extern int ZEXPORT unzGetGlobalInfo OF((unzFile file,
+                                        unz_global_info *pglobal_info));
+/*
+  Write info about the ZipFile in the *pglobal_info structure.
+  No preparation of the structure is needed
+  return UNZ_OK if there is no problem. */
+
+
+extern int ZEXPORT unzGetGlobalComment OF((unzFile file,
+                                           char *szComment,
+                                           uLong uSizeBuf));
+/*
+  Get the global comment string of the ZipFile, in the szComment buffer.
+  uSizeBuf is the size of the szComment buffer.
+  return the number of byte copied or an error code <0
+*/
+
+
+/***************************************************************************/
+/* Unzip package allow you browse the directory of the zipfile */
+
+extern int ZEXPORT unzGoToFirstFile OF((unzFile file));
+/*
+  Set the current file of the zipfile to the first file.
+  return UNZ_OK if there is no problem
+*/
+
+extern int ZEXPORT unzGoToNextFile OF((unzFile file));
+/*
+  Set the current file of the zipfile to the next file.
+  return UNZ_OK if there is no problem
+  return UNZ_END_OF_LIST_OF_FILE if the actual file was the latest.
+*/
+
+extern int ZEXPORT unzLocateFile OF((unzFile file,
+                     const char *szFileName,
+                     int iCaseSensitivity));
+/*
+  Try locate the file szFileName in the zipfile.
+  For the iCaseSensitivity signification, see unzStringFileNameCompare
+
+  return value :
+  UNZ_OK if the file is found. It becomes the current file.
+  UNZ_END_OF_LIST_OF_FILE if the file is not found
+*/
+
+
+/* ****************************************** */
+/* Ryan supplied functions */
+/* unz_file_info contain information about a file in the zipfile */
+typedef struct unz_file_pos_s
+{
+    uLong pos_in_zip_directory;   /* offset in zip file directory */
+    uLong num_of_file;            /* # of file */
+} unz_file_pos;
+
+extern int ZEXPORT unzGetFilePos(
+    unzFile file,
+    unz_file_pos* file_pos);
+
+extern int ZEXPORT unzGoToFilePos(
+    unzFile file,
+    unz_file_pos* file_pos);
+
+/* ****************************************** */
+
+extern int ZEXPORT unzGetCurrentFileInfo OF((unzFile file,
+                         unz_file_info *pfile_info,
+                         char *szFileName,
+                         uLong fileNameBufferSize,
+                         void *extraField,
+                         uLong extraFieldBufferSize,
+                         char *szComment,
+                         uLong commentBufferSize));
+/*
+  Get Info about the current file
+  if pfile_info!=NULL, the *pfile_info structure will contain somes info about
+        the current file
+  if szFileName!=NULL, the filemane string will be copied in szFileName
+            (fileNameBufferSize is the size of the buffer)
+  if extraField!=NULL, the extra field information will be copied in extraField
+            (extraFieldBufferSize is the size of the buffer).
+            This is the Central-header version of the extra field
+  if szComment!=NULL, the comment string of the file will be copied in szComment
+            (commentBufferSize is the size of the buffer)
+*/
+
+/***************************************************************************/
+/* for reading the content of the current zipfile, you can open it, read data
+   from it, and close it (you can close it before reading all the file)
+   */
+
+extern int ZEXPORT unzOpenCurrentFile OF((unzFile file));
+/*
+  Open for reading data the current file in the zipfile.
+  If there is no error, the return value is UNZ_OK.
+*/
+
+extern int ZEXPORT unzOpenCurrentFilePassword OF((unzFile file,
+                                                  const char* password));
+/*
+  Open for reading data the current file in the zipfile.
+  password is a crypting password
+  If there is no error, the return value is UNZ_OK.
+*/
+
+extern int ZEXPORT unzOpenCurrentFile2 OF((unzFile file,
+                                           int* method,
+                                           int* level,
+                                           int raw));
+/*
+  Same than unzOpenCurrentFile, but open for read raw the file (not uncompress)
+    if raw==1
+  *method will receive method of compression, *level will receive level of
+     compression
+  note : you can set level parameter as NULL (if you did not want known level,
+         but you CANNOT set method parameter as NULL
+*/
+
+extern int ZEXPORT unzOpenCurrentFile3 OF((unzFile file,
+                                           int* method,
+                                           int* level,
+                                           int raw,
+                                           const char* password));
+/*
+  Same than unzOpenCurrentFile, but open for read raw the file (not uncompress)
+    if raw==1
+  *method will receive method of compression, *level will receive level of
+     compression
+  note : you can set level parameter as NULL (if you did not want known level,
+         but you CANNOT set method parameter as NULL
+*/
+
+
+extern int ZEXPORT unzCloseCurrentFile OF((unzFile file));
+/*
+  Close the file in zip opened with unzOpenCurrentFile
+  Return UNZ_CRCERROR if all the file was read but the CRC is not good
+*/
+
+extern int ZEXPORT unzReadCurrentFile OF((unzFile file,
+                      voidp buf,
+                      unsigned len));
+/*
+  Read bytes from the current file (opened by unzOpenCurrentFile)
+  buf contain buffer where data must be copied
+  len the size of buf.
+
+  return the number of byte copied if somes bytes are copied
+  return 0 if the end of file was reached
+  return <0 with error code if there is an error
+    (UNZ_ERRNO for IO error, or zLib error for uncompress error)
+*/
+
+extern z_off_t ZEXPORT unztell OF((unzFile file));
+/*
+  Give the current position in uncompressed data
+*/
+
+extern int ZEXPORT unzeof OF((unzFile file));
+/*
+  return 1 if the end of file was reached, 0 elsewhere
+*/
+
+extern int ZEXPORT unzGetLocalExtrafield OF((unzFile file,
+                                             voidp buf,
+                                             unsigned len));
+/*
+  Read extra field from the current file (opened by unzOpenCurrentFile)
+  This is the local-header version of the extra field (sometimes, there is
+    more info in the local-header version than in the central-header)
+
+  if buf==NULL, it return the size of the local extra field
+
+  if buf!=NULL, len is the size of the buffer, the extra header is copied in
+    buf.
+  the return value is the number of bytes copied in buf, or (if <0)
+    the error code
+*/
+
+/***************************************************************************/
+
+/* Get the current file offset */
+extern uLong ZEXPORT unzGetOffset (unzFile file);
+
+/* Set the current file offset */
+extern int ZEXPORT unzSetOffset (unzFile file, uLong pos);
+
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _unz_H */
diff --git a/gs/zlib/contrib/minizip/zip.c b/gs/zlib/contrib/minizip/zip.c
new file mode 100644
index 000000000..7fbe00274
--- /dev/null
+++ b/gs/zlib/contrib/minizip/zip.c
@@ -0,0 +1,1219 @@
+/* zip.c -- IO on .zip files using zlib
+   Version 1.01e, February 12th, 2005
+
+   27 Dec 2004 Rolf Kalbermatter
+   Modification to zipOpen2 to support globalComment retrieval.
+
+   Copyright (C) 1998-2005 Gilles Vollant
+
+   Read zip.h for more info
+*/
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include "zlib.h"
+#include "zip.h"
+
+#ifdef STDC
+#  include <stddef.h>
+#  include <string.h>
+#  include <stdlib.h>
+#endif
+#ifdef NO_ERRNO_H
+    extern int errno;
+#else
+#   include <errno.h>
+#endif
+
+
+#ifndef local
+#  define local static
+#endif
+/* compile with -Dlocal if your debugger can't find static symbols */
+
+#ifndef VERSIONMADEBY
+# define VERSIONMADEBY   (0x0) /* platform depedent */
+#endif
+
+#ifndef Z_BUFSIZE
+#define Z_BUFSIZE (16384)
+#endif
+
+#ifndef Z_MAXFILENAMEINZIP
+#define Z_MAXFILENAMEINZIP (256)
+#endif
+
+#ifndef ALLOC
+# define ALLOC(size) (malloc(size))
+#endif
+#ifndef TRYFREE
+# define TRYFREE(p) {if (p) free(p);}
+#endif
+
+/*
+#define SIZECENTRALDIRITEM (0x2e)
+#define SIZEZIPLOCALHEADER (0x1e)
+*/
+
+/* I've found an old Unix (a SunOS 4.1.3_U1) without all SEEK_* defined.... */
+
+#ifndef SEEK_CUR
+#define SEEK_CUR    1
+#endif
+
+#ifndef SEEK_END
+#define SEEK_END    2
+#endif
+
+#ifndef SEEK_SET
+#define SEEK_SET    0
+#endif
+
+#ifndef DEF_MEM_LEVEL
+#if MAX_MEM_LEVEL >= 8
+#  define DEF_MEM_LEVEL 8
+#else
+#  define DEF_MEM_LEVEL  MAX_MEM_LEVEL
+#endif
+#endif
+const char zip_copyright[] =
+   " zip 1.01 Copyright 1998-2004 Gilles Vollant - http://www.winimage.com/zLibDll";
+
+
+#define SIZEDATA_INDATABLOCK (4096-(4*4))
+
+#define LOCALHEADERMAGIC    (0x04034b50)
+#define CENTRALHEADERMAGIC  (0x02014b50)
+#define ENDHEADERMAGIC      (0x06054b50)
+
+#define FLAG_LOCALHEADER_OFFSET (0x06)
+#define CRC_LOCALHEADER_OFFSET  (0x0e)
+
+#define SIZECENTRALHEADER (0x2e) /* 46 */
+
+typedef struct linkedlist_datablock_internal_s
+{
+  struct linkedlist_datablock_internal_s* next_datablock;
+  uLong  avail_in_this_block;
+  uLong  filled_in_this_block;
+  uLong  unused; /* for future use and alignement */
+  unsigned char data[SIZEDATA_INDATABLOCK];
+} linkedlist_datablock_internal;
+
+typedef struct linkedlist_data_s
+{
+    linkedlist_datablock_internal* first_block;
+    linkedlist_datablock_internal* last_block;
+} linkedlist_data;
+
+
+typedef struct
+{
+    z_stream stream;            /* zLib stream structure for inflate */
+    int  stream_initialised;    /* 1 is stream is initialised */
+    uInt pos_in_buffered_data;  /* last written byte in buffered_data */
+
+    uLong pos_local_header;     /* offset of the local header of the file
+                                     currenty writing */
+    char* central_header;       /* central header data for the current file */
+    uLong size_centralheader;   /* size of the central header for cur file */
+    uLong flag;                 /* flag of the file currently writing */
+
+    int  method;                /* compression method of file currenty wr.*/
+    int  raw;                   /* 1 for directly writing raw data */
+    Byte buffered_data[Z_BUFSIZE];/* buffer contain compressed data to be writ*/
+    uLong dosDate;
+    uLong crc32;
+    int  encrypt;
+#ifndef NOCRYPT
+    unsigned long keys[3];     /* keys defining the pseudo-random sequence */
+    const unsigned long* pcrc_32_tab;
+    int crypt_header_size;
+#endif
+} curfile_info;
+
+typedef struct
+{
+    zlib_filefunc_def z_filefunc;
+    voidpf filestream;        /* io structore of the zipfile */
+    linkedlist_data central_dir;/* datablock with central dir in construction*/
+    int  in_opened_file_inzip;  /* 1 if a file in the zip is currently writ.*/
+    curfile_info ci;            /* info on the file curretly writing */
+
+    uLong begin_pos;            /* position of the beginning of the zipfile */
+    uLong add_position_when_writting_offset;
+    uLong number_entry;
+#ifndef NO_ADDFILEINEXISTINGZIP
+    char *globalcomment;
+#endif
+} zip_internal;
+
+
+
+#ifndef NOCRYPT
+#define INCLUDECRYPTINGCODE_IFCRYPTALLOWED
+#include "crypt.h"
+#endif
+
+local linkedlist_datablock_internal* allocate_new_datablock()
+{
+    linkedlist_datablock_internal* ldi;
+    ldi = (linkedlist_datablock_internal*)
+                 ALLOC(sizeof(linkedlist_datablock_internal));
+    if (ldi!=NULL)
+    {
+        ldi->next_datablock = NULL ;
+        ldi->filled_in_this_block = 0 ;
+        ldi->avail_in_this_block = SIZEDATA_INDATABLOCK ;
+    }
+    return ldi;
+}
+
+local void free_datablock(ldi)
+    linkedlist_datablock_internal* ldi;
+{
+    while (ldi!=NULL)
+    {
+        linkedlist_datablock_internal* ldinext = ldi->next_datablock;
+        TRYFREE(ldi);
+        ldi = ldinext;
+    }
+}
+
+local void init_linkedlist(ll)
+    linkedlist_data* ll;
+{
+    ll->first_block = ll->last_block = NULL;
+}
+
+local void free_linkedlist(ll)
+    linkedlist_data* ll;
+{
+    free_datablock(ll->first_block);
+    ll->first_block = ll->last_block = NULL;
+}
+
+
+local int add_data_in_datablock(ll,buf,len)
+    linkedlist_data* ll;
+    const void* buf;
+    uLong len;
+{
+    linkedlist_datablock_internal* ldi;
+    const unsigned char* from_copy;
+
+    if (ll==NULL)
+        return ZIP_INTERNALERROR;
+
+    if (ll->last_block == NULL)
+    {
+        ll->first_block = ll->last_block = allocate_new_datablock();
+        if (ll->first_block == NULL)
+            return ZIP_INTERNALERROR;
+    }
+
+    ldi = ll->last_block;
+    from_copy = (unsigned char*)buf;
+
+    while (len>0)
+    {
+        uInt copy_this;
+        uInt i;
+        unsigned char* to_copy;
+
+        if (ldi->avail_in_this_block==0)
+        {
+            ldi->next_datablock = allocate_new_datablock();
+            if (ldi->next_datablock == NULL)
+                return ZIP_INTERNALERROR;
+            ldi = ldi->next_datablock ;
+            ll->last_block = ldi;
+        }
+
+        if (ldi->avail_in_this_block < len)
+            copy_this = (uInt)ldi->avail_in_this_block;
+        else
+            copy_this = (uInt)len;
+
+        to_copy = &(ldi->data[ldi->filled_in_this_block]);
+
+        for (i=0;i<copy_this;i++)
+            *(to_copy+i)=*(from_copy+i);
+
+        ldi->filled_in_this_block += copy_this;
+        ldi->avail_in_this_block -= copy_this;
+        from_copy += copy_this ;
+        len -= copy_this;
+    }
+    return ZIP_OK;
+}
+
+
+
+/****************************************************************************/
+
+#ifndef NO_ADDFILEINEXISTINGZIP
+/* ===========================================================================
+   Inputs a long in LSB order to the given file
+   nbByte == 1, 2 or 4 (byte, short or long)
+*/
+
+local int ziplocal_putValue OF((const zlib_filefunc_def* pzlib_filefunc_def,
+                                voidpf filestream, uLong x, int nbByte));
+local int ziplocal_putValue (pzlib_filefunc_def, filestream, x, nbByte)
+    const zlib_filefunc_def* pzlib_filefunc_def;
+    voidpf filestream;
+    uLong x;
+    int nbByte;
+{
+    unsigned char buf[4];
+    int n;
+    for (n = 0; n < nbByte; n++)
+    {
+        buf[n] = (unsigned char)(x & 0xff);
+        x >>= 8;
+    }
+    if (x != 0)
+      {     /* data overflow - hack for ZIP64 (X Roche) */
+      for (n = 0; n < nbByte; n++)
+        {
+          buf[n] = 0xff;
+        }
+      }
+
+    if (ZWRITE(*pzlib_filefunc_def,filestream,buf,nbByte)!=(uLong)nbByte)
+        return ZIP_ERRNO;
+    else
+        return ZIP_OK;
+}
+
+local void ziplocal_putValue_inmemory OF((void* dest, uLong x, int nbByte));
+local void ziplocal_putValue_inmemory (dest, x, nbByte)
+    void* dest;
+    uLong x;
+    int nbByte;
+{
+    unsigned char* buf=(unsigned char*)dest;
+    int n;
+    for (n = 0; n < nbByte; n++) {
+        buf[n] = (unsigned char)(x & 0xff);
+        x >>= 8;
+    }
+
+    if (x != 0)
+    {     /* data overflow - hack for ZIP64 */
+       for (n = 0; n < nbByte; n++)
+       {
+          buf[n] = 0xff;
+       }
+    }
+}
+
+/****************************************************************************/
+
+
+local uLong ziplocal_TmzDateToDosDate(ptm,dosDate)
+    const tm_zip* ptm;
+    uLong dosDate;
+{
+    uLong year = (uLong)ptm->tm_year;
+    if (year>1980)
+        year-=1980;
+    else if (year>80)
+        year-=80;
+    return
+      (uLong) (((ptm->tm_mday) + (32 * (ptm->tm_mon+1)) + (512 * year)) << 16) |
+        ((ptm->tm_sec/2) + (32* ptm->tm_min) + (2048 * (uLong)ptm->tm_hour));
+}
+
+
+/****************************************************************************/
+
+local int ziplocal_getByte OF((
+    const zlib_filefunc_def* pzlib_filefunc_def,
+    voidpf filestream,
+    int *pi));
+
+local int ziplocal_getByte(pzlib_filefunc_def,filestream,pi)
+    const zlib_filefunc_def* pzlib_filefunc_def;
+    voidpf filestream;
+    int *pi;
+{
+    unsigned char c;
+    int err = (int)ZREAD(*pzlib_filefunc_def,filestream,&c,1);
+    if (err==1)
+    {
+        *pi = (int)c;
+        return ZIP_OK;
+    }
+    else
+    {
+        if (ZERROR(*pzlib_filefunc_def,filestream))
+            return ZIP_ERRNO;
+        else
+            return ZIP_EOF;
+    }
+}
+
+
+/* ===========================================================================
+   Reads a long in LSB order from the given gz_stream. Sets
+*/
+local int ziplocal_getShort OF((
+    const zlib_filefunc_def* pzlib_filefunc_def,
+    voidpf filestream,
+    uLong *pX));
+
+local int ziplocal_getShort (pzlib_filefunc_def,filestream,pX)
+    const zlib_filefunc_def* pzlib_filefunc_def;
+    voidpf filestream;
+    uLong *pX;
+{
+    uLong x ;
+    int i;
+    int err;
+
+    err = ziplocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x = (uLong)i;
+
+    if (err==ZIP_OK)
+        err = ziplocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x += ((uLong)i)<<8;
+
+    if (err==ZIP_OK)
+        *pX = x;
+    else
+        *pX = 0;
+    return err;
+}
+
+local int ziplocal_getLong OF((
+    const zlib_filefunc_def* pzlib_filefunc_def,
+    voidpf filestream,
+    uLong *pX));
+
+local int ziplocal_getLong (pzlib_filefunc_def,filestream,pX)
+    const zlib_filefunc_def* pzlib_filefunc_def;
+    voidpf filestream;
+    uLong *pX;
+{
+    uLong x ;
+    int i;
+    int err;
+
+    err = ziplocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x = (uLong)i;
+
+    if (err==ZIP_OK)
+        err = ziplocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x += ((uLong)i)<<8;
+
+    if (err==ZIP_OK)
+        err = ziplocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x += ((uLong)i)<<16;
+
+    if (err==ZIP_OK)
+        err = ziplocal_getByte(pzlib_filefunc_def,filestream,&i);
+    x += ((uLong)i)<<24;
+
+    if (err==ZIP_OK)
+        *pX = x;
+    else
+        *pX = 0;
+    return err;
+}
+
+#ifndef BUFREADCOMMENT
+#define BUFREADCOMMENT (0x400)
+#endif
+/*
+  Locate the Central directory of a zipfile (at the end, just before
+    the global comment)
+*/
+local uLong ziplocal_SearchCentralDir OF((
+    const zlib_filefunc_def* pzlib_filefunc_def,
+    voidpf filestream));
+
+local uLong ziplocal_SearchCentralDir(pzlib_filefunc_def,filestream)
+    const zlib_filefunc_def* pzlib_filefunc_def;
+    voidpf filestream;
+{
+    unsigned char* buf;
+    uLong uSizeFile;
+    uLong uBackRead;
+    uLong uMaxBack=0xffff; /* maximum size of global comment */
+    uLong uPosFound=0;
+
+    if (ZSEEK(*pzlib_filefunc_def,filestream,0,ZLIB_FILEFUNC_SEEK_END) != 0)
+        return 0;
+
+
+    uSizeFile = ZTELL(*pzlib_filefunc_def,filestream);
+
+    if (uMaxBack>uSizeFile)
+        uMaxBack = uSizeFile;
+
+    buf = (unsigned char*)ALLOC(BUFREADCOMMENT+4);
+    if (buf==NULL)
+        return 0;
+
+    uBackRead = 4;
+    while (uBackRead<uMaxBack)
+    {
+        uLong uReadSize,uReadPos ;
+        int i;
+        if (uBackRead+BUFREADCOMMENT>uMaxBack)
+            uBackRead = uMaxBack;
+        else
+            uBackRead+=BUFREADCOMMENT;
+        uReadPos = uSizeFile-uBackRead ;
+
+        uReadSize = ((BUFREADCOMMENT+4) < (uSizeFile-uReadPos)) ?
+                     (BUFREADCOMMENT+4) : (uSizeFile-uReadPos);
+        if (ZSEEK(*pzlib_filefunc_def,filestream,uReadPos,ZLIB_FILEFUNC_SEEK_SET)!=0)
+            break;
+
+        if (ZREAD(*pzlib_filefunc_def,filestream,buf,uReadSize)!=uReadSize)
+            break;
+
+        for (i=(int)uReadSize-3; (i--)>0;)
+            if (((*(buf+i))==0x50) && ((*(buf+i+1))==0x4b) &&
+                ((*(buf+i+2))==0x05) && ((*(buf+i+3))==0x06))
+            {
+                uPosFound = uReadPos+i;
+                break;
+            }
+
+        if (uPosFound!=0)
+            break;
+    }
+    TRYFREE(buf);
+    return uPosFound;
+}
+#endif /* !NO_ADDFILEINEXISTINGZIP*/
+
+/************************************************************/
+extern zipFile ZEXPORT zipOpen2 (pathname, append, globalcomment, pzlib_filefunc_def)
+    const char *pathname;
+    int append;
+    zipcharpc* globalcomment;
+    zlib_filefunc_def* pzlib_filefunc_def;
+{
+    zip_internal ziinit;
+    zip_internal* zi;
+    int err=ZIP_OK;
+
+
+    if (pzlib_filefunc_def==NULL)
+        fill_fopen_filefunc(&ziinit.z_filefunc);
+    else
+        ziinit.z_filefunc = *pzlib_filefunc_def;
+
+    ziinit.filestream = (*(ziinit.z_filefunc.zopen_file))
+                 (ziinit.z_filefunc.opaque,
+                  pathname,
+                  (append == APPEND_STATUS_CREATE) ?
+                  (ZLIB_FILEFUNC_MODE_READ | ZLIB_FILEFUNC_MODE_WRITE | ZLIB_FILEFUNC_MODE_CREATE) :
+                    (ZLIB_FILEFUNC_MODE_READ | ZLIB_FILEFUNC_MODE_WRITE | ZLIB_FILEFUNC_MODE_EXISTING));
+
+    if (ziinit.filestream == NULL)
+        return NULL;
+    ziinit.begin_pos = ZTELL(ziinit.z_filefunc,ziinit.filestream);
+    ziinit.in_opened_file_inzip = 0;
+    ziinit.ci.stream_initialised = 0;
+    ziinit.number_entry = 0;
+    ziinit.add_position_when_writting_offset = 0;
+    init_linkedlist(&(ziinit.central_dir));
+
+
+    zi = (zip_internal*)ALLOC(sizeof(zip_internal));
+    if (zi==NULL)
+    {
+        ZCLOSE(ziinit.z_filefunc,ziinit.filestream);
+        return NULL;
+    }
+
+    /* now we add file in a zipfile */
+#    ifndef NO_ADDFILEINEXISTINGZIP
+    ziinit.globalcomment = NULL;
+    if (append == APPEND_STATUS_ADDINZIP)
+    {
+        uLong byte_before_the_zipfile;/* byte before the zipfile, (>0 for sfx)*/
+
+        uLong size_central_dir;     /* size of the central directory  */
+        uLong offset_central_dir;   /* offset of start of central directory */
+        uLong central_pos,uL;
+
+        uLong number_disk;          /* number of the current dist, used for
+                                    spaning ZIP, unsupported, always 0*/
+        uLong number_disk_with_CD;  /* number the the disk with central dir, used
+                                    for spaning ZIP, unsupported, always 0*/
+        uLong number_entry;
+        uLong number_entry_CD;      /* total number of entries in
+                                    the central dir
+                                    (same than number_entry on nospan) */
+        uLong size_comment;
+
+        central_pos = ziplocal_SearchCentralDir(&ziinit.z_filefunc,ziinit.filestream);
+        if (central_pos==0)
+            err=ZIP_ERRNO;
+
+        if (ZSEEK(ziinit.z_filefunc, ziinit.filestream,
+                                        central_pos,ZLIB_FILEFUNC_SEEK_SET)!=0)
+            err=ZIP_ERRNO;
+
+        /* the signature, already checked */
+        if (ziplocal_getLong(&ziinit.z_filefunc, ziinit.filestream,&uL)!=ZIP_OK)
+            err=ZIP_ERRNO;
+
+        /* number of this disk */
+        if (ziplocal_getShort(&ziinit.z_filefunc, ziinit.filestream,&number_disk)!=ZIP_OK)
+            err=ZIP_ERRNO;
+
+        /* number of the disk with the start of the central directory */
+        if (ziplocal_getShort(&ziinit.z_filefunc, ziinit.filestream,&number_disk_with_CD)!=ZIP_OK)
+            err=ZIP_ERRNO;
+
+        /* total number of entries in the central dir on this disk */
+        if (ziplocal_getShort(&ziinit.z_filefunc, ziinit.filestream,&number_entry)!=ZIP_OK)
+            err=ZIP_ERRNO;
+
+        /* total number of entries in the central dir */
+        if (ziplocal_getShort(&ziinit.z_filefunc, ziinit.filestream,&number_entry_CD)!=ZIP_OK)
+            err=ZIP_ERRNO;
+
+        if ((number_entry_CD!=number_entry) ||
+            (number_disk_with_CD!=0) ||
+            (number_disk!=0))
+            err=ZIP_BADZIPFILE;
+
+        /* size of the central directory */
+        if (ziplocal_getLong(&ziinit.z_filefunc, ziinit.filestream,&size_central_dir)!=ZIP_OK)
+            err=ZIP_ERRNO;
+
+        /* offset of start of central directory with respect to the
+            starting disk number */
+        if (ziplocal_getLong(&ziinit.z_filefunc, ziinit.filestream,&offset_central_dir)!=ZIP_OK)
+            err=ZIP_ERRNO;
+
+        /* zipfile global comment length */
+        if (ziplocal_getShort(&ziinit.z_filefunc, ziinit.filestream,&size_comment)!=ZIP_OK)
+            err=ZIP_ERRNO;
+
+        if ((central_pos<offset_central_dir+size_central_dir) &&
+            (err==ZIP_OK))
+            err=ZIP_BADZIPFILE;
+
+        if (err!=ZIP_OK)
+        {
+            ZCLOSE(ziinit.z_filefunc, ziinit.filestream);
+            return NULL;
+        }
+
+        if (size_comment>0)
+        {
+            ziinit.globalcomment = ALLOC(size_comment+1);
+            if (ziinit.globalcomment)
+            {
+               size_comment = ZREAD(ziinit.z_filefunc, ziinit.filestream,ziinit.globalcomment,size_comment);
+               ziinit.globalcomment[size_comment]=0;
+            }
+        }
+
+        byte_before_the_zipfile = central_pos -
+                                (offset_central_dir+size_central_dir);
+        ziinit.add_position_when_writting_offset = byte_before_the_zipfile;
+
+        {
+            uLong size_central_dir_to_read = size_central_dir;
+            size_t buf_size = SIZEDATA_INDATABLOCK;
+            void* buf_read = (void*)ALLOC(buf_size);
+            if (ZSEEK(ziinit.z_filefunc, ziinit.filestream,
+                  offset_central_dir + byte_before_the_zipfile,
+                  ZLIB_FILEFUNC_SEEK_SET) != 0)
+                  err=ZIP_ERRNO;
+
+            while ((size_central_dir_to_read>0) && (err==ZIP_OK))
+            {
+                uLong read_this = SIZEDATA_INDATABLOCK;
+                if (read_this > size_central_dir_to_read)
+                    read_this = size_central_dir_to_read;
+                if (ZREAD(ziinit.z_filefunc, ziinit.filestream,buf_read,read_this) != read_this)
+                    err=ZIP_ERRNO;
+
+                if (err==ZIP_OK)
+                    err = add_data_in_datablock(&ziinit.central_dir,buf_read,
+                                                (uLong)read_this);
+                size_central_dir_to_read-=read_this;
+            }
+            TRYFREE(buf_read);
+        }
+        ziinit.begin_pos = byte_before_the_zipfile;
+        ziinit.number_entry = number_entry_CD;
+
+        if (ZSEEK(ziinit.z_filefunc, ziinit.filestream,
+                  offset_central_dir+byte_before_the_zipfile,ZLIB_FILEFUNC_SEEK_SET)!=0)
+            err=ZIP_ERRNO;
+    }
+
+    if (globalcomment)
+    {
+      *globalcomment = ziinit.globalcomment;
+    }
+#    endif /* !NO_ADDFILEINEXISTINGZIP*/
+
+    if (err != ZIP_OK)
+    {
+#    ifndef NO_ADDFILEINEXISTINGZIP
+        TRYFREE(ziinit.globalcomment);
+#    endif /* !NO_ADDFILEINEXISTINGZIP*/
+        TRYFREE(zi);
+        return NULL;
+    }
+    else
+    {
+        *zi = ziinit;
+        return (zipFile)zi;
+    }
+}
+
+extern zipFile ZEXPORT zipOpen (pathname, append)
+    const char *pathname;
+    int append;
+{
+    return zipOpen2(pathname,append,NULL,NULL);
+}
+
+extern int ZEXPORT zipOpenNewFileInZip3 (file, filename, zipfi,
+                                         extrafield_local, size_extrafield_local,
+                                         extrafield_global, size_extrafield_global,
+                                         comment, method, level, raw,
+                                         windowBits, memLevel, strategy,
+                                         password, crcForCrypting)
+    zipFile file;
+    const char* filename;
+    const zip_fileinfo* zipfi;
+    const void* extrafield_local;
+    uInt size_extrafield_local;
+    const void* extrafield_global;
+    uInt size_extrafield_global;
+    const char* comment;
+    int method;
+    int level;
+    int raw;
+    int windowBits;
+    int memLevel;
+    int strategy;
+    const char* password;
+    uLong crcForCrypting;
+{
+    zip_internal* zi;
+    uInt size_filename;
+    uInt size_comment;
+    uInt i;
+    int err = ZIP_OK;
+
+#    ifdef NOCRYPT
+    if (password != NULL)
+        return ZIP_PARAMERROR;
+#    endif
+
+    if (file == NULL)
+        return ZIP_PARAMERROR;
+    if ((method!=0) && (method!=Z_DEFLATED))
+        return ZIP_PARAMERROR;
+
+    zi = (zip_internal*)file;
+
+    if (zi->in_opened_file_inzip == 1)
+    {
+        err = zipCloseFileInZip (file);
+        if (err != ZIP_OK)
+            return err;
+    }
+
+
+    if (filename==NULL)
+        filename="-";
+
+    if (comment==NULL)
+        size_comment = 0;
+    else
+        size_comment = (uInt)strlen(comment);
+
+    size_filename = (uInt)strlen(filename);
+
+    if (zipfi == NULL)
+        zi->ci.dosDate = 0;
+    else
+    {
+        if (zipfi->dosDate != 0)
+            zi->ci.dosDate = zipfi->dosDate;
+        else zi->ci.dosDate = ziplocal_TmzDateToDosDate(&zipfi->tmz_date,zipfi->dosDate);
+    }
+
+    zi->ci.flag = 0;
+    if ((level==8) || (level==9))
+      zi->ci.flag |= 2;
+    if ((level==2))
+      zi->ci.flag |= 4;
+    if ((level==1))
+      zi->ci.flag |= 6;
+    if (password != NULL)
+      zi->ci.flag |= 1;
+
+    zi->ci.crc32 = 0;
+    zi->ci.method = method;
+    zi->ci.encrypt = 0;
+    zi->ci.stream_initialised = 0;
+    zi->ci.pos_in_buffered_data = 0;
+    zi->ci.raw = raw;
+    zi->ci.pos_local_header = ZTELL(zi->z_filefunc,zi->filestream) ;
+    zi->ci.size_centralheader = SIZECENTRALHEADER + size_filename +
+                                      size_extrafield_global + size_comment;
+    zi->ci.central_header = (char*)ALLOC((uInt)zi->ci.size_centralheader);
+
+    ziplocal_putValue_inmemory(zi->ci.central_header,(uLong)CENTRALHEADERMAGIC,4);
+    /* version info */
+    ziplocal_putValue_inmemory(zi->ci.central_header+4,(uLong)VERSIONMADEBY,2);
+    ziplocal_putValue_inmemory(zi->ci.central_header+6,(uLong)20,2);
+    ziplocal_putValue_inmemory(zi->ci.central_header+8,(uLong)zi->ci.flag,2);
+    ziplocal_putValue_inmemory(zi->ci.central_header+10,(uLong)zi->ci.method,2);
+    ziplocal_putValue_inmemory(zi->ci.central_header+12,(uLong)zi->ci.dosDate,4);
+    ziplocal_putValue_inmemory(zi->ci.central_header+16,(uLong)0,4); /*crc*/
+    ziplocal_putValue_inmemory(zi->ci.central_header+20,(uLong)0,4); /*compr size*/
+    ziplocal_putValue_inmemory(zi->ci.central_header+24,(uLong)0,4); /*uncompr size*/
+    ziplocal_putValue_inmemory(zi->ci.central_header+28,(uLong)size_filename,2);
+    ziplocal_putValue_inmemory(zi->ci.central_header+30,(uLong)size_extrafield_global,2);
+    ziplocal_putValue_inmemory(zi->ci.central_header+32,(uLong)size_comment,2);
+    ziplocal_putValue_inmemory(zi->ci.central_header+34,(uLong)0,2); /*disk nm start*/
+
+    if (zipfi==NULL)
+        ziplocal_putValue_inmemory(zi->ci.central_header+36,(uLong)0,2);
+    else
+        ziplocal_putValue_inmemory(zi->ci.central_header+36,(uLong)zipfi->internal_fa,2);
+
+    if (zipfi==NULL)
+        ziplocal_putValue_inmemory(zi->ci.central_header+38,(uLong)0,4);
+    else
+        ziplocal_putValue_inmemory(zi->ci.central_header+38,(uLong)zipfi->external_fa,4);
+
+    ziplocal_putValue_inmemory(zi->ci.central_header+42,(uLong)zi->ci.pos_local_header- zi->add_position_when_writting_offset,4);
+
+    for (i=0;i<size_filename;i++)
+        *(zi->ci.central_header+SIZECENTRALHEADER+i) = *(filename+i);
+
+    for (i=0;i<size_extrafield_global;i++)
+        *(zi->ci.central_header+SIZECENTRALHEADER+size_filename+i) =
+              *(((const char*)extrafield_global)+i);
+
+    for (i=0;i<size_comment;i++)
+        *(zi->ci.central_header+SIZECENTRALHEADER+size_filename+
+              size_extrafield_global+i) = *(comment+i);
+    if (zi->ci.central_header == NULL)
+        return ZIP_INTERNALERROR;
+
+    /* write the local header */
+    err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)LOCALHEADERMAGIC,4);
+
+    if (err==ZIP_OK)
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)20,2);/* version needed to extract */
+    if (err==ZIP_OK)
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)zi->ci.flag,2);
+
+    if (err==ZIP_OK)
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)zi->ci.method,2);
+
+    if (err==ZIP_OK)
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)zi->ci.dosDate,4);
+
+    if (err==ZIP_OK)
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)0,4); /* crc 32, unknown */
+    if (err==ZIP_OK)
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)0,4); /* compressed size, unknown */
+    if (err==ZIP_OK)
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)0,4); /* uncompressed size, unknown */
+
+    if (err==ZIP_OK)
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)size_filename,2);
+
+    if (err==ZIP_OK)
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)size_extrafield_local,2);
+
+    if ((err==ZIP_OK) && (size_filename>0))
+        if (ZWRITE(zi->z_filefunc,zi->filestream,filename,size_filename)!=size_filename)
+                err = ZIP_ERRNO;
+
+    if ((err==ZIP_OK) && (size_extrafield_local>0))
+        if (ZWRITE(zi->z_filefunc,zi->filestream,extrafield_local,size_extrafield_local)
+                                                                           !=size_extrafield_local)
+                err = ZIP_ERRNO;
+
+    zi->ci.stream.avail_in = (uInt)0;
+    zi->ci.stream.avail_out = (uInt)Z_BUFSIZE;
+    zi->ci.stream.next_out = zi->ci.buffered_data;
+    zi->ci.stream.total_in = 0;
+    zi->ci.stream.total_out = 0;
+
+    if ((err==ZIP_OK) && (zi->ci.method == Z_DEFLATED) && (!zi->ci.raw))
+    {
+        zi->ci.stream.zalloc = (alloc_func)0;
+        zi->ci.stream.zfree = (free_func)0;
+        zi->ci.stream.opaque = (voidpf)0;
+
+        if (windowBits>0)
+            windowBits = -windowBits;
+
+        err = deflateInit2(&zi->ci.stream, level,
+               Z_DEFLATED, windowBits, memLevel, strategy);
+
+        if (err==Z_OK)
+            zi->ci.stream_initialised = 1;
+    }
+#    ifndef NOCRYPT
+    zi->ci.crypt_header_size = 0;
+    if ((err==Z_OK) && (password != NULL))
+    {
+        unsigned char bufHead[RAND_HEAD_LEN];
+        unsigned int sizeHead;
+        zi->ci.encrypt = 1;
+        zi->ci.pcrc_32_tab = get_crc_table();
+        /*init_keys(password,zi->ci.keys,zi->ci.pcrc_32_tab);*/
+
+        sizeHead=crypthead(password,bufHead,RAND_HEAD_LEN,zi->ci.keys,zi->ci.pcrc_32_tab,crcForCrypting);
+        zi->ci.crypt_header_size = sizeHead;
+
+        if (ZWRITE(zi->z_filefunc,zi->filestream,bufHead,sizeHead) != sizeHead)
+                err = ZIP_ERRNO;
+    }
+#    endif
+
+    if (err==Z_OK)
+        zi->in_opened_file_inzip = 1;
+    return err;
+}
+
+extern int ZEXPORT zipOpenNewFileInZip2(file, filename, zipfi,
+                                        extrafield_local, size_extrafield_local,
+                                        extrafield_global, size_extrafield_global,
+                                        comment, method, level, raw)
+    zipFile file;
+    const char* filename;
+    const zip_fileinfo* zipfi;
+    const void* extrafield_local;
+    uInt size_extrafield_local;
+    const void* extrafield_global;
+    uInt size_extrafield_global;
+    const char* comment;
+    int method;
+    int level;
+    int raw;
+{
+    return zipOpenNewFileInZip3 (file, filename, zipfi,
+                                 extrafield_local, size_extrafield_local,
+                                 extrafield_global, size_extrafield_global,
+                                 comment, method, level, raw,
+                                 -MAX_WBITS, DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY,
+                                 NULL, 0);
+}
+
+extern int ZEXPORT zipOpenNewFileInZip (file, filename, zipfi,
+                                        extrafield_local, size_extrafield_local,
+                                        extrafield_global, size_extrafield_global,
+                                        comment, method, level)
+    zipFile file;
+    const char* filename;
+    const zip_fileinfo* zipfi;
+    const void* extrafield_local;
+    uInt size_extrafield_local;
+    const void* extrafield_global;
+    uInt size_extrafield_global;
+    const char* comment;
+    int method;
+    int level;
+{
+    return zipOpenNewFileInZip2 (file, filename, zipfi,
+                                 extrafield_local, size_extrafield_local,
+                                 extrafield_global, size_extrafield_global,
+                                 comment, method, level, 0);
+}
+
+local int zipFlushWriteBuffer(zi)
+  zip_internal* zi;
+{
+    int err=ZIP_OK;
+
+    if (zi->ci.encrypt != 0)
+    {
+#ifndef NOCRYPT
+        uInt i;
+        int t;
+        for (i=0;i<zi->ci.pos_in_buffered_data;i++)
+            zi->ci.buffered_data[i] = zencode(zi->ci.keys, zi->ci.pcrc_32_tab,
+                                       zi->ci.buffered_data[i],t);
+#endif
+    }
+    if (ZWRITE(zi->z_filefunc,zi->filestream,zi->ci.buffered_data,zi->ci.pos_in_buffered_data)
+                                                                    !=zi->ci.pos_in_buffered_data)
+      err = ZIP_ERRNO;
+    zi->ci.pos_in_buffered_data = 0;
+    return err;
+}
+
+extern int ZEXPORT zipWriteInFileInZip (file, buf, len)
+    zipFile file;
+    const void* buf;
+    unsigned len;
+{
+    zip_internal* zi;
+    int err=ZIP_OK;
+
+    if (file == NULL)
+        return ZIP_PARAMERROR;
+    zi = (zip_internal*)file;
+
+    if (zi->in_opened_file_inzip == 0)
+        return ZIP_PARAMERROR;
+
+    zi->ci.stream.next_in = (void*)buf;
+    zi->ci.stream.avail_in = len;
+    zi->ci.crc32 = crc32(zi->ci.crc32,buf,len);
+
+    while ((err==ZIP_OK) && (zi->ci.stream.avail_in>0))
+    {
+        if (zi->ci.stream.avail_out == 0)
+        {
+            if (zipFlushWriteBuffer(zi) == ZIP_ERRNO)
+                err = ZIP_ERRNO;
+            zi->ci.stream.avail_out = (uInt)Z_BUFSIZE;
+            zi->ci.stream.next_out = zi->ci.buffered_data;
+        }
+
+
+        if(err != ZIP_OK)
+            break;
+
+        if ((zi->ci.method == Z_DEFLATED) && (!zi->ci.raw))
+        {
+            uLong uTotalOutBefore = zi->ci.stream.total_out;
+            err=deflate(&zi->ci.stream,  Z_NO_FLUSH);
+            zi->ci.pos_in_buffered_data += (uInt)(zi->ci.stream.total_out - uTotalOutBefore) ;
+
+        }
+        else
+        {
+            uInt copy_this,i;
+            if (zi->ci.stream.avail_in < zi->ci.stream.avail_out)
+                copy_this = zi->ci.stream.avail_in;
+            else
+                copy_this = zi->ci.stream.avail_out;
+            for (i=0;i<copy_this;i++)
+                *(((char*)zi->ci.stream.next_out)+i) =
+                    *(((const char*)zi->ci.stream.next_in)+i);
+            {
+                zi->ci.stream.avail_in -= copy_this;
+                zi->ci.stream.avail_out-= copy_this;
+                zi->ci.stream.next_in+= copy_this;
+                zi->ci.stream.next_out+= copy_this;
+                zi->ci.stream.total_in+= copy_this;
+                zi->ci.stream.total_out+= copy_this;
+                zi->ci.pos_in_buffered_data += copy_this;
+            }
+        }
+    }
+
+    return err;
+}
+
+extern int ZEXPORT zipCloseFileInZipRaw (file, uncompressed_size, crc32)
+    zipFile file;
+    uLong uncompressed_size;
+    uLong crc32;
+{
+    zip_internal* zi;
+    uLong compressed_size;
+    int err=ZIP_OK;
+
+    if (file == NULL)
+        return ZIP_PARAMERROR;
+    zi = (zip_internal*)file;
+
+    if (zi->in_opened_file_inzip == 0)
+        return ZIP_PARAMERROR;
+    zi->ci.stream.avail_in = 0;
+
+    if ((zi->ci.method == Z_DEFLATED) && (!zi->ci.raw))
+        while (err==ZIP_OK)
+    {
+        uLong uTotalOutBefore;
+        if (zi->ci.stream.avail_out == 0)
+        {
+            if (zipFlushWriteBuffer(zi) == ZIP_ERRNO)
+                err = ZIP_ERRNO;
+            zi->ci.stream.avail_out = (uInt)Z_BUFSIZE;
+            zi->ci.stream.next_out = zi->ci.buffered_data;
+        }
+        uTotalOutBefore = zi->ci.stream.total_out;
+        err=deflate(&zi->ci.stream,  Z_FINISH);
+        zi->ci.pos_in_buffered_data += (uInt)(zi->ci.stream.total_out - uTotalOutBefore) ;
+    }
+
+    if (err==Z_STREAM_END)
+        err=ZIP_OK; /* this is normal */
+
+    if ((zi->ci.pos_in_buffered_data>0) && (err==ZIP_OK))
+        if (zipFlushWriteBuffer(zi)==ZIP_ERRNO)
+            err = ZIP_ERRNO;
+
+    if ((zi->ci.method == Z_DEFLATED) && (!zi->ci.raw))
+    {
+        err=deflateEnd(&zi->ci.stream);
+        zi->ci.stream_initialised = 0;
+    }
+
+    if (!zi->ci.raw)
+    {
+        crc32 = (uLong)zi->ci.crc32;
+        uncompressed_size = (uLong)zi->ci.stream.total_in;
+    }
+    compressed_size = (uLong)zi->ci.stream.total_out;
+#    ifndef NOCRYPT
+    compressed_size += zi->ci.crypt_header_size;
+#    endif
+
+    ziplocal_putValue_inmemory(zi->ci.central_header+16,crc32,4); /*crc*/
+    ziplocal_putValue_inmemory(zi->ci.central_header+20,
+                                compressed_size,4); /*compr size*/
+    if (zi->ci.stream.data_type == Z_ASCII)
+        ziplocal_putValue_inmemory(zi->ci.central_header+36,(uLong)Z_ASCII,2);
+    ziplocal_putValue_inmemory(zi->ci.central_header+24,
+                                uncompressed_size,4); /*uncompr size*/
+
+    if (err==ZIP_OK)
+        err = add_data_in_datablock(&zi->central_dir,zi->ci.central_header,
+                                       (uLong)zi->ci.size_centralheader);
+    free(zi->ci.central_header);
+
+    if (err==ZIP_OK)
+    {
+        long cur_pos_inzip = ZTELL(zi->z_filefunc,zi->filestream);
+        if (ZSEEK(zi->z_filefunc,zi->filestream,
+                  zi->ci.pos_local_header + 14,ZLIB_FILEFUNC_SEEK_SET)!=0)
+            err = ZIP_ERRNO;
+
+        if (err==ZIP_OK)
+            err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,crc32,4); /* crc 32, unknown */
+
+        if (err==ZIP_OK) /* compressed size, unknown */
+            err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,compressed_size,4);
+
+        if (err==ZIP_OK) /* uncompressed size, unknown */
+            err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,uncompressed_size,4);
+
+        if (ZSEEK(zi->z_filefunc,zi->filestream,
+                  cur_pos_inzip,ZLIB_FILEFUNC_SEEK_SET)!=0)
+            err = ZIP_ERRNO;
+    }
+
+    zi->number_entry ++;
+    zi->in_opened_file_inzip = 0;
+
+    return err;
+}
+
+extern int ZEXPORT zipCloseFileInZip (file)
+    zipFile file;
+{
+    return zipCloseFileInZipRaw (file,0,0);
+}
+
+extern int ZEXPORT zipClose (file, global_comment)
+    zipFile file;
+    const char* global_comment;
+{
+    zip_internal* zi;
+    int err = 0;
+    uLong size_centraldir = 0;
+    uLong centraldir_pos_inzip;
+    uInt size_global_comment;
+    if (file == NULL)
+        return ZIP_PARAMERROR;
+    zi = (zip_internal*)file;
+
+    if (zi->in_opened_file_inzip == 1)
+    {
+        err = zipCloseFileInZip (file);
+    }
+
+#ifndef NO_ADDFILEINEXISTINGZIP
+    if (global_comment==NULL)
+        global_comment = zi->globalcomment;
+#endif
+    if (global_comment==NULL)
+        size_global_comment = 0;
+    else
+        size_global_comment = (uInt)strlen(global_comment);
+
+    centraldir_pos_inzip = ZTELL(zi->z_filefunc,zi->filestream);
+    if (err==ZIP_OK)
+    {
+        linkedlist_datablock_internal* ldi = zi->central_dir.first_block ;
+        while (ldi!=NULL)
+        {
+            if ((err==ZIP_OK) && (ldi->filled_in_this_block>0))
+                if (ZWRITE(zi->z_filefunc,zi->filestream,
+                           ldi->data,ldi->filled_in_this_block)
+                              !=ldi->filled_in_this_block )
+                    err = ZIP_ERRNO;
+
+            size_centraldir += ldi->filled_in_this_block;
+            ldi = ldi->next_datablock;
+        }
+    }
+    free_datablock(zi->central_dir.first_block);
+
+    if (err==ZIP_OK) /* Magic End */
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)ENDHEADERMAGIC,4);
+
+    if (err==ZIP_OK) /* number of this disk */
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)0,2);
+
+    if (err==ZIP_OK) /* number of the disk with the start of the central directory */
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)0,2);
+
+    if (err==ZIP_OK) /* total number of entries in the central dir on this disk */
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)zi->number_entry,2);
+
+    if (err==ZIP_OK) /* total number of entries in the central dir */
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)zi->number_entry,2);
+
+    if (err==ZIP_OK) /* size of the central directory */
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)size_centraldir,4);
+
+    if (err==ZIP_OK) /* offset of start of central directory with respect to the
+                            starting disk number */
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,
+                                (uLong)(centraldir_pos_inzip - zi->add_position_when_writting_offset),4);
+
+    if (err==ZIP_OK) /* zipfile comment length */
+        err = ziplocal_putValue(&zi->z_filefunc,zi->filestream,(uLong)size_global_comment,2);
+
+    if ((err==ZIP_OK) && (size_global_comment>0))
+        if (ZWRITE(zi->z_filefunc,zi->filestream,
+                   global_comment,size_global_comment) != size_global_comment)
+                err = ZIP_ERRNO;
+
+    if (ZCLOSE(zi->z_filefunc,zi->filestream) != 0)
+        if (err == ZIP_OK)
+            err = ZIP_ERRNO;
+
+#ifndef NO_ADDFILEINEXISTINGZIP
+    TRYFREE(zi->globalcomment);
+#endif
+    TRYFREE(zi);
+
+    return err;
+}
diff --git a/gs/zlib/contrib/minizip/zip.h b/gs/zlib/contrib/minizip/zip.h
new file mode 100644
index 000000000..acacce83b
--- /dev/null
+++ b/gs/zlib/contrib/minizip/zip.h
@@ -0,0 +1,235 @@
+/* zip.h -- IO for compress .zip files using zlib
+   Version 1.01e, February 12th, 2005
+
+   Copyright (C) 1998-2005 Gilles Vollant
+
+   This unzip package allow creates .ZIP file, compatible with PKZip 2.04g
+     WinZip, InfoZip tools and compatible.
+   Multi volume ZipFile (span) are not supported.
+   Encryption compatible with pkzip 2.04g only supported
+   Old compressions used by old PKZip 1.x are not supported
+
+  For uncompress .zip file, look at unzip.h
+
+
+   I WAIT FEEDBACK at mail info@winimage.com
+   Visit also http://www.winimage.com/zLibDll/unzip.html for evolution
+
+   Condition of use and distribution are the same than zlib :
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+
+
+*/
+
+/* for more info about .ZIP format, see
+      http://www.info-zip.org/pub/infozip/doc/appnote-981119-iz.zip
+      http://www.info-zip.org/pub/infozip/doc/
+   PkWare has also a specification at :
+      ftp://ftp.pkware.com/probdesc.zip
+*/
+
+#ifndef _zip_H
+#define _zip_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef _ZLIB_H
+#include "zlib.h"
+#endif
+
+#ifndef _ZLIBIOAPI_H
+#include "ioapi.h"
+#endif
+
+#if defined(STRICTZIP) || defined(STRICTZIPUNZIP)
+/* like the STRICT of WIN32, we define a pointer that cannot be converted
+    from (void*) without cast */
+typedef struct TagzipFile__ { int unused; } zipFile__;
+typedef zipFile__ *zipFile;
+#else
+typedef voidp zipFile;
+#endif
+
+#define ZIP_OK                          (0)
+#define ZIP_EOF                         (0)
+#define ZIP_ERRNO                       (Z_ERRNO)
+#define ZIP_PARAMERROR                  (-102)
+#define ZIP_BADZIPFILE                  (-103)
+#define ZIP_INTERNALERROR               (-104)
+
+#ifndef DEF_MEM_LEVEL
+#  if MAX_MEM_LEVEL >= 8
+#    define DEF_MEM_LEVEL 8
+#  else
+#    define DEF_MEM_LEVEL  MAX_MEM_LEVEL
+#  endif
+#endif
+/* default memLevel */
+
+/* tm_zip contain date/time info */
+typedef struct tm_zip_s
+{
+    uInt tm_sec;            /* seconds after the minute - [0,59] */
+    uInt tm_min;            /* minutes after the hour - [0,59] */
+    uInt tm_hour;           /* hours since midnight - [0,23] */
+    uInt tm_mday;           /* day of the month - [1,31] */
+    uInt tm_mon;            /* months since January - [0,11] */
+    uInt tm_year;           /* years - [1980..2044] */
+} tm_zip;
+
+typedef struct
+{
+    tm_zip      tmz_date;       /* date in understandable format           */
+    uLong       dosDate;       /* if dos_date == 0, tmu_date is used      */
+/*    uLong       flag;        */   /* general purpose bit flag        2 bytes */
+
+    uLong       internal_fa;    /* internal file attributes        2 bytes */
+    uLong       external_fa;    /* external file attributes        4 bytes */
+} zip_fileinfo;
+
+typedef const char* zipcharpc;
+
+
+#define APPEND_STATUS_CREATE        (0)
+#define APPEND_STATUS_CREATEAFTER   (1)
+#define APPEND_STATUS_ADDINZIP      (2)
+
+extern zipFile ZEXPORT zipOpen OF((const char *pathname, int append));
+/*
+  Create a zipfile.
+     pathname contain on Windows XP a filename like "c:\\zlib\\zlib113.zip" or on
+       an Unix computer "zlib/zlib113.zip".
+     if the file pathname exist and append==APPEND_STATUS_CREATEAFTER, the zip
+       will be created at the end of the file.
+         (useful if the file contain a self extractor code)
+     if the file pathname exist and append==APPEND_STATUS_ADDINZIP, we will
+       add files in existing zip (be sure you don't add file that doesn't exist)
+     If the zipfile cannot be opened, the return value is NULL.
+     Else, the return value is a zipFile Handle, usable with other function
+       of this zip package.
+*/
+
+/* Note : there is no delete function into a zipfile.
+   If you want delete file into a zipfile, you must open a zipfile, and create another
+   Of couse, you can use RAW reading and writing to copy the file you did not want delte
+*/
+
+extern zipFile ZEXPORT zipOpen2 OF((const char *pathname,
+                                   int append,
+                                   zipcharpc* globalcomment,
+                                   zlib_filefunc_def* pzlib_filefunc_def));
+
+extern int ZEXPORT zipOpenNewFileInZip OF((zipFile file,
+                       const char* filename,
+                       const zip_fileinfo* zipfi,
+                       const void* extrafield_local,
+                       uInt size_extrafield_local,
+                       const void* extrafield_global,
+                       uInt size_extrafield_global,
+                       const char* comment,
+                       int method,
+                       int level));
+/*
+  Open a file in the ZIP for writing.
+  filename : the filename in zip (if NULL, '-' without quote will be used
+  *zipfi contain supplemental information
+  if extrafield_local!=NULL and size_extrafield_local>0, extrafield_local
+    contains the extrafield data the the local header
+  if extrafield_global!=NULL and size_extrafield_global>0, extrafield_global
+    contains the extrafield data the the local header
+  if comment != NULL, comment contain the comment string
+  method contain the compression method (0 for store, Z_DEFLATED for deflate)
+  level contain the level of compression (can be Z_DEFAULT_COMPRESSION)
+*/
+
+
+extern int ZEXPORT zipOpenNewFileInZip2 OF((zipFile file,
+                                            const char* filename,
+                                            const zip_fileinfo* zipfi,
+                                            const void* extrafield_local,
+                                            uInt size_extrafield_local,
+                                            const void* extrafield_global,
+                                            uInt size_extrafield_global,
+                                            const char* comment,
+                                            int method,
+                                            int level,
+                                            int raw));
+
+/*
+  Same than zipOpenNewFileInZip, except if raw=1, we write raw file
+ */
+
+extern int ZEXPORT zipOpenNewFileInZip3 OF((zipFile file,
+                                            const char* filename,
+                                            const zip_fileinfo* zipfi,
+                                            const void* extrafield_local,
+                                            uInt size_extrafield_local,
+                                            const void* extrafield_global,
+                                            uInt size_extrafield_global,
+                                            const char* comment,
+                                            int method,
+                                            int level,
+                                            int raw,
+                                            int windowBits,
+                                            int memLevel,
+                                            int strategy,
+                                            const char* password,
+                                            uLong crcForCtypting));
+
+/*
+  Same than zipOpenNewFileInZip2, except
+    windowBits,memLevel,,strategy : see parameter strategy in deflateInit2
+    password : crypting password (NULL for no crypting)
+    crcForCtypting : crc of file to compress (needed for crypting)
+ */
+
+
+extern int ZEXPORT zipWriteInFileInZip OF((zipFile file,
+                       const void* buf,
+                       unsigned len));
+/*
+  Write data in the zipfile
+*/
+
+extern int ZEXPORT zipCloseFileInZip OF((zipFile file));
+/*
+  Close the current file in the zipfile
+*/
+
+extern int ZEXPORT zipCloseFileInZipRaw OF((zipFile file,
+                                            uLong uncompressed_size,
+                                            uLong crc32));
+/*
+  Close the current file in the zipfile, for fiel opened with
+    parameter raw=1 in zipOpenNewFileInZip2
+  uncompressed_size and crc32 are value for the uncompressed size
+*/
+
+extern int ZEXPORT zipClose OF((zipFile file,
+                const char* global_comment));
+/*
+  Close the zipfile
+*/
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _zip_H */
diff --git a/gs/zlib/contrib/pascal/example.pas b/gs/zlib/contrib/pascal/example.pas
new file mode 100644
index 000000000..5518b36a7
--- /dev/null
+++ b/gs/zlib/contrib/pascal/example.pas
@@ -0,0 +1,599 @@
+(* example.c -- usage example of the zlib compression library
+ * Copyright (C) 1995-2003 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ *
+ * Pascal translation
+ * Copyright (C) 1998 by Jacques Nomssi Nzali.
+ * For conditions of distribution and use, see copyright notice in readme.txt
+ *
+ * Adaptation to the zlibpas interface
+ * Copyright (C) 2003 by Cosmin Truta.
+ * For conditions of distribution and use, see copyright notice in readme.txt
+ *)
+
+program example;
+
+{$DEFINE TEST_COMPRESS}
+{DO NOT $DEFINE TEST_GZIO}
+{$DEFINE TEST_DEFLATE}
+{$DEFINE TEST_INFLATE}
+{$DEFINE TEST_FLUSH}
+{$DEFINE TEST_SYNC}
+{$DEFINE TEST_DICT}
+
+uses SysUtils, zlibpas;
+
+const TESTFILE = 'foo.gz';
+
+(* "hello world" would be more standard, but the repeated "hello"
+ * stresses the compression code better, sorry...
+ *)
+const hello: PChar = 'hello, hello!';
+
+const dictionary: PChar = 'hello';
+
+var dictId: LongInt; (* Adler32 value of the dictionary *)
+
+procedure CHECK_ERR(err: Integer; msg: String);
+begin
+  if err <> Z_OK then
+  begin
+    WriteLn(msg, ' error: ', err);
+    Halt(1);
+  end;
+end;
+
+procedure EXIT_ERR(const msg: String);
+begin
+  WriteLn('Error: ', msg);
+  Halt(1);
+end;
+
+(* ===========================================================================
+ * Test compress and uncompress
+ *)
+{$IFDEF TEST_COMPRESS}
+procedure test_compress(compr: Pointer; comprLen: LongInt;
+                        uncompr: Pointer; uncomprLen: LongInt);
+var err: Integer;
+    len: LongInt;
+begin
+  len := StrLen(hello)+1;
+
+  err := compress(compr, comprLen, hello, len);
+  CHECK_ERR(err, 'compress');
+
+  StrCopy(PChar(uncompr), 'garbage');
+
+  err := uncompress(uncompr, uncomprLen, compr, comprLen);
+  CHECK_ERR(err, 'uncompress');
+
+  if StrComp(PChar(uncompr), hello) <> 0 then
+    EXIT_ERR('bad uncompress')
+  else
+    WriteLn('uncompress(): ', PChar(uncompr));
+end;
+{$ENDIF}
+
+(* ===========================================================================
+ * Test read/write of .gz files
+ *)
+{$IFDEF TEST_GZIO}
+procedure test_gzio(const fname: PChar; (* compressed file name *)
+                    uncompr: Pointer;
+                    uncomprLen: LongInt);
+var err: Integer;
+    len: Integer;
+    zfile: gzFile;
+    pos: LongInt;
+begin
+  len := StrLen(hello)+1;
+
+  zfile := gzopen(fname, 'wb');
+  if zfile = NIL then
+  begin
+    WriteLn('gzopen error');
+    Halt(1);
+  end;
+  gzputc(zfile, 'h');
+  if gzputs(zfile, 'ello') <> 4 then
+  begin
+    WriteLn('gzputs err: ', gzerror(zfile, err));
+    Halt(1);
+  end;
+  {$IFDEF GZ_FORMAT_STRING}
+  if gzprintf(zfile, ', %s!', 'hello') <> 8 then
+  begin
+    WriteLn('gzprintf err: ', gzerror(zfile, err));
+    Halt(1);
+  end;
+  {$ELSE}
+  if gzputs(zfile, ', hello!') <> 8 then
+  begin
+    WriteLn('gzputs err: ', gzerror(zfile, err));
+    Halt(1);
+  end;
+  {$ENDIF}
+  gzseek(zfile, 1, SEEK_CUR); (* add one zero byte *)
+  gzclose(zfile);
+
+  zfile := gzopen(fname, 'rb');
+  if zfile = NIL then
+  begin
+    WriteLn('gzopen error');
+    Halt(1);
+  end;
+
+  StrCopy(PChar(uncompr), 'garbage');
+
+  if gzread(zfile, uncompr, uncomprLen) <> len then
+  begin
+    WriteLn('gzread err: ', gzerror(zfile, err));
+    Halt(1);
+  end;
+  if StrComp(PChar(uncompr), hello) <> 0 then
+  begin
+    WriteLn('bad gzread: ', PChar(uncompr));
+    Halt(1);
+  end
+  else
+    WriteLn('gzread(): ', PChar(uncompr));
+
+  pos := gzseek(zfile, -8, SEEK_CUR);
+  if (pos <> 6) or (gztell(zfile) <> pos) then
+  begin
+    WriteLn('gzseek error, pos=', pos, ', gztell=', gztell(zfile));
+    Halt(1);
+  end;
+
+  if gzgetc(zfile) <> ' ' then
+  begin
+    WriteLn('gzgetc error');
+    Halt(1);
+  end;
+
+  if gzungetc(' ', zfile) <> ' ' then
+  begin
+    WriteLn('gzungetc error');
+    Halt(1);
+  end;
+
+  gzgets(zfile, PChar(uncompr), uncomprLen);
+  uncomprLen := StrLen(PChar(uncompr));
+  if uncomprLen <> 7 then (* " hello!" *)
+  begin
+    WriteLn('gzgets err after gzseek: ', gzerror(zfile, err));
+    Halt(1);
+  end;
+  if StrComp(PChar(uncompr), hello + 6) <> 0 then
+  begin
+    WriteLn('bad gzgets after gzseek');
+    Halt(1);
+  end
+  else
+    WriteLn('gzgets() after gzseek: ', PChar(uncompr));
+
+  gzclose(zfile);
+end;
+{$ENDIF}
+
+(* ===========================================================================
+ * Test deflate with small buffers
+ *)
+{$IFDEF TEST_DEFLATE}
+procedure test_deflate(compr: Pointer; comprLen: LongInt);
+var c_stream: z_stream; (* compression stream *)
+    err: Integer;
+    len: LongInt;
+begin
+  len := StrLen(hello)+1;
+
+  c_stream.zalloc := NIL;
+  c_stream.zfree := NIL;
+  c_stream.opaque := NIL;
+
+  err := deflateInit(c_stream, Z_DEFAULT_COMPRESSION);
+  CHECK_ERR(err, 'deflateInit');
+
+  c_stream.next_in := hello;
+  c_stream.next_out := compr;
+
+  while (c_stream.total_in <> len) and
+        (c_stream.total_out < comprLen) do
+  begin
+    c_stream.avail_out := 1; { force small buffers }
+    c_stream.avail_in := 1;
+    err := deflate(c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, 'deflate');
+  end;
+
+  (* Finish the stream, still forcing small buffers: *)
+  while TRUE do
+  begin
+    c_stream.avail_out := 1;
+    err := deflate(c_stream, Z_FINISH);
+    if err = Z_STREAM_END then
+      break;
+    CHECK_ERR(err, 'deflate');
+  end;
+
+  err := deflateEnd(c_stream);
+  CHECK_ERR(err, 'deflateEnd');
+end;
+{$ENDIF}
+
+(* ===========================================================================
+ * Test inflate with small buffers
+ *)
+{$IFDEF TEST_INFLATE}
+procedure test_inflate(compr: Pointer; comprLen : LongInt;
+                       uncompr: Pointer; uncomprLen : LongInt);
+var err: Integer;
+    d_stream: z_stream; (* decompression stream *)
+begin
+  StrCopy(PChar(uncompr), 'garbage');
+
+  d_stream.zalloc := NIL;
+  d_stream.zfree := NIL;
+  d_stream.opaque := NIL;
+
+  d_stream.next_in := compr;
+  d_stream.avail_in := 0;
+  d_stream.next_out := uncompr;
+
+  err := inflateInit(d_stream);
+  CHECK_ERR(err, 'inflateInit');
+
+  while (d_stream.total_out < uncomprLen) and
+        (d_stream.total_in < comprLen) do
+  begin
+    d_stream.avail_out := 1; (* force small buffers *)
+    d_stream.avail_in := 1;
+    err := inflate(d_stream, Z_NO_FLUSH);
+    if err = Z_STREAM_END then
+      break;
+    CHECK_ERR(err, 'inflate');
+  end;
+
+  err := inflateEnd(d_stream);
+  CHECK_ERR(err, 'inflateEnd');
+
+  if StrComp(PChar(uncompr), hello) <> 0 then
+    EXIT_ERR('bad inflate')
+  else
+    WriteLn('inflate(): ', PChar(uncompr));
+end;
+{$ENDIF}
+
+(* ===========================================================================
+ * Test deflate with large buffers and dynamic change of compression level
+ *)
+{$IFDEF TEST_DEFLATE}
+procedure test_large_deflate(compr: Pointer; comprLen: LongInt;
+                             uncompr: Pointer; uncomprLen: LongInt);
+var c_stream: z_stream; (* compression stream *)
+    err: Integer;
+begin
+  c_stream.zalloc := NIL;
+  c_stream.zfree := NIL;
+  c_stream.opaque := NIL;
+
+  err := deflateInit(c_stream, Z_BEST_SPEED);
+  CHECK_ERR(err, 'deflateInit');
+
+  c_stream.next_out := compr;
+  c_stream.avail_out := Integer(comprLen);
+
+  (* At this point, uncompr is still mostly zeroes, so it should compress
+   * very well:
+   *)
+  c_stream.next_in := uncompr;
+  c_stream.avail_in := Integer(uncomprLen);
+  err := deflate(c_stream, Z_NO_FLUSH);
+  CHECK_ERR(err, 'deflate');
+  if c_stream.avail_in <> 0 then
+    EXIT_ERR('deflate not greedy');
+
+  (* Feed in already compressed data and switch to no compression: *)
+  deflateParams(c_stream, Z_NO_COMPRESSION, Z_DEFAULT_STRATEGY);
+  c_stream.next_in := compr;
+  c_stream.avail_in := Integer(comprLen div 2);
+  err := deflate(c_stream, Z_NO_FLUSH);
+  CHECK_ERR(err, 'deflate');
+
+  (* Switch back to compressing mode: *)
+  deflateParams(c_stream, Z_BEST_COMPRESSION, Z_FILTERED);
+  c_stream.next_in := uncompr;
+  c_stream.avail_in := Integer(uncomprLen);
+  err := deflate(c_stream, Z_NO_FLUSH);
+  CHECK_ERR(err, 'deflate');
+
+  err := deflate(c_stream, Z_FINISH);
+  if err <> Z_STREAM_END then
+    EXIT_ERR('deflate should report Z_STREAM_END');
+
+  err := deflateEnd(c_stream);
+  CHECK_ERR(err, 'deflateEnd');
+end;
+{$ENDIF}
+
+(* ===========================================================================
+ * Test inflate with large buffers
+ *)
+{$IFDEF TEST_INFLATE}
+procedure test_large_inflate(compr: Pointer; comprLen: LongInt;
+                             uncompr: Pointer; uncomprLen: LongInt);
+var err: Integer;
+    d_stream: z_stream; (* decompression stream *)
+begin
+  StrCopy(PChar(uncompr), 'garbage');
+
+  d_stream.zalloc := NIL;
+  d_stream.zfree := NIL;
+  d_stream.opaque := NIL;
+
+  d_stream.next_in := compr;
+  d_stream.avail_in := Integer(comprLen);
+
+  err := inflateInit(d_stream);
+  CHECK_ERR(err, 'inflateInit');
+
+  while TRUE do
+  begin
+    d_stream.next_out := uncompr;            (* discard the output *)
+    d_stream.avail_out := Integer(uncomprLen);
+    err := inflate(d_stream, Z_NO_FLUSH);
+    if err = Z_STREAM_END then
+      break;
+    CHECK_ERR(err, 'large inflate');
+  end;
+
+  err := inflateEnd(d_stream);
+  CHECK_ERR(err, 'inflateEnd');
+
+  if d_stream.total_out <> 2 * uncomprLen + comprLen div 2 then
+  begin
+    WriteLn('bad large inflate: ', d_stream.total_out);
+    Halt(1);
+  end
+  else
+    WriteLn('large_inflate(): OK');
+end;
+{$ENDIF}
+
+(* ===========================================================================
+ * Test deflate with full flush
+ *)
+{$IFDEF TEST_FLUSH}
+procedure test_flush(compr: Pointer; var comprLen : LongInt);
+var c_stream: z_stream; (* compression stream *)
+    err: Integer;
+    len: Integer;
+begin
+  len := StrLen(hello)+1;
+
+  c_stream.zalloc := NIL;
+  c_stream.zfree := NIL;
+  c_stream.opaque := NIL;
+
+  err := deflateInit(c_stream, Z_DEFAULT_COMPRESSION);
+  CHECK_ERR(err, 'deflateInit');
+
+  c_stream.next_in := hello;
+  c_stream.next_out := compr;
+  c_stream.avail_in := 3;
+  c_stream.avail_out := Integer(comprLen);
+  err := deflate(c_stream, Z_FULL_FLUSH);
+  CHECK_ERR(err, 'deflate');
+
+  Inc(PByteArray(compr)^[3]); (* force an error in first compressed block *)
+  c_stream.avail_in := len - 3;
+
+  err := deflate(c_stream, Z_FINISH);
+  if err <> Z_STREAM_END then
+    CHECK_ERR(err, 'deflate');
+
+  err := deflateEnd(c_stream);
+  CHECK_ERR(err, 'deflateEnd');
+
+  comprLen := c_stream.total_out;
+end;
+{$ENDIF}
+
+(* ===========================================================================
+ * Test inflateSync()
+ *)
+{$IFDEF TEST_SYNC}
+procedure test_sync(compr: Pointer; comprLen: LongInt;
+                    uncompr: Pointer; uncomprLen : LongInt);
+var err: Integer;
+    d_stream: z_stream; (* decompression stream *)
+begin
+  StrCopy(PChar(uncompr), 'garbage');
+
+  d_stream.zalloc := NIL;
+  d_stream.zfree := NIL;
+  d_stream.opaque := NIL;
+
+  d_stream.next_in := compr;
+  d_stream.avail_in := 2; (* just read the zlib header *)
+
+  err := inflateInit(d_stream);
+  CHECK_ERR(err, 'inflateInit');
+
+  d_stream.next_out := uncompr;
+  d_stream.avail_out := Integer(uncomprLen);
+
+  inflate(d_stream, Z_NO_FLUSH);
+  CHECK_ERR(err, 'inflate');
+
+  d_stream.avail_in := Integer(comprLen-2);   (* read all compressed data *)
+  err := inflateSync(d_stream);               (* but skip the damaged part *)
+  CHECK_ERR(err, 'inflateSync');
+
+  err := inflate(d_stream, Z_FINISH);
+  if err <> Z_DATA_ERROR then
+    EXIT_ERR('inflate should report DATA_ERROR');
+    (* Because of incorrect adler32 *)
+
+  err := inflateEnd(d_stream);
+  CHECK_ERR(err, 'inflateEnd');
+
+  WriteLn('after inflateSync(): hel', PChar(uncompr));
+end;
+{$ENDIF}
+
+(* ===========================================================================
+ * Test deflate with preset dictionary
+ *)
+{$IFDEF TEST_DICT}
+procedure test_dict_deflate(compr: Pointer; comprLen: LongInt);
+var c_stream: z_stream; (* compression stream *)
+    err: Integer;
+begin
+  c_stream.zalloc := NIL;
+  c_stream.zfree := NIL;
+  c_stream.opaque := NIL;
+
+  err := deflateInit(c_stream, Z_BEST_COMPRESSION);
+  CHECK_ERR(err, 'deflateInit');
+
+  err := deflateSetDictionary(c_stream, dictionary, StrLen(dictionary));
+  CHECK_ERR(err, 'deflateSetDictionary');
+
+  dictId := c_stream.adler;
+  c_stream.next_out := compr;
+  c_stream.avail_out := Integer(comprLen);
+
+  c_stream.next_in := hello;
+  c_stream.avail_in := StrLen(hello)+1;
+
+  err := deflate(c_stream, Z_FINISH);
+  if err <> Z_STREAM_END then
+    EXIT_ERR('deflate should report Z_STREAM_END');
+
+  err := deflateEnd(c_stream);
+  CHECK_ERR(err, 'deflateEnd');
+end;
+{$ENDIF}
+
+(* ===========================================================================
+ * Test inflate with a preset dictionary
+ *)
+{$IFDEF TEST_DICT}
+procedure test_dict_inflate(compr: Pointer; comprLen: LongInt;
+                            uncompr: Pointer; uncomprLen: LongInt);
+var err: Integer;
+    d_stream: z_stream; (* decompression stream *)
+begin
+  StrCopy(PChar(uncompr), 'garbage');
+
+  d_stream.zalloc := NIL;
+  d_stream.zfree := NIL;
+  d_stream.opaque := NIL;
+
+  d_stream.next_in := compr;
+  d_stream.avail_in := Integer(comprLen);
+
+  err := inflateInit(d_stream);
+  CHECK_ERR(err, 'inflateInit');
+
+  d_stream.next_out := uncompr;
+  d_stream.avail_out := Integer(uncomprLen);
+
+  while TRUE do
+  begin
+    err := inflate(d_stream, Z_NO_FLUSH);
+    if err = Z_STREAM_END then
+      break;
+    if err = Z_NEED_DICT then
+    begin
+      if d_stream.adler <> dictId then
+        EXIT_ERR('unexpected dictionary');
+      err := inflateSetDictionary(d_stream, dictionary, StrLen(dictionary));
+    end;
+    CHECK_ERR(err, 'inflate with dict');
+  end;
+
+  err := inflateEnd(d_stream);
+  CHECK_ERR(err, 'inflateEnd');
+
+  if StrComp(PChar(uncompr), hello) <> 0 then
+    EXIT_ERR('bad inflate with dict')
+  else
+    WriteLn('inflate with dictionary: ', PChar(uncompr));
+end;
+{$ENDIF}
+
+var compr, uncompr: Pointer;
+    comprLen, uncomprLen: LongInt;
+
+begin
+  if zlibVersion^ <> ZLIB_VERSION[1] then
+    EXIT_ERR('Incompatible zlib version');
+
+  WriteLn('zlib version: ', zlibVersion);
+  WriteLn('zlib compile flags: ', Format('0x%x', [zlibCompileFlags]));
+
+  comprLen := 10000 * SizeOf(Integer); (* don't overflow on MSDOS *)
+  uncomprLen := comprLen;
+  GetMem(compr, comprLen);
+  GetMem(uncompr, uncomprLen);
+  if (compr = NIL) or (uncompr = NIL) then
+    EXIT_ERR('Out of memory');
+  (* compr and uncompr are cleared to avoid reading uninitialized
+   * data and to ensure that uncompr compresses well.
+   *)
+  FillChar(compr^, comprLen, 0);
+  FillChar(uncompr^, uncomprLen, 0);
+
+  {$IFDEF TEST_COMPRESS}
+  WriteLn('** Testing compress');
+  test_compress(compr, comprLen, uncompr, uncomprLen);
+  {$ENDIF}
+
+  {$IFDEF TEST_GZIO}
+  WriteLn('** Testing gzio');
+  if ParamCount >= 1 then
+    test_gzio(ParamStr(1), uncompr, uncomprLen)
+  else
+    test_gzio(TESTFILE, uncompr, uncomprLen);
+  {$ENDIF}
+
+  {$IFDEF TEST_DEFLATE}
+  WriteLn('** Testing deflate with small buffers');
+  test_deflate(compr, comprLen);
+  {$ENDIF}
+  {$IFDEF TEST_INFLATE}
+  WriteLn('** Testing inflate with small buffers');
+  test_inflate(compr, comprLen, uncompr, uncomprLen);
+  {$ENDIF}
+
+  {$IFDEF TEST_DEFLATE}
+  WriteLn('** Testing deflate with large buffers');
+  test_large_deflate(compr, comprLen, uncompr, uncomprLen);
+  {$ENDIF}
+  {$IFDEF TEST_INFLATE}
+  WriteLn('** Testing inflate with large buffers');
+  test_large_inflate(compr, comprLen, uncompr, uncomprLen);
+  {$ENDIF}
+
+  {$IFDEF TEST_FLUSH}
+  WriteLn('** Testing deflate with full flush');
+  test_flush(compr, comprLen);
+  {$ENDIF}
+  {$IFDEF TEST_SYNC}
+  WriteLn('** Testing inflateSync');
+  test_sync(compr, comprLen, uncompr, uncomprLen);
+  {$ENDIF}
+  comprLen := uncomprLen;
+
+  {$IFDEF TEST_DICT}
+  WriteLn('** Testing deflate and inflate with preset dictionary');
+  test_dict_deflate(compr, comprLen);
+  test_dict_inflate(compr, comprLen, uncompr, uncomprLen);
+  {$ENDIF}
+
+  FreeMem(compr, comprLen);
+  FreeMem(uncompr, uncomprLen);
+end.
diff --git a/gs/zlib/contrib/pascal/readme.txt b/gs/zlib/contrib/pascal/readme.txt
new file mode 100644
index 000000000..60e87c8a3
--- /dev/null
+++ b/gs/zlib/contrib/pascal/readme.txt
@@ -0,0 +1,76 @@
+
+This directory contains a Pascal (Delphi, Kylix) interface to the
+zlib data compression library.
+
+
+Directory listing
+=================
+
+zlibd32.mak     makefile for Borland C++
+example.pas     usage example of zlib
+zlibpas.pas     the Pascal interface to zlib
+readme.txt      this file
+
+
+Compatibility notes
+===================
+
+- Although the name "zlib" would have been more normal for the
+  zlibpas unit, this name is already taken by Borland's ZLib unit.
+  This is somehow unfortunate, because that unit is not a genuine
+  interface to the full-fledged zlib functionality, but a suite of
+  class wrappers around zlib streams.  Other essential features,
+  such as checksums, are missing.
+  It would have been more appropriate for that unit to have a name
+  like "ZStreams", or something similar.
+
+- The C and zlib-supplied types int, uInt, long, uLong, etc. are
+  translated directly into Pascal types of similar sizes (Integer,
+  LongInt, etc.), to avoid namespace pollution.  In particular,
+  there is no conversion of unsigned int into a Pascal unsigned
+  integer.  The Word type is non-portable and has the same size
+  (16 bits) both in a 16-bit and in a 32-bit environment, unlike
+  Integer.  Even if there is a 32-bit Cardinal type, there is no
+  real need for unsigned int in zlib under a 32-bit environment.
+
+- Except for the callbacks, the zlib function interfaces are
+  assuming the calling convention normally used in Pascal
+  (__pascal for DOS and Windows16, __fastcall for Windows32).
+  Since the cdecl keyword is used, the old Turbo Pascal does
+  not work with this interface.
+
+- The gz* function interfaces are not translated, to avoid
+  interfacing problems with the C runtime library.  Besides,
+    gzprintf(gzFile file, const char *format, ...)
+  cannot be translated into Pascal.
+
+
+Legal issues
+============
+
+The zlibpas interface is:
+  Copyright (C) 1995-2003 Jean-loup Gailly and Mark Adler.
+  Copyright (C) 1998 by Bob Dellaca.
+  Copyright (C) 2003 by Cosmin Truta.
+
+The example program is:
+  Copyright (C) 1995-2003 by Jean-loup Gailly.
+  Copyright (C) 1998,1999,2000 by Jacques Nomssi Nzali.
+  Copyright (C) 2003 by Cosmin Truta.
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the author be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+
diff --git a/gs/zlib/contrib/pascal/zlibd32.mak b/gs/zlib/contrib/pascal/zlibd32.mak
new file mode 100644
index 000000000..88fafa0b1
--- /dev/null
+++ b/gs/zlib/contrib/pascal/zlibd32.mak
@@ -0,0 +1,93 @@
+# Makefile for zlib
+# For use with Delphi and C++ Builder under Win32
+# Updated for zlib 1.2.x by Cosmin Truta
+
+# ------------ Borland C++ ------------
+
+# This project uses the Delphi (fastcall/register) calling convention:
+LOC = -DZEXPORT=__fastcall -DZEXPORTVA=__cdecl
+
+CC = bcc32
+LD = bcc32
+AR = tlib
+# do not use "-pr" in CFLAGS
+CFLAGS = -a -d -k- -O2 $(LOC)
+LDFLAGS =
+
+
+# variables
+ZLIB_LIB = zlib.lib
+
+OBJ1 = adler32.obj compress.obj crc32.obj deflate.obj gzio.obj infback.obj
+OBJ2 = inffast.obj inflate.obj inftrees.obj trees.obj uncompr.obj zutil.obj
+OBJP1 = +adler32.obj+compress.obj+crc32.obj+deflate.obj+gzio.obj+infback.obj
+OBJP2 = +inffast.obj+inflate.obj+inftrees.obj+trees.obj+uncompr.obj+zutil.obj
+
+
+# targets
+all: $(ZLIB_LIB) example.exe minigzip.exe
+
+.c.obj:
+	$(CC) -c $(CFLAGS) $*.c
+
+adler32.obj: adler32.c zlib.h zconf.h
+
+compress.obj: compress.c zlib.h zconf.h
+
+crc32.obj: crc32.c zlib.h zconf.h crc32.h
+
+deflate.obj: deflate.c deflate.h zutil.h zlib.h zconf.h
+
+gzio.obj: gzio.c zutil.h zlib.h zconf.h
+
+infback.obj: infback.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inffast.obj: inffast.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h
+
+inflate.obj: inflate.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inftrees.obj: inftrees.c zutil.h zlib.h zconf.h inftrees.h
+
+trees.obj: trees.c zutil.h zlib.h zconf.h deflate.h trees.h
+
+uncompr.obj: uncompr.c zlib.h zconf.h
+
+zutil.obj: zutil.c zutil.h zlib.h zconf.h
+
+example.obj: example.c zlib.h zconf.h
+
+minigzip.obj: minigzip.c zlib.h zconf.h
+
+
+# For the sake of the old Borland make,
+# the command line is cut to fit in the MS-DOS 128 byte limit:
+$(ZLIB_LIB): $(OBJ1) $(OBJ2)
+	-del $(ZLIB_LIB)
+	$(AR) $(ZLIB_LIB) $(OBJP1)
+	$(AR) $(ZLIB_LIB) $(OBJP2)
+
+
+# testing
+test: example.exe minigzip.exe
+	example
+	echo hello world | minigzip | minigzip -d
+
+example.exe: example.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) example.obj $(ZLIB_LIB)
+
+minigzip.exe: minigzip.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) minigzip.obj $(ZLIB_LIB)
+
+
+# cleanup
+clean:
+	-del *.obj
+	-del *.exe
+	-del *.lib
+	-del *.tds
+	-del zlib.bak
+	-del foo.gz
+
diff --git a/gs/zlib/contrib/pascal/zlibpas.pas b/gs/zlib/contrib/pascal/zlibpas.pas
new file mode 100644
index 000000000..836848c2b
--- /dev/null
+++ b/gs/zlib/contrib/pascal/zlibpas.pas
@@ -0,0 +1,236 @@
+(* zlibpas -- Pascal interface to the zlib data compression library
+ *
+ * Copyright (C) 2003 Cosmin Truta.
+ * Derived from original sources by Bob Dellaca.
+ * For conditions of distribution and use, see copyright notice in readme.txt
+ *)
+
+unit zlibpas;
+
+interface
+
+const
+  ZLIB_VERSION = '1.2.3';
+
+type
+  alloc_func = function(opaque: Pointer; items, size: Integer): Pointer;
+                 cdecl;
+  free_func  = procedure(opaque, address: Pointer);
+                 cdecl;
+
+  in_func    = function(opaque: Pointer; var buf: PByte): Integer;
+                 cdecl;
+  out_func   = function(opaque: Pointer; buf: PByte; size: Integer): Integer;
+                 cdecl;
+
+  z_streamp = ^z_stream;
+  z_stream = packed record
+    next_in: PChar;       (* next input byte *)
+    avail_in: Integer;    (* number of bytes available at next_in *)
+    total_in: LongInt;    (* total nb of input bytes read so far *)
+
+    next_out: PChar;      (* next output byte should be put there *)
+    avail_out: Integer;   (* remaining free space at next_out *)
+    total_out: LongInt;   (* total nb of bytes output so far *)
+
+    msg: PChar;           (* last error message, NULL if no error *)
+    state: Pointer;       (* not visible by applications *)
+
+    zalloc: alloc_func;   (* used to allocate the internal state *)
+    zfree: free_func;     (* used to free the internal state *)
+    opaque: Pointer;      (* private data object passed to zalloc and zfree *)
+
+    data_type: Integer;   (* best guess about the data type: ascii or binary *)
+    adler: LongInt;       (* adler32 value of the uncompressed data *)
+    reserved: LongInt;    (* reserved for future use *)
+  end;
+
+(* constants *)
+const
+  Z_NO_FLUSH      = 0;
+  Z_PARTIAL_FLUSH = 1;
+  Z_SYNC_FLUSH    = 2;
+  Z_FULL_FLUSH    = 3;
+  Z_FINISH        = 4;
+
+  Z_OK            =  0;
+  Z_STREAM_END    =  1;
+  Z_NEED_DICT     =  2;
+  Z_ERRNO         = -1;
+  Z_STREAM_ERROR  = -2;
+  Z_DATA_ERROR    = -3;
+  Z_MEM_ERROR     = -4;
+  Z_BUF_ERROR     = -5;
+  Z_VERSION_ERROR = -6;
+
+  Z_NO_COMPRESSION       =  0;
+  Z_BEST_SPEED           =  1;
+  Z_BEST_COMPRESSION     =  9;
+  Z_DEFAULT_COMPRESSION  = -1;
+
+  Z_FILTERED            = 1;
+  Z_HUFFMAN_ONLY        = 2;
+  Z_RLE                 = 3;
+  Z_DEFAULT_STRATEGY    = 0;
+
+  Z_BINARY   = 0;
+  Z_ASCII    = 1;
+  Z_UNKNOWN  = 2;
+
+  Z_DEFLATED = 8;
+
+(* basic functions *)
+function zlibVersion: PChar;
+function deflateInit(var strm: z_stream; level: Integer): Integer;
+function deflate(var strm: z_stream; flush: Integer): Integer;
+function deflateEnd(var strm: z_stream): Integer;
+function inflateInit(var strm: z_stream): Integer;
+function inflate(var strm: z_stream; flush: Integer): Integer;
+function inflateEnd(var strm: z_stream): Integer;
+
+(* advanced functions *)
+function deflateInit2(var strm: z_stream; level, method, windowBits,
+                      memLevel, strategy: Integer): Integer;
+function deflateSetDictionary(var strm: z_stream; const dictionary: PChar;
+                              dictLength: Integer): Integer;
+function deflateCopy(var dest, source: z_stream): Integer;
+function deflateReset(var strm: z_stream): Integer;
+function deflateParams(var strm: z_stream; level, strategy: Integer): Integer;
+function deflateBound(var strm: z_stream; sourceLen: LongInt): LongInt;
+function deflatePrime(var strm: z_stream; bits, value: Integer): Integer;
+function inflateInit2(var strm: z_stream; windowBits: Integer): Integer;
+function inflateSetDictionary(var strm: z_stream; const dictionary: PChar;
+                              dictLength: Integer): Integer;
+function inflateSync(var strm: z_stream): Integer;
+function inflateCopy(var dest, source: z_stream): Integer;
+function inflateReset(var strm: z_stream): Integer;
+function inflateBackInit(var strm: z_stream;
+                         windowBits: Integer; window: PChar): Integer;
+function inflateBack(var strm: z_stream; in_fn: in_func; in_desc: Pointer;
+                     out_fn: out_func; out_desc: Pointer): Integer;
+function inflateBackEnd(var strm: z_stream): Integer;
+function zlibCompileFlags: LongInt;
+
+(* utility functions *)
+function compress(dest: PChar; var destLen: LongInt;
+                  const source: PChar; sourceLen: LongInt): Integer;
+function compress2(dest: PChar; var destLen: LongInt;
+                  const source: PChar; sourceLen: LongInt;
+                  level: Integer): Integer;
+function compressBound(sourceLen: LongInt): LongInt;
+function uncompress(dest: PChar; var destLen: LongInt;
+                    const source: PChar; sourceLen: LongInt): Integer;
+
+(* checksum functions *)
+function adler32(adler: LongInt; const buf: PChar; len: Integer): LongInt;
+function crc32(crc: LongInt; const buf: PChar; len: Integer): LongInt;
+
+(* various hacks, don't look :) *)
+function deflateInit_(var strm: z_stream; level: Integer;
+                      const version: PChar; stream_size: Integer): Integer;
+function inflateInit_(var strm: z_stream; const version: PChar;
+                      stream_size: Integer): Integer;
+function deflateInit2_(var strm: z_stream;
+                       level, method, windowBits, memLevel, strategy: Integer;
+                       const version: PChar; stream_size: Integer): Integer;
+function inflateInit2_(var strm: z_stream; windowBits: Integer;
+                       const version: PChar; stream_size: Integer): Integer;
+function inflateBackInit_(var strm: z_stream;
+                          windowBits: Integer; window: PChar;
+                          const version: PChar; stream_size: Integer): Integer;
+
+
+implementation
+
+{$L adler32.obj}
+{$L compress.obj}
+{$L crc32.obj}
+{$L deflate.obj}
+{$L infback.obj}
+{$L inffast.obj}
+{$L inflate.obj}
+{$L inftrees.obj}
+{$L trees.obj}
+{$L uncompr.obj}
+{$L zutil.obj}
+
+function adler32; external;
+function compress; external;
+function compress2; external;
+function compressBound; external;
+function crc32; external;
+function deflate; external;
+function deflateBound; external;
+function deflateCopy; external;
+function deflateEnd; external;
+function deflateInit_; external;
+function deflateInit2_; external;
+function deflateParams; external;
+function deflatePrime; external;
+function deflateReset; external;
+function deflateSetDictionary; external;
+function inflate; external;
+function inflateBack; external;
+function inflateBackEnd; external;
+function inflateBackInit_; external;
+function inflateCopy; external;
+function inflateEnd; external;
+function inflateInit_; external;
+function inflateInit2_; external;
+function inflateReset; external;
+function inflateSetDictionary; external;
+function inflateSync; external;
+function uncompress; external;
+function zlibCompileFlags; external;
+function zlibVersion; external;
+
+function deflateInit(var strm: z_stream; level: Integer): Integer;
+begin
+  Result := deflateInit_(strm, level, ZLIB_VERSION, sizeof(z_stream));
+end;
+
+function deflateInit2(var strm: z_stream; level, method, windowBits, memLevel,
+                      strategy: Integer): Integer;
+begin
+  Result := deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
+                          ZLIB_VERSION, sizeof(z_stream));
+end;
+
+function inflateInit(var strm: z_stream): Integer;
+begin
+  Result := inflateInit_(strm, ZLIB_VERSION, sizeof(z_stream));
+end;
+
+function inflateInit2(var strm: z_stream; windowBits: Integer): Integer;
+begin
+  Result := inflateInit2_(strm, windowBits, ZLIB_VERSION, sizeof(z_stream));
+end;
+
+function inflateBackInit(var strm: z_stream;
+                         windowBits: Integer; window: PChar): Integer;
+begin
+  Result := inflateBackInit_(strm, windowBits, window,
+                             ZLIB_VERSION, sizeof(z_stream));
+end;
+
+function _malloc(Size: Integer): Pointer; cdecl;
+begin
+  GetMem(Result, Size);
+end;
+
+procedure _free(Block: Pointer); cdecl;
+begin
+  FreeMem(Block);
+end;
+
+procedure _memset(P: Pointer; B: Byte; count: Integer); cdecl;
+begin
+  FillChar(P^, count, B);
+end;
+
+procedure _memcpy(dest, source: Pointer; count: Integer); cdecl;
+begin
+  Move(source^, dest^, count);
+end;
+
+end.
diff --git a/gs/zlib/contrib/puff/Makefile b/gs/zlib/contrib/puff/Makefile
new file mode 100644
index 000000000..b6b69404c
--- /dev/null
+++ b/gs/zlib/contrib/puff/Makefile
@@ -0,0 +1,8 @@
+puff: puff.c puff.h
+	cc -DTEST -o puff puff.c
+
+test: puff
+	puff zeros.raw
+
+clean:
+	rm -f puff puff.o
diff --git a/gs/zlib/contrib/puff/README b/gs/zlib/contrib/puff/README
new file mode 100644
index 000000000..bbc4cb595
--- /dev/null
+++ b/gs/zlib/contrib/puff/README
@@ -0,0 +1,63 @@
+Puff -- A Simple Inflate
+3 Mar 2003
+Mark Adler
+madler@alumni.caltech.edu
+
+What this is --
+
+puff.c provides the routine puff() to decompress the deflate data format.  It
+does so more slowly than zlib, but the code is about one-fifth the size of the
+inflate code in zlib, and written to be very easy to read.
+
+Why I wrote this --
+
+puff.c was written to document the deflate format unambiguously, by virtue of
+being working C code.  It is meant to supplement RFC 1951, which formally
+describes the deflate format.  I have received many questions on details of the
+deflate format, and I hope that reading this code will answer those questions.
+puff.c is heavily commented with details of the deflate format, especially
+those little nooks and cranies of the format that might not be obvious from a
+specification.
+
+puff.c may also be useful in applications where code size or memory usage is a
+very limited resource, and speed is not as important.
+
+How to use it --
+
+Well, most likely you should just be reading puff.c and using zlib for actual
+applications, but if you must ...
+
+Include puff.h in your code, which provides this prototype:
+
+int puff(unsigned char *dest,           /* pointer to destination pointer */
+         unsigned long *destlen,        /* amount of output space */
+         unsigned char *source,         /* pointer to source data pointer */
+         unsigned long *sourcelen);     /* amount of input available */
+
+Then you can call puff() to decompress a deflate stream that is in memory in
+its entirety at source, to a sufficiently sized block of memory for the
+decompressed data at dest.  puff() is the only external symbol in puff.c  The
+only C library functions that puff.c needs are setjmp() and longjmp(), which
+are used to simplify error checking in the code to improve readabilty.  puff.c
+does no memory allocation, and uses less than 2K bytes off of the stack.
+
+If destlen is not enough space for the uncompressed data, then inflate will
+return an error without writing more than destlen bytes.  Note that this means
+that in order to decompress the deflate data successfully, you need to know
+the size of the uncompressed data ahead of time.
+
+If needed, puff() can determine the size of the uncompressed data with no
+output space.  This is done by passing dest equal to (unsigned char *)0.  Then
+the initial value of *destlen is ignored and *destlen is set to the length of
+the uncompressed data.  So if the size of the uncompressed data is not known,
+then two passes of puff() can be used--first to determine the size, and second
+to do the actual inflation after allocating the appropriate memory.  Not
+pretty, but it works.  (This is one of the reasons you should be using zlib.)
+
+The deflate format is self-terminating.  If the deflate stream does not end
+in *sourcelen bytes, puff() will return an error without reading at or past
+endsource.
+
+On return, *sourcelen is updated to the amount of input data consumed, and
+*destlen is updated to the size of the uncompressed data.  See the comments
+in puff.c for the possible return codes for puff().
diff --git a/gs/zlib/contrib/puff/puff.c b/gs/zlib/contrib/puff/puff.c
new file mode 100644
index 000000000..ce0cc405e
--- /dev/null
+++ b/gs/zlib/contrib/puff/puff.c
@@ -0,0 +1,837 @@
+/*
+ * puff.c
+ * Copyright (C) 2002-2004 Mark Adler
+ * For conditions of distribution and use, see copyright notice in puff.h
+ * version 1.8, 9 Jan 2004
+ *
+ * puff.c is a simple inflate written to be an unambiguous way to specify the
+ * deflate format.  It is not written for speed but rather simplicity.  As a
+ * side benefit, this code might actually be useful when small code is more
+ * important than speed, such as bootstrap applications.  For typical deflate
+ * data, zlib's inflate() is about four times as fast as puff().  zlib's
+ * inflate compiles to around 20K on my machine, whereas puff.c compiles to
+ * around 4K on my machine (a PowerPC using GNU cc).  If the faster decode()
+ * function here is used, then puff() is only twice as slow as zlib's
+ * inflate().
+ *
+ * All dynamically allocated memory comes from the stack.  The stack required
+ * is less than 2K bytes.  This code is compatible with 16-bit int's and
+ * assumes that long's are at least 32 bits.  puff.c uses the short data type,
+ * assumed to be 16 bits, for arrays in order to to conserve memory.  The code
+ * works whether integers are stored big endian or little endian.
+ *
+ * In the comments below are "Format notes" that describe the inflate process
+ * and document some of the less obvious aspects of the format.  This source
+ * code is meant to supplement RFC 1951, which formally describes the deflate
+ * format:
+ *
+ *    http://www.zlib.org/rfc-deflate.html
+ */
+
+/*
+ * Change history:
+ *
+ * 1.0  10 Feb 2002     - First version
+ * 1.1  17 Feb 2002     - Clarifications of some comments and notes
+ *                      - Update puff() dest and source pointers on negative
+ *                        errors to facilitate debugging deflators
+ *                      - Remove longest from struct huffman -- not needed
+ *                      - Simplify offs[] index in construct()
+ *                      - Add input size and checking, using longjmp() to
+ *                        maintain easy readability
+ *                      - Use short data type for large arrays
+ *                      - Use pointers instead of long to specify source and
+ *                        destination sizes to avoid arbitrary 4 GB limits
+ * 1.2  17 Mar 2002     - Add faster version of decode(), doubles speed (!),
+ *                        but leave simple version for readabilty
+ *                      - Make sure invalid distances detected if pointers
+ *                        are 16 bits
+ *                      - Fix fixed codes table error
+ *                      - Provide a scanning mode for determining size of
+ *                        uncompressed data
+ * 1.3  20 Mar 2002     - Go back to lengths for puff() parameters [Jean-loup]
+ *                      - Add a puff.h file for the interface
+ *                      - Add braces in puff() for else do [Jean-loup]
+ *                      - Use indexes instead of pointers for readability
+ * 1.4  31 Mar 2002     - Simplify construct() code set check
+ *                      - Fix some comments
+ *                      - Add FIXLCODES #define
+ * 1.5   6 Apr 2002     - Minor comment fixes
+ * 1.6   7 Aug 2002     - Minor format changes
+ * 1.7   3 Mar 2003     - Added test code for distribution
+ *                      - Added zlib-like license
+ * 1.8   9 Jan 2004     - Added some comments on no distance codes case
+ */
+
+#include <setjmp.h>             /* for setjmp(), longjmp(), and jmp_buf */
+#include "puff.h"               /* prototype for puff() */
+
+#define local static            /* for local function definitions */
+#define NIL ((unsigned char *)0)        /* for no output option */
+
+/*
+ * Maximums for allocations and loops.  It is not useful to change these --
+ * they are fixed by the deflate format.
+ */
+#define MAXBITS 15              /* maximum bits in a code */
+#define MAXLCODES 286           /* maximum number of literal/length codes */
+#define MAXDCODES 30            /* maximum number of distance codes */
+#define MAXCODES (MAXLCODES+MAXDCODES)  /* maximum codes lengths to read */
+#define FIXLCODES 288           /* number of fixed literal/length codes */
+
+/* input and output state */
+struct state {
+    /* output state */
+    unsigned char *out;         /* output buffer */
+    unsigned long outlen;       /* available space at out */
+    unsigned long outcnt;       /* bytes written to out so far */
+
+    /* input state */
+    unsigned char *in;          /* input buffer */
+    unsigned long inlen;        /* available input at in */
+    unsigned long incnt;        /* bytes read so far */
+    int bitbuf;                 /* bit buffer */
+    int bitcnt;                 /* number of bits in bit buffer */
+
+    /* input limit error return state for bits() and decode() */
+    jmp_buf env;
+};
+
+/*
+ * Return need bits from the input stream.  This always leaves less than
+ * eight bits in the buffer.  bits() works properly for need == 0.
+ *
+ * Format notes:
+ *
+ * - Bits are stored in bytes from the least significant bit to the most
+ *   significant bit.  Therefore bits are dropped from the bottom of the bit
+ *   buffer, using shift right, and new bytes are appended to the top of the
+ *   bit buffer, using shift left.
+ */
+local int bits(struct state *s, int need)
+{
+    long val;           /* bit accumulator (can use up to 20 bits) */
+
+    /* load at least need bits into val */
+    val = s->bitbuf;
+    while (s->bitcnt < need) {
+        if (s->incnt == s->inlen) longjmp(s->env, 1);   /* out of input */
+        val |= (long)(s->in[s->incnt++]) << s->bitcnt;  /* load eight bits */
+        s->bitcnt += 8;
+    }
+
+    /* drop need bits and update buffer, always zero to seven bits left */
+    s->bitbuf = (int)(val >> need);
+    s->bitcnt -= need;
+
+    /* return need bits, zeroing the bits above that */
+    return (int)(val & ((1L << need) - 1));
+}
+
+/*
+ * Process a stored block.
+ *
+ * Format notes:
+ *
+ * - After the two-bit stored block type (00), the stored block length and
+ *   stored bytes are byte-aligned for fast copying.  Therefore any leftover
+ *   bits in the byte that has the last bit of the type, as many as seven, are
+ *   discarded.  The value of the discarded bits are not defined and should not
+ *   be checked against any expectation.
+ *
+ * - The second inverted copy of the stored block length does not have to be
+ *   checked, but it's probably a good idea to do so anyway.
+ *
+ * - A stored block can have zero length.  This is sometimes used to byte-align
+ *   subsets of the compressed data for random access or partial recovery.
+ */
+local int stored(struct state *s)
+{
+    unsigned len;       /* length of stored block */
+
+    /* discard leftover bits from current byte (assumes s->bitcnt < 8) */
+    s->bitbuf = 0;
+    s->bitcnt = 0;
+
+    /* get length and check against its one's complement */
+    if (s->incnt + 4 > s->inlen) return 2;      /* not enough input */
+    len = s->in[s->incnt++];
+    len |= s->in[s->incnt++] << 8;
+    if (s->in[s->incnt++] != (~len & 0xff) ||
+        s->in[s->incnt++] != ((~len >> 8) & 0xff))
+        return -2;                              /* didn't match complement! */
+
+    /* copy len bytes from in to out */
+    if (s->incnt + len > s->inlen) return 2;    /* not enough input */
+    if (s->out != NIL) {
+        if (s->outcnt + len > s->outlen)
+            return 1;                           /* not enough output space */
+        while (len--)
+            s->out[s->outcnt++] = s->in[s->incnt++];
+    }
+    else {                                      /* just scanning */
+        s->outcnt += len;
+        s->incnt += len;
+    }
+
+    /* done with a valid stored block */
+    return 0;
+}
+
+/*
+ * Huffman code decoding tables.  count[1..MAXBITS] is the number of symbols of
+ * each length, which for a canonical code are stepped through in order.
+ * symbol[] are the symbol values in canonical order, where the number of
+ * entries is the sum of the counts in count[].  The decoding process can be
+ * seen in the function decode() below.
+ */
+struct huffman {
+    short *count;       /* number of symbols of each length */
+    short *symbol;      /* canonically ordered symbols */
+};
+
+/*
+ * Decode a code from the stream s using huffman table h.  Return the symbol or
+ * a negative value if there is an error.  If all of the lengths are zero, i.e.
+ * an empty code, or if the code is incomplete and an invalid code is received,
+ * then -9 is returned after reading MAXBITS bits.
+ *
+ * Format notes:
+ *
+ * - The codes as stored in the compressed data are bit-reversed relative to
+ *   a simple integer ordering of codes of the same lengths.  Hence below the
+ *   bits are pulled from the compressed data one at a time and used to
+ *   build the code value reversed from what is in the stream in order to
+ *   permit simple integer comparisons for decoding.  A table-based decoding
+ *   scheme (as used in zlib) does not need to do this reversal.
+ *
+ * - The first code for the shortest length is all zeros.  Subsequent codes of
+ *   the same length are simply integer increments of the previous code.  When
+ *   moving up a length, a zero bit is appended to the code.  For a complete
+ *   code, the last code of the longest length will be all ones.
+ *
+ * - Incomplete codes are handled by this decoder, since they are permitted
+ *   in the deflate format.  See the format notes for fixed() and dynamic().
+ */
+#ifdef SLOW
+local int decode(struct state *s, struct huffman *h)
+{
+    int len;            /* current number of bits in code */
+    int code;           /* len bits being decoded */
+    int first;          /* first code of length len */
+    int count;          /* number of codes of length len */
+    int index;          /* index of first code of length len in symbol table */
+
+    code = first = index = 0;
+    for (len = 1; len <= MAXBITS; len++) {
+        code |= bits(s, 1);             /* get next bit */
+        count = h->count[len];
+        if (code < first + count)       /* if length len, return symbol */
+            return h->symbol[index + (code - first)];
+        index += count;                 /* else update for next length */
+        first += count;
+        first <<= 1;
+        code <<= 1;
+    }
+    return -9;                          /* ran out of codes */
+}
+
+/*
+ * A faster version of decode() for real applications of this code.   It's not
+ * as readable, but it makes puff() twice as fast.  And it only makes the code
+ * a few percent larger.
+ */
+#else /* !SLOW */
+local int decode(struct state *s, struct huffman *h)
+{
+    int len;            /* current number of bits in code */
+    int code;           /* len bits being decoded */
+    int first;          /* first code of length len */
+    int count;          /* number of codes of length len */
+    int index;          /* index of first code of length len in symbol table */
+    int bitbuf;         /* bits from stream */
+    int left;           /* bits left in next or left to process */
+    short *next;        /* next number of codes */
+
+    bitbuf = s->bitbuf;
+    left = s->bitcnt;
+    code = first = index = 0;
+    len = 1;
+    next = h->count + 1;
+    while (1) {
+        while (left--) {
+            code |= bitbuf & 1;
+            bitbuf >>= 1;
+            count = *next++;
+            if (code < first + count) { /* if length len, return symbol */
+                s->bitbuf = bitbuf;
+                s->bitcnt = (s->bitcnt - len) & 7;
+                return h->symbol[index + (code - first)];
+            }
+            index += count;             /* else update for next length */
+            first += count;
+            first <<= 1;
+            code <<= 1;
+            len++;
+        }
+        left = (MAXBITS+1) - len;
+        if (left == 0) break;
+        if (s->incnt == s->inlen) longjmp(s->env, 1);   /* out of input */
+        bitbuf = s->in[s->incnt++];
+        if (left > 8) left = 8;
+    }
+    return -9;                          /* ran out of codes */
+}
+#endif /* SLOW */
+
+/*
+ * Given the list of code lengths length[0..n-1] representing a canonical
+ * Huffman code for n symbols, construct the tables required to decode those
+ * codes.  Those tables are the number of codes of each length, and the symbols
+ * sorted by length, retaining their original order within each length.  The
+ * return value is zero for a complete code set, negative for an over-
+ * subscribed code set, and positive for an incomplete code set.  The tables
+ * can be used if the return value is zero or positive, but they cannot be used
+ * if the return value is negative.  If the return value is zero, it is not
+ * possible for decode() using that table to return an error--any stream of
+ * enough bits will resolve to a symbol.  If the return value is positive, then
+ * it is possible for decode() using that table to return an error for received
+ * codes past the end of the incomplete lengths.
+ *
+ * Not used by decode(), but used for error checking, h->count[0] is the number
+ * of the n symbols not in the code.  So n - h->count[0] is the number of
+ * codes.  This is useful for checking for incomplete codes that have more than
+ * one symbol, which is an error in a dynamic block.
+ *
+ * Assumption: for all i in 0..n-1, 0 <= length[i] <= MAXBITS
+ * This is assured by the construction of the length arrays in dynamic() and
+ * fixed() and is not verified by construct().
+ *
+ * Format notes:
+ *
+ * - Permitted and expected examples of incomplete codes are one of the fixed
+ *   codes and any code with a single symbol which in deflate is coded as one
+ *   bit instead of zero bits.  See the format notes for fixed() and dynamic().
+ *
+ * - Within a given code length, the symbols are kept in ascending order for
+ *   the code bits definition.
+ */
+local int construct(struct huffman *h, short *length, int n)
+{
+    int symbol;         /* current symbol when stepping through length[] */
+    int len;            /* current length when stepping through h->count[] */
+    int left;           /* number of possible codes left of current length */
+    short offs[MAXBITS+1];      /* offsets in symbol table for each length */
+
+    /* count number of codes of each length */
+    for (len = 0; len <= MAXBITS; len++)
+        h->count[len] = 0;
+    for (symbol = 0; symbol < n; symbol++)
+        (h->count[length[symbol]])++;   /* assumes lengths are within bounds */
+    if (h->count[0] == n)               /* no codes! */
+        return 0;                       /* complete, but decode() will fail */
+
+    /* check for an over-subscribed or incomplete set of lengths */
+    left = 1;                           /* one possible code of zero length */
+    for (len = 1; len <= MAXBITS; len++) {
+        left <<= 1;                     /* one more bit, double codes left */
+        left -= h->count[len];          /* deduct count from possible codes */
+        if (left < 0) return left;      /* over-subscribed--return negative */
+    }                                   /* left > 0 means incomplete */
+
+    /* generate offsets into symbol table for each length for sorting */
+    offs[1] = 0;
+    for (len = 1; len < MAXBITS; len++)
+        offs[len + 1] = offs[len] + h->count[len];
+
+    /*
+     * put symbols in table sorted by length, by symbol order within each
+     * length
+     */
+    for (symbol = 0; symbol < n; symbol++)
+        if (length[symbol] != 0)
+            h->symbol[offs[length[symbol]]++] = symbol;
+
+    /* return zero for complete set, positive for incomplete set */
+    return left;
+}
+
+/*
+ * Decode literal/length and distance codes until an end-of-block code.
+ *
+ * Format notes:
+ *
+ * - Compressed data that is after the block type if fixed or after the code
+ *   description if dynamic is a combination of literals and length/distance
+ *   pairs terminated by and end-of-block code.  Literals are simply Huffman
+ *   coded bytes.  A length/distance pair is a coded length followed by a
+ *   coded distance to represent a string that occurs earlier in the
+ *   uncompressed data that occurs again at the current location.
+ *
+ * - Literals, lengths, and the end-of-block code are combined into a single
+ *   code of up to 286 symbols.  They are 256 literals (0..255), 29 length
+ *   symbols (257..285), and the end-of-block symbol (256).
+ *
+ * - There are 256 possible lengths (3..258), and so 29 symbols are not enough
+ *   to represent all of those.  Lengths 3..10 and 258 are in fact represented
+ *   by just a length symbol.  Lengths 11..257 are represented as a symbol and
+ *   some number of extra bits that are added as an integer to the base length
+ *   of the length symbol.  The number of extra bits is determined by the base
+ *   length symbol.  These are in the static arrays below, lens[] for the base
+ *   lengths and lext[] for the corresponding number of extra bits.
+ *
+ * - The reason that 258 gets its own symbol is that the longest length is used
+ *   often in highly redundant files.  Note that 258 can also be coded as the
+ *   base value 227 plus the maximum extra value of 31.  While a good deflate
+ *   should never do this, it is not an error, and should be decoded properly.
+ *
+ * - If a length is decoded, including its extra bits if any, then it is
+ *   followed a distance code.  There are up to 30 distance symbols.  Again
+ *   there are many more possible distances (1..32768), so extra bits are added
+ *   to a base value represented by the symbol.  The distances 1..4 get their
+ *   own symbol, but the rest require extra bits.  The base distances and
+ *   corresponding number of extra bits are below in the static arrays dist[]
+ *   and dext[].
+ *
+ * - Literal bytes are simply written to the output.  A length/distance pair is
+ *   an instruction to copy previously uncompressed bytes to the output.  The
+ *   copy is from distance bytes back in the output stream, copying for length
+ *   bytes.
+ *
+ * - Distances pointing before the beginning of the output data are not
+ *   permitted.
+ *
+ * - Overlapped copies, where the length is greater than the distance, are
+ *   allowed and common.  For example, a distance of one and a length of 258
+ *   simply copies the last byte 258 times.  A distance of four and a length of
+ *   twelve copies the last four bytes three times.  A simple forward copy
+ *   ignoring whether the length is greater than the distance or not implements
+ *   this correctly.  You should not use memcpy() since its behavior is not
+ *   defined for overlapped arrays.  You should not use memmove() or bcopy()
+ *   since though their behavior -is- defined for overlapping arrays, it is
+ *   defined to do the wrong thing in this case.
+ */
+local int codes(struct state *s,
+                struct huffman *lencode,
+                struct huffman *distcode)
+{
+    int symbol;         /* decoded symbol */
+    int len;            /* length for copy */
+    unsigned dist;      /* distance for copy */
+    static const short lens[29] = { /* Size base for length codes 257..285 */
+        3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
+        35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258};
+    static const short lext[29] = { /* Extra bits for length codes 257..285 */
+        0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
+        3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0};
+    static const short dists[30] = { /* Offset base for distance codes 0..29 */
+        1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
+        257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
+        8193, 12289, 16385, 24577};
+    static const short dext[30] = { /* Extra bits for distance codes 0..29 */
+        0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
+        7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
+        12, 12, 13, 13};
+
+    /* decode literals and length/distance pairs */
+    do {
+        symbol = decode(s, lencode);
+        if (symbol < 0) return symbol;  /* invalid symbol */
+        if (symbol < 256) {             /* literal: symbol is the byte */
+            /* write out the literal */
+            if (s->out != NIL) {
+                if (s->outcnt == s->outlen) return 1;
+                s->out[s->outcnt] = symbol;
+            }
+            s->outcnt++;
+        }
+        else if (symbol > 256) {        /* length */
+            /* get and compute length */
+            symbol -= 257;
+            if (symbol >= 29) return -9;        /* invalid fixed code */
+            len = lens[symbol] + bits(s, lext[symbol]);
+
+            /* get and check distance */
+            symbol = decode(s, distcode);
+            if (symbol < 0) return symbol;      /* invalid symbol */
+            dist = dists[symbol] + bits(s, dext[symbol]);
+            if (dist > s->outcnt)
+                return -10;     /* distance too far back */
+
+            /* copy length bytes from distance bytes back */
+            if (s->out != NIL) {
+                if (s->outcnt + len > s->outlen) return 1;
+                while (len--) {
+                    s->out[s->outcnt] = s->out[s->outcnt - dist];
+                    s->outcnt++;
+                }
+            }
+            else
+                s->outcnt += len;
+        }
+    } while (symbol != 256);            /* end of block symbol */
+
+    /* done with a valid fixed or dynamic block */
+    return 0;
+}
+
+/*
+ * Process a fixed codes block.
+ *
+ * Format notes:
+ *
+ * - This block type can be useful for compressing small amounts of data for
+ *   which the size of the code descriptions in a dynamic block exceeds the
+ *   benefit of custom codes for that block.  For fixed codes, no bits are
+ *   spent on code descriptions.  Instead the code lengths for literal/length
+ *   codes and distance codes are fixed.  The specific lengths for each symbol
+ *   can be seen in the "for" loops below.
+ *
+ * - The literal/length code is complete, but has two symbols that are invalid
+ *   and should result in an error if received.  This cannot be implemented
+ *   simply as an incomplete code since those two symbols are in the "middle"
+ *   of the code.  They are eight bits long and the longest literal/length\
+ *   code is nine bits.  Therefore the code must be constructed with those
+ *   symbols, and the invalid symbols must be detected after decoding.
+ *
+ * - The fixed distance codes also have two invalid symbols that should result
+ *   in an error if received.  Since all of the distance codes are the same
+ *   length, this can be implemented as an incomplete code.  Then the invalid
+ *   codes are detected while decoding.
+ */
+local int fixed(struct state *s)
+{
+    static int virgin = 1;
+    static short lencnt[MAXBITS+1], lensym[FIXLCODES];
+    static short distcnt[MAXBITS+1], distsym[MAXDCODES];
+    static struct huffman lencode = {lencnt, lensym};
+    static struct huffman distcode = {distcnt, distsym};
+
+    /* build fixed huffman tables if first call (may not be thread safe) */
+    if (virgin) {
+        int symbol;
+        short lengths[FIXLCODES];
+
+        /* literal/length table */
+        for (symbol = 0; symbol < 144; symbol++)
+            lengths[symbol] = 8;
+        for (; symbol < 256; symbol++)
+            lengths[symbol] = 9;
+        for (; symbol < 280; symbol++)
+            lengths[symbol] = 7;
+        for (; symbol < FIXLCODES; symbol++)
+            lengths[symbol] = 8;
+        construct(&lencode, lengths, FIXLCODES);
+
+        /* distance table */
+        for (symbol = 0; symbol < MAXDCODES; symbol++)
+            lengths[symbol] = 5;
+        construct(&distcode, lengths, MAXDCODES);
+
+        /* do this just once */
+        virgin = 0;
+    }
+
+    /* decode data until end-of-block code */
+    return codes(s, &lencode, &distcode);
+}
+
+/*
+ * Process a dynamic codes block.
+ *
+ * Format notes:
+ *
+ * - A dynamic block starts with a description of the literal/length and
+ *   distance codes for that block.  New dynamic blocks allow the compressor to
+ *   rapidly adapt to changing data with new codes optimized for that data.
+ *
+ * - The codes used by the deflate format are "canonical", which means that
+ *   the actual bits of the codes are generated in an unambiguous way simply
+ *   from the number of bits in each code.  Therefore the code descriptions
+ *   are simply a list of code lengths for each symbol.
+ *
+ * - The code lengths are stored in order for the symbols, so lengths are
+ *   provided for each of the literal/length symbols, and for each of the
+ *   distance symbols.
+ *
+ * - If a symbol is not used in the block, this is represented by a zero as
+ *   as the code length.  This does not mean a zero-length code, but rather
+ *   that no code should be created for this symbol.  There is no way in the
+ *   deflate format to represent a zero-length code.
+ *
+ * - The maximum number of bits in a code is 15, so the possible lengths for
+ *   any code are 1..15.
+ *
+ * - The fact that a length of zero is not permitted for a code has an
+ *   interesting consequence.  Normally if only one symbol is used for a given
+ *   code, then in fact that code could be represented with zero bits.  However
+ *   in deflate, that code has to be at least one bit.  So for example, if
+ *   only a single distance base symbol appears in a block, then it will be
+ *   represented by a single code of length one, in particular one 0 bit.  This
+ *   is an incomplete code, since if a 1 bit is received, it has no meaning,
+ *   and should result in an error.  So incomplete distance codes of one symbol
+ *   should be permitted, and the receipt of invalid codes should be handled.
+ *
+ * - It is also possible to have a single literal/length code, but that code
+ *   must be the end-of-block code, since every dynamic block has one.  This
+ *   is not the most efficient way to create an empty block (an empty fixed
+ *   block is fewer bits), but it is allowed by the format.  So incomplete
+ *   literal/length codes of one symbol should also be permitted.
+ *
+ * - If there are only literal codes and no lengths, then there are no distance
+ *   codes.  This is represented by one distance code with zero bits.
+ *
+ * - The list of up to 286 length/literal lengths and up to 30 distance lengths
+ *   are themselves compressed using Huffman codes and run-length encoding.  In
+ *   the list of code lengths, a 0 symbol means no code, a 1..15 symbol means
+ *   that length, and the symbols 16, 17, and 18 are run-length instructions.
+ *   Each of 16, 17, and 18 are follwed by extra bits to define the length of
+ *   the run.  16 copies the last length 3 to 6 times.  17 represents 3 to 10
+ *   zero lengths, and 18 represents 11 to 138 zero lengths.  Unused symbols
+ *   are common, hence the special coding for zero lengths.
+ *
+ * - The symbols for 0..18 are Huffman coded, and so that code must be
+ *   described first.  This is simply a sequence of up to 19 three-bit values
+ *   representing no code (0) or the code length for that symbol (1..7).
+ *
+ * - A dynamic block starts with three fixed-size counts from which is computed
+ *   the number of literal/length code lengths, the number of distance code
+ *   lengths, and the number of code length code lengths (ok, you come up with
+ *   a better name!) in the code descriptions.  For the literal/length and
+ *   distance codes, lengths after those provided are considered zero, i.e. no
+ *   code.  The code length code lengths are received in a permuted order (see
+ *   the order[] array below) to make a short code length code length list more
+ *   likely.  As it turns out, very short and very long codes are less likely
+ *   to be seen in a dynamic code description, hence what may appear initially
+ *   to be a peculiar ordering.
+ *
+ * - Given the number of literal/length code lengths (nlen) and distance code
+ *   lengths (ndist), then they are treated as one long list of nlen + ndist
+ *   code lengths.  Therefore run-length coding can and often does cross the
+ *   boundary between the two sets of lengths.
+ *
+ * - So to summarize, the code description at the start of a dynamic block is
+ *   three counts for the number of code lengths for the literal/length codes,
+ *   the distance codes, and the code length codes.  This is followed by the
+ *   code length code lengths, three bits each.  This is used to construct the
+ *   code length code which is used to read the remainder of the lengths.  Then
+ *   the literal/length code lengths and distance lengths are read as a single
+ *   set of lengths using the code length codes.  Codes are constructed from
+ *   the resulting two sets of lengths, and then finally you can start
+ *   decoding actual compressed data in the block.
+ *
+ * - For reference, a "typical" size for the code description in a dynamic
+ *   block is around 80 bytes.
+ */
+local int dynamic(struct state *s)
+{
+    int nlen, ndist, ncode;             /* number of lengths in descriptor */
+    int index;                          /* index of lengths[] */
+    int err;                            /* construct() return value */
+    short lengths[MAXCODES];            /* descriptor code lengths */
+    short lencnt[MAXBITS+1], lensym[MAXLCODES];         /* lencode memory */
+    short distcnt[MAXBITS+1], distsym[MAXDCODES];       /* distcode memory */
+    struct huffman lencode = {lencnt, lensym};          /* length code */
+    struct huffman distcode = {distcnt, distsym};       /* distance code */
+    static const short order[19] =      /* permutation of code length codes */
+        {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
+
+    /* get number of lengths in each table, check lengths */
+    nlen = bits(s, 5) + 257;
+    ndist = bits(s, 5) + 1;
+    ncode = bits(s, 4) + 4;
+    if (nlen > MAXLCODES || ndist > MAXDCODES)
+        return -3;                      /* bad counts */
+
+    /* read code length code lengths (really), missing lengths are zero */
+    for (index = 0; index < ncode; index++)
+        lengths[order[index]] = bits(s, 3);
+    for (; index < 19; index++)
+        lengths[order[index]] = 0;
+
+    /* build huffman table for code lengths codes (use lencode temporarily) */
+    err = construct(&lencode, lengths, 19);
+    if (err != 0) return -4;            /* require complete code set here */
+
+    /* read length/literal and distance code length tables */
+    index = 0;
+    while (index < nlen + ndist) {
+        int symbol;             /* decoded value */
+        int len;                /* last length to repeat */
+
+        symbol = decode(s, &lencode);
+        if (symbol < 16)                /* length in 0..15 */
+            lengths[index++] = symbol;
+        else {                          /* repeat instruction */
+            len = 0;                    /* assume repeating zeros */
+            if (symbol == 16) {         /* repeat last length 3..6 times */
+                if (index == 0) return -5;      /* no last length! */
+                len = lengths[index - 1];       /* last length */
+                symbol = 3 + bits(s, 2);
+            }
+            else if (symbol == 17)      /* repeat zero 3..10 times */
+                symbol = 3 + bits(s, 3);
+            else                        /* == 18, repeat zero 11..138 times */
+                symbol = 11 + bits(s, 7);
+            if (index + symbol > nlen + ndist)
+                return -6;              /* too many lengths! */
+            while (symbol--)            /* repeat last or zero symbol times */
+                lengths[index++] = len;
+        }
+    }
+
+    /* build huffman table for literal/length codes */
+    err = construct(&lencode, lengths, nlen);
+    if (err < 0 || (err > 0 && nlen - lencode.count[0] != 1))
+        return -7;      /* only allow incomplete codes if just one code */
+
+    /* build huffman table for distance codes */
+    err = construct(&distcode, lengths + nlen, ndist);
+    if (err < 0 || (err > 0 && ndist - distcode.count[0] != 1))
+        return -8;      /* only allow incomplete codes if just one code */
+
+    /* decode data until end-of-block code */
+    return codes(s, &lencode, &distcode);
+}
+
+/*
+ * Inflate source to dest.  On return, destlen and sourcelen are updated to the
+ * size of the uncompressed data and the size of the deflate data respectively.
+ * On success, the return value of puff() is zero.  If there is an error in the
+ * source data, i.e. it is not in the deflate format, then a negative value is
+ * returned.  If there is not enough input available or there is not enough
+ * output space, then a positive error is returned.  In that case, destlen and
+ * sourcelen are not updated to facilitate retrying from the beginning with the
+ * provision of more input data or more output space.  In the case of invalid
+ * inflate data (a negative error), the dest and source pointers are updated to
+ * facilitate the debugging of deflators.
+ *
+ * puff() also has a mode to determine the size of the uncompressed output with
+ * no output written.  For this dest must be (unsigned char *)0.  In this case,
+ * the input value of *destlen is ignored, and on return *destlen is set to the
+ * size of the uncompressed output.
+ *
+ * The return codes are:
+ *
+ *   2:  available inflate data did not terminate
+ *   1:  output space exhausted before completing inflate
+ *   0:  successful inflate
+ *  -1:  invalid block type (type == 3)
+ *  -2:  stored block length did not match one's complement
+ *  -3:  dynamic block code description: too many length or distance codes
+ *  -4:  dynamic block code description: code lengths codes incomplete
+ *  -5:  dynamic block code description: repeat lengths with no first length
+ *  -6:  dynamic block code description: repeat more than specified lengths
+ *  -7:  dynamic block code description: invalid literal/length code lengths
+ *  -8:  dynamic block code description: invalid distance code lengths
+ *  -9:  invalid literal/length or distance code in fixed or dynamic block
+ * -10:  distance is too far back in fixed or dynamic block
+ *
+ * Format notes:
+ *
+ * - Three bits are read for each block to determine the kind of block and
+ *   whether or not it is the last block.  Then the block is decoded and the
+ *   process repeated if it was not the last block.
+ *
+ * - The leftover bits in the last byte of the deflate data after the last
+ *   block (if it was a fixed or dynamic block) are undefined and have no
+ *   expected values to check.
+ */
+int puff(unsigned char *dest,           /* pointer to destination pointer */
+         unsigned long *destlen,        /* amount of output space */
+         unsigned char *source,         /* pointer to source data pointer */
+         unsigned long *sourcelen)      /* amount of input available */
+{
+    struct state s;             /* input/output state */
+    int last, type;             /* block information */
+    int err;                    /* return value */
+
+    /* initialize output state */
+    s.out = dest;
+    s.outlen = *destlen;                /* ignored if dest is NIL */
+    s.outcnt = 0;
+
+    /* initialize input state */
+    s.in = source;
+    s.inlen = *sourcelen;
+    s.incnt = 0;
+    s.bitbuf = 0;
+    s.bitcnt = 0;
+
+    /* return if bits() or decode() tries to read past available input */
+    if (setjmp(s.env) != 0)             /* if came back here via longjmp() */
+        err = 2;                        /* then skip do-loop, return error */
+    else {
+        /* process blocks until last block or error */
+        do {
+            last = bits(&s, 1);         /* one if last block */
+            type = bits(&s, 2);         /* block type 0..3 */
+            err = type == 0 ? stored(&s) :
+                  (type == 1 ? fixed(&s) :
+                   (type == 2 ? dynamic(&s) :
+                    -1));               /* type == 3, invalid */
+            if (err != 0) break;        /* return with error */
+        } while (!last);
+    }
+
+    /* update the lengths and return */
+    if (err <= 0) {
+        *destlen = s.outcnt;
+        *sourcelen = s.incnt;
+    }
+    return err;
+}
+
+#ifdef TEST
+/* Example of how to use puff() */
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+local unsigned char *yank(char *name, unsigned long *len)
+{
+    unsigned long size;
+    unsigned char *buf;
+    FILE *in;
+    struct stat s;
+
+    *len = 0;
+    if (stat(name, &s)) return NULL;
+    if ((s.st_mode & S_IFMT) != S_IFREG) return NULL;
+    size = (unsigned long)(s.st_size);
+    if (size == 0 || (off_t)size != s.st_size) return NULL;
+    in = fopen(name, "r");
+    if (in == NULL) return NULL;
+    buf = malloc(size);
+    if (buf != NULL && fread(buf, 1, size, in) != size) {
+        free(buf);
+        buf = NULL;
+    }
+    fclose(in);
+    *len = size;
+    return buf;
+}
+
+int main(int argc, char **argv)
+{
+    int ret;
+    unsigned char *source;
+    unsigned long len, sourcelen, destlen;
+
+    if (argc < 2) return 2;
+    source = yank(argv[1], &len);
+    if (source == NULL) return 2;
+    sourcelen = len;
+    ret = puff(NIL, &destlen, source, &sourcelen);
+    if (ret)
+        printf("puff() failed with return code %d\n", ret);
+    else {
+        printf("puff() succeeded uncompressing %lu bytes\n", destlen);
+        if (sourcelen < len) printf("%lu compressed bytes unused\n",
+                                    len - sourcelen);
+    }
+    free(source);
+    return ret;
+}
+#endif
diff --git a/gs/zlib/contrib/puff/puff.h b/gs/zlib/contrib/puff/puff.h
new file mode 100644
index 000000000..ef612520b
--- /dev/null
+++ b/gs/zlib/contrib/puff/puff.h
@@ -0,0 +1,31 @@
+/* puff.h
+  Copyright (C) 2002, 2003 Mark Adler, all rights reserved
+  version 1.7, 3 Mar 2002
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the author be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+
+  Mark Adler    madler@alumni.caltech.edu
+ */
+
+
+/*
+ * See puff.c for purpose and usage.
+ */
+int puff(unsigned char *dest,           /* pointer to destination pointer */
+         unsigned long *destlen,        /* amount of output space */
+         unsigned char *source,         /* pointer to source data pointer */
+         unsigned long *sourcelen);     /* amount of input available */
diff --git a/gs/zlib/contrib/puff/zeros.raw b/gs/zlib/contrib/puff/zeros.raw
new file mode 100644
index 000000000..637b7be6f
--- /dev/null
+++ b/gs/zlib/contrib/puff/zeros.raw
diff --git a/gs/zlib/contrib/testzlib/testzlib.c b/gs/zlib/contrib/testzlib/testzlib.c
new file mode 100644
index 000000000..e5574f45e
--- /dev/null
+++ b/gs/zlib/contrib/testzlib/testzlib.c
@@ -0,0 +1,275 @@
+#include <stdio.h>

+#include <stdlib.h>

+#include <windows.h>

+

+#include "zlib.h"

+

+

+void MyDoMinus64(LARGE_INTEGER *R,LARGE_INTEGER A,LARGE_INTEGER B)

+{

+    R->HighPart = A.HighPart - B.HighPart;

+    if (A.LowPart >= B.LowPart)

+        R->LowPart = A.LowPart - B.LowPart;

+    else

+    {

+        R->LowPart = A.LowPart - B.LowPart;

+        R->HighPart --;

+    }

+}

+

+#ifdef _M_X64

+// see http://msdn2.microsoft.com/library/twchhe95(en-us,vs.80).aspx for __rdtsc

+unsigned __int64 __rdtsc(void);

+void BeginCountRdtsc(LARGE_INTEGER * pbeginTime64)

+{

+ //   printf("rdtsc = %I64x\n",__rdtsc());

+   pbeginTime64->QuadPart=__rdtsc();

+}

+

+LARGE_INTEGER GetResRdtsc(LARGE_INTEGER beginTime64,BOOL fComputeTimeQueryPerf)

+{

+    LARGE_INTEGER LIres;

+    unsigned _int64 res=__rdtsc()-((unsigned _int64)(beginTime64.QuadPart));

+    LIres.QuadPart=res;

+   // printf("rdtsc = %I64x\n",__rdtsc());

+    return LIres;

+}

+#else

+#ifdef _M_IX86

+void myGetRDTSC32(LARGE_INTEGER * pbeginTime64)

+{

+    DWORD dwEdx,dwEax;

+    _asm

+    {

+        rdtsc

+        mov dwEax,eax

+        mov dwEdx,edx

+    }

+    pbeginTime64->LowPart=dwEax;

+    pbeginTime64->HighPart=dwEdx;

+}

+

+void BeginCountRdtsc(LARGE_INTEGER * pbeginTime64)

+{

+    myGetRDTSC32(pbeginTime64);

+}

+

+LARGE_INTEGER GetResRdtsc(LARGE_INTEGER beginTime64,BOOL fComputeTimeQueryPerf)

+{

+    LARGE_INTEGER LIres,endTime64;

+    myGetRDTSC32(&endTime64);

+

+    LIres.LowPart=LIres.HighPart=0;

+    MyDoMinus64(&LIres,endTime64,beginTime64);

+    return LIres;

+}

+#else

+void myGetRDTSC32(LARGE_INTEGER * pbeginTime64)

+{

+}

+

+void BeginCountRdtsc(LARGE_INTEGER * pbeginTime64)

+{

+}

+

+LARGE_INTEGER GetResRdtsc(LARGE_INTEGER beginTime64,BOOL fComputeTimeQueryPerf)

+{

+    LARGE_INTEGER lr;

+    lr.QuadPart=0;

+    return lr;

+}

+#endif

+#endif

+

+void BeginCountPerfCounter(LARGE_INTEGER * pbeginTime64,BOOL fComputeTimeQueryPerf)

+{

+    if ((!fComputeTimeQueryPerf) || (!QueryPerformanceCounter(pbeginTime64)))

+    {

+        pbeginTime64->LowPart = GetTickCount();

+        pbeginTime64->HighPart = 0;

+    }

+}

+

+DWORD GetMsecSincePerfCounter(LARGE_INTEGER beginTime64,BOOL fComputeTimeQueryPerf)

+{

+    LARGE_INTEGER endTime64,ticksPerSecond,ticks;

+    DWORDLONG ticksShifted,tickSecShifted;

+    DWORD dwLog=16+0;

+    DWORD dwRet;

+    if ((!fComputeTimeQueryPerf) || (!QueryPerformanceCounter(&endTime64)))

+        dwRet = (GetTickCount() - beginTime64.LowPart)*1;

+    else

+    {

+        MyDoMinus64(&ticks,endTime64,beginTime64);

+        QueryPerformanceFrequency(&ticksPerSecond);

+

+    

+        {

+            ticksShifted = Int64ShrlMod32(*(DWORDLONG*)&ticks,dwLog);

+            tickSecShifted = Int64ShrlMod32(*(DWORDLONG*)&ticksPerSecond,dwLog);

+        

+        } 

+

+        dwRet = (DWORD)((((DWORD)ticksShifted)*1000)/(DWORD)(tickSecShifted));

+        dwRet *=1;

+    }

+    return dwRet;

+}

+

+int ReadFileMemory(const char* filename,long* plFileSize,void** pFilePtr)

+{

+    FILE* stream;

+    void* ptr;

+    int retVal=1;

+    stream=fopen(filename, "rb");

+    if (stream==NULL)

+        return 0;

+

+    fseek(stream,0,SEEK_END);

+

+    *plFileSize=ftell(stream);

+    fseek(stream,0,SEEK_SET);

+    ptr=malloc((*plFileSize)+1);

+    if (ptr==NULL)

+        retVal=0;

+    else

+    {

+        if (fread(ptr, 1, *plFileSize,stream) != (*plFileSize))

+            retVal=0;

+    }

+    fclose(stream);

+    *pFilePtr=ptr;

+    return retVal;

+}

+

+int main(int argc, char *argv[])

+{

+    int BlockSizeCompress=0x8000;

+    int BlockSizeUncompress=0x8000;

+    int cprLevel=Z_DEFAULT_COMPRESSION ;

+    long lFileSize;

+    unsigned char* FilePtr;

+    long lBufferSizeCpr;

+    long lBufferSizeUncpr;

+    long lCompressedSize=0;

+    unsigned char* CprPtr;

+    unsigned char* UncprPtr;

+    long lSizeCpr,lSizeUncpr;

+    DWORD dwGetTick,dwMsecQP;

+    LARGE_INTEGER li_qp,li_rdtsc,dwResRdtsc;

+

+    if (argc<=1)

+    {

+        printf("run TestZlib <File> [BlockSizeCompress] [BlockSizeUncompress] [compres. level]\n");

+        return 0;

+    }

+

+    if (ReadFileMemory(argv[1],&lFileSize,&FilePtr)==0)

+    {

+        printf("error reading %s\n",argv[1]);

+        return 1;

+    }

+    else printf("file %s read, %u bytes\n",argv[1],lFileSize);

+

+    if (argc>=3)

+        BlockSizeCompress=atol(argv[2]);

+

+    if (argc>=4)

+        BlockSizeUncompress=atol(argv[3]);

+

+    if (argc>=5)

+        cprLevel=(int)atol(argv[4]);

+

+    lBufferSizeCpr = lFileSize + (lFileSize/0x10) + 0x200;

+    lBufferSizeUncpr = lBufferSizeCpr;

+

+    CprPtr=(unsigned char*)malloc(lBufferSizeCpr + BlockSizeCompress);

+

+    BeginCountPerfCounter(&li_qp,TRUE);

+    dwGetTick=GetTickCount();

+    BeginCountRdtsc(&li_rdtsc);

+    {

+        z_stream zcpr;

+        int ret=Z_OK;

+        long lOrigToDo = lFileSize;

+        long lOrigDone = 0;

+        int step=0;

+        memset(&zcpr,0,sizeof(z_stream));

+        deflateInit(&zcpr,cprLevel);

+

+        zcpr.next_in = FilePtr;

+        zcpr.next_out = CprPtr;

+

+

+        do

+        {

+            long all_read_before = zcpr.total_in;

+            zcpr.avail_in = min(lOrigToDo,BlockSizeCompress);

+            zcpr.avail_out = BlockSizeCompress;

+            ret=deflate(&zcpr,(zcpr.avail_in==lOrigToDo) ? Z_FINISH : Z_SYNC_FLUSH);

+            lOrigDone += (zcpr.total_in-all_read_before);

+            lOrigToDo -= (zcpr.total_in-all_read_before);

+            step++;

+        } while (ret==Z_OK);

+

+        lSizeCpr=zcpr.total_out;

+        deflateEnd(&zcpr);

+        dwGetTick=GetTickCount()-dwGetTick;

+        dwMsecQP=GetMsecSincePerfCounter(li_qp,TRUE);

+        dwResRdtsc=GetResRdtsc(li_rdtsc,TRUE);

+        printf("total compress size = %u, in %u step\n",lSizeCpr,step);

+        printf("time = %u msec = %f sec\n",dwGetTick,dwGetTick/(double)1000.);

+        printf("defcpr time QP = %u msec = %f sec\n",dwMsecQP,dwMsecQP/(double)1000.);

+        printf("defcpr result rdtsc = %I64x\n\n",dwResRdtsc.QuadPart);

+    }

+

+    CprPtr=(unsigned char*)realloc(CprPtr,lSizeCpr);

+    UncprPtr=(unsigned char*)malloc(lBufferSizeUncpr + BlockSizeUncompress);

+

+    BeginCountPerfCounter(&li_qp,TRUE);

+    dwGetTick=GetTickCount();

+    BeginCountRdtsc(&li_rdtsc);

+    {

+        z_stream zcpr;

+        int ret=Z_OK;

+        long lOrigToDo = lSizeCpr;

+        long lOrigDone = 0;

+        int step=0;

+        memset(&zcpr,0,sizeof(z_stream));

+        inflateInit(&zcpr);

+

+        zcpr.next_in = CprPtr;

+        zcpr.next_out = UncprPtr;

+

+

+        do

+        {

+            long all_read_before = zcpr.total_in;

+            zcpr.avail_in = min(lOrigToDo,BlockSizeUncompress);

+            zcpr.avail_out = BlockSizeUncompress;

+            ret=inflate(&zcpr,Z_SYNC_FLUSH);

+            lOrigDone += (zcpr.total_in-all_read_before);

+            lOrigToDo -= (zcpr.total_in-all_read_before);

+            step++;

+        } while (ret==Z_OK);

+

+        lSizeUncpr=zcpr.total_out;

+        inflateEnd(&zcpr);

+        dwGetTick=GetTickCount()-dwGetTick;

+        dwMsecQP=GetMsecSincePerfCounter(li_qp,TRUE);

+        dwResRdtsc=GetResRdtsc(li_rdtsc,TRUE);

+        printf("total uncompress size = %u, in %u step\n",lSizeUncpr,step);

+        printf("time = %u msec = %f sec\n",dwGetTick,dwGetTick/(double)1000.);

+        printf("uncpr  time QP = %u msec = %f sec\n",dwMsecQP,dwMsecQP/(double)1000.);

+        printf("uncpr  result rdtsc = %I64x\n\n",dwResRdtsc.QuadPart);

+    }

+

+    if (lSizeUncpr==lFileSize)

+    {

+        if (memcmp(FilePtr,UncprPtr,lFileSize)==0)

+            printf("compare ok\n");

+

+    }

+

+    return 0;

+}

diff --git a/gs/zlib/contrib/testzlib/testzlib.txt b/gs/zlib/contrib/testzlib/testzlib.txt
new file mode 100644
index 000000000..62258f149
--- /dev/null
+++ b/gs/zlib/contrib/testzlib/testzlib.txt
@@ -0,0 +1,10 @@
+To build testzLib with Visual Studio 2005:

+

+copy to a directory file from :

+- root of zLib tree

+- contrib/testzlib

+- contrib/masmx86

+- contrib/masmx64

+- contrib/vstudio/vc7

+

+and open testzlib8.sln
\ No newline at end of file
diff --git a/gs/zlib/contrib/untgz/Makefile b/gs/zlib/contrib/untgz/Makefile
new file mode 100644
index 000000000..b54266fba
--- /dev/null
+++ b/gs/zlib/contrib/untgz/Makefile
@@ -0,0 +1,14 @@
+CC=cc
+CFLAGS=-g
+
+untgz: untgz.o ../../libz.a
+	$(CC) $(CFLAGS) -o untgz untgz.o -L../.. -lz
+
+untgz.o: untgz.c ../../zlib.h
+	$(CC) $(CFLAGS) -c -I../.. untgz.c
+
+../../libz.a:
+	cd ../..; ./configure; make
+
+clean:
+	rm -f untgz untgz.o *~
diff --git a/gs/zlib/contrib/untgz/Makefile.msc b/gs/zlib/contrib/untgz/Makefile.msc
new file mode 100644
index 000000000..77b860221
--- /dev/null
+++ b/gs/zlib/contrib/untgz/Makefile.msc
@@ -0,0 +1,17 @@
+CC=cl
+CFLAGS=-MD
+
+untgz.exe: untgz.obj ..\..\zlib.lib
+	$(CC) $(CFLAGS) untgz.obj ..\..\zlib.lib
+
+untgz.obj: untgz.c ..\..\zlib.h
+	$(CC) $(CFLAGS) -c -I..\.. untgz.c
+
+..\..\zlib.lib:
+	cd ..\..
+	$(MAKE) -f win32\makefile.msc
+	cd contrib\untgz
+
+clean:
+	-del untgz.obj
+	-del untgz.exe
diff --git a/gs/zlib/contrib/untgz/untgz.c b/gs/zlib/contrib/untgz/untgz.c
new file mode 100644
index 000000000..2c391e598
--- /dev/null
+++ b/gs/zlib/contrib/untgz/untgz.c
@@ -0,0 +1,674 @@
+/*
+ * untgz.c -- Display contents and extract files from a gzip'd TAR file
+ *
+ * written by Pedro A. Aranda Gutierrez <paag@tid.es>
+ * adaptation to Unix by Jean-loup Gailly <jloup@gzip.org>
+ * various fixes by Cosmin Truta <cosmint@cs.ubbcluj.ro>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <errno.h>
+
+#include "zlib.h"
+
+#ifdef unix
+#  include <unistd.h>
+#else
+#  include <direct.h>
+#  include <io.h>
+#endif
+
+#ifdef WIN32
+#include <windows.h>
+#  ifndef F_OK
+#    define F_OK  0
+#  endif
+#  define mkdir(dirname,mode)   _mkdir(dirname)
+#  ifdef _MSC_VER
+#    define access(path,mode)   _access(path,mode)
+#    define chmod(path,mode)    _chmod(path,mode)
+#    define strdup(str)         _strdup(str)
+#  endif
+#else
+#  include <utime.h>
+#endif
+
+
+/* values used in typeflag field */
+
+#define REGTYPE  '0'            /* regular file */
+#define AREGTYPE '\0'           /* regular file */
+#define LNKTYPE  '1'            /* link */
+#define SYMTYPE  '2'            /* reserved */
+#define CHRTYPE  '3'            /* character special */
+#define BLKTYPE  '4'            /* block special */
+#define DIRTYPE  '5'            /* directory */
+#define FIFOTYPE '6'            /* FIFO special */
+#define CONTTYPE '7'            /* reserved */
+
+/* GNU tar extensions */
+
+#define GNUTYPE_DUMPDIR  'D'    /* file names from dumped directory */
+#define GNUTYPE_LONGLINK 'K'    /* long link name */
+#define GNUTYPE_LONGNAME 'L'    /* long file name */
+#define GNUTYPE_MULTIVOL 'M'    /* continuation of file from another volume */
+#define GNUTYPE_NAMES    'N'    /* file name that does not fit into main hdr */
+#define GNUTYPE_SPARSE   'S'    /* sparse file */
+#define GNUTYPE_VOLHDR   'V'    /* tape/volume header */
+
+
+/* tar header */
+
+#define BLOCKSIZE     512
+#define SHORTNAMESIZE 100
+
+struct tar_header
+{                               /* byte offset */
+  char name[100];               /*   0 */
+  char mode[8];                 /* 100 */
+  char uid[8];                  /* 108 */
+  char gid[8];                  /* 116 */
+  char size[12];                /* 124 */
+  char mtime[12];               /* 136 */
+  char chksum[8];               /* 148 */
+  char typeflag;                /* 156 */
+  char linkname[100];           /* 157 */
+  char magic[6];                /* 257 */
+  char version[2];              /* 263 */
+  char uname[32];               /* 265 */
+  char gname[32];               /* 297 */
+  char devmajor[8];             /* 329 */
+  char devminor[8];             /* 337 */
+  char prefix[155];             /* 345 */
+                                /* 500 */
+};
+
+union tar_buffer
+{
+  char               buffer[BLOCKSIZE];
+  struct tar_header  header;
+};
+
+struct attr_item
+{
+  struct attr_item  *next;
+  char              *fname;
+  int                mode;
+  time_t             time;
+};
+
+enum { TGZ_EXTRACT, TGZ_LIST, TGZ_INVALID };
+
+char *TGZfname          OF((const char *));
+void TGZnotfound        OF((const char *));
+
+int getoct              OF((char *, int));
+char *strtime           OF((time_t *));
+int setfiletime         OF((char *, time_t));
+void push_attr          OF((struct attr_item **, char *, int, time_t));
+void restore_attr       OF((struct attr_item **));
+
+int ExprMatch           OF((char *, char *));
+
+int makedir             OF((char *));
+int matchname           OF((int, int, char **, char *));
+
+void error              OF((const char *));
+int tar                 OF((gzFile, int, int, int, char **));
+
+void help               OF((int));
+int main                OF((int, char **));
+
+char *prog;
+
+const char *TGZsuffix[] = { "\0", ".tar", ".tar.gz", ".taz", ".tgz", NULL };
+
+/* return the file name of the TGZ archive */
+/* or NULL if it does not exist */
+
+char *TGZfname (const char *arcname)
+{
+  static char buffer[1024];
+  int origlen,i;
+
+  strcpy(buffer,arcname);
+  origlen = strlen(buffer);
+
+  for (i=0; TGZsuffix[i]; i++)
+    {
+       strcpy(buffer+origlen,TGZsuffix[i]);
+       if (access(buffer,F_OK) == 0)
+         return buffer;
+    }
+  return NULL;
+}
+
+
+/* error message for the filename */
+
+void TGZnotfound (const char *arcname)
+{
+  int i;
+
+  fprintf(stderr,"%s: Couldn't find ",prog);
+  for (i=0;TGZsuffix[i];i++)
+    fprintf(stderr,(TGZsuffix[i+1]) ? "%s%s, " : "or %s%s\n",
+            arcname,
+            TGZsuffix[i]);
+  exit(1);
+}
+
+
+/* convert octal digits to int */
+/* on error return -1 */
+
+int getoct (char *p,int width)
+{
+  int result = 0;
+  char c;
+
+  while (width--)
+    {
+      c = *p++;
+      if (c == 0)
+        break;
+      if (c == ' ')
+        continue;
+      if (c < '0' || c > '7')
+        return -1;
+      result = result * 8 + (c - '0');
+    }
+  return result;
+}
+
+
+/* convert time_t to string */
+/* use the "YYYY/MM/DD hh:mm:ss" format */
+
+char *strtime (time_t *t)
+{
+  struct tm   *local;
+  static char result[32];
+
+  local = localtime(t);
+  sprintf(result,"%4d/%02d/%02d %02d:%02d:%02d",
+          local->tm_year+1900, local->tm_mon+1, local->tm_mday,
+          local->tm_hour, local->tm_min, local->tm_sec);
+  return result;
+}
+
+
+/* set file time */
+
+int setfiletime (char *fname,time_t ftime)
+{
+#ifdef WIN32
+  static int isWinNT = -1;
+  SYSTEMTIME st;
+  FILETIME locft, modft;
+  struct tm *loctm;
+  HANDLE hFile;
+  int result;
+
+  loctm = localtime(&ftime);
+  if (loctm == NULL)
+    return -1;
+
+  st.wYear         = (WORD)loctm->tm_year + 1900;
+  st.wMonth        = (WORD)loctm->tm_mon + 1;
+  st.wDayOfWeek    = (WORD)loctm->tm_wday;
+  st.wDay          = (WORD)loctm->tm_mday;
+  st.wHour         = (WORD)loctm->tm_hour;
+  st.wMinute       = (WORD)loctm->tm_min;
+  st.wSecond       = (WORD)loctm->tm_sec;
+  st.wMilliseconds = 0;
+  if (!SystemTimeToFileTime(&st, &locft) ||
+      !LocalFileTimeToFileTime(&locft, &modft))
+    return -1;
+
+  if (isWinNT < 0)
+    isWinNT = (GetVersion() < 0x80000000) ? 1 : 0;
+  hFile = CreateFile(fname, GENERIC_WRITE, 0, NULL, OPEN_EXISTING,
+                     (isWinNT ? FILE_FLAG_BACKUP_SEMANTICS : 0),
+                     NULL);
+  if (hFile == INVALID_HANDLE_VALUE)
+    return -1;
+  result = SetFileTime(hFile, NULL, NULL, &modft) ? 0 : -1;
+  CloseHandle(hFile);
+  return result;
+#else
+  struct utimbuf settime;
+
+  settime.actime = settime.modtime = ftime;
+  return utime(fname,&settime);
+#endif
+}
+
+
+/* push file attributes */
+
+void push_attr(struct attr_item **list,char *fname,int mode,time_t time)
+{
+  struct attr_item *item;
+
+  item = (struct attr_item *)malloc(sizeof(struct attr_item));
+  if (item == NULL)
+    error("Out of memory");
+  item->fname = strdup(fname);
+  item->mode  = mode;
+  item->time  = time;
+  item->next  = *list;
+  *list       = item;
+}
+
+
+/* restore file attributes */
+
+void restore_attr(struct attr_item **list)
+{
+  struct attr_item *item, *prev;
+
+  for (item = *list; item != NULL; )
+    {
+      setfiletime(item->fname,item->time);
+      chmod(item->fname,item->mode);
+      prev = item;
+      item = item->next;
+      free(prev);
+    }
+  *list = NULL;
+}
+
+
+/* match regular expression */
+
+#define ISSPECIAL(c) (((c) == '*') || ((c) == '/'))
+
+int ExprMatch (char *string,char *expr)
+{
+  while (1)
+    {
+      if (ISSPECIAL(*expr))
+        {
+          if (*expr == '/')
+            {
+              if (*string != '\\' && *string != '/')
+                return 0;
+              string ++; expr++;
+            }
+          else if (*expr == '*')
+            {
+              if (*expr ++ == 0)
+                return 1;
+              while (*++string != *expr)
+                if (*string == 0)
+                  return 0;
+            }
+        }
+      else
+        {
+          if (*string != *expr)
+            return 0;
+          if (*expr++ == 0)
+            return 1;
+          string++;
+        }
+    }
+}
+
+
+/* recursive mkdir */
+/* abort on ENOENT; ignore other errors like "directory already exists" */
+/* return 1 if OK */
+/*        0 on error */
+
+int makedir (char *newdir)
+{
+  char *buffer = strdup(newdir);
+  char *p;
+  int  len = strlen(buffer);
+
+  if (len <= 0) {
+    free(buffer);
+    return 0;
+  }
+  if (buffer[len-1] == '/') {
+    buffer[len-1] = '\0';
+  }
+  if (mkdir(buffer, 0755) == 0)
+    {
+      free(buffer);
+      return 1;
+    }
+
+  p = buffer+1;
+  while (1)
+    {
+      char hold;
+
+      while(*p && *p != '\\' && *p != '/')
+        p++;
+      hold = *p;
+      *p = 0;
+      if ((mkdir(buffer, 0755) == -1) && (errno == ENOENT))
+        {
+          fprintf(stderr,"%s: Couldn't create directory %s\n",prog,buffer);
+          free(buffer);
+          return 0;
+        }
+      if (hold == 0)
+        break;
+      *p++ = hold;
+    }
+  free(buffer);
+  return 1;
+}
+
+
+int matchname (int arg,int argc,char **argv,char *fname)
+{
+  if (arg == argc)      /* no arguments given (untgz tgzarchive) */
+    return 1;
+
+  while (arg < argc)
+    if (ExprMatch(fname,argv[arg++]))
+      return 1;
+
+  return 0; /* ignore this for the moment being */
+}
+
+
+/* tar file list or extract */
+
+int tar (gzFile in,int action,int arg,int argc,char **argv)
+{
+  union  tar_buffer buffer;
+  int    len;
+  int    err;
+  int    getheader = 1;
+  int    remaining = 0;
+  FILE   *outfile = NULL;
+  char   fname[BLOCKSIZE];
+  int    tarmode;
+  time_t tartime;
+  struct attr_item *attributes = NULL;
+
+  if (action == TGZ_LIST)
+    printf("    date      time     size                       file\n"
+           " ---------- -------- --------- -------------------------------------\n");
+  while (1)
+    {
+      len = gzread(in, &buffer, BLOCKSIZE);
+      if (len < 0)
+        error(gzerror(in, &err));
+      /*
+       * Always expect complete blocks to process
+       * the tar information.
+       */
+      if (len != BLOCKSIZE)
+        {
+          action = TGZ_INVALID; /* force error exit */
+          remaining = 0;        /* force I/O cleanup */
+        }
+
+      /*
+       * If we have to get a tar header
+       */
+      if (getheader >= 1)
+        {
+          /*
+           * if we met the end of the tar
+           * or the end-of-tar block,
+           * we are done
+           */
+          if (len == 0 || buffer.header.name[0] == 0)
+            break;
+
+          tarmode = getoct(buffer.header.mode,8);
+          tartime = (time_t)getoct(buffer.header.mtime,12);
+          if (tarmode == -1 || tartime == (time_t)-1)
+            {
+              buffer.header.name[0] = 0;
+              action = TGZ_INVALID;
+            }
+
+          if (getheader == 1)
+            {
+              strncpy(fname,buffer.header.name,SHORTNAMESIZE);
+              if (fname[SHORTNAMESIZE-1] != 0)
+                  fname[SHORTNAMESIZE] = 0;
+            }
+          else
+            {
+              /*
+               * The file name is longer than SHORTNAMESIZE
+               */
+              if (strncmp(fname,buffer.header.name,SHORTNAMESIZE-1) != 0)
+                  error("bad long name");
+              getheader = 1;
+            }
+
+          /*
+           * Act according to the type flag
+           */
+          switch (buffer.header.typeflag)
+            {
+            case DIRTYPE:
+              if (action == TGZ_LIST)
+                printf(" %s     <dir> %s\n",strtime(&tartime),fname);
+              if (action == TGZ_EXTRACT)
+                {
+                  makedir(fname);
+                  push_attr(&attributes,fname,tarmode,tartime);
+                }
+              break;
+            case REGTYPE:
+            case AREGTYPE:
+              remaining = getoct(buffer.header.size,12);
+              if (remaining == -1)
+                {
+                  action = TGZ_INVALID;
+                  break;
+                }
+              if (action == TGZ_LIST)
+                printf(" %s %9d %s\n",strtime(&tartime),remaining,fname);
+              else if (action == TGZ_EXTRACT)
+                {
+                  if (matchname(arg,argc,argv,fname))
+                    {
+                      outfile = fopen(fname,"wb");
+                      if (outfile == NULL) {
+                        /* try creating directory */
+                        char *p = strrchr(fname, '/');
+                        if (p != NULL) {
+                          *p = '\0';
+                          makedir(fname);
+                          *p = '/';
+                          outfile = fopen(fname,"wb");
+                        }
+                      }
+                      if (outfile != NULL)
+                        printf("Extracting %s\n",fname);
+                      else
+                        fprintf(stderr, "%s: Couldn't create %s",prog,fname);
+                    }
+                  else
+                    outfile = NULL;
+                }
+              getheader = 0;
+              break;
+            case GNUTYPE_LONGLINK:
+            case GNUTYPE_LONGNAME:
+              remaining = getoct(buffer.header.size,12);
+              if (remaining < 0 || remaining >= BLOCKSIZE)
+                {
+                  action = TGZ_INVALID;
+                  break;
+                }
+              len = gzread(in, fname, BLOCKSIZE);
+              if (len < 0)
+                error(gzerror(in, &err));
+              if (fname[BLOCKSIZE-1] != 0 || (int)strlen(fname) > remaining)
+                {
+                  action = TGZ_INVALID;
+                  break;
+                }
+              getheader = 2;
+              break;
+            default:
+              if (action == TGZ_LIST)
+                printf(" %s     <---> %s\n",strtime(&tartime),fname);
+              break;
+            }
+        }
+      else
+        {
+          unsigned int bytes = (remaining > BLOCKSIZE) ? BLOCKSIZE : remaining;
+
+          if (outfile != NULL)
+            {
+              if (fwrite(&buffer,sizeof(char),bytes,outfile) != bytes)
+                {
+                  fprintf(stderr,
+                    "%s: Error writing %s -- skipping\n",prog,fname);
+                  fclose(outfile);
+                  outfile = NULL;
+                  remove(fname);
+                }
+            }
+          remaining -= bytes;
+        }
+
+      if (remaining == 0)
+        {
+          getheader = 1;
+          if (outfile != NULL)
+            {
+              fclose(outfile);
+              outfile = NULL;
+              if (action != TGZ_INVALID)
+                push_attr(&attributes,fname,tarmode,tartime);
+            }
+        }
+
+      /*
+       * Abandon if errors are found
+       */
+      if (action == TGZ_INVALID)
+        {
+          error("broken archive");
+          break;
+        }
+    }
+
+  /*
+   * Restore file modes and time stamps
+   */
+  restore_attr(&attributes);
+
+  if (gzclose(in) != Z_OK)
+    error("failed gzclose");
+
+  return 0;
+}
+
+
+/* ============================================================ */
+
+void help(int exitval)
+{
+  printf("untgz version 0.2.1\n"
+         "  using zlib version %s\n\n",
+         zlibVersion());
+  printf("Usage: untgz file.tgz            extract all files\n"
+         "       untgz file.tgz fname ...  extract selected files\n"
+         "       untgz -l file.tgz         list archive contents\n"
+         "       untgz -h                  display this help\n");
+  exit(exitval);
+}
+
+void error(const char *msg)
+{
+  fprintf(stderr, "%s: %s\n", prog, msg);
+  exit(1);
+}
+
+
+/* ============================================================ */
+
+#if defined(WIN32) && defined(__GNUC__)
+int _CRT_glob = 0;      /* disable argument globbing in MinGW */
+#endif
+
+int main(int argc,char **argv)
+{
+    int         action = TGZ_EXTRACT;
+    int         arg = 1;
+    char        *TGZfile;
+    gzFile      *f;
+
+    prog = strrchr(argv[0],'\\');
+    if (prog == NULL)
+      {
+        prog = strrchr(argv[0],'/');
+        if (prog == NULL)
+          {
+            prog = strrchr(argv[0],':');
+            if (prog == NULL)
+              prog = argv[0];
+            else
+              prog++;
+          }
+        else
+          prog++;
+      }
+    else
+      prog++;
+
+    if (argc == 1)
+      help(0);
+
+    if (strcmp(argv[arg],"-l") == 0)
+      {
+        action = TGZ_LIST;
+        if (argc == ++arg)
+          help(0);
+      }
+    else if (strcmp(argv[arg],"-h") == 0)
+      {
+        help(0);
+      }
+
+    if ((TGZfile = TGZfname(argv[arg])) == NULL)
+      TGZnotfound(argv[arg]);
+
+    ++arg;
+    if ((action == TGZ_LIST) && (arg != argc))
+      help(1);
+
+/*
+ *  Process the TGZ file
+ */
+    switch(action)
+      {
+      case TGZ_LIST:
+      case TGZ_EXTRACT:
+        f = gzopen(TGZfile,"rb");
+        if (f == NULL)
+          {
+            fprintf(stderr,"%s: Couldn't gzopen %s\n",prog,TGZfile);
+            return 1;
+          }
+        exit(tar(f, action, arg, argc, argv));
+      break;
+
+      default:
+        error("Unknown option");
+        exit(1);
+      }
+
+    return 0;
+}
diff --git a/gs/zlib/contrib/vstudio/readme.txt b/gs/zlib/contrib/vstudio/readme.txt
new file mode 100644
index 000000000..16159f9cd
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/readme.txt
@@ -0,0 +1,73 @@
+Building instructions for the DLL versions of Zlib 1.2.3

+========================================================

+

+This directory contains projects that build zlib and minizip using

+Microsoft Visual C++ 7.0/7.1, and Visual C++ .

+

+You don't need to build these projects yourself. You can download the

+binaries from:

+  http://www.winimage.com/zLibDll

+

+More information can be found at this site.

+

+

+Build instructions for Visual Studio 7.x (32 bits)

+--------------------------------------------------

+- Uncompress current zlib, including all contrib/* files

+- Download the crtdll library from

+    http://www.winimage.com/zLibDll/crtdll.zip

+  Unzip crtdll.zip to extract crtdll.lib on contrib\vstudio\vc7.

+- Open contrib\vstudio\vc7\zlibvc.sln with Microsoft Visual C++ 7.x

+  (Visual Studio .Net 2002 or 2003).

+

+Build instructions for Visual Studio 2005 (32 bits or 64 bits)

+--------------------------------------------------------------

+- Uncompress current zlib, including all contrib/* files

+- For 32 bits only: download the crtdll library from

+    http://www.winimage.com/zLibDll/crtdll.zip

+  Unzip crtdll.zip to extract crtdll.lib on contrib\vstudio\vc8.

+- Open contrib\vstudio\vc8\zlibvc.sln with Microsoft Visual C++ 8.0

+

+Build instructions for Visual Studio 2005 64 bits, PSDK compiler

+----------------------------------------------------------------

+at the time of writing this text file, Visual Studio 2005 (and 

+  Microsoft Visual C++ 8.0) is on the beta 2 stage.

+Using you can get the free 64 bits compiler from Platform SDK, 

+  which is NOT a beta, and compile using the Visual studio 2005 IDE

+see http://www.winimage.com/misc/sdk64onvs2005/ for instruction

+

+- Uncompress current zlib, including all contrib/* files

+- start Visual Studio 2005 from a platform SDK command prompt, using

+  the /useenv switch

+- Open contrib\vstudio\vc8\zlibvc.sln with Microsoft Visual C++ 8.0

+

+

+Important

+---------

+- To use zlibwapi.dll in your application, you must define the

+  macro ZLIB_WINAPI when compiling your application's source files.

+

+

+Additional notes

+----------------

+- This DLL, named zlibwapi.dll, is compatible to the old zlib.dll built

+  by Gilles Vollant from the zlib 1.1.x sources, and distributed at

+    http://www.winimage.com/zLibDll

+  It uses the WINAPI calling convention for the exported functions, and

+  includes the minizip functionality. If your application needs that

+  particular build of zlib.dll, you can rename zlibwapi.dll to zlib.dll.

+

+- The new DLL was renamed because there exist several incompatible

+  versions of zlib.dll on the Internet.

+

+- There is also an official DLL build of zlib, named zlib1.dll. This one

+  is exporting the functions using the CDECL convention. See the file

+  win32\DLL_FAQ.txt found in this zlib distribution.

+

+- There used to be a ZLIB_DLL macro in zlib 1.1.x, but now this symbol

+  has a slightly different effect. To avoid compatibility problems, do

+  not define it here.

+

+

+Gilles Vollant

+info@winimage.com

diff --git a/gs/zlib/contrib/vstudio/vc7/miniunz.vcproj b/gs/zlib/contrib/vstudio/vc7/miniunz.vcproj
new file mode 100644
index 000000000..ad5117c84
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc7/miniunz.vcproj
@@ -0,0 +1,126 @@
+<?xml version="1.0" encoding = "Windows-1252"?>

+<VisualStudioProject

+	ProjectType="Visual C++"

+	Version="7.00"

+	Name="miniunz"

+	ProjectGUID="{C52F9E7B-498A-42BE-8DB4-85A15694382A}"

+	Keyword="Win32Proj">

+	<Platforms>

+		<Platform

+			Name="Win32"/>

+	</Platforms>

+	<Configurations>

+		<Configuration

+			Name="Debug|Win32"

+			OutputDirectory="Debug"

+			IntermediateDirectory="Debug"

+			ConfigurationType="1"

+			CharacterSet="2">

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;_DEBUG;_CONSOLE"

+				MinimalRebuild="TRUE"

+				BasicRuntimeChecks="3"

+				RuntimeLibrary="5"

+				UsePrecompiledHeader="0"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="TRUE"

+				DebugInformationFormat="4"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)/miniunz.exe"

+				LinkIncremental="2"

+				GenerateDebugInformation="TRUE"

+				ProgramDatabaseFile="$(OutDir)/miniunz.pdb"

+				SubSystem="1"

+				TargetMachine="1"/>

+			<Tool

+				Name="VCMIDLTool"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+			<Tool

+				Name="VCWebDeploymentTool"/>

+		</Configuration>

+		<Configuration

+			Name="Release|Win32"

+			OutputDirectory="Release"

+			IntermediateDirectory="Release"

+			ConfigurationType="1"

+			CharacterSet="2">

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="TRUE"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;NDEBUG;_CONSOLE"

+				StringPooling="TRUE"

+				RuntimeLibrary="4"

+				EnableFunctionLevelLinking="TRUE"

+				UsePrecompiledHeader="0"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="TRUE"

+				DebugInformationFormat="3"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)/miniunz.exe"

+				LinkIncremental="1"

+				GenerateDebugInformation="TRUE"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="1"/>

+			<Tool

+				Name="VCMIDLTool"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+			<Tool

+				Name="VCWebDeploymentTool"/>

+		</Configuration>

+	</Configurations>

+	<Files>

+		<Filter

+			Name="Source Files"

+			Filter="cpp;c;cxx;def;odl;idl;hpj;bat;asm">

+			<File

+				RelativePath="..\..\minizip\miniunz.c">

+			</File>

+		</Filter>

+		<Filter

+			Name="Header Files"

+			Filter="h;hpp;hxx;hm;inl;inc">

+		</Filter>

+		<Filter

+			Name="Resource Files"

+			Filter="rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe">

+		</Filter>

+		<File

+			RelativePath="ReleaseDll\zlibwapi.lib">

+		</File>

+	</Files>

+	<Globals>

+	</Globals>

+</VisualStudioProject>

diff --git a/gs/zlib/contrib/vstudio/vc7/minizip.vcproj b/gs/zlib/contrib/vstudio/vc7/minizip.vcproj
new file mode 100644
index 000000000..fb5b6320d
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc7/minizip.vcproj
@@ -0,0 +1,126 @@
+<?xml version="1.0" encoding = "Windows-1252"?>

+<VisualStudioProject

+	ProjectType="Visual C++"

+	Version="7.00"

+	Name="minizip"

+	ProjectGUID="{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}"

+	Keyword="Win32Proj">

+	<Platforms>

+		<Platform

+			Name="Win32"/>

+	</Platforms>

+	<Configurations>

+		<Configuration

+			Name="Debug|Win32"

+			OutputDirectory="Debug"

+			IntermediateDirectory="Debug"

+			ConfigurationType="1"

+			CharacterSet="2">

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;_DEBUG;_CONSOLE"

+				MinimalRebuild="TRUE"

+				BasicRuntimeChecks="3"

+				RuntimeLibrary="5"

+				UsePrecompiledHeader="0"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="TRUE"

+				DebugInformationFormat="4"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)/minizip.exe"

+				LinkIncremental="2"

+				GenerateDebugInformation="TRUE"

+				ProgramDatabaseFile="$(OutDir)/minizip.pdb"

+				SubSystem="1"

+				TargetMachine="1"/>

+			<Tool

+				Name="VCMIDLTool"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+			<Tool

+				Name="VCWebDeploymentTool"/>

+		</Configuration>

+		<Configuration

+			Name="Release|Win32"

+			OutputDirectory="Release"

+			IntermediateDirectory="Release"

+			ConfigurationType="1"

+			CharacterSet="2">

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="TRUE"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;NDEBUG;_CONSOLE"

+				StringPooling="TRUE"

+				RuntimeLibrary="4"

+				EnableFunctionLevelLinking="TRUE"

+				UsePrecompiledHeader="0"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="TRUE"

+				DebugInformationFormat="3"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)/minizip.exe"

+				LinkIncremental="1"

+				GenerateDebugInformation="TRUE"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="1"/>

+			<Tool

+				Name="VCMIDLTool"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+			<Tool

+				Name="VCWebDeploymentTool"/>

+		</Configuration>

+	</Configurations>

+	<Files>

+		<Filter

+			Name="Source Files"

+			Filter="cpp;c;cxx;def;odl;idl;hpj;bat;asm">

+			<File

+				RelativePath="..\..\minizip\minizip.c">

+			</File>

+		</Filter>

+		<Filter

+			Name="Header Files"

+			Filter="h;hpp;hxx;hm;inl;inc">

+		</Filter>

+		<Filter

+			Name="Resource Files"

+			Filter="rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe">

+		</Filter>

+		<File

+			RelativePath="ReleaseDll\zlibwapi.lib">

+		</File>

+	</Files>

+	<Globals>

+	</Globals>

+</VisualStudioProject>

diff --git a/gs/zlib/contrib/vstudio/vc7/testzlib.vcproj b/gs/zlib/contrib/vstudio/vc7/testzlib.vcproj
new file mode 100644
index 000000000..97bc3e8c8
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc7/testzlib.vcproj
@@ -0,0 +1,126 @@
+<?xml version="1.0" encoding = "Windows-1252"?>

+<VisualStudioProject

+	ProjectType="Visual C++"

+	Version="7.00"

+	Name="testZlibDll"

+	ProjectGUID="{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}"

+	Keyword="Win32Proj">

+	<Platforms>

+		<Platform

+			Name="Win32"/>

+	</Platforms>

+	<Configurations>

+		<Configuration

+			Name="Debug|Win32"

+			OutputDirectory="Debug"

+			IntermediateDirectory="Debug"

+			ConfigurationType="1"

+			CharacterSet="2">

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\.."

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;_DEBUG;_CONSOLE"

+				MinimalRebuild="TRUE"

+				BasicRuntimeChecks="3"

+				RuntimeLibrary="5"

+				UsePrecompiledHeader="0"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="TRUE"

+				DebugInformationFormat="4"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="2"

+				GenerateDebugInformation="TRUE"

+				ProgramDatabaseFile="$(OutDir)/testzlib.pdb"

+				SubSystem="1"

+				TargetMachine="1"/>

+			<Tool

+				Name="VCMIDLTool"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+			<Tool

+				Name="VCWebDeploymentTool"/>

+		</Configuration>

+		<Configuration

+			Name="Release|Win32"

+			OutputDirectory="Release"

+			IntermediateDirectory="Release"

+			ConfigurationType="1"

+			CharacterSet="2">

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="TRUE"

+				AdditionalIncludeDirectories="..\..\.."

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;NDEBUG;_CONSOLE"

+				StringPooling="TRUE"

+				RuntimeLibrary="4"

+				EnableFunctionLevelLinking="TRUE"

+				UsePrecompiledHeader="0"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="TRUE"

+				DebugInformationFormat="3"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="1"

+				GenerateDebugInformation="TRUE"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="1"/>

+			<Tool

+				Name="VCMIDLTool"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+			<Tool

+				Name="VCWebDeploymentTool"/>

+		</Configuration>

+	</Configurations>

+	<Files>

+		<Filter

+			Name="Source Files"

+			Filter="cpp;c;cxx;def;odl;idl;hpj;bat;asm">

+			<File

+				RelativePath="..\..\testzlib\testzlib.c">

+			</File>

+		</Filter>

+		<Filter

+			Name="Header Files"

+			Filter="h;hpp;hxx;hm;inl;inc">

+		</Filter>

+		<Filter

+			Name="Resource Files"

+			Filter="rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe">

+		</Filter>

+		<File

+			RelativePath="ReleaseDll\zlibwapi.lib">

+		</File>

+	</Files>

+	<Globals>

+	</Globals>

+</VisualStudioProject>

diff --git a/gs/zlib/contrib/vstudio/vc7/zlib.rc b/gs/zlib/contrib/vstudio/vc7/zlib.rc
new file mode 100644
index 000000000..72cb8b4c3
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc7/zlib.rc
@@ -0,0 +1,32 @@
+#include <windows.h>

+

+#define IDR_VERSION1  1

+IDR_VERSION1	VERSIONINFO	MOVEABLE IMPURE LOADONCALL DISCARDABLE

+  FILEVERSION	 1,2,3,0

+  PRODUCTVERSION 1,2,3,0

+  FILEFLAGSMASK	VS_FFI_FILEFLAGSMASK

+  FILEFLAGS	0

+  FILEOS	VOS_DOS_WINDOWS32

+  FILETYPE	VFT_DLL

+  FILESUBTYPE	0	// not used

+BEGIN

+  BLOCK "StringFileInfo"

+  BEGIN

+    BLOCK "040904E4"

+    //language ID = U.S. English, char set = Windows, Multilingual

+

+    BEGIN

+      VALUE "FileDescription", "zlib data compression library\0"

+      VALUE "FileVersion",	"1.2.3.0\0"

+      VALUE "InternalName",	"zlib\0"

+      VALUE "OriginalFilename",	"zlib.dll\0"

+      VALUE "ProductName",	"ZLib.DLL\0"

+      VALUE "Comments","DLL support by Alessandro Iacopetti & Gilles Vollant\0"

+      VALUE "LegalCopyright", "(C) 1995-2003 Jean-loup Gailly & Mark Adler\0"

+    END

+  END

+  BLOCK "VarFileInfo"

+  BEGIN

+    VALUE "Translation", 0x0409, 1252

+  END

+END

diff --git a/gs/zlib/contrib/vstudio/vc7/zlibstat.vcproj b/gs/zlib/contrib/vstudio/vc7/zlibstat.vcproj
new file mode 100644
index 000000000..766d7a4d6
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc7/zlibstat.vcproj
@@ -0,0 +1,246 @@
+<?xml version="1.0" encoding = "Windows-1252"?>

+<VisualStudioProject

+	ProjectType="Visual C++"

+	Version="7.00"

+	Name="zlibstat"

+	SccProjectName=""

+	SccLocalPath="">

+	<Platforms>

+		<Platform

+			Name="Win32"/>

+	</Platforms>

+	<Configurations>

+		<Configuration

+			Name="Debug|Win32"

+			OutputDirectory=".\zlibstatDebug"

+			IntermediateDirectory=".\zlibstatDebug"

+			ConfigurationType="4"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="FALSE">

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI"

+				ExceptionHandling="FALSE"

+				RuntimeLibrary="5"

+				PrecompiledHeaderFile=".\zlibstatDebug/zlibstat.pch"

+				AssemblerListingLocation=".\zlibstatDebug/"

+				ObjectFile=".\zlibstatDebug/"

+				ProgramDataBaseFileName=".\zlibstatDebug/"

+				WarningLevel="3"

+				SuppressStartupBanner="TRUE"

+				DebugInformationFormat="1"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="/NODEFAULTLIB "

+				OutputFile=".\zlibstatDebug\zlibstat.lib"

+				SuppressStartupBanner="TRUE"/>

+			<Tool

+				Name="VCMIDLTool"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseAxp|Win32"

+			OutputDirectory=".\zlibsta0"

+			IntermediateDirectory=".\zlibsta0"

+			ConfigurationType="4"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="FALSE">

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI"

+				StringPooling="TRUE"

+				ExceptionHandling="FALSE"

+				RuntimeLibrary="4"

+				EnableFunctionLevelLinking="TRUE"

+				PrecompiledHeaderFile=".\zlibsta0/zlibstat.pch"

+				AssemblerListingLocation=".\zlibsta0/"

+				ObjectFile=".\zlibsta0/"

+				ProgramDataBaseFileName=".\zlibsta0/"

+				WarningLevel="3"

+				SuppressStartupBanner="TRUE"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="/NODEFAULTLIB "

+				OutputFile=".\zlibsta0\zlibstat.lib"

+				SuppressStartupBanner="TRUE"/>

+			<Tool

+				Name="VCMIDLTool"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+		</Configuration>

+		<Configuration

+			Name="Release|Win32"

+			OutputDirectory=".\zlibstat"

+			IntermediateDirectory=".\zlibstat"

+			ConfigurationType="4"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="FALSE">

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;ASMV;ASMINF"

+				StringPooling="TRUE"

+				ExceptionHandling="FALSE"

+				RuntimeLibrary="4"

+				EnableFunctionLevelLinking="TRUE"

+				PrecompiledHeaderFile=".\zlibstat/zlibstat.pch"

+				AssemblerListingLocation=".\zlibstat/"

+				ObjectFile=".\zlibstat/"

+				ProgramDataBaseFileName=".\zlibstat/"

+				WarningLevel="3"

+				SuppressStartupBanner="TRUE"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="..\..\masmx86\gvmat32.obj ..\..\masmx86\inffas32.obj /NODEFAULTLIB "

+				OutputFile=".\zlibstat\zlibstat.lib"

+				SuppressStartupBanner="TRUE"/>

+			<Tool

+				Name="VCMIDLTool"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutAsm|Win32"

+			OutputDirectory="zlibstatWithoutAsm"

+			IntermediateDirectory="zlibstatWithoutAsm"

+			ConfigurationType="4"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="FALSE">

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI"

+				StringPooling="TRUE"

+				ExceptionHandling="FALSE"

+				RuntimeLibrary="4"

+				EnableFunctionLevelLinking="TRUE"

+				PrecompiledHeaderFile=".\zlibstat/zlibstat.pch"

+				AssemblerListingLocation=".\zlibstatWithoutAsm/"

+				ObjectFile=".\zlibstatWithoutAsm/"

+				ProgramDataBaseFileName=".\zlibstatWithoutAsm/"

+				WarningLevel="3"

+				SuppressStartupBanner="TRUE"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions=" /NODEFAULTLIB "

+				OutputFile=".\zlibstatWithoutAsm\zlibstat.lib"

+				SuppressStartupBanner="TRUE"/>

+			<Tool

+				Name="VCMIDLTool"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+		</Configuration>

+	</Configurations>

+	<Files>

+		<Filter

+			Name="Source Files"

+			Filter="">

+			<File

+				RelativePath="..\..\..\adler32.c">

+			</File>

+			<File

+				RelativePath="..\..\..\compress.c">

+			</File>

+			<File

+				RelativePath="..\..\..\crc32.c">

+			</File>

+			<File

+				RelativePath="..\..\..\deflate.c">

+			</File>

+			<File

+				RelativePath="..\..\masmx86\gvmat32c.c">

+			</File>

+			<File

+				RelativePath="..\..\..\gzio.c">

+			</File>

+			<File

+				RelativePath="..\..\..\infback.c">

+			</File>

+			<File

+				RelativePath="..\..\..\inffast.c">

+			</File>

+			<File

+				RelativePath="..\..\..\inflate.c">

+			</File>

+			<File

+				RelativePath="..\..\..\inftrees.c">

+			</File>

+			<File

+				RelativePath="..\..\minizip\ioapi.c">

+			</File>

+			<File

+				RelativePath="..\..\..\trees.c">

+			</File>

+			<File

+				RelativePath="..\..\..\uncompr.c">

+			</File>

+			<File

+				RelativePath="..\..\minizip\unzip.c">

+			</File>

+			<File

+				RelativePath="..\..\minizip\zip.c">

+			</File>

+			<File

+				RelativePath=".\zlib.rc">

+			</File>

+			<File

+				RelativePath=".\zlibvc.def">

+			</File>

+			<File

+				RelativePath="..\..\..\zutil.c">

+			</File>

+		</Filter>

+	</Files>

+	<Globals>

+	</Globals>

+</VisualStudioProject>

diff --git a/gs/zlib/contrib/vstudio/vc7/zlibvc.def b/gs/zlib/contrib/vstudio/vc7/zlibvc.def
new file mode 100644
index 000000000..a40e71541
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc7/zlibvc.def
@@ -0,0 +1,92 @@
+

+VERSION		1.23

+

+HEAPSIZE	1048576,8192

+

+EXPORTS

+        adler32                                  @1

+        compress                                 @2

+        crc32                                    @3

+        deflate                                  @4

+        deflateCopy                              @5

+        deflateEnd                               @6

+        deflateInit2_                            @7

+        deflateInit_                             @8

+        deflateParams                            @9

+        deflateReset                             @10

+        deflateSetDictionary                     @11

+        gzclose                                  @12

+        gzdopen                                  @13

+        gzerror                                  @14

+        gzflush                                  @15

+        gzopen                                   @16

+        gzread                                   @17

+        gzwrite                                  @18

+        inflate                                  @19

+        inflateEnd                               @20

+        inflateInit2_                            @21

+        inflateInit_                             @22

+        inflateReset                             @23

+        inflateSetDictionary                     @24

+        inflateSync                              @25

+        uncompress                               @26

+        zlibVersion                              @27

+        gzprintf                                 @28

+        gzputc                                   @29

+        gzgetc                                   @30

+        gzseek                                   @31

+        gzrewind                                 @32

+        gztell                                   @33

+        gzeof                                    @34

+        gzsetparams                              @35

+        zError                                   @36

+        inflateSyncPoint                         @37

+        get_crc_table                            @38

+        compress2                                @39

+        gzputs                                   @40

+        gzgets                                   @41

+        inflateCopy                              @42

+        inflateBackInit_                         @43

+        inflateBack                              @44

+        inflateBackEnd                           @45

+        compressBound                            @46

+        deflateBound                             @47

+        gzclearerr                               @48

+        gzungetc                                 @49

+        zlibCompileFlags                         @50

+        deflatePrime                             @51

+

+        unzOpen                                  @61

+        unzClose                                 @62

+        unzGetGlobalInfo                         @63

+        unzGetCurrentFileInfo                    @64

+        unzGoToFirstFile                         @65

+        unzGoToNextFile                          @66

+        unzOpenCurrentFile                       @67

+        unzReadCurrentFile                       @68

+        unzOpenCurrentFile3                      @69

+        unztell                                  @70

+        unzeof                                   @71

+        unzCloseCurrentFile                      @72

+        unzGetGlobalComment                      @73

+        unzStringFileNameCompare                 @74

+        unzLocateFile                            @75

+        unzGetLocalExtrafield                    @76

+        unzOpen2                                 @77

+        unzOpenCurrentFile2                      @78

+        unzOpenCurrentFilePassword               @79

+

+        zipOpen                                  @80

+        zipOpenNewFileInZip                      @81

+        zipWriteInFileInZip                      @82

+        zipCloseFileInZip                        @83

+        zipClose                                 @84

+        zipOpenNewFileInZip2                     @86

+        zipCloseFileInZipRaw                     @87

+        zipOpen2                                 @88

+        zipOpenNewFileInZip3                     @89

+

+        unzGetFilePos                            @100

+        unzGoToFilePos                           @101

+

+        fill_win32_filefunc                      @110

diff --git a/gs/zlib/contrib/vstudio/vc7/zlibvc.sln b/gs/zlib/contrib/vstudio/vc7/zlibvc.sln
new file mode 100644
index 000000000..927b42b7b
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc7/zlibvc.sln
@@ -0,0 +1,78 @@
+Microsoft Visual Studio Solution File, Format Version 7.00

+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "zlibstat", "zlibstat.vcproj", "{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}"

+EndProject

+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "zlibvc", "zlibvc.vcproj", "{8FD826F8-3739-44E6-8CC8-997122E53B8D}"

+EndProject

+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "minizip", "minizip.vcproj", "{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}"

+EndProject

+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "miniunz", "miniunz.vcproj", "{C52F9E7B-498A-42BE-8DB4-85A15694382A}"

+EndProject

+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "testZlibDll", "testzlib.vcproj", "{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}"

+EndProject

+Global

+	GlobalSection(SolutionConfiguration) = preSolution

+		ConfigName.0 = Debug

+		ConfigName.1 = Release

+		ConfigName.2 = ReleaseAxp

+		ConfigName.3 = ReleaseWithoutAsm

+		ConfigName.4 = ReleaseWithoutCrtdll

+	EndGlobalSection

+	GlobalSection(ProjectDependencies) = postSolution

+	EndGlobalSection

+	GlobalSection(ProjectConfiguration) = postSolution

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.Debug.ActiveCfg = Debug|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.Debug.Build.0 = Debug|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.Release.ActiveCfg = Release|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.Release.Build.0 = Release|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseAxp.ActiveCfg = ReleaseAxp|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseAxp.Build.0 = ReleaseAxp|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseWithoutAsm.ActiveCfg = ReleaseWithoutAsm|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseWithoutAsm.Build.0 = ReleaseWithoutAsm|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseWithoutCrtdll.ActiveCfg = ReleaseAxp|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseWithoutCrtdll.Build.0 = ReleaseAxp|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Debug.ActiveCfg = Debug|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Debug.Build.0 = Debug|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Release.ActiveCfg = Release|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Release.Build.0 = Release|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.ReleaseAxp.ActiveCfg = ReleaseAxp|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.ReleaseAxp.Build.0 = ReleaseAxp|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.ReleaseWithoutAsm.ActiveCfg = ReleaseWithoutAsm|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.ReleaseWithoutAsm.Build.0 = ReleaseWithoutAsm|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.ReleaseWithoutCrtdll.ActiveCfg = ReleaseWithoutCrtdll|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.ReleaseWithoutCrtdll.Build.0 = ReleaseWithoutCrtdll|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Debug.ActiveCfg = Debug|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Debug.Build.0 = Debug|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Release.ActiveCfg = Release|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Release.Build.0 = Release|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.ReleaseAxp.ActiveCfg = Release|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.ReleaseAxp.Build.0 = Release|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm.ActiveCfg = Release|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm.Build.0 = Release|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutCrtdll.ActiveCfg = Release|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutCrtdll.Build.0 = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Debug.ActiveCfg = Debug|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Debug.Build.0 = Debug|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Release.ActiveCfg = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Release.Build.0 = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.ReleaseAxp.ActiveCfg = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.ReleaseAxp.Build.0 = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.ReleaseWithoutAsm.ActiveCfg = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.ReleaseWithoutAsm.Build.0 = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.ReleaseWithoutCrtdll.ActiveCfg = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.ReleaseWithoutCrtdll.Build.0 = Release|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}.Debug.ActiveCfg = Debug|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}.Debug.Build.0 = Debug|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}.Release.ActiveCfg = Release|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}.Release.Build.0 = Release|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}.ReleaseAxp.ActiveCfg = Release|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}.ReleaseAxp.Build.0 = Release|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}.ReleaseWithoutAsm.ActiveCfg = Release|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}.ReleaseWithoutAsm.Build.0 = Release|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}.ReleaseWithoutCrtdll.ActiveCfg = Release|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654C}.ReleaseWithoutCrtdll.Build.0 = Release|Win32

+	EndGlobalSection

+	GlobalSection(ExtensibilityGlobals) = postSolution

+	EndGlobalSection

+	GlobalSection(ExtensibilityAddIns) = postSolution

+	EndGlobalSection

+EndGlobal

diff --git a/gs/zlib/contrib/vstudio/vc7/zlibvc.vcproj b/gs/zlib/contrib/vstudio/vc7/zlibvc.vcproj
new file mode 100644
index 000000000..8533b4947
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc7/zlibvc.vcproj
@@ -0,0 +1,445 @@
+<?xml version="1.0" encoding = "Windows-1252"?>

+<VisualStudioProject

+	ProjectType="Visual C++"

+	Version="7.00"

+	Name="zlibvc"

+	SccProjectName=""

+	SccLocalPath="">

+	<Platforms>

+		<Platform

+			Name="Win32"/>

+	</Platforms>

+	<Configurations>

+		<Configuration

+			Name="Debug|Win32"

+			OutputDirectory=".\DebugDll"

+			IntermediateDirectory=".\DebugDll"

+			ConfigurationType="2"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="FALSE">

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32,ZLIB_WINAPI,ASMV,ASMINF"

+				ExceptionHandling="FALSE"

+				RuntimeLibrary="1"

+				PrecompiledHeaderFile=".\DebugDll/zlibvc.pch"

+				AssemblerListingLocation=".\DebugDll/"

+				ObjectFile=".\DebugDll/"

+				ProgramDataBaseFileName=".\DebugDll/"

+				WarningLevel="3"

+				SuppressStartupBanner="TRUE"

+				DebugInformationFormat="4"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalOptions="/MACHINE:I386"

+				AdditionalDependencies="..\..\masmx86\gvmat32.obj ..\..\masmx86\inffas32.obj"

+				OutputFile=".\DebugDll\zlibwapi.dll"

+				LinkIncremental="2"

+				SuppressStartupBanner="TRUE"

+				ModuleDefinitionFile=".\zlibvc.def"

+				GenerateDebugInformation="TRUE"

+				ProgramDatabaseFile=".\DebugDll/zlibwapi.pdb"

+				SubSystem="2"

+				ImportLibrary=".\DebugDll/zlibwapi.lib"/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="_DEBUG"

+				MkTypLibCompatible="TRUE"

+				SuppressStartupBanner="TRUE"

+				TargetEnvironment="1"

+				TypeLibraryName=".\DebugDll/zlibvc.tlb"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="_DEBUG"

+				Culture="1036"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+			<Tool

+				Name="VCWebDeploymentTool"/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutAsm|Win32"

+			OutputDirectory=".\zlibDllWithoutAsm"

+			IntermediateDirectory=".\zlibDllWithoutAsm"

+			ConfigurationType="2"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="FALSE"

+			WholeProgramOptimization="TRUE">

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32,ZLIB_WINAPI"

+				StringPooling="TRUE"

+				ExceptionHandling="FALSE"

+				RuntimeLibrary="0"

+				EnableFunctionLevelLinking="TRUE"

+				PrecompiledHeaderFile=".\zlibDllWithoutAsm/zlibvc.pch"

+				AssemblerOutput="2"

+				AssemblerListingLocation=".\zlibDllWithoutAsm/"

+				ObjectFile=".\zlibDllWithoutAsm/"

+				ProgramDataBaseFileName=".\zlibDllWithoutAsm/"

+				BrowseInformation="1"

+				WarningLevel="3"

+				SuppressStartupBanner="TRUE"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalOptions="/MACHINE:I386"

+				AdditionalDependencies="crtdll.lib"

+				OutputFile=".\zlibDllWithoutAsm\zlibwapi.dll"

+				LinkIncremental="1"

+				SuppressStartupBanner="TRUE"

+				IgnoreAllDefaultLibraries="TRUE"

+				ModuleDefinitionFile=".\zlibvc.def"

+				ProgramDatabaseFile=".\zlibDllWithoutAsm/zlibwapi.pdb"

+				GenerateMapFile="TRUE"

+				MapFileName=".\zlibDllWithoutAsm/zlibwapi.map"

+				SubSystem="2"

+				OptimizeForWindows98="1"

+				ImportLibrary=".\zlibDllWithoutAsm/zlibwapi.lib"/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="NDEBUG"

+				MkTypLibCompatible="TRUE"

+				SuppressStartupBanner="TRUE"

+				TargetEnvironment="1"

+				TypeLibraryName=".\zlibDllWithoutAsm/zlibvc.tlb"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="NDEBUG"

+				Culture="1036"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+			<Tool

+				Name="VCWebDeploymentTool"/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutCrtdll|Win32"

+			OutputDirectory=".\zlibDllWithoutCrtDll"

+			IntermediateDirectory=".\zlibDllWithoutCrtDll"

+			ConfigurationType="2"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="FALSE"

+			WholeProgramOptimization="TRUE">

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32,ZLIB_WINAPI,ASMV,ASMINF"

+				StringPooling="TRUE"

+				ExceptionHandling="FALSE"

+				RuntimeLibrary="0"

+				EnableFunctionLevelLinking="TRUE"

+				PrecompiledHeaderFile=".\zlibDllWithoutCrtDll/zlibvc.pch"

+				AssemblerOutput="2"

+				AssemblerListingLocation=".\zlibDllWithoutCrtDll/"

+				ObjectFile=".\zlibDllWithoutCrtDll/"

+				ProgramDataBaseFileName=".\zlibDllWithoutCrtDll/"

+				BrowseInformation="1"

+				WarningLevel="3"

+				SuppressStartupBanner="TRUE"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalOptions="/MACHINE:I386"

+				AdditionalDependencies="..\..\masmx86\gvmat32.obj ..\..\masmx86\inffas32.obj "

+				OutputFile=".\zlibDllWithoutCrtDll\zlibwapi.dll"

+				LinkIncremental="1"

+				SuppressStartupBanner="TRUE"

+				IgnoreAllDefaultLibraries="FALSE"

+				ModuleDefinitionFile=".\zlibvc.def"

+				ProgramDatabaseFile=".\zlibDllWithoutCrtDll/zlibwapi.pdb"

+				GenerateMapFile="TRUE"

+				MapFileName=".\zlibDllWithoutCrtDll/zlibwapi.map"

+				SubSystem="2"

+				OptimizeForWindows98="1"

+				ImportLibrary=".\zlibDllWithoutCrtDll/zlibwapi.lib"/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="NDEBUG"

+				MkTypLibCompatible="TRUE"

+				SuppressStartupBanner="TRUE"

+				TargetEnvironment="1"

+				TypeLibraryName=".\zlibDllWithoutCrtDll/zlibvc.tlb"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="NDEBUG"

+				Culture="1036"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+			<Tool

+				Name="VCWebDeploymentTool"/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseAxp|Win32"

+			OutputDirectory=".\zlibvc__"

+			IntermediateDirectory=".\zlibvc__"

+			ConfigurationType="2"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="FALSE"

+			WholeProgramOptimization="TRUE">

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32,ZLIB_WINAPI"

+				StringPooling="TRUE"

+				ExceptionHandling="FALSE"

+				RuntimeLibrary="0"

+				EnableFunctionLevelLinking="TRUE"

+				PrecompiledHeaderFile=".\zlibvc__/zlibvc.pch"

+				AssemblerOutput="2"

+				AssemblerListingLocation=".\zlibvc__/"

+				ObjectFile=".\zlibvc__/"

+				ProgramDataBaseFileName=".\zlibvc__/"

+				BrowseInformation="1"

+				WarningLevel="3"

+				SuppressStartupBanner="TRUE"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="crtdll.lib"

+				OutputFile="zlibvc__\zlibwapi.dll"

+				LinkIncremental="1"

+				SuppressStartupBanner="TRUE"

+				IgnoreAllDefaultLibraries="TRUE"

+				ModuleDefinitionFile=".\zlibvc.def"

+				ProgramDatabaseFile=".\zlibvc__/zlibwapi.pdb"

+				GenerateMapFile="TRUE"

+				MapFileName=".\zlibvc__/zlibwapi.map"

+				SubSystem="2"

+				ImportLibrary=".\zlibvc__/zlibwapi.lib"/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="NDEBUG"

+				MkTypLibCompatible="TRUE"

+				SuppressStartupBanner="TRUE"

+				TargetEnvironment="1"

+				TypeLibraryName=".\zlibvc__/zlibvc.tlb"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="NDEBUG"

+				Culture="1036"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+			<Tool

+				Name="VCWebDeploymentTool"/>

+		</Configuration>

+		<Configuration

+			Name="Release|Win32"

+			OutputDirectory=".\ReleaseDll"

+			IntermediateDirectory=".\ReleaseDll"

+			ConfigurationType="2"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="FALSE"

+			WholeProgramOptimization="TRUE">

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32,ZLIB_WINAPI,ASMV,ASMINF"

+				StringPooling="TRUE"

+				ExceptionHandling="FALSE"

+				RuntimeLibrary="0"

+				EnableFunctionLevelLinking="TRUE"

+				PrecompiledHeaderFile=".\ReleaseDll/zlibvc.pch"

+				AssemblerOutput="2"

+				AssemblerListingLocation=".\ReleaseDll/"

+				ObjectFile=".\ReleaseDll/"

+				ProgramDataBaseFileName=".\ReleaseDll/"

+				BrowseInformation="1"

+				WarningLevel="3"

+				SuppressStartupBanner="TRUE"/>

+			<Tool

+				Name="VCCustomBuildTool"/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalOptions="/MACHINE:I386"

+				AdditionalDependencies="..\..\masmx86\gvmat32.obj ..\..\masmx86\inffas32.obj crtdll.lib"

+				OutputFile=".\ReleaseDll\zlibwapi.dll"

+				LinkIncremental="1"

+				SuppressStartupBanner="TRUE"

+				IgnoreAllDefaultLibraries="TRUE"

+				ModuleDefinitionFile=".\zlibvc.def"

+				ProgramDatabaseFile=".\ReleaseDll/zlibwapi.pdb"

+				GenerateMapFile="TRUE"

+				MapFileName=".\ReleaseDll/zlibwapi.map"

+				SubSystem="2"

+				OptimizeForWindows98="1"

+				ImportLibrary=".\ReleaseDll/zlibwapi.lib"/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="NDEBUG"

+				MkTypLibCompatible="TRUE"

+				SuppressStartupBanner="TRUE"

+				TargetEnvironment="1"

+				TypeLibraryName=".\Release/zlibvc.tlb"/>

+			<Tool

+				Name="VCPostBuildEventTool"/>

+			<Tool

+				Name="VCPreBuildEventTool"/>

+			<Tool

+				Name="VCPreLinkEventTool"/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="NDEBUG"

+				Culture="1036"/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"/>

+			<Tool

+				Name="VCWebDeploymentTool"/>

+		</Configuration>

+	</Configurations>

+	<Files>

+		<Filter

+			Name="Source Files"

+			Filter="cpp;c;cxx;rc;def;r;odl;hpj;bat;for;f90">

+			<File

+				RelativePath="..\..\..\adler32.c">

+			</File>

+			<File

+				RelativePath="..\..\..\compress.c">

+			</File>

+			<File

+				RelativePath="..\..\..\crc32.c">

+			</File>

+			<File

+				RelativePath="..\..\..\deflate.c">

+			</File>

+			<File

+				RelativePath="..\..\masmx86\gvmat32c.c">

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|Win32"

+					ExcludedFromBuild="TRUE">

+					<Tool

+						Name="VCCLCompilerTool"/>

+				</FileConfiguration>

+			</File>

+			<File

+				RelativePath="..\..\..\gzio.c">

+			</File>

+			<File

+				RelativePath="..\..\..\infback.c">

+			</File>

+			<File

+				RelativePath="..\..\..\inffast.c">

+			</File>

+			<File

+				RelativePath="..\..\..\inflate.c">

+			</File>

+			<File

+				RelativePath="..\..\..\inftrees.c">

+			</File>

+			<File

+				RelativePath="..\..\minizip\ioapi.c">

+			</File>

+			<File

+				RelativePath="..\..\minizip\iowin32.c">

+			</File>

+			<File

+				RelativePath="..\..\..\trees.c">

+			</File>

+			<File

+				RelativePath="..\..\..\uncompr.c">

+			</File>

+			<File

+				RelativePath="..\..\minizip\unzip.c">

+				<FileConfiguration

+					Name="Release|Win32">

+					<Tool

+						Name="VCCLCompilerTool"

+						AdditionalIncludeDirectories=""

+						PreprocessorDefinitions="ZLIB_INTERNAL"/>

+				</FileConfiguration>

+			</File>

+			<File

+				RelativePath="..\..\minizip\zip.c">

+				<FileConfiguration

+					Name="Release|Win32">

+					<Tool

+						Name="VCCLCompilerTool"

+						AdditionalIncludeDirectories=""

+						PreprocessorDefinitions="ZLIB_INTERNAL"/>

+				</FileConfiguration>

+			</File>

+			<File

+				RelativePath=".\zlib.rc">

+			</File>

+			<File

+				RelativePath=".\zlibvc.def">

+			</File>

+			<File

+				RelativePath="..\..\..\zutil.c">

+			</File>

+		</Filter>

+		<Filter

+			Name="Header Files"

+			Filter="h;hpp;hxx;hm;inl;fi;fd">

+			<File

+				RelativePath="..\..\..\deflate.h">

+			</File>

+			<File

+				RelativePath="..\..\..\infblock.h">

+			</File>

+			<File

+				RelativePath="..\..\..\infcodes.h">

+			</File>

+			<File

+				RelativePath="..\..\..\inffast.h">

+			</File>

+			<File

+				RelativePath="..\..\..\inftrees.h">

+			</File>

+			<File

+				RelativePath="..\..\..\infutil.h">

+			</File>

+			<File

+				RelativePath="..\..\..\zconf.h">

+			</File>

+			<File

+				RelativePath="..\..\..\zlib.h">

+			</File>

+			<File

+				RelativePath="..\..\..\zutil.h">

+			</File>

+		</Filter>

+		<Filter

+			Name="Resource Files"

+			Filter="ico;cur;bmp;dlg;rc2;rct;bin;cnt;rtf;gif;jpg;jpeg;jpe">

+		</Filter>

+	</Files>

+	<Globals>

+	</Globals>

+</VisualStudioProject>

diff --git a/gs/zlib/contrib/vstudio/vc8/miniunz.vcproj b/gs/zlib/contrib/vstudio/vc8/miniunz.vcproj
new file mode 100644
index 000000000..4af53e8a3
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc8/miniunz.vcproj
@@ -0,0 +1,566 @@
+<?xml version="1.0" encoding="Windows-1252"?>

+<VisualStudioProject

+	ProjectType="Visual C++"

+	Version="8,00"

+	Name="miniunz"

+	ProjectGUID="{C52F9E7B-498A-42BE-8DB4-85A15694382A}"

+	Keyword="Win32Proj"

+	>

+	<Platforms>

+		<Platform

+			Name="Win32"

+		/>

+		<Platform

+			Name="x64"

+		/>

+		<Platform

+			Name="Itanium"

+		/>

+	</Platforms>

+	<ToolFiles>

+	</ToolFiles>

+	<Configurations>

+		<Configuration

+			Name="Debug|Win32"

+			OutputDirectory="x86\MiniUnzip$(ConfigurationName)"

+			IntermediateDirectory="x86\MiniUnzip$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="WIN32;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;_DEBUG;_CONSOLE"

+				MinimalRebuild="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="1"

+				BufferSecurityCheck="false"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="4"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x86\ZlibDllDebug\zlibwapi.lib"

+				OutputFile="$(OutDir)/miniunz.exe"

+				LinkIncremental="2"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/miniunz.pdb"

+				SubSystem="1"

+				TargetMachine="1"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|x64"

+			OutputDirectory="x64\MiniUnzip$(ConfigurationName)"

+			IntermediateDirectory="x64\MiniUnzip$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="3"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;_DEBUG;_CONSOLE;WIN64"

+				MinimalRebuild="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x64\ZlibDllDebug\zlibwapi.lib"

+				OutputFile="$(OutDir)/miniunz.exe"

+				LinkIncremental="2"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/miniunz.pdb"

+				SubSystem="1"

+				TargetMachine="17"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|Itanium"

+			OutputDirectory="ia64\MiniUnzip$(ConfigurationName)"

+			IntermediateDirectory="ia64\MiniUnzip$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;_DEBUG;_CONSOLE;WIN64"

+				MinimalRebuild="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="ia64\ZlibDllDebug\zlibwapi.lib"

+				OutputFile="$(OutDir)/miniunz.exe"

+				LinkIncremental="2"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/miniunz.pdb"

+				SubSystem="1"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Win32"

+			OutputDirectory="x86\MiniUnzip$(ConfigurationName)"

+			IntermediateDirectory="x86\MiniUnzip$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="WIN32;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;NDEBUG;_CONSOLE"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="0"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x86\ZlibDllRelease\zlibwapi.lib"

+				OutputFile="$(OutDir)/miniunz.exe"

+				LinkIncremental="1"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="1"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|x64"

+			OutputDirectory="x64\MiniUnzip$(ConfigurationName)"

+			IntermediateDirectory="x64\MiniUnzip$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="3"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;NDEBUG;_CONSOLE;WIN64"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x64\ZlibDllRelease\zlibwapi.lib"

+				OutputFile="$(OutDir)/miniunz.exe"

+				LinkIncremental="1"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="17"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Itanium"

+			OutputDirectory="ia64\MiniUnzip$(ConfigurationName)"

+			IntermediateDirectory="ia64\MiniUnzip$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;NDEBUG;_CONSOLE;WIN64"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="ia64\ZlibDllRelease\zlibwapi.lib"

+				OutputFile="$(OutDir)/miniunz.exe"

+				LinkIncremental="1"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+	</Configurations>

+	<References>

+	</References>

+	<Files>

+		<Filter

+			Name="Source Files"

+			Filter="cpp;c;cxx;def;odl;idl;hpj;bat;asm"

+			>

+			<File

+				RelativePath="..\..\minizip\miniunz.c"

+				>

+			</File>

+		</Filter>

+		<Filter

+			Name="Header Files"

+			Filter="h;hpp;hxx;hm;inl;inc"

+			>

+		</Filter>

+		<Filter

+			Name="Resource Files"

+			Filter="rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe"

+			>

+		</Filter>

+	</Files>

+	<Globals>

+	</Globals>

+</VisualStudioProject>

diff --git a/gs/zlib/contrib/vstudio/vc8/minizip.vcproj b/gs/zlib/contrib/vstudio/vc8/minizip.vcproj
new file mode 100644
index 000000000..85f64c4d2
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc8/minizip.vcproj
@@ -0,0 +1,563 @@
+<?xml version="1.0" encoding="Windows-1252"?>

+<VisualStudioProject

+	ProjectType="Visual C++"

+	Version="8,00"

+	Name="minizip"

+	ProjectGUID="{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}"

+	Keyword="Win32Proj"

+	>

+	<Platforms>

+		<Platform

+			Name="Win32"

+		/>

+		<Platform

+			Name="x64"

+		/>

+		<Platform

+			Name="Itanium"

+		/>

+	</Platforms>

+	<ToolFiles>

+	</ToolFiles>

+	<Configurations>

+		<Configuration

+			Name="Debug|Win32"

+			OutputDirectory="x86\MiniZip$(ConfigurationName)"

+			IntermediateDirectory="x86\MiniZip$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="WIN32;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;_DEBUG;_CONSOLE"

+				MinimalRebuild="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="1"

+				BufferSecurityCheck="false"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="4"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x86\ZlibDllDebug\zlibwapi.lib"

+				OutputFile="$(OutDir)/minizip.exe"

+				LinkIncremental="2"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/minizip.pdb"

+				SubSystem="1"

+				TargetMachine="1"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|x64"

+			OutputDirectory="x64\$(ConfigurationName)"

+			IntermediateDirectory="x64\$(ConfigurationName)"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="3"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;_DEBUG;_CONSOLE;WIN64"

+				MinimalRebuild="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x64\ZlibDllDebug\zlibwapi.lib"

+				OutputFile="$(OutDir)/minizip.exe"

+				LinkIncremental="2"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/minizip.pdb"

+				SubSystem="1"

+				TargetMachine="17"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|Itanium"

+			OutputDirectory="ia64\$(ConfigurationName)"

+			IntermediateDirectory="ia64\$(ConfigurationName)"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;_DEBUG;_CONSOLE;WIN64"

+				MinimalRebuild="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="ia64\ZlibDllDebug\zlibwapi.lib"

+				OutputFile="$(OutDir)/minizip.exe"

+				LinkIncremental="2"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/minizip.pdb"

+				SubSystem="1"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Win32"

+			OutputDirectory="x86\MiniZip$(ConfigurationName)"

+			IntermediateDirectory="x86\MiniZip$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="WIN32;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;NDEBUG;_CONSOLE"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="0"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x86\ZlibDllRelease\zlibwapi.lib"

+				OutputFile="$(OutDir)/minizip.exe"

+				LinkIncremental="1"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="1"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|x64"

+			OutputDirectory="x64\$(ConfigurationName)"

+			IntermediateDirectory="x64\$(ConfigurationName)"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="3"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;NDEBUG;_CONSOLE;WIN64"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x64\ZlibDllRelease\zlibwapi.lib"

+				OutputFile="$(OutDir)/minizip.exe"

+				LinkIncremental="1"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="17"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Itanium"

+			OutputDirectory="ia64\$(ConfigurationName)"

+			IntermediateDirectory="ia64\$(ConfigurationName)"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;NDEBUG;_CONSOLE;WIN64"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="ia64\ZlibDllRelease\zlibwapi.lib"

+				OutputFile="$(OutDir)/minizip.exe"

+				LinkIncremental="1"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+	</Configurations>

+	<References>

+	</References>

+	<Files>

+		<Filter

+			Name="Source Files"

+			Filter="cpp;c;cxx;def;odl;idl;hpj;bat;asm"

+			>

+			<File

+				RelativePath="..\..\minizip\minizip.c"

+				>

+			</File>

+		</Filter>

+		<Filter

+			Name="Header Files"

+			Filter="h;hpp;hxx;hm;inl;inc"

+			>

+		</Filter>

+		<Filter

+			Name="Resource Files"

+			Filter="rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe"

+			>

+		</Filter>

+	</Files>

+	<Globals>

+	</Globals>

+</VisualStudioProject>

diff --git a/gs/zlib/contrib/vstudio/vc8/testzlib.vcproj b/gs/zlib/contrib/vstudio/vc8/testzlib.vcproj
new file mode 100644
index 000000000..68c353991
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc8/testzlib.vcproj
@@ -0,0 +1,948 @@
+<?xml version="1.0" encoding="Windows-1252"?>

+<VisualStudioProject

+	ProjectType="Visual C++"

+	Version="8,00"

+	Name="testzlib"

+	ProjectGUID="{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}"

+	RootNamespace="testzlib"

+	Keyword="Win32Proj"

+	>

+	<Platforms>

+		<Platform

+			Name="Win32"

+		/>

+		<Platform

+			Name="x64"

+		/>

+		<Platform

+			Name="Itanium"

+		/>

+	</Platforms>

+	<ToolFiles>

+	</ToolFiles>

+	<Configurations>

+		<Configuration

+			Name="Debug|Win32"

+			OutputDirectory="x86\TestZlib$(ConfigurationName)"

+			IntermediateDirectory="x86\TestZlib$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\.."

+				PreprocessorDefinitions="ASMV;ASMINF;WIN32;ZLIB_WINAPI;_DEBUG;_CONSOLE;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE"

+				MinimalRebuild="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="1"

+				BufferSecurityCheck="false"

+				UsePrecompiledHeader="0"

+				AssemblerOutput="4"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="4"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="..\..\masmx86\gvmat32.obj ..\..\masmx86\inffas32.obj"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="2"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/testzlib.pdb"

+				SubSystem="1"

+				TargetMachine="1"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|x64"

+			OutputDirectory="x64\TestZlib$(ConfigurationName)"

+			IntermediateDirectory="x64\TestZlib$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				AdditionalIncludeDirectories="..\..\.."

+				PreprocessorDefinitions="ASMV;ASMINF;WIN32;ZLIB_WINAPI;_DEBUG;_CONSOLE;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				AssemblerListingLocation="$(IntDir)\"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="..\..\masmx64\gvmat64.obj ..\..\masmx64\inffasx64.obj"

+				GenerateManifest="false"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|Itanium"

+			OutputDirectory="ia64\TestZlib$(ConfigurationName)"

+			IntermediateDirectory="ia64\TestZlib$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\.."

+				PreprocessorDefinitions="ZLIB_WINAPI;_DEBUG;_CONSOLE;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;WIN64"

+				MinimalRebuild="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				UsePrecompiledHeader="0"

+				AssemblerOutput="4"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="2"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/testzlib.pdb"

+				SubSystem="1"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutAsm|Win32"

+			OutputDirectory="x86\TestZlib$(ConfigurationName)"

+			IntermediateDirectory="x86\TestZlib$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			CharacterSet="2"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\.."

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;NDEBUG;_CONSOLE;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="0"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="1"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="1"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutAsm|x64"

+			OutputDirectory="x64\TestZlib$(ConfigurationName)"

+			IntermediateDirectory="x64\TestZlib$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				AdditionalIncludeDirectories="..\..\.."

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;NDEBUG;_CONSOLE;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				AssemblerListingLocation="$(IntDir)\"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies=""

+				GenerateManifest="false"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutAsm|Itanium"

+			OutputDirectory="ia64\TestZlib$(ConfigurationName)"

+			IntermediateDirectory="ia64\TestZlib$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			CharacterSet="2"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\.."

+				PreprocessorDefinitions="ZLIB_WINAPI;NDEBUG;_CONSOLE;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;WIN64"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="1"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Win32"

+			OutputDirectory="x86\TestZlib$(ConfigurationName)"

+			IntermediateDirectory="x86\TestZlib$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			CharacterSet="2"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\.."

+				PreprocessorDefinitions="ASMV;ASMINF;WIN32;ZLIB_WINAPI;NDEBUG;_CONSOLE;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="0"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="..\..\masmx86\gvmat32.obj ..\..\masmx86\inffas32.obj"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="1"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="1"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|x64"

+			OutputDirectory="x64\TestZlib$(ConfigurationName)"

+			IntermediateDirectory="x64\TestZlib$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				AdditionalIncludeDirectories="..\..\.."

+				PreprocessorDefinitions="ASMV;ASMINF;WIN32;ZLIB_WINAPI;NDEBUG;_CONSOLE;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				AssemblerListingLocation="$(IntDir)\"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="..\..\masmx64\gvmat64.obj ..\..\masmx64\inffasx64.obj"

+				GenerateManifest="false"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Itanium"

+			OutputDirectory="ia64\TestZlib$(ConfigurationName)"

+			IntermediateDirectory="ia64\TestZlib$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			CharacterSet="2"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\.."

+				PreprocessorDefinitions="ZLIB_WINAPI;NDEBUG;_CONSOLE;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;WIN64"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="1"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+	</Configurations>

+	<References>

+	</References>

+	<Files>

+		<Filter

+			Name="Source Files"

+			Filter="cpp;c;cxx;def;odl;idl;hpj;bat;asm"

+			>

+			<File

+				RelativePath="..\..\..\adler32.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\compress.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\crc32.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\deflate.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\masmx86\gvmat32c.c"

+				>

+				<FileConfiguration

+					Name="Debug|x64"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Debug|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|x64"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|x64"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Debug|Win64 (AMD64)"

+					ExcludedFromBuild="TRUE"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Win64 (AMD64)"

+					ExcludedFromBuild="TRUE"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseAsm|Win64 (AMD64)"

+					ExcludedFromBuild="TRUE"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+			</File>

+			<File

+				RelativePath="..\..\..\infback.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\masmx64\inffas8664.c"

+				>

+				<FileConfiguration

+					Name="Debug|Win32"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Debug|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|Win32"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Win32"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+			</File>

+			<File

+				RelativePath="..\..\..\inffast.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\inflate.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\inftrees.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\testzlib\testzlib.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\trees.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\uncompr.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\zutil.c"

+				>

+			</File>

+		</Filter>

+		<Filter

+			Name="Header Files"

+			Filter="h;hpp;hxx;hm;inl;inc"

+			>

+		</Filter>

+		<Filter

+			Name="Resource Files"

+			Filter="rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe"

+			>

+		</Filter>

+	</Files>

+	<Globals>

+	</Globals>

+</VisualStudioProject>

diff --git a/gs/zlib/contrib/vstudio/vc8/testzlibdll.vcproj b/gs/zlib/contrib/vstudio/vc8/testzlibdll.vcproj
new file mode 100644
index 000000000..f38ab5e08
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc8/testzlibdll.vcproj
@@ -0,0 +1,567 @@
+<?xml version="1.0" encoding="Windows-1252"?>

+<VisualStudioProject

+	ProjectType="Visual C++"

+	Version="8,00"

+	Name="TestZlibDll"

+	ProjectGUID="{C52F9E7B-498A-42BE-8DB4-85A15694366A}"

+	Keyword="Win32Proj"

+	SignManifests="true"

+	>

+	<Platforms>

+		<Platform

+			Name="Win32"

+		/>

+		<Platform

+			Name="x64"

+		/>

+		<Platform

+			Name="Itanium"

+		/>

+	</Platforms>

+	<ToolFiles>

+	</ToolFiles>

+	<Configurations>

+		<Configuration

+			Name="Debug|Win32"

+			OutputDirectory="x86\TestZlibDll$(ConfigurationName)"

+			IntermediateDirectory="x86\TestZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="WIN32;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;_DEBUG;_CONSOLE"

+				MinimalRebuild="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="1"

+				BufferSecurityCheck="false"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="4"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x86\ZlibDllDebug\zlibwapi.lib"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="2"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/testzlib.pdb"

+				SubSystem="1"

+				TargetMachine="1"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|x64"

+			OutputDirectory="x64\TestZlibDll$(ConfigurationName)"

+			IntermediateDirectory="x64\TestZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="3"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;_DEBUG;_CONSOLE;WIN64"

+				MinimalRebuild="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x64\ZlibDllDebug\zlibwapi.lib"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="2"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/testzlib.pdb"

+				SubSystem="1"

+				TargetMachine="17"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|Itanium"

+			OutputDirectory="ia64\TestZlibDll$(ConfigurationName)"

+			IntermediateDirectory="ia64\TestZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;_DEBUG;_CONSOLE;WIN64"

+				MinimalRebuild="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="ia64\ZlibDllDebug\zlibwapi.lib"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="2"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/testzlib.pdb"

+				SubSystem="1"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Win32"

+			OutputDirectory="x86\TestZlibDll$(ConfigurationName)"

+			IntermediateDirectory="x86\TestZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="WIN32;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;NDEBUG;_CONSOLE"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="0"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x86\ZlibDllRelease\zlibwapi.lib"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="1"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="1"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|x64"

+			OutputDirectory="x64\TestZlibDll$(ConfigurationName)"

+			IntermediateDirectory="x64\TestZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="3"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;NDEBUG;_CONSOLE;WIN64"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="x64\ZlibDllRelease\zlibwapi.lib"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="1"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="17"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Itanium"

+			OutputDirectory="ia64\TestZlibDll$(ConfigurationName)"

+			IntermediateDirectory="ia64\TestZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="1"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			CharacterSet="2"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="2"

+				InlineFunctionExpansion="1"

+				OmitFramePointers="true"

+				AdditionalIncludeDirectories="..\..\..;..\..\minizip"

+				PreprocessorDefinitions="_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;NDEBUG;_CONSOLE;WIN64"

+				StringPooling="true"

+				BasicRuntimeChecks="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				UsePrecompiledHeader="0"

+				AssemblerListingLocation="$(IntDir)\"

+				WarningLevel="3"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="ia64\ZlibDllRelease\zlibwapi.lib"

+				OutputFile="$(OutDir)/testzlib.exe"

+				LinkIncremental="1"

+				GenerateManifest="false"

+				GenerateDebugInformation="true"

+				SubSystem="1"

+				OptimizeReferences="2"

+				EnableCOMDATFolding="2"

+				OptimizeForWindows98="1"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+	</Configurations>

+	<References>

+	</References>

+	<Files>

+		<Filter

+			Name="Source Files"

+			Filter="cpp;c;cxx;def;odl;idl;hpj;bat;asm"

+			>

+			<File

+				RelativePath="..\..\testzlib\testzlib.c"

+				>

+			</File>

+		</Filter>

+		<Filter

+			Name="Header Files"

+			Filter="h;hpp;hxx;hm;inl;inc"

+			>

+		</Filter>

+		<Filter

+			Name="Resource Files"

+			Filter="rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe"

+			>

+		</Filter>

+	</Files>

+	<Globals>

+	</Globals>

+</VisualStudioProject>

diff --git a/gs/zlib/contrib/vstudio/vc8/zlib.rc b/gs/zlib/contrib/vstudio/vc8/zlib.rc
new file mode 100644
index 000000000..72cb8b4c3
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc8/zlib.rc
@@ -0,0 +1,32 @@
+#include <windows.h>

+

+#define IDR_VERSION1  1

+IDR_VERSION1	VERSIONINFO	MOVEABLE IMPURE LOADONCALL DISCARDABLE

+  FILEVERSION	 1,2,3,0

+  PRODUCTVERSION 1,2,3,0

+  FILEFLAGSMASK	VS_FFI_FILEFLAGSMASK

+  FILEFLAGS	0

+  FILEOS	VOS_DOS_WINDOWS32

+  FILETYPE	VFT_DLL

+  FILESUBTYPE	0	// not used

+BEGIN

+  BLOCK "StringFileInfo"

+  BEGIN

+    BLOCK "040904E4"

+    //language ID = U.S. English, char set = Windows, Multilingual

+

+    BEGIN

+      VALUE "FileDescription", "zlib data compression library\0"

+      VALUE "FileVersion",	"1.2.3.0\0"

+      VALUE "InternalName",	"zlib\0"

+      VALUE "OriginalFilename",	"zlib.dll\0"

+      VALUE "ProductName",	"ZLib.DLL\0"

+      VALUE "Comments","DLL support by Alessandro Iacopetti & Gilles Vollant\0"

+      VALUE "LegalCopyright", "(C) 1995-2003 Jean-loup Gailly & Mark Adler\0"

+    END

+  END

+  BLOCK "VarFileInfo"

+  BEGIN

+    VALUE "Translation", 0x0409, 1252

+  END

+END

diff --git a/gs/zlib/contrib/vstudio/vc8/zlibstat.vcproj b/gs/zlib/contrib/vstudio/vc8/zlibstat.vcproj
new file mode 100644
index 000000000..fb97037ac
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc8/zlibstat.vcproj
@@ -0,0 +1,870 @@
+<?xml version="1.0" encoding="Windows-1252"?>

+<VisualStudioProject

+	ProjectType="Visual C++"

+	Version="8,00"

+	Name="zlibstat"

+	ProjectGUID="{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}"

+	>

+	<Platforms>

+		<Platform

+			Name="Win32"

+		/>

+		<Platform

+			Name="x64"

+		/>

+		<Platform

+			Name="Itanium"

+		/>

+	</Platforms>

+	<ToolFiles>

+	</ToolFiles>

+	<Configurations>

+		<Configuration

+			Name="Debug|Win32"

+			OutputDirectory="x86\ZlibStat$(ConfigurationName)"

+			IntermediateDirectory="x86\ZlibStat$(ConfigurationName)\Tmp"

+			ConfigurationType="4"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE"

+				ExceptionHandling="0"

+				RuntimeLibrary="1"

+				BufferSecurityCheck="false"

+				PrecompiledHeaderFile="$(IntDir)/zlibstat.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="1"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="/MACHINE:X86 /NODEFAULTLIB"

+				OutputFile="$(OutDir)\zlibstat.lib"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|x64"

+			OutputDirectory="x64\ZlibStat$(ConfigurationName)"

+			IntermediateDirectory="x64\ZlibStat$(ConfigurationName)\Tmp"

+			ConfigurationType="4"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="3"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="ZLIB_WINAPI;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;WIN64"

+				ExceptionHandling="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				PrecompiledHeaderFile="$(IntDir)/zlibstat.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="1"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="/MACHINE:AMD64 /NODEFAULTLIB"

+				OutputFile="$(OutDir)\zlibstat.lib"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|Itanium"

+			OutputDirectory="ia64\ZlibStat$(ConfigurationName)"

+			IntermediateDirectory="ia64\ZlibStat$(ConfigurationName)\Tmp"

+			ConfigurationType="4"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="ZLIB_WINAPI;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;WIN64"

+				ExceptionHandling="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				PrecompiledHeaderFile="$(IntDir)/zlibstat.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+				Detect64BitPortabilityProblems="true"

+				DebugInformationFormat="1"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="/MACHINE:IA64 /NODEFAULTLIB"

+				OutputFile="$(OutDir)\zlibstat.lib"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Win32"

+			OutputDirectory="x86\ZlibStat$(ConfigurationName)"

+			IntermediateDirectory="x86\ZlibStat$(ConfigurationName)\Tmp"

+			ConfigurationType="4"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ASMV;ASMINF"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="0"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibstat.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="/MACHINE:X86 /NODEFAULTLIB"

+				AdditionalDependencies="..\..\masmx86\gvmat32.obj ..\..\masmx86\inffas32.obj "

+				OutputFile="$(OutDir)\zlibstat.lib"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|x64"

+			OutputDirectory="x64\ZlibStat$(ConfigurationName)"

+			IntermediateDirectory="x64\ZlibStat$(ConfigurationName)\Tmp"

+			ConfigurationType="4"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="3"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="ZLIB_WINAPI;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;ASMV;ASMINF;WIN64"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibstat.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="/MACHINE:AMD64 /NODEFAULTLIB"

+				AdditionalDependencies="..\..\masmx64\gvmat64.obj ..\..\masmx64\inffasx64.obj "

+				OutputFile="$(OutDir)\zlibstat.lib"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Itanium"

+			OutputDirectory="ia64\ZlibStat$(ConfigurationName)"

+			IntermediateDirectory="ia64\ZlibStat$(ConfigurationName)\Tmp"

+			ConfigurationType="4"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="ZLIB_WINAPI;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;WIN64"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibstat.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="/MACHINE:IA64 /NODEFAULTLIB"

+				OutputFile="$(OutDir)\zlibstat.lib"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutAsm|Win32"

+			OutputDirectory="x86\ZlibStat$(ConfigurationName)"

+			IntermediateDirectory="x86\ZlibStat$(ConfigurationName)\Tmp"

+			ConfigurationType="4"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32;ZLIB_WINAPI;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="0"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibstat.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="/MACHINE:X86 /NODEFAULTLIB"

+				OutputFile="$(OutDir)\zlibstat.lib"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutAsm|x64"

+			OutputDirectory="x64\ZlibStat$(ConfigurationName)"

+			IntermediateDirectory="x64\ZlibStat$(ConfigurationName)\Tmp"

+			ConfigurationType="4"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="3"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="ZLIB_WINAPI;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;WIN64"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibstat.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="/MACHINE:AMD64 /NODEFAULTLIB"

+				OutputFile="$(OutDir)\zlibstat.lib"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutAsm|Itanium"

+			OutputDirectory="ia64\ZlibStat$(ConfigurationName)"

+			IntermediateDirectory="ia64\ZlibStat$(ConfigurationName)\Tmp"

+			ConfigurationType="4"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				TargetEnvironment="2"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="ZLIB_WINAPI;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_DEPRECATE;WIN64"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibstat.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLibrarianTool"

+				AdditionalOptions="/MACHINE:IA64 /NODEFAULTLIB"

+				OutputFile="$(OutDir)\zlibstat.lib"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+	</Configurations>

+	<References>

+	</References>

+	<Files>

+		<Filter

+			Name="Source Files"

+			>

+			<File

+				RelativePath="..\..\..\adler32.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\compress.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\crc32.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\deflate.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\masmx86\gvmat32c.c"

+				>

+				<FileConfiguration

+					Name="Debug|x64"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Debug|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|x64"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|x64"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+			</File>

+			<File

+				RelativePath="..\..\..\gzio.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\infback.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\masmx64\inffas8664.c"

+				>

+				<FileConfiguration

+					Name="Debug|Win32"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Debug|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Win32"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|Win32"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+			</File>

+			<File

+				RelativePath="..\..\..\inffast.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\inflate.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\inftrees.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\minizip\ioapi.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\trees.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\uncompr.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\minizip\unzip.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\minizip\zip.c"

+				>

+			</File>

+			<File

+				RelativePath=".\zlib.rc"

+				>

+			</File>

+			<File

+				RelativePath=".\zlibvc.def"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\zutil.c"

+				>

+			</File>

+		</Filter>

+	</Files>

+	<Globals>

+	</Globals>

+</VisualStudioProject>

diff --git a/gs/zlib/contrib/vstudio/vc8/zlibvc.def b/gs/zlib/contrib/vstudio/vc8/zlibvc.def
new file mode 100644
index 000000000..a40e71541
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc8/zlibvc.def
@@ -0,0 +1,92 @@
+

+VERSION		1.23

+

+HEAPSIZE	1048576,8192

+

+EXPORTS

+        adler32                                  @1

+        compress                                 @2

+        crc32                                    @3

+        deflate                                  @4

+        deflateCopy                              @5

+        deflateEnd                               @6

+        deflateInit2_                            @7

+        deflateInit_                             @8

+        deflateParams                            @9

+        deflateReset                             @10

+        deflateSetDictionary                     @11

+        gzclose                                  @12

+        gzdopen                                  @13

+        gzerror                                  @14

+        gzflush                                  @15

+        gzopen                                   @16

+        gzread                                   @17

+        gzwrite                                  @18

+        inflate                                  @19

+        inflateEnd                               @20

+        inflateInit2_                            @21

+        inflateInit_                             @22

+        inflateReset                             @23

+        inflateSetDictionary                     @24

+        inflateSync                              @25

+        uncompress                               @26

+        zlibVersion                              @27

+        gzprintf                                 @28

+        gzputc                                   @29

+        gzgetc                                   @30

+        gzseek                                   @31

+        gzrewind                                 @32

+        gztell                                   @33

+        gzeof                                    @34

+        gzsetparams                              @35

+        zError                                   @36

+        inflateSyncPoint                         @37

+        get_crc_table                            @38

+        compress2                                @39

+        gzputs                                   @40

+        gzgets                                   @41

+        inflateCopy                              @42

+        inflateBackInit_                         @43

+        inflateBack                              @44

+        inflateBackEnd                           @45

+        compressBound                            @46

+        deflateBound                             @47

+        gzclearerr                               @48

+        gzungetc                                 @49

+        zlibCompileFlags                         @50

+        deflatePrime                             @51

+

+        unzOpen                                  @61

+        unzClose                                 @62

+        unzGetGlobalInfo                         @63

+        unzGetCurrentFileInfo                    @64

+        unzGoToFirstFile                         @65

+        unzGoToNextFile                          @66

+        unzOpenCurrentFile                       @67

+        unzReadCurrentFile                       @68

+        unzOpenCurrentFile3                      @69

+        unztell                                  @70

+        unzeof                                   @71

+        unzCloseCurrentFile                      @72

+        unzGetGlobalComment                      @73

+        unzStringFileNameCompare                 @74

+        unzLocateFile                            @75

+        unzGetLocalExtrafield                    @76

+        unzOpen2                                 @77

+        unzOpenCurrentFile2                      @78

+        unzOpenCurrentFilePassword               @79

+

+        zipOpen                                  @80

+        zipOpenNewFileInZip                      @81

+        zipWriteInFileInZip                      @82

+        zipCloseFileInZip                        @83

+        zipClose                                 @84

+        zipOpenNewFileInZip2                     @86

+        zipCloseFileInZipRaw                     @87

+        zipOpen2                                 @88

+        zipOpenNewFileInZip3                     @89

+

+        unzGetFilePos                            @100

+        unzGoToFilePos                           @101

+

+        fill_win32_filefunc                      @110

diff --git a/gs/zlib/contrib/vstudio/vc8/zlibvc.sln b/gs/zlib/contrib/vstudio/vc8/zlibvc.sln
new file mode 100644
index 000000000..a815a5549
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc8/zlibvc.sln
@@ -0,0 +1,144 @@
+

+Microsoft Visual Studio Solution File, Format Version 9.00

+# Visual Studio 2005

+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "zlibvc", "zlibvc.vcproj", "{8FD826F8-3739-44E6-8CC8-997122E53B8D}"

+EndProject

+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "zlibstat", "zlibstat.vcproj", "{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}"

+EndProject

+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "testzlib", "testzlib.vcproj", "{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}"

+EndProject

+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "TestZlibDll", "testzlibdll.vcproj", "{C52F9E7B-498A-42BE-8DB4-85A15694366A}"

+	ProjectSection(ProjectDependencies) = postProject

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D} = {8FD826F8-3739-44E6-8CC8-997122E53B8D}

+	EndProjectSection

+EndProject

+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "minizip", "minizip.vcproj", "{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}"

+	ProjectSection(ProjectDependencies) = postProject

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D} = {8FD826F8-3739-44E6-8CC8-997122E53B8D}

+	EndProjectSection

+EndProject

+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "miniunz", "miniunz.vcproj", "{C52F9E7B-498A-42BE-8DB4-85A15694382A}"

+	ProjectSection(ProjectDependencies) = postProject

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D} = {8FD826F8-3739-44E6-8CC8-997122E53B8D}

+	EndProjectSection

+EndProject

+Global

+	GlobalSection(SolutionConfigurationPlatforms) = preSolution

+		Debug|Itanium = Debug|Itanium

+		Debug|Win32 = Debug|Win32

+		Debug|x64 = Debug|x64

+		Release|Itanium = Release|Itanium

+		Release|Win32 = Release|Win32

+		Release|x64 = Release|x64

+		ReleaseWithoutAsm|Itanium = ReleaseWithoutAsm|Itanium

+		ReleaseWithoutAsm|Win32 = ReleaseWithoutAsm|Win32

+		ReleaseWithoutAsm|x64 = ReleaseWithoutAsm|x64

+	EndGlobalSection

+	GlobalSection(ProjectConfigurationPlatforms) = postSolution

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Debug|Itanium.ActiveCfg = Debug|Itanium

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Debug|Itanium.Build.0 = Debug|Itanium

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Debug|Win32.ActiveCfg = Debug|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Debug|Win32.Build.0 = Debug|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Debug|x64.ActiveCfg = Debug|x64

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Debug|x64.Build.0 = Debug|x64

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Release|Itanium.ActiveCfg = Release|Itanium

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Release|Itanium.Build.0 = Release|Itanium

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Release|Win32.ActiveCfg = Release|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Release|Win32.Build.0 = Release|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.Release|x64.ActiveCfg = ReleaseWithoutAsm|x64

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+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.ReleaseWithoutAsm|Itanium.Build.0 = ReleaseWithoutAsm|Itanium

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.ReleaseWithoutAsm|Win32.ActiveCfg = ReleaseWithoutAsm|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.ReleaseWithoutAsm|Win32.Build.0 = ReleaseWithoutAsm|Win32

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.ReleaseWithoutAsm|x64.ActiveCfg = ReleaseWithoutAsm|x64

+		{8FD826F8-3739-44E6-8CC8-997122E53B8D}.ReleaseWithoutAsm|x64.Build.0 = ReleaseWithoutAsm|x64

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.Debug|Itanium.ActiveCfg = Debug|Itanium

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.Debug|Itanium.Build.0 = Debug|Itanium

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.Debug|Win32.ActiveCfg = Debug|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.Debug|Win32.Build.0 = Debug|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.Debug|x64.ActiveCfg = Debug|x64

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+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.Release|x64.ActiveCfg = Release|x64

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.Release|x64.Build.0 = Release|x64

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseWithoutAsm|Itanium.ActiveCfg = ReleaseWithoutAsm|Itanium

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseWithoutAsm|Itanium.Build.0 = ReleaseWithoutAsm|Itanium

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseWithoutAsm|Win32.ActiveCfg = ReleaseWithoutAsm|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseWithoutAsm|Win32.Build.0 = ReleaseWithoutAsm|Win32

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseWithoutAsm|x64.ActiveCfg = ReleaseWithoutAsm|x64

+		{745DEC58-EBB3-47A9-A9B8-4C6627C01BF8}.ReleaseWithoutAsm|x64.Build.0 = ReleaseWithoutAsm|x64

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Debug|Itanium.ActiveCfg = Debug|Itanium

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Debug|Itanium.Build.0 = Debug|Itanium

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Debug|Win32.ActiveCfg = Debug|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Debug|Win32.Build.0 = Debug|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Debug|x64.ActiveCfg = Debug|x64

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Debug|x64.Build.0 = Debug|x64

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Release|Itanium.ActiveCfg = Release|Itanium

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Release|Itanium.Build.0 = Release|Itanium

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Release|Win32.ActiveCfg = Release|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Release|Win32.Build.0 = Release|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Release|x64.ActiveCfg = Release|x64

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.Release|x64.Build.0 = Release|x64

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm|Itanium.ActiveCfg = ReleaseWithoutAsm|Itanium

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm|Itanium.Build.0 = ReleaseWithoutAsm|Itanium

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm|Win32.ActiveCfg = ReleaseWithoutAsm|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm|Win32.Build.0 = ReleaseWithoutAsm|Win32

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm|x64.ActiveCfg = ReleaseWithoutAsm|x64

+		{AA6666AA-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm|x64.Build.0 = ReleaseWithoutAsm|x64

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Debug|Itanium.ActiveCfg = Debug|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Debug|Itanium.Build.0 = Debug|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Debug|Win32.ActiveCfg = Debug|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Debug|Win32.Build.0 = Debug|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Debug|x64.ActiveCfg = Debug|x64

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Debug|x64.Build.0 = Debug|x64

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Release|Itanium.ActiveCfg = Release|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Release|Itanium.Build.0 = Release|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Release|Win32.ActiveCfg = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Release|Win32.Build.0 = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Release|x64.ActiveCfg = Release|x64

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.Release|x64.Build.0 = Release|x64

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.ReleaseWithoutAsm|Itanium.ActiveCfg = Release|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.ReleaseWithoutAsm|Itanium.Build.0 = Release|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.ReleaseWithoutAsm|Win32.ActiveCfg = Release|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694366A}.ReleaseWithoutAsm|x64.ActiveCfg = Release|Itanium

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Debug|Itanium.ActiveCfg = Debug|Itanium

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Debug|Itanium.Build.0 = Debug|Itanium

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Debug|Win32.ActiveCfg = Debug|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Debug|Win32.Build.0 = Debug|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Debug|x64.ActiveCfg = Debug|x64

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Debug|x64.Build.0 = Debug|x64

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Release|Itanium.ActiveCfg = Release|Itanium

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Release|Itanium.Build.0 = Release|Itanium

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Release|Win32.ActiveCfg = Release|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Release|Win32.Build.0 = Release|Win32

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Release|x64.ActiveCfg = Release|x64

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.Release|x64.Build.0 = Release|x64

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm|Itanium.ActiveCfg = Release|Itanium

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm|Itanium.Build.0 = Release|Itanium

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm|Win32.ActiveCfg = Release|Itanium

+		{48CDD9DC-E09F-4135-9C0C-4FE50C3C654B}.ReleaseWithoutAsm|x64.ActiveCfg = Release|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Debug|Itanium.ActiveCfg = Debug|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Debug|Itanium.Build.0 = Debug|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Debug|Win32.ActiveCfg = Debug|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Debug|Win32.Build.0 = Debug|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Debug|x64.ActiveCfg = Debug|x64

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Debug|x64.Build.0 = Debug|x64

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Release|Itanium.ActiveCfg = Release|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Release|Itanium.Build.0 = Release|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Release|Win32.ActiveCfg = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Release|Win32.Build.0 = Release|Win32

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Release|x64.ActiveCfg = Release|x64

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.Release|x64.Build.0 = Release|x64

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.ReleaseWithoutAsm|Itanium.ActiveCfg = Release|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.ReleaseWithoutAsm|Itanium.Build.0 = Release|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.ReleaseWithoutAsm|Win32.ActiveCfg = Release|Itanium

+		{C52F9E7B-498A-42BE-8DB4-85A15694382A}.ReleaseWithoutAsm|x64.ActiveCfg = Release|Itanium

+	EndGlobalSection

+	GlobalSection(SolutionProperties) = preSolution

+		HideSolutionNode = FALSE

+	EndGlobalSection

+EndGlobal

diff --git a/gs/zlib/contrib/vstudio/vc8/zlibvc.vcproj b/gs/zlib/contrib/vstudio/vc8/zlibvc.vcproj
new file mode 100644
index 000000000..e717011df
--- /dev/null
+++ b/gs/zlib/contrib/vstudio/vc8/zlibvc.vcproj
@@ -0,0 +1,1219 @@
+<?xml version="1.0" encoding="Windows-1252"?>

+<VisualStudioProject

+	ProjectType="Visual C++"

+	Version="8,00"

+	Name="zlibvc"

+	ProjectGUID="{8FD826F8-3739-44E6-8CC8-997122E53B8D}"

+	>

+	<Platforms>

+		<Platform

+			Name="Win32"

+		/>

+		<Platform

+			Name="x64"

+		/>

+		<Platform

+			Name="Itanium"

+		/>

+	</Platforms>

+	<ToolFiles>

+	</ToolFiles>

+	<Configurations>

+		<Configuration

+			Name="Debug|Win32"

+			OutputDirectory="x86\ZlibDll$(ConfigurationName)"

+			IntermediateDirectory="x86\ZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="2"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="_DEBUG"

+				MkTypLibCompatible="true"

+				SuppressStartupBanner="true"

+				TargetEnvironment="1"

+				TypeLibraryName="$(OutDir)/zlibvc.tlb"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32,_CRT_SECURE_NO_DEPRECATE,ZLIB_WINAPI,ASMV,ASMINF"

+				ExceptionHandling="0"

+				RuntimeLibrary="1"

+				BufferSecurityCheck="false"

+				PrecompiledHeaderFile="$(IntDir)/zlibvc.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				BrowseInformation="0"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+				DebugInformationFormat="4"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="_DEBUG"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalOptions="/MACHINE:I386"

+				AdditionalDependencies="..\..\masmx86\gvmat32.obj ..\..\masmx86\inffas32.obj"

+				OutputFile="$(OutDir)\zlibwapi.dll"

+				LinkIncremental="2"

+				SuppressStartupBanner="true"

+				GenerateManifest="false"

+				ModuleDefinitionFile=".\zlibvc.def"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/zlibwapi.pdb"

+				GenerateMapFile="true"

+				MapFileName="$(OutDir)/zlibwapi.map"

+				SubSystem="2"

+				ImportLibrary="$(OutDir)/zlibwapi.lib"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|x64"

+			OutputDirectory="x64\ZlibDll$(ConfigurationName)"

+			IntermediateDirectory="x64\ZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="2"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="_DEBUG"

+				MkTypLibCompatible="true"

+				SuppressStartupBanner="true"

+				TargetEnvironment="3"

+				TypeLibraryName="$(OutDir)/zlibvc.tlb"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32,_CRT_SECURE_NO_DEPRECATE,ZLIB_WINAPI,ASMV,ASMINF;WIN64"

+				ExceptionHandling="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				PrecompiledHeaderFile="$(IntDir)/zlibvc.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				BrowseInformation="0"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="_DEBUG"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="..\..\masmx64\gvmat64.obj ..\..\masmx64\inffasx64.obj "

+				OutputFile="$(OutDir)\zlibwapi.dll"

+				LinkIncremental="2"

+				SuppressStartupBanner="true"

+				GenerateManifest="false"

+				ModuleDefinitionFile=".\zlibvc.def"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/zlibwapi.pdb"

+				GenerateMapFile="true"

+				MapFileName="$(OutDir)/zlibwapi.map"

+				SubSystem="2"

+				ImportLibrary="$(OutDir)/zlibwapi.lib"

+				TargetMachine="17"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Debug|Itanium"

+			OutputDirectory="ia64\ZlibDll$(ConfigurationName)"

+			IntermediateDirectory="ia64\ZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="2"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="_DEBUG"

+				MkTypLibCompatible="true"

+				SuppressStartupBanner="true"

+				TargetEnvironment="2"

+				TypeLibraryName="$(OutDir)/zlibvc.tlb"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				Optimization="0"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;WIN64"

+				ExceptionHandling="0"

+				RuntimeLibrary="3"

+				BufferSecurityCheck="false"

+				PrecompiledHeaderFile="$(IntDir)/zlibvc.pch"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				BrowseInformation="0"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+				DebugInformationFormat="3"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="_DEBUG"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)\zlibwapi.dll"

+				LinkIncremental="2"

+				SuppressStartupBanner="true"

+				GenerateManifest="false"

+				ModuleDefinitionFile=".\zlibvc.def"

+				GenerateDebugInformation="true"

+				ProgramDatabaseFile="$(OutDir)/zlibwapi.pdb"

+				GenerateMapFile="true"

+				MapFileName="$(OutDir)/zlibwapi.map"

+				SubSystem="2"

+				ImportLibrary="$(OutDir)/zlibwapi.lib"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutAsm|Win32"

+			OutputDirectory="x86\ZlibDll$(ConfigurationName)"

+			IntermediateDirectory="x86\ZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="2"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="NDEBUG"

+				MkTypLibCompatible="true"

+				SuppressStartupBanner="true"

+				TargetEnvironment="1"

+				TypeLibraryName="$(OutDir)/zlibvc.tlb"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32,_CRT_SECURE_NO_DEPRECATE,ZLIB_WINAPI"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibvc.pch"

+				AssemblerOutput="2"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				BrowseInformation="0"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="NDEBUG"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalOptions="/MACHINE:I386"

+				OutputFile="$(OutDir)\zlibwapi.dll"

+				LinkIncremental="1"

+				SuppressStartupBanner="true"

+				GenerateManifest="false"

+				IgnoreAllDefaultLibraries="false"

+				ModuleDefinitionFile=".\zlibvc.def"

+				ProgramDatabaseFile="$(OutDir)/zlibwapi.pdb"

+				GenerateMapFile="true"

+				MapFileName="$(OutDir)/zlibwapi.map"

+				SubSystem="2"

+				OptimizeForWindows98="1"

+				ImportLibrary="$(OutDir)/zlibwapi.lib"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutAsm|x64"

+			OutputDirectory="x64\ZlibDll$(ConfigurationName)"

+			IntermediateDirectory="x64\ZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="2"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="NDEBUG"

+				MkTypLibCompatible="true"

+				SuppressStartupBanner="true"

+				TargetEnvironment="3"

+				TypeLibraryName="$(OutDir)/zlibvc.tlb"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32,_CRT_SECURE_NO_DEPRECATE,ZLIB_WINAPI;WIN64"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibvc.pch"

+				AssemblerOutput="2"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				BrowseInformation="0"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="NDEBUG"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)\zlibwapi.dll"

+				LinkIncremental="1"

+				SuppressStartupBanner="true"

+				GenerateManifest="false"

+				IgnoreAllDefaultLibraries="false"

+				ModuleDefinitionFile=".\zlibvc.def"

+				ProgramDatabaseFile="$(OutDir)/zlibwapi.pdb"

+				GenerateMapFile="true"

+				MapFileName="$(OutDir)/zlibwapi.map"

+				SubSystem="2"

+				OptimizeForWindows98="1"

+				ImportLibrary="$(OutDir)/zlibwapi.lib"

+				TargetMachine="17"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="ReleaseWithoutAsm|Itanium"

+			OutputDirectory="ia64\ZlibDll$(ConfigurationName)"

+			IntermediateDirectory="ia64\ZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="2"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="NDEBUG"

+				MkTypLibCompatible="true"

+				SuppressStartupBanner="true"

+				TargetEnvironment="2"

+				TypeLibraryName="$(OutDir)/zlibvc.tlb"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32,_CRT_SECURE_NO_DEPRECATE,ZLIB_WINAPI;WIN64"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibvc.pch"

+				AssemblerOutput="2"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				BrowseInformation="0"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="NDEBUG"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)\zlibwapi.dll"

+				LinkIncremental="1"

+				SuppressStartupBanner="true"

+				GenerateManifest="false"

+				IgnoreAllDefaultLibraries="false"

+				ModuleDefinitionFile=".\zlibvc.def"

+				ProgramDatabaseFile="$(OutDir)/zlibwapi.pdb"

+				GenerateMapFile="true"

+				MapFileName="$(OutDir)/zlibwapi.map"

+				SubSystem="2"

+				OptimizeForWindows98="1"

+				ImportLibrary="$(OutDir)/zlibwapi.lib"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Win32"

+			OutputDirectory="x86\ZlibDll$(ConfigurationName)"

+			IntermediateDirectory="x86\ZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="2"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="NDEBUG"

+				MkTypLibCompatible="true"

+				SuppressStartupBanner="true"

+				TargetEnvironment="1"

+				TypeLibraryName="$(OutDir)/zlibvc.tlb"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="WIN32;_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;ASMV;ASMINF"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibvc.pch"

+				AssemblerOutput="2"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				BrowseInformation="0"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="NDEBUG"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalOptions="/MACHINE:I386"

+				AdditionalDependencies="..\..\masmx86\gvmat32.obj ..\..\masmx86\inffas32.obj "

+				OutputFile="$(OutDir)\zlibwapi.dll"

+				LinkIncremental="1"

+				SuppressStartupBanner="true"

+				GenerateManifest="false"

+				IgnoreAllDefaultLibraries="false"

+				ModuleDefinitionFile=".\zlibvc.def"

+				ProgramDatabaseFile="$(OutDir)/zlibwapi.pdb"

+				GenerateMapFile="true"

+				MapFileName="$(OutDir)/zlibwapi.map"

+				SubSystem="2"

+				OptimizeForWindows98="1"

+				ImportLibrary="$(OutDir)/zlibwapi.lib"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|x64"

+			OutputDirectory="x64\ZlibDll$(ConfigurationName)"

+			IntermediateDirectory="x64\ZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="2"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="NDEBUG"

+				MkTypLibCompatible="true"

+				SuppressStartupBanner="true"

+				TargetEnvironment="3"

+				TypeLibraryName="$(OutDir)/zlibvc.tlb"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;ASMV;ASMINF;WIN64"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibvc.pch"

+				AssemblerOutput="2"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				BrowseInformation="0"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="NDEBUG"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				AdditionalDependencies="..\..\masmx64\gvmat64.obj ..\..\masmx64\inffasx64.obj "

+				OutputFile="$(OutDir)\zlibwapi.dll"

+				LinkIncremental="1"

+				SuppressStartupBanner="true"

+				GenerateManifest="false"

+				IgnoreAllDefaultLibraries="false"

+				ModuleDefinitionFile=".\zlibvc.def"

+				ProgramDatabaseFile="$(OutDir)/zlibwapi.pdb"

+				GenerateMapFile="true"

+				MapFileName="$(OutDir)/zlibwapi.map"

+				SubSystem="2"

+				OptimizeForWindows98="1"

+				ImportLibrary="$(OutDir)/zlibwapi.lib"

+				TargetMachine="17"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+		<Configuration

+			Name="Release|Itanium"

+			OutputDirectory="ia64\ZlibDll$(ConfigurationName)"

+			IntermediateDirectory="ia64\ZlibDll$(ConfigurationName)\Tmp"

+			ConfigurationType="2"

+			InheritedPropertySheets="UpgradeFromVC70.vsprops"

+			UseOfMFC="0"

+			ATLMinimizesCRunTimeLibraryUsage="false"

+			WholeProgramOptimization="1"

+			>

+			<Tool

+				Name="VCPreBuildEventTool"

+			/>

+			<Tool

+				Name="VCCustomBuildTool"

+			/>

+			<Tool

+				Name="VCXMLDataGeneratorTool"

+			/>

+			<Tool

+				Name="VCWebServiceProxyGeneratorTool"

+			/>

+			<Tool

+				Name="VCMIDLTool"

+				PreprocessorDefinitions="NDEBUG"

+				MkTypLibCompatible="true"

+				SuppressStartupBanner="true"

+				TargetEnvironment="2"

+				TypeLibraryName="$(OutDir)/zlibvc.tlb"

+			/>

+			<Tool

+				Name="VCCLCompilerTool"

+				InlineFunctionExpansion="1"

+				AdditionalIncludeDirectories="..\..\..;..\..\masmx86"

+				PreprocessorDefinitions="_CRT_SECURE_NO_DEPRECATE;ZLIB_WINAPI;WIN64"

+				StringPooling="true"

+				ExceptionHandling="0"

+				RuntimeLibrary="2"

+				BufferSecurityCheck="false"

+				EnableFunctionLevelLinking="true"

+				PrecompiledHeaderFile="$(IntDir)/zlibvc.pch"

+				AssemblerOutput="2"

+				AssemblerListingLocation="$(IntDir)\"

+				ObjectFile="$(IntDir)\"

+				ProgramDataBaseFileName="$(OutDir)\"

+				BrowseInformation="0"

+				WarningLevel="3"

+				SuppressStartupBanner="true"

+			/>

+			<Tool

+				Name="VCManagedResourceCompilerTool"

+			/>

+			<Tool

+				Name="VCResourceCompilerTool"

+				PreprocessorDefinitions="NDEBUG"

+				Culture="1036"

+			/>

+			<Tool

+				Name="VCPreLinkEventTool"

+			/>

+			<Tool

+				Name="VCLinkerTool"

+				OutputFile="$(OutDir)\zlibwapi.dll"

+				LinkIncremental="1"

+				SuppressStartupBanner="true"

+				GenerateManifest="false"

+				IgnoreAllDefaultLibraries="false"

+				ModuleDefinitionFile=".\zlibvc.def"

+				ProgramDatabaseFile="$(OutDir)/zlibwapi.pdb"

+				GenerateMapFile="true"

+				MapFileName="$(OutDir)/zlibwapi.map"

+				SubSystem="2"

+				OptimizeForWindows98="1"

+				ImportLibrary="$(OutDir)/zlibwapi.lib"

+				TargetMachine="5"

+			/>

+			<Tool

+				Name="VCALinkTool"

+			/>

+			<Tool

+				Name="VCManifestTool"

+			/>

+			<Tool

+				Name="VCXDCMakeTool"

+			/>

+			<Tool

+				Name="VCBscMakeTool"

+			/>

+			<Tool

+				Name="VCFxCopTool"

+			/>

+			<Tool

+				Name="VCAppVerifierTool"

+			/>

+			<Tool

+				Name="VCWebDeploymentTool"

+			/>

+			<Tool

+				Name="VCPostBuildEventTool"

+			/>

+		</Configuration>

+	</Configurations>

+	<References>

+	</References>

+	<Files>

+		<Filter

+			Name="Source Files"

+			Filter="cpp;c;cxx;rc;def;r;odl;hpj;bat;for;f90"

+			>

+			<File

+				RelativePath="..\..\..\adler32.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\compress.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\crc32.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\deflate.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\masmx86\gvmat32c.c"

+				>

+				<FileConfiguration

+					Name="Debug|x64"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Debug|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|Win32"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|x64"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|x64"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+			</File>

+			<File

+				RelativePath="..\..\..\gzio.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\infback.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\masmx64\inffas8664.c"

+				>

+				<FileConfiguration

+					Name="Debug|Win32"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Debug|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|Win32"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="ReleaseWithoutAsm|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Win32"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Itanium"

+					ExcludedFromBuild="true"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+					/>

+				</FileConfiguration>

+			</File>

+			<File

+				RelativePath="..\..\..\inffast.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\inflate.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\inftrees.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\minizip\ioapi.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\minizip\iowin32.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\trees.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\uncompr.c"

+				>

+			</File>

+			<File

+				RelativePath="..\..\minizip\unzip.c"

+				>

+				<FileConfiguration

+					Name="Release|Win32"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+						AdditionalIncludeDirectories=""

+						PreprocessorDefinitions="ZLIB_INTERNAL"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|x64"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+						AdditionalIncludeDirectories=""

+						PreprocessorDefinitions="ZLIB_INTERNAL"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Itanium"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+						AdditionalIncludeDirectories=""

+						PreprocessorDefinitions="ZLIB_INTERNAL"

+					/>

+				</FileConfiguration>

+			</File>

+			<File

+				RelativePath="..\..\minizip\zip.c"

+				>

+				<FileConfiguration

+					Name="Release|Win32"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+						AdditionalIncludeDirectories=""

+						PreprocessorDefinitions="ZLIB_INTERNAL"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|x64"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+						AdditionalIncludeDirectories=""

+						PreprocessorDefinitions="ZLIB_INTERNAL"

+					/>

+				</FileConfiguration>

+				<FileConfiguration

+					Name="Release|Itanium"

+					>

+					<Tool

+						Name="VCCLCompilerTool"

+						AdditionalIncludeDirectories=""

+						PreprocessorDefinitions="ZLIB_INTERNAL"

+					/>

+				</FileConfiguration>

+			</File>

+			<File

+				RelativePath=".\zlib.rc"

+				>

+			</File>

+			<File

+				RelativePath=".\zlibvc.def"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\zutil.c"

+				>

+			</File>

+		</Filter>

+		<Filter

+			Name="Header Files"

+			Filter="h;hpp;hxx;hm;inl;fi;fd"

+			>

+			<File

+				RelativePath="..\..\..\deflate.h"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\infblock.h"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\infcodes.h"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\inffast.h"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\inftrees.h"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\infutil.h"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\zconf.h"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\zlib.h"

+				>

+			</File>

+			<File

+				RelativePath="..\..\..\zutil.h"

+				>

+			</File>

+		</Filter>

+		<Filter

+			Name="Resource Files"

+			Filter="ico;cur;bmp;dlg;rc2;rct;bin;cnt;rtf;gif;jpg;jpeg;jpe"

+			>

+		</Filter>

+	</Files>

+	<Globals>

+	</Globals>

+</VisualStudioProject>

diff --git a/gs/zlib/crc32.c b/gs/zlib/crc32.c
new file mode 100644
index 000000000..f658a9ef5
--- /dev/null
+++ b/gs/zlib/crc32.c
@@ -0,0 +1,423 @@
+/* crc32.c -- compute the CRC-32 of a data stream
+ * Copyright (C) 1995-2005 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ *
+ * Thanks to Rodney Brown <rbrown64@csc.com.au> for his contribution of faster
+ * CRC methods: exclusive-oring 32 bits of data at a time, and pre-computing
+ * tables for updating the shift register in one step with three exclusive-ors
+ * instead of four steps with four exclusive-ors.  This results in about a
+ * factor of two increase in speed on a Power PC G4 (PPC7455) using gcc -O3.
+ */
+
+/* @(#) $Id$ */
+
+/*
+  Note on the use of DYNAMIC_CRC_TABLE: there is no mutex or semaphore
+  protection on the static variables used to control the first-use generation
+  of the crc tables.  Therefore, if you #define DYNAMIC_CRC_TABLE, you should
+  first call get_crc_table() to initialize the tables before allowing more than
+  one thread to use crc32().
+ */
+
+#ifdef MAKECRCH
+#  include <stdio.h>
+#  ifndef DYNAMIC_CRC_TABLE
+#    define DYNAMIC_CRC_TABLE
+#  endif /* !DYNAMIC_CRC_TABLE */
+#endif /* MAKECRCH */
+
+#include "zutil.h"      /* for STDC and FAR definitions */
+
+#define local static
+
+/* Find a four-byte integer type for crc32_little() and crc32_big(). */
+#ifndef NOBYFOUR
+#  ifdef STDC           /* need ANSI C limits.h to determine sizes */
+#    include <limits.h>
+#    define BYFOUR
+#    if (UINT_MAX == 0xffffffffUL)
+       typedef unsigned int u4;
+#    else
+#      if (ULONG_MAX == 0xffffffffUL)
+         typedef unsigned long u4;
+#      else
+#        if (USHRT_MAX == 0xffffffffUL)
+           typedef unsigned short u4;
+#        else
+#          undef BYFOUR     /* can't find a four-byte integer type! */
+#        endif
+#      endif
+#    endif
+#  endif /* STDC */
+#endif /* !NOBYFOUR */
+
+/* Definitions for doing the crc four data bytes at a time. */
+#ifdef BYFOUR
+#  define REV(w) (((w)>>24)+(((w)>>8)&0xff00)+ \
+                (((w)&0xff00)<<8)+(((w)&0xff)<<24))
+   local unsigned long crc32_little OF((unsigned long,
+                        const unsigned char FAR *, unsigned));
+   local unsigned long crc32_big OF((unsigned long,
+                        const unsigned char FAR *, unsigned));
+#  define TBLS 8
+#else
+#  define TBLS 1
+#endif /* BYFOUR */
+
+/* Local functions for crc concatenation */
+local unsigned long gf2_matrix_times OF((unsigned long *mat,
+                                         unsigned long vec));
+local void gf2_matrix_square OF((unsigned long *square, unsigned long *mat));
+
+#ifdef DYNAMIC_CRC_TABLE
+
+local volatile int crc_table_empty = 1;
+local unsigned long FAR crc_table[TBLS][256];
+local void make_crc_table OF((void));
+#ifdef MAKECRCH
+   local void write_table OF((FILE *, const unsigned long FAR *));
+#endif /* MAKECRCH */
+/*
+  Generate tables for a byte-wise 32-bit CRC calculation on the polynomial:
+  x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x+1.
+
+  Polynomials over GF(2) are represented in binary, one bit per coefficient,
+  with the lowest powers in the most significant bit.  Then adding polynomials
+  is just exclusive-or, and multiplying a polynomial by x is a right shift by
+  one.  If we call the above polynomial p, and represent a byte as the
+  polynomial q, also with the lowest power in the most significant bit (so the
+  byte 0xb1 is the polynomial x^7+x^3+x+1), then the CRC is (q*x^32) mod p,
+  where a mod b means the remainder after dividing a by b.
+
+  This calculation is done using the shift-register method of multiplying and
+  taking the remainder.  The register is initialized to zero, and for each
+  incoming bit, x^32 is added mod p to the register if the bit is a one (where
+  x^32 mod p is p+x^32 = x^26+...+1), and the register is multiplied mod p by
+  x (which is shifting right by one and adding x^32 mod p if the bit shifted
+  out is a one).  We start with the highest power (least significant bit) of
+  q and repeat for all eight bits of q.
+
+  The first table is simply the CRC of all possible eight bit values.  This is
+  all the information needed to generate CRCs on data a byte at a time for all
+  combinations of CRC register values and incoming bytes.  The remaining tables
+  allow for word-at-a-time CRC calculation for both big-endian and little-
+  endian machines, where a word is four bytes.
+*/
+local void make_crc_table()
+{
+    unsigned long c;
+    int n, k;
+    unsigned long poly;                 /* polynomial exclusive-or pattern */
+    /* terms of polynomial defining this crc (except x^32): */
+    static volatile int first = 1;      /* flag to limit concurrent making */
+    static const unsigned char p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26};
+
+    /* See if another task is already doing this (not thread-safe, but better
+       than nothing -- significantly reduces duration of vulnerability in
+       case the advice about DYNAMIC_CRC_TABLE is ignored) */
+    if (first) {
+        first = 0;
+
+        /* make exclusive-or pattern from polynomial (0xedb88320UL) */
+        poly = 0UL;
+        for (n = 0; n < sizeof(p)/sizeof(unsigned char); n++)
+            poly |= 1UL << (31 - p[n]);
+
+        /* generate a crc for every 8-bit value */
+        for (n = 0; n < 256; n++) {
+            c = (unsigned long)n;
+            for (k = 0; k < 8; k++)
+                c = c & 1 ? poly ^ (c >> 1) : c >> 1;
+            crc_table[0][n] = c;
+        }
+
+#ifdef BYFOUR
+        /* generate crc for each value followed by one, two, and three zeros,
+           and then the byte reversal of those as well as the first table */
+        for (n = 0; n < 256; n++) {
+            c = crc_table[0][n];
+            crc_table[4][n] = REV(c);
+            for (k = 1; k < 4; k++) {
+                c = crc_table[0][c & 0xff] ^ (c >> 8);
+                crc_table[k][n] = c;
+                crc_table[k + 4][n] = REV(c);
+            }
+        }
+#endif /* BYFOUR */
+
+        crc_table_empty = 0;
+    }
+    else {      /* not first */
+        /* wait for the other guy to finish (not efficient, but rare) */
+        while (crc_table_empty)
+            ;
+    }
+
+#ifdef MAKECRCH
+    /* write out CRC tables to crc32.h */
+    {
+        FILE *out;
+
+        out = fopen("crc32.h", "w");
+        if (out == NULL) return;
+        fprintf(out, "/* crc32.h -- tables for rapid CRC calculation\n");
+        fprintf(out, " * Generated automatically by crc32.c\n */\n\n");
+        fprintf(out, "local const unsigned long FAR ");
+        fprintf(out, "crc_table[TBLS][256] =\n{\n  {\n");
+        write_table(out, crc_table[0]);
+#  ifdef BYFOUR
+        fprintf(out, "#ifdef BYFOUR\n");
+        for (k = 1; k < 8; k++) {
+            fprintf(out, "  },\n  {\n");
+            write_table(out, crc_table[k]);
+        }
+        fprintf(out, "#endif\n");
+#  endif /* BYFOUR */
+        fprintf(out, "  }\n};\n");
+        fclose(out);
+    }
+#endif /* MAKECRCH */
+}
+
+#ifdef MAKECRCH
+local void write_table(out, table)
+    FILE *out;
+    const unsigned long FAR *table;
+{
+    int n;
+
+    for (n = 0; n < 256; n++)
+        fprintf(out, "%s0x%08lxUL%s", n % 5 ? "" : "    ", table[n],
+                n == 255 ? "\n" : (n % 5 == 4 ? ",\n" : ", "));
+}
+#endif /* MAKECRCH */
+
+#else /* !DYNAMIC_CRC_TABLE */
+/* ========================================================================
+ * Tables of CRC-32s of all single-byte values, made by make_crc_table().
+ */
+#include "crc32.h"
+#endif /* DYNAMIC_CRC_TABLE */
+
+/* =========================================================================
+ * This function can be used by asm versions of crc32()
+ */
+const unsigned long FAR * ZEXPORT get_crc_table()
+{
+#ifdef DYNAMIC_CRC_TABLE
+    if (crc_table_empty)
+        make_crc_table();
+#endif /* DYNAMIC_CRC_TABLE */
+    return (const unsigned long FAR *)crc_table;
+}
+
+/* ========================================================================= */
+#define DO1 crc = crc_table[0][((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8)
+#define DO8 DO1; DO1; DO1; DO1; DO1; DO1; DO1; DO1
+
+/* ========================================================================= */
+unsigned long ZEXPORT crc32(crc, buf, len)
+    unsigned long crc;
+    const unsigned char FAR *buf;
+    unsigned len;
+{
+    if (buf == Z_NULL) return 0UL;
+
+#ifdef DYNAMIC_CRC_TABLE
+    if (crc_table_empty)
+        make_crc_table();
+#endif /* DYNAMIC_CRC_TABLE */
+
+#ifdef BYFOUR
+    if (sizeof(void *) == sizeof(ptrdiff_t)) {
+        u4 endian;
+
+        endian = 1;
+        if (*((unsigned char *)(&endian)))
+            return crc32_little(crc, buf, len);
+        else
+            return crc32_big(crc, buf, len);
+    }
+#endif /* BYFOUR */
+    crc = crc ^ 0xffffffffUL;
+    while (len >= 8) {
+        DO8;
+        len -= 8;
+    }
+    if (len) do {
+        DO1;
+    } while (--len);
+    return crc ^ 0xffffffffUL;
+}
+
+#ifdef BYFOUR
+
+/* ========================================================================= */
+#define DOLIT4 c ^= *buf4++; \
+        c = crc_table[3][c & 0xff] ^ crc_table[2][(c >> 8) & 0xff] ^ \
+            crc_table[1][(c >> 16) & 0xff] ^ crc_table[0][c >> 24]
+#define DOLIT32 DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4
+
+/* ========================================================================= */
+local unsigned long crc32_little(crc, buf, len)
+    unsigned long crc;
+    const unsigned char FAR *buf;
+    unsigned len;
+{
+    register u4 c;
+    register const u4 FAR *buf4;
+
+    c = (u4)crc;
+    c = ~c;
+    while (len && ((ptrdiff_t)buf & 3)) {
+        c = crc_table[0][(c ^ *buf++) & 0xff] ^ (c >> 8);
+        len--;
+    }
+
+    buf4 = (const u4 FAR *)(const void FAR *)buf;
+    while (len >= 32) {
+        DOLIT32;
+        len -= 32;
+    }
+    while (len >= 4) {
+        DOLIT4;
+        len -= 4;
+    }
+    buf = (const unsigned char FAR *)buf4;
+
+    if (len) do {
+        c = crc_table[0][(c ^ *buf++) & 0xff] ^ (c >> 8);
+    } while (--len);
+    c = ~c;
+    return (unsigned long)c;
+}
+
+/* ========================================================================= */
+#define DOBIG4 c ^= *++buf4; \
+        c = crc_table[4][c & 0xff] ^ crc_table[5][(c >> 8) & 0xff] ^ \
+            crc_table[6][(c >> 16) & 0xff] ^ crc_table[7][c >> 24]
+#define DOBIG32 DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4
+
+/* ========================================================================= */
+local unsigned long crc32_big(crc, buf, len)
+    unsigned long crc;
+    const unsigned char FAR *buf;
+    unsigned len;
+{
+    register u4 c;
+    register const u4 FAR *buf4;
+
+    c = REV((u4)crc);
+    c = ~c;
+    while (len && ((ptrdiff_t)buf & 3)) {
+        c = crc_table[4][(c >> 24) ^ *buf++] ^ (c << 8);
+        len--;
+    }
+
+    buf4 = (const u4 FAR *)(const void FAR *)buf;
+    buf4--;
+    while (len >= 32) {
+        DOBIG32;
+        len -= 32;
+    }
+    while (len >= 4) {
+        DOBIG4;
+        len -= 4;
+    }
+    buf4++;
+    buf = (const unsigned char FAR *)buf4;
+
+    if (len) do {
+        c = crc_table[4][(c >> 24) ^ *buf++] ^ (c << 8);
+    } while (--len);
+    c = ~c;
+    return (unsigned long)(REV(c));
+}
+
+#endif /* BYFOUR */
+
+#define GF2_DIM 32      /* dimension of GF(2) vectors (length of CRC) */
+
+/* ========================================================================= */
+local unsigned long gf2_matrix_times(mat, vec)
+    unsigned long *mat;
+    unsigned long vec;
+{
+    unsigned long sum;
+
+    sum = 0;
+    while (vec) {
+        if (vec & 1)
+            sum ^= *mat;
+        vec >>= 1;
+        mat++;
+    }
+    return sum;
+}
+
+/* ========================================================================= */
+local void gf2_matrix_square(square, mat)
+    unsigned long *square;
+    unsigned long *mat;
+{
+    int n;
+
+    for (n = 0; n < GF2_DIM; n++)
+        square[n] = gf2_matrix_times(mat, mat[n]);
+}
+
+/* ========================================================================= */
+uLong ZEXPORT crc32_combine(crc1, crc2, len2)
+    uLong crc1;
+    uLong crc2;
+    z_off_t len2;
+{
+    int n;
+    unsigned long row;
+    unsigned long even[GF2_DIM];    /* even-power-of-two zeros operator */
+    unsigned long odd[GF2_DIM];     /* odd-power-of-two zeros operator */
+
+    /* degenerate case */
+    if (len2 == 0)
+        return crc1;
+
+    /* put operator for one zero bit in odd */
+    odd[0] = 0xedb88320L;           /* CRC-32 polynomial */
+    row = 1;
+    for (n = 1; n < GF2_DIM; n++) {
+        odd[n] = row;
+        row <<= 1;
+    }
+
+    /* put operator for two zero bits in even */
+    gf2_matrix_square(even, odd);
+
+    /* put operator for four zero bits in odd */
+    gf2_matrix_square(odd, even);
+
+    /* apply len2 zeros to crc1 (first square will put the operator for one
+       zero byte, eight zero bits, in even) */
+    do {
+        /* apply zeros operator for this bit of len2 */
+        gf2_matrix_square(even, odd);
+        if (len2 & 1)
+            crc1 = gf2_matrix_times(even, crc1);
+        len2 >>= 1;
+
+        /* if no more bits set, then done */
+        if (len2 == 0)
+            break;
+
+        /* another iteration of the loop with odd and even swapped */
+        gf2_matrix_square(odd, even);
+        if (len2 & 1)
+            crc1 = gf2_matrix_times(odd, crc1);
+        len2 >>= 1;
+
+        /* if no more bits set, then done */
+    } while (len2 != 0);
+
+    /* return combined crc */
+    crc1 ^= crc2;
+    return crc1;
+}
diff --git a/gs/zlib/crc32.h b/gs/zlib/crc32.h
new file mode 100644
index 000000000..8053b6117
--- /dev/null
+++ b/gs/zlib/crc32.h
@@ -0,0 +1,441 @@
+/* crc32.h -- tables for rapid CRC calculation
+ * Generated automatically by crc32.c
+ */
+
+local const unsigned long FAR crc_table[TBLS][256] =
+{
+  {
+    0x00000000UL, 0x77073096UL, 0xee0e612cUL, 0x990951baUL, 0x076dc419UL,
+    0x706af48fUL, 0xe963a535UL, 0x9e6495a3UL, 0x0edb8832UL, 0x79dcb8a4UL,
+    0xe0d5e91eUL, 0x97d2d988UL, 0x09b64c2bUL, 0x7eb17cbdUL, 0xe7b82d07UL,
+    0x90bf1d91UL, 0x1db71064UL, 0x6ab020f2UL, 0xf3b97148UL, 0x84be41deUL,
+    0x1adad47dUL, 0x6ddde4ebUL, 0xf4d4b551UL, 0x83d385c7UL, 0x136c9856UL,
+    0x646ba8c0UL, 0xfd62f97aUL, 0x8a65c9ecUL, 0x14015c4fUL, 0x63066cd9UL,
+    0xfa0f3d63UL, 0x8d080df5UL, 0x3b6e20c8UL, 0x4c69105eUL, 0xd56041e4UL,
+    0xa2677172UL, 0x3c03e4d1UL, 0x4b04d447UL, 0xd20d85fdUL, 0xa50ab56bUL,
+    0x35b5a8faUL, 0x42b2986cUL, 0xdbbbc9d6UL, 0xacbcf940UL, 0x32d86ce3UL,
+    0x45df5c75UL, 0xdcd60dcfUL, 0xabd13d59UL, 0x26d930acUL, 0x51de003aUL,
+    0xc8d75180UL, 0xbfd06116UL, 0x21b4f4b5UL, 0x56b3c423UL, 0xcfba9599UL,
+    0xb8bda50fUL, 0x2802b89eUL, 0x5f058808UL, 0xc60cd9b2UL, 0xb10be924UL,
+    0x2f6f7c87UL, 0x58684c11UL, 0xc1611dabUL, 0xb6662d3dUL, 0x76dc4190UL,
+    0x01db7106UL, 0x98d220bcUL, 0xefd5102aUL, 0x71b18589UL, 0x06b6b51fUL,
+    0x9fbfe4a5UL, 0xe8b8d433UL, 0x7807c9a2UL, 0x0f00f934UL, 0x9609a88eUL,
+    0xe10e9818UL, 0x7f6a0dbbUL, 0x086d3d2dUL, 0x91646c97UL, 0xe6635c01UL,
+    0x6b6b51f4UL, 0x1c6c6162UL, 0x856530d8UL, 0xf262004eUL, 0x6c0695edUL,
+    0x1b01a57bUL, 0x8208f4c1UL, 0xf50fc457UL, 0x65b0d9c6UL, 0x12b7e950UL,
+    0x8bbeb8eaUL, 0xfcb9887cUL, 0x62dd1ddfUL, 0x15da2d49UL, 0x8cd37cf3UL,
+    0xfbd44c65UL, 0x4db26158UL, 0x3ab551ceUL, 0xa3bc0074UL, 0xd4bb30e2UL,
+    0x4adfa541UL, 0x3dd895d7UL, 0xa4d1c46dUL, 0xd3d6f4fbUL, 0x4369e96aUL,
+    0x346ed9fcUL, 0xad678846UL, 0xda60b8d0UL, 0x44042d73UL, 0x33031de5UL,
+    0xaa0a4c5fUL, 0xdd0d7cc9UL, 0x5005713cUL, 0x270241aaUL, 0xbe0b1010UL,
+    0xc90c2086UL, 0x5768b525UL, 0x206f85b3UL, 0xb966d409UL, 0xce61e49fUL,
+    0x5edef90eUL, 0x29d9c998UL, 0xb0d09822UL, 0xc7d7a8b4UL, 0x59b33d17UL,
+    0x2eb40d81UL, 0xb7bd5c3bUL, 0xc0ba6cadUL, 0xedb88320UL, 0x9abfb3b6UL,
+    0x03b6e20cUL, 0x74b1d29aUL, 0xead54739UL, 0x9dd277afUL, 0x04db2615UL,
+    0x73dc1683UL, 0xe3630b12UL, 0x94643b84UL, 0x0d6d6a3eUL, 0x7a6a5aa8UL,
+    0xe40ecf0bUL, 0x9309ff9dUL, 0x0a00ae27UL, 0x7d079eb1UL, 0xf00f9344UL,
+    0x8708a3d2UL, 0x1e01f268UL, 0x6906c2feUL, 0xf762575dUL, 0x806567cbUL,
+    0x196c3671UL, 0x6e6b06e7UL, 0xfed41b76UL, 0x89d32be0UL, 0x10da7a5aUL,
+    0x67dd4accUL, 0xf9b9df6fUL, 0x8ebeeff9UL, 0x17b7be43UL, 0x60b08ed5UL,
+    0xd6d6a3e8UL, 0xa1d1937eUL, 0x38d8c2c4UL, 0x4fdff252UL, 0xd1bb67f1UL,
+    0xa6bc5767UL, 0x3fb506ddUL, 0x48b2364bUL, 0xd80d2bdaUL, 0xaf0a1b4cUL,
+    0x36034af6UL, 0x41047a60UL, 0xdf60efc3UL, 0xa867df55UL, 0x316e8eefUL,
+    0x4669be79UL, 0xcb61b38cUL, 0xbc66831aUL, 0x256fd2a0UL, 0x5268e236UL,
+    0xcc0c7795UL, 0xbb0b4703UL, 0x220216b9UL, 0x5505262fUL, 0xc5ba3bbeUL,
+    0xb2bd0b28UL, 0x2bb45a92UL, 0x5cb36a04UL, 0xc2d7ffa7UL, 0xb5d0cf31UL,
+    0x2cd99e8bUL, 0x5bdeae1dUL, 0x9b64c2b0UL, 0xec63f226UL, 0x756aa39cUL,
+    0x026d930aUL, 0x9c0906a9UL, 0xeb0e363fUL, 0x72076785UL, 0x05005713UL,
+    0x95bf4a82UL, 0xe2b87a14UL, 0x7bb12baeUL, 0x0cb61b38UL, 0x92d28e9bUL,
+    0xe5d5be0dUL, 0x7cdcefb7UL, 0x0bdbdf21UL, 0x86d3d2d4UL, 0xf1d4e242UL,
+    0x68ddb3f8UL, 0x1fda836eUL, 0x81be16cdUL, 0xf6b9265bUL, 0x6fb077e1UL,
+    0x18b74777UL, 0x88085ae6UL, 0xff0f6a70UL, 0x66063bcaUL, 0x11010b5cUL,
+    0x8f659effUL, 0xf862ae69UL, 0x616bffd3UL, 0x166ccf45UL, 0xa00ae278UL,
+    0xd70dd2eeUL, 0x4e048354UL, 0x3903b3c2UL, 0xa7672661UL, 0xd06016f7UL,
+    0x4969474dUL, 0x3e6e77dbUL, 0xaed16a4aUL, 0xd9d65adcUL, 0x40df0b66UL,
+    0x37d83bf0UL, 0xa9bcae53UL, 0xdebb9ec5UL, 0x47b2cf7fUL, 0x30b5ffe9UL,
+    0xbdbdf21cUL, 0xcabac28aUL, 0x53b39330UL, 0x24b4a3a6UL, 0xbad03605UL,
+    0xcdd70693UL, 0x54de5729UL, 0x23d967bfUL, 0xb3667a2eUL, 0xc4614ab8UL,
+    0x5d681b02UL, 0x2a6f2b94UL, 0xb40bbe37UL, 0xc30c8ea1UL, 0x5a05df1bUL,
+    0x2d02ef8dUL
+#ifdef BYFOUR
+  },
+  {
+    0x00000000UL, 0x191b3141UL, 0x32366282UL, 0x2b2d53c3UL, 0x646cc504UL,
+    0x7d77f445UL, 0x565aa786UL, 0x4f4196c7UL, 0xc8d98a08UL, 0xd1c2bb49UL,
+    0xfaefe88aUL, 0xe3f4d9cbUL, 0xacb54f0cUL, 0xb5ae7e4dUL, 0x9e832d8eUL,
+    0x87981ccfUL, 0x4ac21251UL, 0x53d92310UL, 0x78f470d3UL, 0x61ef4192UL,
+    0x2eaed755UL, 0x37b5e614UL, 0x1c98b5d7UL, 0x05838496UL, 0x821b9859UL,
+    0x9b00a918UL, 0xb02dfadbUL, 0xa936cb9aUL, 0xe6775d5dUL, 0xff6c6c1cUL,
+    0xd4413fdfUL, 0xcd5a0e9eUL, 0x958424a2UL, 0x8c9f15e3UL, 0xa7b24620UL,
+    0xbea97761UL, 0xf1e8e1a6UL, 0xe8f3d0e7UL, 0xc3de8324UL, 0xdac5b265UL,
+    0x5d5daeaaUL, 0x44469febUL, 0x6f6bcc28UL, 0x7670fd69UL, 0x39316baeUL,
+    0x202a5aefUL, 0x0b07092cUL, 0x121c386dUL, 0xdf4636f3UL, 0xc65d07b2UL,
+    0xed705471UL, 0xf46b6530UL, 0xbb2af3f7UL, 0xa231c2b6UL, 0x891c9175UL,
+    0x9007a034UL, 0x179fbcfbUL, 0x0e848dbaUL, 0x25a9de79UL, 0x3cb2ef38UL,
+    0x73f379ffUL, 0x6ae848beUL, 0x41c51b7dUL, 0x58de2a3cUL, 0xf0794f05UL,
+    0xe9627e44UL, 0xc24f2d87UL, 0xdb541cc6UL, 0x94158a01UL, 0x8d0ebb40UL,
+    0xa623e883UL, 0xbf38d9c2UL, 0x38a0c50dUL, 0x21bbf44cUL, 0x0a96a78fUL,
+    0x138d96ceUL, 0x5ccc0009UL, 0x45d73148UL, 0x6efa628bUL, 0x77e153caUL,
+    0xbabb5d54UL, 0xa3a06c15UL, 0x888d3fd6UL, 0x91960e97UL, 0xded79850UL,
+    0xc7cca911UL, 0xece1fad2UL, 0xf5facb93UL, 0x7262d75cUL, 0x6b79e61dUL,
+    0x4054b5deUL, 0x594f849fUL, 0x160e1258UL, 0x0f152319UL, 0x243870daUL,
+    0x3d23419bUL, 0x65fd6ba7UL, 0x7ce65ae6UL, 0x57cb0925UL, 0x4ed03864UL,
+    0x0191aea3UL, 0x188a9fe2UL, 0x33a7cc21UL, 0x2abcfd60UL, 0xad24e1afUL,
+    0xb43fd0eeUL, 0x9f12832dUL, 0x8609b26cUL, 0xc94824abUL, 0xd05315eaUL,
+    0xfb7e4629UL, 0xe2657768UL, 0x2f3f79f6UL, 0x362448b7UL, 0x1d091b74UL,
+    0x04122a35UL, 0x4b53bcf2UL, 0x52488db3UL, 0x7965de70UL, 0x607eef31UL,
+    0xe7e6f3feUL, 0xfefdc2bfUL, 0xd5d0917cUL, 0xcccba03dUL, 0x838a36faUL,
+    0x9a9107bbUL, 0xb1bc5478UL, 0xa8a76539UL, 0x3b83984bUL, 0x2298a90aUL,
+    0x09b5fac9UL, 0x10aecb88UL, 0x5fef5d4fUL, 0x46f46c0eUL, 0x6dd93fcdUL,
+    0x74c20e8cUL, 0xf35a1243UL, 0xea412302UL, 0xc16c70c1UL, 0xd8774180UL,
+    0x9736d747UL, 0x8e2de606UL, 0xa500b5c5UL, 0xbc1b8484UL, 0x71418a1aUL,
+    0x685abb5bUL, 0x4377e898UL, 0x5a6cd9d9UL, 0x152d4f1eUL, 0x0c367e5fUL,
+    0x271b2d9cUL, 0x3e001cddUL, 0xb9980012UL, 0xa0833153UL, 0x8bae6290UL,
+    0x92b553d1UL, 0xddf4c516UL, 0xc4eff457UL, 0xefc2a794UL, 0xf6d996d5UL,
+    0xae07bce9UL, 0xb71c8da8UL, 0x9c31de6bUL, 0x852aef2aUL, 0xca6b79edUL,
+    0xd37048acUL, 0xf85d1b6fUL, 0xe1462a2eUL, 0x66de36e1UL, 0x7fc507a0UL,
+    0x54e85463UL, 0x4df36522UL, 0x02b2f3e5UL, 0x1ba9c2a4UL, 0x30849167UL,
+    0x299fa026UL, 0xe4c5aeb8UL, 0xfdde9ff9UL, 0xd6f3cc3aUL, 0xcfe8fd7bUL,
+    0x80a96bbcUL, 0x99b25afdUL, 0xb29f093eUL, 0xab84387fUL, 0x2c1c24b0UL,
+    0x350715f1UL, 0x1e2a4632UL, 0x07317773UL, 0x4870e1b4UL, 0x516bd0f5UL,
+    0x7a468336UL, 0x635db277UL, 0xcbfad74eUL, 0xd2e1e60fUL, 0xf9ccb5ccUL,
+    0xe0d7848dUL, 0xaf96124aUL, 0xb68d230bUL, 0x9da070c8UL, 0x84bb4189UL,
+    0x03235d46UL, 0x1a386c07UL, 0x31153fc4UL, 0x280e0e85UL, 0x674f9842UL,
+    0x7e54a903UL, 0x5579fac0UL, 0x4c62cb81UL, 0x8138c51fUL, 0x9823f45eUL,
+    0xb30ea79dUL, 0xaa1596dcUL, 0xe554001bUL, 0xfc4f315aUL, 0xd7626299UL,
+    0xce7953d8UL, 0x49e14f17UL, 0x50fa7e56UL, 0x7bd72d95UL, 0x62cc1cd4UL,
+    0x2d8d8a13UL, 0x3496bb52UL, 0x1fbbe891UL, 0x06a0d9d0UL, 0x5e7ef3ecUL,
+    0x4765c2adUL, 0x6c48916eUL, 0x7553a02fUL, 0x3a1236e8UL, 0x230907a9UL,
+    0x0824546aUL, 0x113f652bUL, 0x96a779e4UL, 0x8fbc48a5UL, 0xa4911b66UL,
+    0xbd8a2a27UL, 0xf2cbbce0UL, 0xebd08da1UL, 0xc0fdde62UL, 0xd9e6ef23UL,
+    0x14bce1bdUL, 0x0da7d0fcUL, 0x268a833fUL, 0x3f91b27eUL, 0x70d024b9UL,
+    0x69cb15f8UL, 0x42e6463bUL, 0x5bfd777aUL, 0xdc656bb5UL, 0xc57e5af4UL,
+    0xee530937UL, 0xf7483876UL, 0xb809aeb1UL, 0xa1129ff0UL, 0x8a3fcc33UL,
+    0x9324fd72UL
+  },
+  {
+    0x00000000UL, 0x01c26a37UL, 0x0384d46eUL, 0x0246be59UL, 0x0709a8dcUL,
+    0x06cbc2ebUL, 0x048d7cb2UL, 0x054f1685UL, 0x0e1351b8UL, 0x0fd13b8fUL,
+    0x0d9785d6UL, 0x0c55efe1UL, 0x091af964UL, 0x08d89353UL, 0x0a9e2d0aUL,
+    0x0b5c473dUL, 0x1c26a370UL, 0x1de4c947UL, 0x1fa2771eUL, 0x1e601d29UL,
+    0x1b2f0bacUL, 0x1aed619bUL, 0x18abdfc2UL, 0x1969b5f5UL, 0x1235f2c8UL,
+    0x13f798ffUL, 0x11b126a6UL, 0x10734c91UL, 0x153c5a14UL, 0x14fe3023UL,
+    0x16b88e7aUL, 0x177ae44dUL, 0x384d46e0UL, 0x398f2cd7UL, 0x3bc9928eUL,
+    0x3a0bf8b9UL, 0x3f44ee3cUL, 0x3e86840bUL, 0x3cc03a52UL, 0x3d025065UL,
+    0x365e1758UL, 0x379c7d6fUL, 0x35dac336UL, 0x3418a901UL, 0x3157bf84UL,
+    0x3095d5b3UL, 0x32d36beaUL, 0x331101ddUL, 0x246be590UL, 0x25a98fa7UL,
+    0x27ef31feUL, 0x262d5bc9UL, 0x23624d4cUL, 0x22a0277bUL, 0x20e69922UL,
+    0x2124f315UL, 0x2a78b428UL, 0x2bbade1fUL, 0x29fc6046UL, 0x283e0a71UL,
+    0x2d711cf4UL, 0x2cb376c3UL, 0x2ef5c89aUL, 0x2f37a2adUL, 0x709a8dc0UL,
+    0x7158e7f7UL, 0x731e59aeUL, 0x72dc3399UL, 0x7793251cUL, 0x76514f2bUL,
+    0x7417f172UL, 0x75d59b45UL, 0x7e89dc78UL, 0x7f4bb64fUL, 0x7d0d0816UL,
+    0x7ccf6221UL, 0x798074a4UL, 0x78421e93UL, 0x7a04a0caUL, 0x7bc6cafdUL,
+    0x6cbc2eb0UL, 0x6d7e4487UL, 0x6f38fadeUL, 0x6efa90e9UL, 0x6bb5866cUL,
+    0x6a77ec5bUL, 0x68315202UL, 0x69f33835UL, 0x62af7f08UL, 0x636d153fUL,
+    0x612bab66UL, 0x60e9c151UL, 0x65a6d7d4UL, 0x6464bde3UL, 0x662203baUL,
+    0x67e0698dUL, 0x48d7cb20UL, 0x4915a117UL, 0x4b531f4eUL, 0x4a917579UL,
+    0x4fde63fcUL, 0x4e1c09cbUL, 0x4c5ab792UL, 0x4d98dda5UL, 0x46c49a98UL,
+    0x4706f0afUL, 0x45404ef6UL, 0x448224c1UL, 0x41cd3244UL, 0x400f5873UL,
+    0x4249e62aUL, 0x438b8c1dUL, 0x54f16850UL, 0x55330267UL, 0x5775bc3eUL,
+    0x56b7d609UL, 0x53f8c08cUL, 0x523aaabbUL, 0x507c14e2UL, 0x51be7ed5UL,
+    0x5ae239e8UL, 0x5b2053dfUL, 0x5966ed86UL, 0x58a487b1UL, 0x5deb9134UL,
+    0x5c29fb03UL, 0x5e6f455aUL, 0x5fad2f6dUL, 0xe1351b80UL, 0xe0f771b7UL,
+    0xe2b1cfeeUL, 0xe373a5d9UL, 0xe63cb35cUL, 0xe7fed96bUL, 0xe5b86732UL,
+    0xe47a0d05UL, 0xef264a38UL, 0xeee4200fUL, 0xeca29e56UL, 0xed60f461UL,
+    0xe82fe2e4UL, 0xe9ed88d3UL, 0xebab368aUL, 0xea695cbdUL, 0xfd13b8f0UL,
+    0xfcd1d2c7UL, 0xfe976c9eUL, 0xff5506a9UL, 0xfa1a102cUL, 0xfbd87a1bUL,
+    0xf99ec442UL, 0xf85cae75UL, 0xf300e948UL, 0xf2c2837fUL, 0xf0843d26UL,
+    0xf1465711UL, 0xf4094194UL, 0xf5cb2ba3UL, 0xf78d95faUL, 0xf64fffcdUL,
+    0xd9785d60UL, 0xd8ba3757UL, 0xdafc890eUL, 0xdb3ee339UL, 0xde71f5bcUL,
+    0xdfb39f8bUL, 0xddf521d2UL, 0xdc374be5UL, 0xd76b0cd8UL, 0xd6a966efUL,
+    0xd4efd8b6UL, 0xd52db281UL, 0xd062a404UL, 0xd1a0ce33UL, 0xd3e6706aUL,
+    0xd2241a5dUL, 0xc55efe10UL, 0xc49c9427UL, 0xc6da2a7eUL, 0xc7184049UL,
+    0xc25756ccUL, 0xc3953cfbUL, 0xc1d382a2UL, 0xc011e895UL, 0xcb4dafa8UL,
+    0xca8fc59fUL, 0xc8c97bc6UL, 0xc90b11f1UL, 0xcc440774UL, 0xcd866d43UL,
+    0xcfc0d31aUL, 0xce02b92dUL, 0x91af9640UL, 0x906dfc77UL, 0x922b422eUL,
+    0x93e92819UL, 0x96a63e9cUL, 0x976454abUL, 0x9522eaf2UL, 0x94e080c5UL,
+    0x9fbcc7f8UL, 0x9e7eadcfUL, 0x9c381396UL, 0x9dfa79a1UL, 0x98b56f24UL,
+    0x99770513UL, 0x9b31bb4aUL, 0x9af3d17dUL, 0x8d893530UL, 0x8c4b5f07UL,
+    0x8e0de15eUL, 0x8fcf8b69UL, 0x8a809decUL, 0x8b42f7dbUL, 0x89044982UL,
+    0x88c623b5UL, 0x839a6488UL, 0x82580ebfUL, 0x801eb0e6UL, 0x81dcdad1UL,
+    0x8493cc54UL, 0x8551a663UL, 0x8717183aUL, 0x86d5720dUL, 0xa9e2d0a0UL,
+    0xa820ba97UL, 0xaa6604ceUL, 0xaba46ef9UL, 0xaeeb787cUL, 0xaf29124bUL,
+    0xad6fac12UL, 0xacadc625UL, 0xa7f18118UL, 0xa633eb2fUL, 0xa4755576UL,
+    0xa5b73f41UL, 0xa0f829c4UL, 0xa13a43f3UL, 0xa37cfdaaUL, 0xa2be979dUL,
+    0xb5c473d0UL, 0xb40619e7UL, 0xb640a7beUL, 0xb782cd89UL, 0xb2cddb0cUL,
+    0xb30fb13bUL, 0xb1490f62UL, 0xb08b6555UL, 0xbbd72268UL, 0xba15485fUL,
+    0xb853f606UL, 0xb9919c31UL, 0xbcde8ab4UL, 0xbd1ce083UL, 0xbf5a5edaUL,
+    0xbe9834edUL
+  },
+  {
+    0x00000000UL, 0xb8bc6765UL, 0xaa09c88bUL, 0x12b5afeeUL, 0x8f629757UL,
+    0x37def032UL, 0x256b5fdcUL, 0x9dd738b9UL, 0xc5b428efUL, 0x7d084f8aUL,
+    0x6fbde064UL, 0xd7018701UL, 0x4ad6bfb8UL, 0xf26ad8ddUL, 0xe0df7733UL,
+    0x58631056UL, 0x5019579fUL, 0xe8a530faUL, 0xfa109f14UL, 0x42acf871UL,
+    0xdf7bc0c8UL, 0x67c7a7adUL, 0x75720843UL, 0xcdce6f26UL, 0x95ad7f70UL,
+    0x2d111815UL, 0x3fa4b7fbUL, 0x8718d09eUL, 0x1acfe827UL, 0xa2738f42UL,
+    0xb0c620acUL, 0x087a47c9UL, 0xa032af3eUL, 0x188ec85bUL, 0x0a3b67b5UL,
+    0xb28700d0UL, 0x2f503869UL, 0x97ec5f0cUL, 0x8559f0e2UL, 0x3de59787UL,
+    0x658687d1UL, 0xdd3ae0b4UL, 0xcf8f4f5aUL, 0x7733283fUL, 0xeae41086UL,
+    0x525877e3UL, 0x40edd80dUL, 0xf851bf68UL, 0xf02bf8a1UL, 0x48979fc4UL,
+    0x5a22302aUL, 0xe29e574fUL, 0x7f496ff6UL, 0xc7f50893UL, 0xd540a77dUL,
+    0x6dfcc018UL, 0x359fd04eUL, 0x8d23b72bUL, 0x9f9618c5UL, 0x272a7fa0UL,
+    0xbafd4719UL, 0x0241207cUL, 0x10f48f92UL, 0xa848e8f7UL, 0x9b14583dUL,
+    0x23a83f58UL, 0x311d90b6UL, 0x89a1f7d3UL, 0x1476cf6aUL, 0xaccaa80fUL,
+    0xbe7f07e1UL, 0x06c36084UL, 0x5ea070d2UL, 0xe61c17b7UL, 0xf4a9b859UL,
+    0x4c15df3cUL, 0xd1c2e785UL, 0x697e80e0UL, 0x7bcb2f0eUL, 0xc377486bUL,
+    0xcb0d0fa2UL, 0x73b168c7UL, 0x6104c729UL, 0xd9b8a04cUL, 0x446f98f5UL,
+    0xfcd3ff90UL, 0xee66507eUL, 0x56da371bUL, 0x0eb9274dUL, 0xb6054028UL,
+    0xa4b0efc6UL, 0x1c0c88a3UL, 0x81dbb01aUL, 0x3967d77fUL, 0x2bd27891UL,
+    0x936e1ff4UL, 0x3b26f703UL, 0x839a9066UL, 0x912f3f88UL, 0x299358edUL,
+    0xb4446054UL, 0x0cf80731UL, 0x1e4da8dfUL, 0xa6f1cfbaUL, 0xfe92dfecUL,
+    0x462eb889UL, 0x549b1767UL, 0xec277002UL, 0x71f048bbUL, 0xc94c2fdeUL,
+    0xdbf98030UL, 0x6345e755UL, 0x6b3fa09cUL, 0xd383c7f9UL, 0xc1366817UL,
+    0x798a0f72UL, 0xe45d37cbUL, 0x5ce150aeUL, 0x4e54ff40UL, 0xf6e89825UL,
+    0xae8b8873UL, 0x1637ef16UL, 0x048240f8UL, 0xbc3e279dUL, 0x21e91f24UL,
+    0x99557841UL, 0x8be0d7afUL, 0x335cb0caUL, 0xed59b63bUL, 0x55e5d15eUL,
+    0x47507eb0UL, 0xffec19d5UL, 0x623b216cUL, 0xda874609UL, 0xc832e9e7UL,
+    0x708e8e82UL, 0x28ed9ed4UL, 0x9051f9b1UL, 0x82e4565fUL, 0x3a58313aUL,
+    0xa78f0983UL, 0x1f336ee6UL, 0x0d86c108UL, 0xb53aa66dUL, 0xbd40e1a4UL,
+    0x05fc86c1UL, 0x1749292fUL, 0xaff54e4aUL, 0x322276f3UL, 0x8a9e1196UL,
+    0x982bbe78UL, 0x2097d91dUL, 0x78f4c94bUL, 0xc048ae2eUL, 0xd2fd01c0UL,
+    0x6a4166a5UL, 0xf7965e1cUL, 0x4f2a3979UL, 0x5d9f9697UL, 0xe523f1f2UL,
+    0x4d6b1905UL, 0xf5d77e60UL, 0xe762d18eUL, 0x5fdeb6ebUL, 0xc2098e52UL,
+    0x7ab5e937UL, 0x680046d9UL, 0xd0bc21bcUL, 0x88df31eaUL, 0x3063568fUL,
+    0x22d6f961UL, 0x9a6a9e04UL, 0x07bda6bdUL, 0xbf01c1d8UL, 0xadb46e36UL,
+    0x15080953UL, 0x1d724e9aUL, 0xa5ce29ffUL, 0xb77b8611UL, 0x0fc7e174UL,
+    0x9210d9cdUL, 0x2aacbea8UL, 0x38191146UL, 0x80a57623UL, 0xd8c66675UL,
+    0x607a0110UL, 0x72cfaefeUL, 0xca73c99bUL, 0x57a4f122UL, 0xef189647UL,
+    0xfdad39a9UL, 0x45115eccUL, 0x764dee06UL, 0xcef18963UL, 0xdc44268dUL,
+    0x64f841e8UL, 0xf92f7951UL, 0x41931e34UL, 0x5326b1daUL, 0xeb9ad6bfUL,
+    0xb3f9c6e9UL, 0x0b45a18cUL, 0x19f00e62UL, 0xa14c6907UL, 0x3c9b51beUL,
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+    0xb1b8e695UL, 0xa30d497bUL, 0x1bb12e1eUL, 0x43d23e48UL, 0xfb6e592dUL,
+    0xe9dbf6c3UL, 0x516791a6UL, 0xccb0a91fUL, 0x740cce7aUL, 0x66b96194UL,
+    0xde0506f1UL
+  },
+  {
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+    0x021b685dUL, 0x942b6f2aUL, 0x37be0bb4UL, 0xa18e0cc3UL, 0x1bdf055aUL,
+    0x8def022dUL
+  },
+  {
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+    0x370953eeUL, 0x763848f7UL, 0xb1ae09b8UL, 0xf09f12a1UL, 0x33cc3f8aUL,
+    0x72fd2493UL
+  },
+  {
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+    0xebc2cb06UL, 0xb27c8d04UL, 0x85164f05UL, 0xb851130eUL, 0x8f3bd10fUL,
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+    0x2162cf7cUL, 0xa4748079UL, 0x931e4278UL, 0xcaa0047aUL, 0xfdcac67bUL,
+    0xb02ebc6cUL, 0x87447e6dUL, 0xdefa386fUL, 0xe990fa6eUL, 0x6c86b56bUL,
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+    0xfc63de4fUL, 0xcb091c4eUL, 0x92b75a4cUL, 0xa5dd984dUL, 0x989ac446UL,
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+    0x8b9fb3dfUL, 0xd221f5ddUL, 0xe54b37dcUL, 0xd80c6bd7UL, 0xef66a9d6UL,
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+    0xcc5657c2UL, 0xfb3c95c3UL, 0xa282d3c1UL, 0x95e811c0UL, 0xa8af4dcbUL,
+    0x9fc58fcaUL, 0xc67bc9c8UL, 0xf1110bc9UL, 0x740744ccUL, 0x436d86cdUL,
+    0x1ad3c0cfUL, 0x2db902ceUL, 0x4096af91UL, 0x77fc6d90UL, 0x2e422b92UL,
+    0x1928e993UL, 0x9c3ea696UL, 0xab546497UL, 0xf2ea2295UL, 0xc580e094UL,
+    0xf8c7bc9fUL, 0xcfad7e9eUL, 0x9613389cUL, 0xa179fa9dUL, 0x246fb598UL,
+    0x13057799UL, 0x4abb319bUL, 0x7dd1f39aUL, 0x3035898dUL, 0x075f4b8cUL,
+    0x5ee10d8eUL, 0x698bcf8fUL, 0xec9d808aUL, 0xdbf7428bUL, 0x82490489UL,
+    0xb523c688UL, 0x88649a83UL, 0xbf0e5882UL, 0xe6b01e80UL, 0xd1dadc81UL,
+    0x54cc9384UL, 0x63a65185UL, 0x3a181787UL, 0x0d72d586UL, 0xa0d0e2a9UL,
+    0x97ba20a8UL, 0xce0466aaUL, 0xf96ea4abUL, 0x7c78ebaeUL, 0x4b1229afUL,
+    0x12ac6fadUL, 0x25c6adacUL, 0x1881f1a7UL, 0x2feb33a6UL, 0x765575a4UL,
+    0x413fb7a5UL, 0xc429f8a0UL, 0xf3433aa1UL, 0xaafd7ca3UL, 0x9d97bea2UL,
+    0xd073c4b5UL, 0xe71906b4UL, 0xbea740b6UL, 0x89cd82b7UL, 0x0cdbcdb2UL,
+    0x3bb10fb3UL, 0x620f49b1UL, 0x55658bb0UL, 0x6822d7bbUL, 0x5f4815baUL,
+    0x06f653b8UL, 0x319c91b9UL, 0xb48adebcUL, 0x83e01cbdUL, 0xda5e5abfUL,
+    0xed3498beUL
+  },
+  {
+    0x00000000UL, 0x6567bcb8UL, 0x8bc809aaUL, 0xeeafb512UL, 0x5797628fUL,
+    0x32f0de37UL, 0xdc5f6b25UL, 0xb938d79dUL, 0xef28b4c5UL, 0x8a4f087dUL,
+    0x64e0bd6fUL, 0x018701d7UL, 0xb8bfd64aUL, 0xddd86af2UL, 0x3377dfe0UL,
+    0x56106358UL, 0x9f571950UL, 0xfa30a5e8UL, 0x149f10faUL, 0x71f8ac42UL,
+    0xc8c07bdfUL, 0xada7c767UL, 0x43087275UL, 0x266fcecdUL, 0x707fad95UL,
+    0x1518112dUL, 0xfbb7a43fUL, 0x9ed01887UL, 0x27e8cf1aUL, 0x428f73a2UL,
+    0xac20c6b0UL, 0xc9477a08UL, 0x3eaf32a0UL, 0x5bc88e18UL, 0xb5673b0aUL,
+    0xd00087b2UL, 0x6938502fUL, 0x0c5fec97UL, 0xe2f05985UL, 0x8797e53dUL,
+    0xd1878665UL, 0xb4e03addUL, 0x5a4f8fcfUL, 0x3f283377UL, 0x8610e4eaUL,
+    0xe3775852UL, 0x0dd8ed40UL, 0x68bf51f8UL, 0xa1f82bf0UL, 0xc49f9748UL,
+    0x2a30225aUL, 0x4f579ee2UL, 0xf66f497fUL, 0x9308f5c7UL, 0x7da740d5UL,
+    0x18c0fc6dUL, 0x4ed09f35UL, 0x2bb7238dUL, 0xc518969fUL, 0xa07f2a27UL,
+    0x1947fdbaUL, 0x7c204102UL, 0x928ff410UL, 0xf7e848a8UL, 0x3d58149bUL,
+    0x583fa823UL, 0xb6901d31UL, 0xd3f7a189UL, 0x6acf7614UL, 0x0fa8caacUL,
+    0xe1077fbeUL, 0x8460c306UL, 0xd270a05eUL, 0xb7171ce6UL, 0x59b8a9f4UL,
+    0x3cdf154cUL, 0x85e7c2d1UL, 0xe0807e69UL, 0x0e2fcb7bUL, 0x6b4877c3UL,
+    0xa20f0dcbUL, 0xc768b173UL, 0x29c70461UL, 0x4ca0b8d9UL, 0xf5986f44UL,
+    0x90ffd3fcUL, 0x7e5066eeUL, 0x1b37da56UL, 0x4d27b90eUL, 0x284005b6UL,
+    0xc6efb0a4UL, 0xa3880c1cUL, 0x1ab0db81UL, 0x7fd76739UL, 0x9178d22bUL,
+    0xf41f6e93UL, 0x03f7263bUL, 0x66909a83UL, 0x883f2f91UL, 0xed589329UL,
+    0x546044b4UL, 0x3107f80cUL, 0xdfa84d1eUL, 0xbacff1a6UL, 0xecdf92feUL,
+    0x89b82e46UL, 0x67179b54UL, 0x027027ecUL, 0xbb48f071UL, 0xde2f4cc9UL,
+    0x3080f9dbUL, 0x55e74563UL, 0x9ca03f6bUL, 0xf9c783d3UL, 0x176836c1UL,
+    0x720f8a79UL, 0xcb375de4UL, 0xae50e15cUL, 0x40ff544eUL, 0x2598e8f6UL,
+    0x73888baeUL, 0x16ef3716UL, 0xf8408204UL, 0x9d273ebcUL, 0x241fe921UL,
+    0x41785599UL, 0xafd7e08bUL, 0xcab05c33UL, 0x3bb659edUL, 0x5ed1e555UL,
+    0xb07e5047UL, 0xd519ecffUL, 0x6c213b62UL, 0x094687daUL, 0xe7e932c8UL,
+    0x828e8e70UL, 0xd49eed28UL, 0xb1f95190UL, 0x5f56e482UL, 0x3a31583aUL,
+    0x83098fa7UL, 0xe66e331fUL, 0x08c1860dUL, 0x6da63ab5UL, 0xa4e140bdUL,
+    0xc186fc05UL, 0x2f294917UL, 0x4a4ef5afUL, 0xf3762232UL, 0x96119e8aUL,
+    0x78be2b98UL, 0x1dd99720UL, 0x4bc9f478UL, 0x2eae48c0UL, 0xc001fdd2UL,
+    0xa566416aUL, 0x1c5e96f7UL, 0x79392a4fUL, 0x97969f5dUL, 0xf2f123e5UL,
+    0x05196b4dUL, 0x607ed7f5UL, 0x8ed162e7UL, 0xebb6de5fUL, 0x528e09c2UL,
+    0x37e9b57aUL, 0xd9460068UL, 0xbc21bcd0UL, 0xea31df88UL, 0x8f566330UL,
+    0x61f9d622UL, 0x049e6a9aUL, 0xbda6bd07UL, 0xd8c101bfUL, 0x366eb4adUL,
+    0x53090815UL, 0x9a4e721dUL, 0xff29cea5UL, 0x11867bb7UL, 0x74e1c70fUL,
+    0xcdd91092UL, 0xa8beac2aUL, 0x46111938UL, 0x2376a580UL, 0x7566c6d8UL,
+    0x10017a60UL, 0xfeaecf72UL, 0x9bc973caUL, 0x22f1a457UL, 0x479618efUL,
+    0xa939adfdUL, 0xcc5e1145UL, 0x06ee4d76UL, 0x6389f1ceUL, 0x8d2644dcUL,
+    0xe841f864UL, 0x51792ff9UL, 0x341e9341UL, 0xdab12653UL, 0xbfd69aebUL,
+    0xe9c6f9b3UL, 0x8ca1450bUL, 0x620ef019UL, 0x07694ca1UL, 0xbe519b3cUL,
+    0xdb362784UL, 0x35999296UL, 0x50fe2e2eUL, 0x99b95426UL, 0xfcdee89eUL,
+    0x12715d8cUL, 0x7716e134UL, 0xce2e36a9UL, 0xab498a11UL, 0x45e63f03UL,
+    0x208183bbUL, 0x7691e0e3UL, 0x13f65c5bUL, 0xfd59e949UL, 0x983e55f1UL,
+    0x2106826cUL, 0x44613ed4UL, 0xaace8bc6UL, 0xcfa9377eUL, 0x38417fd6UL,
+    0x5d26c36eUL, 0xb389767cUL, 0xd6eecac4UL, 0x6fd61d59UL, 0x0ab1a1e1UL,
+    0xe41e14f3UL, 0x8179a84bUL, 0xd769cb13UL, 0xb20e77abUL, 0x5ca1c2b9UL,
+    0x39c67e01UL, 0x80fea99cUL, 0xe5991524UL, 0x0b36a036UL, 0x6e511c8eUL,
+    0xa7166686UL, 0xc271da3eUL, 0x2cde6f2cUL, 0x49b9d394UL, 0xf0810409UL,
+    0x95e6b8b1UL, 0x7b490da3UL, 0x1e2eb11bUL, 0x483ed243UL, 0x2d596efbUL,
+    0xc3f6dbe9UL, 0xa6916751UL, 0x1fa9b0ccUL, 0x7ace0c74UL, 0x9461b966UL,
+    0xf10605deUL
+#endif
+  }
+};
diff --git a/gs/zlib/deflate.c b/gs/zlib/deflate.c
new file mode 100644
index 000000000..29ce1f64a
--- /dev/null
+++ b/gs/zlib/deflate.c
@@ -0,0 +1,1736 @@
+/* deflate.c -- compress data using the deflation algorithm
+ * Copyright (C) 1995-2005 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/*
+ *  ALGORITHM
+ *
+ *      The "deflation" process depends on being able to identify portions
+ *      of the input text which are identical to earlier input (within a
+ *      sliding window trailing behind the input currently being processed).
+ *
+ *      The most straightforward technique turns out to be the fastest for
+ *      most input files: try all possible matches and select the longest.
+ *      The key feature of this algorithm is that insertions into the string
+ *      dictionary are very simple and thus fast, and deletions are avoided
+ *      completely. Insertions are performed at each input character, whereas
+ *      string matches are performed only when the previous match ends. So it
+ *      is preferable to spend more time in matches to allow very fast string
+ *      insertions and avoid deletions. The matching algorithm for small
+ *      strings is inspired from that of Rabin & Karp. A brute force approach
+ *      is used to find longer strings when a small match has been found.
+ *      A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
+ *      (by Leonid Broukhis).
+ *         A previous version of this file used a more sophisticated algorithm
+ *      (by Fiala and Greene) which is guaranteed to run in linear amortized
+ *      time, but has a larger average cost, uses more memory and is patented.
+ *      However the F&G algorithm may be faster for some highly redundant
+ *      files if the parameter max_chain_length (described below) is too large.
+ *
+ *  ACKNOWLEDGEMENTS
+ *
+ *      The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
+ *      I found it in 'freeze' written by Leonid Broukhis.
+ *      Thanks to many people for bug reports and testing.
+ *
+ *  REFERENCES
+ *
+ *      Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
+ *      Available in http://www.ietf.org/rfc/rfc1951.txt
+ *
+ *      A description of the Rabin and Karp algorithm is given in the book
+ *         "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
+ *
+ *      Fiala,E.R., and Greene,D.H.
+ *         Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
+ *
+ */
+
+/* @(#) $Id$ */
+
+#include "deflate.h"
+
+const char deflate_copyright[] =
+   " deflate 1.2.3 Copyright 1995-2005 Jean-loup Gailly ";
+/*
+  If you use the zlib library in a product, an acknowledgment is welcome
+  in the documentation of your product. If for some reason you cannot
+  include such an acknowledgment, I would appreciate that you keep this
+  copyright string in the executable of your product.
+ */
+
+/* ===========================================================================
+ *  Function prototypes.
+ */
+typedef enum {
+    need_more,      /* block not completed, need more input or more output */
+    block_done,     /* block flush performed */
+    finish_started, /* finish started, need only more output at next deflate */
+    finish_done     /* finish done, accept no more input or output */
+} block_state;
+
+typedef block_state (*compress_func) OF((deflate_state *s, int flush));
+/* Compression function. Returns the block state after the call. */
+
+local void fill_window    OF((deflate_state *s));
+local block_state deflate_stored OF((deflate_state *s, int flush));
+local block_state deflate_fast   OF((deflate_state *s, int flush));
+#ifndef FASTEST
+local block_state deflate_slow   OF((deflate_state *s, int flush));
+#endif
+local void lm_init        OF((deflate_state *s));
+local void putShortMSB    OF((deflate_state *s, uInt b));
+local void flush_pending  OF((z_streamp strm));
+local int read_buf        OF((z_streamp strm, Bytef *buf, unsigned size));
+#ifndef FASTEST
+#ifdef ASMV
+      void match_init OF((void)); /* asm code initialization */
+      uInt longest_match  OF((deflate_state *s, IPos cur_match));
+#else
+local uInt longest_match  OF((deflate_state *s, IPos cur_match));
+#endif
+#endif
+local uInt longest_match_fast OF((deflate_state *s, IPos cur_match));
+
+#ifdef DEBUG
+local  void check_match OF((deflate_state *s, IPos start, IPos match,
+                            int length));
+#endif
+
+/* ===========================================================================
+ * Local data
+ */
+
+#define NIL 0
+/* Tail of hash chains */
+
+#ifndef TOO_FAR
+#  define TOO_FAR 4096
+#endif
+/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
+
+#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
+/* Minimum amount of lookahead, except at the end of the input file.
+ * See deflate.c for comments about the MIN_MATCH+1.
+ */
+
+/* Values for max_lazy_match, good_match and max_chain_length, depending on
+ * the desired pack level (0..9). The values given below have been tuned to
+ * exclude worst case performance for pathological files. Better values may be
+ * found for specific files.
+ */
+typedef struct config_s {
+   ush good_length; /* reduce lazy search above this match length */
+   ush max_lazy;    /* do not perform lazy search above this match length */
+   ush nice_length; /* quit search above this match length */
+   ush max_chain;
+   compress_func func;
+} config;
+
+#ifdef FASTEST
+local const config configuration_table[2] = {
+/*      good lazy nice chain */
+/* 0 */ {0,    0,  0,    0, deflate_stored},  /* store only */
+/* 1 */ {4,    4,  8,    4, deflate_fast}}; /* max speed, no lazy matches */
+#else
+local const config configuration_table[10] = {
+/*      good lazy nice chain */
+/* 0 */ {0,    0,  0,    0, deflate_stored},  /* store only */
+/* 1 */ {4,    4,  8,    4, deflate_fast}, /* max speed, no lazy matches */
+/* 2 */ {4,    5, 16,    8, deflate_fast},
+/* 3 */ {4,    6, 32,   32, deflate_fast},
+
+/* 4 */ {4,    4, 16,   16, deflate_slow},  /* lazy matches */
+/* 5 */ {8,   16, 32,   32, deflate_slow},
+/* 6 */ {8,   16, 128, 128, deflate_slow},
+/* 7 */ {8,   32, 128, 256, deflate_slow},
+/* 8 */ {32, 128, 258, 1024, deflate_slow},
+/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* max compression */
+#endif
+
+/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
+ * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
+ * meaning.
+ */
+
+#define EQUAL 0
+/* result of memcmp for equal strings */
+
+#ifndef NO_DUMMY_DECL
+struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
+#endif
+
+/* ===========================================================================
+ * Update a hash value with the given input byte
+ * IN  assertion: all calls to to UPDATE_HASH are made with consecutive
+ *    input characters, so that a running hash key can be computed from the
+ *    previous key instead of complete recalculation each time.
+ */
+#define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
+
+
+/* ===========================================================================
+ * Insert string str in the dictionary and set match_head to the previous head
+ * of the hash chain (the most recent string with same hash key). Return
+ * the previous length of the hash chain.
+ * If this file is compiled with -DFASTEST, the compression level is forced
+ * to 1, and no hash chains are maintained.
+ * IN  assertion: all calls to to INSERT_STRING are made with consecutive
+ *    input characters and the first MIN_MATCH bytes of str are valid
+ *    (except for the last MIN_MATCH-1 bytes of the input file).
+ */
+#ifdef FASTEST
+#define INSERT_STRING(s, str, match_head) \
+   (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
+    match_head = s->head[s->ins_h], \
+    s->head[s->ins_h] = (Pos)(str))
+#else
+#define INSERT_STRING(s, str, match_head) \
+   (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
+    match_head = s->prev[(str) & s->w_mask] = s->head[s->ins_h], \
+    s->head[s->ins_h] = (Pos)(str))
+#endif
+
+/* ===========================================================================
+ * Initialize the hash table (avoiding 64K overflow for 16 bit systems).
+ * prev[] will be initialized on the fly.
+ */
+#define CLEAR_HASH(s) \
+    s->head[s->hash_size-1] = NIL; \
+    zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
+
+/* ========================================================================= */
+int ZEXPORT deflateInit_(strm, level, version, stream_size)
+    z_streamp strm;
+    int level;
+    const char *version;
+    int stream_size;
+{
+    return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
+                         Z_DEFAULT_STRATEGY, version, stream_size);
+    /* To do: ignore strm->next_in if we use it as window */
+}
+
+/* ========================================================================= */
+int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
+                  version, stream_size)
+    z_streamp strm;
+    int  level;
+    int  method;
+    int  windowBits;
+    int  memLevel;
+    int  strategy;
+    const char *version;
+    int stream_size;
+{
+    deflate_state *s;
+    int wrap = 1;
+    static const char my_version[] = ZLIB_VERSION;
+
+    ushf *overlay;
+    /* We overlay pending_buf and d_buf+l_buf. This works since the average
+     * output size for (length,distance) codes is <= 24 bits.
+     */
+
+    if (version == Z_NULL || version[0] != my_version[0] ||
+        stream_size != sizeof(z_stream)) {
+        return Z_VERSION_ERROR;
+    }
+    if (strm == Z_NULL) return Z_STREAM_ERROR;
+
+    strm->msg = Z_NULL;
+    if (strm->zalloc == (alloc_func)0) {
+        strm->zalloc = zcalloc;
+        strm->opaque = (voidpf)0;
+    }
+    if (strm->zfree == (free_func)0) strm->zfree = zcfree;
+
+#ifdef FASTEST
+    if (level != 0) level = 1;
+#else
+    if (level == Z_DEFAULT_COMPRESSION) level = 6;
+#endif
+
+    if (windowBits < 0) { /* suppress zlib wrapper */
+        wrap = 0;
+        windowBits = -windowBits;
+    }
+#ifdef GZIP
+    else if (windowBits > 15) {
+        wrap = 2;       /* write gzip wrapper instead */
+        windowBits -= 16;
+    }
+#endif
+    if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
+        windowBits < 8 || windowBits > 15 || level < 0 || level > 9 ||
+        strategy < 0 || strategy > Z_FIXED) {
+        return Z_STREAM_ERROR;
+    }
+    if (windowBits == 8) windowBits = 9;  /* until 256-byte window bug fixed */
+    s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
+    if (s == Z_NULL) return Z_MEM_ERROR;
+    strm->state = (struct internal_state FAR *)s;
+    s->strm = strm;
+
+    s->wrap = wrap;
+    s->gzhead = Z_NULL;
+    s->w_bits = windowBits;
+    s->w_size = 1 << s->w_bits;
+    s->w_mask = s->w_size - 1;
+
+    s->hash_bits = memLevel + 7;
+    s->hash_size = 1 << s->hash_bits;
+    s->hash_mask = s->hash_size - 1;
+    s->hash_shift =  ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
+
+    s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
+    s->prev   = (Posf *)  ZALLOC(strm, s->w_size, sizeof(Pos));
+    s->head   = (Posf *)  ZALLOC(strm, s->hash_size, sizeof(Pos));
+
+    s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
+
+    overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
+    s->pending_buf = (uchf *) overlay;
+    s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
+
+    if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
+        s->pending_buf == Z_NULL) {
+        s->status = FINISH_STATE;
+        strm->msg = (char*)ERR_MSG(Z_MEM_ERROR);
+        deflateEnd (strm);
+        return Z_MEM_ERROR;
+    }
+    s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
+    s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
+
+    s->level = level;
+    s->strategy = strategy;
+    s->method = (Byte)method;
+
+    return deflateReset(strm);
+}
+
+/* ========================================================================= */
+int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
+    z_streamp strm;
+    const Bytef *dictionary;
+    uInt  dictLength;
+{
+    deflate_state *s;
+    uInt length = dictLength;
+    uInt n;
+    IPos hash_head = 0;
+
+    if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL ||
+        strm->state->wrap == 2 ||
+        (strm->state->wrap == 1 && strm->state->status != INIT_STATE))
+        return Z_STREAM_ERROR;
+
+    s = strm->state;
+    if (s->wrap)
+        strm->adler = adler32(strm->adler, dictionary, dictLength);
+
+    if (length < MIN_MATCH) return Z_OK;
+    if (length > MAX_DIST(s)) {
+        length = MAX_DIST(s);
+        dictionary += dictLength - length; /* use the tail of the dictionary */
+    }
+    zmemcpy(s->window, dictionary, length);
+    s->strstart = length;
+    s->block_start = (long)length;
+
+    /* Insert all strings in the hash table (except for the last two bytes).
+     * s->lookahead stays null, so s->ins_h will be recomputed at the next
+     * call of fill_window.
+     */
+    s->ins_h = s->window[0];
+    UPDATE_HASH(s, s->ins_h, s->window[1]);
+    for (n = 0; n <= length - MIN_MATCH; n++) {
+        INSERT_STRING(s, n, hash_head);
+    }
+    if (hash_head) hash_head = 0;  /* to make compiler happy */
+    return Z_OK;
+}
+
+/* ========================================================================= */
+int ZEXPORT deflateReset (strm)
+    z_streamp strm;
+{
+    deflate_state *s;
+
+    if (strm == Z_NULL || strm->state == Z_NULL ||
+        strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0) {
+        return Z_STREAM_ERROR;
+    }
+
+    strm->total_in = strm->total_out = 0;
+    strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
+    strm->data_type = Z_UNKNOWN;
+
+    s = (deflate_state *)strm->state;
+    s->pending = 0;
+    s->pending_out = s->pending_buf;
+
+    if (s->wrap < 0) {
+        s->wrap = -s->wrap; /* was made negative by deflate(..., Z_FINISH); */
+    }
+    s->status = s->wrap ? INIT_STATE : BUSY_STATE;
+    strm->adler =
+#ifdef GZIP
+        s->wrap == 2 ? crc32(0L, Z_NULL, 0) :
+#endif
+        adler32(0L, Z_NULL, 0);
+    s->last_flush = Z_NO_FLUSH;
+
+    _tr_init(s);
+    lm_init(s);
+
+    return Z_OK;
+}
+
+/* ========================================================================= */
+int ZEXPORT deflateSetHeader (strm, head)
+    z_streamp strm;
+    gz_headerp head;
+{
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    if (strm->state->wrap != 2) return Z_STREAM_ERROR;
+    strm->state->gzhead = head;
+    return Z_OK;
+}
+
+/* ========================================================================= */
+int ZEXPORT deflatePrime (strm, bits, value)
+    z_streamp strm;
+    int bits;
+    int value;
+{
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    strm->state->bi_valid = bits;
+    strm->state->bi_buf = (ush)(value & ((1 << bits) - 1));
+    return Z_OK;
+}
+
+/* ========================================================================= */
+int ZEXPORT deflateParams(strm, level, strategy)
+    z_streamp strm;
+    int level;
+    int strategy;
+{
+    deflate_state *s;
+    compress_func func;
+    int err = Z_OK;
+
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    s = strm->state;
+
+#ifdef FASTEST
+    if (level != 0) level = 1;
+#else
+    if (level == Z_DEFAULT_COMPRESSION) level = 6;
+#endif
+    if (level < 0 || level > 9 || strategy < 0 || strategy > Z_FIXED) {
+        return Z_STREAM_ERROR;
+    }
+    func = configuration_table[s->level].func;
+
+    if (func != configuration_table[level].func && strm->total_in != 0) {
+        /* Flush the last buffer: */
+        err = deflate(strm, Z_PARTIAL_FLUSH);
+    }
+    if (s->level != level) {
+        s->level = level;
+        s->max_lazy_match   = configuration_table[level].max_lazy;
+        s->good_match       = configuration_table[level].good_length;
+        s->nice_match       = configuration_table[level].nice_length;
+        s->max_chain_length = configuration_table[level].max_chain;
+    }
+    s->strategy = strategy;
+    return err;
+}
+
+/* ========================================================================= */
+int ZEXPORT deflateTune(strm, good_length, max_lazy, nice_length, max_chain)
+    z_streamp strm;
+    int good_length;
+    int max_lazy;
+    int nice_length;
+    int max_chain;
+{
+    deflate_state *s;
+
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    s = strm->state;
+    s->good_match = good_length;
+    s->max_lazy_match = max_lazy;
+    s->nice_match = nice_length;
+    s->max_chain_length = max_chain;
+    return Z_OK;
+}
+
+/* =========================================================================
+ * For the default windowBits of 15 and memLevel of 8, this function returns
+ * a close to exact, as well as small, upper bound on the compressed size.
+ * They are coded as constants here for a reason--if the #define's are
+ * changed, then this function needs to be changed as well.  The return
+ * value for 15 and 8 only works for those exact settings.
+ *
+ * For any setting other than those defaults for windowBits and memLevel,
+ * the value returned is a conservative worst case for the maximum expansion
+ * resulting from using fixed blocks instead of stored blocks, which deflate
+ * can emit on compressed data for some combinations of the parameters.
+ *
+ * This function could be more sophisticated to provide closer upper bounds
+ * for every combination of windowBits and memLevel, as well as wrap.
+ * But even the conservative upper bound of about 14% expansion does not
+ * seem onerous for output buffer allocation.
+ */
+uLong ZEXPORT deflateBound(strm, sourceLen)
+    z_streamp strm;
+    uLong sourceLen;
+{
+    deflate_state *s;
+    uLong destLen;
+
+    /* conservative upper bound */
+    destLen = sourceLen +
+              ((sourceLen + 7) >> 3) + ((sourceLen + 63) >> 6) + 11;
+
+    /* if can't get parameters, return conservative bound */
+    if (strm == Z_NULL || strm->state == Z_NULL)
+        return destLen;
+
+    /* if not default parameters, return conservative bound */
+    s = strm->state;
+    if (s->w_bits != 15 || s->hash_bits != 8 + 7)
+        return destLen;
+
+    /* default settings: return tight bound for that case */
+    return compressBound(sourceLen);
+}
+
+/* =========================================================================
+ * Put a short in the pending buffer. The 16-bit value is put in MSB order.
+ * IN assertion: the stream state is correct and there is enough room in
+ * pending_buf.
+ */
+local void putShortMSB (s, b)
+    deflate_state *s;
+    uInt b;
+{
+    put_byte(s, (Byte)(b >> 8));
+    put_byte(s, (Byte)(b & 0xff));
+}
+
+/* =========================================================================
+ * Flush as much pending output as possible. All deflate() output goes
+ * through this function so some applications may wish to modify it
+ * to avoid allocating a large strm->next_out buffer and copying into it.
+ * (See also read_buf()).
+ */
+local void flush_pending(strm)
+    z_streamp strm;
+{
+    unsigned len = strm->state->pending;
+
+    if (len > strm->avail_out) len = strm->avail_out;
+    if (len == 0) return;
+
+    zmemcpy(strm->next_out, strm->state->pending_out, len);
+    strm->next_out  += len;
+    strm->state->pending_out  += len;
+    strm->total_out += len;
+    strm->avail_out  -= len;
+    strm->state->pending -= len;
+    if (strm->state->pending == 0) {
+        strm->state->pending_out = strm->state->pending_buf;
+    }
+}
+
+/* ========================================================================= */
+int ZEXPORT deflate (strm, flush)
+    z_streamp strm;
+    int flush;
+{
+    int old_flush; /* value of flush param for previous deflate call */
+    deflate_state *s;
+
+    if (strm == Z_NULL || strm->state == Z_NULL ||
+        flush > Z_FINISH || flush < 0) {
+        return Z_STREAM_ERROR;
+    }
+    s = strm->state;
+
+    if (strm->next_out == Z_NULL ||
+        (strm->next_in == Z_NULL && strm->avail_in != 0) ||
+        (s->status == FINISH_STATE && flush != Z_FINISH)) {
+        ERR_RETURN(strm, Z_STREAM_ERROR);
+    }
+    if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
+
+    s->strm = strm; /* just in case */
+    old_flush = s->last_flush;
+    s->last_flush = flush;
+
+    /* Write the header */
+    if (s->status == INIT_STATE) {
+#ifdef GZIP
+        if (s->wrap == 2) {
+            strm->adler = crc32(0L, Z_NULL, 0);
+            put_byte(s, 31);
+            put_byte(s, 139);
+            put_byte(s, 8);
+            if (s->gzhead == NULL) {
+                put_byte(s, 0);
+                put_byte(s, 0);
+                put_byte(s, 0);
+                put_byte(s, 0);
+                put_byte(s, 0);
+                put_byte(s, s->level == 9 ? 2 :
+                            (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ?
+                             4 : 0));
+                put_byte(s, OS_CODE);
+                s->status = BUSY_STATE;
+            }
+            else {
+                put_byte(s, (s->gzhead->text ? 1 : 0) +
+                            (s->gzhead->hcrc ? 2 : 0) +
+                            (s->gzhead->extra == Z_NULL ? 0 : 4) +
+                            (s->gzhead->name == Z_NULL ? 0 : 8) +
+                            (s->gzhead->comment == Z_NULL ? 0 : 16)
+                        );
+                put_byte(s, (Byte)(s->gzhead->time & 0xff));
+                put_byte(s, (Byte)((s->gzhead->time >> 8) & 0xff));
+                put_byte(s, (Byte)((s->gzhead->time >> 16) & 0xff));
+                put_byte(s, (Byte)((s->gzhead->time >> 24) & 0xff));
+                put_byte(s, s->level == 9 ? 2 :
+                            (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ?
+                             4 : 0));
+                put_byte(s, s->gzhead->os & 0xff);
+                if (s->gzhead->extra != NULL) {
+                    put_byte(s, s->gzhead->extra_len & 0xff);
+                    put_byte(s, (s->gzhead->extra_len >> 8) & 0xff);
+                }
+                if (s->gzhead->hcrc)
+                    strm->adler = crc32(strm->adler, s->pending_buf,
+                                        s->pending);
+                s->gzindex = 0;
+                s->status = EXTRA_STATE;
+            }
+        }
+        else
+#endif
+        {
+            uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
+            uInt level_flags;
+
+            if (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2)
+                level_flags = 0;
+            else if (s->level < 6)
+                level_flags = 1;
+            else if (s->level == 6)
+                level_flags = 2;
+            else
+                level_flags = 3;
+            header |= (level_flags << 6);
+            if (s->strstart != 0) header |= PRESET_DICT;
+            header += 31 - (header % 31);
+
+            s->status = BUSY_STATE;
+            putShortMSB(s, header);
+
+            /* Save the adler32 of the preset dictionary: */
+            if (s->strstart != 0) {
+                putShortMSB(s, (uInt)(strm->adler >> 16));
+                putShortMSB(s, (uInt)(strm->adler & 0xffff));
+            }
+            strm->adler = adler32(0L, Z_NULL, 0);
+        }
+    }
+#ifdef GZIP
+    if (s->status == EXTRA_STATE) {
+        if (s->gzhead->extra != NULL) {
+            uInt beg = s->pending;  /* start of bytes to update crc */
+
+            while (s->gzindex < (s->gzhead->extra_len & 0xffff)) {
+                if (s->pending == s->pending_buf_size) {
+                    if (s->gzhead->hcrc && s->pending > beg)
+                        strm->adler = crc32(strm->adler, s->pending_buf + beg,
+                                            s->pending - beg);
+                    flush_pending(strm);
+                    beg = s->pending;
+                    if (s->pending == s->pending_buf_size)
+                        break;
+                }
+                put_byte(s, s->gzhead->extra[s->gzindex]);
+                s->gzindex++;
+            }
+            if (s->gzhead->hcrc && s->pending > beg)
+                strm->adler = crc32(strm->adler, s->pending_buf + beg,
+                                    s->pending - beg);
+            if (s->gzindex == s->gzhead->extra_len) {
+                s->gzindex = 0;
+                s->status = NAME_STATE;
+            }
+        }
+        else
+            s->status = NAME_STATE;
+    }
+    if (s->status == NAME_STATE) {
+        if (s->gzhead->name != NULL) {
+            uInt beg = s->pending;  /* start of bytes to update crc */
+            int val;
+
+            do {
+                if (s->pending == s->pending_buf_size) {
+                    if (s->gzhead->hcrc && s->pending > beg)
+                        strm->adler = crc32(strm->adler, s->pending_buf + beg,
+                                            s->pending - beg);
+                    flush_pending(strm);
+                    beg = s->pending;
+                    if (s->pending == s->pending_buf_size) {
+                        val = 1;
+                        break;
+                    }
+                }
+                val = s->gzhead->name[s->gzindex++];
+                put_byte(s, val);
+            } while (val != 0);
+            if (s->gzhead->hcrc && s->pending > beg)
+                strm->adler = crc32(strm->adler, s->pending_buf + beg,
+                                    s->pending - beg);
+            if (val == 0) {
+                s->gzindex = 0;
+                s->status = COMMENT_STATE;
+            }
+        }
+        else
+            s->status = COMMENT_STATE;
+    }
+    if (s->status == COMMENT_STATE) {
+        if (s->gzhead->comment != NULL) {
+            uInt beg = s->pending;  /* start of bytes to update crc */
+            int val;
+
+            do {
+                if (s->pending == s->pending_buf_size) {
+                    if (s->gzhead->hcrc && s->pending > beg)
+                        strm->adler = crc32(strm->adler, s->pending_buf + beg,
+                                            s->pending - beg);
+                    flush_pending(strm);
+                    beg = s->pending;
+                    if (s->pending == s->pending_buf_size) {
+                        val = 1;
+                        break;
+                    }
+                }
+                val = s->gzhead->comment[s->gzindex++];
+                put_byte(s, val);
+            } while (val != 0);
+            if (s->gzhead->hcrc && s->pending > beg)
+                strm->adler = crc32(strm->adler, s->pending_buf + beg,
+                                    s->pending - beg);
+            if (val == 0)
+                s->status = HCRC_STATE;
+        }
+        else
+            s->status = HCRC_STATE;
+    }
+    if (s->status == HCRC_STATE) {
+        if (s->gzhead->hcrc) {
+            if (s->pending + 2 > s->pending_buf_size)
+                flush_pending(strm);
+            if (s->pending + 2 <= s->pending_buf_size) {
+                put_byte(s, (Byte)(strm->adler & 0xff));
+                put_byte(s, (Byte)((strm->adler >> 8) & 0xff));
+                strm->adler = crc32(0L, Z_NULL, 0);
+                s->status = BUSY_STATE;
+            }
+        }
+        else
+            s->status = BUSY_STATE;
+    }
+#endif
+
+    /* Flush as much pending output as possible */
+    if (s->pending != 0) {
+        flush_pending(strm);
+        if (strm->avail_out == 0) {
+            /* Since avail_out is 0, deflate will be called again with
+             * more output space, but possibly with both pending and
+             * avail_in equal to zero. There won't be anything to do,
+             * but this is not an error situation so make sure we
+             * return OK instead of BUF_ERROR at next call of deflate:
+             */
+            s->last_flush = -1;
+            return Z_OK;
+        }
+
+    /* Make sure there is something to do and avoid duplicate consecutive
+     * flushes. For repeated and useless calls with Z_FINISH, we keep
+     * returning Z_STREAM_END instead of Z_BUF_ERROR.
+     */
+    } else if (strm->avail_in == 0 && flush <= old_flush &&
+               flush != Z_FINISH) {
+        ERR_RETURN(strm, Z_BUF_ERROR);
+    }
+
+    /* User must not provide more input after the first FINISH: */
+    if (s->status == FINISH_STATE && strm->avail_in != 0) {
+        ERR_RETURN(strm, Z_BUF_ERROR);
+    }
+
+    /* Start a new block or continue the current one.
+     */
+    if (strm->avail_in != 0 || s->lookahead != 0 ||
+        (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
+        block_state bstate;
+
+        bstate = (*(configuration_table[s->level].func))(s, flush);
+
+        if (bstate == finish_started || bstate == finish_done) {
+            s->status = FINISH_STATE;
+        }
+        if (bstate == need_more || bstate == finish_started) {
+            if (strm->avail_out == 0) {
+                s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
+            }
+            return Z_OK;
+            /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
+             * of deflate should use the same flush parameter to make sure
+             * that the flush is complete. So we don't have to output an
+             * empty block here, this will be done at next call. This also
+             * ensures that for a very small output buffer, we emit at most
+             * one empty block.
+             */
+        }
+        if (bstate == block_done) {
+            if (flush == Z_PARTIAL_FLUSH) {
+                _tr_align(s);
+            } else { /* FULL_FLUSH or SYNC_FLUSH */
+                _tr_stored_block(s, (char*)0, 0L, 0);
+                /* For a full flush, this empty block will be recognized
+                 * as a special marker by inflate_sync().
+                 */
+                if (flush == Z_FULL_FLUSH) {
+                    CLEAR_HASH(s);             /* forget history */
+                }
+            }
+            flush_pending(strm);
+            if (strm->avail_out == 0) {
+              s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
+              return Z_OK;
+            }
+        }
+    }
+    Assert(strm->avail_out > 0, "bug2");
+
+    if (flush != Z_FINISH) return Z_OK;
+    if (s->wrap <= 0) return Z_STREAM_END;
+
+    /* Write the trailer */
+#ifdef GZIP
+    if (s->wrap == 2) {
+        put_byte(s, (Byte)(strm->adler & 0xff));
+        put_byte(s, (Byte)((strm->adler >> 8) & 0xff));
+        put_byte(s, (Byte)((strm->adler >> 16) & 0xff));
+        put_byte(s, (Byte)((strm->adler >> 24) & 0xff));
+        put_byte(s, (Byte)(strm->total_in & 0xff));
+        put_byte(s, (Byte)((strm->total_in >> 8) & 0xff));
+        put_byte(s, (Byte)((strm->total_in >> 16) & 0xff));
+        put_byte(s, (Byte)((strm->total_in >> 24) & 0xff));
+    }
+    else
+#endif
+    {
+        putShortMSB(s, (uInt)(strm->adler >> 16));
+        putShortMSB(s, (uInt)(strm->adler & 0xffff));
+    }
+    flush_pending(strm);
+    /* If avail_out is zero, the application will call deflate again
+     * to flush the rest.
+     */
+    if (s->wrap > 0) s->wrap = -s->wrap; /* write the trailer only once! */
+    return s->pending != 0 ? Z_OK : Z_STREAM_END;
+}
+
+/* ========================================================================= */
+int ZEXPORT deflateEnd (strm)
+    z_streamp strm;
+{
+    int status;
+
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+
+    status = strm->state->status;
+    if (status != INIT_STATE &&
+        status != EXTRA_STATE &&
+        status != NAME_STATE &&
+        status != COMMENT_STATE &&
+        status != HCRC_STATE &&
+        status != BUSY_STATE &&
+        status != FINISH_STATE) {
+      return Z_STREAM_ERROR;
+    }
+
+    /* Deallocate in reverse order of allocations: */
+    TRY_FREE(strm, strm->state->pending_buf);
+    TRY_FREE(strm, strm->state->head);
+    TRY_FREE(strm, strm->state->prev);
+    TRY_FREE(strm, strm->state->window);
+
+    ZFREE(strm, strm->state);
+    strm->state = Z_NULL;
+
+    return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
+}
+
+/* =========================================================================
+ * Copy the source state to the destination state.
+ * To simplify the source, this is not supported for 16-bit MSDOS (which
+ * doesn't have enough memory anyway to duplicate compression states).
+ */
+int ZEXPORT deflateCopy (dest, source)
+    z_streamp dest;
+    z_streamp source;
+{
+#ifdef MAXSEG_64K
+    return Z_STREAM_ERROR;
+#else
+    deflate_state *ds;
+    deflate_state *ss;
+    ushf *overlay;
+
+
+    if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {
+        return Z_STREAM_ERROR;
+    }
+
+    ss = source->state;
+
+    zmemcpy(dest, source, sizeof(z_stream));
+
+    ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
+    if (ds == Z_NULL) return Z_MEM_ERROR;
+    dest->state = (struct internal_state FAR *) ds;
+    zmemcpy(ds, ss, sizeof(deflate_state));
+    ds->strm = dest;
+
+    ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
+    ds->prev   = (Posf *)  ZALLOC(dest, ds->w_size, sizeof(Pos));
+    ds->head   = (Posf *)  ZALLOC(dest, ds->hash_size, sizeof(Pos));
+    overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
+    ds->pending_buf = (uchf *) overlay;
+
+    if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
+        ds->pending_buf == Z_NULL) {
+        deflateEnd (dest);
+        return Z_MEM_ERROR;
+    }
+    /* following zmemcpy do not work for 16-bit MSDOS */
+    zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
+    zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
+    zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
+    zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
+
+    ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
+    ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
+    ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
+
+    ds->l_desc.dyn_tree = ds->dyn_ltree;
+    ds->d_desc.dyn_tree = ds->dyn_dtree;
+    ds->bl_desc.dyn_tree = ds->bl_tree;
+
+    return Z_OK;
+#endif /* MAXSEG_64K */
+}
+
+/* ===========================================================================
+ * Read a new buffer from the current input stream, update the adler32
+ * and total number of bytes read.  All deflate() input goes through
+ * this function so some applications may wish to modify it to avoid
+ * allocating a large strm->next_in buffer and copying from it.
+ * (See also flush_pending()).
+ */
+local int read_buf(strm, buf, size)
+    z_streamp strm;
+    Bytef *buf;
+    unsigned size;
+{
+    unsigned len = strm->avail_in;
+
+    if (len > size) len = size;
+    if (len == 0) return 0;
+
+    strm->avail_in  -= len;
+
+    if (strm->state->wrap == 1) {
+        strm->adler = adler32(strm->adler, strm->next_in, len);
+    }
+#ifdef GZIP
+    else if (strm->state->wrap == 2) {
+        strm->adler = crc32(strm->adler, strm->next_in, len);
+    }
+#endif
+    zmemcpy(buf, strm->next_in, len);
+    strm->next_in  += len;
+    strm->total_in += len;
+
+    return (int)len;
+}
+
+/* ===========================================================================
+ * Initialize the "longest match" routines for a new zlib stream
+ */
+local void lm_init (s)
+    deflate_state *s;
+{
+    s->window_size = (ulg)2L*s->w_size;
+
+    CLEAR_HASH(s);
+
+    /* Set the default configuration parameters:
+     */
+    s->max_lazy_match   = configuration_table[s->level].max_lazy;
+    s->good_match       = configuration_table[s->level].good_length;
+    s->nice_match       = configuration_table[s->level].nice_length;
+    s->max_chain_length = configuration_table[s->level].max_chain;
+
+    s->strstart = 0;
+    s->block_start = 0L;
+    s->lookahead = 0;
+    s->match_length = s->prev_length = MIN_MATCH-1;
+    s->match_available = 0;
+    s->ins_h = 0;
+#ifndef FASTEST
+#ifdef ASMV
+    match_init(); /* initialize the asm code */
+#endif
+#endif
+}
+
+#ifndef FASTEST
+/* ===========================================================================
+ * Set match_start to the longest match starting at the given string and
+ * return its length. Matches shorter or equal to prev_length are discarded,
+ * in which case the result is equal to prev_length and match_start is
+ * garbage.
+ * IN assertions: cur_match is the head of the hash chain for the current
+ *   string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
+ * OUT assertion: the match length is not greater than s->lookahead.
+ */
+#ifndef ASMV
+/* For 80x86 and 680x0, an optimized version will be provided in match.asm or
+ * match.S. The code will be functionally equivalent.
+ */
+local uInt longest_match(s, cur_match)
+    deflate_state *s;
+    IPos cur_match;                             /* current match */
+{
+    unsigned chain_length = s->max_chain_length;/* max hash chain length */
+    register Bytef *scan = s->window + s->strstart; /* current string */
+    register Bytef *match;                       /* matched string */
+    register int len;                           /* length of current match */
+    int best_len = s->prev_length;              /* best match length so far */
+    int nice_match = s->nice_match;             /* stop if match long enough */
+    IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
+        s->strstart - (IPos)MAX_DIST(s) : NIL;
+    /* Stop when cur_match becomes <= limit. To simplify the code,
+     * we prevent matches with the string of window index 0.
+     */
+    Posf *prev = s->prev;
+    uInt wmask = s->w_mask;
+
+#ifdef UNALIGNED_OK
+    /* Compare two bytes at a time. Note: this is not always beneficial.
+     * Try with and without -DUNALIGNED_OK to check.
+     */
+    register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
+    register ush scan_start = *(ushf*)scan;
+    register ush scan_end   = *(ushf*)(scan+best_len-1);
+#else
+    register Bytef *strend = s->window + s->strstart + MAX_MATCH;
+    register Byte scan_end1  = scan[best_len-1];
+    register Byte scan_end   = scan[best_len];
+#endif
+
+    /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
+     * It is easy to get rid of this optimization if necessary.
+     */
+    Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
+
+    /* Do not waste too much time if we already have a good match: */
+    if (s->prev_length >= s->good_match) {
+        chain_length >>= 2;
+    }
+    /* Do not look for matches beyond the end of the input. This is necessary
+     * to make deflate deterministic.
+     */
+    if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
+
+    Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
+
+    do {
+        Assert(cur_match < s->strstart, "no future");
+        match = s->window + cur_match;
+
+        /* Skip to next match if the match length cannot increase
+         * or if the match length is less than 2.  Note that the checks below
+         * for insufficient lookahead only occur occasionally for performance
+         * reasons.  Therefore uninitialized memory will be accessed, and
+         * conditional jumps will be made that depend on those values.
+         * However the length of the match is limited to the lookahead, so
+         * the output of deflate is not affected by the uninitialized values.
+         */
+#if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
+        /* This code assumes sizeof(unsigned short) == 2. Do not use
+         * UNALIGNED_OK if your compiler uses a different size.
+         */
+        if (*(ushf*)(match+best_len-1) != scan_end ||
+            *(ushf*)match != scan_start) continue;
+
+        /* It is not necessary to compare scan[2] and match[2] since they are
+         * always equal when the other bytes match, given that the hash keys
+         * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
+         * strstart+3, +5, ... up to strstart+257. We check for insufficient
+         * lookahead only every 4th comparison; the 128th check will be made
+         * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
+         * necessary to put more guard bytes at the end of the window, or
+         * to check more often for insufficient lookahead.
+         */
+        Assert(scan[2] == match[2], "scan[2]?");
+        scan++, match++;
+        do {
+        } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
+                 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
+                 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
+                 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
+                 scan < strend);
+        /* The funny "do {}" generates better code on most compilers */
+
+        /* Here, scan <= window+strstart+257 */
+        Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
+        if (*scan == *match) scan++;
+
+        len = (MAX_MATCH - 1) - (int)(strend-scan);
+        scan = strend - (MAX_MATCH-1);
+
+#else /* UNALIGNED_OK */
+
+        if (match[best_len]   != scan_end  ||
+            match[best_len-1] != scan_end1 ||
+            *match            != *scan     ||
+            *++match          != scan[1])      continue;
+
+        /* The check at best_len-1 can be removed because it will be made
+         * again later. (This heuristic is not always a win.)
+         * It is not necessary to compare scan[2] and match[2] since they
+         * are always equal when the other bytes match, given that
+         * the hash keys are equal and that HASH_BITS >= 8.
+         */
+        scan += 2, match++;
+        Assert(*scan == *match, "match[2]?");
+
+        /* We check for insufficient lookahead only every 8th comparison;
+         * the 256th check will be made at strstart+258.
+         */
+        do {
+        } while (*++scan == *++match && *++scan == *++match &&
+                 *++scan == *++match && *++scan == *++match &&
+                 *++scan == *++match && *++scan == *++match &&
+                 *++scan == *++match && *++scan == *++match &&
+                 scan < strend);
+
+        Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
+
+        len = MAX_MATCH - (int)(strend - scan);
+        scan = strend - MAX_MATCH;
+
+#endif /* UNALIGNED_OK */
+
+        if (len > best_len) {
+            s->match_start = cur_match;
+            best_len = len;
+            if (len >= nice_match) break;
+#ifdef UNALIGNED_OK
+            scan_end = *(ushf*)(scan+best_len-1);
+#else
+            scan_end1  = scan[best_len-1];
+            scan_end   = scan[best_len];
+#endif
+        }
+    } while ((cur_match = prev[cur_match & wmask]) > limit
+             && --chain_length != 0);
+
+    if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
+    return s->lookahead;
+}
+#endif /* ASMV */
+#endif /* FASTEST */
+
+/* ---------------------------------------------------------------------------
+ * Optimized version for level == 1 or strategy == Z_RLE only
+ */
+local uInt longest_match_fast(s, cur_match)
+    deflate_state *s;
+    IPos cur_match;                             /* current match */
+{
+    register Bytef *scan = s->window + s->strstart; /* current string */
+    register Bytef *match;                       /* matched string */
+    register int len;                           /* length of current match */
+    register Bytef *strend = s->window + s->strstart + MAX_MATCH;
+
+    /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
+     * It is easy to get rid of this optimization if necessary.
+     */
+    Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
+
+    Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
+
+    Assert(cur_match < s->strstart, "no future");
+
+    match = s->window + cur_match;
+
+    /* Return failure if the match length is less than 2:
+     */
+    if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1;
+
+    /* The check at best_len-1 can be removed because it will be made
+     * again later. (This heuristic is not always a win.)
+     * It is not necessary to compare scan[2] and match[2] since they
+     * are always equal when the other bytes match, given that
+     * the hash keys are equal and that HASH_BITS >= 8.
+     */
+    scan += 2, match += 2;
+    Assert(*scan == *match, "match[2]?");
+
+    /* We check for insufficient lookahead only every 8th comparison;
+     * the 256th check will be made at strstart+258.
+     */
+    do {
+    } while (*++scan == *++match && *++scan == *++match &&
+             *++scan == *++match && *++scan == *++match &&
+             *++scan == *++match && *++scan == *++match &&
+             *++scan == *++match && *++scan == *++match &&
+             scan < strend);
+
+    Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
+
+    len = MAX_MATCH - (int)(strend - scan);
+
+    if (len < MIN_MATCH) return MIN_MATCH - 1;
+
+    s->match_start = cur_match;
+    return (uInt)len <= s->lookahead ? (uInt)len : s->lookahead;
+}
+
+#ifdef DEBUG
+/* ===========================================================================
+ * Check that the match at match_start is indeed a match.
+ */
+local void check_match(s, start, match, length)
+    deflate_state *s;
+    IPos start, match;
+    int length;
+{
+    /* check that the match is indeed a match */
+    if (zmemcmp(s->window + match,
+                s->window + start, length) != EQUAL) {
+        fprintf(stderr, " start %u, match %u, length %d\n",
+                start, match, length);
+        do {
+            fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
+        } while (--length != 0);
+        z_error("invalid match");
+    }
+    if (z_verbose > 1) {
+        fprintf(stderr,"\\[%d,%d]", start-match, length);
+        do { putc(s->window[start++], stderr); } while (--length != 0);
+    }
+}
+#else
+#  define check_match(s, start, match, length)
+#endif /* DEBUG */
+
+/* ===========================================================================
+ * Fill the window when the lookahead becomes insufficient.
+ * Updates strstart and lookahead.
+ *
+ * IN assertion: lookahead < MIN_LOOKAHEAD
+ * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
+ *    At least one byte has been read, or avail_in == 0; reads are
+ *    performed for at least two bytes (required for the zip translate_eol
+ *    option -- not supported here).
+ */
+local void fill_window(s)
+    deflate_state *s;
+{
+    register unsigned n, m;
+    register Posf *p;
+    unsigned more;    /* Amount of free space at the end of the window. */
+    uInt wsize = s->w_size;
+
+    do {
+        more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
+
+        /* Deal with !@#$% 64K limit: */
+        if (sizeof(int) <= 2) {
+            if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
+                more = wsize;
+
+            } else if (more == (unsigned)(-1)) {
+                /* Very unlikely, but possible on 16 bit machine if
+                 * strstart == 0 && lookahead == 1 (input done a byte at time)
+                 */
+                more--;
+            }
+        }
+
+        /* If the window is almost full and there is insufficient lookahead,
+         * move the upper half to the lower one to make room in the upper half.
+         */
+        if (s->strstart >= wsize+MAX_DIST(s)) {
+
+            zmemcpy(s->window, s->window+wsize, (unsigned)wsize);
+            s->match_start -= wsize;
+            s->strstart    -= wsize; /* we now have strstart >= MAX_DIST */
+            s->block_start -= (long) wsize;
+
+            /* Slide the hash table (could be avoided with 32 bit values
+               at the expense of memory usage). We slide even when level == 0
+               to keep the hash table consistent if we switch back to level > 0
+               later. (Using level 0 permanently is not an optimal usage of
+               zlib, so we don't care about this pathological case.)
+             */
+            /* %%% avoid this when Z_RLE */
+            n = s->hash_size;
+            p = &s->head[n];
+            do {
+                m = *--p;
+                *p = (Pos)(m >= wsize ? m-wsize : NIL);
+            } while (--n);
+
+            n = wsize;
+#ifndef FASTEST
+            p = &s->prev[n];
+            do {
+                m = *--p;
+                *p = (Pos)(m >= wsize ? m-wsize : NIL);
+                /* If n is not on any hash chain, prev[n] is garbage but
+                 * its value will never be used.
+                 */
+            } while (--n);
+#endif
+            more += wsize;
+        }
+        if (s->strm->avail_in == 0) return;
+
+        /* If there was no sliding:
+         *    strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
+         *    more == window_size - lookahead - strstart
+         * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
+         * => more >= window_size - 2*WSIZE + 2
+         * In the BIG_MEM or MMAP case (not yet supported),
+         *   window_size == input_size + MIN_LOOKAHEAD  &&
+         *   strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
+         * Otherwise, window_size == 2*WSIZE so more >= 2.
+         * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
+         */
+        Assert(more >= 2, "more < 2");
+
+        n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);
+        s->lookahead += n;
+
+        /* Initialize the hash value now that we have some input: */
+        if (s->lookahead >= MIN_MATCH) {
+            s->ins_h = s->window[s->strstart];
+            UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
+#if MIN_MATCH != 3
+            Call UPDATE_HASH() MIN_MATCH-3 more times
+#endif
+        }
+        /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
+         * but this is not important since only literal bytes will be emitted.
+         */
+
+    } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
+}
+
+/* ===========================================================================
+ * Flush the current block, with given end-of-file flag.
+ * IN assertion: strstart is set to the end of the current match.
+ */
+#define FLUSH_BLOCK_ONLY(s, eof) { \
+   _tr_flush_block(s, (s->block_start >= 0L ? \
+                   (charf *)&s->window[(unsigned)s->block_start] : \
+                   (charf *)Z_NULL), \
+                (ulg)((long)s->strstart - s->block_start), \
+                (eof)); \
+   s->block_start = s->strstart; \
+   flush_pending(s->strm); \
+   Tracev((stderr,"[FLUSH]")); \
+}
+
+/* Same but force premature exit if necessary. */
+#define FLUSH_BLOCK(s, eof) { \
+   FLUSH_BLOCK_ONLY(s, eof); \
+   if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
+}
+
+/* ===========================================================================
+ * Copy without compression as much as possible from the input stream, return
+ * the current block state.
+ * This function does not insert new strings in the dictionary since
+ * uncompressible data is probably not useful. This function is used
+ * only for the level=0 compression option.
+ * NOTE: this function should be optimized to avoid extra copying from
+ * window to pending_buf.
+ */
+local block_state deflate_stored(s, flush)
+    deflate_state *s;
+    int flush;
+{
+    /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
+     * to pending_buf_size, and each stored block has a 5 byte header:
+     */
+    ulg max_block_size = 0xffff;
+    ulg max_start;
+
+    if (max_block_size > s->pending_buf_size - 5) {
+        max_block_size = s->pending_buf_size - 5;
+    }
+
+    /* Copy as much as possible from input to output: */
+    for (;;) {
+        /* Fill the window as much as possible: */
+        if (s->lookahead <= 1) {
+
+            Assert(s->strstart < s->w_size+MAX_DIST(s) ||
+                   s->block_start >= (long)s->w_size, "slide too late");
+
+            fill_window(s);
+            if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
+
+            if (s->lookahead == 0) break; /* flush the current block */
+        }
+        Assert(s->block_start >= 0L, "block gone");
+
+        s->strstart += s->lookahead;
+        s->lookahead = 0;
+
+        /* Emit a stored block if pending_buf will be full: */
+        max_start = s->block_start + max_block_size;
+        if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
+            /* strstart == 0 is possible when wraparound on 16-bit machine */
+            s->lookahead = (uInt)(s->strstart - max_start);
+            s->strstart = (uInt)max_start;
+            FLUSH_BLOCK(s, 0);
+        }
+        /* Flush if we may have to slide, otherwise block_start may become
+         * negative and the data will be gone:
+         */
+        if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
+            FLUSH_BLOCK(s, 0);
+        }
+    }
+    FLUSH_BLOCK(s, flush == Z_FINISH);
+    return flush == Z_FINISH ? finish_done : block_done;
+}
+
+/* ===========================================================================
+ * Compress as much as possible from the input stream, return the current
+ * block state.
+ * This function does not perform lazy evaluation of matches and inserts
+ * new strings in the dictionary only for unmatched strings or for short
+ * matches. It is used only for the fast compression options.
+ */
+local block_state deflate_fast(s, flush)
+    deflate_state *s;
+    int flush;
+{
+    IPos hash_head = NIL; /* head of the hash chain */
+    int bflush;           /* set if current block must be flushed */
+
+    for (;;) {
+        /* Make sure that we always have enough lookahead, except
+         * at the end of the input file. We need MAX_MATCH bytes
+         * for the next match, plus MIN_MATCH bytes to insert the
+         * string following the next match.
+         */
+        if (s->lookahead < MIN_LOOKAHEAD) {
+            fill_window(s);
+            if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
+                return need_more;
+            }
+            if (s->lookahead == 0) break; /* flush the current block */
+        }
+
+        /* Insert the string window[strstart .. strstart+2] in the
+         * dictionary, and set hash_head to the head of the hash chain:
+         */
+        if (s->lookahead >= MIN_MATCH) {
+            INSERT_STRING(s, s->strstart, hash_head);
+        }
+
+        /* Find the longest match, discarding those <= prev_length.
+         * At this point we have always match_length < MIN_MATCH
+         */
+        if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
+            /* To simplify the code, we prevent matches with the string
+             * of window index 0 (in particular we have to avoid a match
+             * of the string with itself at the start of the input file).
+             */
+#ifdef FASTEST
+            if ((s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) ||
+                (s->strategy == Z_RLE && s->strstart - hash_head == 1)) {
+                s->match_length = longest_match_fast (s, hash_head);
+            }
+#else
+            if (s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) {
+                s->match_length = longest_match (s, hash_head);
+            } else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) {
+                s->match_length = longest_match_fast (s, hash_head);
+            }
+#endif
+            /* longest_match() or longest_match_fast() sets match_start */
+        }
+        if (s->match_length >= MIN_MATCH) {
+            check_match(s, s->strstart, s->match_start, s->match_length);
+
+            _tr_tally_dist(s, s->strstart - s->match_start,
+                           s->match_length - MIN_MATCH, bflush);
+
+            s->lookahead -= s->match_length;
+
+            /* Insert new strings in the hash table only if the match length
+             * is not too large. This saves time but degrades compression.
+             */
+#ifndef FASTEST
+            if (s->match_length <= s->max_insert_length &&
+                s->lookahead >= MIN_MATCH) {
+                s->match_length--; /* string at strstart already in table */
+                do {
+                    s->strstart++;
+                    INSERT_STRING(s, s->strstart, hash_head);
+                    /* strstart never exceeds WSIZE-MAX_MATCH, so there are
+                     * always MIN_MATCH bytes ahead.
+                     */
+                } while (--s->match_length != 0);
+                s->strstart++;
+            } else
+#endif
+            {
+                s->strstart += s->match_length;
+                s->match_length = 0;
+                s->ins_h = s->window[s->strstart];
+                UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
+#if MIN_MATCH != 3
+                Call UPDATE_HASH() MIN_MATCH-3 more times
+#endif
+                /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
+                 * matter since it will be recomputed at next deflate call.
+                 */
+            }
+        } else {
+            /* No match, output a literal byte */
+            Tracevv((stderr,"%c", s->window[s->strstart]));
+            _tr_tally_lit (s, s->window[s->strstart], bflush);
+            s->lookahead--;
+            s->strstart++;
+        }
+        if (bflush) FLUSH_BLOCK(s, 0);
+    }
+    FLUSH_BLOCK(s, flush == Z_FINISH);
+    return flush == Z_FINISH ? finish_done : block_done;
+}
+
+#ifndef FASTEST
+/* ===========================================================================
+ * Same as above, but achieves better compression. We use a lazy
+ * evaluation for matches: a match is finally adopted only if there is
+ * no better match at the next window position.
+ */
+local block_state deflate_slow(s, flush)
+    deflate_state *s;
+    int flush;
+{
+    IPos hash_head = NIL;    /* head of hash chain */
+    int bflush;              /* set if current block must be flushed */
+
+    /* Process the input block. */
+    for (;;) {
+        /* Make sure that we always have enough lookahead, except
+         * at the end of the input file. We need MAX_MATCH bytes
+         * for the next match, plus MIN_MATCH bytes to insert the
+         * string following the next match.
+         */
+        if (s->lookahead < MIN_LOOKAHEAD) {
+            fill_window(s);
+            if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
+                return need_more;
+            }
+            if (s->lookahead == 0) break; /* flush the current block */
+        }
+
+        /* Insert the string window[strstart .. strstart+2] in the
+         * dictionary, and set hash_head to the head of the hash chain:
+         */
+        if (s->lookahead >= MIN_MATCH) {
+            INSERT_STRING(s, s->strstart, hash_head);
+        }
+
+        /* Find the longest match, discarding those <= prev_length.
+         */
+        s->prev_length = s->match_length, s->prev_match = s->match_start;
+        s->match_length = MIN_MATCH-1;
+
+        if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
+            s->strstart - hash_head <= MAX_DIST(s)) {
+            /* To simplify the code, we prevent matches with the string
+             * of window index 0 (in particular we have to avoid a match
+             * of the string with itself at the start of the input file).
+             */
+            if (s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) {
+                s->match_length = longest_match (s, hash_head);
+            } else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) {
+                s->match_length = longest_match_fast (s, hash_head);
+            }
+            /* longest_match() or longest_match_fast() sets match_start */
+
+            if (s->match_length <= 5 && (s->strategy == Z_FILTERED
+#if TOO_FAR <= 32767
+                || (s->match_length == MIN_MATCH &&
+                    s->strstart - s->match_start > TOO_FAR)
+#endif
+                )) {
+
+                /* If prev_match is also MIN_MATCH, match_start is garbage
+                 * but we will ignore the current match anyway.
+                 */
+                s->match_length = MIN_MATCH-1;
+            }
+        }
+        /* If there was a match at the previous step and the current
+         * match is not better, output the previous match:
+         */
+        if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
+            uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
+            /* Do not insert strings in hash table beyond this. */
+
+            check_match(s, s->strstart-1, s->prev_match, s->prev_length);
+
+            _tr_tally_dist(s, s->strstart -1 - s->prev_match,
+                           s->prev_length - MIN_MATCH, bflush);
+
+            /* Insert in hash table all strings up to the end of the match.
+             * strstart-1 and strstart are already inserted. If there is not
+             * enough lookahead, the last two strings are not inserted in
+             * the hash table.
+             */
+            s->lookahead -= s->prev_length-1;
+            s->prev_length -= 2;
+            do {
+                if (++s->strstart <= max_insert) {
+                    INSERT_STRING(s, s->strstart, hash_head);
+                }
+            } while (--s->prev_length != 0);
+            s->match_available = 0;
+            s->match_length = MIN_MATCH-1;
+            s->strstart++;
+
+            if (bflush) FLUSH_BLOCK(s, 0);
+
+        } else if (s->match_available) {
+            /* If there was no match at the previous position, output a
+             * single literal. If there was a match but the current match
+             * is longer, truncate the previous match to a single literal.
+             */
+            Tracevv((stderr,"%c", s->window[s->strstart-1]));
+            _tr_tally_lit(s, s->window[s->strstart-1], bflush);
+            if (bflush) {
+                FLUSH_BLOCK_ONLY(s, 0);
+            }
+            s->strstart++;
+            s->lookahead--;
+            if (s->strm->avail_out == 0) return need_more;
+        } else {
+            /* There is no previous match to compare with, wait for
+             * the next step to decide.
+             */
+            s->match_available = 1;
+            s->strstart++;
+            s->lookahead--;
+        }
+    }
+    Assert (flush != Z_NO_FLUSH, "no flush?");
+    if (s->match_available) {
+        Tracevv((stderr,"%c", s->window[s->strstart-1]));
+        _tr_tally_lit(s, s->window[s->strstart-1], bflush);
+        s->match_available = 0;
+    }
+    FLUSH_BLOCK(s, flush == Z_FINISH);
+    return flush == Z_FINISH ? finish_done : block_done;
+}
+#endif /* FASTEST */
+
+#if 0
+/* ===========================================================================
+ * For Z_RLE, simply look for runs of bytes, generate matches only of distance
+ * one.  Do not maintain a hash table.  (It will be regenerated if this run of
+ * deflate switches away from Z_RLE.)
+ */
+local block_state deflate_rle(s, flush)
+    deflate_state *s;
+    int flush;
+{
+    int bflush;         /* set if current block must be flushed */
+    uInt run;           /* length of run */
+    uInt max;           /* maximum length of run */
+    uInt prev;          /* byte at distance one to match */
+    Bytef *scan;        /* scan for end of run */
+
+    for (;;) {
+        /* Make sure that we always have enough lookahead, except
+         * at the end of the input file. We need MAX_MATCH bytes
+         * for the longest encodable run.
+         */
+        if (s->lookahead < MAX_MATCH) {
+            fill_window(s);
+            if (s->lookahead < MAX_MATCH && flush == Z_NO_FLUSH) {
+                return need_more;
+            }
+            if (s->lookahead == 0) break; /* flush the current block */
+        }
+
+        /* See how many times the previous byte repeats */
+        run = 0;
+        if (s->strstart > 0) {      /* if there is a previous byte, that is */
+            max = s->lookahead < MAX_MATCH ? s->lookahead : MAX_MATCH;
+            scan = s->window + s->strstart - 1;
+            prev = *scan++;
+            do {
+                if (*scan++ != prev)
+                    break;
+            } while (++run < max);
+        }
+
+        /* Emit match if have run of MIN_MATCH or longer, else emit literal */
+        if (run >= MIN_MATCH) {
+            check_match(s, s->strstart, s->strstart - 1, run);
+            _tr_tally_dist(s, 1, run - MIN_MATCH, bflush);
+            s->lookahead -= run;
+            s->strstart += run;
+        } else {
+            /* No match, output a literal byte */
+            Tracevv((stderr,"%c", s->window[s->strstart]));
+            _tr_tally_lit (s, s->window[s->strstart], bflush);
+            s->lookahead--;
+            s->strstart++;
+        }
+        if (bflush) FLUSH_BLOCK(s, 0);
+    }
+    FLUSH_BLOCK(s, flush == Z_FINISH);
+    return flush == Z_FINISH ? finish_done : block_done;
+}
+#endif
diff --git a/gs/zlib/deflate.h b/gs/zlib/deflate.h
new file mode 100644
index 000000000..05a5ab3a2
--- /dev/null
+++ b/gs/zlib/deflate.h
@@ -0,0 +1,331 @@
+/* deflate.h -- internal compression state
+ * Copyright (C) 1995-2004 Jean-loup Gailly
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* WARNING: this file should *not* be used by applications. It is
+   part of the implementation of the compression library and is
+   subject to change. Applications should only use zlib.h.
+ */
+
+/* @(#) $Id$ */
+
+#ifndef DEFLATE_H
+#define DEFLATE_H
+
+#include "zutil.h"
+
+/* define NO_GZIP when compiling if you want to disable gzip header and
+   trailer creation by deflate().  NO_GZIP would be used to avoid linking in
+   the crc code when it is not needed.  For shared libraries, gzip encoding
+   should be left enabled. */
+#ifndef NO_GZIP
+#  define GZIP
+#endif
+
+/* ===========================================================================
+ * Internal compression state.
+ */
+
+#define LENGTH_CODES 29
+/* number of length codes, not counting the special END_BLOCK code */
+
+#define LITERALS  256
+/* number of literal bytes 0..255 */
+
+#define L_CODES (LITERALS+1+LENGTH_CODES)
+/* number of Literal or Length codes, including the END_BLOCK code */
+
+#define D_CODES   30
+/* number of distance codes */
+
+#define BL_CODES  19
+/* number of codes used to transfer the bit lengths */
+
+#define HEAP_SIZE (2*L_CODES+1)
+/* maximum heap size */
+
+#define MAX_BITS 15
+/* All codes must not exceed MAX_BITS bits */
+
+#define INIT_STATE    42
+#define EXTRA_STATE   69
+#define NAME_STATE    73
+#define COMMENT_STATE 91
+#define HCRC_STATE   103
+#define BUSY_STATE   113
+#define FINISH_STATE 666
+/* Stream status */
+
+
+/* Data structure describing a single value and its code string. */
+typedef struct ct_data_s {
+    union {
+        ush  freq;       /* frequency count */
+        ush  code;       /* bit string */
+    } fc;
+    union {
+        ush  dad;        /* father node in Huffman tree */
+        ush  len;        /* length of bit string */
+    } dl;
+} FAR ct_data;
+
+#define Freq fc.freq
+#define Code fc.code
+#define Dad  dl.dad
+#define Len  dl.len
+
+typedef struct static_tree_desc_s  static_tree_desc;
+
+typedef struct tree_desc_s {
+    ct_data *dyn_tree;           /* the dynamic tree */
+    int     max_code;            /* largest code with non zero frequency */
+    static_tree_desc *stat_desc; /* the corresponding static tree */
+} FAR tree_desc;
+
+typedef ush Pos;
+typedef Pos FAR Posf;
+typedef unsigned IPos;
+
+/* A Pos is an index in the character window. We use short instead of int to
+ * save space in the various tables. IPos is used only for parameter passing.
+ */
+
+typedef struct internal_state {
+    z_streamp strm;      /* pointer back to this zlib stream */
+    int   status;        /* as the name implies */
+    Bytef *pending_buf;  /* output still pending */
+    ulg   pending_buf_size; /* size of pending_buf */
+    Bytef *pending_out;  /* next pending byte to output to the stream */
+    uInt   pending;      /* nb of bytes in the pending buffer */
+    int   wrap;          /* bit 0 true for zlib, bit 1 true for gzip */
+    gz_headerp  gzhead;  /* gzip header information to write */
+    uInt   gzindex;      /* where in extra, name, or comment */
+    Byte  method;        /* STORED (for zip only) or DEFLATED */
+    int   last_flush;    /* value of flush param for previous deflate call */
+
+                /* used by deflate.c: */
+
+    uInt  w_size;        /* LZ77 window size (32K by default) */
+    uInt  w_bits;        /* log2(w_size)  (8..16) */
+    uInt  w_mask;        /* w_size - 1 */
+
+    Bytef *window;
+    /* Sliding window. Input bytes are read into the second half of the window,
+     * and move to the first half later to keep a dictionary of at least wSize
+     * bytes. With this organization, matches are limited to a distance of
+     * wSize-MAX_MATCH bytes, but this ensures that IO is always
+     * performed with a length multiple of the block size. Also, it limits
+     * the window size to 64K, which is quite useful on MSDOS.
+     * To do: use the user input buffer as sliding window.
+     */
+
+    ulg window_size;
+    /* Actual size of window: 2*wSize, except when the user input buffer
+     * is directly used as sliding window.
+     */
+
+    Posf *prev;
+    /* Link to older string with same hash index. To limit the size of this
+     * array to 64K, this link is maintained only for the last 32K strings.
+     * An index in this array is thus a window index modulo 32K.
+     */
+
+    Posf *head; /* Heads of the hash chains or NIL. */
+
+    uInt  ins_h;          /* hash index of string to be inserted */
+    uInt  hash_size;      /* number of elements in hash table */
+    uInt  hash_bits;      /* log2(hash_size) */
+    uInt  hash_mask;      /* hash_size-1 */
+
+    uInt  hash_shift;
+    /* Number of bits by which ins_h must be shifted at each input
+     * step. It must be such that after MIN_MATCH steps, the oldest
+     * byte no longer takes part in the hash key, that is:
+     *   hash_shift * MIN_MATCH >= hash_bits
+     */
+
+    long block_start;
+    /* Window position at the beginning of the current output block. Gets
+     * negative when the window is moved backwards.
+     */
+
+    uInt match_length;           /* length of best match */
+    IPos prev_match;             /* previous match */
+    int match_available;         /* set if previous match exists */
+    uInt strstart;               /* start of string to insert */
+    uInt match_start;            /* start of matching string */
+    uInt lookahead;              /* number of valid bytes ahead in window */
+
+    uInt prev_length;
+    /* Length of the best match at previous step. Matches not greater than this
+     * are discarded. This is used in the lazy match evaluation.
+     */
+
+    uInt max_chain_length;
+    /* To speed up deflation, hash chains are never searched beyond this
+     * length.  A higher limit improves compression ratio but degrades the
+     * speed.
+     */
+
+    uInt max_lazy_match;
+    /* Attempt to find a better match only when the current match is strictly
+     * smaller than this value. This mechanism is used only for compression
+     * levels >= 4.
+     */
+#   define max_insert_length  max_lazy_match
+    /* Insert new strings in the hash table only if the match length is not
+     * greater than this length. This saves time but degrades compression.
+     * max_insert_length is used only for compression levels <= 3.
+     */
+
+    int level;    /* compression level (1..9) */
+    int strategy; /* favor or force Huffman coding*/
+
+    uInt good_match;
+    /* Use a faster search when the previous match is longer than this */
+
+    int nice_match; /* Stop searching when current match exceeds this */
+
+                /* used by trees.c: */
+    /* Didn't use ct_data typedef below to supress compiler warning */
+    struct ct_data_s dyn_ltree[HEAP_SIZE];   /* literal and length tree */
+    struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
+    struct ct_data_s bl_tree[2*BL_CODES+1];  /* Huffman tree for bit lengths */
+
+    struct tree_desc_s l_desc;               /* desc. for literal tree */
+    struct tree_desc_s d_desc;               /* desc. for distance tree */
+    struct tree_desc_s bl_desc;              /* desc. for bit length tree */
+
+    ush bl_count[MAX_BITS+1];
+    /* number of codes at each bit length for an optimal tree */
+
+    int heap[2*L_CODES+1];      /* heap used to build the Huffman trees */
+    int heap_len;               /* number of elements in the heap */
+    int heap_max;               /* element of largest frequency */
+    /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
+     * The same heap array is used to build all trees.
+     */
+
+    uch depth[2*L_CODES+1];
+    /* Depth of each subtree used as tie breaker for trees of equal frequency
+     */
+
+    uchf *l_buf;          /* buffer for literals or lengths */
+
+    uInt  lit_bufsize;
+    /* Size of match buffer for literals/lengths.  There are 4 reasons for
+     * limiting lit_bufsize to 64K:
+     *   - frequencies can be kept in 16 bit counters
+     *   - if compression is not successful for the first block, all input
+     *     data is still in the window so we can still emit a stored block even
+     *     when input comes from standard input.  (This can also be done for
+     *     all blocks if lit_bufsize is not greater than 32K.)
+     *   - if compression is not successful for a file smaller than 64K, we can
+     *     even emit a stored file instead of a stored block (saving 5 bytes).
+     *     This is applicable only for zip (not gzip or zlib).
+     *   - creating new Huffman trees less frequently may not provide fast
+     *     adaptation to changes in the input data statistics. (Take for
+     *     example a binary file with poorly compressible code followed by
+     *     a highly compressible string table.) Smaller buffer sizes give
+     *     fast adaptation but have of course the overhead of transmitting
+     *     trees more frequently.
+     *   - I can't count above 4
+     */
+
+    uInt last_lit;      /* running index in l_buf */
+
+    ushf *d_buf;
+    /* Buffer for distances. To simplify the code, d_buf and l_buf have
+     * the same number of elements. To use different lengths, an extra flag
+     * array would be necessary.
+     */
+
+    ulg opt_len;        /* bit length of current block with optimal trees */
+    ulg static_len;     /* bit length of current block with static trees */
+    uInt matches;       /* number of string matches in current block */
+    int last_eob_len;   /* bit length of EOB code for last block */
+
+#ifdef DEBUG
+    ulg compressed_len; /* total bit length of compressed file mod 2^32 */
+    ulg bits_sent;      /* bit length of compressed data sent mod 2^32 */
+#endif
+
+    ush bi_buf;
+    /* Output buffer. bits are inserted starting at the bottom (least
+     * significant bits).
+     */
+    int bi_valid;
+    /* Number of valid bits in bi_buf.  All bits above the last valid bit
+     * are always zero.
+     */
+
+} FAR deflate_state;
+
+/* Output a byte on the stream.
+ * IN assertion: there is enough room in pending_buf.
+ */
+#define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
+
+
+#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
+/* Minimum amount of lookahead, except at the end of the input file.
+ * See deflate.c for comments about the MIN_MATCH+1.
+ */
+
+#define MAX_DIST(s)  ((s)->w_size-MIN_LOOKAHEAD)
+/* In order to simplify the code, particularly on 16 bit machines, match
+ * distances are limited to MAX_DIST instead of WSIZE.
+ */
+
+        /* in trees.c */
+void _tr_init         OF((deflate_state *s));
+int  _tr_tally        OF((deflate_state *s, unsigned dist, unsigned lc));
+void _tr_flush_block  OF((deflate_state *s, charf *buf, ulg stored_len,
+                          int eof));
+void _tr_align        OF((deflate_state *s));
+void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
+                          int eof));
+
+#define d_code(dist) \
+   ((dist) < 256 ? _dist_code[dist] : _dist_code[256+((dist)>>7)])
+/* Mapping from a distance to a distance code. dist is the distance - 1 and
+ * must not have side effects. _dist_code[256] and _dist_code[257] are never
+ * used.
+ */
+
+#ifndef DEBUG
+/* Inline versions of _tr_tally for speed: */
+
+#if defined(GEN_TREES_H) || !defined(STDC)
+  extern uch _length_code[];
+  extern uch _dist_code[];
+#else
+  extern const uch _length_code[];
+  extern const uch _dist_code[];
+#endif
+
+# define _tr_tally_lit(s, c, flush) \
+  { uch cc = (c); \
+    s->d_buf[s->last_lit] = 0; \
+    s->l_buf[s->last_lit++] = cc; \
+    s->dyn_ltree[cc].Freq++; \
+    flush = (s->last_lit == s->lit_bufsize-1); \
+   }
+# define _tr_tally_dist(s, distance, length, flush) \
+  { uch len = (length); \
+    ush dist = (distance); \
+    s->d_buf[s->last_lit] = dist; \
+    s->l_buf[s->last_lit++] = len; \
+    dist--; \
+    s->dyn_ltree[_length_code[len]+LITERALS+1].Freq++; \
+    s->dyn_dtree[d_code(dist)].Freq++; \
+    flush = (s->last_lit == s->lit_bufsize-1); \
+  }
+#else
+# define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c)
+# define _tr_tally_dist(s, distance, length, flush) \
+              flush = _tr_tally(s, distance, length)
+#endif
+
+#endif /* DEFLATE_H */
diff --git a/gs/zlib/example.c b/gs/zlib/example.c
new file mode 100644
index 000000000..6c8a0ee76
--- /dev/null
+++ b/gs/zlib/example.c
@@ -0,0 +1,565 @@
+/* example.c -- usage example of the zlib compression library
+ * Copyright (C) 1995-2004 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* @(#) $Id$ */
+
+#include <stdio.h>
+#include "zlib.h"
+
+#ifdef STDC
+#  include <string.h>
+#  include <stdlib.h>
+#endif
+
+#if defined(VMS) || defined(RISCOS)
+#  define TESTFILE "foo-gz"
+#else
+#  define TESTFILE "foo.gz"
+#endif
+
+#define CHECK_ERR(err, msg) { \
+    if (err != Z_OK) { \
+        fprintf(stderr, "%s error: %d\n", msg, err); \
+        exit(1); \
+    } \
+}
+
+const char hello[] = "hello, hello!";
+/* "hello world" would be more standard, but the repeated "hello"
+ * stresses the compression code better, sorry...
+ */
+
+const char dictionary[] = "hello";
+uLong dictId; /* Adler32 value of the dictionary */
+
+void test_compress      OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_gzio          OF((const char *fname,
+                            Byte *uncompr, uLong uncomprLen));
+void test_deflate       OF((Byte *compr, uLong comprLen));
+void test_inflate       OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_large_deflate OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_large_inflate OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_flush         OF((Byte *compr, uLong *comprLen));
+void test_sync          OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_dict_deflate  OF((Byte *compr, uLong comprLen));
+void test_dict_inflate  OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+int  main               OF((int argc, char *argv[]));
+
+/* ===========================================================================
+ * Test compress() and uncompress()
+ */
+void test_compress(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    uLong len = (uLong)strlen(hello)+1;
+
+    err = compress(compr, &comprLen, (const Bytef*)hello, len);
+    CHECK_ERR(err, "compress");
+
+    strcpy((char*)uncompr, "garbage");
+
+    err = uncompress(uncompr, &uncomprLen, compr, comprLen);
+    CHECK_ERR(err, "uncompress");
+
+    if (strcmp((char*)uncompr, hello)) {
+        fprintf(stderr, "bad uncompress\n");
+        exit(1);
+    } else {
+        printf("uncompress(): %s\n", (char *)uncompr);
+    }
+}
+
+/* ===========================================================================
+ * Test read/write of .gz files
+ */
+void test_gzio(fname, uncompr, uncomprLen)
+    const char *fname; /* compressed file name */
+    Byte *uncompr;
+    uLong uncomprLen;
+{
+#ifdef NO_GZCOMPRESS
+    fprintf(stderr, "NO_GZCOMPRESS -- gz* functions cannot compress\n");
+#else
+    int err;
+    int len = (int)strlen(hello)+1;
+    gzFile file;
+    z_off_t pos;
+
+    file = gzopen(fname, "wb");
+    if (file == NULL) {
+        fprintf(stderr, "gzopen error\n");
+        exit(1);
+    }
+    gzputc(file, 'h');
+    if (gzputs(file, "ello") != 4) {
+        fprintf(stderr, "gzputs err: %s\n", gzerror(file, &err));
+        exit(1);
+    }
+    if (gzprintf(file, ", %s!", "hello") != 8) {
+        fprintf(stderr, "gzprintf err: %s\n", gzerror(file, &err));
+        exit(1);
+    }
+    gzseek(file, 1L, SEEK_CUR); /* add one zero byte */
+    gzclose(file);
+
+    file = gzopen(fname, "rb");
+    if (file == NULL) {
+        fprintf(stderr, "gzopen error\n");
+        exit(1);
+    }
+    strcpy((char*)uncompr, "garbage");
+
+    if (gzread(file, uncompr, (unsigned)uncomprLen) != len) {
+        fprintf(stderr, "gzread err: %s\n", gzerror(file, &err));
+        exit(1);
+    }
+    if (strcmp((char*)uncompr, hello)) {
+        fprintf(stderr, "bad gzread: %s\n", (char*)uncompr);
+        exit(1);
+    } else {
+        printf("gzread(): %s\n", (char*)uncompr);
+    }
+
+    pos = gzseek(file, -8L, SEEK_CUR);
+    if (pos != 6 || gztell(file) != pos) {
+        fprintf(stderr, "gzseek error, pos=%ld, gztell=%ld\n",
+                (long)pos, (long)gztell(file));
+        exit(1);
+    }
+
+    if (gzgetc(file) != ' ') {
+        fprintf(stderr, "gzgetc error\n");
+        exit(1);
+    }
+
+    if (gzungetc(' ', file) != ' ') {
+        fprintf(stderr, "gzungetc error\n");
+        exit(1);
+    }
+
+    gzgets(file, (char*)uncompr, (int)uncomprLen);
+    if (strlen((char*)uncompr) != 7) { /* " hello!" */
+        fprintf(stderr, "gzgets err after gzseek: %s\n", gzerror(file, &err));
+        exit(1);
+    }
+    if (strcmp((char*)uncompr, hello + 6)) {
+        fprintf(stderr, "bad gzgets after gzseek\n");
+        exit(1);
+    } else {
+        printf("gzgets() after gzseek: %s\n", (char*)uncompr);
+    }
+
+    gzclose(file);
+#endif
+}
+
+/* ===========================================================================
+ * Test deflate() with small buffers
+ */
+void test_deflate(compr, comprLen)
+    Byte *compr;
+    uLong comprLen;
+{
+    z_stream c_stream; /* compression stream */
+    int err;
+    uLong len = (uLong)strlen(hello)+1;
+
+    c_stream.zalloc = (alloc_func)0;
+    c_stream.zfree = (free_func)0;
+    c_stream.opaque = (voidpf)0;
+
+    err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
+    CHECK_ERR(err, "deflateInit");
+
+    c_stream.next_in  = (Bytef*)hello;
+    c_stream.next_out = compr;
+
+    while (c_stream.total_in != len && c_stream.total_out < comprLen) {
+        c_stream.avail_in = c_stream.avail_out = 1; /* force small buffers */
+        err = deflate(&c_stream, Z_NO_FLUSH);
+        CHECK_ERR(err, "deflate");
+    }
+    /* Finish the stream, still forcing small buffers: */
+    for (;;) {
+        c_stream.avail_out = 1;
+        err = deflate(&c_stream, Z_FINISH);
+        if (err == Z_STREAM_END) break;
+        CHECK_ERR(err, "deflate");
+    }
+
+    err = deflateEnd(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+}
+
+/* ===========================================================================
+ * Test inflate() with small buffers
+ */
+void test_inflate(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    z_stream d_stream; /* decompression stream */
+
+    strcpy((char*)uncompr, "garbage");
+
+    d_stream.zalloc = (alloc_func)0;
+    d_stream.zfree = (free_func)0;
+    d_stream.opaque = (voidpf)0;
+
+    d_stream.next_in  = compr;
+    d_stream.avail_in = 0;
+    d_stream.next_out = uncompr;
+
+    err = inflateInit(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    while (d_stream.total_out < uncomprLen && d_stream.total_in < comprLen) {
+        d_stream.avail_in = d_stream.avail_out = 1; /* force small buffers */
+        err = inflate(&d_stream, Z_NO_FLUSH);
+        if (err == Z_STREAM_END) break;
+        CHECK_ERR(err, "inflate");
+    }
+
+    err = inflateEnd(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    if (strcmp((char*)uncompr, hello)) {
+        fprintf(stderr, "bad inflate\n");
+        exit(1);
+    } else {
+        printf("inflate(): %s\n", (char *)uncompr);
+    }
+}
+
+/* ===========================================================================
+ * Test deflate() with large buffers and dynamic change of compression level
+ */
+void test_large_deflate(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    z_stream c_stream; /* compression stream */
+    int err;
+
+    c_stream.zalloc = (alloc_func)0;
+    c_stream.zfree = (free_func)0;
+    c_stream.opaque = (voidpf)0;
+
+    err = deflateInit(&c_stream, Z_BEST_SPEED);
+    CHECK_ERR(err, "deflateInit");
+
+    c_stream.next_out = compr;
+    c_stream.avail_out = (uInt)comprLen;
+
+    /* At this point, uncompr is still mostly zeroes, so it should compress
+     * very well:
+     */
+    c_stream.next_in = uncompr;
+    c_stream.avail_in = (uInt)uncomprLen;
+    err = deflate(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate");
+    if (c_stream.avail_in != 0) {
+        fprintf(stderr, "deflate not greedy\n");
+        exit(1);
+    }
+
+    /* Feed in already compressed data and switch to no compression: */
+    deflateParams(&c_stream, Z_NO_COMPRESSION, Z_DEFAULT_STRATEGY);
+    c_stream.next_in = compr;
+    c_stream.avail_in = (uInt)comprLen/2;
+    err = deflate(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate");
+
+    /* Switch back to compressing mode: */
+    deflateParams(&c_stream, Z_BEST_COMPRESSION, Z_FILTERED);
+    c_stream.next_in = uncompr;
+    c_stream.avail_in = (uInt)uncomprLen;
+    err = deflate(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate");
+
+    err = deflate(&c_stream, Z_FINISH);
+    if (err != Z_STREAM_END) {
+        fprintf(stderr, "deflate should report Z_STREAM_END\n");
+        exit(1);
+    }
+    err = deflateEnd(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+}
+
+/* ===========================================================================
+ * Test inflate() with large buffers
+ */
+void test_large_inflate(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    z_stream d_stream; /* decompression stream */
+
+    strcpy((char*)uncompr, "garbage");
+
+    d_stream.zalloc = (alloc_func)0;
+    d_stream.zfree = (free_func)0;
+    d_stream.opaque = (voidpf)0;
+
+    d_stream.next_in  = compr;
+    d_stream.avail_in = (uInt)comprLen;
+
+    err = inflateInit(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    for (;;) {
+        d_stream.next_out = uncompr;            /* discard the output */
+        d_stream.avail_out = (uInt)uncomprLen;
+        err = inflate(&d_stream, Z_NO_FLUSH);
+        if (err == Z_STREAM_END) break;
+        CHECK_ERR(err, "large inflate");
+    }
+
+    err = inflateEnd(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    if (d_stream.total_out != 2*uncomprLen + comprLen/2) {
+        fprintf(stderr, "bad large inflate: %ld\n", d_stream.total_out);
+        exit(1);
+    } else {
+        printf("large_inflate(): OK\n");
+    }
+}
+
+/* ===========================================================================
+ * Test deflate() with full flush
+ */
+void test_flush(compr, comprLen)
+    Byte *compr;
+    uLong *comprLen;
+{
+    z_stream c_stream; /* compression stream */
+    int err;
+    uInt len = (uInt)strlen(hello)+1;
+
+    c_stream.zalloc = (alloc_func)0;
+    c_stream.zfree = (free_func)0;
+    c_stream.opaque = (voidpf)0;
+
+    err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
+    CHECK_ERR(err, "deflateInit");
+
+    c_stream.next_in  = (Bytef*)hello;
+    c_stream.next_out = compr;
+    c_stream.avail_in = 3;
+    c_stream.avail_out = (uInt)*comprLen;
+    err = deflate(&c_stream, Z_FULL_FLUSH);
+    CHECK_ERR(err, "deflate");
+
+    compr[3]++; /* force an error in first compressed block */
+    c_stream.avail_in = len - 3;
+
+    err = deflate(&c_stream, Z_FINISH);
+    if (err != Z_STREAM_END) {
+        CHECK_ERR(err, "deflate");
+    }
+    err = deflateEnd(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+
+    *comprLen = c_stream.total_out;
+}
+
+/* ===========================================================================
+ * Test inflateSync()
+ */
+void test_sync(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    z_stream d_stream; /* decompression stream */
+
+    strcpy((char*)uncompr, "garbage");
+
+    d_stream.zalloc = (alloc_func)0;
+    d_stream.zfree = (free_func)0;
+    d_stream.opaque = (voidpf)0;
+
+    d_stream.next_in  = compr;
+    d_stream.avail_in = 2; /* just read the zlib header */
+
+    err = inflateInit(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    d_stream.next_out = uncompr;
+    d_stream.avail_out = (uInt)uncomprLen;
+
+    inflate(&d_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "inflate");
+
+    d_stream.avail_in = (uInt)comprLen-2;   /* read all compressed data */
+    err = inflateSync(&d_stream);           /* but skip the damaged part */
+    CHECK_ERR(err, "inflateSync");
+
+    err = inflate(&d_stream, Z_FINISH);
+    if (err != Z_DATA_ERROR) {
+        fprintf(stderr, "inflate should report DATA_ERROR\n");
+        /* Because of incorrect adler32 */
+        exit(1);
+    }
+    err = inflateEnd(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    printf("after inflateSync(): hel%s\n", (char *)uncompr);
+}
+
+/* ===========================================================================
+ * Test deflate() with preset dictionary
+ */
+void test_dict_deflate(compr, comprLen)
+    Byte *compr;
+    uLong comprLen;
+{
+    z_stream c_stream; /* compression stream */
+    int err;
+
+    c_stream.zalloc = (alloc_func)0;
+    c_stream.zfree = (free_func)0;
+    c_stream.opaque = (voidpf)0;
+
+    err = deflateInit(&c_stream, Z_BEST_COMPRESSION);
+    CHECK_ERR(err, "deflateInit");
+
+    err = deflateSetDictionary(&c_stream,
+                               (const Bytef*)dictionary, sizeof(dictionary));
+    CHECK_ERR(err, "deflateSetDictionary");
+
+    dictId = c_stream.adler;
+    c_stream.next_out = compr;
+    c_stream.avail_out = (uInt)comprLen;
+
+    c_stream.next_in = (Bytef*)hello;
+    c_stream.avail_in = (uInt)strlen(hello)+1;
+
+    err = deflate(&c_stream, Z_FINISH);
+    if (err != Z_STREAM_END) {
+        fprintf(stderr, "deflate should report Z_STREAM_END\n");
+        exit(1);
+    }
+    err = deflateEnd(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+}
+
+/* ===========================================================================
+ * Test inflate() with a preset dictionary
+ */
+void test_dict_inflate(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    z_stream d_stream; /* decompression stream */
+
+    strcpy((char*)uncompr, "garbage");
+
+    d_stream.zalloc = (alloc_func)0;
+    d_stream.zfree = (free_func)0;
+    d_stream.opaque = (voidpf)0;
+
+    d_stream.next_in  = compr;
+    d_stream.avail_in = (uInt)comprLen;
+
+    err = inflateInit(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    d_stream.next_out = uncompr;
+    d_stream.avail_out = (uInt)uncomprLen;
+
+    for (;;) {
+        err = inflate(&d_stream, Z_NO_FLUSH);
+        if (err == Z_STREAM_END) break;
+        if (err == Z_NEED_DICT) {
+            if (d_stream.adler != dictId) {
+                fprintf(stderr, "unexpected dictionary");
+                exit(1);
+            }
+            err = inflateSetDictionary(&d_stream, (const Bytef*)dictionary,
+                                       sizeof(dictionary));
+        }
+        CHECK_ERR(err, "inflate with dict");
+    }
+
+    err = inflateEnd(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    if (strcmp((char*)uncompr, hello)) {
+        fprintf(stderr, "bad inflate with dict\n");
+        exit(1);
+    } else {
+        printf("inflate with dictionary: %s\n", (char *)uncompr);
+    }
+}
+
+/* ===========================================================================
+ * Usage:  example [output.gz  [input.gz]]
+ */
+
+int main(argc, argv)
+    int argc;
+    char *argv[];
+{
+    Byte *compr, *uncompr;
+    uLong comprLen = 10000*sizeof(int); /* don't overflow on MSDOS */
+    uLong uncomprLen = comprLen;
+    static const char* myVersion = ZLIB_VERSION;
+
+    if (zlibVersion()[0] != myVersion[0]) {
+        fprintf(stderr, "incompatible zlib version\n");
+        exit(1);
+
+    } else if (strcmp(zlibVersion(), ZLIB_VERSION) != 0) {
+        fprintf(stderr, "warning: different zlib version\n");
+    }
+
+    printf("zlib version %s = 0x%04x, compile flags = 0x%lx\n",
+            ZLIB_VERSION, ZLIB_VERNUM, zlibCompileFlags());
+
+    compr    = (Byte*)calloc((uInt)comprLen, 1);
+    uncompr  = (Byte*)calloc((uInt)uncomprLen, 1);
+    /* compr and uncompr are cleared to avoid reading uninitialized
+     * data and to ensure that uncompr compresses well.
+     */
+    if (compr == Z_NULL || uncompr == Z_NULL) {
+        printf("out of memory\n");
+        exit(1);
+    }
+    test_compress(compr, comprLen, uncompr, uncomprLen);
+
+    test_gzio((argc > 1 ? argv[1] : TESTFILE),
+              uncompr, uncomprLen);
+
+    test_deflate(compr, comprLen);
+    test_inflate(compr, comprLen, uncompr, uncomprLen);
+
+    test_large_deflate(compr, comprLen, uncompr, uncomprLen);
+    test_large_inflate(compr, comprLen, uncompr, uncomprLen);
+
+    test_flush(compr, &comprLen);
+    test_sync(compr, comprLen, uncompr, uncomprLen);
+    comprLen = uncomprLen;
+
+    test_dict_deflate(compr, comprLen);
+    test_dict_inflate(compr, comprLen, uncompr, uncomprLen);
+
+    free(compr);
+    free(uncompr);
+
+    return 0;
+}
diff --git a/gs/zlib/examples/README.examples b/gs/zlib/examples/README.examples
new file mode 100644
index 000000000..5632d7a4c
--- /dev/null
+++ b/gs/zlib/examples/README.examples
@@ -0,0 +1,42 @@
+This directory contains examples of the use of zlib.
+
+fitblk.c
+    compress just enough input to nearly fill a requested output size
+    - zlib isn't designed to do this, but fitblk does it anyway
+
+gun.c
+    uncompress a gzip file
+    - illustrates the use of inflateBack() for high speed file-to-file
+      decompression using call-back functions
+    - is approximately twice as fast as gzip -d
+    - also provides Unix uncompress functionality, again twice as fast
+
+gzappend.c
+    append to a gzip file
+    - illustrates the use of the Z_BLOCK flush parameter for inflate()
+    - illustrates the use of deflatePrime() to start at any bit
+
+gzjoin.c
+    join gzip files without recalculating the crc or recompressing
+    - illustrates the use of the Z_BLOCK flush parameter for inflate()
+    - illustrates the use of crc32_combine()
+
+gzlog.c
+gzlog.h
+    efficiently maintain a message log file in gzip format
+    - illustrates use of raw deflate and Z_SYNC_FLUSH
+    - illustrates use of gzip header extra field
+
+zlib_how.html
+    painfully comprehensive description of zpipe.c (see below)
+    - describes in excruciating detail the use of deflate() and inflate()
+
+zpipe.c
+    reads and writes zlib streams from stdin to stdout
+    - illustrates the proper use of deflate() and inflate()
+    - deeply commented in zlib_how.html (see above)
+
+zran.c
+    index a zlib or gzip stream and randomly access it
+    - illustrates the use of Z_BLOCK, inflatePrime(), and
+      inflateSetDictionary() to provide random access
diff --git a/gs/zlib/examples/fitblk.c b/gs/zlib/examples/fitblk.c
new file mode 100644
index 000000000..c61de5c99
--- /dev/null
+++ b/gs/zlib/examples/fitblk.c
@@ -0,0 +1,233 @@
+/* fitblk.c: example of fitting compressed output to a specified size
+   Not copyrighted -- provided to the public domain
+   Version 1.1  25 November 2004  Mark Adler */
+
+/* Version history:
+   1.0  24 Nov 2004  First version
+   1.1  25 Nov 2004  Change deflateInit2() to deflateInit()
+                     Use fixed-size, stack-allocated raw buffers
+                     Simplify code moving compression to subroutines
+                     Use assert() for internal errors
+                     Add detailed description of approach
+ */
+
+/* Approach to just fitting a requested compressed size:
+
+   fitblk performs three compression passes on a portion of the input
+   data in order to determine how much of that input will compress to
+   nearly the requested output block size.  The first pass generates
+   enough deflate blocks to produce output to fill the requested
+   output size plus a specfied excess amount (see the EXCESS define
+   below).  The last deflate block may go quite a bit past that, but
+   is discarded.  The second pass decompresses and recompresses just
+   the compressed data that fit in the requested plus excess sized
+   buffer.  The deflate process is terminated after that amount of
+   input, which is less than the amount consumed on the first pass.
+   The last deflate block of the result will be of a comparable size
+   to the final product, so that the header for that deflate block and
+   the compression ratio for that block will be about the same as in
+   the final product.  The third compression pass decompresses the
+   result of the second step, but only the compressed data up to the
+   requested size minus an amount to allow the compressed stream to
+   complete (see the MARGIN define below).  That will result in a
+   final compressed stream whose length is less than or equal to the
+   requested size.  Assuming sufficient input and a requested size
+   greater than a few hundred bytes, the shortfall will typically be
+   less than ten bytes.
+
+   If the input is short enough that the first compression completes
+   before filling the requested output size, then that compressed
+   stream is return with no recompression.
+
+   EXCESS is chosen to be just greater than the shortfall seen in a
+   two pass approach similar to the above.  That shortfall is due to
+   the last deflate block compressing more efficiently with a smaller
+   header on the second pass.  EXCESS is set to be large enough so
+   that there is enough uncompressed data for the second pass to fill
+   out the requested size, and small enough so that the final deflate
+   block of the second pass will be close in size to the final deflate
+   block of the third and final pass.  MARGIN is chosen to be just
+   large enough to assure that the final compression has enough room
+   to complete in all cases.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include "zlib.h"
+
+#define local static
+
+/* print nastygram and leave */
+local void quit(char *why)
+{
+    fprintf(stderr, "fitblk abort: %s\n", why);
+    exit(1);
+}
+
+#define RAWLEN 4096    /* intermediate uncompressed buffer size */
+
+/* compress from file to def until provided buffer is full or end of
+   input reached; return last deflate() return value, or Z_ERRNO if
+   there was read error on the file */
+local int partcompress(FILE *in, z_streamp def)
+{
+    int ret, flush;
+    unsigned char raw[RAWLEN];
+
+    flush = Z_NO_FLUSH;
+    do {
+        def->avail_in = fread(raw, 1, RAWLEN, in);
+        if (ferror(in))
+            return Z_ERRNO;
+        def->next_in = raw;
+        if (feof(in))
+            flush = Z_FINISH;
+        ret = deflate(def, flush);
+        assert(ret != Z_STREAM_ERROR);
+    } while (def->avail_out != 0 && flush == Z_NO_FLUSH);
+    return ret;
+}
+
+/* recompress from inf's input to def's output; the input for inf and
+   the output for def are set in those structures before calling;
+   return last deflate() return value, or Z_MEM_ERROR if inflate()
+   was not able to allocate enough memory when it needed to */
+local int recompress(z_streamp inf, z_streamp def)
+{
+    int ret, flush;
+    unsigned char raw[RAWLEN];
+
+    flush = Z_NO_FLUSH;
+    do {
+        /* decompress */
+        inf->avail_out = RAWLEN;
+        inf->next_out = raw;
+        ret = inflate(inf, Z_NO_FLUSH);
+        assert(ret != Z_STREAM_ERROR && ret != Z_DATA_ERROR &&
+               ret != Z_NEED_DICT);
+        if (ret == Z_MEM_ERROR)
+            return ret;
+
+        /* compress what was decompresed until done or no room */
+        def->avail_in = RAWLEN - inf->avail_out;
+        def->next_in = raw;
+        if (inf->avail_out != 0)
+            flush = Z_FINISH;
+        ret = deflate(def, flush);
+        assert(ret != Z_STREAM_ERROR);
+    } while (ret != Z_STREAM_END && def->avail_out != 0);
+    return ret;
+}
+
+#define EXCESS 256      /* empirically determined stream overage */
+#define MARGIN 8        /* amount to back off for completion */
+
+/* compress from stdin to fixed-size block on stdout */
+int main(int argc, char **argv)
+{
+    int ret;                /* return code */
+    unsigned size;          /* requested fixed output block size */
+    unsigned have;          /* bytes written by deflate() call */
+    unsigned char *blk;     /* intermediate and final stream */
+    unsigned char *tmp;     /* close to desired size stream */
+    z_stream def, inf;      /* zlib deflate and inflate states */
+
+    /* get requested output size */
+    if (argc != 2)
+        quit("need one argument: size of output block");
+    ret = strtol(argv[1], argv + 1, 10);
+    if (argv[1][0] != 0)
+        quit("argument must be a number");
+    if (ret < 8)            /* 8 is minimum zlib stream size */
+        quit("need positive size of 8 or greater");
+    size = (unsigned)ret;
+
+    /* allocate memory for buffers and compression engine */
+    blk = malloc(size + EXCESS);
+    def.zalloc = Z_NULL;
+    def.zfree = Z_NULL;
+    def.opaque = Z_NULL;
+    ret = deflateInit(&def, Z_DEFAULT_COMPRESSION);
+    if (ret != Z_OK || blk == NULL)
+        quit("out of memory");
+
+    /* compress from stdin until output full, or no more input */
+    def.avail_out = size + EXCESS;
+    def.next_out = blk;
+    ret = partcompress(stdin, &def);
+    if (ret == Z_ERRNO)
+        quit("error reading input");
+
+    /* if it all fit, then size was undersubscribed -- done! */
+    if (ret == Z_STREAM_END && def.avail_out >= EXCESS) {
+        /* write block to stdout */
+        have = size + EXCESS - def.avail_out;
+        if (fwrite(blk, 1, have, stdout) != have || ferror(stdout))
+            quit("error writing output");
+
+        /* clean up and print results to stderr */
+        ret = deflateEnd(&def);
+        assert(ret != Z_STREAM_ERROR);
+        free(blk);
+        fprintf(stderr,
+                "%u bytes unused out of %u requested (all input)\n",
+                size - have, size);
+        return 0;
+    }
+
+    /* it didn't all fit -- set up for recompression */
+    inf.zalloc = Z_NULL;
+    inf.zfree = Z_NULL;
+    inf.opaque = Z_NULL;
+    inf.avail_in = 0;
+    inf.next_in = Z_NULL;
+    ret = inflateInit(&inf);
+    tmp = malloc(size + EXCESS);
+    if (ret != Z_OK || tmp == NULL)
+        quit("out of memory");
+    ret = deflateReset(&def);
+    assert(ret != Z_STREAM_ERROR);
+
+    /* do first recompression close to the right amount */
+    inf.avail_in = size + EXCESS;
+    inf.next_in = blk;
+    def.avail_out = size + EXCESS;
+    def.next_out = tmp;
+    ret = recompress(&inf, &def);
+    if (ret == Z_MEM_ERROR)
+        quit("out of memory");
+
+    /* set up for next reocmpression */
+    ret = inflateReset(&inf);
+    assert(ret != Z_STREAM_ERROR);
+    ret = deflateReset(&def);
+    assert(ret != Z_STREAM_ERROR);
+
+    /* do second and final recompression (third compression) */
+    inf.avail_in = size - MARGIN;   /* assure stream will complete */
+    inf.next_in = tmp;
+    def.avail_out = size;
+    def.next_out = blk;
+    ret = recompress(&inf, &def);
+    if (ret == Z_MEM_ERROR)
+        quit("out of memory");
+    assert(ret == Z_STREAM_END);    /* otherwise MARGIN too small */
+
+    /* done -- write block to stdout */
+    have = size - def.avail_out;
+    if (fwrite(blk, 1, have, stdout) != have || ferror(stdout))
+        quit("error writing output");
+
+    /* clean up and print results to stderr */
+    free(tmp);
+    ret = inflateEnd(&inf);
+    assert(ret != Z_STREAM_ERROR);
+    ret = deflateEnd(&def);
+    assert(ret != Z_STREAM_ERROR);
+    free(blk);
+    fprintf(stderr,
+            "%u bytes unused out of %u requested (%lu input)\n",
+            size - have, size, def.total_in);
+    return 0;
+}
diff --git a/gs/zlib/examples/gun.c b/gs/zlib/examples/gun.c
new file mode 100644
index 000000000..bfec590a0
--- /dev/null
+++ b/gs/zlib/examples/gun.c
@@ -0,0 +1,693 @@
+/* gun.c -- simple gunzip to give an example of the use of inflateBack()
+ * Copyright (C) 2003, 2005 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+   Version 1.3  12 June 2005  Mark Adler */
+
+/* Version history:
+   1.0  16 Feb 2003  First version for testing of inflateBack()
+   1.1  21 Feb 2005  Decompress concatenated gzip streams
+                     Remove use of "this" variable (C++ keyword)
+                     Fix return value for in()
+                     Improve allocation failure checking
+                     Add typecasting for void * structures
+                     Add -h option for command version and usage
+                     Add a bunch of comments
+   1.2  20 Mar 2005  Add Unix compress (LZW) decompression
+                     Copy file attributes from input file to output file
+   1.3  12 Jun 2005  Add casts for error messages [Oberhumer]
+ */
+
+/*
+   gun [ -t ] [ name ... ]
+
+   decompresses the data in the named gzip files.  If no arguments are given,
+   gun will decompress from stdin to stdout.  The names must end in .gz, -gz,
+   .z, -z, _z, or .Z.  The uncompressed data will be written to a file name
+   with the suffix stripped.  On success, the original file is deleted.  On
+   failure, the output file is deleted.  For most failures, the command will
+   continue to process the remaining names on the command line.  A memory
+   allocation failure will abort the command.  If -t is specified, then the
+   listed files or stdin will be tested as gzip files for integrity (without
+   checking for a proper suffix), no output will be written, and no files
+   will be deleted.
+
+   Like gzip, gun allows concatenated gzip streams and will decompress them,
+   writing all of the uncompressed data to the output.  Unlike gzip, gun allows
+   an empty file on input, and will produce no error writing an empty output
+   file.
+
+   gun will also decompress files made by Unix compress, which uses LZW
+   compression.  These files are automatically detected by virtue of their
+   magic header bytes.  Since the end of Unix compress stream is marked by the
+   end-of-file, they cannot be concantenated.  If a Unix compress stream is
+   encountered in an input file, it is the last stream in that file.
+
+   Like gunzip and uncompress, the file attributes of the orignal compressed
+   file are maintained in the final uncompressed file, to the extent that the
+   user permissions allow it.
+
+   On my Mac OS X PowerPC G4, gun is almost twice as fast as gunzip (version
+   1.2.4) is on the same file, when gun is linked with zlib 1.2.2.  Also the
+   LZW decompression provided by gun is about twice as fast as the standard
+   Unix uncompress command.
+ */
+
+/* external functions and related types and constants */
+#include <stdio.h>          /* fprintf() */
+#include <stdlib.h>         /* malloc(), free() */
+#include <string.h>         /* strerror(), strcmp(), strlen(), memcpy() */
+#include <errno.h>          /* errno */
+#include <fcntl.h>          /* open() */
+#include <unistd.h>         /* read(), write(), close(), chown(), unlink() */
+#include <sys/types.h>
+#include <sys/stat.h>       /* stat(), chmod() */
+#include <utime.h>          /* utime() */
+#include "zlib.h"           /* inflateBackInit(), inflateBack(), */
+                            /* inflateBackEnd(), crc32() */
+
+/* function declaration */
+#define local static
+
+/* buffer constants */
+#define SIZE 32768U         /* input and output buffer sizes */
+#define PIECE 16384         /* limits i/o chunks for 16-bit int case */
+
+/* structure for infback() to pass to input function in() -- it maintains the
+   input file and a buffer of size SIZE */
+struct ind {
+    int infile;
+    unsigned char *inbuf;
+};
+
+/* Load input buffer, assumed to be empty, and return bytes loaded and a
+   pointer to them.  read() is called until the buffer is full, or until it
+   returns end-of-file or error.  Return 0 on error. */
+local unsigned in(void *in_desc, unsigned char **buf)
+{
+    int ret;
+    unsigned len;
+    unsigned char *next;
+    struct ind *me = (struct ind *)in_desc;
+
+    next = me->inbuf;
+    *buf = next;
+    len = 0;
+    do {
+        ret = PIECE;
+        if ((unsigned)ret > SIZE - len)
+            ret = (int)(SIZE - len);
+        ret = (int)read(me->infile, next, ret);
+        if (ret == -1) {
+            len = 0;
+            break;
+        }
+        next += ret;
+        len += ret;
+    } while (ret != 0 && len < SIZE);
+    return len;
+}
+
+/* structure for infback() to pass to output function out() -- it maintains the
+   output file, a running CRC-32 check on the output and the total number of
+   bytes output, both for checking against the gzip trailer.  (The length in
+   the gzip trailer is stored modulo 2^32, so it's ok if a long is 32 bits and
+   the output is greater than 4 GB.) */
+struct outd {
+    int outfile;
+    int check;                  /* true if checking crc and total */
+    unsigned long crc;
+    unsigned long total;
+};
+
+/* Write output buffer and update the CRC-32 and total bytes written.  write()
+   is called until all of the output is written or an error is encountered.
+   On success out() returns 0.  For a write failure, out() returns 1.  If the
+   output file descriptor is -1, then nothing is written.
+ */
+local int out(void *out_desc, unsigned char *buf, unsigned len)
+{
+    int ret;
+    struct outd *me = (struct outd *)out_desc;
+
+    if (me->check) {
+        me->crc = crc32(me->crc, buf, len);
+        me->total += len;
+    }
+    if (me->outfile != -1)
+        do {
+            ret = PIECE;
+            if ((unsigned)ret > len)
+                ret = (int)len;
+            ret = (int)write(me->outfile, buf, ret);
+            if (ret == -1)
+                return 1;
+            buf += ret;
+            len -= ret;
+        } while (len != 0);
+    return 0;
+}
+
+/* next input byte macro for use inside lunpipe() and gunpipe() */
+#define NEXT() (have ? 0 : (have = in(indp, &next)), \
+                last = have ? (have--, (int)(*next++)) : -1)
+
+/* memory for gunpipe() and lunpipe() --
+   the first 256 entries of prefix[] and suffix[] are never used, could
+   have offset the index, but it's faster to waste the memory */
+unsigned char inbuf[SIZE];              /* input buffer */
+unsigned char outbuf[SIZE];             /* output buffer */
+unsigned short prefix[65536];           /* index to LZW prefix string */
+unsigned char suffix[65536];            /* one-character LZW suffix */
+unsigned char match[65280 + 2];         /* buffer for reversed match or gzip
+                                           32K sliding window */
+
+/* throw out what's left in the current bits byte buffer (this is a vestigial
+   aspect of the compressed data format derived from an implementation that
+   made use of a special VAX machine instruction!) */
+#define FLUSHCODE() \
+    do { \
+        left = 0; \
+        rem = 0; \
+        if (chunk > have) { \
+            chunk -= have; \
+            have = 0; \
+            if (NEXT() == -1) \
+                break; \
+            chunk--; \
+            if (chunk > have) { \
+                chunk = have = 0; \
+                break; \
+            } \
+        } \
+        have -= chunk; \
+        next += chunk; \
+        chunk = 0; \
+    } while (0)
+
+/* Decompress a compress (LZW) file from indp to outfile.  The compress magic
+   header (two bytes) has already been read and verified.  There are have bytes
+   of buffered input at next.  strm is used for passing error information back
+   to gunpipe().
+
+   lunpipe() will return Z_OK on success, Z_BUF_ERROR for an unexpected end of
+   file, read error, or write error (a write error indicated by strm->next_in
+   not equal to Z_NULL), or Z_DATA_ERROR for invalid input.
+ */
+local int lunpipe(unsigned have, unsigned char *next, struct ind *indp,
+                  int outfile, z_stream *strm)
+{
+    int last;                   /* last byte read by NEXT(), or -1 if EOF */
+    int chunk;                  /* bytes left in current chunk */
+    int left;                   /* bits left in rem */
+    unsigned rem;               /* unused bits from input */
+    int bits;                   /* current bits per code */
+    unsigned code;              /* code, table traversal index */
+    unsigned mask;              /* mask for current bits codes */
+    int max;                    /* maximum bits per code for this stream */
+    int flags;                  /* compress flags, then block compress flag */
+    unsigned end;               /* last valid entry in prefix/suffix tables */
+    unsigned temp;              /* current code */
+    unsigned prev;              /* previous code */
+    unsigned final;             /* last character written for previous code */
+    unsigned stack;             /* next position for reversed string */
+    unsigned outcnt;            /* bytes in output buffer */
+    struct outd outd;           /* output structure */
+
+    /* set up output */
+    outd.outfile = outfile;
+    outd.check = 0;
+
+    /* process remainder of compress header -- a flags byte */
+    flags = NEXT();
+    if (last == -1)
+        return Z_BUF_ERROR;
+    if (flags & 0x60) {
+        strm->msg = (char *)"unknown lzw flags set";
+        return Z_DATA_ERROR;
+    }
+    max = flags & 0x1f;
+    if (max < 9 || max > 16) {
+        strm->msg = (char *)"lzw bits out of range";
+        return Z_DATA_ERROR;
+    }
+    if (max == 9)                           /* 9 doesn't really mean 9 */
+        max = 10;
+    flags &= 0x80;                          /* true if block compress */
+
+    /* clear table */
+    bits = 9;
+    mask = 0x1ff;
+    end = flags ? 256 : 255;
+
+    /* set up: get first 9-bit code, which is the first decompressed byte, but
+       don't create a table entry until the next code */
+    if (NEXT() == -1)                       /* no compressed data is ok */
+        return Z_OK;
+    final = prev = (unsigned)last;          /* low 8 bits of code */
+    if (NEXT() == -1)                       /* missing a bit */
+        return Z_BUF_ERROR;
+    if (last & 1) {                         /* code must be < 256 */
+        strm->msg = (char *)"invalid lzw code";
+        return Z_DATA_ERROR;
+    }
+    rem = (unsigned)last >> 1;              /* remaining 7 bits */
+    left = 7;
+    chunk = bits - 2;                       /* 7 bytes left in this chunk */
+    outbuf[0] = (unsigned char)final;       /* write first decompressed byte */
+    outcnt = 1;
+
+    /* decode codes */
+    stack = 0;
+    for (;;) {
+        /* if the table will be full after this, increment the code size */
+        if (end >= mask && bits < max) {
+            FLUSHCODE();
+            bits++;
+            mask <<= 1;
+            mask++;
+        }
+
+        /* get a code of length bits */
+        if (chunk == 0)                     /* decrement chunk modulo bits */
+            chunk = bits;
+        code = rem;                         /* low bits of code */
+        if (NEXT() == -1) {                 /* EOF is end of compressed data */
+            /* write remaining buffered output */
+            if (outcnt && out(&outd, outbuf, outcnt)) {
+                strm->next_in = outbuf;     /* signal write error */
+                return Z_BUF_ERROR;
+            }
+            return Z_OK;
+        }
+        code += (unsigned)last << left;     /* middle (or high) bits of code */
+        left += 8;
+        chunk--;
+        if (bits > left) {                  /* need more bits */
+            if (NEXT() == -1)               /* can't end in middle of code */
+                return Z_BUF_ERROR;
+            code += (unsigned)last << left; /* high bits of code */
+            left += 8;
+            chunk--;
+        }
+        code &= mask;                       /* mask to current code length */
+        left -= bits;                       /* number of unused bits */
+        rem = (unsigned)last >> (8 - left); /* unused bits from last byte */
+
+        /* process clear code (256) */
+        if (code == 256 && flags) {
+            FLUSHCODE();
+            bits = 9;                       /* initialize bits and mask */
+            mask = 0x1ff;
+            end = 255;                      /* empty table */
+            continue;                       /* get next code */
+        }
+
+        /* special code to reuse last match */
+        temp = code;                        /* save the current code */
+        if (code > end) {
+            /* Be picky on the allowed code here, and make sure that the code
+               we drop through (prev) will be a valid index so that random
+               input does not cause an exception.  The code != end + 1 check is
+               empirically derived, and not checked in the original uncompress
+               code.  If this ever causes a problem, that check could be safely
+               removed.  Leaving this check in greatly improves gun's ability
+               to detect random or corrupted input after a compress header.
+               In any case, the prev > end check must be retained. */
+            if (code != end + 1 || prev > end) {
+                strm->msg = (char *)"invalid lzw code";
+                return Z_DATA_ERROR;
+            }
+            match[stack++] = (unsigned char)final;
+            code = prev;
+        }
+
+        /* walk through linked list to generate output in reverse order */
+        while (code >= 256) {
+            match[stack++] = suffix[code];
+            code = prefix[code];
+        }
+        match[stack++] = (unsigned char)code;
+        final = code;
+
+        /* link new table entry */
+        if (end < mask) {
+            end++;
+            prefix[end] = (unsigned short)prev;
+            suffix[end] = (unsigned char)final;
+        }
+
+        /* set previous code for next iteration */
+        prev = temp;
+
+        /* write output in forward order */
+        while (stack > SIZE - outcnt) {
+            while (outcnt < SIZE)
+                outbuf[outcnt++] = match[--stack];
+            if (out(&outd, outbuf, outcnt)) {
+                strm->next_in = outbuf; /* signal write error */
+                return Z_BUF_ERROR;
+            }
+            outcnt = 0;
+        }
+        do {
+            outbuf[outcnt++] = match[--stack];
+        } while (stack);
+
+        /* loop for next code with final and prev as the last match, rem and
+           left provide the first 0..7 bits of the next code, end is the last
+           valid table entry */
+    }
+}
+
+/* Decompress a gzip file from infile to outfile.  strm is assumed to have been
+   successfully initialized with inflateBackInit().  The input file may consist
+   of a series of gzip streams, in which case all of them will be decompressed
+   to the output file.  If outfile is -1, then the gzip stream(s) integrity is
+   checked and nothing is written.
+
+   The return value is a zlib error code: Z_MEM_ERROR if out of memory,
+   Z_DATA_ERROR if the header or the compressed data is invalid, or if the
+   trailer CRC-32 check or length doesn't match, Z_BUF_ERROR if the input ends
+   prematurely or a write error occurs, or Z_ERRNO if junk (not a another gzip
+   stream) follows a valid gzip stream.
+ */
+local int gunpipe(z_stream *strm, int infile, int outfile)
+{
+    int ret, first, last;
+    unsigned have, flags, len;
+    unsigned char *next;
+    struct ind ind, *indp;
+    struct outd outd;
+
+    /* setup input buffer */
+    ind.infile = infile;
+    ind.inbuf = inbuf;
+    indp = &ind;
+
+    /* decompress concatenated gzip streams */
+    have = 0;                               /* no input data read in yet */
+    first = 1;                              /* looking for first gzip header */
+    strm->next_in = Z_NULL;                 /* so Z_BUF_ERROR means EOF */
+    for (;;) {
+        /* look for the two magic header bytes for a gzip stream */
+        if (NEXT() == -1) {
+            ret = Z_OK;
+            break;                          /* empty gzip stream is ok */
+        }
+        if (last != 31 || (NEXT() != 139 && last != 157)) {
+            strm->msg = (char *)"incorrect header check";
+            ret = first ? Z_DATA_ERROR : Z_ERRNO;
+            break;                          /* not a gzip or compress header */
+        }
+        first = 0;                          /* next non-header is junk */
+
+        /* process a compress (LZW) file -- can't be concatenated after this */
+        if (last == 157) {
+            ret = lunpipe(have, next, indp, outfile, strm);
+            break;
+        }
+
+        /* process remainder of gzip header */
+        ret = Z_BUF_ERROR;
+        if (NEXT() != 8) {                  /* only deflate method allowed */
+            if (last == -1) break;
+            strm->msg = (char *)"unknown compression method";
+            ret = Z_DATA_ERROR;
+            break;
+        }
+        flags = NEXT();                     /* header flags */
+        NEXT();                             /* discard mod time, xflgs, os */
+        NEXT();
+        NEXT();
+        NEXT();
+        NEXT();
+        NEXT();
+        if (last == -1) break;
+        if (flags & 0xe0) {
+            strm->msg = (char *)"unknown header flags set";
+            ret = Z_DATA_ERROR;
+            break;
+        }
+        if (flags & 4) {                    /* extra field */
+            len = NEXT();
+            len += (unsigned)(NEXT()) << 8;
+            if (last == -1) break;
+            while (len > have) {
+                len -= have;
+                have = 0;
+                if (NEXT() == -1) break;
+                len--;
+            }
+            if (last == -1) break;
+            have -= len;
+            next += len;
+        }
+        if (flags & 8)                      /* file name */
+            while (NEXT() != 0 && last != -1)
+                ;
+        if (flags & 16)                     /* comment */
+            while (NEXT() != 0 && last != -1)
+                ;
+        if (flags & 2) {                    /* header crc */
+            NEXT();
+            NEXT();
+        }
+        if (last == -1) break;
+
+        /* set up output */
+        outd.outfile = outfile;
+        outd.check = 1;
+        outd.crc = crc32(0L, Z_NULL, 0);
+        outd.total = 0;
+
+        /* decompress data to output */
+        strm->next_in = next;
+        strm->avail_in = have;
+        ret = inflateBack(strm, in, indp, out, &outd);
+        if (ret != Z_STREAM_END) break;
+        next = strm->next_in;
+        have = strm->avail_in;
+        strm->next_in = Z_NULL;             /* so Z_BUF_ERROR means EOF */
+
+        /* check trailer */
+        ret = Z_BUF_ERROR;
+        if (NEXT() != (outd.crc & 0xff) ||
+            NEXT() != ((outd.crc >> 8) & 0xff) ||
+            NEXT() != ((outd.crc >> 16) & 0xff) ||
+            NEXT() != ((outd.crc >> 24) & 0xff)) {
+            /* crc error */
+            if (last != -1) {
+                strm->msg = (char *)"incorrect data check";
+                ret = Z_DATA_ERROR;
+            }
+            break;
+        }
+        if (NEXT() != (outd.total & 0xff) ||
+            NEXT() != ((outd.total >> 8) & 0xff) ||
+            NEXT() != ((outd.total >> 16) & 0xff) ||
+            NEXT() != ((outd.total >> 24) & 0xff)) {
+            /* length error */
+            if (last != -1) {
+                strm->msg = (char *)"incorrect length check";
+                ret = Z_DATA_ERROR;
+            }
+            break;
+        }
+
+        /* go back and look for another gzip stream */
+    }
+
+    /* clean up and return */
+    return ret;
+}
+
+/* Copy file attributes, from -> to, as best we can.  This is best effort, so
+   no errors are reported.  The mode bits, including suid, sgid, and the sticky
+   bit are copied (if allowed), the owner's user id and group id are copied
+   (again if allowed), and the access and modify times are copied. */
+local void copymeta(char *from, char *to)
+{
+    struct stat was;
+    struct utimbuf when;
+
+    /* get all of from's Unix meta data, return if not a regular file */
+    if (stat(from, &was) != 0 || (was.st_mode & S_IFMT) != S_IFREG)
+        return;
+
+    /* set to's mode bits, ignore errors */
+    (void)chmod(to, was.st_mode & 07777);
+
+    /* copy owner's user and group, ignore errors */
+    (void)chown(to, was.st_uid, was.st_gid);
+
+    /* copy access and modify times, ignore errors */
+    when.actime = was.st_atime;
+    when.modtime = was.st_mtime;
+    (void)utime(to, &when);
+}
+
+/* Decompress the file inname to the file outnname, of if test is true, just
+   decompress without writing and check the gzip trailer for integrity.  If
+   inname is NULL or an empty string, read from stdin.  If outname is NULL or
+   an empty string, write to stdout.  strm is a pre-initialized inflateBack
+   structure.  When appropriate, copy the file attributes from inname to
+   outname.
+
+   gunzip() returns 1 if there is an out-of-memory error or an unexpected
+   return code from gunpipe().  Otherwise it returns 0.
+ */
+local int gunzip(z_stream *strm, char *inname, char *outname, int test)
+{
+    int ret;
+    int infile, outfile;
+
+    /* open files */
+    if (inname == NULL || *inname == 0) {
+        inname = "-";
+        infile = 0;     /* stdin */
+    }
+    else {
+        infile = open(inname, O_RDONLY, 0);
+        if (infile == -1) {
+            fprintf(stderr, "gun cannot open %s\n", inname);
+            return 0;
+        }
+    }
+    if (test)
+        outfile = -1;
+    else if (outname == NULL || *outname == 0) {
+        outname = "-";
+        outfile = 1;    /* stdout */
+    }
+    else {
+        outfile = open(outname, O_CREAT | O_TRUNC | O_WRONLY, 0666);
+        if (outfile == -1) {
+            close(infile);
+            fprintf(stderr, "gun cannot create %s\n", outname);
+            return 0;
+        }
+    }
+    errno = 0;
+
+    /* decompress */
+    ret = gunpipe(strm, infile, outfile);
+    if (outfile > 2) close(outfile);
+    if (infile > 2) close(infile);
+
+    /* interpret result */
+    switch (ret) {
+    case Z_OK:
+    case Z_ERRNO:
+        if (infile > 2 && outfile > 2) {
+            copymeta(inname, outname);          /* copy attributes */
+            unlink(inname);
+        }
+        if (ret == Z_ERRNO)
+            fprintf(stderr, "gun warning: trailing garbage ignored in %s\n",
+                    inname);
+        break;
+    case Z_DATA_ERROR:
+        if (outfile > 2) unlink(outname);
+        fprintf(stderr, "gun data error on %s: %s\n", inname, strm->msg);
+        break;
+    case Z_MEM_ERROR:
+        if (outfile > 2) unlink(outname);
+        fprintf(stderr, "gun out of memory error--aborting\n");
+        return 1;
+    case Z_BUF_ERROR:
+        if (outfile > 2) unlink(outname);
+        if (strm->next_in != Z_NULL) {
+            fprintf(stderr, "gun write error on %s: %s\n",
+                    outname, strerror(errno));
+        }
+        else if (errno) {
+            fprintf(stderr, "gun read error on %s: %s\n",
+                    inname, strerror(errno));
+        }
+        else {
+            fprintf(stderr, "gun unexpected end of file on %s\n",
+                    inname);
+        }
+        break;
+    default:
+        if (outfile > 2) unlink(outname);
+        fprintf(stderr, "gun internal error--aborting\n");
+        return 1;
+    }
+    return 0;
+}
+
+/* Process the gun command line arguments.  See the command syntax near the
+   beginning of this source file. */
+int main(int argc, char **argv)
+{
+    int ret, len, test;
+    char *outname;
+    unsigned char *window;
+    z_stream strm;
+
+    /* initialize inflateBack state for repeated use */
+    window = match;                         /* reuse LZW match buffer */
+    strm.zalloc = Z_NULL;
+    strm.zfree = Z_NULL;
+    strm.opaque = Z_NULL;
+    ret = inflateBackInit(&strm, 15, window);
+    if (ret != Z_OK) {
+        fprintf(stderr, "gun out of memory error--aborting\n");
+        return 1;
+    }
+
+    /* decompress each file to the same name with the suffix removed */
+    argc--;
+    argv++;
+    test = 0;
+    if (argc && strcmp(*argv, "-h") == 0) {
+        fprintf(stderr, "gun 1.3 (12 Jun 2005)\n");
+        fprintf(stderr, "Copyright (c) 2005 Mark Adler\n");
+        fprintf(stderr, "usage: gun [-t] [file1.gz [file2.Z ...]]\n");
+        return 0;
+    }
+    if (argc && strcmp(*argv, "-t") == 0) {
+        test = 1;
+        argc--;
+        argv++;
+    }
+    if (argc)
+        do {
+            if (test)
+                outname = NULL;
+            else {
+                len = (int)strlen(*argv);
+                if (strcmp(*argv + len - 3, ".gz") == 0 ||
+                    strcmp(*argv + len - 3, "-gz") == 0)
+                    len -= 3;
+                else if (strcmp(*argv + len - 2, ".z") == 0 ||
+                    strcmp(*argv + len - 2, "-z") == 0 ||
+                    strcmp(*argv + len - 2, "_z") == 0 ||
+                    strcmp(*argv + len - 2, ".Z") == 0)
+                    len -= 2;
+                else {
+                    fprintf(stderr, "gun error: no gz type on %s--skipping\n",
+                            *argv);
+                    continue;
+                }
+                outname = malloc(len + 1);
+                if (outname == NULL) {
+                    fprintf(stderr, "gun out of memory error--aborting\n");
+                    ret = 1;
+                    break;
+                }
+                memcpy(outname, *argv, len);
+                outname[len] = 0;
+            }
+            ret = gunzip(&strm, *argv, outname, test);
+            if (outname != NULL) free(outname);
+            if (ret) break;
+        } while (argv++, --argc);
+    else
+        ret = gunzip(&strm, NULL, NULL, test);
+
+    /* clean up */
+    inflateBackEnd(&strm);
+    return ret;
+}
diff --git a/gs/zlib/examples/gzappend.c b/gs/zlib/examples/gzappend.c
new file mode 100644
index 000000000..e9e878e11
--- /dev/null
+++ b/gs/zlib/examples/gzappend.c
@@ -0,0 +1,500 @@
+/* gzappend -- command to append to a gzip file
+
+  Copyright (C) 2003 Mark Adler, all rights reserved
+  version 1.1, 4 Nov 2003
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the author be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+
+  Mark Adler    madler@alumni.caltech.edu
+ */
+
+/*
+ * Change history:
+ *
+ * 1.0  19 Oct 2003     - First version
+ * 1.1   4 Nov 2003     - Expand and clarify some comments and notes
+ *                      - Add version and copyright to help
+ *                      - Send help to stdout instead of stderr
+ *                      - Add some preemptive typecasts
+ *                      - Add L to constants in lseek() calls
+ *                      - Remove some debugging information in error messages
+ *                      - Use new data_type definition for zlib 1.2.1
+ *                      - Simplfy and unify file operations
+ *                      - Finish off gzip file in gztack()
+ *                      - Use deflatePrime() instead of adding empty blocks
+ *                      - Keep gzip file clean on appended file read errors
+ *                      - Use in-place rotate instead of auxiliary buffer
+ *                        (Why you ask?  Because it was fun to write!)
+ */
+
+/*
+   gzappend takes a gzip file and appends to it, compressing files from the
+   command line or data from stdin.  The gzip file is written to directly, to
+   avoid copying that file, in case it's large.  Note that this results in the
+   unfriendly behavior that if gzappend fails, the gzip file is corrupted.
+
+   This program was written to illustrate the use of the new Z_BLOCK option of
+   zlib 1.2.x's inflate() function.  This option returns from inflate() at each
+   block boundary to facilitate locating and modifying the last block bit at
+   the start of the final deflate block.  Also whether using Z_BLOCK or not,
+   another required feature of zlib 1.2.x is that inflate() now provides the
+   number of unusued bits in the last input byte used.  gzappend will not work
+   with versions of zlib earlier than 1.2.1.
+
+   gzappend first decompresses the gzip file internally, discarding all but
+   the last 32K of uncompressed data, and noting the location of the last block
+   bit and the number of unused bits in the last byte of the compressed data.
+   The gzip trailer containing the CRC-32 and length of the uncompressed data
+   is verified.  This trailer will be later overwritten.
+
+   Then the last block bit is cleared by seeking back in the file and rewriting
+   the byte that contains it.  Seeking forward, the last byte of the compressed
+   data is saved along with the number of unused bits to initialize deflate.
+
+   A deflate process is initialized, using the last 32K of the uncompressed
+   data from the gzip file to initialize the dictionary.  If the total
+   uncompressed data was less than 32K, then all of it is used to initialize
+   the dictionary.  The deflate output bit buffer is also initialized with the
+   last bits from the original deflate stream.  From here on, the data to
+   append is simply compressed using deflate, and written to the gzip file.
+   When that is complete, the new CRC-32 and uncompressed length are written
+   as the trailer of the gzip file.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include "zlib.h"
+
+#define local static
+#define LGCHUNK 14
+#define CHUNK (1U << LGCHUNK)
+#define DSIZE 32768U
+
+/* print an error message and terminate with extreme prejudice */
+local void bye(char *msg1, char *msg2)
+{
+    fprintf(stderr, "gzappend error: %s%s\n", msg1, msg2);
+    exit(1);
+}
+
+/* return the greatest common divisor of a and b using Euclid's algorithm,
+   modified to be fast when one argument much greater than the other, and
+   coded to avoid unnecessary swapping */
+local unsigned gcd(unsigned a, unsigned b)
+{
+    unsigned c;
+
+    while (a && b)
+        if (a > b) {
+            c = b;
+            while (a - c >= c)
+                c <<= 1;
+            a -= c;
+        }
+        else {
+            c = a;
+            while (b - c >= c)
+                c <<= 1;
+            b -= c;
+        }
+    return a + b;
+}
+
+/* rotate list[0..len-1] left by rot positions, in place */
+local void rotate(unsigned char *list, unsigned len, unsigned rot)
+{
+    unsigned char tmp;
+    unsigned cycles;
+    unsigned char *start, *last, *to, *from;
+
+    /* normalize rot and handle degenerate cases */
+    if (len < 2) return;
+    if (rot >= len) rot %= len;
+    if (rot == 0) return;
+
+    /* pointer to last entry in list */
+    last = list + (len - 1);
+
+    /* do simple left shift by one */
+    if (rot == 1) {
+        tmp = *list;
+        memcpy(list, list + 1, len - 1);
+        *last = tmp;
+        return;
+    }
+
+    /* do simple right shift by one */
+    if (rot == len - 1) {
+        tmp = *last;
+        memmove(list + 1, list, len - 1);
+        *list = tmp;
+        return;
+    }
+
+    /* otherwise do rotate as a set of cycles in place */
+    cycles = gcd(len, rot);             /* number of cycles */
+    do {
+        start = from = list + cycles;   /* start index is arbitrary */
+        tmp = *from;                    /* save entry to be overwritten */
+        for (;;) {
+            to = from;                  /* next step in cycle */
+            from += rot;                /* go right rot positions */
+            if (from > last) from -= len;   /* (pointer better not wrap) */
+            if (from == start) break;   /* all but one shifted */
+            *to = *from;                /* shift left */
+        }
+        *to = tmp;                      /* complete the circle */
+    } while (--cycles);
+}
+
+/* structure for gzip file read operations */
+typedef struct {
+    int fd;                     /* file descriptor */
+    int size;                   /* 1 << size is bytes in buf */
+    unsigned left;              /* bytes available at next */
+    unsigned char *buf;         /* buffer */
+    unsigned char *next;        /* next byte in buffer */
+    char *name;                 /* file name for error messages */
+} file;
+
+/* reload buffer */
+local int readin(file *in)
+{
+    int len;
+
+    len = read(in->fd, in->buf, 1 << in->size);
+    if (len == -1) bye("error reading ", in->name);
+    in->left = (unsigned)len;
+    in->next = in->buf;
+    return len;
+}
+
+/* read from file in, exit if end-of-file */
+local int readmore(file *in)
+{
+    if (readin(in) == 0) bye("unexpected end of ", in->name);
+    return 0;
+}
+
+#define read1(in) (in->left == 0 ? readmore(in) : 0, \
+                   in->left--, *(in->next)++)
+
+/* skip over n bytes of in */
+local void skip(file *in, unsigned n)
+{
+    unsigned bypass;
+
+    if (n > in->left) {
+        n -= in->left;
+        bypass = n & ~((1U << in->size) - 1);
+        if (bypass) {
+            if (lseek(in->fd, (off_t)bypass, SEEK_CUR) == -1)
+                bye("seeking ", in->name);
+            n -= bypass;
+        }
+        readmore(in);
+        if (n > in->left)
+            bye("unexpected end of ", in->name);
+    }
+    in->left -= n;
+    in->next += n;
+}
+
+/* read a four-byte unsigned integer, little-endian, from in */
+unsigned long read4(file *in)
+{
+    unsigned long val;
+
+    val = read1(in);
+    val += (unsigned)read1(in) << 8;
+    val += (unsigned long)read1(in) << 16;
+    val += (unsigned long)read1(in) << 24;
+    return val;
+}
+
+/* skip over gzip header */
+local void gzheader(file *in)
+{
+    int flags;
+    unsigned n;
+
+    if (read1(in) != 31 || read1(in) != 139) bye(in->name, " not a gzip file");
+    if (read1(in) != 8) bye("unknown compression method in", in->name);
+    flags = read1(in);
+    if (flags & 0xe0) bye("unknown header flags set in", in->name);
+    skip(in, 6);
+    if (flags & 4) {
+        n = read1(in);
+        n += (unsigned)(read1(in)) << 8;
+        skip(in, n);
+    }
+    if (flags & 8) while (read1(in) != 0) ;
+    if (flags & 16) while (read1(in) != 0) ;
+    if (flags & 2) skip(in, 2);
+}
+
+/* decompress gzip file "name", return strm with a deflate stream ready to
+   continue compression of the data in the gzip file, and return a file
+   descriptor pointing to where to write the compressed data -- the deflate
+   stream is initialized to compress using level "level" */
+local int gzscan(char *name, z_stream *strm, int level)
+{
+    int ret, lastbit, left, full;
+    unsigned have;
+    unsigned long crc, tot;
+    unsigned char *window;
+    off_t lastoff, end;
+    file gz;
+
+    /* open gzip file */
+    gz.name = name;
+    gz.fd = open(name, O_RDWR, 0);
+    if (gz.fd == -1) bye("cannot open ", name);
+    gz.buf = malloc(CHUNK);
+    if (gz.buf == NULL) bye("out of memory", "");
+    gz.size = LGCHUNK;
+    gz.left = 0;
+
+    /* skip gzip header */
+    gzheader(&gz);
+
+    /* prepare to decompress */
+    window = malloc(DSIZE);
+    if (window == NULL) bye("out of memory", "");
+    strm->zalloc = Z_NULL;
+    strm->zfree = Z_NULL;
+    strm->opaque = Z_NULL;
+    ret = inflateInit2(strm, -15);
+    if (ret != Z_OK) bye("out of memory", " or library mismatch");
+
+    /* decompress the deflate stream, saving append information */
+    lastbit = 0;
+    lastoff = lseek(gz.fd, 0L, SEEK_CUR) - gz.left;
+    left = 0;
+    strm->avail_in = gz.left;
+    strm->next_in = gz.next;
+    crc = crc32(0L, Z_NULL, 0);
+    have = full = 0;
+    do {
+        /* if needed, get more input */
+        if (strm->avail_in == 0) {
+            readmore(&gz);
+            strm->avail_in = gz.left;
+            strm->next_in = gz.next;
+        }
+
+        /* set up output to next available section of sliding window */
+        strm->avail_out = DSIZE - have;
+        strm->next_out = window + have;
+
+        /* inflate and check for errors */
+        ret = inflate(strm, Z_BLOCK);
+        if (ret == Z_STREAM_ERROR) bye("internal stream error!", "");
+        if (ret == Z_MEM_ERROR) bye("out of memory", "");
+        if (ret == Z_DATA_ERROR)
+            bye("invalid compressed data--format violated in", name);
+
+        /* update crc and sliding window pointer */
+        crc = crc32(crc, window + have, DSIZE - have - strm->avail_out);
+        if (strm->avail_out)
+            have = DSIZE - strm->avail_out;
+        else {
+            have = 0;
+            full = 1;
+        }
+
+        /* process end of block */
+        if (strm->data_type & 128) {
+            if (strm->data_type & 64)
+                left = strm->data_type & 0x1f;
+            else {
+                lastbit = strm->data_type & 0x1f;
+                lastoff = lseek(gz.fd, 0L, SEEK_CUR) - strm->avail_in;
+            }
+        }
+    } while (ret != Z_STREAM_END);
+    inflateEnd(strm);
+    gz.left = strm->avail_in;
+    gz.next = strm->next_in;
+
+    /* save the location of the end of the compressed data */
+    end = lseek(gz.fd, 0L, SEEK_CUR) - gz.left;
+
+    /* check gzip trailer and save total for deflate */
+    if (crc != read4(&gz))
+        bye("invalid compressed data--crc mismatch in ", name);
+    tot = strm->total_out;
+    if ((tot & 0xffffffffUL) != read4(&gz))
+        bye("invalid compressed data--length mismatch in", name);
+
+    /* if not at end of file, warn */
+    if (gz.left || readin(&gz))
+        fprintf(stderr,
+            "gzappend warning: junk at end of gzip file overwritten\n");
+
+    /* clear last block bit */
+    lseek(gz.fd, lastoff - (lastbit != 0), SEEK_SET);
+    if (read(gz.fd, gz.buf, 1) != 1) bye("reading after seek on ", name);
+    *gz.buf = (unsigned char)(*gz.buf ^ (1 << ((8 - lastbit) & 7)));
+    lseek(gz.fd, -1L, SEEK_CUR);
+    if (write(gz.fd, gz.buf, 1) != 1) bye("writing after seek to ", name);
+
+    /* if window wrapped, build dictionary from window by rotating */
+    if (full) {
+        rotate(window, DSIZE, have);
+        have = DSIZE;
+    }
+
+    /* set up deflate stream with window, crc, total_in, and leftover bits */
+    ret = deflateInit2(strm, level, Z_DEFLATED, -15, 8, Z_DEFAULT_STRATEGY);
+    if (ret != Z_OK) bye("out of memory", "");
+    deflateSetDictionary(strm, window, have);
+    strm->adler = crc;
+    strm->total_in = tot;
+    if (left) {
+        lseek(gz.fd, --end, SEEK_SET);
+        if (read(gz.fd, gz.buf, 1) != 1) bye("reading after seek on ", name);
+        deflatePrime(strm, 8 - left, *gz.buf);
+    }
+    lseek(gz.fd, end, SEEK_SET);
+
+    /* clean up and return */
+    free(window);
+    free(gz.buf);
+    return gz.fd;
+}
+
+/* append file "name" to gzip file gd using deflate stream strm -- if last
+   is true, then finish off the deflate stream at the end */
+local void gztack(char *name, int gd, z_stream *strm, int last)
+{
+    int fd, len, ret;
+    unsigned left;
+    unsigned char *in, *out;
+
+    /* open file to compress and append */
+    fd = 0;
+    if (name != NULL) {
+        fd = open(name, O_RDONLY, 0);
+        if (fd == -1)
+            fprintf(stderr, "gzappend warning: %s not found, skipping ...\n",
+                    name);
+    }
+
+    /* allocate buffers */
+    in = fd == -1 ? NULL : malloc(CHUNK);
+    out = malloc(CHUNK);
+    if (out == NULL) bye("out of memory", "");
+
+    /* compress input file and append to gzip file */
+    do {
+        /* get more input */
+        len = fd == -1 ? 0 : read(fd, in, CHUNK);
+        if (len == -1) {
+            fprintf(stderr,
+                    "gzappend warning: error reading %s, skipping rest ...\n",
+                    name);
+            len = 0;
+        }
+        strm->avail_in = (unsigned)len;
+        strm->next_in = in;
+        if (len) strm->adler = crc32(strm->adler, in, (unsigned)len);
+
+        /* compress and write all available output */
+        do {
+            strm->avail_out = CHUNK;
+            strm->next_out = out;
+            ret = deflate(strm, last && len == 0 ? Z_FINISH : Z_NO_FLUSH);
+            left = CHUNK - strm->avail_out;
+            while (left) {
+                len = write(gd, out + CHUNK - strm->avail_out - left, left);
+                if (len == -1) bye("writing gzip file", "");
+                left -= (unsigned)len;
+            }
+        } while (strm->avail_out == 0 && ret != Z_STREAM_END);
+    } while (len != 0);
+
+    /* write trailer after last entry */
+    if (last) {
+        deflateEnd(strm);
+        out[0] = (unsigned char)(strm->adler);
+        out[1] = (unsigned char)(strm->adler >> 8);
+        out[2] = (unsigned char)(strm->adler >> 16);
+        out[3] = (unsigned char)(strm->adler >> 24);
+        out[4] = (unsigned char)(strm->total_in);
+        out[5] = (unsigned char)(strm->total_in >> 8);
+        out[6] = (unsigned char)(strm->total_in >> 16);
+        out[7] = (unsigned char)(strm->total_in >> 24);
+        len = 8;
+        do {
+            ret = write(gd, out + 8 - len, len);
+            if (ret == -1) bye("writing gzip file", "");
+            len -= ret;
+        } while (len);
+        close(gd);
+    }
+
+    /* clean up and return */
+    free(out);
+    if (in != NULL) free(in);
+    if (fd > 0) close(fd);
+}
+
+/* process the compression level option if present, scan the gzip file, and
+   append the specified files, or append the data from stdin if no other file
+   names are provided on the command line -- the gzip file must be writable
+   and seekable */
+int main(int argc, char **argv)
+{
+    int gd, level;
+    z_stream strm;
+
+    /* ignore command name */
+    argv++;
+
+    /* provide usage if no arguments */
+    if (*argv == NULL) {
+        printf("gzappend 1.1 (4 Nov 2003) Copyright (C) 2003 Mark Adler\n");
+        printf(
+            "usage: gzappend [-level] file.gz [ addthis [ andthis ... ]]\n");
+        return 0;
+    }
+
+    /* set compression level */
+    level = Z_DEFAULT_COMPRESSION;
+    if (argv[0][0] == '-') {
+        if (argv[0][1] < '0' || argv[0][1] > '9' || argv[0][2] != 0)
+            bye("invalid compression level", "");
+        level = argv[0][1] - '0';
+        if (*++argv == NULL) bye("no gzip file name after options", "");
+    }
+
+    /* prepare to append to gzip file */
+    gd = gzscan(*argv++, &strm, level);
+
+    /* append files on command line, or from stdin if none */
+    if (*argv == NULL)
+        gztack(NULL, gd, &strm, 1);
+    else
+        do {
+            gztack(*argv, gd, &strm, argv[1] == NULL);
+        } while (*++argv != NULL);
+    return 0;
+}
diff --git a/gs/zlib/examples/gzjoin.c b/gs/zlib/examples/gzjoin.c
new file mode 100644
index 000000000..129347ce3
--- /dev/null
+++ b/gs/zlib/examples/gzjoin.c
@@ -0,0 +1,448 @@
+/* gzjoin -- command to join gzip files into one gzip file
+
+  Copyright (C) 2004 Mark Adler, all rights reserved
+  version 1.0, 11 Dec 2004
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the author be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+
+  Mark Adler    madler@alumni.caltech.edu
+ */
+
+/*
+ * Change history:
+ *
+ * 1.0  11 Dec 2004     - First version
+ * 1.1  12 Jun 2005     - Changed ssize_t to long for portability
+ */
+
+/*
+   gzjoin takes one or more gzip files on the command line and writes out a
+   single gzip file that will uncompress to the concatenation of the
+   uncompressed data from the individual gzip files.  gzjoin does this without
+   having to recompress any of the data and without having to calculate a new
+   crc32 for the concatenated uncompressed data.  gzjoin does however have to
+   decompress all of the input data in order to find the bits in the compressed
+   data that need to be modified to concatenate the streams.
+
+   gzjoin does not do an integrity check on the input gzip files other than
+   checking the gzip header and decompressing the compressed data.  They are
+   otherwise assumed to be complete and correct.
+
+   Each joint between gzip files removes at least 18 bytes of previous trailer
+   and subsequent header, and inserts an average of about three bytes to the
+   compressed data in order to connect the streams.  The output gzip file
+   has a minimal ten-byte gzip header with no file name or modification time.
+
+   This program was written to illustrate the use of the Z_BLOCK option of
+   inflate() and the crc32_combine() function.  gzjoin will not compile with
+   versions of zlib earlier than 1.2.3.
+ */
+
+#include <stdio.h>      /* fputs(), fprintf(), fwrite(), putc() */
+#include <stdlib.h>     /* exit(), malloc(), free() */
+#include <fcntl.h>      /* open() */
+#include <unistd.h>     /* close(), read(), lseek() */
+#include "zlib.h"
+    /* crc32(), crc32_combine(), inflateInit2(), inflate(), inflateEnd() */
+
+#define local static
+
+/* exit with an error (return a value to allow use in an expression) */
+local int bail(char *why1, char *why2)
+{
+    fprintf(stderr, "gzjoin error: %s%s, output incomplete\n", why1, why2);
+    exit(1);
+    return 0;
+}
+
+/* -- simple buffered file input with access to the buffer -- */
+
+#define CHUNK 32768         /* must be a power of two and fit in unsigned */
+
+/* bin buffered input file type */
+typedef struct {
+    char *name;             /* name of file for error messages */
+    int fd;                 /* file descriptor */
+    unsigned left;          /* bytes remaining at next */
+    unsigned char *next;    /* next byte to read */
+    unsigned char *buf;     /* allocated buffer of length CHUNK */
+} bin;
+
+/* close a buffered file and free allocated memory */
+local void bclose(bin *in)
+{
+    if (in != NULL) {
+        if (in->fd != -1)
+            close(in->fd);
+        if (in->buf != NULL)
+            free(in->buf);
+        free(in);
+    }
+}
+
+/* open a buffered file for input, return a pointer to type bin, or NULL on
+   failure */
+local bin *bopen(char *name)
+{
+    bin *in;
+
+    in = malloc(sizeof(bin));
+    if (in == NULL)
+        return NULL;
+    in->buf = malloc(CHUNK);
+    in->fd = open(name, O_RDONLY, 0);
+    if (in->buf == NULL || in->fd == -1) {
+        bclose(in);
+        return NULL;
+    }
+    in->left = 0;
+    in->next = in->buf;
+    in->name = name;
+    return in;
+}
+
+/* load buffer from file, return -1 on read error, 0 or 1 on success, with
+   1 indicating that end-of-file was reached */
+local int bload(bin *in)
+{
+    long len;
+
+    if (in == NULL)
+        return -1;
+    if (in->left != 0)
+        return 0;
+    in->next = in->buf;
+    do {
+        len = (long)read(in->fd, in->buf + in->left, CHUNK - in->left);
+        if (len < 0)
+            return -1;
+        in->left += (unsigned)len;
+    } while (len != 0 && in->left < CHUNK);
+    return len == 0 ? 1 : 0;
+}
+
+/* get a byte from the file, bail if end of file */
+#define bget(in) (in->left ? 0 : bload(in), \
+                  in->left ? (in->left--, *(in->next)++) : \
+                    bail("unexpected end of file on ", in->name))
+
+/* get a four-byte little-endian unsigned integer from file */
+local unsigned long bget4(bin *in)
+{
+    unsigned long val;
+
+    val = bget(in);
+    val += (unsigned long)(bget(in)) << 8;
+    val += (unsigned long)(bget(in)) << 16;
+    val += (unsigned long)(bget(in)) << 24;
+    return val;
+}
+
+/* skip bytes in file */
+local void bskip(bin *in, unsigned skip)
+{
+    /* check pointer */
+    if (in == NULL)
+        return;
+
+    /* easy case -- skip bytes in buffer */
+    if (skip <= in->left) {
+        in->left -= skip;
+        in->next += skip;
+        return;
+    }
+
+    /* skip what's in buffer, discard buffer contents */
+    skip -= in->left;
+    in->left = 0;
+
+    /* seek past multiples of CHUNK bytes */
+    if (skip > CHUNK) {
+        unsigned left;
+
+        left = skip & (CHUNK - 1);
+        if (left == 0) {
+            /* exact number of chunks: seek all the way minus one byte to check
+               for end-of-file with a read */
+            lseek(in->fd, skip - 1, SEEK_CUR);
+            if (read(in->fd, in->buf, 1) != 1)
+                bail("unexpected end of file on ", in->name);
+            return;
+        }
+
+        /* skip the integral chunks, update skip with remainder */
+        lseek(in->fd, skip - left, SEEK_CUR);
+        skip = left;
+    }
+
+    /* read more input and skip remainder */
+    bload(in);
+    if (skip > in->left)
+        bail("unexpected end of file on ", in->name);
+    in->left -= skip;
+    in->next += skip;
+}
+
+/* -- end of buffered input functions -- */
+
+/* skip the gzip header from file in */
+local void gzhead(bin *in)
+{
+    int flags;
+
+    /* verify gzip magic header and compression method */
+    if (bget(in) != 0x1f || bget(in) != 0x8b || bget(in) != 8)
+        bail(in->name, " is not a valid gzip file");
+
+    /* get and verify flags */
+    flags = bget(in);
+    if ((flags & 0xe0) != 0)
+        bail("unknown reserved bits set in ", in->name);
+
+    /* skip modification time, extra flags, and os */
+    bskip(in, 6);
+
+    /* skip extra field if present */
+    if (flags & 4) {
+        unsigned len;
+
+        len = bget(in);
+        len += (unsigned)(bget(in)) << 8;
+        bskip(in, len);
+    }
+
+    /* skip file name if present */
+    if (flags & 8)
+        while (bget(in) != 0)
+            ;
+
+    /* skip comment if present */
+    if (flags & 16)
+        while (bget(in) != 0)
+            ;
+
+    /* skip header crc if present */
+    if (flags & 2)
+        bskip(in, 2);
+}
+
+/* write a four-byte little-endian unsigned integer to out */
+local void put4(unsigned long val, FILE *out)
+{
+    putc(val & 0xff, out);
+    putc((val >> 8) & 0xff, out);
+    putc((val >> 16) & 0xff, out);
+    putc((val >> 24) & 0xff, out);
+}
+
+/* Load up zlib stream from buffered input, bail if end of file */
+local void zpull(z_streamp strm, bin *in)
+{
+    if (in->left == 0)
+        bload(in);
+    if (in->left == 0)
+        bail("unexpected end of file on ", in->name);
+    strm->avail_in = in->left;
+    strm->next_in = in->next;
+}
+
+/* Write header for gzip file to out and initialize trailer. */
+local void gzinit(unsigned long *crc, unsigned long *tot, FILE *out)
+{
+    fwrite("\x1f\x8b\x08\0\0\0\0\0\0\xff", 1, 10, out);
+    *crc = crc32(0L, Z_NULL, 0);
+    *tot = 0;
+}
+
+/* Copy the compressed data from name, zeroing the last block bit of the last
+   block if clr is true, and adding empty blocks as needed to get to a byte
+   boundary.  If clr is false, then the last block becomes the last block of
+   the output, and the gzip trailer is written.  crc and tot maintains the
+   crc and length (modulo 2^32) of the output for the trailer.  The resulting
+   gzip file is written to out.  gzinit() must be called before the first call
+   of gzcopy() to write the gzip header and to initialize crc and tot. */
+local void gzcopy(char *name, int clr, unsigned long *crc, unsigned long *tot,
+                  FILE *out)
+{
+    int ret;                /* return value from zlib functions */
+    int pos;                /* where the "last block" bit is in byte */
+    int last;               /* true if processing the last block */
+    bin *in;                /* buffered input file */
+    unsigned char *start;   /* start of compressed data in buffer */
+    unsigned char *junk;    /* buffer for uncompressed data -- discarded */
+    z_off_t len;            /* length of uncompressed data (support > 4 GB) */
+    z_stream strm;          /* zlib inflate stream */
+
+    /* open gzip file and skip header */
+    in = bopen(name);
+    if (in == NULL)
+        bail("could not open ", name);
+    gzhead(in);
+
+    /* allocate buffer for uncompressed data and initialize raw inflate
+       stream */
+    junk = malloc(CHUNK);
+    strm.zalloc = Z_NULL;
+    strm.zfree = Z_NULL;
+    strm.opaque = Z_NULL;
+    strm.avail_in = 0;
+    strm.next_in = Z_NULL;
+    ret = inflateInit2(&strm, -15);
+    if (junk == NULL || ret != Z_OK)
+        bail("out of memory", "");
+
+    /* inflate and copy compressed data, clear last-block bit if requested */
+    len = 0;
+    zpull(&strm, in);
+    start = strm.next_in;
+    last = start[0] & 1;
+    if (last && clr)
+        start[0] &= ~1;
+    strm.avail_out = 0;
+    for (;;) {
+        /* if input used and output done, write used input and get more */
+        if (strm.avail_in == 0 && strm.avail_out != 0) {
+            fwrite(start, 1, strm.next_in - start, out);
+            start = in->buf;
+            in->left = 0;
+            zpull(&strm, in);
+        }
+
+        /* decompress -- return early when end-of-block reached */
+        strm.avail_out = CHUNK;
+        strm.next_out = junk;
+        ret = inflate(&strm, Z_BLOCK);
+        switch (ret) {
+        case Z_MEM_ERROR:
+            bail("out of memory", "");
+        case Z_DATA_ERROR:
+            bail("invalid compressed data in ", in->name);
+        }
+
+        /* update length of uncompressed data */
+        len += CHUNK - strm.avail_out;
+
+        /* check for block boundary (only get this when block copied out) */
+        if (strm.data_type & 128) {
+            /* if that was the last block, then done */
+            if (last)
+                break;
+
+            /* number of unused bits in last byte */
+            pos = strm.data_type & 7;
+
+            /* find the next last-block bit */
+            if (pos != 0) {
+                /* next last-block bit is in last used byte */
+                pos = 0x100 >> pos;
+                last = strm.next_in[-1] & pos;
+                if (last && clr)
+                    strm.next_in[-1] &= ~pos;
+            }
+            else {
+                /* next last-block bit is in next unused byte */
+                if (strm.avail_in == 0) {
+                    /* don't have that byte yet -- get it */
+                    fwrite(start, 1, strm.next_in - start, out);
+                    start = in->buf;
+                    in->left = 0;
+                    zpull(&strm, in);
+                }
+                last = strm.next_in[0] & 1;
+                if (last && clr)
+                    strm.next_in[0] &= ~1;
+            }
+        }
+    }
+
+    /* update buffer with unused input */
+    in->left = strm.avail_in;
+    in->next = strm.next_in;
+
+    /* copy used input, write empty blocks to get to byte boundary */
+    pos = strm.data_type & 7;
+    fwrite(start, 1, in->next - start - 1, out);
+    last = in->next[-1];
+    if (pos == 0 || !clr)
+        /* already at byte boundary, or last file: write last byte */
+        putc(last, out);
+    else {
+        /* append empty blocks to last byte */
+        last &= ((0x100 >> pos) - 1);       /* assure unused bits are zero */
+        if (pos & 1) {
+            /* odd -- append an empty stored block */
+            putc(last, out);
+            if (pos == 1)
+                putc(0, out);               /* two more bits in block header */
+            fwrite("\0\0\xff\xff", 1, 4, out);
+        }
+        else {
+            /* even -- append 1, 2, or 3 empty fixed blocks */
+            switch (pos) {
+            case 6:
+                putc(last | 8, out);
+                last = 0;
+            case 4:
+                putc(last | 0x20, out);
+                last = 0;
+            case 2:
+                putc(last | 0x80, out);
+                putc(0, out);
+            }
+        }
+    }
+
+    /* update crc and tot */
+    *crc = crc32_combine(*crc, bget4(in), len);
+    *tot += (unsigned long)len;
+
+    /* clean up */
+    inflateEnd(&strm);
+    free(junk);
+    bclose(in);
+
+    /* write trailer if this is the last gzip file */
+    if (!clr) {
+        put4(*crc, out);
+        put4(*tot, out);
+    }
+}
+
+/* join the gzip files on the command line, write result to stdout */
+int main(int argc, char **argv)
+{
+    unsigned long crc, tot;     /* running crc and total uncompressed length */
+
+    /* skip command name */
+    argc--;
+    argv++;
+
+    /* show usage if no arguments */
+    if (argc == 0) {
+        fputs("gzjoin usage: gzjoin f1.gz [f2.gz [f3.gz ...]] > fjoin.gz\n",
+              stderr);
+        return 0;
+    }
+
+    /* join gzip files on command line and write to stdout */
+    gzinit(&crc, &tot, stdout);
+    while (argc--)
+        gzcopy(*argv++, argc, &crc, &tot, stdout);
+
+    /* done */
+    return 0;
+}
diff --git a/gs/zlib/examples/gzlog.c b/gs/zlib/examples/gzlog.c
new file mode 100644
index 000000000..f71f817c8
--- /dev/null
+++ b/gs/zlib/examples/gzlog.c
@@ -0,0 +1,413 @@
+/*
+ * gzlog.c
+ * Copyright (C) 2004 Mark Adler
+ * For conditions of distribution and use, see copyright notice in gzlog.h
+ * version 1.0, 26 Nov 2004
+ *
+ */
+
+#include <string.h>             /* memcmp() */
+#include <stdlib.h>             /* malloc(), free(), NULL */
+#include <sys/types.h>          /* size_t, off_t */
+#include <unistd.h>             /* read(), close(), sleep(), ftruncate(), */
+                                /* lseek() */
+#include <fcntl.h>              /* open() */
+#include <sys/file.h>           /* flock() */
+#include "zlib.h"               /* deflateInit2(), deflate(), deflateEnd() */
+
+#include "gzlog.h"              /* interface */
+#define local static
+
+/* log object structure */
+typedef struct {
+    int id;                 /* object identifier */
+    int fd;                 /* log file descriptor */
+    off_t extra;            /* offset of extra "ap" subfield */
+    off_t mark_off;         /* offset of marked data */
+    off_t last_off;         /* offset of last block */
+    unsigned long crc;      /* uncompressed crc */
+    unsigned long len;      /* uncompressed length (modulo 2^32) */
+    unsigned stored;        /* length of current stored block */
+} gz_log;
+
+#define GZLOGID 19334       /* gz_log object identifier */
+
+#define LOCK_RETRY 1            /* retry lock once a second */
+#define LOCK_PATIENCE 1200      /* try about twenty minutes before forcing */
+
+/* acquire a lock on a file */
+local int lock(int fd)
+{
+    int patience;
+
+    /* try to lock every LOCK_RETRY seconds for LOCK_PATIENCE seconds */
+    patience = LOCK_PATIENCE;
+    do {
+        if (flock(fd, LOCK_EX + LOCK_NB) == 0)
+            return 0;
+        (void)sleep(LOCK_RETRY);
+        patience -= LOCK_RETRY;
+    } while (patience > 0);
+
+    /* we've run out of patience -- give up */
+    return -1;
+}
+
+/* release lock */
+local void unlock(int fd)
+{
+    (void)flock(fd, LOCK_UN);
+}
+
+/* release a log object */
+local void log_clean(gz_log *log)
+{
+    unlock(log->fd);
+    (void)close(log->fd);
+    free(log);
+}
+
+/* read an unsigned long from a byte buffer little-endian */
+local unsigned long make_ulg(unsigned char *buf)
+{
+    int n;
+    unsigned long val;
+
+    val = (unsigned long)(*buf++);
+    for (n = 8; n < 32; n += 8)
+        val += (unsigned long)(*buf++) << n;
+    return val;
+}
+
+/* read an off_t from a byte buffer little-endian */
+local off_t make_off(unsigned char *buf)
+{
+    int n;
+    off_t val;
+
+    val = (off_t)(*buf++);
+    for (n = 8; n < 64; n += 8)
+        val += (off_t)(*buf++) << n;
+    return val;
+}
+
+/* write an unsigned long little-endian to byte buffer */
+local void dice_ulg(unsigned long val, unsigned char *buf)
+{
+    int n;
+
+    for (n = 0; n < 4; n++) {
+        *buf++ = val & 0xff;
+        val >>= 8;
+    }
+}
+
+/* write an off_t little-endian to byte buffer */
+local void dice_off(off_t val, unsigned char *buf)
+{
+    int n;
+
+    for (n = 0; n < 8; n++) {
+        *buf++ = val & 0xff;
+        val >>= 8;
+    }
+}
+
+/* initial, empty gzip file for appending */
+local char empty_gz[] = {
+    0x1f, 0x8b,                 /* magic gzip id */
+    8,                          /* compression method is deflate */
+    4,                          /* there is an extra field */
+    0, 0, 0, 0,                 /* no modification time provided */
+    0, 0xff,                    /* no extra flags, no OS */
+    20, 0, 'a', 'p', 16, 0,     /* extra field with "ap" subfield */
+    32, 0, 0, 0, 0, 0, 0, 0,    /* offset of uncompressed data */
+    32, 0, 0, 0, 0, 0, 0, 0,    /* offset of last block */
+    1, 0, 0, 0xff, 0xff,        /* empty stored block (last) */
+    0, 0, 0, 0,                 /* crc */
+    0, 0, 0, 0                  /* uncompressed length */
+};
+
+/* initialize a log object with locking */
+void *gzlog_open(char *path)
+{
+    unsigned xlen;
+    unsigned char temp[20];
+    unsigned sub_len;
+    int good;
+    gz_log *log;
+
+    /* allocate log structure */
+    log = malloc(sizeof(gz_log));
+    if (log == NULL)
+        return NULL;
+    log->id = GZLOGID;
+
+    /* open file, creating it if necessary, and locking it */
+    log->fd = open(path, O_RDWR | O_CREAT, 0600);
+    if (log->fd < 0) {
+        free(log);
+        return NULL;
+    }
+    if (lock(log->fd)) {
+        close(log->fd);
+        free(log);
+        return NULL;
+    }
+
+    /* if file is empty, write new gzip stream */
+    if (lseek(log->fd, 0, SEEK_END) == 0) {
+        if (write(log->fd, empty_gz, sizeof(empty_gz)) != sizeof(empty_gz)) {
+            log_clean(log);
+            return NULL;
+        }
+    }
+
+    /* check gzip header */
+    (void)lseek(log->fd, 0, SEEK_SET);
+    if (read(log->fd, temp, 12) != 12 || temp[0] != 0x1f ||
+        temp[1] != 0x8b || temp[2] != 8 || (temp[3] & 4) == 0) {
+        log_clean(log);
+        return NULL;
+    }
+
+    /* process extra field to find "ap" sub-field */
+    xlen = temp[10] + (temp[11] << 8);
+    good = 0;
+    while (xlen) {
+        if (xlen < 4 || read(log->fd, temp, 4) != 4)
+            break;
+        sub_len = temp[2];
+        sub_len += temp[3] << 8;
+        xlen -= 4;
+        if (memcmp(temp, "ap", 2) == 0 && sub_len == 16) {
+            good = 1;
+            break;
+        }
+        if (xlen < sub_len)
+            break;
+        (void)lseek(log->fd, sub_len, SEEK_CUR);
+        xlen -= sub_len;
+    }
+    if (!good) {
+        log_clean(log);
+        return NULL;
+    }
+
+    /* read in "ap" sub-field */
+    log->extra = lseek(log->fd, 0, SEEK_CUR);
+    if (read(log->fd, temp, 16) != 16) {
+        log_clean(log);
+        return NULL;
+    }
+    log->mark_off = make_off(temp);
+    log->last_off = make_off(temp + 8);
+
+    /* get crc, length of gzip file */
+    (void)lseek(log->fd, log->last_off, SEEK_SET);
+    if (read(log->fd, temp, 13) != 13 ||
+        memcmp(temp, "\001\000\000\377\377", 5) != 0) {
+        log_clean(log);
+        return NULL;
+    }
+    log->crc = make_ulg(temp + 5);
+    log->len = make_ulg(temp + 9);
+
+    /* set up to write over empty last block */
+    (void)lseek(log->fd, log->last_off + 5, SEEK_SET);
+    log->stored = 0;
+    return (void *)log;
+}
+
+/* maximum amount to put in a stored block before starting a new one */
+#define MAX_BLOCK 16384
+
+/* write a block to a log object */
+int gzlog_write(void *obj, char *data, size_t len)
+{
+    size_t some;
+    unsigned char temp[5];
+    gz_log *log;
+
+    /* check object */
+    log = (gz_log *)obj;
+    if (log == NULL || log->id != GZLOGID)
+        return 1;
+
+    /* write stored blocks until all of the input is written */
+    do {
+        some = MAX_BLOCK - log->stored;
+        if (some > len)
+            some = len;
+        if (write(log->fd, data, some) != some)
+            return 1;
+        log->crc = crc32(log->crc, data, some);
+        log->len += some;
+        len -= some;
+        data += some;
+        log->stored += some;
+
+        /* if the stored block is full, end it and start another */
+        if (log->stored == MAX_BLOCK) {
+            (void)lseek(log->fd, log->last_off, SEEK_SET);
+            temp[0] = 0;
+            dice_ulg(log->stored + ((unsigned long)(~log->stored) << 16),
+                     temp + 1);
+            if (write(log->fd, temp, 5) != 5)
+                return 1;
+            log->last_off = lseek(log->fd, log->stored, SEEK_CUR);
+            (void)lseek(log->fd, 5, SEEK_CUR);
+            log->stored = 0;
+        }
+    } while (len);
+    return 0;
+}
+
+/* recompress the remaining stored deflate data in place */
+local int recomp(gz_log *log)
+{
+    z_stream strm;
+    size_t len, max;
+    unsigned char *in;
+    unsigned char *out;
+    unsigned char temp[16];
+
+    /* allocate space and read it all in (it's around 1 MB) */
+    len = log->last_off - log->mark_off;
+    max = len + (len >> 12) + (len >> 14) + 11;
+    out = malloc(max);
+    if (out == NULL)
+        return 1;
+    in = malloc(len);
+    if (in == NULL) {
+        free(out);
+        return 1;
+    }
+    (void)lseek(log->fd, log->mark_off, SEEK_SET);
+    if (read(log->fd, in, len) != len) {
+        free(in);
+        free(out);
+        return 1;
+    }
+
+    /* recompress in memory, decoding stored data as we go */
+    /* note: this assumes that unsigned is four bytes or more */
+    /*       consider not making that assumption */
+    strm.zalloc = Z_NULL;
+    strm.zfree = Z_NULL;
+    strm.opaque = Z_NULL;
+    if (deflateInit2(&strm, Z_BEST_COMPRESSION, Z_DEFLATED, -15, 8,
+        Z_DEFAULT_STRATEGY) != Z_OK) {
+        free(in);
+        free(out);
+        return 1;
+    }
+    strm.next_in = in;
+    strm.avail_out = max;
+    strm.next_out = out;
+    while (len >= 5) {
+        if (strm.next_in[0] != 0)
+            break;
+        strm.avail_in = strm.next_in[1] + (strm.next_in[2] << 8);
+        strm.next_in += 5;
+        len -= 5;
+        if (strm.avail_in != 0) {
+            if (len < strm.avail_in)
+                break;
+            len -= strm.avail_in;
+            (void)deflate(&strm, Z_NO_FLUSH);
+            if (strm.avail_in != 0 || strm.avail_out == 0)
+                break;
+        }
+    }
+    (void)deflate(&strm, Z_SYNC_FLUSH);
+    (void)deflateEnd(&strm);
+    free(in);
+    if (len != 0 || strm.avail_out == 0) {
+        free(out);
+        return 1;
+    }
+
+    /* overwrite stored data with compressed data */
+    (void)lseek(log->fd, log->mark_off, SEEK_SET);
+    len = max - strm.avail_out;
+    if (write(log->fd, out, len) != len) {
+        free(out);
+        return 1;
+    }
+    free(out);
+
+    /* write last empty block, crc, and length */
+    log->mark_off = log->last_off = lseek(log->fd, 0, SEEK_CUR);
+    temp[0] = 1;
+    dice_ulg(0xffffL << 16, temp + 1);
+    dice_ulg(log->crc, temp + 5);
+    dice_ulg(log->len, temp + 9);
+    if (write(log->fd, temp, 13) != 13)
+        return 1;
+
+    /* truncate file to discard remaining stored data and old trailer */
+    ftruncate(log->fd, lseek(log->fd, 0, SEEK_CUR));
+
+    /* update extra field to point to new last empty block */
+    (void)lseek(log->fd, log->extra, SEEK_SET);
+    dice_off(log->mark_off, temp);
+    dice_off(log->last_off, temp + 8);
+    if (write(log->fd, temp, 16) != 16)
+        return 1;
+    return 0;
+}
+
+/* maximum accumulation of stored blocks before compressing */
+#define MAX_STORED 1048576
+
+/* close log object */
+int gzlog_close(void *obj)
+{
+    unsigned char temp[8];
+    gz_log *log;
+
+    /* check object */
+    log = (gz_log *)obj;
+    if (log == NULL || log->id != GZLOGID)
+        return 1;
+
+    /* go to start of most recent block being written */
+    (void)lseek(log->fd, log->last_off, SEEK_SET);
+
+    /* if some stuff was put there, update block */
+    if (log->stored) {
+        temp[0] = 0;
+        dice_ulg(log->stored + ((unsigned long)(~log->stored) << 16),
+                 temp + 1);
+        if (write(log->fd, temp, 5) != 5)
+            return 1;
+        log->last_off = lseek(log->fd, log->stored, SEEK_CUR);
+    }
+
+    /* write last block (empty) */
+    if (write(log->fd, "\001\000\000\377\377", 5) != 5)
+        return 1;
+
+    /* write updated crc and uncompressed length */
+    dice_ulg(log->crc, temp);
+    dice_ulg(log->len, temp + 4);
+    if (write(log->fd, temp, 8) != 8)
+        return 1;
+
+    /* put offset of that last block in gzip extra block */
+    (void)lseek(log->fd, log->extra + 8, SEEK_SET);
+    dice_off(log->last_off, temp);
+    if (write(log->fd, temp, 8) != 8)
+        return 1;
+
+    /* if more than 1 MB stored, then time to compress it */
+    if (log->last_off - log->mark_off > MAX_STORED) {
+        if (recomp(log))
+            return 1;
+    }
+
+    /* unlock and close file */
+    log_clean(log);
+    return 0;
+}
diff --git a/gs/zlib/examples/gzlog.h b/gs/zlib/examples/gzlog.h
new file mode 100644
index 000000000..a800bd539
--- /dev/null
+++ b/gs/zlib/examples/gzlog.h
@@ -0,0 +1,58 @@
+/* gzlog.h
+  Copyright (C) 2004 Mark Adler, all rights reserved
+  version 1.0, 26 Nov 2004
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the author be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+
+  Mark Adler    madler@alumni.caltech.edu
+ */
+
+/*
+   The gzlog object allows writing short messages to a gzipped log file,
+   opening the log file locked for small bursts, and then closing it.  The log
+   object works by appending stored data to the gzip file until 1 MB has been
+   accumulated.  At that time, the stored data is compressed, and replaces the
+   uncompressed data in the file.  The log file is truncated to its new size at
+   that time.  After closing, the log file is always valid gzip file that can
+   decompressed to recover what was written.
+
+   A gzip header "extra" field contains two file offsets for appending.  The
+   first points to just after the last compressed data.  The second points to
+   the last stored block in the deflate stream, which is empty.  All of the
+   data between those pointers is uncompressed.
+ */
+
+/* Open a gzlog object, creating the log file if it does not exist.  Return
+   NULL on error.  Note that gzlog_open() could take a long time to return if
+   there is difficulty in locking the file. */
+void *gzlog_open(char *path);
+
+/* Write to a gzlog object.  Return non-zero on error.  This function will
+   simply write data to the file uncompressed.  Compression of the data
+   will not occur until gzlog_close() is called.  It is expected that
+   gzlog_write() is used for a short message, and then gzlog_close() is
+   called.  If a large amount of data is to be written, then the application
+   should write no more than 1 MB at a time with gzlog_write() before
+   calling gzlog_close() and then gzlog_open() again. */
+int gzlog_write(void *log, char *data, size_t len);
+
+/* Close a gzlog object.  Return non-zero on error.  The log file is locked
+   until this function is called.  This function will compress stored data
+   at the end of the gzip file if at least 1 MB has been accumulated.  Note
+   that the file will not be a valid gzip file until this function completes.
+ */
+int gzlog_close(void *log);
diff --git a/gs/zlib/examples/zlib_how.html b/gs/zlib/examples/zlib_how.html
new file mode 100644
index 000000000..40998dbf0
--- /dev/null
+++ b/gs/zlib/examples/zlib_how.html
@@ -0,0 +1,523 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
+  "http://www.w3.org/TR/REC-html40/loose.dtd">
+<html>
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
+<title>zlib Usage Example</title>
+<!--  Copyright (c) 2004 Mark Adler.  -->
+</head>
+<body bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#00A000">
+<h2 align="center"> zlib Usage Example </h2>
+We often get questions about how the <tt>deflate()</tt> and <tt>inflate()</tt> functions should be used.
+Users wonder when they should provide more input, when they should use more output,
+what to do with a <tt>Z_BUF_ERROR</tt>, how to make sure the process terminates properly, and
+so on.  So for those who have read <tt>zlib.h</tt> (a few times), and
+would like further edification, below is an annotated example in C of simple routines to compress and decompress
+from an input file to an output file using <tt>deflate()</tt> and <tt>inflate()</tt> respectively.  The
+annotations are interspersed between lines of the code.  So please read between the lines.
+We hope this helps explain some of the intricacies of <em>zlib</em>.
+<p>
+Without further adieu, here is the program <a href="zpipe.c"><tt>zpipe.c</tt></a>:
+<pre><b>
+/* zpipe.c: example of proper use of zlib's inflate() and deflate()
+   Not copyrighted -- provided to the public domain
+   Version 1.2  9 November 2004  Mark Adler */
+
+/* Version history:
+   1.0  30 Oct 2004  First version
+   1.1   8 Nov 2004  Add void casting for unused return values
+                     Use switch statement for inflate() return values
+   1.2   9 Nov 2004  Add assertions to document zlib guarantees
+ */
+</b></pre><!-- -->
+We now include the header files for the required definitions.  From
+<tt>stdio.h</tt> we use <tt>fopen()</tt>, <tt>fread()</tt>, <tt>fwrite()</tt>,
+<tt>feof()</tt>, <tt>ferror()</tt>, and <tt>fclose()</tt> for file i/o, and
+<tt>fputs()</tt> for error messages.  From <tt>string.h</tt> we use
+<tt>strcmp()</tt> for command line argument processing.
+From <tt>assert.h</tt> we use the <tt>assert()</tt> macro.
+From <tt>zlib.h</tt>
+we use the basic compression functions <tt>deflateInit()</tt>,
+<tt>deflate()</tt>, and <tt>deflateEnd()</tt>, and the basic decompression
+functions <tt>inflateInit()</tt>, <tt>inflate()</tt>, and
+<tt>inflateEnd()</tt>.
+<pre><b>
+#include &lt;stdio.h&gt;
+#include &lt;string.h&gt;
+#include &lt;assert.h&gt;
+#include "zlib.h"
+</b></pre><!-- -->
+<tt>CHUNK</tt> is simply the buffer size for feeding data to and pulling data
+from the <em>zlib</em> routines.  Larger buffer sizes would be more efficient,
+especially for <tt>inflate()</tt>.  If the memory is available, buffers sizes
+on the order of 128K or 256K bytes should be used.
+<pre><b>
+#define CHUNK 16384
+</b></pre><!-- -->
+The <tt>def()</tt> routine compresses data from an input file to an output file.  The output data
+will be in the <em>zlib</em> format, which is different from the <em>gzip</em> or <em>zip</em>
+formats.  The <em>zlib</em> format has a very small header of only two bytes to identify it as
+a <em>zlib</em> stream and to provide decoding information, and a four-byte trailer with a fast
+check value to verify the integrity of the uncompressed data after decoding.
+<pre><b>
+/* Compress from file source to file dest until EOF on source.
+   def() returns Z_OK on success, Z_MEM_ERROR if memory could not be
+   allocated for processing, Z_STREAM_ERROR if an invalid compression
+   level is supplied, Z_VERSION_ERROR if the version of zlib.h and the
+   version of the library linked do not match, or Z_ERRNO if there is
+   an error reading or writing the files. */
+int def(FILE *source, FILE *dest, int level)
+{
+</b></pre>
+Here are the local variables for <tt>def()</tt>.  <tt>ret</tt> will be used for <em>zlib</em>
+return codes.  <tt>flush</tt> will keep track of the current flushing state for <tt>deflate()</tt>,
+which is either no flushing, or flush to completion after the end of the input file is reached.
+<tt>have</tt> is the amount of data returned from <tt>deflate()</tt>.  The <tt>strm</tt> structure
+is used to pass information to and from the <em>zlib</em> routines, and to maintain the
+<tt>deflate()</tt> state.  <tt>in</tt> and <tt>out</tt> are the input and output buffers for
+<tt>deflate()</tt>.
+<pre><b>
+    int ret, flush;
+    unsigned have;
+    z_stream strm;
+    char in[CHUNK];
+    char out[CHUNK];
+</b></pre><!-- -->
+The first thing we do is to initialize the <em>zlib</em> state for compression using
+<tt>deflateInit()</tt>.  This must be done before the first use of <tt>deflate()</tt>.
+The <tt>zalloc</tt>, <tt>zfree</tt>, and <tt>opaque</tt> fields in the <tt>strm</tt>
+structure must be initialized before calling <tt>deflateInit()</tt>.  Here they are
+set to the <em>zlib</em> constant <tt>Z_NULL</tt> to request that <em>zlib</em> use
+the default memory allocation routines.  An application may also choose to provide
+custom memory allocation routines here.  <tt>deflateInit()</tt> will allocate on the
+order of 256K bytes for the internal state.
+(See <a href="zlib_tech.html"><em>zlib Technical Details</em></a>.)
+<p>
+<tt>deflateInit()</tt> is called with a pointer to the structure to be initialized and
+the compression level, which is an integer in the range of -1 to 9.  Lower compression
+levels result in faster execution, but less compression.  Higher levels result in
+greater compression, but slower execution.  The <em>zlib</em> constant Z_DEFAULT_COMPRESSION,
+equal to -1,
+provides a good compromise between compression and speed and is equivalent to level 6.
+Level 0 actually does no compression at all, and in fact expands the data slightly to produce
+the <em>zlib</em> format (it is not a byte-for-byte copy of the input).
+More advanced applications of <em>zlib</em>
+may use <tt>deflateInit2()</tt> here instead.  Such an application may want to reduce how
+much memory will be used, at some price in compression.  Or it may need to request a
+<em>gzip</em> header and trailer instead of a <em>zlib</em> header and trailer, or raw
+encoding with no header or trailer at all.
+<p>
+We must check the return value of <tt>deflateInit()</tt> against the <em>zlib</em> constant
+<tt>Z_OK</tt> to make sure that it was able to
+allocate memory for the internal state, and that the provided arguments were valid.
+<tt>deflateInit()</tt> will also check that the version of <em>zlib</em> that the <tt>zlib.h</tt>
+file came from matches the version of <em>zlib</em> actually linked with the program.  This
+is especially important for environments in which <em>zlib</em> is a shared library.
+<p>
+Note that an application can initialize multiple, independent <em>zlib</em> streams, which can
+operate in parallel.  The state information maintained in the structure allows the <em>zlib</em>
+routines to be reentrant.
+<pre><b>
+    /* allocate deflate state */
+    strm.zalloc = Z_NULL;
+    strm.zfree = Z_NULL;
+    strm.opaque = Z_NULL;
+    ret = deflateInit(&amp;strm, level);
+    if (ret != Z_OK)
+        return ret;
+</b></pre><!-- -->
+With the pleasantries out of the way, now we can get down to business.  The outer <tt>do</tt>-loop
+reads all of the input file and exits at the bottom of the loop once end-of-file is reached.
+This loop contains the only call of <tt>deflate()</tt>.  So we must make sure that all of the
+input data has been processed and that all of the output data has been generated and consumed
+before we fall out of the loop at the bottom.
+<pre><b>
+    /* compress until end of file */
+    do {
+</b></pre>
+We start off by reading data from the input file.  The number of bytes read is put directly
+into <tt>avail_in</tt>, and a pointer to those bytes is put into <tt>next_in</tt>.  We also
+check to see if end-of-file on the input has been reached.  If we are at the end of file, then <tt>flush</tt> is set to the
+<em>zlib</em> constant <tt>Z_FINISH</tt>, which is later passed to <tt>deflate()</tt> to
+indicate that this is the last chunk of input data to compress.  We need to use <tt>feof()</tt>
+to check for end-of-file as opposed to seeing if fewer than <tt>CHUNK</tt> bytes have been read.  The
+reason is that if the input file length is an exact multiple of <tt>CHUNK</tt>, we will miss
+the fact that we got to the end-of-file, and not know to tell <tt>deflate()</tt> to finish
+up the compressed stream.  If we are not yet at the end of the input, then the <em>zlib</em>
+constant <tt>Z_NO_FLUSH</tt> will be passed to <tt>deflate</tt> to indicate that we are still
+in the middle of the uncompressed data.
+<p>
+If there is an error in reading from the input file, the process is aborted with
+<tt>deflateEnd()</tt> being called to free the allocated <em>zlib</em> state before returning
+the error.  We wouldn't want a memory leak, now would we?  <tt>deflateEnd()</tt> can be called
+at any time after the state has been initialized.  Once that's done, <tt>deflateInit()</tt> (or
+<tt>deflateInit2()</tt>) would have to be called to start a new compression process.  There is
+no point here in checking the <tt>deflateEnd()</tt> return code.  The deallocation can't fail.
+<pre><b>
+        strm.avail_in = fread(in, 1, CHUNK, source);
+        if (ferror(source)) {
+            (void)deflateEnd(&amp;strm);
+            return Z_ERRNO;
+        }
+        flush = feof(source) ? Z_FINISH : Z_NO_FLUSH;
+        strm.next_in = in;
+</b></pre><!-- -->
+The inner <tt>do</tt>-loop passes our chunk of input data to <tt>deflate()</tt>, and then
+keeps calling <tt>deflate()</tt> until it is done producing output.  Once there is no more
+new output, <tt>deflate()</tt> is guaranteed to have consumed all of the input, i.e.,
+<tt>avail_in</tt> will be zero.
+<pre><b>
+        /* run deflate() on input until output buffer not full, finish
+           compression if all of source has been read in */
+        do {
+</b></pre>
+Output space is provided to <tt>deflate()</tt> by setting <tt>avail_out</tt> to the number
+of available output bytes and <tt>next_out</tt> to a pointer to that space.
+<pre><b>
+            strm.avail_out = CHUNK;
+            strm.next_out = out;
+</b></pre>
+Now we call the compression engine itself, <tt>deflate()</tt>.  It takes as many of the
+<tt>avail_in</tt> bytes at <tt>next_in</tt> as it can process, and writes as many as
+<tt>avail_out</tt> bytes to <tt>next_out</tt>.  Those counters and pointers are then
+updated past the input data consumed and the output data written.  It is the amount of
+output space available that may limit how much input is consumed.
+Hence the inner loop to make sure that
+all of the input is consumed by providing more output space each time.  Since <tt>avail_in</tt>
+and <tt>next_in</tt> are updated by <tt>deflate()</tt>, we don't have to mess with those
+between <tt>deflate()</tt> calls until it's all used up.
+<p>
+The parameters to <tt>deflate()</tt> are a pointer to the <tt>strm</tt> structure containing
+the input and output information and the internal compression engine state, and a parameter
+indicating whether and how to flush data to the output.  Normally <tt>deflate</tt> will consume
+several K bytes of input data before producing any output (except for the header), in order
+to accumulate statistics on the data for optimum compression.  It will then put out a burst of
+compressed data, and proceed to consume more input before the next burst.  Eventually,
+<tt>deflate()</tt>
+must be told to terminate the stream, complete the compression with provided input data, and
+write out the trailer check value.  <tt>deflate()</tt> will continue to compress normally as long
+as the flush parameter is <tt>Z_NO_FLUSH</tt>.  Once the <tt>Z_FINISH</tt> parameter is provided,
+<tt>deflate()</tt> will begin to complete the compressed output stream.  However depending on how
+much output space is provided, <tt>deflate()</tt> may have to be called several times until it
+has provided the complete compressed stream, even after it has consumed all of the input.  The flush
+parameter must continue to be <tt>Z_FINISH</tt> for those subsequent calls.
+<p>
+There are other values of the flush parameter that are used in more advanced applications.  You can
+force <tt>deflate()</tt> to produce a burst of output that encodes all of the input data provided
+so far, even if it wouldn't have otherwise, for example to control data latency on a link with
+compressed data.  You can also ask that <tt>deflate()</tt> do that as well as erase any history up to
+that point so that what follows can be decompressed independently, for example for random access
+applications.  Both requests will degrade compression by an amount depending on how often such
+requests are made.
+<p>
+<tt>deflate()</tt> has a return value that can indicate errors, yet we do not check it here.  Why
+not?  Well, it turns out that <tt>deflate()</tt> can do no wrong here.  Let's go through
+<tt>deflate()</tt>'s return values and dispense with them one by one.  The possible values are
+<tt>Z_OK</tt>, <tt>Z_STREAM_END</tt>, <tt>Z_STREAM_ERROR</tt>, or <tt>Z_BUF_ERROR</tt>.  <tt>Z_OK</tt>
+is, well, ok.  <tt>Z_STREAM_END</tt> is also ok and will be returned for the last call of
+<tt>deflate()</tt>.  This is already guaranteed by calling <tt>deflate()</tt> with <tt>Z_FINISH</tt>
+until it has no more output.  <tt>Z_STREAM_ERROR</tt> is only possible if the stream is not
+initialized properly, but we did initialize it properly.  There is no harm in checking for
+<tt>Z_STREAM_ERROR</tt> here, for example to check for the possibility that some
+other part of the application inadvertently clobbered the memory containing the <em>zlib</em> state.
+<tt>Z_BUF_ERROR</tt> will be explained further below, but
+suffice it to say that this is simply an indication that <tt>deflate()</tt> could not consume
+more input or produce more output.  <tt>deflate()</tt> can be called again with more output space
+or more available input, which it will be in this code.
+<pre><b>
+            ret = deflate(&amp;strm, flush);    /* no bad return value */
+            assert(ret != Z_STREAM_ERROR);  /* state not clobbered */
+</b></pre>
+Now we compute how much output <tt>deflate()</tt> provided on the last call, which is the
+difference between how much space was provided before the call, and how much output space
+is still available after the call.  Then that data, if any, is written to the output file.
+We can then reuse the output buffer for the next call of <tt>deflate()</tt>.  Again if there
+is a file i/o error, we call <tt>deflateEnd()</tt> before returning to avoid a memory leak.
+<pre><b>
+            have = CHUNK - strm.avail_out;
+            if (fwrite(out, 1, have, dest) != have || ferror(dest)) {
+                (void)deflateEnd(&amp;strm);
+                return Z_ERRNO;
+            }
+</b></pre>
+The inner <tt>do</tt>-loop is repeated until the last <tt>deflate()</tt> call fails to fill the
+provided output buffer.  Then we know that <tt>deflate()</tt> has done as much as it can with
+the provided input, and that all of that input has been consumed.  We can then fall out of this
+loop and reuse the input buffer.
+<p>
+The way we tell that <tt>deflate()</tt> has no more output is by seeing that it did not fill
+the output buffer, leaving <tt>avail_out</tt> greater than zero.  However suppose that
+<tt>deflate()</tt> has no more output, but just so happened to exactly fill the output buffer!
+<tt>avail_out</tt> is zero, and we can't tell that <tt>deflate()</tt> has done all it can.
+As far as we know, <tt>deflate()</tt>
+has more output for us.  So we call it again.  But now <tt>deflate()</tt> produces no output
+at all, and <tt>avail_out</tt> remains unchanged as <tt>CHUNK</tt>.  That <tt>deflate()</tt> call
+wasn't able to do anything, either consume input or produce output, and so it returns
+<tt>Z_BUF_ERROR</tt>.  (See, I told you I'd cover this later.)  However this is not a problem at
+all.  Now we finally have the desired indication that <tt>deflate()</tt> is really done,
+and so we drop out of the inner loop to provide more input to <tt>deflate()</tt>.
+<p>
+With <tt>flush</tt> set to <tt>Z_FINISH</tt>, this final set of <tt>deflate()</tt> calls will
+complete the output stream.  Once that is done, subsequent calls of <tt>deflate()</tt> would return
+<tt>Z_STREAM_ERROR</tt> if the flush parameter is not <tt>Z_FINISH</tt>, and do no more processing
+until the state is reinitialized.
+<p>
+Some applications of <em>zlib</em> have two loops that call <tt>deflate()</tt>
+instead of the single inner loop we have here.  The first loop would call
+without flushing and feed all of the data to <tt>deflate()</tt>.  The second loop would call
+<tt>deflate()</tt> with no more
+data and the <tt>Z_FINISH</tt> parameter to complete the process.  As you can see from this
+example, that can be avoided by simply keeping track of the current flush state.
+<pre><b>
+        } while (strm.avail_out == 0);
+        assert(strm.avail_in == 0);     /* all input will be used */
+</b></pre><!-- -->
+Now we check to see if we have already processed all of the input file.  That information was
+saved in the <tt>flush</tt> variable, so we see if that was set to <tt>Z_FINISH</tt>.  If so,
+then we're done and we fall out of the outer loop.  We're guaranteed to get <tt>Z_STREAM_END</tt>
+from the last <tt>deflate()</tt> call, since we ran it until the last chunk of input was
+consumed and all of the output was generated.
+<pre><b>
+        /* done when last data in file processed */
+    } while (flush != Z_FINISH);
+    assert(ret == Z_STREAM_END);        /* stream will be complete */
+</b></pre><!-- -->
+The process is complete, but we still need to deallocate the state to avoid a memory leak
+(or rather more like a memory hemorrhage if you didn't do this).  Then
+finally we can return with a happy return value.
+<pre><b>
+    /* clean up and return */
+    (void)deflateEnd(&amp;strm);
+    return Z_OK;
+}
+</b></pre><!-- -->
+Now we do the same thing for decompression in the <tt>inf()</tt> routine. <tt>inf()</tt>
+decompresses what is hopefully a valid <em>zlib</em> stream from the input file and writes the
+uncompressed data to the output file.  Much of the discussion above for <tt>def()</tt>
+applies to <tt>inf()</tt> as well, so the discussion here will focus on the differences between
+the two.
+<pre><b>
+/* Decompress from file source to file dest until stream ends or EOF.
+   inf() returns Z_OK on success, Z_MEM_ERROR if memory could not be
+   allocated for processing, Z_DATA_ERROR if the deflate data is
+   invalid or incomplete, Z_VERSION_ERROR if the version of zlib.h and
+   the version of the library linked do not match, or Z_ERRNO if there
+   is an error reading or writing the files. */
+int inf(FILE *source, FILE *dest)
+{
+</b></pre>
+The local variables have the same functionality as they do for <tt>def()</tt>.  The
+only difference is that there is no <tt>flush</tt> variable, since <tt>inflate()</tt>
+can tell from the <em>zlib</em> stream itself when the stream is complete.
+<pre><b>
+    int ret;
+    unsigned have;
+    z_stream strm;
+    char in[CHUNK];
+    char out[CHUNK];
+</b></pre><!-- -->
+The initialization of the state is the same, except that there is no compression level,
+of course, and two more elements of the structure are initialized.  <tt>avail_in</tt>
+and <tt>next_in</tt> must be initialized before calling <tt>inflateInit()</tt>.  This
+is because the application has the option to provide the start of the zlib stream in
+order for <tt>inflateInit()</tt> to have access to information about the compression
+method to aid in memory allocation.  In the current implementation of <em>zlib</em>
+(up through versions 1.2.x), the method-dependent memory allocations are deferred to the first call of
+<tt>inflate()</tt> anyway.  However those fields must be initialized since later versions
+of <em>zlib</em> that provide more compression methods may take advantage of this interface.
+In any case, no decompression is performed by <tt>inflateInit()</tt>, so the
+<tt>avail_out</tt> and <tt>next_out</tt> fields do not need to be initialized before calling.
+<p>
+Here <tt>avail_in</tt> is set to zero and <tt>next_in</tt> is set to <tt>Z_NULL</tt> to
+indicate that no input data is being provided.
+<pre><b>
+    /* allocate inflate state */
+    strm.zalloc = Z_NULL;
+    strm.zfree = Z_NULL;
+    strm.opaque = Z_NULL;
+    strm.avail_in = 0;
+    strm.next_in = Z_NULL;
+    ret = inflateInit(&amp;strm);
+    if (ret != Z_OK)
+        return ret;
+</b></pre><!-- -->
+The outer <tt>do</tt>-loop decompresses input until <tt>inflate()</tt> indicates
+that it has reached the end of the compressed data and has produced all of the uncompressed
+output.  This is in contrast to <tt>def()</tt> which processes all of the input file.
+If end-of-file is reached before the compressed data self-terminates, then the compressed
+data is incomplete and an error is returned.
+<pre><b>
+    /* decompress until deflate stream ends or end of file */
+    do {
+</b></pre>
+We read input data and set the <tt>strm</tt> structure accordingly.  If we've reached the
+end of the input file, then we leave the outer loop and report an error, since the
+compressed data is incomplete.  Note that we may read more data than is eventually consumed
+by <tt>inflate()</tt>, if the input file continues past the <em>zlib</em> stream.
+For applications where <em>zlib</em> streams are embedded in other data, this routine would
+need to be modified to return the unused data, or at least indicate how much of the input
+data was not used, so the application would know where to pick up after the <em>zlib</em> stream.
+<pre><b>
+        strm.avail_in = fread(in, 1, CHUNK, source);
+        if (ferror(source)) {
+            (void)inflateEnd(&amp;strm);
+            return Z_ERRNO;
+        }
+        if (strm.avail_in == 0)
+            break;
+        strm.next_in = in;
+</b></pre><!-- -->
+The inner <tt>do</tt>-loop has the same function it did in <tt>def()</tt>, which is to
+keep calling <tt>inflate()</tt> until has generated all of the output it can with the
+provided input.
+<pre><b>
+        /* run inflate() on input until output buffer not full */
+        do {
+</b></pre>
+Just like in <tt>def()</tt>, the same output space is provided for each call of <tt>inflate()</tt>.
+<pre><b>
+            strm.avail_out = CHUNK;
+            strm.next_out = out;
+</b></pre>
+Now we run the decompression engine itself.  There is no need to adjust the flush parameter, since
+the <em>zlib</em> format is self-terminating. The main difference here is that there are
+return values that we need to pay attention to.  <tt>Z_DATA_ERROR</tt>
+indicates that <tt>inflate()</tt> detected an error in the <em>zlib</em> compressed data format,
+which means that either the data is not a <em>zlib</em> stream to begin with, or that the data was
+corrupted somewhere along the way since it was compressed.  The other error to be processed is
+<tt>Z_MEM_ERROR</tt>, which can occur since memory allocation is deferred until <tt>inflate()</tt>
+needs it, unlike <tt>deflate()</tt>, whose memory is allocated at the start by <tt>deflateInit()</tt>.
+<p>
+Advanced applications may use
+<tt>deflateSetDictionary()</tt> to prime <tt>deflate()</tt> with a set of likely data to improve the
+first 32K or so of compression.  This is noted in the <em>zlib</em> header, so <tt>inflate()</tt>
+requests that that dictionary be provided before it can start to decompress.  Without the dictionary,
+correct decompression is not possible.  For this routine, we have no idea what the dictionary is,
+so the <tt>Z_NEED_DICT</tt> indication is converted to a <tt>Z_DATA_ERROR</tt>.
+<p>
+<tt>inflate()</tt> can also return <tt>Z_STREAM_ERROR</tt>, which should not be possible here,
+but could be checked for as noted above for <tt>def()</tt>.  <tt>Z_BUF_ERROR</tt> does not need to be
+checked for here, for the same reasons noted for <tt>def()</tt>.  <tt>Z_STREAM_END</tt> will be
+checked for later.
+<pre><b>
+            ret = inflate(&amp;strm, Z_NO_FLUSH);
+            assert(ret != Z_STREAM_ERROR);  /* state not clobbered */
+            switch (ret) {
+            case Z_NEED_DICT:
+                ret = Z_DATA_ERROR;     /* and fall through */
+            case Z_DATA_ERROR:
+            case Z_MEM_ERROR:
+                (void)inflateEnd(&amp;strm);
+                return ret;
+            }
+</b></pre>
+The output of <tt>inflate()</tt> is handled identically to that of <tt>deflate()</tt>.
+<pre><b>
+            have = CHUNK - strm.avail_out;
+            if (fwrite(out, 1, have, dest) != have || ferror(dest)) {
+                (void)inflateEnd(&amp;strm);
+                return Z_ERRNO;
+            }
+</b></pre>
+The inner <tt>do</tt>-loop ends when <tt>inflate()</tt> has no more output as indicated
+by not filling the output buffer, just as for <tt>deflate()</tt>.  In this case, we cannot
+assert that <tt>strm.avail_in</tt> will be zero, since the deflate stream may end before the file
+does.
+<pre><b>
+        } while (strm.avail_out == 0);
+</b></pre><!-- -->
+The outer <tt>do</tt>-loop ends when <tt>inflate()</tt> reports that it has reached the
+end of the input <em>zlib</em> stream, has completed the decompression and integrity
+check, and has provided all of the output.  This is indicated by the <tt>inflate()</tt>
+return value <tt>Z_STREAM_END</tt>.  The inner loop is guaranteed to leave <tt>ret</tt>
+equal to <tt>Z_STREAM_END</tt> if the last chunk of the input file read contained the end
+of the <em>zlib</em> stream.  So if the return value is not <tt>Z_STREAM_END</tt>, the
+loop continues to read more input.
+<pre><b>
+        /* done when inflate() says it's done */
+    } while (ret != Z_STREAM_END);
+</b></pre><!-- -->
+At this point, decompression successfully completed, or we broke out of the loop due to no
+more data being available from the input file.  If the last <tt>inflate()</tt> return value
+is not <tt>Z_STREAM_END</tt>, then the <em>zlib</em> stream was incomplete and a data error
+is returned.  Otherwise, we return with a happy return value.  Of course, <tt>inflateEnd()</tt>
+is called first to avoid a memory leak.
+<pre><b>
+    /* clean up and return */
+    (void)inflateEnd(&amp;strm);
+    return ret == Z_STREAM_END ? Z_OK : Z_DATA_ERROR;
+}
+</b></pre><!-- -->
+That ends the routines that directly use <em>zlib</em>.  The following routines make this
+a command-line program by running data through the above routines from <tt>stdin</tt> to
+<tt>stdout</tt>, and handling any errors reported by <tt>def()</tt> or <tt>inf()</tt>.
+<p>
+<tt>zerr()</tt> is used to interpret the possible error codes from <tt>def()</tt>
+and <tt>inf()</tt>, as detailed in their comments above, and print out an error message.
+Note that these are only a subset of the possible return values from <tt>deflate()</tt>
+and <tt>inflate()</tt>.
+<pre><b>
+/* report a zlib or i/o error */
+void zerr(int ret)
+{
+    fputs("zpipe: ", stderr);
+    switch (ret) {
+    case Z_ERRNO:
+        if (ferror(stdin))
+            fputs("error reading stdin\n", stderr);
+        if (ferror(stdout))
+            fputs("error writing stdout\n", stderr);
+        break;
+    case Z_STREAM_ERROR:
+        fputs("invalid compression level\n", stderr);
+        break;
+    case Z_DATA_ERROR:
+        fputs("invalid or incomplete deflate data\n", stderr);
+        break;
+    case Z_MEM_ERROR:
+        fputs("out of memory\n", stderr);
+        break;
+    case Z_VERSION_ERROR:
+        fputs("zlib version mismatch!\n", stderr);
+    }
+}
+</b></pre><!-- -->
+Here is the <tt>main()</tt> routine used to test <tt>def()</tt> and <tt>inf()</tt>.  The
+<tt>zpipe</tt> command is simply a compression pipe from <tt>stdin</tt> to <tt>stdout</tt>, if
+no arguments are given, or it is a decompression pipe if <tt>zpipe -d</tt> is used.  If any other
+arguments are provided, no compression or decompression is performed.  Instead a usage
+message is displayed.  Examples are <tt>zpipe < foo.txt > foo.txt.z</tt> to compress, and
+<tt>zpipe -d < foo.txt.z > foo.txt</tt> to decompress.
+<pre><b>
+/* compress or decompress from stdin to stdout */
+int main(int argc, char **argv)
+{
+    int ret;
+
+    /* do compression if no arguments */
+    if (argc == 1) {
+        ret = def(stdin, stdout, Z_DEFAULT_COMPRESSION);
+        if (ret != Z_OK)
+            zerr(ret);
+        return ret;
+    }
+
+    /* do decompression if -d specified */
+    else if (argc == 2 &amp;&amp; strcmp(argv[1], "-d") == 0) {
+        ret = inf(stdin, stdout);
+        if (ret != Z_OK)
+            zerr(ret);
+        return ret;
+    }
+
+    /* otherwise, report usage */
+    else {
+        fputs("zpipe usage: zpipe [-d] &lt; source &gt; dest\n", stderr);
+        return 1;
+    }
+}
+</b></pre>
+<hr>
+<i>Copyright (c) 2004 by Mark Adler<br>Last modified 13 November 2004</i>
+</body>
+</html>
diff --git a/gs/zlib/examples/zpipe.c b/gs/zlib/examples/zpipe.c
new file mode 100644
index 000000000..26abb56a9
--- /dev/null
+++ b/gs/zlib/examples/zpipe.c
@@ -0,0 +1,191 @@
+/* zpipe.c: example of proper use of zlib's inflate() and deflate()
+   Not copyrighted -- provided to the public domain
+   Version 1.2  9 November 2004  Mark Adler */
+
+/* Version history:
+   1.0  30 Oct 2004  First version
+   1.1   8 Nov 2004  Add void casting for unused return values
+                     Use switch statement for inflate() return values
+   1.2   9 Nov 2004  Add assertions to document zlib guarantees
+   1.3   6 Apr 2005  Remove incorrect assertion in inf()
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include "zlib.h"
+
+#define CHUNK 16384
+
+/* Compress from file source to file dest until EOF on source.
+   def() returns Z_OK on success, Z_MEM_ERROR if memory could not be
+   allocated for processing, Z_STREAM_ERROR if an invalid compression
+   level is supplied, Z_VERSION_ERROR if the version of zlib.h and the
+   version of the library linked do not match, or Z_ERRNO if there is
+   an error reading or writing the files. */
+int def(FILE *source, FILE *dest, int level)
+{
+    int ret, flush;
+    unsigned have;
+    z_stream strm;
+    char in[CHUNK];
+    char out[CHUNK];
+
+    /* allocate deflate state */
+    strm.zalloc = Z_NULL;
+    strm.zfree = Z_NULL;
+    strm.opaque = Z_NULL;
+    ret = deflateInit(&strm, level);
+    if (ret != Z_OK)
+        return ret;
+
+    /* compress until end of file */
+    do {
+        strm.avail_in = fread(in, 1, CHUNK, source);
+        if (ferror(source)) {
+            (void)deflateEnd(&strm);
+            return Z_ERRNO;
+        }
+        flush = feof(source) ? Z_FINISH : Z_NO_FLUSH;
+        strm.next_in = in;
+
+        /* run deflate() on input until output buffer not full, finish
+           compression if all of source has been read in */
+        do {
+            strm.avail_out = CHUNK;
+            strm.next_out = out;
+            ret = deflate(&strm, flush);    /* no bad return value */
+            assert(ret != Z_STREAM_ERROR);  /* state not clobbered */
+            have = CHUNK - strm.avail_out;
+            if (fwrite(out, 1, have, dest) != have || ferror(dest)) {
+                (void)deflateEnd(&strm);
+                return Z_ERRNO;
+            }
+        } while (strm.avail_out == 0);
+        assert(strm.avail_in == 0);     /* all input will be used */
+
+        /* done when last data in file processed */
+    } while (flush != Z_FINISH);
+    assert(ret == Z_STREAM_END);        /* stream will be complete */
+
+    /* clean up and return */
+    (void)deflateEnd(&strm);
+    return Z_OK;
+}
+
+/* Decompress from file source to file dest until stream ends or EOF.
+   inf() returns Z_OK on success, Z_MEM_ERROR if memory could not be
+   allocated for processing, Z_DATA_ERROR if the deflate data is
+   invalid or incomplete, Z_VERSION_ERROR if the version of zlib.h and
+   the version of the library linked do not match, or Z_ERRNO if there
+   is an error reading or writing the files. */
+int inf(FILE *source, FILE *dest)
+{
+    int ret;
+    unsigned have;
+    z_stream strm;
+    char in[CHUNK];
+    char out[CHUNK];
+
+    /* allocate inflate state */
+    strm.zalloc = Z_NULL;
+    strm.zfree = Z_NULL;
+    strm.opaque = Z_NULL;
+    strm.avail_in = 0;
+    strm.next_in = Z_NULL;
+    ret = inflateInit(&strm);
+    if (ret != Z_OK)
+        return ret;
+
+    /* decompress until deflate stream ends or end of file */
+    do {
+        strm.avail_in = fread(in, 1, CHUNK, source);
+        if (ferror(source)) {
+            (void)inflateEnd(&strm);
+            return Z_ERRNO;
+        }
+        if (strm.avail_in == 0)
+            break;
+        strm.next_in = in;
+
+        /* run inflate() on input until output buffer not full */
+        do {
+            strm.avail_out = CHUNK;
+            strm.next_out = out;
+            ret = inflate(&strm, Z_NO_FLUSH);
+            assert(ret != Z_STREAM_ERROR);  /* state not clobbered */
+            switch (ret) {
+            case Z_NEED_DICT:
+                ret = Z_DATA_ERROR;     /* and fall through */
+            case Z_DATA_ERROR:
+            case Z_MEM_ERROR:
+                (void)inflateEnd(&strm);
+                return ret;
+            }
+            have = CHUNK - strm.avail_out;
+            if (fwrite(out, 1, have, dest) != have || ferror(dest)) {
+                (void)inflateEnd(&strm);
+                return Z_ERRNO;
+            }
+        } while (strm.avail_out == 0);
+
+        /* done when inflate() says it's done */
+    } while (ret != Z_STREAM_END);
+
+    /* clean up and return */
+    (void)inflateEnd(&strm);
+    return ret == Z_STREAM_END ? Z_OK : Z_DATA_ERROR;
+}
+
+/* report a zlib or i/o error */
+void zerr(int ret)
+{
+    fputs("zpipe: ", stderr);
+    switch (ret) {
+    case Z_ERRNO:
+        if (ferror(stdin))
+            fputs("error reading stdin\n", stderr);
+        if (ferror(stdout))
+            fputs("error writing stdout\n", stderr);
+        break;
+    case Z_STREAM_ERROR:
+        fputs("invalid compression level\n", stderr);
+        break;
+    case Z_DATA_ERROR:
+        fputs("invalid or incomplete deflate data\n", stderr);
+        break;
+    case Z_MEM_ERROR:
+        fputs("out of memory\n", stderr);
+        break;
+    case Z_VERSION_ERROR:
+        fputs("zlib version mismatch!\n", stderr);
+    }
+}
+
+/* compress or decompress from stdin to stdout */
+int main(int argc, char **argv)
+{
+    int ret;
+
+    /* do compression if no arguments */
+    if (argc == 1) {
+        ret = def(stdin, stdout, Z_DEFAULT_COMPRESSION);
+        if (ret != Z_OK)
+            zerr(ret);
+        return ret;
+    }
+
+    /* do decompression if -d specified */
+    else if (argc == 2 && strcmp(argv[1], "-d") == 0) {
+        ret = inf(stdin, stdout);
+        if (ret != Z_OK)
+            zerr(ret);
+        return ret;
+    }
+
+    /* otherwise, report usage */
+    else {
+        fputs("zpipe usage: zpipe [-d] < source > dest\n", stderr);
+        return 1;
+    }
+}
diff --git a/gs/zlib/examples/zran.c b/gs/zlib/examples/zran.c
new file mode 100644
index 000000000..8c7717eb2
--- /dev/null
+++ b/gs/zlib/examples/zran.c
@@ -0,0 +1,404 @@
+/* zran.c -- example of zlib/gzip stream indexing and random access
+ * Copyright (C) 2005 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+   Version 1.0  29 May 2005  Mark Adler */
+
+/* Illustrate the use of Z_BLOCK, inflatePrime(), and inflateSetDictionary()
+   for random access of a compressed file.  A file containing a zlib or gzip
+   stream is provided on the command line.  The compressed stream is decoded in
+   its entirety, and an index built with access points about every SPAN bytes
+   in the uncompressed output.  The compressed file is left open, and can then
+   be read randomly, having to decompress on the average SPAN/2 uncompressed
+   bytes before getting to the desired block of data.
+
+   An access point can be created at the start of any deflate block, by saving
+   the starting file offset and bit of that block, and the 32K bytes of
+   uncompressed data that precede that block.  Also the uncompressed offset of
+   that block is saved to provide a referece for locating a desired starting
+   point in the uncompressed stream.  build_index() works by decompressing the
+   input zlib or gzip stream a block at a time, and at the end of each block
+   deciding if enough uncompressed data has gone by to justify the creation of
+   a new access point.  If so, that point is saved in a data structure that
+   grows as needed to accommodate the points.
+
+   To use the index, an offset in the uncompressed data is provided, for which
+   the latest accees point at or preceding that offset is located in the index.
+   The input file is positioned to the specified location in the index, and if
+   necessary the first few bits of the compressed data is read from the file.
+   inflate is initialized with those bits and the 32K of uncompressed data, and
+   the decompression then proceeds until the desired offset in the file is
+   reached.  Then the decompression continues to read the desired uncompressed
+   data from the file.
+
+   Another approach would be to generate the index on demand.  In that case,
+   requests for random access reads from the compressed data would try to use
+   the index, but if a read far enough past the end of the index is required,
+   then further index entries would be generated and added.
+
+   There is some fair bit of overhead to starting inflation for the random
+   access, mainly copying the 32K byte dictionary.  So if small pieces of the
+   file are being accessed, it would make sense to implement a cache to hold
+   some lookahead and avoid many calls to extract() for small lengths.
+
+   Another way to build an index would be to use inflateCopy().  That would
+   not be constrained to have access points at block boundaries, but requires
+   more memory per access point, and also cannot be saved to file due to the
+   use of pointers in the state.  The approach here allows for storage of the
+   index in a file.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "zlib.h"
+
+#define local static
+
+#define SPAN 1048576L       /* desired distance between access points */
+#define WINSIZE 32768U      /* sliding window size */
+#define CHUNK 16384         /* file input buffer size */
+
+/* access point entry */
+struct point {
+    off_t out;          /* corresponding offset in uncompressed data */
+    off_t in;           /* offset in input file of first full byte */
+    int bits;           /* number of bits (1-7) from byte at in - 1, or 0 */
+    unsigned char window[WINSIZE];  /* preceding 32K of uncompressed data */
+};
+
+/* access point list */
+struct access {
+    int have;           /* number of list entries filled in */
+    int size;           /* number of list entries allocated */
+    struct point *list; /* allocated list */
+};
+
+/* Deallocate an index built by build_index() */
+local void free_index(struct access *index)
+{
+    if (index != NULL) {
+        free(index->list);
+        free(index);
+    }
+}
+
+/* Add an entry to the access point list.  If out of memory, deallocate the
+   existing list and return NULL. */
+local struct access *addpoint(struct access *index, int bits,
+    off_t in, off_t out, unsigned left, unsigned char *window)
+{
+    struct point *next;
+
+    /* if list is empty, create it (start with eight points) */
+    if (index == NULL) {
+        index = malloc(sizeof(struct access));
+        if (index == NULL) return NULL;
+        index->list = malloc(sizeof(struct point) << 3);
+        if (index->list == NULL) {
+            free(index);
+            return NULL;
+        }
+        index->size = 8;
+        index->have = 0;
+    }
+
+    /* if list is full, make it bigger */
+    else if (index->have == index->size) {
+        index->size <<= 1;
+        next = realloc(index->list, sizeof(struct point) * index->size);
+        if (next == NULL) {
+            free_index(index);
+            return NULL;
+        }
+        index->list = next;
+    }
+
+    /* fill in entry and increment how many we have */
+    next = index->list + index->have;
+    next->bits = bits;
+    next->in = in;
+    next->out = out;
+    if (left)
+        memcpy(next->window, window + WINSIZE - left, left);
+    if (left < WINSIZE)
+        memcpy(next->window + left, window, WINSIZE - left);
+    index->have++;
+
+    /* return list, possibly reallocated */
+    return index;
+}
+
+/* Make one entire pass through the compressed stream and build an index, with
+   access points about every span bytes of uncompressed output -- span is
+   chosen to balance the speed of random access against the memory requirements
+   of the list, about 32K bytes per access point.  Note that data after the end
+   of the first zlib or gzip stream in the file is ignored.  build_index()
+   returns the number of access points on success (>= 1), Z_MEM_ERROR for out
+   of memory, Z_DATA_ERROR for an error in the input file, or Z_ERRNO for a
+   file read error.  On success, *built points to the resulting index. */
+local int build_index(FILE *in, off_t span, struct access **built)
+{
+    int ret;
+    off_t totin, totout;        /* our own total counters to avoid 4GB limit */
+    off_t last;                 /* totout value of last access point */
+    struct access *index;       /* access points being generated */
+    z_stream strm;
+    unsigned char input[CHUNK];
+    unsigned char window[WINSIZE];
+
+    /* initialize inflate */
+    strm.zalloc = Z_NULL;
+    strm.zfree = Z_NULL;
+    strm.opaque = Z_NULL;
+    strm.avail_in = 0;
+    strm.next_in = Z_NULL;
+    ret = inflateInit2(&strm, 47);      /* automatic zlib or gzip decoding */
+    if (ret != Z_OK)
+        return ret;
+
+    /* inflate the input, maintain a sliding window, and build an index -- this
+       also validates the integrity of the compressed data using the check
+       information at the end of the gzip or zlib stream */
+    totin = totout = last = 0;
+    index = NULL;               /* will be allocated by first addpoint() */
+    strm.avail_out = 0;
+    do {
+        /* get some compressed data from input file */
+        strm.avail_in = fread(input, 1, CHUNK, in);
+        if (ferror(in)) {
+            ret = Z_ERRNO;
+            goto build_index_error;
+        }
+        if (strm.avail_in == 0) {
+            ret = Z_DATA_ERROR;
+            goto build_index_error;
+        }
+        strm.next_in = input;
+
+        /* process all of that, or until end of stream */
+        do {
+            /* reset sliding window if necessary */
+            if (strm.avail_out == 0) {
+                strm.avail_out = WINSIZE;
+                strm.next_out = window;
+            }
+
+            /* inflate until out of input, output, or at end of block --
+               update the total input and output counters */
+            totin += strm.avail_in;
+            totout += strm.avail_out;
+            ret = inflate(&strm, Z_BLOCK);      /* return at end of block */
+            totin -= strm.avail_in;
+            totout -= strm.avail_out;
+            if (ret == Z_NEED_DICT)
+                ret = Z_DATA_ERROR;
+            if (ret == Z_MEM_ERROR || ret == Z_DATA_ERROR)
+                goto build_index_error;
+            if (ret == Z_STREAM_END)
+                break;
+
+            /* if at end of block, consider adding an index entry (note that if
+               data_type indicates an end-of-block, then all of the
+               uncompressed data from that block has been delivered, and none
+               of the compressed data after that block has been consumed,
+               except for up to seven bits) -- the totout == 0 provides an
+               entry point after the zlib or gzip header, and assures that the
+               index always has at least one access point; we avoid creating an
+               access point after the last block by checking bit 6 of data_type
+             */
+            if ((strm.data_type & 128) && !(strm.data_type & 64) &&
+                (totout == 0 || totout - last > span)) {
+                index = addpoint(index, strm.data_type & 7, totin,
+                                 totout, strm.avail_out, window);
+                if (index == NULL) {
+                    ret = Z_MEM_ERROR;
+                    goto build_index_error;
+                }
+                last = totout;
+            }
+        } while (strm.avail_in != 0);
+    } while (ret != Z_STREAM_END);
+
+    /* clean up and return index (release unused entries in list) */
+    (void)inflateEnd(&strm);
+    index = realloc(index, sizeof(struct point) * index->have);
+    index->size = index->have;
+    *built = index;
+    return index->size;
+
+    /* return error */
+  build_index_error:
+    (void)inflateEnd(&strm);
+    if (index != NULL)
+        free_index(index);
+    return ret;
+}
+
+/* Use the index to read len bytes from offset into buf, return bytes read or
+   negative for error (Z_DATA_ERROR or Z_MEM_ERROR).  If data is requested past
+   the end of the uncompressed data, then extract() will return a value less
+   than len, indicating how much as actually read into buf.  This function
+   should not return a data error unless the file was modified since the index
+   was generated.  extract() may also return Z_ERRNO if there is an error on
+   reading or seeking the input file. */
+local int extract(FILE *in, struct access *index, off_t offset,
+                  unsigned char *buf, int len)
+{
+    int ret, skip;
+    z_stream strm;
+    struct point *here;
+    unsigned char input[CHUNK];
+    unsigned char discard[WINSIZE];
+
+    /* proceed only if something reasonable to do */
+    if (len < 0)
+        return 0;
+
+    /* find where in stream to start */
+    here = index->list;
+    ret = index->have;
+    while (--ret && here[1].out <= offset)
+        here++;
+
+    /* initialize file and inflate state to start there */
+    strm.zalloc = Z_NULL;
+    strm.zfree = Z_NULL;
+    strm.opaque = Z_NULL;
+    strm.avail_in = 0;
+    strm.next_in = Z_NULL;
+    ret = inflateInit2(&strm, -15);         /* raw inflate */
+    if (ret != Z_OK)
+        return ret;
+    ret = fseeko(in, here->in - (here->bits ? 1 : 0), SEEK_SET);
+    if (ret == -1)
+        goto extract_ret;
+    if (here->bits) {
+        ret = getc(in);
+        if (ret == -1) {
+            ret = ferror(in) ? Z_ERRNO : Z_DATA_ERROR;
+            goto extract_ret;
+        }
+        (void)inflatePrime(&strm, here->bits, ret >> (8 - here->bits));
+    }
+    (void)inflateSetDictionary(&strm, here->window, WINSIZE);
+
+    /* skip uncompressed bytes until offset reached, then satisfy request */
+    offset -= here->out;
+    strm.avail_in = 0;
+    skip = 1;                               /* while skipping to offset */
+    do {
+        /* define where to put uncompressed data, and how much */
+        if (offset == 0 && skip) {          /* at offset now */
+            strm.avail_out = len;
+            strm.next_out = buf;
+            skip = 0;                       /* only do this once */
+        }
+        if (offset > WINSIZE) {             /* skip WINSIZE bytes */
+            strm.avail_out = WINSIZE;
+            strm.next_out = discard;
+            offset -= WINSIZE;
+        }
+        else if (offset != 0) {             /* last skip */
+            strm.avail_out = (unsigned)offset;
+            strm.next_out = discard;
+            offset = 0;
+        }
+
+        /* uncompress until avail_out filled, or end of stream */
+        do {
+            if (strm.avail_in == 0) {
+                strm.avail_in = fread(input, 1, CHUNK, in);
+                if (ferror(in)) {
+                    ret = Z_ERRNO;
+                    goto extract_ret;
+                }
+                if (strm.avail_in == 0) {
+                    ret = Z_DATA_ERROR;
+                    goto extract_ret;
+                }
+                strm.next_in = input;
+            }
+            ret = inflate(&strm, Z_NO_FLUSH);       /* normal inflate */
+            if (ret == Z_NEED_DICT)
+                ret = Z_DATA_ERROR;
+            if (ret == Z_MEM_ERROR || ret == Z_DATA_ERROR)
+                goto extract_ret;
+            if (ret == Z_STREAM_END)
+                break;
+        } while (strm.avail_out != 0);
+
+        /* if reach end of stream, then don't keep trying to get more */
+        if (ret == Z_STREAM_END)
+            break;
+
+        /* do until offset reached and requested data read, or stream ends */
+    } while (skip);
+
+    /* compute number of uncompressed bytes read after offset */
+    ret = skip ? 0 : len - strm.avail_out;
+
+    /* clean up and return bytes read or error */
+  extract_ret:
+    (void)inflateEnd(&strm);
+    return ret;
+}
+
+/* Demonstrate the use of build_index() and extract() by processing the file
+   provided on the command line, and the extracting 16K from about 2/3rds of
+   the way through the uncompressed output, and writing that to stdout. */
+int main(int argc, char **argv)
+{
+    int len;
+    off_t offset;
+    FILE *in;
+    struct access *index;
+    unsigned char buf[CHUNK];
+
+    /* open input file */
+    if (argc != 2) {
+        fprintf(stderr, "usage: zran file.gz\n");
+        return 1;
+    }
+    in = fopen(argv[1], "rb");
+    if (in == NULL) {
+        fprintf(stderr, "zran: could not open %s for reading\n", argv[1]);
+        return 1;
+    }
+
+    /* build index */
+    len = build_index(in, SPAN, &index);
+    if (len < 0) {
+        fclose(in);
+        switch (len) {
+        case Z_MEM_ERROR:
+            fprintf(stderr, "zran: out of memory\n");
+            break;
+        case Z_DATA_ERROR:
+            fprintf(stderr, "zran: compressed data error in %s\n", argv[1]);
+            break;
+        case Z_ERRNO:
+            fprintf(stderr, "zran: read error on %s\n", argv[1]);
+            break;
+        default:
+            fprintf(stderr, "zran: error %d while building index\n", len);
+        }
+        return 1;
+    }
+    fprintf(stderr, "zran: built index with %d access points\n", len);
+
+    /* use index by reading some bytes from an arbitrary offset */
+    offset = (index->list[index->have - 1].out << 1) / 3;
+    len = extract(in, index, offset, buf, CHUNK);
+    if (len < 0)
+        fprintf(stderr, "zran: extraction failed: %s error\n",
+                len == Z_MEM_ERROR ? "out of memory" : "input corrupted");
+    else {
+        fwrite(buf, 1, len, stdout);
+        fprintf(stderr, "zran: extracted %d bytes at %llu\n", len, offset);
+    }
+
+    /* clean up and exit */
+    free_index(index);
+    fclose(in);
+    return 0;
+}
diff --git a/gs/zlib/gzio.c b/gs/zlib/gzio.c
new file mode 100644
index 000000000..7e90f4928
--- /dev/null
+++ b/gs/zlib/gzio.c
@@ -0,0 +1,1026 @@
+/* gzio.c -- IO on .gz files
+ * Copyright (C) 1995-2005 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ *
+ * Compile this file with -DNO_GZCOMPRESS to avoid the compression code.
+ */
+
+/* @(#) $Id$ */
+
+#include <stdio.h>
+
+#include "zutil.h"
+
+#ifdef NO_DEFLATE       /* for compatibility with old definition */
+#  define NO_GZCOMPRESS
+#endif
+
+#ifndef NO_DUMMY_DECL
+struct internal_state {int dummy;}; /* for buggy compilers */
+#endif
+
+#ifndef Z_BUFSIZE
+#  ifdef MAXSEG_64K
+#    define Z_BUFSIZE 4096 /* minimize memory usage for 16-bit DOS */
+#  else
+#    define Z_BUFSIZE 16384
+#  endif
+#endif
+#ifndef Z_PRINTF_BUFSIZE
+#  define Z_PRINTF_BUFSIZE 4096
+#endif
+
+#ifdef __MVS__
+#  pragma map (fdopen , "\174\174FDOPEN")
+   FILE *fdopen(int, const char *);
+#endif
+
+#ifndef STDC
+extern voidp  malloc OF((uInt size));
+extern void   free   OF((voidpf ptr));
+#endif
+
+#define ALLOC(size) malloc(size)
+#define TRYFREE(p) {if (p) free(p);}
+
+static int const gz_magic[2] = {0x1f, 0x8b}; /* gzip magic header */
+
+/* gzip flag byte */
+#define ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
+#define HEAD_CRC     0x02 /* bit 1 set: header CRC present */
+#define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
+#define ORIG_NAME    0x08 /* bit 3 set: original file name present */
+#define COMMENT      0x10 /* bit 4 set: file comment present */
+#define RESERVED     0xE0 /* bits 5..7: reserved */
+
+typedef struct gz_stream {
+    z_stream stream;
+    int      z_err;   /* error code for last stream operation */
+    int      z_eof;   /* set if end of input file */
+    FILE     *file;   /* .gz file */
+    Byte     *inbuf;  /* input buffer */
+    Byte     *outbuf; /* output buffer */
+    uLong    crc;     /* crc32 of uncompressed data */
+    char     *msg;    /* error message */
+    char     *path;   /* path name for debugging only */
+    int      transparent; /* 1 if input file is not a .gz file */
+    char     mode;    /* 'w' or 'r' */
+    z_off_t  start;   /* start of compressed data in file (header skipped) */
+    z_off_t  in;      /* bytes into deflate or inflate */
+    z_off_t  out;     /* bytes out of deflate or inflate */
+    int      back;    /* one character push-back */
+    int      last;    /* true if push-back is last character */
+} gz_stream;
+
+
+local gzFile gz_open      OF((const char *path, const char *mode, int  fd));
+local int do_flush        OF((gzFile file, int flush));
+local int    get_byte     OF((gz_stream *s));
+local void   check_header OF((gz_stream *s));
+local int    destroy      OF((gz_stream *s));
+local void   putLong      OF((FILE *file, uLong x));
+local uLong  getLong      OF((gz_stream *s));
+
+/* ===========================================================================
+     Opens a gzip (.gz) file for reading or writing. The mode parameter
+   is as in fopen ("rb" or "wb"). The file is given either by file descriptor
+   or path name (if fd == -1).
+     gz_open returns NULL if the file could not be opened or if there was
+   insufficient memory to allocate the (de)compression state; errno
+   can be checked to distinguish the two cases (if errno is zero, the
+   zlib error is Z_MEM_ERROR).
+*/
+local gzFile gz_open (path, mode, fd)
+    const char *path;
+    const char *mode;
+    int  fd;
+{
+    int err;
+    int level = Z_DEFAULT_COMPRESSION; /* compression level */
+    int strategy = Z_DEFAULT_STRATEGY; /* compression strategy */
+    char *p = (char*)mode;
+    gz_stream *s;
+    char fmode[80]; /* copy of mode, without the compression level */
+    char *m = fmode;
+
+    if (!path || !mode) return Z_NULL;
+
+    s = (gz_stream *)ALLOC(sizeof(gz_stream));
+    if (!s) return Z_NULL;
+
+    s->stream.zalloc = (alloc_func)0;
+    s->stream.zfree = (free_func)0;
+    s->stream.opaque = (voidpf)0;
+    s->stream.next_in = s->inbuf = Z_NULL;
+    s->stream.next_out = s->outbuf = Z_NULL;
+    s->stream.avail_in = s->stream.avail_out = 0;
+    s->file = NULL;
+    s->z_err = Z_OK;
+    s->z_eof = 0;
+    s->in = 0;
+    s->out = 0;
+    s->back = EOF;
+    s->crc = crc32(0L, Z_NULL, 0);
+    s->msg = NULL;
+    s->transparent = 0;
+
+    s->path = (char*)ALLOC(strlen(path)+1);
+    if (s->path == NULL) {
+        return destroy(s), (gzFile)Z_NULL;
+    }
+    strcpy(s->path, path); /* do this early for debugging */
+
+    s->mode = '\0';
+    do {
+        if (*p == 'r') s->mode = 'r';
+        if (*p == 'w' || *p == 'a') s->mode = 'w';
+        if (*p >= '0' && *p <= '9') {
+            level = *p - '0';
+        } else if (*p == 'f') {
+          strategy = Z_FILTERED;
+        } else if (*p == 'h') {
+          strategy = Z_HUFFMAN_ONLY;
+        } else if (*p == 'R') {
+          strategy = Z_RLE;
+        } else {
+            *m++ = *p; /* copy the mode */
+        }
+    } while (*p++ && m != fmode + sizeof(fmode));
+    if (s->mode == '\0') return destroy(s), (gzFile)Z_NULL;
+
+    if (s->mode == 'w') {
+#ifdef NO_GZCOMPRESS
+        err = Z_STREAM_ERROR;
+#else
+        err = deflateInit2(&(s->stream), level,
+                           Z_DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL, strategy);
+        /* windowBits is passed < 0 to suppress zlib header */
+
+        s->stream.next_out = s->outbuf = (Byte*)ALLOC(Z_BUFSIZE);
+#endif
+        if (err != Z_OK || s->outbuf == Z_NULL) {
+            return destroy(s), (gzFile)Z_NULL;
+        }
+    } else {
+        s->stream.next_in  = s->inbuf = (Byte*)ALLOC(Z_BUFSIZE);
+
+        err = inflateInit2(&(s->stream), -MAX_WBITS);
+        /* windowBits is passed < 0 to tell that there is no zlib header.
+         * Note that in this case inflate *requires* an extra "dummy" byte
+         * after the compressed stream in order to complete decompression and
+         * return Z_STREAM_END. Here the gzip CRC32 ensures that 4 bytes are
+         * present after the compressed stream.
+         */
+        if (err != Z_OK || s->inbuf == Z_NULL) {
+            return destroy(s), (gzFile)Z_NULL;
+        }
+    }
+    s->stream.avail_out = Z_BUFSIZE;
+
+    errno = 0;
+    s->file = fd < 0 ? F_OPEN(path, fmode) : (FILE*)fdopen(fd, fmode);
+
+    if (s->file == NULL) {
+        return destroy(s), (gzFile)Z_NULL;
+    }
+    if (s->mode == 'w') {
+        /* Write a very simple .gz header:
+         */
+        fprintf(s->file, "%c%c%c%c%c%c%c%c%c%c", gz_magic[0], gz_magic[1],
+             Z_DEFLATED, 0 /*flags*/, 0,0,0,0 /*time*/, 0 /*xflags*/, OS_CODE);
+        s->start = 10L;
+        /* We use 10L instead of ftell(s->file) to because ftell causes an
+         * fflush on some systems. This version of the library doesn't use
+         * start anyway in write mode, so this initialization is not
+         * necessary.
+         */
+    } else {
+        check_header(s); /* skip the .gz header */
+        s->start = ftell(s->file) - s->stream.avail_in;
+    }
+
+    return (gzFile)s;
+}
+
+/* ===========================================================================
+     Opens a gzip (.gz) file for reading or writing.
+*/
+gzFile ZEXPORT gzopen (path, mode)
+    const char *path;
+    const char *mode;
+{
+    return gz_open (path, mode, -1);
+}
+
+/* ===========================================================================
+     Associate a gzFile with the file descriptor fd. fd is not dup'ed here
+   to mimic the behavio(u)r of fdopen.
+*/
+gzFile ZEXPORT gzdopen (fd, mode)
+    int fd;
+    const char *mode;
+{
+    char name[46];      /* allow for up to 128-bit integers */
+
+    if (fd < 0) return (gzFile)Z_NULL;
+    sprintf(name, "<fd:%d>", fd); /* for debugging */
+
+    return gz_open (name, mode, fd);
+}
+
+/* ===========================================================================
+ * Update the compression level and strategy
+ */
+int ZEXPORT gzsetparams (file, level, strategy)
+    gzFile file;
+    int level;
+    int strategy;
+{
+    gz_stream *s = (gz_stream*)file;
+
+    if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR;
+
+    /* Make room to allow flushing */
+    if (s->stream.avail_out == 0) {
+
+        s->stream.next_out = s->outbuf;
+        if (fwrite(s->outbuf, 1, Z_BUFSIZE, s->file) != Z_BUFSIZE) {
+            s->z_err = Z_ERRNO;
+        }
+        s->stream.avail_out = Z_BUFSIZE;
+    }
+
+    return deflateParams (&(s->stream), level, strategy);
+}
+
+/* ===========================================================================
+     Read a byte from a gz_stream; update next_in and avail_in. Return EOF
+   for end of file.
+   IN assertion: the stream s has been sucessfully opened for reading.
+*/
+local int get_byte(s)
+    gz_stream *s;
+{
+    if (s->z_eof) return EOF;
+    if (s->stream.avail_in == 0) {
+        errno = 0;
+        s->stream.avail_in = (uInt)fread(s->inbuf, 1, Z_BUFSIZE, s->file);
+        if (s->stream.avail_in == 0) {
+            s->z_eof = 1;
+            if (ferror(s->file)) s->z_err = Z_ERRNO;
+            return EOF;
+        }
+        s->stream.next_in = s->inbuf;
+    }
+    s->stream.avail_in--;
+    return *(s->stream.next_in)++;
+}
+
+/* ===========================================================================
+      Check the gzip header of a gz_stream opened for reading. Set the stream
+    mode to transparent if the gzip magic header is not present; set s->err
+    to Z_DATA_ERROR if the magic header is present but the rest of the header
+    is incorrect.
+    IN assertion: the stream s has already been created sucessfully;
+       s->stream.avail_in is zero for the first time, but may be non-zero
+       for concatenated .gz files.
+*/
+local void check_header(s)
+    gz_stream *s;
+{
+    int method; /* method byte */
+    int flags;  /* flags byte */
+    uInt len;
+    int c;
+
+    /* Assure two bytes in the buffer so we can peek ahead -- handle case
+       where first byte of header is at the end of the buffer after the last
+       gzip segment */
+    len = s->stream.avail_in;
+    if (len < 2) {
+        if (len) s->inbuf[0] = s->stream.next_in[0];
+        errno = 0;
+        len = (uInt)fread(s->inbuf + len, 1, Z_BUFSIZE >> len, s->file);
+        if (len == 0 && ferror(s->file)) s->z_err = Z_ERRNO;
+        s->stream.avail_in += len;
+        s->stream.next_in = s->inbuf;
+        if (s->stream.avail_in < 2) {
+            s->transparent = s->stream.avail_in;
+            return;
+        }
+    }
+
+    /* Peek ahead to check the gzip magic header */
+    if (s->stream.next_in[0] != gz_magic[0] ||
+        s->stream.next_in[1] != gz_magic[1]) {
+        s->transparent = 1;
+        return;
+    }
+    s->stream.avail_in -= 2;
+    s->stream.next_in += 2;
+
+    /* Check the rest of the gzip header */
+    method = get_byte(s);
+    flags = get_byte(s);
+    if (method != Z_DEFLATED || (flags & RESERVED) != 0) {
+        s->z_err = Z_DATA_ERROR;
+        return;
+    }
+
+    /* Discard time, xflags and OS code: */
+    for (len = 0; len < 6; len++) (void)get_byte(s);
+
+    if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */
+        len  =  (uInt)get_byte(s);
+        len += ((uInt)get_byte(s))<<8;
+        /* len is garbage if EOF but the loop below will quit anyway */
+        while (len-- != 0 && get_byte(s) != EOF) ;
+    }
+    if ((flags & ORIG_NAME) != 0) { /* skip the original file name */
+        while ((c = get_byte(s)) != 0 && c != EOF) ;
+    }
+    if ((flags & COMMENT) != 0) {   /* skip the .gz file comment */
+        while ((c = get_byte(s)) != 0 && c != EOF) ;
+    }
+    if ((flags & HEAD_CRC) != 0) {  /* skip the header crc */
+        for (len = 0; len < 2; len++) (void)get_byte(s);
+    }
+    s->z_err = s->z_eof ? Z_DATA_ERROR : Z_OK;
+}
+
+ /* ===========================================================================
+ * Cleanup then free the given gz_stream. Return a zlib error code.
+   Try freeing in the reverse order of allocations.
+ */
+local int destroy (s)
+    gz_stream *s;
+{
+    int err = Z_OK;
+
+    if (!s) return Z_STREAM_ERROR;
+
+    TRYFREE(s->msg);
+
+    if (s->stream.state != NULL) {
+        if (s->mode == 'w') {
+#ifdef NO_GZCOMPRESS
+            err = Z_STREAM_ERROR;
+#else
+            err = deflateEnd(&(s->stream));
+#endif
+        } else if (s->mode == 'r') {
+            err = inflateEnd(&(s->stream));
+        }
+    }
+    if (s->file != NULL && fclose(s->file)) {
+#ifdef ESPIPE
+        if (errno != ESPIPE) /* fclose is broken for pipes in HP/UX */
+#endif
+            err = Z_ERRNO;
+    }
+    if (s->z_err < 0) err = s->z_err;
+
+    TRYFREE(s->inbuf);
+    TRYFREE(s->outbuf);
+    TRYFREE(s->path);
+    TRYFREE(s);
+    return err;
+}
+
+/* ===========================================================================
+     Reads the given number of uncompressed bytes from the compressed file.
+   gzread returns the number of bytes actually read (0 for end of file).
+*/
+int ZEXPORT gzread (file, buf, len)
+    gzFile file;
+    voidp buf;
+    unsigned len;
+{
+    gz_stream *s = (gz_stream*)file;
+    Bytef *start = (Bytef*)buf; /* starting point for crc computation */
+    Byte  *next_out; /* == stream.next_out but not forced far (for MSDOS) */
+
+    if (s == NULL || s->mode != 'r') return Z_STREAM_ERROR;
+
+    if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO) return -1;
+    if (s->z_err == Z_STREAM_END) return 0;  /* EOF */
+
+    next_out = (Byte*)buf;
+    s->stream.next_out = (Bytef*)buf;
+    s->stream.avail_out = len;
+
+    if (s->stream.avail_out && s->back != EOF) {
+        *next_out++ = s->back;
+        s->stream.next_out++;
+        s->stream.avail_out--;
+        s->back = EOF;
+        s->out++;
+        start++;
+        if (s->last) {
+            s->z_err = Z_STREAM_END;
+            return 1;
+        }
+    }
+
+    while (s->stream.avail_out != 0) {
+
+        if (s->transparent) {
+            /* Copy first the lookahead bytes: */
+            uInt n = s->stream.avail_in;
+            if (n > s->stream.avail_out) n = s->stream.avail_out;
+            if (n > 0) {
+                zmemcpy(s->stream.next_out, s->stream.next_in, n);
+                next_out += n;
+                s->stream.next_out = next_out;
+                s->stream.next_in   += n;
+                s->stream.avail_out -= n;
+                s->stream.avail_in  -= n;
+            }
+            if (s->stream.avail_out > 0) {
+                s->stream.avail_out -=
+                    (uInt)fread(next_out, 1, s->stream.avail_out, s->file);
+            }
+            len -= s->stream.avail_out;
+            s->in  += len;
+            s->out += len;
+            if (len == 0) s->z_eof = 1;
+            return (int)len;
+        }
+        if (s->stream.avail_in == 0 && !s->z_eof) {
+
+            errno = 0;
+            s->stream.avail_in = (uInt)fread(s->inbuf, 1, Z_BUFSIZE, s->file);
+            if (s->stream.avail_in == 0) {
+                s->z_eof = 1;
+                if (ferror(s->file)) {
+                    s->z_err = Z_ERRNO;
+                    break;
+                }
+            }
+            s->stream.next_in = s->inbuf;
+        }
+        s->in += s->stream.avail_in;
+        s->out += s->stream.avail_out;
+        s->z_err = inflate(&(s->stream), Z_NO_FLUSH);
+        s->in -= s->stream.avail_in;
+        s->out -= s->stream.avail_out;
+
+        if (s->z_err == Z_STREAM_END) {
+            /* Check CRC and original size */
+            s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start));
+            start = s->stream.next_out;
+
+            if (getLong(s) != s->crc) {
+                s->z_err = Z_DATA_ERROR;
+            } else {
+                (void)getLong(s);
+                /* The uncompressed length returned by above getlong() may be
+                 * different from s->out in case of concatenated .gz files.
+                 * Check for such files:
+                 */
+                check_header(s);
+                if (s->z_err == Z_OK) {
+                    inflateReset(&(s->stream));
+                    s->crc = crc32(0L, Z_NULL, 0);
+                }
+            }
+        }
+        if (s->z_err != Z_OK || s->z_eof) break;
+    }
+    s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start));
+
+    if (len == s->stream.avail_out &&
+        (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO))
+        return -1;
+    return (int)(len - s->stream.avail_out);
+}
+
+
+/* ===========================================================================
+      Reads one byte from the compressed file. gzgetc returns this byte
+   or -1 in case of end of file or error.
+*/
+int ZEXPORT gzgetc(file)
+    gzFile file;
+{
+    unsigned char c;
+
+    return gzread(file, &c, 1) == 1 ? c : -1;
+}
+
+
+/* ===========================================================================
+      Push one byte back onto the stream.
+*/
+int ZEXPORT gzungetc(c, file)
+    int c;
+    gzFile file;
+{
+    gz_stream *s = (gz_stream*)file;
+
+    if (s == NULL || s->mode != 'r' || c == EOF || s->back != EOF) return EOF;
+    s->back = c;
+    s->out--;
+    s->last = (s->z_err == Z_STREAM_END);
+    if (s->last) s->z_err = Z_OK;
+    s->z_eof = 0;
+    return c;
+}
+
+
+/* ===========================================================================
+      Reads bytes from the compressed file until len-1 characters are
+   read, or a newline character is read and transferred to buf, or an
+   end-of-file condition is encountered.  The string is then terminated
+   with a null character.
+      gzgets returns buf, or Z_NULL in case of error.
+
+      The current implementation is not optimized at all.
+*/
+char * ZEXPORT gzgets(file, buf, len)
+    gzFile file;
+    char *buf;
+    int len;
+{
+    char *b = buf;
+    if (buf == Z_NULL || len <= 0) return Z_NULL;
+
+    while (--len > 0 && gzread(file, buf, 1) == 1 && *buf++ != '\n') ;
+    *buf = '\0';
+    return b == buf && len > 0 ? Z_NULL : b;
+}
+
+
+#ifndef NO_GZCOMPRESS
+/* ===========================================================================
+     Writes the given number of uncompressed bytes into the compressed file.
+   gzwrite returns the number of bytes actually written (0 in case of error).
+*/
+int ZEXPORT gzwrite (file, buf, len)
+    gzFile file;
+    voidpc buf;
+    unsigned len;
+{
+    gz_stream *s = (gz_stream*)file;
+
+    if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR;
+
+    s->stream.next_in = (Bytef*)buf;
+    s->stream.avail_in = len;
+
+    while (s->stream.avail_in != 0) {
+
+        if (s->stream.avail_out == 0) {
+
+            s->stream.next_out = s->outbuf;
+            if (fwrite(s->outbuf, 1, Z_BUFSIZE, s->file) != Z_BUFSIZE) {
+                s->z_err = Z_ERRNO;
+                break;
+            }
+            s->stream.avail_out = Z_BUFSIZE;
+        }
+        s->in += s->stream.avail_in;
+        s->out += s->stream.avail_out;
+        s->z_err = deflate(&(s->stream), Z_NO_FLUSH);
+        s->in -= s->stream.avail_in;
+        s->out -= s->stream.avail_out;
+        if (s->z_err != Z_OK) break;
+    }
+    s->crc = crc32(s->crc, (const Bytef *)buf, len);
+
+    return (int)(len - s->stream.avail_in);
+}
+
+
+/* ===========================================================================
+     Converts, formats, and writes the args to the compressed file under
+   control of the format string, as in fprintf. gzprintf returns the number of
+   uncompressed bytes actually written (0 in case of error).
+*/
+#ifdef STDC
+#include <stdarg.h>
+
+int ZEXPORTVA gzprintf (gzFile file, const char *format, /* args */ ...)
+{
+    char buf[Z_PRINTF_BUFSIZE];
+    va_list va;
+    int len;
+
+    buf[sizeof(buf) - 1] = 0;
+    va_start(va, format);
+#ifdef NO_vsnprintf
+#  ifdef HAS_vsprintf_void
+    (void)vsprintf(buf, format, va);
+    va_end(va);
+    for (len = 0; len < sizeof(buf); len++)
+        if (buf[len] == 0) break;
+#  else
+    len = vsprintf(buf, format, va);
+    va_end(va);
+#  endif
+#else
+#  ifdef HAS_vsnprintf_void
+    (void)vsnprintf(buf, sizeof(buf), format, va);
+    va_end(va);
+    len = strlen(buf);
+#  else
+    len = vsnprintf(buf, sizeof(buf), format, va);
+    va_end(va);
+#  endif
+#endif
+    if (len <= 0 || len >= (int)sizeof(buf) || buf[sizeof(buf) - 1] != 0)
+        return 0;
+    return gzwrite(file, buf, (unsigned)len);
+}
+#else /* not ANSI C */
+
+int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
+                       a11, a12, a13, a14, a15, a16, a17, a18, a19, a20)
+    gzFile file;
+    const char *format;
+    int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
+        a11, a12, a13, a14, a15, a16, a17, a18, a19, a20;
+{
+    char buf[Z_PRINTF_BUFSIZE];
+    int len;
+
+    buf[sizeof(buf) - 1] = 0;
+#ifdef NO_snprintf
+#  ifdef HAS_sprintf_void
+    sprintf(buf, format, a1, a2, a3, a4, a5, a6, a7, a8,
+            a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
+    for (len = 0; len < sizeof(buf); len++)
+        if (buf[len] == 0) break;
+#  else
+    len = sprintf(buf, format, a1, a2, a3, a4, a5, a6, a7, a8,
+                a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
+#  endif
+#else
+#  ifdef HAS_snprintf_void
+    snprintf(buf, sizeof(buf), format, a1, a2, a3, a4, a5, a6, a7, a8,
+             a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
+    len = strlen(buf);
+#  else
+    len = snprintf(buf, sizeof(buf), format, a1, a2, a3, a4, a5, a6, a7, a8,
+                 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
+#  endif
+#endif
+    if (len <= 0 || len >= sizeof(buf) || buf[sizeof(buf) - 1] != 0)
+        return 0;
+    return gzwrite(file, buf, len);
+}
+#endif
+
+/* ===========================================================================
+      Writes c, converted to an unsigned char, into the compressed file.
+   gzputc returns the value that was written, or -1 in case of error.
+*/
+int ZEXPORT gzputc(file, c)
+    gzFile file;
+    int c;
+{
+    unsigned char cc = (unsigned char) c; /* required for big endian systems */
+
+    return gzwrite(file, &cc, 1) == 1 ? (int)cc : -1;
+}
+
+
+/* ===========================================================================
+      Writes the given null-terminated string to the compressed file, excluding
+   the terminating null character.
+      gzputs returns the number of characters written, or -1 in case of error.
+*/
+int ZEXPORT gzputs(file, s)
+    gzFile file;
+    const char *s;
+{
+    return gzwrite(file, (char*)s, (unsigned)strlen(s));
+}
+
+
+/* ===========================================================================
+     Flushes all pending output into the compressed file. The parameter
+   flush is as in the deflate() function.
+*/
+local int do_flush (file, flush)
+    gzFile file;
+    int flush;
+{
+    uInt len;
+    int done = 0;
+    gz_stream *s = (gz_stream*)file;
+
+    if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR;
+
+    s->stream.avail_in = 0; /* should be zero already anyway */
+
+    for (;;) {
+        len = Z_BUFSIZE - s->stream.avail_out;
+
+        if (len != 0) {
+            if ((uInt)fwrite(s->outbuf, 1, len, s->file) != len) {
+                s->z_err = Z_ERRNO;
+                return Z_ERRNO;
+            }
+            s->stream.next_out = s->outbuf;
+            s->stream.avail_out = Z_BUFSIZE;
+        }
+        if (done) break;
+        s->out += s->stream.avail_out;
+        s->z_err = deflate(&(s->stream), flush);
+        s->out -= s->stream.avail_out;
+
+        /* Ignore the second of two consecutive flushes: */
+        if (len == 0 && s->z_err == Z_BUF_ERROR) s->z_err = Z_OK;
+
+        /* deflate has finished flushing only when it hasn't used up
+         * all the available space in the output buffer:
+         */
+        done = (s->stream.avail_out != 0 || s->z_err == Z_STREAM_END);
+
+        if (s->z_err != Z_OK && s->z_err != Z_STREAM_END) break;
+    }
+    return  s->z_err == Z_STREAM_END ? Z_OK : s->z_err;
+}
+
+int ZEXPORT gzflush (file, flush)
+     gzFile file;
+     int flush;
+{
+    gz_stream *s = (gz_stream*)file;
+    int err = do_flush (file, flush);
+
+    if (err) return err;
+    fflush(s->file);
+    return  s->z_err == Z_STREAM_END ? Z_OK : s->z_err;
+}
+#endif /* NO_GZCOMPRESS */
+
+/* ===========================================================================
+      Sets the starting position for the next gzread or gzwrite on the given
+   compressed file. The offset represents a number of bytes in the
+      gzseek returns the resulting offset location as measured in bytes from
+   the beginning of the uncompressed stream, or -1 in case of error.
+      SEEK_END is not implemented, returns error.
+      In this version of the library, gzseek can be extremely slow.
+*/
+z_off_t ZEXPORT gzseek (file, offset, whence)
+    gzFile file;
+    z_off_t offset;
+    int whence;
+{
+    gz_stream *s = (gz_stream*)file;
+
+    if (s == NULL || whence == SEEK_END ||
+        s->z_err == Z_ERRNO || s->z_err == Z_DATA_ERROR) {
+        return -1L;
+    }
+
+    if (s->mode == 'w') {
+#ifdef NO_GZCOMPRESS
+        return -1L;
+#else
+        if (whence == SEEK_SET) {
+            offset -= s->in;
+        }
+        if (offset < 0) return -1L;
+
+        /* At this point, offset is the number of zero bytes to write. */
+        if (s->inbuf == Z_NULL) {
+            s->inbuf = (Byte*)ALLOC(Z_BUFSIZE); /* for seeking */
+            if (s->inbuf == Z_NULL) return -1L;
+            zmemzero(s->inbuf, Z_BUFSIZE);
+        }
+        while (offset > 0)  {
+            uInt size = Z_BUFSIZE;
+            if (offset < Z_BUFSIZE) size = (uInt)offset;
+
+            size = gzwrite(file, s->inbuf, size);
+            if (size == 0) return -1L;
+
+            offset -= size;
+        }
+        return s->in;
+#endif
+    }
+    /* Rest of function is for reading only */
+
+    /* compute absolute position */
+    if (whence == SEEK_CUR) {
+        offset += s->out;
+    }
+    if (offset < 0) return -1L;
+
+    if (s->transparent) {
+        /* map to fseek */
+        s->back = EOF;
+        s->stream.avail_in = 0;
+        s->stream.next_in = s->inbuf;
+        if (fseek(s->file, offset, SEEK_SET) < 0) return -1L;
+
+        s->in = s->out = offset;
+        return offset;
+    }
+
+    /* For a negative seek, rewind and use positive seek */
+    if (offset >= s->out) {
+        offset -= s->out;
+    } else if (gzrewind(file) < 0) {
+        return -1L;
+    }
+    /* offset is now the number of bytes to skip. */
+
+    if (offset != 0 && s->outbuf == Z_NULL) {
+        s->outbuf = (Byte*)ALLOC(Z_BUFSIZE);
+        if (s->outbuf == Z_NULL) return -1L;
+    }
+    if (offset && s->back != EOF) {
+        s->back = EOF;
+        s->out++;
+        offset--;
+        if (s->last) s->z_err = Z_STREAM_END;
+    }
+    while (offset > 0)  {
+        int size = Z_BUFSIZE;
+        if (offset < Z_BUFSIZE) size = (int)offset;
+
+        size = gzread(file, s->outbuf, (uInt)size);
+        if (size <= 0) return -1L;
+        offset -= size;
+    }
+    return s->out;
+}
+
+/* ===========================================================================
+     Rewinds input file.
+*/
+int ZEXPORT gzrewind (file)
+    gzFile file;
+{
+    gz_stream *s = (gz_stream*)file;
+
+    if (s == NULL || s->mode != 'r') return -1;
+
+    s->z_err = Z_OK;
+    s->z_eof = 0;
+    s->back = EOF;
+    s->stream.avail_in = 0;
+    s->stream.next_in = s->inbuf;
+    s->crc = crc32(0L, Z_NULL, 0);
+    if (!s->transparent) (void)inflateReset(&s->stream);
+    s->in = 0;
+    s->out = 0;
+    return fseek(s->file, s->start, SEEK_SET);
+}
+
+/* ===========================================================================
+     Returns the starting position for the next gzread or gzwrite on the
+   given compressed file. This position represents a number of bytes in the
+   uncompressed data stream.
+*/
+z_off_t ZEXPORT gztell (file)
+    gzFile file;
+{
+    return gzseek(file, 0L, SEEK_CUR);
+}
+
+/* ===========================================================================
+     Returns 1 when EOF has previously been detected reading the given
+   input stream, otherwise zero.
+*/
+int ZEXPORT gzeof (file)
+    gzFile file;
+{
+    gz_stream *s = (gz_stream*)file;
+
+    /* With concatenated compressed files that can have embedded
+     * crc trailers, z_eof is no longer the only/best indicator of EOF
+     * on a gz_stream. Handle end-of-stream error explicitly here.
+     */
+    if (s == NULL || s->mode != 'r') return 0;
+    if (s->z_eof) return 1;
+    return s->z_err == Z_STREAM_END;
+}
+
+/* ===========================================================================
+     Returns 1 if reading and doing so transparently, otherwise zero.
+*/
+int ZEXPORT gzdirect (file)
+    gzFile file;
+{
+    gz_stream *s = (gz_stream*)file;
+
+    if (s == NULL || s->mode != 'r') return 0;
+    return s->transparent;
+}
+
+/* ===========================================================================
+   Outputs a long in LSB order to the given file
+*/
+local void putLong (file, x)
+    FILE *file;
+    uLong x;
+{
+    int n;
+    for (n = 0; n < 4; n++) {
+        fputc((int)(x & 0xff), file);
+        x >>= 8;
+    }
+}
+
+/* ===========================================================================
+   Reads a long in LSB order from the given gz_stream. Sets z_err in case
+   of error.
+*/
+local uLong getLong (s)
+    gz_stream *s;
+{
+    uLong x = (uLong)get_byte(s);
+    int c;
+
+    x += ((uLong)get_byte(s))<<8;
+    x += ((uLong)get_byte(s))<<16;
+    c = get_byte(s);
+    if (c == EOF) s->z_err = Z_DATA_ERROR;
+    x += ((uLong)c)<<24;
+    return x;
+}
+
+/* ===========================================================================
+     Flushes all pending output if necessary, closes the compressed file
+   and deallocates all the (de)compression state.
+*/
+int ZEXPORT gzclose (file)
+    gzFile file;
+{
+    gz_stream *s = (gz_stream*)file;
+
+    if (s == NULL) return Z_STREAM_ERROR;
+
+    if (s->mode == 'w') {
+#ifdef NO_GZCOMPRESS
+        return Z_STREAM_ERROR;
+#else
+        if (do_flush (file, Z_FINISH) != Z_OK)
+            return destroy((gz_stream*)file);
+
+        putLong (s->file, s->crc);
+        putLong (s->file, (uLong)(s->in & 0xffffffff));
+#endif
+    }
+    return destroy((gz_stream*)file);
+}
+
+#ifdef STDC
+#  define zstrerror(errnum) strerror(errnum)
+#else
+#  define zstrerror(errnum) ""
+#endif
+
+/* ===========================================================================
+     Returns the error message for the last error which occurred on the
+   given compressed file. errnum is set to zlib error number. If an
+   error occurred in the file system and not in the compression library,
+   errnum is set to Z_ERRNO and the application may consult errno
+   to get the exact error code.
+*/
+const char * ZEXPORT gzerror (file, errnum)
+    gzFile file;
+    int *errnum;
+{
+    char *m;
+    gz_stream *s = (gz_stream*)file;
+
+    if (s == NULL) {
+        *errnum = Z_STREAM_ERROR;
+        return (const char*)ERR_MSG(Z_STREAM_ERROR);
+    }
+    *errnum = s->z_err;
+    if (*errnum == Z_OK) return (const char*)"";
+
+    m = (char*)(*errnum == Z_ERRNO ? zstrerror(errno) : s->stream.msg);
+
+    if (m == NULL || *m == '\0') m = (char*)ERR_MSG(s->z_err);
+
+    TRYFREE(s->msg);
+    s->msg = (char*)ALLOC(strlen(s->path) + strlen(m) + 3);
+    if (s->msg == Z_NULL) return (const char*)ERR_MSG(Z_MEM_ERROR);
+    strcpy(s->msg, s->path);
+    strcat(s->msg, ": ");
+    strcat(s->msg, m);
+    return (const char*)s->msg;
+}
+
+/* ===========================================================================
+     Clear the error and end-of-file flags, and do the same for the real file.
+*/
+void ZEXPORT gzclearerr (file)
+    gzFile file;
+{
+    gz_stream *s = (gz_stream*)file;
+
+    if (s == NULL) return;
+    if (s->z_err != Z_STREAM_END) s->z_err = Z_OK;
+    s->z_eof = 0;
+    clearerr(s->file);
+}
diff --git a/gs/zlib/infback.c b/gs/zlib/infback.c
new file mode 100644
index 000000000..455dbc9ee
--- /dev/null
+++ b/gs/zlib/infback.c
@@ -0,0 +1,623 @@
+/* infback.c -- inflate using a call-back interface
+ * Copyright (C) 1995-2005 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/*
+   This code is largely copied from inflate.c.  Normally either infback.o or
+   inflate.o would be linked into an application--not both.  The interface
+   with inffast.c is retained so that optimized assembler-coded versions of
+   inflate_fast() can be used with either inflate.c or infback.c.
+ */
+
+#include "zutil.h"
+#include "inftrees.h"
+#include "inflate.h"
+#include "inffast.h"
+
+/* function prototypes */
+local void fixedtables OF((struct inflate_state FAR *state));
+
+/*
+   strm provides memory allocation functions in zalloc and zfree, or
+   Z_NULL to use the library memory allocation functions.
+
+   windowBits is in the range 8..15, and window is a user-supplied
+   window and output buffer that is 2**windowBits bytes.
+ */
+int ZEXPORT inflateBackInit_(strm, windowBits, window, version, stream_size)
+z_streamp strm;
+int windowBits;
+unsigned char FAR *window;
+const char *version;
+int stream_size;
+{
+    struct inflate_state FAR *state;
+
+    if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
+        stream_size != (int)(sizeof(z_stream)))
+        return Z_VERSION_ERROR;
+    if (strm == Z_NULL || window == Z_NULL ||
+        windowBits < 8 || windowBits > 15)
+        return Z_STREAM_ERROR;
+    strm->msg = Z_NULL;                 /* in case we return an error */
+    if (strm->zalloc == (alloc_func)0) {
+        strm->zalloc = zcalloc;
+        strm->opaque = (voidpf)0;
+    }
+    if (strm->zfree == (free_func)0) strm->zfree = zcfree;
+    state = (struct inflate_state FAR *)ZALLOC(strm, 1,
+                                               sizeof(struct inflate_state));
+    if (state == Z_NULL) return Z_MEM_ERROR;
+    Tracev((stderr, "inflate: allocated\n"));
+    strm->state = (struct internal_state FAR *)state;
+    state->dmax = 32768U;
+    state->wbits = windowBits;
+    state->wsize = 1U << windowBits;
+    state->window = window;
+    state->write = 0;
+    state->whave = 0;
+    return Z_OK;
+}
+
+/*
+   Return state with length and distance decoding tables and index sizes set to
+   fixed code decoding.  Normally this returns fixed tables from inffixed.h.
+   If BUILDFIXED is defined, then instead this routine builds the tables the
+   first time it's called, and returns those tables the first time and
+   thereafter.  This reduces the size of the code by about 2K bytes, in
+   exchange for a little execution time.  However, BUILDFIXED should not be
+   used for threaded applications, since the rewriting of the tables and virgin
+   may not be thread-safe.
+ */
+local void fixedtables(state)
+struct inflate_state FAR *state;
+{
+#ifdef BUILDFIXED
+    static int virgin = 1;
+    static code *lenfix, *distfix;
+    static code fixed[544];
+
+    /* build fixed huffman tables if first call (may not be thread safe) */
+    if (virgin) {
+        unsigned sym, bits;
+        static code *next;
+
+        /* literal/length table */
+        sym = 0;
+        while (sym < 144) state->lens[sym++] = 8;
+        while (sym < 256) state->lens[sym++] = 9;
+        while (sym < 280) state->lens[sym++] = 7;
+        while (sym < 288) state->lens[sym++] = 8;
+        next = fixed;
+        lenfix = next;
+        bits = 9;
+        inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work);
+
+        /* distance table */
+        sym = 0;
+        while (sym < 32) state->lens[sym++] = 5;
+        distfix = next;
+        bits = 5;
+        inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work);
+
+        /* do this just once */
+        virgin = 0;
+    }
+#else /* !BUILDFIXED */
+#   include "inffixed.h"
+#endif /* BUILDFIXED */
+    state->lencode = lenfix;
+    state->lenbits = 9;
+    state->distcode = distfix;
+    state->distbits = 5;
+}
+
+/* Macros for inflateBack(): */
+
+/* Load returned state from inflate_fast() */
+#define LOAD() \
+    do { \
+        put = strm->next_out; \
+        left = strm->avail_out; \
+        next = strm->next_in; \
+        have = strm->avail_in; \
+        hold = state->hold; \
+        bits = state->bits; \
+    } while (0)
+
+/* Set state from registers for inflate_fast() */
+#define RESTORE() \
+    do { \
+        strm->next_out = put; \
+        strm->avail_out = left; \
+        strm->next_in = next; \
+        strm->avail_in = have; \
+        state->hold = hold; \
+        state->bits = bits; \
+    } while (0)
+
+/* Clear the input bit accumulator */
+#define INITBITS() \
+    do { \
+        hold = 0; \
+        bits = 0; \
+    } while (0)
+
+/* Assure that some input is available.  If input is requested, but denied,
+   then return a Z_BUF_ERROR from inflateBack(). */
+#define PULL() \
+    do { \
+        if (have == 0) { \
+            have = in(in_desc, &next); \
+            if (have == 0) { \
+                next = Z_NULL; \
+                ret = Z_BUF_ERROR; \
+                goto inf_leave; \
+            } \
+        } \
+    } while (0)
+
+/* Get a byte of input into the bit accumulator, or return from inflateBack()
+   with an error if there is no input available. */
+#define PULLBYTE() \
+    do { \
+        PULL(); \
+        have--; \
+        hold += (unsigned long)(*next++) << bits; \
+        bits += 8; \
+    } while (0)
+
+/* Assure that there are at least n bits in the bit accumulator.  If there is
+   not enough available input to do that, then return from inflateBack() with
+   an error. */
+#define NEEDBITS(n) \
+    do { \
+        while (bits < (unsigned)(n)) \
+            PULLBYTE(); \
+    } while (0)
+
+/* Return the low n bits of the bit accumulator (n < 16) */
+#define BITS(n) \
+    ((unsigned)hold & ((1U << (n)) - 1))
+
+/* Remove n bits from the bit accumulator */
+#define DROPBITS(n) \
+    do { \
+        hold >>= (n); \
+        bits -= (unsigned)(n); \
+    } while (0)
+
+/* Remove zero to seven bits as needed to go to a byte boundary */
+#define BYTEBITS() \
+    do { \
+        hold >>= bits & 7; \
+        bits -= bits & 7; \
+    } while (0)
+
+/* Assure that some output space is available, by writing out the window
+   if it's full.  If the write fails, return from inflateBack() with a
+   Z_BUF_ERROR. */
+#define ROOM() \
+    do { \
+        if (left == 0) { \
+            put = state->window; \
+            left = state->wsize; \
+            state->whave = left; \
+            if (out(out_desc, put, left)) { \
+                ret = Z_BUF_ERROR; \
+                goto inf_leave; \
+            } \
+        } \
+    } while (0)
+
+/*
+   strm provides the memory allocation functions and window buffer on input,
+   and provides information on the unused input on return.  For Z_DATA_ERROR
+   returns, strm will also provide an error message.
+
+   in() and out() are the call-back input and output functions.  When
+   inflateBack() needs more input, it calls in().  When inflateBack() has
+   filled the window with output, or when it completes with data in the
+   window, it calls out() to write out the data.  The application must not
+   change the provided input until in() is called again or inflateBack()
+   returns.  The application must not change the window/output buffer until
+   inflateBack() returns.
+
+   in() and out() are called with a descriptor parameter provided in the
+   inflateBack() call.  This parameter can be a structure that provides the
+   information required to do the read or write, as well as accumulated
+   information on the input and output such as totals and check values.
+
+   in() should return zero on failure.  out() should return non-zero on
+   failure.  If either in() or out() fails, than inflateBack() returns a
+   Z_BUF_ERROR.  strm->next_in can be checked for Z_NULL to see whether it
+   was in() or out() that caused in the error.  Otherwise,  inflateBack()
+   returns Z_STREAM_END on success, Z_DATA_ERROR for an deflate format
+   error, or Z_MEM_ERROR if it could not allocate memory for the state.
+   inflateBack() can also return Z_STREAM_ERROR if the input parameters
+   are not correct, i.e. strm is Z_NULL or the state was not initialized.
+ */
+int ZEXPORT inflateBack(strm, in, in_desc, out, out_desc)
+z_streamp strm;
+in_func in;
+void FAR *in_desc;
+out_func out;
+void FAR *out_desc;
+{
+    struct inflate_state FAR *state;
+    unsigned char FAR *next;    /* next input */
+    unsigned char FAR *put;     /* next output */
+    unsigned have, left;        /* available input and output */
+    unsigned long hold;         /* bit buffer */
+    unsigned bits;              /* bits in bit buffer */
+    unsigned copy;              /* number of stored or match bytes to copy */
+    unsigned char FAR *from;    /* where to copy match bytes from */
+    code this;                  /* current decoding table entry */
+    code last;                  /* parent table entry */
+    unsigned len;               /* length to copy for repeats, bits to drop */
+    int ret;                    /* return code */
+    static const unsigned short order[19] = /* permutation of code lengths */
+        {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
+
+    /* Check that the strm exists and that the state was initialized */
+    if (strm == Z_NULL || strm->state == Z_NULL)
+        return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)strm->state;
+
+    /* Reset the state */
+    strm->msg = Z_NULL;
+    state->mode = TYPE;
+    state->last = 0;
+    state->whave = 0;
+    next = strm->next_in;
+    have = next != Z_NULL ? strm->avail_in : 0;
+    hold = 0;
+    bits = 0;
+    put = state->window;
+    left = state->wsize;
+
+    /* Inflate until end of block marked as last */
+    for (;;)
+        switch (state->mode) {
+        case TYPE:
+            /* determine and dispatch block type */
+            if (state->last) {
+                BYTEBITS();
+                state->mode = DONE;
+                break;
+            }
+            NEEDBITS(3);
+            state->last = BITS(1);
+            DROPBITS(1);
+            switch (BITS(2)) {
+            case 0:                             /* stored block */
+                Tracev((stderr, "inflate:     stored block%s\n",
+                        state->last ? " (last)" : ""));
+                state->mode = STORED;
+                break;
+            case 1:                             /* fixed block */
+                fixedtables(state);
+                Tracev((stderr, "inflate:     fixed codes block%s\n",
+                        state->last ? " (last)" : ""));
+                state->mode = LEN;              /* decode codes */
+                break;
+            case 2:                             /* dynamic block */
+                Tracev((stderr, "inflate:     dynamic codes block%s\n",
+                        state->last ? " (last)" : ""));
+                state->mode = TABLE;
+                break;
+            case 3:
+                strm->msg = (char *)"invalid block type";
+                state->mode = BAD;
+            }
+            DROPBITS(2);
+            break;
+
+        case STORED:
+            /* get and verify stored block length */
+            BYTEBITS();                         /* go to byte boundary */
+            NEEDBITS(32);
+            if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
+                strm->msg = (char *)"invalid stored block lengths";
+                state->mode = BAD;
+                break;
+            }
+            state->length = (unsigned)hold & 0xffff;
+            Tracev((stderr, "inflate:       stored length %u\n",
+                    state->length));
+            INITBITS();
+
+            /* copy stored block from input to output */
+            while (state->length != 0) {
+                copy = state->length;
+                PULL();
+                ROOM();
+                if (copy > have) copy = have;
+                if (copy > left) copy = left;
+                zmemcpy(put, next, copy);
+                have -= copy;
+                next += copy;
+                left -= copy;
+                put += copy;
+                state->length -= copy;
+            }
+            Tracev((stderr, "inflate:       stored end\n"));
+            state->mode = TYPE;
+            break;
+
+        case TABLE:
+            /* get dynamic table entries descriptor */
+            NEEDBITS(14);
+            state->nlen = BITS(5) + 257;
+            DROPBITS(5);
+            state->ndist = BITS(5) + 1;
+            DROPBITS(5);
+            state->ncode = BITS(4) + 4;
+            DROPBITS(4);
+#ifndef PKZIP_BUG_WORKAROUND
+            if (state->nlen > 286 || state->ndist > 30) {
+                strm->msg = (char *)"too many length or distance symbols";
+                state->mode = BAD;
+                break;
+            }
+#endif
+            Tracev((stderr, "inflate:       table sizes ok\n"));
+
+            /* get code length code lengths (not a typo) */
+            state->have = 0;
+            while (state->have < state->ncode) {
+                NEEDBITS(3);
+                state->lens[order[state->have++]] = (unsigned short)BITS(3);
+                DROPBITS(3);
+            }
+            while (state->have < 19)
+                state->lens[order[state->have++]] = 0;
+            state->next = state->codes;
+            state->lencode = (code const FAR *)(state->next);
+            state->lenbits = 7;
+            ret = inflate_table(CODES, state->lens, 19, &(state->next),
+                                &(state->lenbits), state->work);
+            if (ret) {
+                strm->msg = (char *)"invalid code lengths set";
+                state->mode = BAD;
+                break;
+            }
+            Tracev((stderr, "inflate:       code lengths ok\n"));
+
+            /* get length and distance code code lengths */
+            state->have = 0;
+            while (state->have < state->nlen + state->ndist) {
+                for (;;) {
+                    this = state->lencode[BITS(state->lenbits)];
+                    if ((unsigned)(this.bits) <= bits) break;
+                    PULLBYTE();
+                }
+                if (this.val < 16) {
+                    NEEDBITS(this.bits);
+                    DROPBITS(this.bits);
+                    state->lens[state->have++] = this.val;
+                }
+                else {
+                    if (this.val == 16) {
+                        NEEDBITS(this.bits + 2);
+                        DROPBITS(this.bits);
+                        if (state->have == 0) {
+                            strm->msg = (char *)"invalid bit length repeat";
+                            state->mode = BAD;
+                            break;
+                        }
+                        len = (unsigned)(state->lens[state->have - 1]);
+                        copy = 3 + BITS(2);
+                        DROPBITS(2);
+                    }
+                    else if (this.val == 17) {
+                        NEEDBITS(this.bits + 3);
+                        DROPBITS(this.bits);
+                        len = 0;
+                        copy = 3 + BITS(3);
+                        DROPBITS(3);
+                    }
+                    else {
+                        NEEDBITS(this.bits + 7);
+                        DROPBITS(this.bits);
+                        len = 0;
+                        copy = 11 + BITS(7);
+                        DROPBITS(7);
+                    }
+                    if (state->have + copy > state->nlen + state->ndist) {
+                        strm->msg = (char *)"invalid bit length repeat";
+                        state->mode = BAD;
+                        break;
+                    }
+                    while (copy--)
+                        state->lens[state->have++] = (unsigned short)len;
+                }
+            }
+
+            /* handle error breaks in while */
+            if (state->mode == BAD) break;
+
+            /* build code tables */
+            state->next = state->codes;
+            state->lencode = (code const FAR *)(state->next);
+            state->lenbits = 9;
+            ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
+                                &(state->lenbits), state->work);
+            if (ret) {
+                strm->msg = (char *)"invalid literal/lengths set";
+                state->mode = BAD;
+                break;
+            }
+            state->distcode = (code const FAR *)(state->next);
+            state->distbits = 6;
+            ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist,
+                            &(state->next), &(state->distbits), state->work);
+            if (ret) {
+                strm->msg = (char *)"invalid distances set";
+                state->mode = BAD;
+                break;
+            }
+            Tracev((stderr, "inflate:       codes ok\n"));
+            state->mode = LEN;
+
+        case LEN:
+            /* use inflate_fast() if we have enough input and output */
+            if (have >= 6 && left >= 258) {
+                RESTORE();
+                if (state->whave < state->wsize)
+                    state->whave = state->wsize - left;
+                inflate_fast(strm, state->wsize);
+                LOAD();
+                break;
+            }
+
+            /* get a literal, length, or end-of-block code */
+            for (;;) {
+                this = state->lencode[BITS(state->lenbits)];
+                if ((unsigned)(this.bits) <= bits) break;
+                PULLBYTE();
+            }
+            if (this.op && (this.op & 0xf0) == 0) {
+                last = this;
+                for (;;) {
+                    this = state->lencode[last.val +
+                            (BITS(last.bits + last.op) >> last.bits)];
+                    if ((unsigned)(last.bits + this.bits) <= bits) break;
+                    PULLBYTE();
+                }
+                DROPBITS(last.bits);
+            }
+            DROPBITS(this.bits);
+            state->length = (unsigned)this.val;
+
+            /* process literal */
+            if (this.op == 0) {
+                Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ?
+                        "inflate:         literal '%c'\n" :
+                        "inflate:         literal 0x%02x\n", this.val));
+                ROOM();
+                *put++ = (unsigned char)(state->length);
+                left--;
+                state->mode = LEN;
+                break;
+            }
+
+            /* process end of block */
+            if (this.op & 32) {
+                Tracevv((stderr, "inflate:         end of block\n"));
+                state->mode = TYPE;
+                break;
+            }
+
+            /* invalid code */
+            if (this.op & 64) {
+                strm->msg = (char *)"invalid literal/length code";
+                state->mode = BAD;
+                break;
+            }
+
+            /* length code -- get extra bits, if any */
+            state->extra = (unsigned)(this.op) & 15;
+            if (state->extra != 0) {
+                NEEDBITS(state->extra);
+                state->length += BITS(state->extra);
+                DROPBITS(state->extra);
+            }
+            Tracevv((stderr, "inflate:         length %u\n", state->length));
+
+            /* get distance code */
+            for (;;) {
+                this = state->distcode[BITS(state->distbits)];
+                if ((unsigned)(this.bits) <= bits) break;
+                PULLBYTE();
+            }
+            if ((this.op & 0xf0) == 0) {
+                last = this;
+                for (;;) {
+                    this = state->distcode[last.val +
+                            (BITS(last.bits + last.op) >> last.bits)];
+                    if ((unsigned)(last.bits + this.bits) <= bits) break;
+                    PULLBYTE();
+                }
+                DROPBITS(last.bits);
+            }
+            DROPBITS(this.bits);
+            if (this.op & 64) {
+                strm->msg = (char *)"invalid distance code";
+                state->mode = BAD;
+                break;
+            }
+            state->offset = (unsigned)this.val;
+
+            /* get distance extra bits, if any */
+            state->extra = (unsigned)(this.op) & 15;
+            if (state->extra != 0) {
+                NEEDBITS(state->extra);
+                state->offset += BITS(state->extra);
+                DROPBITS(state->extra);
+            }
+            if (state->offset > state->wsize - (state->whave < state->wsize ?
+                                                left : 0)) {
+                strm->msg = (char *)"invalid distance too far back";
+                state->mode = BAD;
+                break;
+            }
+            Tracevv((stderr, "inflate:         distance %u\n", state->offset));
+
+            /* copy match from window to output */
+            do {
+                ROOM();
+                copy = state->wsize - state->offset;
+                if (copy < left) {
+                    from = put + copy;
+                    copy = left - copy;
+                }
+                else {
+                    from = put - state->offset;
+                    copy = left;
+                }
+                if (copy > state->length) copy = state->length;
+                state->length -= copy;
+                left -= copy;
+                do {
+                    *put++ = *from++;
+                } while (--copy);
+            } while (state->length != 0);
+            break;
+
+        case DONE:
+            /* inflate stream terminated properly -- write leftover output */
+            ret = Z_STREAM_END;
+            if (left < state->wsize) {
+                if (out(out_desc, state->window, state->wsize - left))
+                    ret = Z_BUF_ERROR;
+            }
+            goto inf_leave;
+
+        case BAD:
+            ret = Z_DATA_ERROR;
+            goto inf_leave;
+
+        default:                /* can't happen, but makes compilers happy */
+            ret = Z_STREAM_ERROR;
+            goto inf_leave;
+        }
+
+    /* Return unused input */
+  inf_leave:
+    strm->next_in = next;
+    strm->avail_in = have;
+    return ret;
+}
+
+int ZEXPORT inflateBackEnd(strm)
+z_streamp strm;
+{
+    if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0)
+        return Z_STREAM_ERROR;
+    ZFREE(strm, strm->state);
+    strm->state = Z_NULL;
+    Tracev((stderr, "inflate: end\n"));
+    return Z_OK;
+}
diff --git a/gs/zlib/inffast.c b/gs/zlib/inffast.c
new file mode 100644
index 000000000..bbee92ed1
--- /dev/null
+++ b/gs/zlib/inffast.c
@@ -0,0 +1,318 @@
+/* inffast.c -- fast decoding
+ * Copyright (C) 1995-2004 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#include "zutil.h"
+#include "inftrees.h"
+#include "inflate.h"
+#include "inffast.h"
+
+#ifndef ASMINF
+
+/* Allow machine dependent optimization for post-increment or pre-increment.
+   Based on testing to date,
+   Pre-increment preferred for:
+   - PowerPC G3 (Adler)
+   - MIPS R5000 (Randers-Pehrson)
+   Post-increment preferred for:
+   - none
+   No measurable difference:
+   - Pentium III (Anderson)
+   - M68060 (Nikl)
+ */
+#ifdef POSTINC
+#  define OFF 0
+#  define PUP(a) *(a)++
+#else
+#  define OFF 1
+#  define PUP(a) *++(a)
+#endif
+
+/*
+   Decode literal, length, and distance codes and write out the resulting
+   literal and match bytes until either not enough input or output is
+   available, an end-of-block is encountered, or a data error is encountered.
+   When large enough input and output buffers are supplied to inflate(), for
+   example, a 16K input buffer and a 64K output buffer, more than 95% of the
+   inflate execution time is spent in this routine.
+
+   Entry assumptions:
+
+        state->mode == LEN
+        strm->avail_in >= 6
+        strm->avail_out >= 258
+        start >= strm->avail_out
+        state->bits < 8
+
+   On return, state->mode is one of:
+
+        LEN -- ran out of enough output space or enough available input
+        TYPE -- reached end of block code, inflate() to interpret next block
+        BAD -- error in block data
+
+   Notes:
+
+    - The maximum input bits used by a length/distance pair is 15 bits for the
+      length code, 5 bits for the length extra, 15 bits for the distance code,
+      and 13 bits for the distance extra.  This totals 48 bits, or six bytes.
+      Therefore if strm->avail_in >= 6, then there is enough input to avoid
+      checking for available input while decoding.
+
+    - The maximum bytes that a single length/distance pair can output is 258
+      bytes, which is the maximum length that can be coded.  inflate_fast()
+      requires strm->avail_out >= 258 for each loop to avoid checking for
+      output space.
+ */
+void inflate_fast(strm, start)
+z_streamp strm;
+unsigned start;         /* inflate()'s starting value for strm->avail_out */
+{
+    struct inflate_state FAR *state;
+    unsigned char FAR *in;      /* local strm->next_in */
+    unsigned char FAR *last;    /* while in < last, enough input available */
+    unsigned char FAR *out;     /* local strm->next_out */
+    unsigned char FAR *beg;     /* inflate()'s initial strm->next_out */
+    unsigned char FAR *end;     /* while out < end, enough space available */
+#ifdef INFLATE_STRICT
+    unsigned dmax;              /* maximum distance from zlib header */
+#endif
+    unsigned wsize;             /* window size or zero if not using window */
+    unsigned whave;             /* valid bytes in the window */
+    unsigned write;             /* window write index */
+    unsigned char FAR *window;  /* allocated sliding window, if wsize != 0 */
+    unsigned long hold;         /* local strm->hold */
+    unsigned bits;              /* local strm->bits */
+    code const FAR *lcode;      /* local strm->lencode */
+    code const FAR *dcode;      /* local strm->distcode */
+    unsigned lmask;             /* mask for first level of length codes */
+    unsigned dmask;             /* mask for first level of distance codes */
+    code this;                  /* retrieved table entry */
+    unsigned op;                /* code bits, operation, extra bits, or */
+                                /*  window position, window bytes to copy */
+    unsigned len;               /* match length, unused bytes */
+    unsigned dist;              /* match distance */
+    unsigned char FAR *from;    /* where to copy match from */
+
+    /* copy state to local variables */
+    state = (struct inflate_state FAR *)strm->state;
+    in = strm->next_in - OFF;
+    last = in + (strm->avail_in - 5);
+    out = strm->next_out - OFF;
+    beg = out - (start - strm->avail_out);
+    end = out + (strm->avail_out - 257);
+#ifdef INFLATE_STRICT
+    dmax = state->dmax;
+#endif
+    wsize = state->wsize;
+    whave = state->whave;
+    write = state->write;
+    window = state->window;
+    hold = state->hold;
+    bits = state->bits;
+    lcode = state->lencode;
+    dcode = state->distcode;
+    lmask = (1U << state->lenbits) - 1;
+    dmask = (1U << state->distbits) - 1;
+
+    /* decode literals and length/distances until end-of-block or not enough
+       input data or output space */
+    do {
+        if (bits < 15) {
+            hold += (unsigned long)(PUP(in)) << bits;
+            bits += 8;
+            hold += (unsigned long)(PUP(in)) << bits;
+            bits += 8;
+        }
+        this = lcode[hold & lmask];
+      dolen:
+        op = (unsigned)(this.bits);
+        hold >>= op;
+        bits -= op;
+        op = (unsigned)(this.op);
+        if (op == 0) {                          /* literal */
+            Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ?
+                    "inflate:         literal '%c'\n" :
+                    "inflate:         literal 0x%02x\n", this.val));
+            PUP(out) = (unsigned char)(this.val);
+        }
+        else if (op & 16) {                     /* length base */
+            len = (unsigned)(this.val);
+            op &= 15;                           /* number of extra bits */
+            if (op) {
+                if (bits < op) {
+                    hold += (unsigned long)(PUP(in)) << bits;
+                    bits += 8;
+                }
+                len += (unsigned)hold & ((1U << op) - 1);
+                hold >>= op;
+                bits -= op;
+            }
+            Tracevv((stderr, "inflate:         length %u\n", len));
+            if (bits < 15) {
+                hold += (unsigned long)(PUP(in)) << bits;
+                bits += 8;
+                hold += (unsigned long)(PUP(in)) << bits;
+                bits += 8;
+            }
+            this = dcode[hold & dmask];
+          dodist:
+            op = (unsigned)(this.bits);
+            hold >>= op;
+            bits -= op;
+            op = (unsigned)(this.op);
+            if (op & 16) {                      /* distance base */
+                dist = (unsigned)(this.val);
+                op &= 15;                       /* number of extra bits */
+                if (bits < op) {
+                    hold += (unsigned long)(PUP(in)) << bits;
+                    bits += 8;
+                    if (bits < op) {
+                        hold += (unsigned long)(PUP(in)) << bits;
+                        bits += 8;
+                    }
+                }
+                dist += (unsigned)hold & ((1U << op) - 1);
+#ifdef INFLATE_STRICT
+                if (dist > dmax) {
+                    strm->msg = (char *)"invalid distance too far back";
+                    state->mode = BAD;
+                    break;
+                }
+#endif
+                hold >>= op;
+                bits -= op;
+                Tracevv((stderr, "inflate:         distance %u\n", dist));
+                op = (unsigned)(out - beg);     /* max distance in output */
+                if (dist > op) {                /* see if copy from window */
+                    op = dist - op;             /* distance back in window */
+                    if (op > whave) {
+                        strm->msg = (char *)"invalid distance too far back";
+                        state->mode = BAD;
+                        break;
+                    }
+                    from = window - OFF;
+                    if (write == 0) {           /* very common case */
+                        from += wsize - op;
+                        if (op < len) {         /* some from window */
+                            len -= op;
+                            do {
+                                PUP(out) = PUP(from);
+                            } while (--op);
+                            from = out - dist;  /* rest from output */
+                        }
+                    }
+                    else if (write < op) {      /* wrap around window */
+                        from += wsize + write - op;
+                        op -= write;
+                        if (op < len) {         /* some from end of window */
+                            len -= op;
+                            do {
+                                PUP(out) = PUP(from);
+                            } while (--op);
+                            from = window - OFF;
+                            if (write < len) {  /* some from start of window */
+                                op = write;
+                                len -= op;
+                                do {
+                                    PUP(out) = PUP(from);
+                                } while (--op);
+                                from = out - dist;      /* rest from output */
+                            }
+                        }
+                    }
+                    else {                      /* contiguous in window */
+                        from += write - op;
+                        if (op < len) {         /* some from window */
+                            len -= op;
+                            do {
+                                PUP(out) = PUP(from);
+                            } while (--op);
+                            from = out - dist;  /* rest from output */
+                        }
+                    }
+                    while (len > 2) {
+                        PUP(out) = PUP(from);
+                        PUP(out) = PUP(from);
+                        PUP(out) = PUP(from);
+                        len -= 3;
+                    }
+                    if (len) {
+                        PUP(out) = PUP(from);
+                        if (len > 1)
+                            PUP(out) = PUP(from);
+                    }
+                }
+                else {
+                    from = out - dist;          /* copy direct from output */
+                    do {                        /* minimum length is three */
+                        PUP(out) = PUP(from);
+                        PUP(out) = PUP(from);
+                        PUP(out) = PUP(from);
+                        len -= 3;
+                    } while (len > 2);
+                    if (len) {
+                        PUP(out) = PUP(from);
+                        if (len > 1)
+                            PUP(out) = PUP(from);
+                    }
+                }
+            }
+            else if ((op & 64) == 0) {          /* 2nd level distance code */
+                this = dcode[this.val + (hold & ((1U << op) - 1))];
+                goto dodist;
+            }
+            else {
+                strm->msg = (char *)"invalid distance code";
+                state->mode = BAD;
+                break;
+            }
+        }
+        else if ((op & 64) == 0) {              /* 2nd level length code */
+            this = lcode[this.val + (hold & ((1U << op) - 1))];
+            goto dolen;
+        }
+        else if (op & 32) {                     /* end-of-block */
+            Tracevv((stderr, "inflate:         end of block\n"));
+            state->mode = TYPE;
+            break;
+        }
+        else {
+            strm->msg = (char *)"invalid literal/length code";
+            state->mode = BAD;
+            break;
+        }
+    } while (in < last && out < end);
+
+    /* return unused bytes (on entry, bits < 8, so in won't go too far back) */
+    len = bits >> 3;
+    in -= len;
+    bits -= len << 3;
+    hold &= (1U << bits) - 1;
+
+    /* update state and return */
+    strm->next_in = in + OFF;
+    strm->next_out = out + OFF;
+    strm->avail_in = (unsigned)(in < last ? 5 + (last - in) : 5 - (in - last));
+    strm->avail_out = (unsigned)(out < end ?
+                                 257 + (end - out) : 257 - (out - end));
+    state->hold = hold;
+    state->bits = bits;
+    return;
+}
+
+/*
+   inflate_fast() speedups that turned out slower (on a PowerPC G3 750CXe):
+   - Using bit fields for code structure
+   - Different op definition to avoid & for extra bits (do & for table bits)
+   - Three separate decoding do-loops for direct, window, and write == 0
+   - Special case for distance > 1 copies to do overlapped load and store copy
+   - Explicit branch predictions (based on measured branch probabilities)
+   - Deferring match copy and interspersed it with decoding subsequent codes
+   - Swapping literal/length else
+   - Swapping window/direct else
+   - Larger unrolled copy loops (three is about right)
+   - Moving len -= 3 statement into middle of loop
+ */
+
+#endif /* !ASMINF */
diff --git a/gs/zlib/inffast.h b/gs/zlib/inffast.h
new file mode 100644
index 000000000..1e88d2d97
--- /dev/null
+++ b/gs/zlib/inffast.h
@@ -0,0 +1,11 @@
+/* inffast.h -- header to use inffast.c
+ * Copyright (C) 1995-2003 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* WARNING: this file should *not* be used by applications. It is
+   part of the implementation of the compression library and is
+   subject to change. Applications should only use zlib.h.
+ */
+
+void inflate_fast OF((z_streamp strm, unsigned start));
diff --git a/gs/zlib/inffixed.h b/gs/zlib/inffixed.h
new file mode 100644
index 000000000..75ed4b597
--- /dev/null
+++ b/gs/zlib/inffixed.h
@@ -0,0 +1,94 @@
+    /* inffixed.h -- table for decoding fixed codes
+     * Generated automatically by makefixed().
+     */
+
+    /* WARNING: this file should *not* be used by applications. It
+       is part of the implementation of the compression library and
+       is subject to change. Applications should only use zlib.h.
+     */
+
+    static const code lenfix[512] = {
+        {96,7,0},{0,8,80},{0,8,16},{20,8,115},{18,7,31},{0,8,112},{0,8,48},
+        {0,9,192},{16,7,10},{0,8,96},{0,8,32},{0,9,160},{0,8,0},{0,8,128},
+        {0,8,64},{0,9,224},{16,7,6},{0,8,88},{0,8,24},{0,9,144},{19,7,59},
+        {0,8,120},{0,8,56},{0,9,208},{17,7,17},{0,8,104},{0,8,40},{0,9,176},
+        {0,8,8},{0,8,136},{0,8,72},{0,9,240},{16,7,4},{0,8,84},{0,8,20},
+        {21,8,227},{19,7,43},{0,8,116},{0,8,52},{0,9,200},{17,7,13},{0,8,100},
+        {0,8,36},{0,9,168},{0,8,4},{0,8,132},{0,8,68},{0,9,232},{16,7,8},
+        {0,8,92},{0,8,28},{0,9,152},{20,7,83},{0,8,124},{0,8,60},{0,9,216},
+        {18,7,23},{0,8,108},{0,8,44},{0,9,184},{0,8,12},{0,8,140},{0,8,76},
+        {0,9,248},{16,7,3},{0,8,82},{0,8,18},{21,8,163},{19,7,35},{0,8,114},
+        {0,8,50},{0,9,196},{17,7,11},{0,8,98},{0,8,34},{0,9,164},{0,8,2},
+        {0,8,130},{0,8,66},{0,9,228},{16,7,7},{0,8,90},{0,8,26},{0,9,148},
+        {20,7,67},{0,8,122},{0,8,58},{0,9,212},{18,7,19},{0,8,106},{0,8,42},
+        {0,9,180},{0,8,10},{0,8,138},{0,8,74},{0,9,244},{16,7,5},{0,8,86},
+        {0,8,22},{64,8,0},{19,7,51},{0,8,118},{0,8,54},{0,9,204},{17,7,15},
+        {0,8,102},{0,8,38},{0,9,172},{0,8,6},{0,8,134},{0,8,70},{0,9,236},
+        {16,7,9},{0,8,94},{0,8,30},{0,9,156},{20,7,99},{0,8,126},{0,8,62},
+        {0,9,220},{18,7,27},{0,8,110},{0,8,46},{0,9,188},{0,8,14},{0,8,142},
+        {0,8,78},{0,9,252},{96,7,0},{0,8,81},{0,8,17},{21,8,131},{18,7,31},
+        {0,8,113},{0,8,49},{0,9,194},{16,7,10},{0,8,97},{0,8,33},{0,9,162},
+        {0,8,1},{0,8,129},{0,8,65},{0,9,226},{16,7,6},{0,8,89},{0,8,25},
+        {0,9,146},{19,7,59},{0,8,121},{0,8,57},{0,9,210},{17,7,17},{0,8,105},
+        {0,8,41},{0,9,178},{0,8,9},{0,8,137},{0,8,73},{0,9,242},{16,7,4},
+        {0,8,85},{0,8,21},{16,8,258},{19,7,43},{0,8,117},{0,8,53},{0,9,202},
+        {17,7,13},{0,8,101},{0,8,37},{0,9,170},{0,8,5},{0,8,133},{0,8,69},
+        {0,9,234},{16,7,8},{0,8,93},{0,8,29},{0,9,154},{20,7,83},{0,8,125},
+        {0,8,61},{0,9,218},{18,7,23},{0,8,109},{0,8,45},{0,9,186},{0,8,13},
+        {0,8,141},{0,8,77},{0,9,250},{16,7,3},{0,8,83},{0,8,19},{21,8,195},
+        {19,7,35},{0,8,115},{0,8,51},{0,9,198},{17,7,11},{0,8,99},{0,8,35},
+        {0,9,166},{0,8,3},{0,8,131},{0,8,67},{0,9,230},{16,7,7},{0,8,91},
+        {0,8,27},{0,9,150},{20,7,67},{0,8,123},{0,8,59},{0,9,214},{18,7,19},
+        {0,8,107},{0,8,43},{0,9,182},{0,8,11},{0,8,139},{0,8,75},{0,9,246},
+        {16,7,5},{0,8,87},{0,8,23},{64,8,0},{19,7,51},{0,8,119},{0,8,55},
+        {0,9,206},{17,7,15},{0,8,103},{0,8,39},{0,9,174},{0,8,7},{0,8,135},
+        {0,8,71},{0,9,238},{16,7,9},{0,8,95},{0,8,31},{0,9,158},{20,7,99},
+        {0,8,127},{0,8,63},{0,9,222},{18,7,27},{0,8,111},{0,8,47},{0,9,190},
+        {0,8,15},{0,8,143},{0,8,79},{0,9,254},{96,7,0},{0,8,80},{0,8,16},
+        {20,8,115},{18,7,31},{0,8,112},{0,8,48},{0,9,193},{16,7,10},{0,8,96},
+        {0,8,32},{0,9,161},{0,8,0},{0,8,128},{0,8,64},{0,9,225},{16,7,6},
+        {0,8,88},{0,8,24},{0,9,145},{19,7,59},{0,8,120},{0,8,56},{0,9,209},
+        {17,7,17},{0,8,104},{0,8,40},{0,9,177},{0,8,8},{0,8,136},{0,8,72},
+        {0,9,241},{16,7,4},{0,8,84},{0,8,20},{21,8,227},{19,7,43},{0,8,116},
+        {0,8,52},{0,9,201},{17,7,13},{0,8,100},{0,8,36},{0,9,169},{0,8,4},
+        {0,8,132},{0,8,68},{0,9,233},{16,7,8},{0,8,92},{0,8,28},{0,9,153},
+        {20,7,83},{0,8,124},{0,8,60},{0,9,217},{18,7,23},{0,8,108},{0,8,44},
+        {0,9,185},{0,8,12},{0,8,140},{0,8,76},{0,9,249},{16,7,3},{0,8,82},
+        {0,8,18},{21,8,163},{19,7,35},{0,8,114},{0,8,50},{0,9,197},{17,7,11},
+        {0,8,98},{0,8,34},{0,9,165},{0,8,2},{0,8,130},{0,8,66},{0,9,229},
+        {16,7,7},{0,8,90},{0,8,26},{0,9,149},{20,7,67},{0,8,122},{0,8,58},
+        {0,9,213},{18,7,19},{0,8,106},{0,8,42},{0,9,181},{0,8,10},{0,8,138},
+        {0,8,74},{0,9,245},{16,7,5},{0,8,86},{0,8,22},{64,8,0},{19,7,51},
+        {0,8,118},{0,8,54},{0,9,205},{17,7,15},{0,8,102},{0,8,38},{0,9,173},
+        {0,8,6},{0,8,134},{0,8,70},{0,9,237},{16,7,9},{0,8,94},{0,8,30},
+        {0,9,157},{20,7,99},{0,8,126},{0,8,62},{0,9,221},{18,7,27},{0,8,110},
+        {0,8,46},{0,9,189},{0,8,14},{0,8,142},{0,8,78},{0,9,253},{96,7,0},
+        {0,8,81},{0,8,17},{21,8,131},{18,7,31},{0,8,113},{0,8,49},{0,9,195},
+        {16,7,10},{0,8,97},{0,8,33},{0,9,163},{0,8,1},{0,8,129},{0,8,65},
+        {0,9,227},{16,7,6},{0,8,89},{0,8,25},{0,9,147},{19,7,59},{0,8,121},
+        {0,8,57},{0,9,211},{17,7,17},{0,8,105},{0,8,41},{0,9,179},{0,8,9},
+        {0,8,137},{0,8,73},{0,9,243},{16,7,4},{0,8,85},{0,8,21},{16,8,258},
+        {19,7,43},{0,8,117},{0,8,53},{0,9,203},{17,7,13},{0,8,101},{0,8,37},
+        {0,9,171},{0,8,5},{0,8,133},{0,8,69},{0,9,235},{16,7,8},{0,8,93},
+        {0,8,29},{0,9,155},{20,7,83},{0,8,125},{0,8,61},{0,9,219},{18,7,23},
+        {0,8,109},{0,8,45},{0,9,187},{0,8,13},{0,8,141},{0,8,77},{0,9,251},
+        {16,7,3},{0,8,83},{0,8,19},{21,8,195},{19,7,35},{0,8,115},{0,8,51},
+        {0,9,199},{17,7,11},{0,8,99},{0,8,35},{0,9,167},{0,8,3},{0,8,131},
+        {0,8,67},{0,9,231},{16,7,7},{0,8,91},{0,8,27},{0,9,151},{20,7,67},
+        {0,8,123},{0,8,59},{0,9,215},{18,7,19},{0,8,107},{0,8,43},{0,9,183},
+        {0,8,11},{0,8,139},{0,8,75},{0,9,247},{16,7,5},{0,8,87},{0,8,23},
+        {64,8,0},{19,7,51},{0,8,119},{0,8,55},{0,9,207},{17,7,15},{0,8,103},
+        {0,8,39},{0,9,175},{0,8,7},{0,8,135},{0,8,71},{0,9,239},{16,7,9},
+        {0,8,95},{0,8,31},{0,9,159},{20,7,99},{0,8,127},{0,8,63},{0,9,223},
+        {18,7,27},{0,8,111},{0,8,47},{0,9,191},{0,8,15},{0,8,143},{0,8,79},
+        {0,9,255}
+    };
+
+    static const code distfix[32] = {
+        {16,5,1},{23,5,257},{19,5,17},{27,5,4097},{17,5,5},{25,5,1025},
+        {21,5,65},{29,5,16385},{16,5,3},{24,5,513},{20,5,33},{28,5,8193},
+        {18,5,9},{26,5,2049},{22,5,129},{64,5,0},{16,5,2},{23,5,385},
+        {19,5,25},{27,5,6145},{17,5,7},{25,5,1537},{21,5,97},{29,5,24577},
+        {16,5,4},{24,5,769},{20,5,49},{28,5,12289},{18,5,13},{26,5,3073},
+        {22,5,193},{64,5,0}
+    };
diff --git a/gs/zlib/inflate.c b/gs/zlib/inflate.c
new file mode 100644
index 000000000..792fdee8e
--- /dev/null
+++ b/gs/zlib/inflate.c
@@ -0,0 +1,1368 @@
+/* inflate.c -- zlib decompression
+ * Copyright (C) 1995-2005 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/*
+ * Change history:
+ *
+ * 1.2.beta0    24 Nov 2002
+ * - First version -- complete rewrite of inflate to simplify code, avoid
+ *   creation of window when not needed, minimize use of window when it is
+ *   needed, make inffast.c even faster, implement gzip decoding, and to
+ *   improve code readability and style over the previous zlib inflate code
+ *
+ * 1.2.beta1    25 Nov 2002
+ * - Use pointers for available input and output checking in inffast.c
+ * - Remove input and output counters in inffast.c
+ * - Change inffast.c entry and loop from avail_in >= 7 to >= 6
+ * - Remove unnecessary second byte pull from length extra in inffast.c
+ * - Unroll direct copy to three copies per loop in inffast.c
+ *
+ * 1.2.beta2    4 Dec 2002
+ * - Change external routine names to reduce potential conflicts
+ * - Correct filename to inffixed.h for fixed tables in inflate.c
+ * - Make hbuf[] unsigned char to match parameter type in inflate.c
+ * - Change strm->next_out[-state->offset] to *(strm->next_out - state->offset)
+ *   to avoid negation problem on Alphas (64 bit) in inflate.c
+ *
+ * 1.2.beta3    22 Dec 2002
+ * - Add comments on state->bits assertion in inffast.c
+ * - Add comments on op field in inftrees.h
+ * - Fix bug in reuse of allocated window after inflateReset()
+ * - Remove bit fields--back to byte structure for speed
+ * - Remove distance extra == 0 check in inflate_fast()--only helps for lengths
+ * - Change post-increments to pre-increments in inflate_fast(), PPC biased?
+ * - Add compile time option, POSTINC, to use post-increments instead (Intel?)
+ * - Make MATCH copy in inflate() much faster for when inflate_fast() not used
+ * - Use local copies of stream next and avail values, as well as local bit
+ *   buffer and bit count in inflate()--for speed when inflate_fast() not used
+ *
+ * 1.2.beta4    1 Jan 2003
+ * - Split ptr - 257 statements in inflate_table() to avoid compiler warnings
+ * - Move a comment on output buffer sizes from inffast.c to inflate.c
+ * - Add comments in inffast.c to introduce the inflate_fast() routine
+ * - Rearrange window copies in inflate_fast() for speed and simplification
+ * - Unroll last copy for window match in inflate_fast()
+ * - Use local copies of window variables in inflate_fast() for speed
+ * - Pull out common write == 0 case for speed in inflate_fast()
+ * - Make op and len in inflate_fast() unsigned for consistency
+ * - Add FAR to lcode and dcode declarations in inflate_fast()
+ * - Simplified bad distance check in inflate_fast()
+ * - Added inflateBackInit(), inflateBack(), and inflateBackEnd() in new
+ *   source file infback.c to provide a call-back interface to inflate for
+ *   programs like gzip and unzip -- uses window as output buffer to avoid
+ *   window copying
+ *
+ * 1.2.beta5    1 Jan 2003
+ * - Improved inflateBack() interface to allow the caller to provide initial
+ *   input in strm.
+ * - Fixed stored blocks bug in inflateBack()
+ *
+ * 1.2.beta6    4 Jan 2003
+ * - Added comments in inffast.c on effectiveness of POSTINC
+ * - Typecasting all around to reduce compiler warnings
+ * - Changed loops from while (1) or do {} while (1) to for (;;), again to
+ *   make compilers happy
+ * - Changed type of window in inflateBackInit() to unsigned char *
+ *
+ * 1.2.beta7    27 Jan 2003
+ * - Changed many types to unsigned or unsigned short to avoid warnings
+ * - Added inflateCopy() function
+ *
+ * 1.2.0        9 Mar 2003
+ * - Changed inflateBack() interface to provide separate opaque descriptors
+ *   for the in() and out() functions
+ * - Changed inflateBack() argument and in_func typedef to swap the length
+ *   and buffer address return values for the input function
+ * - Check next_in and next_out for Z_NULL on entry to inflate()
+ *
+ * The history for versions after 1.2.0 are in ChangeLog in zlib distribution.
+ */
+
+#include "zutil.h"
+#include "inftrees.h"
+#include "inflate.h"
+#include "inffast.h"
+
+#ifdef MAKEFIXED
+#  ifndef BUILDFIXED
+#    define BUILDFIXED
+#  endif
+#endif
+
+/* function prototypes */
+local void fixedtables OF((struct inflate_state FAR *state));
+local int updatewindow OF((z_streamp strm, unsigned out));
+#ifdef BUILDFIXED
+   void makefixed OF((void));
+#endif
+local unsigned syncsearch OF((unsigned FAR *have, unsigned char FAR *buf,
+                              unsigned len));
+
+int ZEXPORT inflateReset(strm)
+z_streamp strm;
+{
+    struct inflate_state FAR *state;
+
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)strm->state;
+    strm->total_in = strm->total_out = state->total = 0;
+    strm->msg = Z_NULL;
+    strm->adler = 1;        /* to support ill-conceived Java test suite */
+    state->mode = HEAD;
+    state->last = 0;
+    state->havedict = 0;
+    state->dmax = 32768U;
+    state->head = Z_NULL;
+    state->wsize = 0;
+    state->whave = 0;
+    state->write = 0;
+    state->hold = 0;
+    state->bits = 0;
+    state->lencode = state->distcode = state->next = state->codes;
+    Tracev((stderr, "inflate: reset\n"));
+    return Z_OK;
+}
+
+int ZEXPORT inflatePrime(strm, bits, value)
+z_streamp strm;
+int bits;
+int value;
+{
+    struct inflate_state FAR *state;
+
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)strm->state;
+    if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR;
+    value &= (1L << bits) - 1;
+    state->hold += value << state->bits;
+    state->bits += bits;
+    return Z_OK;
+}
+
+int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size)
+z_streamp strm;
+int windowBits;
+const char *version;
+int stream_size;
+{
+    struct inflate_state FAR *state;
+
+    if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
+        stream_size != (int)(sizeof(z_stream)))
+        return Z_VERSION_ERROR;
+    if (strm == Z_NULL) return Z_STREAM_ERROR;
+    strm->msg = Z_NULL;                 /* in case we return an error */
+    if (strm->zalloc == (alloc_func)0) {
+        strm->zalloc = zcalloc;
+        strm->opaque = (voidpf)0;
+    }
+    if (strm->zfree == (free_func)0) strm->zfree = zcfree;
+    state = (struct inflate_state FAR *)
+            ZALLOC(strm, 1, sizeof(struct inflate_state));
+    if (state == Z_NULL) return Z_MEM_ERROR;
+    Tracev((stderr, "inflate: allocated\n"));
+    strm->state = (struct internal_state FAR *)state;
+    if (windowBits < 0) {
+        state->wrap = 0;
+        windowBits = -windowBits;
+    }
+    else {
+        state->wrap = (windowBits >> 4) + 1;
+#ifdef GUNZIP
+        if (windowBits < 48) windowBits &= 15;
+#endif
+    }
+    if (windowBits < 8 || windowBits > 15) {
+        ZFREE(strm, state);
+        strm->state = Z_NULL;
+        return Z_STREAM_ERROR;
+    }
+    state->wbits = (unsigned)windowBits;
+    state->window = Z_NULL;
+    return inflateReset(strm);
+}
+
+int ZEXPORT inflateInit_(strm, version, stream_size)
+z_streamp strm;
+const char *version;
+int stream_size;
+{
+    return inflateInit2_(strm, DEF_WBITS, version, stream_size);
+}
+
+/*
+   Return state with length and distance decoding tables and index sizes set to
+   fixed code decoding.  Normally this returns fixed tables from inffixed.h.
+   If BUILDFIXED is defined, then instead this routine builds the tables the
+   first time it's called, and returns those tables the first time and
+   thereafter.  This reduces the size of the code by about 2K bytes, in
+   exchange for a little execution time.  However, BUILDFIXED should not be
+   used for threaded applications, since the rewriting of the tables and virgin
+   may not be thread-safe.
+ */
+local void fixedtables(state)
+struct inflate_state FAR *state;
+{
+#ifdef BUILDFIXED
+    static int virgin = 1;
+    static code *lenfix, *distfix;
+    static code fixed[544];
+
+    /* build fixed huffman tables if first call (may not be thread safe) */
+    if (virgin) {
+        unsigned sym, bits;
+        static code *next;
+
+        /* literal/length table */
+        sym = 0;
+        while (sym < 144) state->lens[sym++] = 8;
+        while (sym < 256) state->lens[sym++] = 9;
+        while (sym < 280) state->lens[sym++] = 7;
+        while (sym < 288) state->lens[sym++] = 8;
+        next = fixed;
+        lenfix = next;
+        bits = 9;
+        inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work);
+
+        /* distance table */
+        sym = 0;
+        while (sym < 32) state->lens[sym++] = 5;
+        distfix = next;
+        bits = 5;
+        inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work);
+
+        /* do this just once */
+        virgin = 0;
+    }
+#else /* !BUILDFIXED */
+#   include "inffixed.h"
+#endif /* BUILDFIXED */
+    state->lencode = lenfix;
+    state->lenbits = 9;
+    state->distcode = distfix;
+    state->distbits = 5;
+}
+
+#ifdef MAKEFIXED
+#include <stdio.h>
+
+/*
+   Write out the inffixed.h that is #include'd above.  Defining MAKEFIXED also
+   defines BUILDFIXED, so the tables are built on the fly.  makefixed() writes
+   those tables to stdout, which would be piped to inffixed.h.  A small program
+   can simply call makefixed to do this:
+
+    void makefixed(void);
+
+    int main(void)
+    {
+        makefixed();
+        return 0;
+    }
+
+   Then that can be linked with zlib built with MAKEFIXED defined and run:
+
+    a.out > inffixed.h
+ */
+void makefixed()
+{
+    unsigned low, size;
+    struct inflate_state state;
+
+    fixedtables(&state);
+    puts("    /* inffixed.h -- table for decoding fixed codes");
+    puts("     * Generated automatically by makefixed().");
+    puts("     */");
+    puts("");
+    puts("    /* WARNING: this file should *not* be used by applications.");
+    puts("       It is part of the implementation of this library and is");
+    puts("       subject to change. Applications should only use zlib.h.");
+    puts("     */");
+    puts("");
+    size = 1U << 9;
+    printf("    static const code lenfix[%u] = {", size);
+    low = 0;
+    for (;;) {
+        if ((low % 7) == 0) printf("\n        ");
+        printf("{%u,%u,%d}", state.lencode[low].op, state.lencode[low].bits,
+               state.lencode[low].val);
+        if (++low == size) break;
+        putchar(',');
+    }
+    puts("\n    };");
+    size = 1U << 5;
+    printf("\n    static const code distfix[%u] = {", size);
+    low = 0;
+    for (;;) {
+        if ((low % 6) == 0) printf("\n        ");
+        printf("{%u,%u,%d}", state.distcode[low].op, state.distcode[low].bits,
+               state.distcode[low].val);
+        if (++low == size) break;
+        putchar(',');
+    }
+    puts("\n    };");
+}
+#endif /* MAKEFIXED */
+
+/*
+   Update the window with the last wsize (normally 32K) bytes written before
+   returning.  If window does not exist yet, create it.  This is only called
+   when a window is already in use, or when output has been written during this
+   inflate call, but the end of the deflate stream has not been reached yet.
+   It is also called to create a window for dictionary data when a dictionary
+   is loaded.
+
+   Providing output buffers larger than 32K to inflate() should provide a speed
+   advantage, since only the last 32K of output is copied to the sliding window
+   upon return from inflate(), and since all distances after the first 32K of
+   output will fall in the output data, making match copies simpler and faster.
+   The advantage may be dependent on the size of the processor's data caches.
+ */
+local int updatewindow(strm, out)
+z_streamp strm;
+unsigned out;
+{
+    struct inflate_state FAR *state;
+    unsigned copy, dist;
+
+    state = (struct inflate_state FAR *)strm->state;
+
+    /* if it hasn't been done already, allocate space for the window */
+    if (state->window == Z_NULL) {
+        state->window = (unsigned char FAR *)
+                        ZALLOC(strm, 1U << state->wbits,
+                               sizeof(unsigned char));
+        if (state->window == Z_NULL) return 1;
+    }
+
+    /* if window not in use yet, initialize */
+    if (state->wsize == 0) {
+        state->wsize = 1U << state->wbits;
+        state->write = 0;
+        state->whave = 0;
+    }
+
+    /* copy state->wsize or less output bytes into the circular window */
+    copy = out - strm->avail_out;
+    if (copy >= state->wsize) {
+        zmemcpy(state->window, strm->next_out - state->wsize, state->wsize);
+        state->write = 0;
+        state->whave = state->wsize;
+    }
+    else {
+        dist = state->wsize - state->write;
+        if (dist > copy) dist = copy;
+        zmemcpy(state->window + state->write, strm->next_out - copy, dist);
+        copy -= dist;
+        if (copy) {
+            zmemcpy(state->window, strm->next_out - copy, copy);
+            state->write = copy;
+            state->whave = state->wsize;
+        }
+        else {
+            state->write += dist;
+            if (state->write == state->wsize) state->write = 0;
+            if (state->whave < state->wsize) state->whave += dist;
+        }
+    }
+    return 0;
+}
+
+/* Macros for inflate(): */
+
+/* check function to use adler32() for zlib or crc32() for gzip */
+#ifdef GUNZIP
+#  define UPDATE(check, buf, len) \
+    (state->flags ? crc32(check, buf, len) : adler32(check, buf, len))
+#else
+#  define UPDATE(check, buf, len) adler32(check, buf, len)
+#endif
+
+/* check macros for header crc */
+#ifdef GUNZIP
+#  define CRC2(check, word) \
+    do { \
+        hbuf[0] = (unsigned char)(word); \
+        hbuf[1] = (unsigned char)((word) >> 8); \
+        check = crc32(check, hbuf, 2); \
+    } while (0)
+
+#  define CRC4(check, word) \
+    do { \
+        hbuf[0] = (unsigned char)(word); \
+        hbuf[1] = (unsigned char)((word) >> 8); \
+        hbuf[2] = (unsigned char)((word) >> 16); \
+        hbuf[3] = (unsigned char)((word) >> 24); \
+        check = crc32(check, hbuf, 4); \
+    } while (0)
+#endif
+
+/* Load registers with state in inflate() for speed */
+#define LOAD() \
+    do { \
+        put = strm->next_out; \
+        left = strm->avail_out; \
+        next = strm->next_in; \
+        have = strm->avail_in; \
+        hold = state->hold; \
+        bits = state->bits; \
+    } while (0)
+
+/* Restore state from registers in inflate() */
+#define RESTORE() \
+    do { \
+        strm->next_out = put; \
+        strm->avail_out = left; \
+        strm->next_in = next; \
+        strm->avail_in = have; \
+        state->hold = hold; \
+        state->bits = bits; \
+    } while (0)
+
+/* Clear the input bit accumulator */
+#define INITBITS() \
+    do { \
+        hold = 0; \
+        bits = 0; \
+    } while (0)
+
+/* Get a byte of input into the bit accumulator, or return from inflate()
+   if there is no input available. */
+#define PULLBYTE() \
+    do { \
+        if (have == 0) goto inf_leave; \
+        have--; \
+        hold += (unsigned long)(*next++) << bits; \
+        bits += 8; \
+    } while (0)
+
+/* Assure that there are at least n bits in the bit accumulator.  If there is
+   not enough available input to do that, then return from inflate(). */
+#define NEEDBITS(n) \
+    do { \
+        while (bits < (unsigned)(n)) \
+            PULLBYTE(); \
+    } while (0)
+
+/* Return the low n bits of the bit accumulator (n < 16) */
+#define BITS(n) \
+    ((unsigned)hold & ((1U << (n)) - 1))
+
+/* Remove n bits from the bit accumulator */
+#define DROPBITS(n) \
+    do { \
+        hold >>= (n); \
+        bits -= (unsigned)(n); \
+    } while (0)
+
+/* Remove zero to seven bits as needed to go to a byte boundary */
+#define BYTEBITS() \
+    do { \
+        hold >>= bits & 7; \
+        bits -= bits & 7; \
+    } while (0)
+
+/* Reverse the bytes in a 32-bit value */
+#define REVERSE(q) \
+    ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \
+     (((q) & 0xff00) << 8) + (((q) & 0xff) << 24))
+
+/*
+   inflate() uses a state machine to process as much input data and generate as
+   much output data as possible before returning.  The state machine is
+   structured roughly as follows:
+
+    for (;;) switch (state) {
+    ...
+    case STATEn:
+        if (not enough input data or output space to make progress)
+            return;
+        ... make progress ...
+        state = STATEm;
+        break;
+    ...
+    }
+
+   so when inflate() is called again, the same case is attempted again, and
+   if the appropriate resources are provided, the machine proceeds to the
+   next state.  The NEEDBITS() macro is usually the way the state evaluates
+   whether it can proceed or should return.  NEEDBITS() does the return if
+   the requested bits are not available.  The typical use of the BITS macros
+   is:
+
+        NEEDBITS(n);
+        ... do something with BITS(n) ...
+        DROPBITS(n);
+
+   where NEEDBITS(n) either returns from inflate() if there isn't enough
+   input left to load n bits into the accumulator, or it continues.  BITS(n)
+   gives the low n bits in the accumulator.  When done, DROPBITS(n) drops
+   the low n bits off the accumulator.  INITBITS() clears the accumulator
+   and sets the number of available bits to zero.  BYTEBITS() discards just
+   enough bits to put the accumulator on a byte boundary.  After BYTEBITS()
+   and a NEEDBITS(8), then BITS(8) would return the next byte in the stream.
+
+   NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return
+   if there is no input available.  The decoding of variable length codes uses
+   PULLBYTE() directly in order to pull just enough bytes to decode the next
+   code, and no more.
+
+   Some states loop until they get enough input, making sure that enough
+   state information is maintained to continue the loop where it left off
+   if NEEDBITS() returns in the loop.  For example, want, need, and keep
+   would all have to actually be part of the saved state in case NEEDBITS()
+   returns:
+
+    case STATEw:
+        while (want < need) {
+            NEEDBITS(n);
+            keep[want++] = BITS(n);
+            DROPBITS(n);
+        }
+        state = STATEx;
+    case STATEx:
+
+   As shown above, if the next state is also the next case, then the break
+   is omitted.
+
+   A state may also return if there is not enough output space available to
+   complete that state.  Those states are copying stored data, writing a
+   literal byte, and copying a matching string.
+
+   When returning, a "goto inf_leave" is used to update the total counters,
+   update the check value, and determine whether any progress has been made
+   during that inflate() call in order to return the proper return code.
+   Progress is defined as a change in either strm->avail_in or strm->avail_out.
+   When there is a window, goto inf_leave will update the window with the last
+   output written.  If a goto inf_leave occurs in the middle of decompression
+   and there is no window currently, goto inf_leave will create one and copy
+   output to the window for the next call of inflate().
+
+   In this implementation, the flush parameter of inflate() only affects the
+   return code (per zlib.h).  inflate() always writes as much as possible to
+   strm->next_out, given the space available and the provided input--the effect
+   documented in zlib.h of Z_SYNC_FLUSH.  Furthermore, inflate() always defers
+   the allocation of and copying into a sliding window until necessary, which
+   provides the effect documented in zlib.h for Z_FINISH when the entire input
+   stream available.  So the only thing the flush parameter actually does is:
+   when flush is set to Z_FINISH, inflate() cannot return Z_OK.  Instead it
+   will return Z_BUF_ERROR if it has not reached the end of the stream.
+ */
+
+int ZEXPORT inflate(strm, flush)
+z_streamp strm;
+int flush;
+{
+    struct inflate_state FAR *state;
+    unsigned char FAR *next;    /* next input */
+    unsigned char FAR *put;     /* next output */
+    unsigned have, left;        /* available input and output */
+    unsigned long hold;         /* bit buffer */
+    unsigned bits;              /* bits in bit buffer */
+    unsigned in, out;           /* save starting available input and output */
+    unsigned copy;              /* number of stored or match bytes to copy */
+    unsigned char FAR *from;    /* where to copy match bytes from */
+    code this;                  /* current decoding table entry */
+    code last;                  /* parent table entry */
+    unsigned len;               /* length to copy for repeats, bits to drop */
+    int ret;                    /* return code */
+#ifdef GUNZIP
+    unsigned char hbuf[4];      /* buffer for gzip header crc calculation */
+#endif
+    static const unsigned short order[19] = /* permutation of code lengths */
+        {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
+
+    if (strm == Z_NULL || strm->state == Z_NULL || strm->next_out == Z_NULL ||
+        (strm->next_in == Z_NULL && strm->avail_in != 0))
+        return Z_STREAM_ERROR;
+
+    state = (struct inflate_state FAR *)strm->state;
+    if (state->mode == TYPE) state->mode = TYPEDO;      /* skip check */
+    LOAD();
+    in = have;
+    out = left;
+    ret = Z_OK;
+    for (;;)
+        switch (state->mode) {
+        case HEAD:
+            if (state->wrap == 0) {
+                state->mode = TYPEDO;
+                break;
+            }
+            NEEDBITS(16);
+#ifdef GUNZIP
+            if ((state->wrap & 2) && hold == 0x8b1f) {  /* gzip header */
+                state->check = crc32(0L, Z_NULL, 0);
+                CRC2(state->check, hold);
+                INITBITS();
+                state->mode = FLAGS;
+                break;
+            }
+            state->flags = 0;           /* expect zlib header */
+            if (state->head != Z_NULL)
+                state->head->done = -1;
+            if (!(state->wrap & 1) ||   /* check if zlib header allowed */
+#else
+            if (
+#endif
+                ((BITS(8) << 8) + (hold >> 8)) % 31) {
+                strm->msg = (char *)"incorrect header check";
+                state->mode = BAD;
+                break;
+            }
+            if (BITS(4) != Z_DEFLATED) {
+                strm->msg = (char *)"unknown compression method";
+                state->mode = BAD;
+                break;
+            }
+            DROPBITS(4);
+            len = BITS(4) + 8;
+            if (len > state->wbits) {
+                strm->msg = (char *)"invalid window size";
+                state->mode = BAD;
+                break;
+            }
+            state->dmax = 1U << len;
+            Tracev((stderr, "inflate:   zlib header ok\n"));
+            strm->adler = state->check = adler32(0L, Z_NULL, 0);
+            state->mode = hold & 0x200 ? DICTID : TYPE;
+            INITBITS();
+            break;
+#ifdef GUNZIP
+        case FLAGS:
+            NEEDBITS(16);
+            state->flags = (int)(hold);
+            if ((state->flags & 0xff) != Z_DEFLATED) {
+                strm->msg = (char *)"unknown compression method";
+                state->mode = BAD;
+                break;
+            }
+            if (state->flags & 0xe000) {
+                strm->msg = (char *)"unknown header flags set";
+                state->mode = BAD;
+                break;
+            }
+            if (state->head != Z_NULL)
+                state->head->text = (int)((hold >> 8) & 1);
+            if (state->flags & 0x0200) CRC2(state->check, hold);
+            INITBITS();
+            state->mode = TIME;
+        case TIME:
+            NEEDBITS(32);
+            if (state->head != Z_NULL)
+                state->head->time = hold;
+            if (state->flags & 0x0200) CRC4(state->check, hold);
+            INITBITS();
+            state->mode = OS;
+        case OS:
+            NEEDBITS(16);
+            if (state->head != Z_NULL) {
+                state->head->xflags = (int)(hold & 0xff);
+                state->head->os = (int)(hold >> 8);
+            }
+            if (state->flags & 0x0200) CRC2(state->check, hold);
+            INITBITS();
+            state->mode = EXLEN;
+        case EXLEN:
+            if (state->flags & 0x0400) {
+                NEEDBITS(16);
+                state->length = (unsigned)(hold);
+                if (state->head != Z_NULL)
+                    state->head->extra_len = (unsigned)hold;
+                if (state->flags & 0x0200) CRC2(state->check, hold);
+                INITBITS();
+            }
+            else if (state->head != Z_NULL)
+                state->head->extra = Z_NULL;
+            state->mode = EXTRA;
+        case EXTRA:
+            if (state->flags & 0x0400) {
+                copy = state->length;
+                if (copy > have) copy = have;
+                if (copy) {
+                    if (state->head != Z_NULL &&
+                        state->head->extra != Z_NULL) {
+                        len = state->head->extra_len - state->length;
+                        zmemcpy(state->head->extra + len, next,
+                                len + copy > state->head->extra_max ?
+                                state->head->extra_max - len : copy);
+                    }
+                    if (state->flags & 0x0200)
+                        state->check = crc32(state->check, next, copy);
+                    have -= copy;
+                    next += copy;
+                    state->length -= copy;
+                }
+                if (state->length) goto inf_leave;
+            }
+            state->length = 0;
+            state->mode = NAME;
+        case NAME:
+            if (state->flags & 0x0800) {
+                if (have == 0) goto inf_leave;
+                copy = 0;
+                do {
+                    len = (unsigned)(next[copy++]);
+                    if (state->head != Z_NULL &&
+                            state->head->name != Z_NULL &&
+                            state->length < state->head->name_max)
+                        state->head->name[state->length++] = len;
+                } while (len && copy < have);
+                if (state->flags & 0x0200)
+                    state->check = crc32(state->check, next, copy);
+                have -= copy;
+                next += copy;
+                if (len) goto inf_leave;
+            }
+            else if (state->head != Z_NULL)
+                state->head->name = Z_NULL;
+            state->length = 0;
+            state->mode = COMMENT;
+        case COMMENT:
+            if (state->flags & 0x1000) {
+                if (have == 0) goto inf_leave;
+                copy = 0;
+                do {
+                    len = (unsigned)(next[copy++]);
+                    if (state->head != Z_NULL &&
+                            state->head->comment != Z_NULL &&
+                            state->length < state->head->comm_max)
+                        state->head->comment[state->length++] = len;
+                } while (len && copy < have);
+                if (state->flags & 0x0200)
+                    state->check = crc32(state->check, next, copy);
+                have -= copy;
+                next += copy;
+                if (len) goto inf_leave;
+            }
+            else if (state->head != Z_NULL)
+                state->head->comment = Z_NULL;
+            state->mode = HCRC;
+        case HCRC:
+            if (state->flags & 0x0200) {
+                NEEDBITS(16);
+                if (hold != (state->check & 0xffff)) {
+                    strm->msg = (char *)"header crc mismatch";
+                    state->mode = BAD;
+                    break;
+                }
+                INITBITS();
+            }
+            if (state->head != Z_NULL) {
+                state->head->hcrc = (int)((state->flags >> 9) & 1);
+                state->head->done = 1;
+            }
+            strm->adler = state->check = crc32(0L, Z_NULL, 0);
+            state->mode = TYPE;
+            break;
+#endif
+        case DICTID:
+            NEEDBITS(32);
+            strm->adler = state->check = REVERSE(hold);
+            INITBITS();
+            state->mode = DICT;
+        case DICT:
+            if (state->havedict == 0) {
+                RESTORE();
+                return Z_NEED_DICT;
+            }
+            strm->adler = state->check = adler32(0L, Z_NULL, 0);
+            state->mode = TYPE;
+        case TYPE:
+            if (flush == Z_BLOCK) goto inf_leave;
+        case TYPEDO:
+            if (state->last) {
+                BYTEBITS();
+                state->mode = CHECK;
+                break;
+            }
+            NEEDBITS(3);
+            state->last = BITS(1);
+            DROPBITS(1);
+            switch (BITS(2)) {
+            case 0:                             /* stored block */
+                Tracev((stderr, "inflate:     stored block%s\n",
+                        state->last ? " (last)" : ""));
+                state->mode = STORED;
+                break;
+            case 1:                             /* fixed block */
+                fixedtables(state);
+                Tracev((stderr, "inflate:     fixed codes block%s\n",
+                        state->last ? " (last)" : ""));
+                state->mode = LEN;              /* decode codes */
+                break;
+            case 2:                             /* dynamic block */
+                Tracev((stderr, "inflate:     dynamic codes block%s\n",
+                        state->last ? " (last)" : ""));
+                state->mode = TABLE;
+                break;
+            case 3:
+                strm->msg = (char *)"invalid block type";
+                state->mode = BAD;
+            }
+            DROPBITS(2);
+            break;
+        case STORED:
+            BYTEBITS();                         /* go to byte boundary */
+            NEEDBITS(32);
+            if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
+                strm->msg = (char *)"invalid stored block lengths";
+                state->mode = BAD;
+                break;
+            }
+            state->length = (unsigned)hold & 0xffff;
+            Tracev((stderr, "inflate:       stored length %u\n",
+                    state->length));
+            INITBITS();
+            state->mode = COPY;
+        case COPY:
+            copy = state->length;
+            if (copy) {
+                if (copy > have) copy = have;
+                if (copy > left) copy = left;
+                if (copy == 0) goto inf_leave;
+                zmemcpy(put, next, copy);
+                have -= copy;
+                next += copy;
+                left -= copy;
+                put += copy;
+                state->length -= copy;
+                break;
+            }
+            Tracev((stderr, "inflate:       stored end\n"));
+            state->mode = TYPE;
+            break;
+        case TABLE:
+            NEEDBITS(14);
+            state->nlen = BITS(5) + 257;
+            DROPBITS(5);
+            state->ndist = BITS(5) + 1;
+            DROPBITS(5);
+            state->ncode = BITS(4) + 4;
+            DROPBITS(4);
+#ifndef PKZIP_BUG_WORKAROUND
+            if (state->nlen > 286 || state->ndist > 30) {
+                strm->msg = (char *)"too many length or distance symbols";
+                state->mode = BAD;
+                break;
+            }
+#endif
+            Tracev((stderr, "inflate:       table sizes ok\n"));
+            state->have = 0;
+            state->mode = LENLENS;
+        case LENLENS:
+            while (state->have < state->ncode) {
+                NEEDBITS(3);
+                state->lens[order[state->have++]] = (unsigned short)BITS(3);
+                DROPBITS(3);
+            }
+            while (state->have < 19)
+                state->lens[order[state->have++]] = 0;
+            state->next = state->codes;
+            state->lencode = (code const FAR *)(state->next);
+            state->lenbits = 7;
+            ret = inflate_table(CODES, state->lens, 19, &(state->next),
+                                &(state->lenbits), state->work);
+            if (ret) {
+                strm->msg = (char *)"invalid code lengths set";
+                state->mode = BAD;
+                break;
+            }
+            Tracev((stderr, "inflate:       code lengths ok\n"));
+            state->have = 0;
+            state->mode = CODELENS;
+        case CODELENS:
+            while (state->have < state->nlen + state->ndist) {
+                for (;;) {
+                    this = state->lencode[BITS(state->lenbits)];
+                    if ((unsigned)(this.bits) <= bits) break;
+                    PULLBYTE();
+                }
+                if (this.val < 16) {
+                    NEEDBITS(this.bits);
+                    DROPBITS(this.bits);
+                    state->lens[state->have++] = this.val;
+                }
+                else {
+                    if (this.val == 16) {
+                        NEEDBITS(this.bits + 2);
+                        DROPBITS(this.bits);
+                        if (state->have == 0) {
+                            strm->msg = (char *)"invalid bit length repeat";
+                            state->mode = BAD;
+                            break;
+                        }
+                        len = state->lens[state->have - 1];
+                        copy = 3 + BITS(2);
+                        DROPBITS(2);
+                    }
+                    else if (this.val == 17) {
+                        NEEDBITS(this.bits + 3);
+                        DROPBITS(this.bits);
+                        len = 0;
+                        copy = 3 + BITS(3);
+                        DROPBITS(3);
+                    }
+                    else {
+                        NEEDBITS(this.bits + 7);
+                        DROPBITS(this.bits);
+                        len = 0;
+                        copy = 11 + BITS(7);
+                        DROPBITS(7);
+                    }
+                    if (state->have + copy > state->nlen + state->ndist) {
+                        strm->msg = (char *)"invalid bit length repeat";
+                        state->mode = BAD;
+                        break;
+                    }
+                    while (copy--)
+                        state->lens[state->have++] = (unsigned short)len;
+                }
+            }
+
+            /* handle error breaks in while */
+            if (state->mode == BAD) break;
+
+            /* build code tables */
+            state->next = state->codes;
+            state->lencode = (code const FAR *)(state->next);
+            state->lenbits = 9;
+            ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
+                                &(state->lenbits), state->work);
+            if (ret) {
+                strm->msg = (char *)"invalid literal/lengths set";
+                state->mode = BAD;
+                break;
+            }
+            state->distcode = (code const FAR *)(state->next);
+            state->distbits = 6;
+            ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist,
+                            &(state->next), &(state->distbits), state->work);
+            if (ret) {
+                strm->msg = (char *)"invalid distances set";
+                state->mode = BAD;
+                break;
+            }
+            Tracev((stderr, "inflate:       codes ok\n"));
+            state->mode = LEN;
+        case LEN:
+            if (have >= 6 && left >= 258) {
+                RESTORE();
+                inflate_fast(strm, out);
+                LOAD();
+                break;
+            }
+            for (;;) {
+                this = state->lencode[BITS(state->lenbits)];
+                if ((unsigned)(this.bits) <= bits) break;
+                PULLBYTE();
+            }
+            if (this.op && (this.op & 0xf0) == 0) {
+                last = this;
+                for (;;) {
+                    this = state->lencode[last.val +
+                            (BITS(last.bits + last.op) >> last.bits)];
+                    if ((unsigned)(last.bits + this.bits) <= bits) break;
+                    PULLBYTE();
+                }
+                DROPBITS(last.bits);
+            }
+            DROPBITS(this.bits);
+            state->length = (unsigned)this.val;
+            if ((int)(this.op) == 0) {
+                Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ?
+                        "inflate:         literal '%c'\n" :
+                        "inflate:         literal 0x%02x\n", this.val));
+                state->mode = LIT;
+                break;
+            }
+            if (this.op & 32) {
+                Tracevv((stderr, "inflate:         end of block\n"));
+                state->mode = TYPE;
+                break;
+            }
+            if (this.op & 64) {
+                strm->msg = (char *)"invalid literal/length code";
+                state->mode = BAD;
+                break;
+            }
+            state->extra = (unsigned)(this.op) & 15;
+            state->mode = LENEXT;
+        case LENEXT:
+            if (state->extra) {
+                NEEDBITS(state->extra);
+                state->length += BITS(state->extra);
+                DROPBITS(state->extra);
+            }
+            Tracevv((stderr, "inflate:         length %u\n", state->length));
+            state->mode = DIST;
+        case DIST:
+            for (;;) {
+                this = state->distcode[BITS(state->distbits)];
+                if ((unsigned)(this.bits) <= bits) break;
+                PULLBYTE();
+            }
+            if ((this.op & 0xf0) == 0) {
+                last = this;
+                for (;;) {
+                    this = state->distcode[last.val +
+                            (BITS(last.bits + last.op) >> last.bits)];
+                    if ((unsigned)(last.bits + this.bits) <= bits) break;
+                    PULLBYTE();
+                }
+                DROPBITS(last.bits);
+            }
+            DROPBITS(this.bits);
+            if (this.op & 64) {
+                strm->msg = (char *)"invalid distance code";
+                state->mode = BAD;
+                break;
+            }
+            state->offset = (unsigned)this.val;
+            state->extra = (unsigned)(this.op) & 15;
+            state->mode = DISTEXT;
+        case DISTEXT:
+            if (state->extra) {
+                NEEDBITS(state->extra);
+                state->offset += BITS(state->extra);
+                DROPBITS(state->extra);
+            }
+#ifdef INFLATE_STRICT
+            if (state->offset > state->dmax) {
+                strm->msg = (char *)"invalid distance too far back";
+                state->mode = BAD;
+                break;
+            }
+#endif
+            if (state->offset > state->whave + out - left) {
+                strm->msg = (char *)"invalid distance too far back";
+                state->mode = BAD;
+                break;
+            }
+            Tracevv((stderr, "inflate:         distance %u\n", state->offset));
+            state->mode = MATCH;
+        case MATCH:
+            if (left == 0) goto inf_leave;
+            copy = out - left;
+            if (state->offset > copy) {         /* copy from window */
+                copy = state->offset - copy;
+                if (copy > state->write) {
+                    copy -= state->write;
+                    from = state->window + (state->wsize - copy);
+                }
+                else
+                    from = state->window + (state->write - copy);
+                if (copy > state->length) copy = state->length;
+            }
+            else {                              /* copy from output */
+                from = put - state->offset;
+                copy = state->length;
+            }
+            if (copy > left) copy = left;
+            left -= copy;
+            state->length -= copy;
+            do {
+                *put++ = *from++;
+            } while (--copy);
+            if (state->length == 0) state->mode = LEN;
+            break;
+        case LIT:
+            if (left == 0) goto inf_leave;
+            *put++ = (unsigned char)(state->length);
+            left--;
+            state->mode = LEN;
+            break;
+        case CHECK:
+            if (state->wrap) {
+                NEEDBITS(32);
+                out -= left;
+                strm->total_out += out;
+                state->total += out;
+                if (out)
+                    strm->adler = state->check =
+                        UPDATE(state->check, put - out, out);
+                out = left;
+                if ((
+#ifdef GUNZIP
+                     state->flags ? hold :
+#endif
+                     REVERSE(hold)) != state->check) {
+                    strm->msg = (char *)"incorrect data check";
+                    state->mode = BAD;
+                    break;
+                }
+                INITBITS();
+                Tracev((stderr, "inflate:   check matches trailer\n"));
+            }
+#ifdef GUNZIP
+            state->mode = LENGTH;
+        case LENGTH:
+            if (state->wrap && state->flags) {
+                NEEDBITS(32);
+                if (hold != (state->total & 0xffffffffUL)) {
+                    strm->msg = (char *)"incorrect length check";
+                    state->mode = BAD;
+                    break;
+                }
+                INITBITS();
+                Tracev((stderr, "inflate:   length matches trailer\n"));
+            }
+#endif
+            state->mode = DONE;
+        case DONE:
+            ret = Z_STREAM_END;
+            goto inf_leave;
+        case BAD:
+            ret = Z_DATA_ERROR;
+            goto inf_leave;
+        case MEM:
+            return Z_MEM_ERROR;
+        case SYNC:
+        default:
+            return Z_STREAM_ERROR;
+        }
+
+    /*
+       Return from inflate(), updating the total counts and the check value.
+       If there was no progress during the inflate() call, return a buffer
+       error.  Call updatewindow() to create and/or update the window state.
+       Note: a memory error from inflate() is non-recoverable.
+     */
+  inf_leave:
+    RESTORE();
+    if (state->wsize || (state->mode < CHECK && out != strm->avail_out))
+        if (updatewindow(strm, out)) {
+            state->mode = MEM;
+            return Z_MEM_ERROR;
+        }
+    in -= strm->avail_in;
+    out -= strm->avail_out;
+    strm->total_in += in;
+    strm->total_out += out;
+    state->total += out;
+    if (state->wrap && out)
+        strm->adler = state->check =
+            UPDATE(state->check, strm->next_out - out, out);
+    strm->data_type = state->bits + (state->last ? 64 : 0) +
+                      (state->mode == TYPE ? 128 : 0);
+    if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
+        ret = Z_BUF_ERROR;
+    return ret;
+}
+
+int ZEXPORT inflateEnd(strm)
+z_streamp strm;
+{
+    struct inflate_state FAR *state;
+    if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0)
+        return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)strm->state;
+    if (state->window != Z_NULL) ZFREE(strm, state->window);
+    ZFREE(strm, strm->state);
+    strm->state = Z_NULL;
+    Tracev((stderr, "inflate: end\n"));
+    return Z_OK;
+}
+
+int ZEXPORT inflateSetDictionary(strm, dictionary, dictLength)
+z_streamp strm;
+const Bytef *dictionary;
+uInt dictLength;
+{
+    struct inflate_state FAR *state;
+    unsigned long id;
+
+    /* check state */
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)strm->state;
+    if (state->wrap != 0 && state->mode != DICT)
+        return Z_STREAM_ERROR;
+
+    /* check for correct dictionary id */
+    if (state->mode == DICT) {
+        id = adler32(0L, Z_NULL, 0);
+        id = adler32(id, dictionary, dictLength);
+        if (id != state->check)
+            return Z_DATA_ERROR;
+    }
+
+    /* copy dictionary to window */
+    if (updatewindow(strm, strm->avail_out)) {
+        state->mode = MEM;
+        return Z_MEM_ERROR;
+    }
+    if (dictLength > state->wsize) {
+        zmemcpy(state->window, dictionary + dictLength - state->wsize,
+                state->wsize);
+        state->whave = state->wsize;
+    }
+    else {
+        zmemcpy(state->window + state->wsize - dictLength, dictionary,
+                dictLength);
+        state->whave = dictLength;
+    }
+    state->havedict = 1;
+    Tracev((stderr, "inflate:   dictionary set\n"));
+    return Z_OK;
+}
+
+int ZEXPORT inflateGetHeader(strm, head)
+z_streamp strm;
+gz_headerp head;
+{
+    struct inflate_state FAR *state;
+
+    /* check state */
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)strm->state;
+    if ((state->wrap & 2) == 0) return Z_STREAM_ERROR;
+
+    /* save header structure */
+    state->head = head;
+    head->done = 0;
+    return Z_OK;
+}
+
+/*
+   Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff.  Return when found
+   or when out of input.  When called, *have is the number of pattern bytes
+   found in order so far, in 0..3.  On return *have is updated to the new
+   state.  If on return *have equals four, then the pattern was found and the
+   return value is how many bytes were read including the last byte of the
+   pattern.  If *have is less than four, then the pattern has not been found
+   yet and the return value is len.  In the latter case, syncsearch() can be
+   called again with more data and the *have state.  *have is initialized to
+   zero for the first call.
+ */
+local unsigned syncsearch(have, buf, len)
+unsigned FAR *have;
+unsigned char FAR *buf;
+unsigned len;
+{
+    unsigned got;
+    unsigned next;
+
+    got = *have;
+    next = 0;
+    while (next < len && got < 4) {
+        if ((int)(buf[next]) == (got < 2 ? 0 : 0xff))
+            got++;
+        else if (buf[next])
+            got = 0;
+        else
+            got = 4 - got;
+        next++;
+    }
+    *have = got;
+    return next;
+}
+
+int ZEXPORT inflateSync(strm)
+z_streamp strm;
+{
+    unsigned len;               /* number of bytes to look at or looked at */
+    unsigned long in, out;      /* temporary to save total_in and total_out */
+    unsigned char buf[4];       /* to restore bit buffer to byte string */
+    struct inflate_state FAR *state;
+
+    /* check parameters */
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)strm->state;
+    if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR;
+
+    /* if first time, start search in bit buffer */
+    if (state->mode != SYNC) {
+        state->mode = SYNC;
+        state->hold <<= state->bits & 7;
+        state->bits -= state->bits & 7;
+        len = 0;
+        while (state->bits >= 8) {
+            buf[len++] = (unsigned char)(state->hold);
+            state->hold >>= 8;
+            state->bits -= 8;
+        }
+        state->have = 0;
+        syncsearch(&(state->have), buf, len);
+    }
+
+    /* search available input */
+    len = syncsearch(&(state->have), strm->next_in, strm->avail_in);
+    strm->avail_in -= len;
+    strm->next_in += len;
+    strm->total_in += len;
+
+    /* return no joy or set up to restart inflate() on a new block */
+    if (state->have != 4) return Z_DATA_ERROR;
+    in = strm->total_in;  out = strm->total_out;
+    inflateReset(strm);
+    strm->total_in = in;  strm->total_out = out;
+    state->mode = TYPE;
+    return Z_OK;
+}
+
+/*
+   Returns true if inflate is currently at the end of a block generated by
+   Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
+   implementation to provide an additional safety check. PPP uses
+   Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored
+   block. When decompressing, PPP checks that at the end of input packet,
+   inflate is waiting for these length bytes.
+ */
+int ZEXPORT inflateSyncPoint(strm)
+z_streamp strm;
+{
+    struct inflate_state FAR *state;
+
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)strm->state;
+    return state->mode == STORED && state->bits == 0;
+}
+
+int ZEXPORT inflateCopy(dest, source)
+z_streamp dest;
+z_streamp source;
+{
+    struct inflate_state FAR *state;
+    struct inflate_state FAR *copy;
+    unsigned char FAR *window;
+    unsigned wsize;
+
+    /* check input */
+    if (dest == Z_NULL || source == Z_NULL || source->state == Z_NULL ||
+        source->zalloc == (alloc_func)0 || source->zfree == (free_func)0)
+        return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)source->state;
+
+    /* allocate space */
+    copy = (struct inflate_state FAR *)
+           ZALLOC(source, 1, sizeof(struct inflate_state));
+    if (copy == Z_NULL) return Z_MEM_ERROR;
+    window = Z_NULL;
+    if (state->window != Z_NULL) {
+        window = (unsigned char FAR *)
+                 ZALLOC(source, 1U << state->wbits, sizeof(unsigned char));
+        if (window == Z_NULL) {
+            ZFREE(source, copy);
+            return Z_MEM_ERROR;
+        }
+    }
+
+    /* copy state */
+    zmemcpy(dest, source, sizeof(z_stream));
+    zmemcpy(copy, state, sizeof(struct inflate_state));
+    if (state->lencode >= state->codes &&
+        state->lencode <= state->codes + ENOUGH - 1) {
+        copy->lencode = copy->codes + (state->lencode - state->codes);
+        copy->distcode = copy->codes + (state->distcode - state->codes);
+    }
+    copy->next = copy->codes + (state->next - state->codes);
+    if (window != Z_NULL) {
+        wsize = 1U << state->wbits;
+        zmemcpy(window, state->window, wsize);
+    }
+    copy->window = window;
+    dest->state = (struct internal_state FAR *)copy;
+    return Z_OK;
+}
diff --git a/gs/zlib/inflate.h b/gs/zlib/inflate.h
new file mode 100644
index 000000000..07bd3e78a
--- /dev/null
+++ b/gs/zlib/inflate.h
@@ -0,0 +1,115 @@
+/* inflate.h -- internal inflate state definition
+ * Copyright (C) 1995-2004 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* WARNING: this file should *not* be used by applications. It is
+   part of the implementation of the compression library and is
+   subject to change. Applications should only use zlib.h.
+ */
+
+/* define NO_GZIP when compiling if you want to disable gzip header and
+   trailer decoding by inflate().  NO_GZIP would be used to avoid linking in
+   the crc code when it is not needed.  For shared libraries, gzip decoding
+   should be left enabled. */
+#ifndef NO_GZIP
+#  define GUNZIP
+#endif
+
+/* Possible inflate modes between inflate() calls */
+typedef enum {
+    HEAD,       /* i: waiting for magic header */
+    FLAGS,      /* i: waiting for method and flags (gzip) */
+    TIME,       /* i: waiting for modification time (gzip) */
+    OS,         /* i: waiting for extra flags and operating system (gzip) */
+    EXLEN,      /* i: waiting for extra length (gzip) */
+    EXTRA,      /* i: waiting for extra bytes (gzip) */
+    NAME,       /* i: waiting for end of file name (gzip) */
+    COMMENT,    /* i: waiting for end of comment (gzip) */
+    HCRC,       /* i: waiting for header crc (gzip) */
+    DICTID,     /* i: waiting for dictionary check value */
+    DICT,       /* waiting for inflateSetDictionary() call */
+        TYPE,       /* i: waiting for type bits, including last-flag bit */
+        TYPEDO,     /* i: same, but skip check to exit inflate on new block */
+        STORED,     /* i: waiting for stored size (length and complement) */
+        COPY,       /* i/o: waiting for input or output to copy stored block */
+        TABLE,      /* i: waiting for dynamic block table lengths */
+        LENLENS,    /* i: waiting for code length code lengths */
+        CODELENS,   /* i: waiting for length/lit and distance code lengths */
+            LEN,        /* i: waiting for length/lit code */
+            LENEXT,     /* i: waiting for length extra bits */
+            DIST,       /* i: waiting for distance code */
+            DISTEXT,    /* i: waiting for distance extra bits */
+            MATCH,      /* o: waiting for output space to copy string */
+            LIT,        /* o: waiting for output space to write literal */
+    CHECK,      /* i: waiting for 32-bit check value */
+    LENGTH,     /* i: waiting for 32-bit length (gzip) */
+    DONE,       /* finished check, done -- remain here until reset */
+    BAD,        /* got a data error -- remain here until reset */
+    MEM,        /* got an inflate() memory error -- remain here until reset */
+    SYNC        /* looking for synchronization bytes to restart inflate() */
+} inflate_mode;
+
+/*
+    State transitions between above modes -
+
+    (most modes can go to the BAD or MEM mode -- not shown for clarity)
+
+    Process header:
+        HEAD -> (gzip) or (zlib)
+        (gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME
+        NAME -> COMMENT -> HCRC -> TYPE
+        (zlib) -> DICTID or TYPE
+        DICTID -> DICT -> TYPE
+    Read deflate blocks:
+            TYPE -> STORED or TABLE or LEN or CHECK
+            STORED -> COPY -> TYPE
+            TABLE -> LENLENS -> CODELENS -> LEN
+    Read deflate codes:
+                LEN -> LENEXT or LIT or TYPE
+                LENEXT -> DIST -> DISTEXT -> MATCH -> LEN
+                LIT -> LEN
+    Process trailer:
+        CHECK -> LENGTH -> DONE
+ */
+
+/* state maintained between inflate() calls.  Approximately 7K bytes. */
+struct inflate_state {
+    inflate_mode mode;          /* current inflate mode */
+    int last;                   /* true if processing last block */
+    int wrap;                   /* bit 0 true for zlib, bit 1 true for gzip */
+    int havedict;               /* true if dictionary provided */
+    int flags;                  /* gzip header method and flags (0 if zlib) */
+    unsigned dmax;              /* zlib header max distance (INFLATE_STRICT) */
+    unsigned long check;        /* protected copy of check value */
+    unsigned long total;        /* protected copy of output count */
+    gz_headerp head;            /* where to save gzip header information */
+        /* sliding window */
+    unsigned wbits;             /* log base 2 of requested window size */
+    unsigned wsize;             /* window size or zero if not using window */
+    unsigned whave;             /* valid bytes in the window */
+    unsigned write;             /* window write index */
+    unsigned char FAR *window;  /* allocated sliding window, if needed */
+        /* bit accumulator */
+    unsigned long hold;         /* input bit accumulator */
+    unsigned bits;              /* number of bits in "in" */
+        /* for string and stored block copying */
+    unsigned length;            /* literal or length of data to copy */
+    unsigned offset;            /* distance back to copy string from */
+        /* for table and code decoding */
+    unsigned extra;             /* extra bits needed */
+        /* fixed and dynamic code tables */
+    code const FAR *lencode;    /* starting table for length/literal codes */
+    code const FAR *distcode;   /* starting table for distance codes */
+    unsigned lenbits;           /* index bits for lencode */
+    unsigned distbits;          /* index bits for distcode */
+        /* dynamic table building */
+    unsigned ncode;             /* number of code length code lengths */
+    unsigned nlen;              /* number of length code lengths */
+    unsigned ndist;             /* number of distance code lengths */
+    unsigned have;              /* number of code lengths in lens[] */
+    code FAR *next;             /* next available space in codes[] */
+    unsigned short lens[320];   /* temporary storage for code lengths */
+    unsigned short work[288];   /* work area for code table building */
+    code codes[ENOUGH];         /* space for code tables */
+};
diff --git a/gs/zlib/inftrees.c b/gs/zlib/inftrees.c
new file mode 100644
index 000000000..8a9c13ff0
--- /dev/null
+++ b/gs/zlib/inftrees.c
@@ -0,0 +1,329 @@
+/* inftrees.c -- generate Huffman trees for efficient decoding
+ * Copyright (C) 1995-2005 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#include "zutil.h"
+#include "inftrees.h"
+
+#define MAXBITS 15
+
+const char inflate_copyright[] =
+   " inflate 1.2.3 Copyright 1995-2005 Mark Adler ";
+/*
+  If you use the zlib library in a product, an acknowledgment is welcome
+  in the documentation of your product. If for some reason you cannot
+  include such an acknowledgment, I would appreciate that you keep this
+  copyright string in the executable of your product.
+ */
+
+/*
+   Build a set of tables to decode the provided canonical Huffman code.
+   The code lengths are lens[0..codes-1].  The result starts at *table,
+   whose indices are 0..2^bits-1.  work is a writable array of at least
+   lens shorts, which is used as a work area.  type is the type of code
+   to be generated, CODES, LENS, or DISTS.  On return, zero is success,
+   -1 is an invalid code, and +1 means that ENOUGH isn't enough.  table
+   on return points to the next available entry's address.  bits is the
+   requested root table index bits, and on return it is the actual root
+   table index bits.  It will differ if the request is greater than the
+   longest code or if it is less than the shortest code.
+ */
+int inflate_table(type, lens, codes, table, bits, work)
+codetype type;
+unsigned short FAR *lens;
+unsigned codes;
+code FAR * FAR *table;
+unsigned FAR *bits;
+unsigned short FAR *work;
+{
+    unsigned len;               /* a code's length in bits */
+    unsigned sym;               /* index of code symbols */
+    unsigned min, max;          /* minimum and maximum code lengths */
+    unsigned root;              /* number of index bits for root table */
+    unsigned curr;              /* number of index bits for current table */
+    unsigned drop;              /* code bits to drop for sub-table */
+    int left;                   /* number of prefix codes available */
+    unsigned used;              /* code entries in table used */
+    unsigned huff;              /* Huffman code */
+    unsigned incr;              /* for incrementing code, index */
+    unsigned fill;              /* index for replicating entries */
+    unsigned low;               /* low bits for current root entry */
+    unsigned mask;              /* mask for low root bits */
+    code this;                  /* table entry for duplication */
+    code FAR *next;             /* next available space in table */
+    const unsigned short FAR *base;     /* base value table to use */
+    const unsigned short FAR *extra;    /* extra bits table to use */
+    int end;                    /* use base and extra for symbol > end */
+    unsigned short count[MAXBITS+1];    /* number of codes of each length */
+    unsigned short offs[MAXBITS+1];     /* offsets in table for each length */
+    static const unsigned short lbase[31] = { /* Length codes 257..285 base */
+        3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
+        35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
+    static const unsigned short lext[31] = { /* Length codes 257..285 extra */
+        16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18,
+        19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 201, 196};
+    static const unsigned short dbase[32] = { /* Distance codes 0..29 base */
+        1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
+        257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
+        8193, 12289, 16385, 24577, 0, 0};
+    static const unsigned short dext[32] = { /* Distance codes 0..29 extra */
+        16, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22,
+        23, 23, 24, 24, 25, 25, 26, 26, 27, 27,
+        28, 28, 29, 29, 64, 64};
+
+    /*
+       Process a set of code lengths to create a canonical Huffman code.  The
+       code lengths are lens[0..codes-1].  Each length corresponds to the
+       symbols 0..codes-1.  The Huffman code is generated by first sorting the
+       symbols by length from short to long, and retaining the symbol order
+       for codes with equal lengths.  Then the code starts with all zero bits
+       for the first code of the shortest length, and the codes are integer
+       increments for the same length, and zeros are appended as the length
+       increases.  For the deflate format, these bits are stored backwards
+       from their more natural integer increment ordering, and so when the
+       decoding tables are built in the large loop below, the integer codes
+       are incremented backwards.
+
+       This routine assumes, but does not check, that all of the entries in
+       lens[] are in the range 0..MAXBITS.  The caller must assure this.
+       1..MAXBITS is interpreted as that code length.  zero means that that
+       symbol does not occur in this code.
+
+       The codes are sorted by computing a count of codes for each length,
+       creating from that a table of starting indices for each length in the
+       sorted table, and then entering the symbols in order in the sorted
+       table.  The sorted table is work[], with that space being provided by
+       the caller.
+
+       The length counts are used for other purposes as well, i.e. finding
+       the minimum and maximum length codes, determining if there are any
+       codes at all, checking for a valid set of lengths, and looking ahead
+       at length counts to determine sub-table sizes when building the
+       decoding tables.
+     */
+
+    /* accumulate lengths for codes (assumes lens[] all in 0..MAXBITS) */
+    for (len = 0; len <= MAXBITS; len++)
+        count[len] = 0;
+    for (sym = 0; sym < codes; sym++)
+        count[lens[sym]]++;
+
+    /* bound code lengths, force root to be within code lengths */
+    root = *bits;
+    for (max = MAXBITS; max >= 1; max--)
+        if (count[max] != 0) break;
+    if (root > max) root = max;
+    if (max == 0) {                     /* no symbols to code at all */
+        this.op = (unsigned char)64;    /* invalid code marker */
+        this.bits = (unsigned char)1;
+        this.val = (unsigned short)0;
+        *(*table)++ = this;             /* make a table to force an error */
+        *(*table)++ = this;
+        *bits = 1;
+        return 0;     /* no symbols, but wait for decoding to report error */
+    }
+    for (min = 1; min <= MAXBITS; min++)
+        if (count[min] != 0) break;
+    if (root < min) root = min;
+
+    /* check for an over-subscribed or incomplete set of lengths */
+    left = 1;
+    for (len = 1; len <= MAXBITS; len++) {
+        left <<= 1;
+        left -= count[len];
+        if (left < 0) return -1;        /* over-subscribed */
+    }
+    if (left > 0 && (type == CODES || max != 1))
+        return -1;                      /* incomplete set */
+
+    /* generate offsets into symbol table for each length for sorting */
+    offs[1] = 0;
+    for (len = 1; len < MAXBITS; len++)
+        offs[len + 1] = offs[len] + count[len];
+
+    /* sort symbols by length, by symbol order within each length */
+    for (sym = 0; sym < codes; sym++)
+        if (lens[sym] != 0) work[offs[lens[sym]]++] = (unsigned short)sym;
+
+    /*
+       Create and fill in decoding tables.  In this loop, the table being
+       filled is at next and has curr index bits.  The code being used is huff
+       with length len.  That code is converted to an index by dropping drop
+       bits off of the bottom.  For codes where len is less than drop + curr,
+       those top drop + curr - len bits are incremented through all values to
+       fill the table with replicated entries.
+
+       root is the number of index bits for the root table.  When len exceeds
+       root, sub-tables are created pointed to by the root entry with an index
+       of the low root bits of huff.  This is saved in low to check for when a
+       new sub-table should be started.  drop is zero when the root table is
+       being filled, and drop is root when sub-tables are being filled.
+
+       When a new sub-table is needed, it is necessary to look ahead in the
+       code lengths to determine what size sub-table is needed.  The length
+       counts are used for this, and so count[] is decremented as codes are
+       entered in the tables.
+
+       used keeps track of how many table entries have been allocated from the
+       provided *table space.  It is checked when a LENS table is being made
+       against the space in *table, ENOUGH, minus the maximum space needed by
+       the worst case distance code, MAXD.  This should never happen, but the
+       sufficiency of ENOUGH has not been proven exhaustively, hence the check.
+       This assumes that when type == LENS, bits == 9.
+
+       sym increments through all symbols, and the loop terminates when
+       all codes of length max, i.e. all codes, have been processed.  This
+       routine permits incomplete codes, so another loop after this one fills
+       in the rest of the decoding tables with invalid code markers.
+     */
+
+    /* set up for code type */
+    switch (type) {
+    case CODES:
+        base = extra = work;    /* dummy value--not used */
+        end = 19;
+        break;
+    case LENS:
+        base = lbase;
+        base -= 257;
+        extra = lext;
+        extra -= 257;
+        end = 256;
+        break;
+    default:            /* DISTS */
+        base = dbase;
+        extra = dext;
+        end = -1;
+    }
+
+    /* initialize state for loop */
+    huff = 0;                   /* starting code */
+    sym = 0;                    /* starting code symbol */
+    len = min;                  /* starting code length */
+    next = *table;              /* current table to fill in */
+    curr = root;                /* current table index bits */
+    drop = 0;                   /* current bits to drop from code for index */
+    low = (unsigned)(-1);       /* trigger new sub-table when len > root */
+    used = 1U << root;          /* use root table entries */
+    mask = used - 1;            /* mask for comparing low */
+
+    /* check available table space */
+    if (type == LENS && used >= ENOUGH - MAXD)
+        return 1;
+
+    /* process all codes and make table entries */
+    for (;;) {
+        /* create table entry */
+        this.bits = (unsigned char)(len - drop);
+        if ((int)(work[sym]) < end) {
+            this.op = (unsigned char)0;
+            this.val = work[sym];
+        }
+        else if ((int)(work[sym]) > end) {
+            this.op = (unsigned char)(extra[work[sym]]);
+            this.val = base[work[sym]];
+        }
+        else {
+            this.op = (unsigned char)(32 + 64);         /* end of block */
+            this.val = 0;
+        }
+
+        /* replicate for those indices with low len bits equal to huff */
+        incr = 1U << (len - drop);
+        fill = 1U << curr;
+        min = fill;                 /* save offset to next table */
+        do {
+            fill -= incr;
+            next[(huff >> drop) + fill] = this;
+        } while (fill != 0);
+
+        /* backwards increment the len-bit code huff */
+        incr = 1U << (len - 1);
+        while (huff & incr)
+            incr >>= 1;
+        if (incr != 0) {
+            huff &= incr - 1;
+            huff += incr;
+        }
+        else
+            huff = 0;
+
+        /* go to next symbol, update count, len */
+        sym++;
+        if (--(count[len]) == 0) {
+            if (len == max) break;
+            len = lens[work[sym]];
+        }
+
+        /* create new sub-table if needed */
+        if (len > root && (huff & mask) != low) {
+            /* if first time, transition to sub-tables */
+            if (drop == 0)
+                drop = root;
+
+            /* increment past last table */
+            next += min;            /* here min is 1 << curr */
+
+            /* determine length of next table */
+            curr = len - drop;
+            left = (int)(1 << curr);
+            while (curr + drop < max) {
+                left -= count[curr + drop];
+                if (left <= 0) break;
+                curr++;
+                left <<= 1;
+            }
+
+            /* check for enough space */
+            used += 1U << curr;
+            if (type == LENS && used >= ENOUGH - MAXD)
+                return 1;
+
+            /* point entry in root table to sub-table */
+            low = huff & mask;
+            (*table)[low].op = (unsigned char)curr;
+            (*table)[low].bits = (unsigned char)root;
+            (*table)[low].val = (unsigned short)(next - *table);
+        }
+    }
+
+    /*
+       Fill in rest of table for incomplete codes.  This loop is similar to the
+       loop above in incrementing huff for table indices.  It is assumed that
+       len is equal to curr + drop, so there is no loop needed to increment
+       through high index bits.  When the current sub-table is filled, the loop
+       drops back to the root table to fill in any remaining entries there.
+     */
+    this.op = (unsigned char)64;                /* invalid code marker */
+    this.bits = (unsigned char)(len - drop);
+    this.val = (unsigned short)0;
+    while (huff != 0) {
+        /* when done with sub-table, drop back to root table */
+        if (drop != 0 && (huff & mask) != low) {
+            drop = 0;
+            len = root;
+            next = *table;
+            this.bits = (unsigned char)len;
+        }
+
+        /* put invalid code marker in table */
+        next[huff >> drop] = this;
+
+        /* backwards increment the len-bit code huff */
+        incr = 1U << (len - 1);
+        while (huff & incr)
+            incr >>= 1;
+        if (incr != 0) {
+            huff &= incr - 1;
+            huff += incr;
+        }
+        else
+            huff = 0;
+    }
+
+    /* set return parameters */
+    *table += used;
+    *bits = root;
+    return 0;
+}
diff --git a/gs/zlib/inftrees.h b/gs/zlib/inftrees.h
new file mode 100644
index 000000000..b1104c87e
--- /dev/null
+++ b/gs/zlib/inftrees.h
@@ -0,0 +1,55 @@
+/* inftrees.h -- header to use inftrees.c
+ * Copyright (C) 1995-2005 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* WARNING: this file should *not* be used by applications. It is
+   part of the implementation of the compression library and is
+   subject to change. Applications should only use zlib.h.
+ */
+
+/* Structure for decoding tables.  Each entry provides either the
+   information needed to do the operation requested by the code that
+   indexed that table entry, or it provides a pointer to another
+   table that indexes more bits of the code.  op indicates whether
+   the entry is a pointer to another table, a literal, a length or
+   distance, an end-of-block, or an invalid code.  For a table
+   pointer, the low four bits of op is the number of index bits of
+   that table.  For a length or distance, the low four bits of op
+   is the number of extra bits to get after the code.  bits is
+   the number of bits in this code or part of the code to drop off
+   of the bit buffer.  val is the actual byte to output in the case
+   of a literal, the base length or distance, or the offset from
+   the current table to the next table.  Each entry is four bytes. */
+typedef struct {
+    unsigned char op;           /* operation, extra bits, table bits */
+    unsigned char bits;         /* bits in this part of the code */
+    unsigned short val;         /* offset in table or code value */
+} code;
+
+/* op values as set by inflate_table():
+    00000000 - literal
+    0000tttt - table link, tttt != 0 is the number of table index bits
+    0001eeee - length or distance, eeee is the number of extra bits
+    01100000 - end of block
+    01000000 - invalid code
+ */
+
+/* Maximum size of dynamic tree.  The maximum found in a long but non-
+   exhaustive search was 1444 code structures (852 for length/literals
+   and 592 for distances, the latter actually the result of an
+   exhaustive search).  The true maximum is not known, but the value
+   below is more than safe. */
+#define ENOUGH 2048
+#define MAXD 592
+
+/* Type of code to build for inftable() */
+typedef enum {
+    CODES,
+    LENS,
+    DISTS
+} codetype;
+
+extern int inflate_table OF((codetype type, unsigned short FAR *lens,
+                             unsigned codes, code FAR * FAR *table,
+                             unsigned FAR *bits, unsigned short FAR *work));
diff --git a/gs/zlib/make_vms.com b/gs/zlib/make_vms.com
new file mode 100644
index 000000000..c2a1fb54b
--- /dev/null
+++ b/gs/zlib/make_vms.com
@@ -0,0 +1,461 @@
+$! make libz under VMS written by
+$! Martin P.J. Zinser
+$! <zinser@zinser.no-ip.info or zinser@sysdev.deutsche-boerse.com>
+$!
+$ on error then goto err_exit
+$!
+$!
+$! Just some general constants...
+$!
+$ true  = 1
+$ false = 0
+$ tmpnam = "temp_" + f$getjpi("","pid")
+$ SAY = "WRITE SYS$OUTPUT"
+$!
+$! Setup variables holding "config" information
+$!
+$ Make     = ""
+$ name     = "Zlib"
+$ version  = "?.?.?"
+$ v_string = "ZLIB_VERSION"
+$ v_file   = "zlib.h"
+$ ccopt    = ""
+$ lopts    = ""
+$ linkonly = false
+$ optfile  = name + ".opt"
+$ its_decc = false
+$ its_vaxc = false
+$ its_gnuc = false
+$ axp      = f$getsyi("HW_MODEL").ge.1024
+$ s_case   = false
+$! Check for MMK/MMS
+$!
+$ If F$Search ("Sys$System:MMS.EXE") .nes. "" Then Make = "MMS"
+$ If F$Type (MMK) .eqs. "STRING" Then Make = "MMK"
+$!
+$!
+$ gosub find_version
+$!
+$ gosub check_opts
+$!
+$! Look for the compiler used
+$!
+$ gosub check_compiler
+$ if its_decc
+$ then
+$   ccopt = "/prefix=all" + ccopt
+$   if f$trnlnm("SYS") .eqs. ""
+$   then
+$     if axp
+$     then
+$       define sys sys$library:
+$     else
+$       ccopt = "/decc" + ccopt
+$       define sys decc$library_include:
+$     endif
+$   endif
+$ endif
+$ if its_vaxc .or. its_gnuc
+$ then
+$    if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$ endif
+$!
+$! Build the thing plain or with mms
+$!
+$ write sys$output "Compiling Zlib sources ..."
+$ if make.eqs.""
+$  then
+$   dele example.obj;*,minigzip.obj;*
+$   CALL MAKE adler32.OBJ "CC ''CCOPT' adler32" -
+                adler32.c zlib.h zconf.h
+$   CALL MAKE compress.OBJ "CC ''CCOPT' compress" -
+                compress.c zlib.h zconf.h
+$   CALL MAKE crc32.OBJ "CC ''CCOPT' crc32" -
+                crc32.c zlib.h zconf.h
+$   CALL MAKE deflate.OBJ "CC ''CCOPT' deflate" -
+                deflate.c deflate.h zutil.h zlib.h zconf.h
+$   CALL MAKE gzio.OBJ "CC ''CCOPT' gzio" -
+                gzio.c zutil.h zlib.h zconf.h
+$   CALL MAKE infback.OBJ "CC ''CCOPT' infback" -
+                infback.c zutil.h inftrees.h inflate.h inffast.h inffixed.h
+$   CALL MAKE inffast.OBJ "CC ''CCOPT' inffast" -
+                inffast.c zutil.h zlib.h zconf.h inffast.h
+$   CALL MAKE inflate.OBJ "CC ''CCOPT' inflate" -
+                inflate.c zutil.h zlib.h zconf.h infblock.h
+$   CALL MAKE inftrees.OBJ "CC ''CCOPT' inftrees" -
+                inftrees.c zutil.h zlib.h zconf.h inftrees.h
+$   CALL MAKE trees.OBJ "CC ''CCOPT' trees" -
+                trees.c deflate.h zutil.h zlib.h zconf.h
+$   CALL MAKE uncompr.OBJ "CC ''CCOPT' uncompr" -
+                uncompr.c zlib.h zconf.h
+$   CALL MAKE zutil.OBJ "CC ''CCOPT' zutil" -
+                zutil.c zutil.h zlib.h zconf.h
+$   write sys$output "Building Zlib ..."
+$   CALL MAKE libz.OLB "lib/crea libz.olb *.obj" *.OBJ
+$   write sys$output "Building example..."
+$   CALL MAKE example.OBJ "CC ''CCOPT' example" -
+                example.c zlib.h zconf.h
+$   call make example.exe "LINK example,libz.olb/lib" example.obj libz.olb
+$   if f$search("x11vms:xvmsutils.olb") .nes. ""
+$   then
+$     write sys$output "Building minigzip..."
+$     CALL MAKE minigzip.OBJ "CC ''CCOPT' minigzip" -
+                minigzip.c zlib.h zconf.h
+$     call make minigzip.exe -
+                "LINK minigzip,libz.olb/lib,x11vms:xvmsutils.olb/lib" -
+                minigzip.obj libz.olb
+$   endif
+$  else
+$   gosub crea_mms
+$   SAY "Make ''name' ''version' with ''Make' "
+$   'make'
+$  endif
+$!
+$! Alpha gets a shareable image
+$!
+$ If axp
+$ Then
+$   gosub crea_olist
+$   write sys$output "Creating libzshr.exe"
+$   call anal_obj_axp modules.opt _link.opt
+$   if s_case
+$   then
+$      open/append optf modules.opt
+$      write optf "case_sensitive=YES"
+$      close optf
+$   endif
+$   LINK_'lopts'/SHARE=libzshr.exe modules.opt/opt,_link.opt/opt
+$ endif
+$ write sys$output "Zlib build completed"
+$ exit
+$CC_ERR:
+$ write sys$output "C compiler required to build ''name'"
+$ goto err_exit
+$ERR_EXIT:
+$ set message/facil/ident/sever/text
+$ write sys$output "Exiting..."
+$ exit 2
+$!
+$!
+$MAKE: SUBROUTINE   !SUBROUTINE TO CHECK DEPENDENCIES
+$ V = 'F$Verify(0)
+$! P1 = What we are trying to make
+$! P2 = Command to make it
+$! P3 - P8  What it depends on
+$
+$ If F$Search(P1) .Eqs. "" Then Goto Makeit
+$ Time = F$CvTime(F$File(P1,"RDT"))
+$arg=3
+$Loop:
+$       Argument = P'arg
+$       If Argument .Eqs. "" Then Goto Exit
+$       El=0
+$Loop2:
+$       File = F$Element(El," ",Argument)
+$       If File .Eqs. " " Then Goto Endl
+$       AFile = ""
+$Loop3:
+$       OFile = AFile
+$       AFile = F$Search(File)
+$       If AFile .Eqs. "" .Or. AFile .Eqs. OFile Then Goto NextEl
+$       If F$CvTime(F$File(AFile,"RDT")) .Ges. Time Then Goto Makeit
+$       Goto Loop3
+$NextEL:
+$       El = El + 1
+$       Goto Loop2
+$EndL:
+$ arg=arg+1
+$ If arg .Le. 8 Then Goto Loop
+$ Goto Exit
+$
+$Makeit:
+$ VV=F$VERIFY(0)
+$ write sys$output P2
+$ 'P2
+$ VV='F$Verify(VV)
+$Exit:
+$ If V Then Set Verify
+$ENDSUBROUTINE
+$!------------------------------------------------------------------------------
+$!
+$! Check command line options and set symbols accordingly
+$!
+$ CHECK_OPTS:
+$ i = 1
+$ OPT_LOOP:
+$ if i .lt. 9
+$ then
+$   cparm = f$edit(p'i',"upcase")
+$   if cparm .eqs. "DEBUG"
+$   then
+$     ccopt = ccopt + "/noopt/deb"
+$     lopts = lopts + "/deb"
+$   endif
+$   if f$locate("CCOPT=",cparm) .lt. f$length(cparm)
+$   then
+$     start = f$locate("=",cparm) + 1
+$     len   = f$length(cparm) - start
+$     ccopt = ccopt + f$extract(start,len,cparm)
+$     if f$locate("AS_IS",f$edit(ccopt,"UPCASE")) .lt. f$length(ccopt) -
+         then s_case = true
+$   endif
+$   if cparm .eqs. "LINK" then linkonly = true
+$   if f$locate("LOPTS=",cparm) .lt. f$length(cparm)
+$   then
+$     start = f$locate("=",cparm) + 1
+$     len   = f$length(cparm) - start
+$     lopts = lopts + f$extract(start,len,cparm)
+$   endif
+$   if f$locate("CC=",cparm) .lt. f$length(cparm)
+$   then
+$     start  = f$locate("=",cparm) + 1
+$     len    = f$length(cparm) - start
+$     cc_com = f$extract(start,len,cparm)
+      if (cc_com .nes. "DECC") .and. -
+         (cc_com .nes. "VAXC") .and. -
+	 (cc_com .nes. "GNUC")
+$     then
+$       write sys$output "Unsupported compiler choice ''cc_com' ignored"
+$       write sys$output "Use DECC, VAXC, or GNUC instead"
+$     else
+$     	if cc_com .eqs. "DECC" then its_decc = true
+$     	if cc_com .eqs. "VAXC" then its_vaxc = true
+$     	if cc_com .eqs. "GNUC" then its_gnuc = true
+$     endif
+$   endif
+$   if f$locate("MAKE=",cparm) .lt. f$length(cparm)
+$   then
+$     start  = f$locate("=",cparm) + 1
+$     len    = f$length(cparm) - start
+$     mmks = f$extract(start,len,cparm)
+$     if (mmks .eqs. "MMK") .or. (mmks .eqs. "MMS")
+$     then
+$       make = mmks
+$     else
+$       write sys$output "Unsupported make choice ''mmks' ignored"
+$       write sys$output "Use MMK or MMS instead"
+$     endif
+$   endif
+$   i = i + 1
+$   goto opt_loop
+$ endif
+$ return
+$!------------------------------------------------------------------------------
+$!
+$! Look for the compiler used
+$!
+$CHECK_COMPILER:
+$ if (.not. (its_decc .or. its_vaxc .or. its_gnuc))
+$ then
+$   its_decc = (f$search("SYS$SYSTEM:DECC$COMPILER.EXE") .nes. "")
+$   its_vaxc = .not. its_decc .and. (F$Search("SYS$System:VAXC.Exe") .nes. "")
+$   its_gnuc = .not. (its_decc .or. its_vaxc) .and. (f$trnlnm("gnu_cc") .nes. "")
+$ endif
+$!
+$! Exit if no compiler available
+$!
+$ if (.not. (its_decc .or. its_vaxc .or. its_gnuc))
+$ then goto CC_ERR
+$ else
+$   if its_decc then write sys$output "CC compiler check ... Compaq C"
+$   if its_vaxc then write sys$output "CC compiler check ... VAX C"
+$   if its_gnuc then write sys$output "CC compiler check ... GNU C"
+$ endif
+$ return
+$!------------------------------------------------------------------------------
+$!
+$! If MMS/MMK are available dump out the descrip.mms if required
+$!
+$CREA_MMS:
+$ write sys$output "Creating descrip.mms..."
+$ create descrip.mms
+$ open/append out descrip.mms
+$ copy sys$input: out
+$ deck
+# descrip.mms: MMS description file for building zlib on VMS
+# written by Martin P.J. Zinser
+# <zinser@zinser.no-ip.info or zinser@sysdev.deutsche-boerse.com>
+
+OBJS = adler32.obj, compress.obj, crc32.obj, gzio.obj, uncompr.obj, infback.obj\
+       deflate.obj, trees.obj, zutil.obj, inflate.obj, \
+       inftrees.obj, inffast.obj
+
+$ eod
+$ write out "CFLAGS=", ccopt
+$ write out "LOPTS=", lopts
+$ copy sys$input: out
+$ deck
+
+all : example.exe minigzip.exe libz.olb
+        @ write sys$output " Example applications available"
+
+libz.olb : libz.olb($(OBJS))
+	@ write sys$output " libz available"
+
+example.exe : example.obj libz.olb
+              link $(LOPTS) example,libz.olb/lib
+
+minigzip.exe : minigzip.obj libz.olb
+              link $(LOPTS) minigzip,libz.olb/lib,x11vms:xvmsutils.olb/lib
+
+clean :
+	delete *.obj;*,libz.olb;*,*.opt;*,*.exe;*
+
+
+# Other dependencies.
+adler32.obj  : adler32.c zutil.h zlib.h zconf.h
+compress.obj : compress.c zlib.h zconf.h
+crc32.obj    : crc32.c zutil.h zlib.h zconf.h
+deflate.obj  : deflate.c deflate.h zutil.h zlib.h zconf.h
+example.obj  : example.c zlib.h zconf.h
+gzio.obj     : gzio.c zutil.h zlib.h zconf.h
+inffast.obj  : inffast.c zutil.h zlib.h zconf.h inftrees.h inffast.h
+inflate.obj  : inflate.c zutil.h zlib.h zconf.h
+inftrees.obj : inftrees.c zutil.h zlib.h zconf.h inftrees.h
+minigzip.obj : minigzip.c zlib.h zconf.h
+trees.obj    : trees.c deflate.h zutil.h zlib.h zconf.h
+uncompr.obj  : uncompr.c zlib.h zconf.h
+zutil.obj    : zutil.c zutil.h zlib.h zconf.h
+infback.obj  : infback.c zutil.h inftrees.h inflate.h inffast.h inffixed.h
+$ eod
+$ close out
+$ return
+$!------------------------------------------------------------------------------
+$!
+$! Read list of core library sources from makefile.in and create options
+$! needed to build shareable image
+$!
+$CREA_OLIST:
+$ open/read min makefile.in
+$ open/write mod modules.opt
+$ src_check = "OBJS ="
+$MRLOOP:
+$ read/end=mrdone min rec
+$ if (f$extract(0,6,rec) .nes. src_check) then goto mrloop
+$ rec = rec - src_check
+$ gosub extra_filnam
+$ if (f$element(1,"\",rec) .eqs. "\") then goto mrdone
+$MRSLOOP:
+$ read/end=mrdone min rec
+$ gosub extra_filnam
+$ if (f$element(1,"\",rec) .nes. "\") then goto mrsloop
+$MRDONE:
+$ close min
+$ close mod
+$ return
+$!------------------------------------------------------------------------------
+$!
+$! Take record extracted in crea_olist and split it into single filenames
+$!
+$EXTRA_FILNAM:
+$ myrec = f$edit(rec - "\", "trim,compress")
+$ i = 0
+$FELOOP:
+$ srcfil = f$element(i," ", myrec)
+$ if (srcfil .nes. " ")
+$ then
+$   write mod f$parse(srcfil,,,"NAME"), ".obj"
+$   i = i + 1
+$   goto feloop
+$ endif
+$ return
+$!------------------------------------------------------------------------------
+$!
+$! Find current Zlib version number
+$!
+$FIND_VERSION:
+$ open/read h_in 'v_file'
+$hloop:
+$ read/end=hdone h_in rec
+$ rec = f$edit(rec,"TRIM")
+$ if (f$extract(0,1,rec) .nes. "#") then goto hloop
+$ rec = f$edit(rec - "#", "TRIM")
+$ if f$element(0," ",rec) .nes. "define" then goto hloop
+$ if f$element(1," ",rec) .eqs. v_string
+$ then
+$   version = 'f$element(2," ",rec)'
+$   goto hdone
+$ endif
+$ goto hloop
+$hdone:
+$ close h_in
+$ return
+$!------------------------------------------------------------------------------
+$!
+$! Analyze Object files for OpenVMS AXP to extract Procedure and Data
+$! information to build a symbol vector for a shareable image
+$! All the "brains" of this logic was suggested by Hartmut Becker
+$! (Hartmut.Becker@compaq.com). All the bugs were introduced by me
+$! (zinser@decus.de), so if you do have problem reports please do not
+$! bother Hartmut/HP, but get in touch with me
+$!
+$ ANAL_OBJ_AXP: Subroutine
+$ V = 'F$Verify(0)
+$ SAY := "WRITE_ SYS$OUTPUT"
+$
+$ IF F$SEARCH("''P1'") .EQS. ""
+$ THEN
+$    SAY "ANAL_OBJ_AXP-E-NOSUCHFILE:  Error, inputfile ''p1' not available"
+$    goto exit_aa
+$ ENDIF
+$ IF "''P2'" .EQS. ""
+$ THEN
+$    SAY "ANAL_OBJ_AXP:  Error, no output file provided"
+$    goto exit_aa
+$ ENDIF
+$
+$ open/read in 'p1
+$ create a.tmp
+$ open/append atmp a.tmp
+$ loop:
+$ read/end=end_loop in line
+$ f= f$search(line)
+$ if f .eqs. ""
+$ then
+$	write sys$output "ANAL_OBJ_AXP-w-nosuchfile, ''line'"
+$	goto loop
+$ endif
+$ define/user sys$output nl:
+$ define/user sys$error nl:
+$ anal/obj/gsd 'f /out=x.tmp
+$ open/read xtmp x.tmp
+$ XLOOP:
+$ read/end=end_xloop xtmp xline
+$ xline = f$edit(xline,"compress")
+$ write atmp xline
+$ goto xloop
+$ END_XLOOP:
+$ close xtmp
+$ goto loop
+$ end_loop:
+$ close in
+$ close atmp
+$ if f$search("a.tmp") .eqs. "" -
+	then $ exit
+$ ! all global definitions
+$ search a.tmp "symbol:","EGSY$V_DEF 1","EGSY$V_NORM 1"/out=b.tmp
+$ ! all procedures
+$ search b.tmp "EGSY$V_NORM 1"/wind=(0,1) /out=c.tmp
+$ search c.tmp "symbol:"/out=d.tmp
+$ define/user sys$output nl:
+$ edito/edt/command=sys$input d.tmp
+sub/symbol: "/symbol_vector=(/whole
+sub/"/=PROCEDURE)/whole
+exit
+$ ! all data
+$ search b.tmp "EGSY$V_DEF 1"/wind=(0,1) /out=e.tmp
+$ search e.tmp "symbol:"/out=f.tmp
+$ define/user sys$output nl:
+$ edito/edt/command=sys$input f.tmp
+sub/symbol: "/symbol_vector=(/whole
+sub/"/=DATA)/whole
+exit
+$ sort/nodupl d.tmp,f.tmp 'p2'
+$ delete a.tmp;*,b.tmp;*,c.tmp;*,d.tmp;*,e.tmp;*,f.tmp;*
+$ if f$search("x.tmp") .nes. "" -
+	then $ delete x.tmp;*
+$!
+$ EXIT_AA:
+$ if V then set verify
+$ endsubroutine
+$!------------------------------------------------------------------------------
diff --git a/gs/zlib/minigzip.c b/gs/zlib/minigzip.c
new file mode 100644
index 000000000..4524b96a1
--- /dev/null
+++ b/gs/zlib/minigzip.c
@@ -0,0 +1,322 @@
+/* minigzip.c -- simulate gzip using the zlib compression library
+ * Copyright (C) 1995-2005 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/*
+ * minigzip is a minimal implementation of the gzip utility. This is
+ * only an example of using zlib and isn't meant to replace the
+ * full-featured gzip. No attempt is made to deal with file systems
+ * limiting names to 14 or 8+3 characters, etc... Error checking is
+ * very limited. So use minigzip only for testing; use gzip for the
+ * real thing. On MSDOS, use only on file names without extension
+ * or in pipe mode.
+ */
+
+/* @(#) $Id$ */
+
+#include <stdio.h>
+#include "zlib.h"
+
+#ifdef STDC
+#  include <string.h>
+#  include <stdlib.h>
+#endif
+
+#ifdef USE_MMAP
+#  include <sys/types.h>
+#  include <sys/mman.h>
+#  include <sys/stat.h>
+#endif
+
+#if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(__CYGWIN__)
+#  include <fcntl.h>
+#  include <io.h>
+#  define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
+#else
+#  define SET_BINARY_MODE(file)
+#endif
+
+#ifdef VMS
+#  define unlink delete
+#  define GZ_SUFFIX "-gz"
+#endif
+#ifdef RISCOS
+#  define unlink remove
+#  define GZ_SUFFIX "-gz"
+#  define fileno(file) file->__file
+#endif
+#if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
+#  include <unix.h> /* for fileno */
+#endif
+
+#ifndef WIN32 /* unlink already in stdio.h for WIN32 */
+  extern int unlink OF((const char *));
+#endif
+
+#ifndef GZ_SUFFIX
+#  define GZ_SUFFIX ".gz"
+#endif
+#define SUFFIX_LEN (sizeof(GZ_SUFFIX)-1)
+
+#define BUFLEN      16384
+#define MAX_NAME_LEN 1024
+
+#ifdef MAXSEG_64K
+#  define local static
+   /* Needed for systems with limitation on stack size. */
+#else
+#  define local
+#endif
+
+char *prog;
+
+void error            OF((const char *msg));
+void gz_compress      OF((FILE   *in, gzFile out));
+#ifdef USE_MMAP
+int  gz_compress_mmap OF((FILE   *in, gzFile out));
+#endif
+void gz_uncompress    OF((gzFile in, FILE   *out));
+void file_compress    OF((char  *file, char *mode));
+void file_uncompress  OF((char  *file));
+int  main             OF((int argc, char *argv[]));
+
+/* ===========================================================================
+ * Display error message and exit
+ */
+void error(msg)
+    const char *msg;
+{
+    fprintf(stderr, "%s: %s\n", prog, msg);
+    exit(1);
+}
+
+/* ===========================================================================
+ * Compress input to output then close both files.
+ */
+
+void gz_compress(in, out)
+    FILE   *in;
+    gzFile out;
+{
+    local char buf[BUFLEN];
+    int len;
+    int err;
+
+#ifdef USE_MMAP
+    /* Try first compressing with mmap. If mmap fails (minigzip used in a
+     * pipe), use the normal fread loop.
+     */
+    if (gz_compress_mmap(in, out) == Z_OK) return;
+#endif
+    for (;;) {
+        len = (int)fread(buf, 1, sizeof(buf), in);
+        if (ferror(in)) {
+            perror("fread");
+            exit(1);
+        }
+        if (len == 0) break;
+
+        if (gzwrite(out, buf, (unsigned)len) != len) error(gzerror(out, &err));
+    }
+    fclose(in);
+    if (gzclose(out) != Z_OK) error("failed gzclose");
+}
+
+#ifdef USE_MMAP /* MMAP version, Miguel Albrecht <malbrech@eso.org> */
+
+/* Try compressing the input file at once using mmap. Return Z_OK if
+ * if success, Z_ERRNO otherwise.
+ */
+int gz_compress_mmap(in, out)
+    FILE   *in;
+    gzFile out;
+{
+    int len;
+    int err;
+    int ifd = fileno(in);
+    caddr_t buf;    /* mmap'ed buffer for the entire input file */
+    off_t buf_len;  /* length of the input file */
+    struct stat sb;
+
+    /* Determine the size of the file, needed for mmap: */
+    if (fstat(ifd, &sb) < 0) return Z_ERRNO;
+    buf_len = sb.st_size;
+    if (buf_len <= 0) return Z_ERRNO;
+
+    /* Now do the actual mmap: */
+    buf = mmap((caddr_t) 0, buf_len, PROT_READ, MAP_SHARED, ifd, (off_t)0);
+    if (buf == (caddr_t)(-1)) return Z_ERRNO;
+
+    /* Compress the whole file at once: */
+    len = gzwrite(out, (char *)buf, (unsigned)buf_len);
+
+    if (len != (int)buf_len) error(gzerror(out, &err));
+
+    munmap(buf, buf_len);
+    fclose(in);
+    if (gzclose(out) != Z_OK) error("failed gzclose");
+    return Z_OK;
+}
+#endif /* USE_MMAP */
+
+/* ===========================================================================
+ * Uncompress input to output then close both files.
+ */
+void gz_uncompress(in, out)
+    gzFile in;
+    FILE   *out;
+{
+    local char buf[BUFLEN];
+    int len;
+    int err;
+
+    for (;;) {
+        len = gzread(in, buf, sizeof(buf));
+        if (len < 0) error (gzerror(in, &err));
+        if (len == 0) break;
+
+        if ((int)fwrite(buf, 1, (unsigned)len, out) != len) {
+            error("failed fwrite");
+        }
+    }
+    if (fclose(out)) error("failed fclose");
+
+    if (gzclose(in) != Z_OK) error("failed gzclose");
+}
+
+
+/* ===========================================================================
+ * Compress the given file: create a corresponding .gz file and remove the
+ * original.
+ */
+void file_compress(file, mode)
+    char  *file;
+    char  *mode;
+{
+    local char outfile[MAX_NAME_LEN];
+    FILE  *in;
+    gzFile out;
+
+    strcpy(outfile, file);
+    strcat(outfile, GZ_SUFFIX);
+
+    in = fopen(file, "rb");
+    if (in == NULL) {
+        perror(file);
+        exit(1);
+    }
+    out = gzopen(outfile, mode);
+    if (out == NULL) {
+        fprintf(stderr, "%s: can't gzopen %s\n", prog, outfile);
+        exit(1);
+    }
+    gz_compress(in, out);
+
+    unlink(file);
+}
+
+
+/* ===========================================================================
+ * Uncompress the given file and remove the original.
+ */
+void file_uncompress(file)
+    char  *file;
+{
+    local char buf[MAX_NAME_LEN];
+    char *infile, *outfile;
+    FILE  *out;
+    gzFile in;
+    uInt len = (uInt)strlen(file);
+
+    strcpy(buf, file);
+
+    if (len > SUFFIX_LEN && strcmp(file+len-SUFFIX_LEN, GZ_SUFFIX) == 0) {
+        infile = file;
+        outfile = buf;
+        outfile[len-3] = '\0';
+    } else {
+        outfile = file;
+        infile = buf;
+        strcat(infile, GZ_SUFFIX);
+    }
+    in = gzopen(infile, "rb");
+    if (in == NULL) {
+        fprintf(stderr, "%s: can't gzopen %s\n", prog, infile);
+        exit(1);
+    }
+    out = fopen(outfile, "wb");
+    if (out == NULL) {
+        perror(file);
+        exit(1);
+    }
+
+    gz_uncompress(in, out);
+
+    unlink(infile);
+}
+
+
+/* ===========================================================================
+ * Usage:  minigzip [-d] [-f] [-h] [-r] [-1 to -9] [files...]
+ *   -d : decompress
+ *   -f : compress with Z_FILTERED
+ *   -h : compress with Z_HUFFMAN_ONLY
+ *   -r : compress with Z_RLE
+ *   -1 to -9 : compression level
+ */
+
+int main(argc, argv)
+    int argc;
+    char *argv[];
+{
+    int uncompr = 0;
+    gzFile file;
+    char outmode[20];
+
+    strcpy(outmode, "wb6 ");
+
+    prog = argv[0];
+    argc--, argv++;
+
+    while (argc > 0) {
+      if (strcmp(*argv, "-d") == 0)
+        uncompr = 1;
+      else if (strcmp(*argv, "-f") == 0)
+        outmode[3] = 'f';
+      else if (strcmp(*argv, "-h") == 0)
+        outmode[3] = 'h';
+      else if (strcmp(*argv, "-r") == 0)
+        outmode[3] = 'R';
+      else if ((*argv)[0] == '-' && (*argv)[1] >= '1' && (*argv)[1] <= '9' &&
+               (*argv)[2] == 0)
+        outmode[2] = (*argv)[1];
+      else
+        break;
+      argc--, argv++;
+    }
+    if (outmode[3] == ' ')
+        outmode[3] = 0;
+    if (argc == 0) {
+        SET_BINARY_MODE(stdin);
+        SET_BINARY_MODE(stdout);
+        if (uncompr) {
+            file = gzdopen(fileno(stdin), "rb");
+            if (file == NULL) error("can't gzdopen stdin");
+            gz_uncompress(file, stdout);
+        } else {
+            file = gzdopen(fileno(stdout), outmode);
+            if (file == NULL) error("can't gzdopen stdout");
+            gz_compress(stdin, file);
+        }
+    } else {
+        do {
+            if (uncompr) {
+                file_uncompress(*argv);
+            } else {
+                file_compress(*argv, outmode);
+            }
+        } while (argv++, --argc);
+    }
+    return 0;
+}
diff --git a/gs/zlib/msdos/Makefile.bor b/gs/zlib/msdos/Makefile.bor
new file mode 100644
index 000000000..8f8132d12
--- /dev/null
+++ b/gs/zlib/msdos/Makefile.bor
@@ -0,0 +1,109 @@
+# Makefile for zlib
+# Borland C++
+# Last updated: 15-Mar-2003
+
+# To use, do "make -fmakefile.bor"
+# To compile in small model, set below: MODEL=s
+
+# WARNING: the small model is supported but only for small values of
+# MAX_WBITS and MAX_MEM_LEVEL. For example:
+#    -DMAX_WBITS=11 -DDEF_WBITS=11 -DMAX_MEM_LEVEL=3
+# If you wish to reduce the memory requirements (default 256K for big
+# objects plus a few K), you can add to the LOC macro below:
+#   -DMAX_MEM_LEVEL=7 -DMAX_WBITS=14
+# See zconf.h for details about the memory requirements.
+
+# ------------ Turbo C++, Borland C++ ------------
+
+#    Optional nonstandard preprocessor flags (e.g. -DMAX_MEM_LEVEL=7)
+#    should be added to the environment via "set LOCAL_ZLIB=-DFOO" or added
+#    to the declaration of LOC here:
+LOC = $(LOCAL_ZLIB)
+
+# type for CPU required: 0: 8086, 1: 80186, 2: 80286, 3: 80386, etc.
+CPU_TYP = 0
+
+# memory model: one of s, m, c, l (small, medium, compact, large)
+MODEL=l
+
+# replace bcc with tcc for Turbo C++ 1.0, with bcc32 for the 32 bit version
+CC=bcc
+LD=bcc
+AR=tlib
+
+# compiler flags
+# replace "-O2" by "-O -G -a -d" for Turbo C++ 1.0
+CFLAGS=-O2 -Z -m$(MODEL) $(LOC)
+
+LDFLAGS=-m$(MODEL) -f-
+
+
+# variables
+ZLIB_LIB = zlib_$(MODEL).lib
+
+OBJ1 = adler32.obj compress.obj crc32.obj deflate.obj gzio.obj infback.obj
+OBJ2 = inffast.obj inflate.obj inftrees.obj trees.obj uncompr.obj zutil.obj
+OBJP1 = +adler32.obj+compress.obj+crc32.obj+deflate.obj+gzio.obj+infback.obj
+OBJP2 = +inffast.obj+inflate.obj+inftrees.obj+trees.obj+uncompr.obj+zutil.obj
+
+
+# targets
+all: $(ZLIB_LIB) example.exe minigzip.exe
+
+.c.obj:
+	$(CC) -c $(CFLAGS) $*.c
+
+adler32.obj: adler32.c zlib.h zconf.h
+
+compress.obj: compress.c zlib.h zconf.h
+
+crc32.obj: crc32.c zlib.h zconf.h crc32.h
+
+deflate.obj: deflate.c deflate.h zutil.h zlib.h zconf.h
+
+gzio.obj: gzio.c zutil.h zlib.h zconf.h
+
+infback.obj: infback.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inffast.obj: inffast.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h
+
+inflate.obj: inflate.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inftrees.obj: inftrees.c zutil.h zlib.h zconf.h inftrees.h
+
+trees.obj: trees.c zutil.h zlib.h zconf.h deflate.h trees.h
+
+uncompr.obj: uncompr.c zlib.h zconf.h
+
+zutil.obj: zutil.c zutil.h zlib.h zconf.h
+
+example.obj: example.c zlib.h zconf.h
+
+minigzip.obj: minigzip.c zlib.h zconf.h
+
+
+# the command line is cut to fit in the MS-DOS 128 byte limit:
+$(ZLIB_LIB): $(OBJ1) $(OBJ2)
+	-del $(ZLIB_LIB)
+	$(AR) $(ZLIB_LIB) $(OBJP1)
+	$(AR) $(ZLIB_LIB) $(OBJP2)
+
+example.exe: example.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) example.obj $(ZLIB_LIB)
+
+minigzip.exe: minigzip.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) minigzip.obj $(ZLIB_LIB)
+
+test: example.exe minigzip.exe
+	example
+	echo hello world | minigzip | minigzip -d
+
+clean:
+	-del *.obj
+	-del *.lib
+	-del *.exe
+	-del zlib_*.bak
+	-del foo.gz
diff --git a/gs/zlib/msdos/Makefile.dj2 b/gs/zlib/msdos/Makefile.dj2
new file mode 100644
index 000000000..283d1d961
--- /dev/null
+++ b/gs/zlib/msdos/Makefile.dj2
@@ -0,0 +1,104 @@
+# Makefile for zlib.  Modified for djgpp v2.0 by F. J. Donahoe, 3/15/96.
+# Copyright (C) 1995-1998 Jean-loup Gailly.
+# For conditions of distribution and use, see copyright notice in zlib.h
+
+# To compile, or to compile and test, type:
+#
+#   make -fmakefile.dj2;  make test -fmakefile.dj2
+#
+# To install libz.a, zconf.h and zlib.h in the djgpp directories, type:
+#
+#    make install -fmakefile.dj2
+#
+# after first defining LIBRARY_PATH and INCLUDE_PATH in djgpp.env as
+# in the sample below if the pattern of the DJGPP distribution is to
+# be followed.  Remember that, while <sp>'es around <=> are ignored in
+# makefiles, they are *not* in batch files or in djgpp.env.
+# - - - - -
+# [make]
+# INCLUDE_PATH=%\>;INCLUDE_PATH%%\DJDIR%\include
+# LIBRARY_PATH=%\>;LIBRARY_PATH%%\DJDIR%\lib
+# BUTT=-m486
+# - - - - -
+# Alternately, these variables may be defined below, overriding the values
+# in djgpp.env, as
+# INCLUDE_PATH=c:\usr\include
+# LIBRARY_PATH=c:\usr\lib
+
+CC=gcc
+
+#CFLAGS=-MMD -O
+#CFLAGS=-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7
+#CFLAGS=-MMD -g -DDEBUG
+CFLAGS=-MMD -O3 $(BUTT) -Wall -Wwrite-strings -Wpointer-arith -Wconversion \
+             -Wstrict-prototypes -Wmissing-prototypes
+
+# If cp.exe is available, replace "copy /Y" with "cp -fp" .
+CP=copy /Y
+# If gnu install.exe is available, replace $(CP) with ginstall.
+INSTALL=$(CP)
+# The default value of RM is "rm -f."  If "rm.exe" is found, comment out:
+RM=del
+LDLIBS=-L. -lz
+LD=$(CC) -s -o
+LDSHARED=$(CC)
+
+INCL=zlib.h zconf.h
+LIBS=libz.a
+
+AR=ar rcs
+
+prefix=/usr/local
+exec_prefix = $(prefix)
+
+OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
+       zutil.o inflate.o infback.o inftrees.o inffast.o
+
+OBJA =
+# to use the asm code: make OBJA=match.o
+
+TEST_OBJS = example.o minigzip.o
+
+all: example.exe minigzip.exe
+
+check: test
+test: all
+	./example
+	echo hello world | .\minigzip | .\minigzip -d
+
+%.o : %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+libz.a: $(OBJS) $(OBJA)
+	$(AR) $@ $(OBJS) $(OBJA)
+
+%.exe : %.o $(LIBS)
+	$(LD) $@ $< $(LDLIBS)
+
+# INCLUDE_PATH and LIBRARY_PATH were set for [make] in djgpp.env .
+
+.PHONY : uninstall clean
+
+install: $(INCL) $(LIBS)
+	-@if not exist $(INCLUDE_PATH)\nul mkdir $(INCLUDE_PATH)
+	-@if not exist $(LIBRARY_PATH)\nul mkdir $(LIBRARY_PATH)
+	$(INSTALL) zlib.h $(INCLUDE_PATH)
+	$(INSTALL) zconf.h $(INCLUDE_PATH)
+	$(INSTALL) libz.a $(LIBRARY_PATH)
+
+uninstall:
+	$(RM) $(INCLUDE_PATH)\zlib.h
+	$(RM) $(INCLUDE_PATH)\zconf.h
+	$(RM) $(LIBRARY_PATH)\libz.a
+
+clean:
+	$(RM) *.d
+	$(RM) *.o
+	$(RM) *.exe
+	$(RM) libz.a
+	$(RM) foo.gz
+
+DEPS := $(wildcard *.d)
+ifneq ($(DEPS),)
+include $(DEPS)
+endif
diff --git a/gs/zlib/msdos/Makefile.emx b/gs/zlib/msdos/Makefile.emx
new file mode 100644
index 000000000..ed4c31fbb
--- /dev/null
+++ b/gs/zlib/msdos/Makefile.emx
@@ -0,0 +1,69 @@
+# Makefile for zlib.  Modified for emx 0.9c by Chr. Spieler, 6/17/98.
+# Copyright (C) 1995-1998 Jean-loup Gailly.
+# For conditions of distribution and use, see copyright notice in zlib.h
+
+# To compile, or to compile and test, type:
+#
+#   make -fmakefile.emx;  make test -fmakefile.emx
+#
+
+CC=gcc
+
+#CFLAGS=-MMD -O
+#CFLAGS=-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7
+#CFLAGS=-MMD -g -DDEBUG
+CFLAGS=-MMD -O3 $(BUTT) -Wall -Wwrite-strings -Wpointer-arith -Wconversion \
+             -Wstrict-prototypes -Wmissing-prototypes
+
+# If cp.exe is available, replace "copy /Y" with "cp -fp" .
+CP=copy /Y
+# If gnu install.exe is available, replace $(CP) with ginstall.
+INSTALL=$(CP)
+# The default value of RM is "rm -f."  If "rm.exe" is found, comment out:
+RM=del
+LDLIBS=-L. -lzlib
+LD=$(CC) -s -o
+LDSHARED=$(CC)
+
+INCL=zlib.h zconf.h
+LIBS=zlib.a
+
+AR=ar rcs
+
+prefix=/usr/local
+exec_prefix = $(prefix)
+
+OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
+       zutil.o inflate.o infback.o inftrees.o inffast.o
+
+TEST_OBJS = example.o minigzip.o
+
+all: example.exe minigzip.exe
+
+test: all
+	./example
+	echo hello world | .\minigzip | .\minigzip -d
+
+%.o : %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+zlib.a: $(OBJS)
+	$(AR) $@ $(OBJS)
+
+%.exe : %.o $(LIBS)
+	$(LD) $@ $< $(LDLIBS)
+
+
+.PHONY : clean
+
+clean:
+	$(RM) *.d
+	$(RM) *.o
+	$(RM) *.exe
+	$(RM) zlib.a
+	$(RM) foo.gz
+
+DEPS := $(wildcard *.d)
+ifneq ($(DEPS),)
+include $(DEPS)
+endif
diff --git a/gs/zlib/msdos/Makefile.msc b/gs/zlib/msdos/Makefile.msc
new file mode 100644
index 000000000..b8fc665ef
--- /dev/null
+++ b/gs/zlib/msdos/Makefile.msc
@@ -0,0 +1,106 @@
+# Makefile for zlib
+# Microsoft C 5.1 or later
+# Last updated: 19-Mar-2003
+
+# To use, do "make makefile.msc"
+# To compile in small model, set below: MODEL=S
+
+# If you wish to reduce the memory requirements (default 256K for big
+# objects plus a few K), you can add to the LOC macro below:
+#   -DMAX_MEM_LEVEL=7 -DMAX_WBITS=14
+# See zconf.h for details about the memory requirements.
+
+# ------------- Microsoft C 5.1 and later -------------
+
+#    Optional nonstandard preprocessor flags (e.g. -DMAX_MEM_LEVEL=7)
+#    should be added to the environment via "set LOCAL_ZLIB=-DFOO" or added
+#    to the declaration of LOC here:
+LOC = $(LOCAL_ZLIB)
+
+# Type for CPU required: 0: 8086, 1: 80186, 2: 80286, 3: 80386, etc.
+CPU_TYP = 0
+
+# Memory model: one of S, M, C, L (small, medium, compact, large)
+MODEL=L
+
+CC=cl
+CFLAGS=-nologo -A$(MODEL) -G$(CPU_TYP) -W3 -Oait -Gs $(LOC)
+#-Ox generates bad code with MSC 5.1
+LIB_CFLAGS=-Zl $(CFLAGS)
+
+LD=link
+LDFLAGS=/noi/e/st:0x1500/noe/farcall/packcode
+# "/farcall/packcode" are only useful for `large code' memory models
+# but should be a "no-op" for small code models.
+
+
+# variables
+ZLIB_LIB = zlib_$(MODEL).lib
+
+OBJ1 = adler32.obj compress.obj crc32.obj deflate.obj gzio.obj infback.obj
+OBJ2 = inffast.obj inflate.obj inftrees.obj trees.obj uncompr.obj zutil.obj
+
+
+# targets
+all:  $(ZLIB_LIB) example.exe minigzip.exe
+
+.c.obj:
+	$(CC) -c $(LIB_CFLAGS) $*.c
+
+adler32.obj: adler32.c zlib.h zconf.h
+
+compress.obj: compress.c zlib.h zconf.h
+
+crc32.obj: crc32.c zlib.h zconf.h crc32.h
+
+deflate.obj: deflate.c deflate.h zutil.h zlib.h zconf.h
+
+gzio.obj: gzio.c zutil.h zlib.h zconf.h
+
+infback.obj: infback.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inffast.obj: inffast.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h
+
+inflate.obj: inflate.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inftrees.obj: inftrees.c zutil.h zlib.h zconf.h inftrees.h
+
+trees.obj: trees.c zutil.h zlib.h zconf.h deflate.h trees.h
+
+uncompr.obj: uncompr.c zlib.h zconf.h
+
+zutil.obj: zutil.c zutil.h zlib.h zconf.h
+
+example.obj: example.c zlib.h zconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+minigzip.obj: minigzip.c zlib.h zconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+
+# the command line is cut to fit in the MS-DOS 128 byte limit:
+$(ZLIB_LIB): $(OBJ1) $(OBJ2)
+	if exist $(ZLIB_LIB) del $(ZLIB_LIB)
+	lib $(ZLIB_LIB) $(OBJ1);
+	lib $(ZLIB_LIB) $(OBJ2);
+
+example.exe: example.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) example.obj,,,$(ZLIB_LIB);
+
+minigzip.exe: minigzip.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) minigzip.obj,,,$(ZLIB_LIB);
+
+test: example.exe minigzip.exe
+	example
+	echo hello world | minigzip | minigzip -d
+
+clean:
+	-del *.obj
+	-del *.lib
+	-del *.exe
+	-del *.map
+	-del zlib_*.bak
+	-del foo.gz
diff --git a/gs/zlib/msdos/Makefile.tc b/gs/zlib/msdos/Makefile.tc
new file mode 100644
index 000000000..480750ade
--- /dev/null
+++ b/gs/zlib/msdos/Makefile.tc
@@ -0,0 +1,94 @@
+# Makefile for zlib
+# Turbo C 2.01, Turbo C++ 1.01
+# Last updated: 15-Mar-2003
+
+# To use, do "make -fmakefile.tc"
+# To compile in small model, set below: MODEL=s
+
+# WARNING: the small model is supported but only for small values of
+# MAX_WBITS and MAX_MEM_LEVEL. For example:
+#    -DMAX_WBITS=11 -DMAX_MEM_LEVEL=3
+# If you wish to reduce the memory requirements (default 256K for big
+# objects plus a few K), you can add to CFLAGS below:
+#   -DMAX_MEM_LEVEL=7 -DMAX_WBITS=14
+# See zconf.h for details about the memory requirements.
+
+# ------------ Turbo C 2.01, Turbo C++ 1.01 ------------
+MODEL=l
+CC=tcc
+LD=tcc
+AR=tlib
+# CFLAGS=-O2 -G -Z -m$(MODEL) -DMAX_WBITS=11 -DMAX_MEM_LEVEL=3
+CFLAGS=-O2 -G -Z -m$(MODEL)
+LDFLAGS=-m$(MODEL) -f-
+
+
+# variables
+ZLIB_LIB = zlib_$(MODEL).lib
+
+OBJ1 = adler32.obj compress.obj crc32.obj deflate.obj gzio.obj infback.obj
+OBJ2 = inffast.obj inflate.obj inftrees.obj trees.obj uncompr.obj zutil.obj
+OBJP1 = +adler32.obj+compress.obj+crc32.obj+deflate.obj+gzio.obj+infback.obj
+OBJP2 = +inffast.obj+inflate.obj+inftrees.obj+trees.obj+uncompr.obj+zutil.obj
+
+
+# targets
+all: $(ZLIB_LIB) example.exe minigzip.exe
+
+.c.obj:
+	$(CC) -c $(CFLAGS) $*.c
+
+adler32.obj: adler32.c zlib.h zconf.h
+
+compress.obj: compress.c zlib.h zconf.h
+
+crc32.obj: crc32.c zlib.h zconf.h crc32.h
+
+deflate.obj: deflate.c deflate.h zutil.h zlib.h zconf.h
+
+gzio.obj: gzio.c zutil.h zlib.h zconf.h
+
+infback.obj: infback.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inffast.obj: inffast.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h
+
+inflate.obj: inflate.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inftrees.obj: inftrees.c zutil.h zlib.h zconf.h inftrees.h
+
+trees.obj: trees.c zutil.h zlib.h zconf.h deflate.h trees.h
+
+uncompr.obj: uncompr.c zlib.h zconf.h
+
+zutil.obj: zutil.c zutil.h zlib.h zconf.h
+
+example.obj: example.c zlib.h zconf.h
+
+minigzip.obj: minigzip.c zlib.h zconf.h
+
+
+# the command line is cut to fit in the MS-DOS 128 byte limit:
+$(ZLIB_LIB): $(OBJ1) $(OBJ2)
+	-del $(ZLIB_LIB)
+	$(AR) $(ZLIB_LIB) $(OBJP1)
+	$(AR) $(ZLIB_LIB) $(OBJP2)
+
+example.exe: example.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) example.obj $(ZLIB_LIB)
+
+minigzip.exe: minigzip.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) minigzip.obj $(ZLIB_LIB)
+
+test: example.exe minigzip.exe
+	example
+	echo hello world | minigzip | minigzip -d
+
+clean:
+	-del *.obj
+	-del *.lib
+	-del *.exe
+	-del zlib_*.bak
+	-del foo.gz
diff --git a/gs/zlib/old/Makefile.riscos b/gs/zlib/old/Makefile.riscos
new file mode 100644
index 000000000..57e29d3fb
--- /dev/null
+++ b/gs/zlib/old/Makefile.riscos
@@ -0,0 +1,151 @@
+# Project:   zlib_1_03
+# Patched for zlib 1.1.2 rw@shadow.org.uk 19980430
+# test works out-of-the-box, installs `somewhere' on demand
+
+# Toolflags:
+CCflags = -c -depend !Depend -IC: -g -throwback  -DRISCOS  -fah
+C++flags = -c -depend !Depend -IC: -throwback
+Linkflags = -aif -c++ -o $@
+ObjAsmflags = -throwback -NoCache -depend !Depend
+CMHGflags =
+LibFileflags = -c -l -o $@
+Squeezeflags = -o $@
+
+# change the line below to where _you_ want the library installed.
+libdest = lib:zlib
+
+# Final targets:
+@.lib:   @.o.adler32 @.o.compress @.o.crc32 @.o.deflate @.o.gzio \
+        @.o.infblock @.o.infcodes @.o.inffast @.o.inflate @.o.inftrees @.o.infutil @.o.trees \
+        @.o.uncompr @.o.zutil
+        LibFile $(LibFileflags) @.o.adler32 @.o.compress @.o.crc32 @.o.deflate \
+        @.o.gzio @.o.infblock @.o.infcodes @.o.inffast @.o.inflate @.o.inftrees @.o.infutil \
+        @.o.trees @.o.uncompr @.o.zutil
+test:   @.minigzip @.example @.lib
+	@copy @.lib @.libc  A~C~DF~L~N~P~Q~RS~TV
+	@echo running tests: hang on.
+	@/@.minigzip -f -9 libc
+	@/@.minigzip -d libc-gz
+	@/@.minigzip -f -1 libc
+	@/@.minigzip -d libc-gz
+	@/@.minigzip -h -9 libc
+	@/@.minigzip -d libc-gz
+	@/@.minigzip -h -1 libc
+	@/@.minigzip -d libc-gz
+	@/@.minigzip -9 libc
+	@/@.minigzip -d libc-gz
+	@/@.minigzip -1 libc
+	@/@.minigzip -d libc-gz
+	@diff @.lib @.libc
+	@echo that should have reported '@.lib and @.libc identical' if you have diff.
+	@/@.example @.fred @.fred
+	@echo that will have given lots of hello!'s.
+
+@.minigzip:   @.o.minigzip @.lib C:o.Stubs
+        Link $(Linkflags) @.o.minigzip @.lib C:o.Stubs
+@.example:   @.o.example @.lib C:o.Stubs
+        Link $(Linkflags) @.o.example @.lib C:o.Stubs
+
+install: @.lib
+	cdir $(libdest)
+	cdir $(libdest).h
+	@copy @.h.zlib $(libdest).h.zlib A~C~DF~L~N~P~Q~RS~TV
+	@copy @.h.zconf $(libdest).h.zconf A~C~DF~L~N~P~Q~RS~TV
+	@copy @.lib $(libdest).lib  A~C~DF~L~N~P~Q~RS~TV
+	@echo okay, installed zlib in $(libdest)
+
+clean:; remove @.minigzip
+	remove @.example
+	remove @.libc
+	-wipe @.o.* F~r~cV
+	remove @.fred
+
+# User-editable dependencies:
+.c.o:
+        cc $(ccflags) -o $@ $<
+
+# Static dependencies:
+
+# Dynamic dependencies:
+o.example:	c.example
+o.example:	h.zlib
+o.example:	h.zconf
+o.minigzip:	c.minigzip
+o.minigzip:	h.zlib
+o.minigzip:	h.zconf
+o.adler32:	c.adler32
+o.adler32:	h.zlib
+o.adler32:	h.zconf
+o.compress:	c.compress
+o.compress:	h.zlib
+o.compress:	h.zconf
+o.crc32:	c.crc32
+o.crc32:	h.zlib
+o.crc32:	h.zconf
+o.deflate:	c.deflate
+o.deflate:	h.deflate
+o.deflate:	h.zutil
+o.deflate:	h.zlib
+o.deflate:	h.zconf
+o.gzio:	c.gzio
+o.gzio:	h.zutil
+o.gzio:	h.zlib
+o.gzio:	h.zconf
+o.infblock:	c.infblock
+o.infblock:	h.zutil
+o.infblock:	h.zlib
+o.infblock:	h.zconf
+o.infblock:	h.infblock
+o.infblock:	h.inftrees
+o.infblock:	h.infcodes
+o.infblock:	h.infutil
+o.infcodes:	c.infcodes
+o.infcodes:	h.zutil
+o.infcodes:	h.zlib
+o.infcodes:	h.zconf
+o.infcodes:	h.inftrees
+o.infcodes:	h.infblock
+o.infcodes:	h.infcodes
+o.infcodes:	h.infutil
+o.infcodes:	h.inffast
+o.inffast:	c.inffast
+o.inffast:	h.zutil
+o.inffast:	h.zlib
+o.inffast:	h.zconf
+o.inffast:	h.inftrees
+o.inffast:	h.infblock
+o.inffast:	h.infcodes
+o.inffast:	h.infutil
+o.inffast:	h.inffast
+o.inflate:	c.inflate
+o.inflate:	h.zutil
+o.inflate:	h.zlib
+o.inflate:	h.zconf
+o.inflate:	h.infblock
+o.inftrees:	c.inftrees
+o.inftrees:	h.zutil
+o.inftrees:	h.zlib
+o.inftrees:	h.zconf
+o.inftrees:	h.inftrees
+o.inftrees:	h.inffixed
+o.infutil:	c.infutil
+o.infutil:	h.zutil
+o.infutil:	h.zlib
+o.infutil:	h.zconf
+o.infutil:	h.infblock
+o.infutil:	h.inftrees
+o.infutil:	h.infcodes
+o.infutil:	h.infutil
+o.trees:	c.trees
+o.trees:	h.deflate
+o.trees:	h.zutil
+o.trees:	h.zlib
+o.trees:	h.zconf
+o.trees:	h.trees
+o.uncompr:	c.uncompr
+o.uncompr:	h.zlib
+o.uncompr:	h.zconf
+o.zutil:	c.zutil
+o.zutil:	h.zutil
+o.zutil:	h.zlib
+o.zutil:	h.zconf
diff --git a/gs/zlib/old/README b/gs/zlib/old/README
new file mode 100644
index 000000000..800bf0798
--- /dev/null
+++ b/gs/zlib/old/README
@@ -0,0 +1,3 @@
+This directory contains files that have not been updated for zlib 1.2.x
+
+(Volunteers are encouraged to help clean this up.  Thanks.)
diff --git a/gs/zlib/old/descrip.mms b/gs/zlib/old/descrip.mms
new file mode 100644
index 000000000..7066da5b5
--- /dev/null
+++ b/gs/zlib/old/descrip.mms
@@ -0,0 +1,48 @@
+# descrip.mms: MMS description file for building zlib on VMS
+# written by Martin P.J. Zinser <m.zinser@gsi.de>
+
+cc_defs =
+c_deb =
+
+.ifdef __DECC__
+pref = /prefix=all
+.endif
+
+OBJS = adler32.obj, compress.obj, crc32.obj, gzio.obj, uncompr.obj,\
+       deflate.obj, trees.obj, zutil.obj, inflate.obj, infblock.obj,\
+       inftrees.obj, infcodes.obj, infutil.obj, inffast.obj
+
+CFLAGS= $(C_DEB) $(CC_DEFS) $(PREF)
+
+all : example.exe minigzip.exe
+        @ write sys$output " Example applications available"
+libz.olb : libz.olb($(OBJS))
+	@ write sys$output " libz available"
+
+example.exe : example.obj libz.olb
+              link example,libz.olb/lib
+
+minigzip.exe : minigzip.obj libz.olb
+              link minigzip,libz.olb/lib,x11vms:xvmsutils.olb/lib
+
+clean :
+	delete *.obj;*,libz.olb;*
+
+
+# Other dependencies.
+adler32.obj : zutil.h zlib.h zconf.h
+compress.obj : zlib.h zconf.h
+crc32.obj : zutil.h zlib.h zconf.h
+deflate.obj : deflate.h zutil.h zlib.h zconf.h
+example.obj : zlib.h zconf.h
+gzio.obj : zutil.h zlib.h zconf.h
+infblock.obj : zutil.h zlib.h zconf.h infblock.h inftrees.h infcodes.h infutil.h
+infcodes.obj : zutil.h zlib.h zconf.h inftrees.h infutil.h infcodes.h inffast.h
+inffast.obj : zutil.h zlib.h zconf.h inftrees.h infutil.h inffast.h
+inflate.obj : zutil.h zlib.h zconf.h infblock.h
+inftrees.obj : zutil.h zlib.h zconf.h inftrees.h
+infutil.obj : zutil.h zlib.h zconf.h inftrees.h infutil.h
+minigzip.obj : zlib.h zconf.h
+trees.obj : deflate.h zutil.h zlib.h zconf.h
+uncompr.obj : zlib.h zconf.h
+zutil.obj : zutil.h zlib.h zconf.h
diff --git a/gs/zlib/old/os2/Makefile.os2 b/gs/zlib/old/os2/Makefile.os2
new file mode 100644
index 000000000..a105aaa5b
--- /dev/null
+++ b/gs/zlib/old/os2/Makefile.os2
@@ -0,0 +1,136 @@
+# Makefile for zlib under OS/2 using GCC (PGCC)
+# For conditions of distribution and use, see copyright notice in zlib.h
+
+# To compile and test, type:
+#   cp Makefile.os2 ..
+#   cd ..
+#   make -f Makefile.os2 test
+
+# This makefile will build a static library z.lib, a shared library
+# z.dll and a import library zdll.lib. You can use either z.lib or
+# zdll.lib by specifying either -lz or -lzdll on gcc's command line
+
+CC=gcc -Zomf -s
+
+CFLAGS=-O6 -Wall
+#CFLAGS=-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7
+#CFLAGS=-g -DDEBUG
+#CFLAGS=-O3 -Wall -Wwrite-strings -Wpointer-arith -Wconversion \
+#           -Wstrict-prototypes -Wmissing-prototypes
+
+#################### BUG WARNING: #####################
+## infcodes.c hits a bug in pgcc-1.0, so you have to use either
+## -O# where # <= 4 or one of (-fno-ommit-frame-pointer or -fno-force-mem)
+## This bug is reportedly fixed in pgcc >1.0, but this was not tested
+CFLAGS+=-fno-force-mem
+
+LDFLAGS=-s -L. -lzdll -Zcrtdll
+LDSHARED=$(CC) -s -Zomf -Zdll -Zcrtdll
+
+VER=1.1.0
+ZLIB=z.lib
+SHAREDLIB=z.dll
+SHAREDLIBIMP=zdll.lib
+LIBS=$(ZLIB) $(SHAREDLIB) $(SHAREDLIBIMP)
+
+AR=emxomfar cr
+IMPLIB=emximp
+RANLIB=echo
+TAR=tar
+SHELL=bash
+
+prefix=/usr/local
+exec_prefix = $(prefix)
+
+OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
+       zutil.o inflate.o infblock.o inftrees.o infcodes.o infutil.o inffast.o
+
+TEST_OBJS = example.o minigzip.o
+
+DISTFILES = README INDEX ChangeLog configure Make*[a-z0-9] *.[ch] descrip.mms \
+  algorithm.txt zlib.3 msdos/Make*[a-z0-9] msdos/zlib.def msdos/zlib.rc \
+  nt/Makefile.nt nt/zlib.dnt  contrib/README.contrib contrib/*.txt \
+  contrib/asm386/*.asm contrib/asm386/*.c \
+  contrib/asm386/*.bat contrib/asm386/zlibvc.d?? contrib/iostream/*.cpp \
+  contrib/iostream/*.h  contrib/iostream2/*.h contrib/iostream2/*.cpp \
+  contrib/untgz/Makefile contrib/untgz/*.c contrib/untgz/*.w32
+
+all: example.exe minigzip.exe
+
+test: all
+	@LD_LIBRARY_PATH=.:$(LD_LIBRARY_PATH) ; export LD_LIBRARY_PATH; \
+	echo hello world | ./minigzip | ./minigzip -d || \
+	  echo '		*** minigzip test FAILED ***' ; \
+	if ./example; then \
+	  echo '		*** zlib test OK ***'; \
+	else \
+	  echo '		*** zlib test FAILED ***'; \
+	fi
+
+$(ZLIB): $(OBJS)
+	$(AR) $@ $(OBJS)
+	-@ ($(RANLIB) $@ || true) >/dev/null 2>&1
+
+$(SHAREDLIB): $(OBJS) os2/z.def
+	$(LDSHARED) -o $@ $^
+
+$(SHAREDLIBIMP): os2/z.def
+	$(IMPLIB) -o $@ $^
+
+example.exe: example.o $(LIBS)
+	$(CC) $(CFLAGS) -o $@ example.o $(LDFLAGS)
+
+minigzip.exe: minigzip.o $(LIBS)
+	$(CC) $(CFLAGS) -o $@ minigzip.o $(LDFLAGS)
+
+clean:
+	rm -f *.o *~ example minigzip libz.a libz.so* foo.gz
+
+distclean:	clean
+
+zip:
+	mv Makefile Makefile~; cp -p Makefile.in Makefile
+	rm -f test.c ztest*.c
+	v=`sed -n -e 's/\.//g' -e '/VERSION "/s/.*"\(.*\)".*/\1/p' < zlib.h`;\
+	zip -ul9 zlib$$v $(DISTFILES)
+	mv Makefile~ Makefile
+
+dist:
+	mv Makefile Makefile~; cp -p Makefile.in Makefile
+	rm -f test.c ztest*.c
+	d=zlib-`sed -n '/VERSION "/s/.*"\(.*\)".*/\1/p' < zlib.h`;\
+	rm -f $$d.tar.gz; \
+	if test ! -d ../$$d; then rm -f ../$$d; ln -s `pwd` ../$$d; fi; \
+	files=""; \
+	for f in $(DISTFILES); do files="$$files $$d/$$f"; done; \
+	cd ..; \
+	GZIP=-9 $(TAR) chofz $$d/$$d.tar.gz $$files; \
+	if test ! -d $$d; then rm -f $$d; fi
+	mv Makefile~ Makefile
+
+tags:
+	etags *.[ch]
+
+depend:
+	makedepend -- $(CFLAGS) -- *.[ch]
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+adler32.o: zlib.h zconf.h
+compress.o: zlib.h zconf.h
+crc32.o: zlib.h zconf.h
+deflate.o: deflate.h zutil.h zlib.h zconf.h
+example.o: zlib.h zconf.h
+gzio.o: zutil.h zlib.h zconf.h
+infblock.o: infblock.h inftrees.h infcodes.h infutil.h zutil.h zlib.h zconf.h
+infcodes.o: zutil.h zlib.h zconf.h
+infcodes.o: inftrees.h infblock.h infcodes.h infutil.h inffast.h
+inffast.o: zutil.h zlib.h zconf.h inftrees.h
+inffast.o: infblock.h infcodes.h infutil.h inffast.h
+inflate.o: zutil.h zlib.h zconf.h infblock.h
+inftrees.o: zutil.h zlib.h zconf.h inftrees.h
+infutil.o: zutil.h zlib.h zconf.h infblock.h inftrees.h infcodes.h infutil.h
+minigzip.o: zlib.h zconf.h
+trees.o: deflate.h zutil.h zlib.h zconf.h trees.h
+uncompr.o: zlib.h zconf.h
+zutil.o: zutil.h zlib.h zconf.h
diff --git a/gs/zlib/old/os2/zlib.def b/gs/zlib/old/os2/zlib.def
new file mode 100644
index 000000000..4c753f1a3
--- /dev/null
+++ b/gs/zlib/old/os2/zlib.def
@@ -0,0 +1,51 @@
+;
+; Slightly modified version of ../nt/zlib.dnt :-)
+;
+
+LIBRARY		Z
+DESCRIPTION	"Zlib compression library for OS/2"
+CODE		PRELOAD MOVEABLE DISCARDABLE
+DATA		PRELOAD MOVEABLE MULTIPLE
+
+EXPORTS
+    adler32
+    compress
+    crc32
+    deflate
+    deflateCopy
+    deflateEnd
+    deflateInit2_
+    deflateInit_
+    deflateParams
+    deflateReset
+    deflateSetDictionary
+    gzclose
+    gzdopen
+    gzerror
+    gzflush
+    gzopen
+    gzread
+    gzwrite
+    inflate
+    inflateEnd
+    inflateInit2_
+    inflateInit_
+    inflateReset
+    inflateSetDictionary
+    inflateSync
+    uncompress
+    zlibVersion
+    gzprintf
+    gzputc
+    gzgetc
+    gzseek
+    gzrewind
+    gztell
+    gzeof
+    gzsetparams
+    zError
+    inflateSyncPoint
+    get_crc_table
+    compress2
+    gzputs
+    gzgets
diff --git a/gs/zlib/old/visual-basic.txt b/gs/zlib/old/visual-basic.txt
new file mode 100644
index 000000000..57efe5812
--- /dev/null
+++ b/gs/zlib/old/visual-basic.txt
@@ -0,0 +1,160 @@
+See below some functions declarations for Visual Basic.
+
+Frequently Asked Question:
+
+Q: Each time I use the compress function I get the -5 error (not enough
+   room in the output buffer).
+
+A: Make sure that the length of the compressed buffer is passed by
+   reference ("as any"), not by value ("as long"). Also check that
+   before the call of compress this length is equal to the total size of
+   the compressed buffer and not zero.
+
+
+From: "Jon Caruana" <jon-net@usa.net>
+Subject: Re: How to port zlib declares to vb?
+Date: Mon, 28 Oct 1996 18:33:03 -0600
+
+Got the answer! (I haven't had time to check this but it's what I got, and
+looks correct):
+
+He has the following routines working:
+        compress
+        uncompress
+        gzopen
+        gzwrite
+        gzread
+        gzclose
+
+Declares follow: (Quoted from Carlos Rios <c_rios@sonda.cl>, in Vb4 form)
+
+#If Win16 Then   'Use Win16 calls.
+Declare Function compress Lib "ZLIB.DLL" (ByVal compr As
+        String, comprLen As Any, ByVal buf As String, ByVal buflen
+        As Long) As Integer
+Declare Function uncompress Lib "ZLIB.DLL" (ByVal uncompr
+        As String, uncomprLen As Any, ByVal compr As String, ByVal
+        lcompr As Long) As Integer
+Declare Function gzopen Lib "ZLIB.DLL" (ByVal filePath As
+        String, ByVal mode As String) As Long
+Declare Function gzread Lib "ZLIB.DLL" (ByVal file As
+        Long, ByVal uncompr As String, ByVal uncomprLen As Integer)
+        As Integer
+Declare Function gzwrite Lib "ZLIB.DLL" (ByVal file As
+        Long, ByVal uncompr As String, ByVal uncomprLen As Integer)
+        As Integer
+Declare Function gzclose Lib "ZLIB.DLL" (ByVal file As
+        Long) As Integer
+#Else
+Declare Function compress Lib "ZLIB32.DLL"
+        (ByVal compr As String, comprLen As Any, ByVal buf As
+        String, ByVal buflen As Long) As Integer
+Declare Function uncompress Lib "ZLIB32.DLL"
+        (ByVal uncompr As String, uncomprLen As Any, ByVal compr As
+        String, ByVal lcompr As Long) As Long
+Declare Function gzopen Lib "ZLIB32.DLL"
+        (ByVal file As String, ByVal mode As String) As Long
+Declare Function gzread Lib "ZLIB32.DLL"
+        (ByVal file As Long, ByVal uncompr As String, ByVal
+        uncomprLen As Long) As Long
+Declare Function gzwrite Lib "ZLIB32.DLL"
+        (ByVal file As Long, ByVal uncompr As String, ByVal
+        uncomprLen As Long) As Long
+Declare Function gzclose Lib "ZLIB32.DLL"
+        (ByVal file As Long) As Long
+#End If
+
+-Jon Caruana
+jon-net@usa.net
+Microsoft Sitebuilder Network Level 1 Member - HTML Writer's Guild Member
+
+
+Here is another example from Michael <michael_borgsys@hotmail.com> that he
+says conforms to the VB guidelines, and that solves the problem of not
+knowing the uncompressed size by storing it at the end of the file:
+
+'Calling the functions:
+'bracket meaning: <parameter> [optional] {Range of possible values}
+'Call subCompressFile(<path with filename to compress> [, <path with
+filename to write to>, [level of compression {1..9}]])
+'Call subUncompressFile(<path with filename to compress>)
+
+Option Explicit
+Private lngpvtPcnSml As Long 'Stores value for 'lngPercentSmaller'
+Private Const SUCCESS As Long = 0
+Private Const strFilExt As String = ".cpr"
+Private Declare Function lngfncCpr Lib "zlib.dll" Alias "compress2" (ByRef
+dest As Any, ByRef destLen As Any, ByRef src As Any, ByVal srcLen As Long,
+ByVal level As Integer) As Long
+Private Declare Function lngfncUcp Lib "zlib.dll" Alias "uncompress" (ByRef
+dest As Any, ByRef destLen As Any, ByRef src As Any, ByVal srcLen As Long)
+As Long
+
+Public Sub subCompressFile(ByVal strargOriFilPth As String, Optional ByVal
+strargCprFilPth As String, Optional ByVal intLvl As Integer = 9)
+    Dim strCprPth As String
+    Dim lngOriSiz As Long
+    Dim lngCprSiz As Long
+    Dim bytaryOri() As Byte
+    Dim bytaryCpr() As Byte
+    lngOriSiz = FileLen(strargOriFilPth)
+    ReDim bytaryOri(lngOriSiz - 1)
+    Open strargOriFilPth For Binary Access Read As #1
+        Get #1, , bytaryOri()
+    Close #1
+    strCprPth = IIf(strargCprFilPth = "", strargOriFilPth, strargCprFilPth)
+'Select file path and name
+    strCprPth = strCprPth & IIf(Right(strCprPth, Len(strFilExt)) =
+strFilExt, "", strFilExt) 'Add file extension if not exists
+    lngCprSiz = (lngOriSiz * 1.01) + 12 'Compression needs temporary a bit
+more space then original file size
+    ReDim bytaryCpr(lngCprSiz - 1)
+    If lngfncCpr(bytaryCpr(0), lngCprSiz, bytaryOri(0), lngOriSiz, intLvl) =
+SUCCESS Then
+        lngpvtPcnSml = (1# - (lngCprSiz / lngOriSiz)) * 100
+        ReDim Preserve bytaryCpr(lngCprSiz - 1)
+        Open strCprPth For Binary Access Write As #1
+            Put #1, , bytaryCpr()
+            Put #1, , lngOriSiz 'Add the the original size value to the end
+(last 4 bytes)
+        Close #1
+    Else
+        MsgBox "Compression error"
+    End If
+    Erase bytaryCpr
+    Erase bytaryOri
+End Sub
+
+Public Sub subUncompressFile(ByVal strargFilPth As String)
+    Dim bytaryCpr() As Byte
+    Dim bytaryOri() As Byte
+    Dim lngOriSiz As Long
+    Dim lngCprSiz As Long
+    Dim strOriPth As String
+    lngCprSiz = FileLen(strargFilPth)
+    ReDim bytaryCpr(lngCprSiz - 1)
+    Open strargFilPth For Binary Access Read As #1
+        Get #1, , bytaryCpr()
+    Close #1
+    'Read the original file size value:
+    lngOriSiz = bytaryCpr(lngCprSiz - 1) * (2 ^ 24) _
+              + bytaryCpr(lngCprSiz - 2) * (2 ^ 16) _
+              + bytaryCpr(lngCprSiz - 3) * (2 ^ 8) _
+              + bytaryCpr(lngCprSiz - 4)
+    ReDim Preserve bytaryCpr(lngCprSiz - 5) 'Cut of the original size value
+    ReDim bytaryOri(lngOriSiz - 1)
+    If lngfncUcp(bytaryOri(0), lngOriSiz, bytaryCpr(0), lngCprSiz) = SUCCESS
+Then
+        strOriPth = Left(strargFilPth, Len(strargFilPth) - Len(strFilExt))
+        Open strOriPth For Binary Access Write As #1
+            Put #1, , bytaryOri()
+        Close #1
+    Else
+        MsgBox "Uncompression error"
+    End If
+    Erase bytaryCpr
+    Erase bytaryOri
+End Sub
+Public Property Get lngPercentSmaller() As Long
+    lngPercentSmaller = lngpvtPcnSml
+End Property
diff --git a/gs/zlib/old/zlib.html b/gs/zlib/old/zlib.html
new file mode 100644
index 000000000..8c1b190c3
--- /dev/null
+++ b/gs/zlib/old/zlib.html
@@ -0,0 +1,971 @@
+<html>
+<head>
+ <title>
+ zlib general purpose compression library version 1.1.4
+ </title>
+</head>
+<body bgcolor="White" text="Black" vlink="Red" alink="Navy" link="Red">
+<!-- background="zlibbg.gif" -->
+
+<h1> zlib 1.1.4 Manual </h1>
+<hr>
+<a name="Contents"><h2>Contents</h2>
+<ol type="I">
+<li> <a href="#Prologue">Prologue</a>
+<li> <a href="#Introduction">Introduction</a>
+<li> <a href="#Utility functions">Utility functions</a>
+<li> <a href="#Basic functions">Basic functions</a>
+<li> <a href="#Advanced functions">Advanced functions</a>
+<li> <a href="#Constants">Constants</a>
+<li> <a href="#struct z_stream_s">struct z_stream_s</a>
+<li> <a href="#Checksum functions">Checksum functions</a>
+<li> <a href="#Misc">Misc</a>
+</ol>
+<hr>
+<a name="Prologue"><h2> Prologue </h2>
+  'zlib' general purpose compression library version 1.1.4, March 11th, 2002
+  <p>
+  Copyright (C) 1995-2002 Jean-loup Gailly and Mark Adler
+  <p>
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+  <p>
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+  <ol>
+   <li> The origin of this software must not be misrepresented ; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+   <li> Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+   <li> This notice may not be removed or altered from any source distribution.
+  </ol>
+
+  <dl>
+  <dt>Jean-loup Gailly
+  <dd><a href="mailto:jloup@gzip.org">jloup@gzip.org</a>
+  <dt>Mark Adler
+  <dd><a href="mailto:madler@alumni.caltech.edu">madler@alumni.caltech.edu</a>
+  </dl>
+
+  The data format used by the zlib library is described by RFCs (Request for
+  Comments) 1950 to 1952 in the files
+  <a href="ftp://ds.internic.net/rfc/rfc1950.txt">
+  ftp://ds.internic.net/rfc/rfc1950.txt </a>
+  (zlib format),
+  <a href="ftp://ds.internic.net/rfc/rfc1951.txt">
+  rfc1951.txt </a>
+  (<a href="#deflate">deflate</a> format) and
+  <a href="ftp://ds.internic.net/rfc/rfc1952.txt">
+  rfc1952.txt </a>
+  (gzip format).
+  <p>
+  This manual is converted from zlib.h by
+  <a href="mailto:piaip@csie.ntu.edu.tw"> piaip </a>
+  <p>
+  Visit <a href="http://ftp.cdrom.com/pub/infozip/zlib/">
+  http://ftp.cdrom.com/pub/infozip/zlib/</a>
+  for the official zlib web page.
+  <p>
+
+<hr>
+<a name="Introduction"><h2> Introduction </h2>
+     The 'zlib' compression library provides in-memory compression and
+  decompression functions, including integrity checks of the uncompressed
+  data.  This version of the library supports only one compression method
+  (deflation) but other algorithms will be added later and will have the same
+  stream interface.
+  <p>
+
+     Compression can be done in a single step if the buffers are large
+  enough (for example if an input file is mmap'ed), or can be done by
+  repeated calls of the compression function.  In the latter case, the
+  application must provide more input and/or consume the output
+  (providing more output space) before each call.
+  <p>
+
+     The library also supports reading and writing files in gzip (.gz) format
+  with an interface similar to that of stdio.
+  <p>
+
+     The library does not install any signal handler. The decoder checks
+  the consistency of the compressed data, so the library should never
+  crash even in case of corrupted input.
+  <p>
+
+<hr>
+<a name="Utility functions"><h2> Utility functions </h2>
+     The following utility functions are implemented on top of the
+   <a href="#Basic functions">basic stream-oriented functions</a>.
+   To simplify the interface, some
+   default options are assumed (compression level and memory usage,
+   standard memory allocation functions). The source code of these
+   utility functions can easily be modified if you need special options.
+<h3> Function list </h3>
+<ul>
+<li> int  <a href="#compress">compress</a> (Bytef *dest,   uLongf *destLen, const Bytef *source, uLong sourceLen);
+<li> int  <a href="#compress2">compress2</a> (Bytef *dest,   uLongf *destLen, const Bytef *source, uLong sourceLen, int level);
+<li> int  <a href="#uncompress">uncompress</a> (Bytef *dest,   uLongf *destLen, const Bytef *source, uLong sourceLen);
+<li> typedef voidp gzFile;
+<li>  gzFile  <a href="#gzopen">gzopen</a>  (const char *path, const char *mode);
+<li> gzFile  <a href="#gzdopen">gzdopen</a>  (int fd, const char *mode);
+<li> int  <a href="#gzsetparams">gzsetparams</a> (gzFile file, int level, int strategy);
+<li> int     <a href="#gzread">gzread</a>  (gzFile file, voidp buf, unsigned len);
+<li> int     <a href="#gzwrite">gzwrite</a> (gzFile file, const voidp buf, unsigned len);
+<li> int VA   <a href="#gzprintf">gzprintf</a> (gzFile file, const char *format, ...);
+<li> int  <a href="#gzputs">gzputs</a> (gzFile file, const char *s);
+<li> char *  <a href="#gzgets">gzgets</a> (gzFile file, char *buf, int len);
+<li> int     <a href="#gzputc">gzputc</a> (gzFile file, int c);
+<li> int     <a href="#gzgetc">gzgetc</a> (gzFile file);
+<li> int     <a href="#gzflush">gzflush</a> (gzFile file, int flush);
+<li> z_off_t     <a href="#gzseek">gzseek</a> (gzFile file, z_off_t offset, int whence);
+<li> z_off_t     <a href="#gztell">gztell</a> (gzFile file);
+<li> int     <a href="#gzrewind">gzrewind</a> (gzFile file);
+<li> int  <a href="#gzeof">gzeof</a> (gzFile file);
+<li> int     <a href="#gzclose">gzclose</a> (gzFile file);
+<li> const char *  <a href="#gzerror">gzerror</a> (gzFile file, int *errnum);
+</ul>
+<h3> Function description </h3>
+<dl>
+<font color="Blue"><dt> int  <a name="compress">compress</a> (Bytef *dest,   uLongf *destLen, const Bytef *source, uLong sourceLen);</font>
+<dd>
+     Compresses the source buffer into the destination buffer.  sourceLen is
+   the byte length of the source buffer. Upon entry, destLen is the total
+   size of the destination buffer, which must be at least 0.1% larger than
+   sourceLen plus 12 bytes. Upon exit, destLen is the actual size of the
+   compressed buffer.<p>
+     This function can be used to <a href="#compress">compress</a> a whole file at once if the
+   input file is mmap'ed.<p>
+     <a href="#compress">compress</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_MEM_ERROR">Z_MEM_ERROR</a> if there was not
+   enough memory, <a href="#Z_BUF_ERROR">Z_BUF_ERROR</a> if there was not enough room in the output
+   buffer.<p>
+
+<font color="Blue"><dt> int  <a name="compress2">compress2</a> (Bytef *dest,   uLongf *destLen, const Bytef *source, uLong sourceLen, int level);</font>
+<dd>
+     Compresses the source buffer into the destination buffer. The level
+   parameter has the same meaning as in <a href="#deflateInit">deflateInit</a>.  sourceLen is the byte
+   length of the source buffer. Upon entry, destLen is the total size of the
+   destination buffer, which must be at least 0.1% larger than sourceLen plus
+   12 bytes. Upon exit, destLen is the actual size of the compressed buffer.
+   <p>
+
+     <a href="#compress2">compress2</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_MEM_ERROR">Z_MEM_ERROR</a> if there was not enough
+   memory, <a href="#Z_BUF_ERROR">Z_BUF_ERROR</a> if there was not enough room in the output buffer,
+   <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if the level parameter is invalid.
+   <p>
+
+<font color="Blue"><dt> int  <a name="uncompress">uncompress</a> (Bytef *dest,   uLongf *destLen, const Bytef *source, uLong sourceLen);</font>
+<dd>
+     Decompresses the source buffer into the destination buffer.  sourceLen is
+   the byte length of the source buffer. Upon entry, destLen is the total
+   size of the destination buffer, which must be large enough to hold the
+   entire uncompressed data. (The size of the uncompressed data must have
+   been saved previously by the compressor and transmitted to the decompressor
+   by some mechanism outside the scope of this compression library.)
+   Upon exit, destLen is the actual size of the compressed buffer. <p>
+     This function can be used to decompress a whole file at once if the
+   input file is mmap'ed.
+   <p>
+
+     <a href="#uncompress">uncompress</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_MEM_ERROR">Z_MEM_ERROR</a> if there was not
+   enough memory, <a href="#Z_BUF_ERROR">Z_BUF_ERROR</a> if there was not enough room in the output
+   buffer, or <a href="#Z_DATA_ERROR">Z_DATA_ERROR</a> if the input data was corrupted.
+   <p>
+
+<dt> typedef voidp gzFile;
+<dd> <p>
+
+<font color="Blue"><dt>  gzFile  <a name="gzopen">gzopen</a>  (const char *path, const char *mode);</font>
+<dd>
+     Opens a gzip (.gz) file for reading or writing. The mode parameter
+   is as in fopen ("rb" or "wb") but can also include a compression level
+   ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for
+   Huffman only compression as in "wb1h". (See the description
+   of <a href="#deflateInit2">deflateInit2</a> for more information about the strategy parameter.)
+   <p>
+
+     <a href="#gzopen">gzopen</a> can be used to read a file which is not in gzip format ; in this
+   case <a href="#gzread">gzread</a> will directly read from the file without decompression.
+   <p>
+
+     <a href="#gzopen">gzopen</a> returns NULL if the file could not be opened or if there was
+   insufficient memory to allocate the (de)compression <a href="#state">state</a> ; errno
+   can be checked to distinguish the two cases (if errno is zero, the
+   zlib error is <a href="#Z_MEM_ERROR">Z_MEM_ERROR</a>).
+   <p>
+
+<font color="Blue"><dt> gzFile  <a name="gzdopen">gzdopen</a>  (int fd, const char *mode);</font>
+<dd>
+     <a href="#gzdopen">gzdopen</a>() associates a gzFile with the file descriptor fd.  File
+   descriptors are obtained from calls like open, dup, creat, pipe or
+   fileno (in the file has been previously opened with fopen).
+   The mode parameter is as in <a href="#gzopen">gzopen</a>.
+   <p>
+     The next call of <a href="#gzclose">gzclose</a> on the returned gzFile will also close the
+   file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
+   descriptor fd. If you want to keep fd open, use <a href="#gzdopen">gzdopen</a>(dup(fd), mode).
+   <p>
+     <a href="#gzdopen">gzdopen</a> returns NULL if there was insufficient memory to allocate
+   the (de)compression <a href="#state">state</a>.
+   <p>
+
+<font color="Blue"><dt> int  <a name="gzsetparams">gzsetparams</a> (gzFile file, int level, int strategy);</font>
+<dd>
+     Dynamically update the compression level or strategy. See the description
+   of <a href="#deflateInit2">deflateInit2</a> for the meaning of these parameters.
+   <p>
+     <a href="#gzsetparams">gzsetparams</a> returns <a href="#Z_OK">Z_OK</a> if success, or <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if the file was not
+   opened for writing.
+   <p>
+
+<font color="Blue"><dt> int     <a name="gzread">gzread</a>  (gzFile file, voidp buf, unsigned len);</font>
+<dd>
+     Reads the given number of uncompressed bytes from the compressed file.
+   If the input file was not in gzip format, <a href="#gzread">gzread</a> copies the given number
+   of bytes into the buffer.
+   <p>
+     <a href="#gzread">gzread</a> returns the number of uncompressed bytes actually read (0 for
+   end of file, -1 for error).
+   <p>
+
+<font color="Blue"><dt> int     <a name="gzwrite">gzwrite</a> (gzFile file, const voidp buf, unsigned len);</font>
+<dd>
+     Writes the given number of uncompressed bytes into the compressed file.
+   <a href="#gzwrite">gzwrite</a> returns the number of uncompressed bytes actually written
+   (0 in case of error).
+   <p>
+
+<font color="Blue"><dt> int VA   <a name="gzprintf">gzprintf</a> (gzFile file, const char *format, ...);</font>
+<dd>
+     Converts, formats, and writes the args to the compressed file under
+   control of the format string, as in fprintf. <a href="#gzprintf">gzprintf</a> returns the number of
+   uncompressed bytes actually written (0 in case of error).
+   <p>
+
+<font color="Blue"><dt> int  <a name="gzputs">gzputs</a> (gzFile file, const char *s);</font>
+<dd>
+      Writes the given null-terminated string to the compressed file, excluding
+   the terminating null character.
+   <p>
+      <a href="#gzputs">gzputs</a> returns the number of characters written, or -1 in case of error.
+      <p>
+
+<font color="Blue"><dt> char *  <a name="gzgets">gzgets</a> (gzFile file, char *buf, int len);</font>
+<dd>
+      Reads bytes from the compressed file until len-1 characters are read, or
+   a newline character is read and transferred to buf, or an end-of-file
+   condition is encountered.  The string is then terminated with a null
+   character.
+   <p>
+      <a href="#gzgets">gzgets</a> returns buf, or <a href="#Z_NULL">Z_NULL</a> in case of error.
+      <p>
+
+<font color="Blue"><dt> int     <a name="gzputc">gzputc</a> (gzFile file, int c);</font>
+<dd>
+      Writes c, converted to an unsigned char, into the compressed file.
+   <a href="#gzputc">gzputc</a> returns the value that was written, or -1 in case of error.
+   <p>
+
+<font color="Blue"><dt> int     <a name="gzgetc">gzgetc</a> (gzFile file);</font>
+<dd>
+      Reads one byte from the compressed file. <a href="#gzgetc">gzgetc</a> returns this byte
+   or -1 in case of end of file or error.
+   <p>
+
+<font color="Blue"><dt> int     <a name="gzflush">gzflush</a> (gzFile file, int flush);</font>
+<dd>
+     Flushes all pending output into the compressed file. The parameter
+   flush is as in the <a href="#deflate">deflate</a>() function. The return value is the zlib
+   error number (see function <a href="#gzerror">gzerror</a> below). <a href="#gzflush">gzflush</a> returns <a href="#Z_OK">Z_OK</a> if
+   the flush parameter is <a href="#Z_FINISH">Z_FINISH</a> and all output could be flushed.
+   <p>
+     <a href="#gzflush">gzflush</a> should be called only when strictly necessary because it can
+   degrade compression.
+   <p>
+
+<font color="Blue"><dt> z_off_t     <a name="gzseek">gzseek</a> (gzFile file, z_off_t offset, int whence);</font>
+<dd>
+      Sets the starting position for the next <a href="#gzread">gzread</a> or <a href="#gzwrite">gzwrite</a> on the
+   given compressed file. The offset represents a number of bytes in the
+   uncompressed data stream. The whence parameter is defined as in lseek(2);
+   the value SEEK_END is not supported.
+   <p>
+     If the file is opened for reading, this function is emulated but can be
+   extremely slow. If the file is opened for writing, only forward seeks are
+   supported ; <a href="#gzseek">gzseek</a> then compresses a sequence of zeroes up to the new
+   starting position.
+   <p>
+      <a href="#gzseek">gzseek</a> returns the resulting offset location as measured in bytes from
+   the beginning of the uncompressed stream, or -1 in case of error, in
+   particular if the file is opened for writing and the new starting position
+   would be before the current position.
+   <p>
+
+<font color="Blue"><dt> int     <a name="gzrewind">gzrewind</a> (gzFile file);</font>
+<dd>
+     Rewinds the given file. This function is supported only for reading.
+     <p>
+   <a href="#gzrewind">gzrewind</a>(file) is equivalent to (int)<a href="#gzseek">gzseek</a>(file, 0L, SEEK_SET)
+   <p>
+
+<font color="Blue"><dt> z_off_t     <a name="gztell">gztell</a> (gzFile file);</font>
+<dd>
+     Returns the starting position for the next <a href="#gzread">gzread</a> or <a href="#gzwrite">gzwrite</a> on the
+   given compressed file. This position represents a number of bytes in the
+   uncompressed data stream.
+   <p>
+
+   <a href="#gztell">gztell</a>(file) is equivalent to <a href="#gzseek">gzseek</a>(file, 0L, SEEK_CUR)
+   <p>
+
+<font color="Blue"><dt> int  <a name="gzeof">gzeof</a> (gzFile file);</font>
+<dd>
+     Returns 1 when EOF has previously been detected reading the given
+   input stream, otherwise zero.
+   <p>
+
+<font color="Blue"><dt> int     <a name="gzclose">gzclose</a> (gzFile file);</font>
+<dd>
+     Flushes all pending output if necessary, closes the compressed file
+   and deallocates all the (de)compression <a href="#state">state</a>. The return value is the zlib
+   error number (see function <a href="#gzerror">gzerror</a> below).
+   <p>
+
+<font color="Blue"><dt> const char *  <a name="gzerror">gzerror</a> (gzFile file, int *errnum);</font>
+<dd>
+     Returns the error message for the last error which occurred on the
+   given compressed file. errnum is set to zlib error number. If an
+   error occurred in the file system and not in the compression library,
+   errnum is set to <a href="#Z_ERRNO">Z_ERRNO</a> and the application may consult errno
+   to get the exact error code.
+   <p>
+</dl>
+<hr>
+<a name="Basic functions"><h2> Basic functions </h2>
+<h3> Function list </h3>
+<ul>
+<li>  const char *  <a href="#zlibVersion">zlibVersion</a> (void);
+<li>  int  <a href="#deflateInit">deflateInit</a> (<a href="#z_streamp">z_streamp</a> strm, int level);
+<li>  int  <a href="#deflate">deflate</a> (<a href="#z_streamp">z_streamp</a> strm, int flush);
+<li>  int  <a href="#deflateEnd">deflateEnd</a> (<a href="#z_streamp">z_streamp</a> strm);
+<li>  int  <a href="#inflateInit">inflateInit</a> (<a href="#z_streamp">z_streamp</a> strm);
+<li>  int  <a href="#inflate">inflate</a> (<a href="#z_streamp">z_streamp</a> strm, int flush);
+<li>  int  <a href="#inflateEnd">inflateEnd</a> (<a href="#z_streamp">z_streamp</a> strm);
+</ul>
+
+<h3> Function description </h3>
+<dl>
+<font color="Blue"><dt>  const char *  <a name="zlibVersion">zlibVersion</a> (void);</font>
+<dd> The application can compare <a href="#zlibVersion">zlibVersion</a> and ZLIB_VERSION for consistency.
+   If the first character differs, the library code actually used is
+   not compatible with the zlib.h header file used by the application.
+   This check is automatically made by <a href="#deflateInit">deflateInit</a> and <a href="#inflateInit">inflateInit</a>.
+   <p>
+
+<font color="Blue"><dt> int  <a name="deflateInit">deflateInit</a> (<a href="#z_streamp">z_streamp</a> strm, int level);</font>
+<dd>
+     Initializes the internal stream <a href="#state">state</a> for compression. The fields
+   <a href="#zalloc">zalloc</a>, <a href="#zfree">zfree</a> and <a href="#opaque">opaque</a> must be initialized before by the caller.
+   If <a href="#zalloc">zalloc</a> and <a href="#zfree">zfree</a> are set to <a href="#Z_NULL">Z_NULL</a>, <a href="#deflateInit">deflateInit</a> updates them to
+   use default allocation functions.
+   <p>
+
+     The compression level must be <a href="#Z_DEFAULT_COMPRESSION">Z_DEFAULT_COMPRESSION</a>, or between 0 and 9:
+   1 gives best speed, 9 gives best compression, 0 gives no compression at
+   all (the input data is simply copied a block at a time).
+   <p>
+
+   <a href="#Z_DEFAULT_COMPRESSION">Z_DEFAULT_COMPRESSION</a> requests a default compromise between speed and
+   compression (currently equivalent to level 6).
+   <p>
+
+     <a href="#deflateInit">deflateInit</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_MEM_ERROR">Z_MEM_ERROR</a> if there was not
+   enough memory, <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if level is not a valid compression level,
+   <a href="#Z_VERSION_ERROR">Z_VERSION_ERROR</a> if the zlib library version (<a href="#zlib_version">zlib_version</a>) is incompatible
+   with the version assumed by the caller (ZLIB_VERSION).
+   <a href="#msg">msg</a> is set to null if there is no error message.  <a href="#deflateInit">deflateInit</a> does not
+   perform any compression: this will be done by <a href="#deflate">deflate</a>().
+   <p>
+
+<font color="Blue"><dt>  int  <a name="deflate">deflate</a> (<a href="#z_streamp">z_streamp</a> strm, int flush);</font>
+<dd>
+    <a href="#deflate">deflate</a> compresses as much data as possible, and stops when the input
+  buffer becomes empty or the output buffer becomes full. It may introduce some
+  output latency (reading input without producing any output) except when
+  forced to flush.<p>
+
+    The detailed semantics are as follows. <a href="#deflate">deflate</a> performs one or both of the
+  following actions:
+
+  <ul>
+  <li> Compress more input starting at <a href="#next_in">next_in</a> and update <a href="#next_in">next_in</a> and <a href="#avail_in">avail_in</a>
+    accordingly. If not all input can be processed (because there is not
+    enough room in the output buffer), <a href="#next_in">next_in</a> and <a href="#avail_in">avail_in</a> are updated and
+    processing will resume at this point for the next call of <a href="#deflate">deflate</a>().
+
+  <li>
+    Provide more output starting at <a href="#next_out">next_out</a> and update <a href="#next_out">next_out</a> and <a href="#avail_out">avail_out</a>
+    accordingly. This action is forced if the parameter flush is non zero.
+    Forcing flush frequently degrades the compression ratio, so this parameter
+    should be set only when necessary (in interactive applications).
+    Some output may be provided even if flush is not set.
+  </ul> <p>
+
+  Before the call of <a href="#deflate">deflate</a>(), the application should ensure that at least
+  one of the actions is possible, by providing more input and/or consuming
+  more output, and updating <a href="#avail_in">avail_in</a> or <a href="#avail_out">avail_out</a> accordingly ; <a href="#avail_out">avail_out</a>
+  should never be zero before the call. The application can consume the
+  compressed output when it wants, for example when the output buffer is full
+  (<a href="#avail_out">avail_out</a> == 0), or after each call of <a href="#deflate">deflate</a>(). If <a href="#deflate">deflate</a> returns <a href="#Z_OK">Z_OK</a>
+  and with zero <a href="#avail_out">avail_out</a>, it must be called again after making room in the
+  output buffer because there might be more output pending.
+  <p>
+
+    If the parameter flush is set to <a href="#Z_SYNC_FLUSH">Z_SYNC_FLUSH</a>, all pending output is
+  flushed to the output buffer and the output is aligned on a byte boundary, so
+  that the decompressor can get all input data available so far. (In particular
+  <a href="#avail_in">avail_in</a> is zero after the call if enough output space has been provided
+  before the call.)  Flushing may degrade compression for some compression
+  algorithms and so it should be used only when necessary.
+  <p>
+
+    If flush is set to <a href="#Z_FULL_FLUSH">Z_FULL_FLUSH</a>, all output is flushed as with
+  <a href="#Z_SYNC_FLUSH">Z_SYNC_FLUSH</a>, and the compression <a href="#state">state</a> is reset so that decompression can
+  restart from this point if previous compressed data has been damaged or if
+  random access is desired. Using <a href="#Z_FULL_FLUSH">Z_FULL_FLUSH</a> too often can seriously degrade
+  the compression.
+  <p>
+
+    If <a href="#deflate">deflate</a> returns with <a href="#avail_out">avail_out</a> == 0, this function must be called again
+  with the same value of the flush parameter and more output space (updated
+  <a href="#avail_out">avail_out</a>), until the flush is complete (<a href="#deflate">deflate</a> returns with non-zero
+  <a href="#avail_out">avail_out</a>).
+  <p>
+
+    If the parameter flush is set to <a href="#Z_FINISH">Z_FINISH</a>, pending input is processed,
+  pending output is flushed and <a href="#deflate">deflate</a> returns with <a href="#Z_STREAM_END">Z_STREAM_END</a> if there
+  was enough output space ; if <a href="#deflate">deflate</a> returns with <a href="#Z_OK">Z_OK</a>, this function must be
+  called again with <a href="#Z_FINISH">Z_FINISH</a> and more output space (updated <a href="#avail_out">avail_out</a>) but no
+  more input data, until it returns with <a href="#Z_STREAM_END">Z_STREAM_END</a> or an error. After
+  <a href="#deflate">deflate</a> has returned <a href="#Z_STREAM_END">Z_STREAM_END</a>, the only possible operations on the
+  stream are <a href="#deflateReset">deflateReset</a> or <a href="#deflateEnd">deflateEnd</a>.
+  <p>
+
+    <a href="#Z_FINISH">Z_FINISH</a> can be used immediately after <a href="#deflateInit">deflateInit</a> if all the compression
+  is to be done in a single step. In this case, <a href="#avail_out">avail_out</a> must be at least
+  0.1% larger than <a href="#avail_in">avail_in</a> plus 12 bytes.  If <a href="#deflate">deflate</a> does not return
+  <a href="#Z_STREAM_END">Z_STREAM_END</a>, then it must be called again as described above.
+  <p>
+
+    <a href="#deflate">deflate</a>() sets strm-&gt <a href="#adler">adler</a> to the <a href="#adler32">adler32</a> checksum of all input read
+  so far (that is, <a href="#total_in">total_in</a> bytes).
+  <p>
+
+    <a href="#deflate">deflate</a>() may update <a href="#data_type">data_type</a> if it can make a good guess about
+  the input data type (<a href="#Z_ASCII">Z_ASCII</a> or <a href="#Z_BINARY">Z_BINARY</a>). In doubt, the data is considered
+  binary. This field is only for information purposes and does not affect
+  the compression algorithm in any manner.
+  <p>
+
+    <a href="#deflate">deflate</a>() returns <a href="#Z_OK">Z_OK</a> if some progress has been made (more input
+  processed or more output produced), <a href="#Z_STREAM_END">Z_STREAM_END</a> if all input has been
+  consumed and all output has been produced (only when flush is set to
+  <a href="#Z_FINISH">Z_FINISH</a>), <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if the stream <a href="#state">state</a> was inconsistent (for example
+  if <a href="#next_in">next_in</a> or <a href="#next_out">next_out</a> was NULL), <a href="#Z_BUF_ERROR">Z_BUF_ERROR</a> if no progress is possible
+  (for example <a href="#avail_in">avail_in</a> or <a href="#avail_out">avail_out</a> was zero).
+  <p>
+
+<font color="Blue"><dt>  int  <a name="deflateEnd">deflateEnd</a> (<a href="#z_streamp">z_streamp</a> strm);</font>
+<dd>
+     All dynamically allocated data structures for this stream are freed.
+   This function discards any unprocessed input and does not flush any
+   pending output.
+   <p>
+
+     <a href="#deflateEnd">deflateEnd</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if the
+   stream <a href="#state">state</a> was inconsistent, <a href="#Z_DATA_ERROR">Z_DATA_ERROR</a> if the stream was freed
+   prematurely (some input or output was discarded). In the error case,
+   <a href="#msg">msg</a> may be set but then points to a static string (which must not be
+   deallocated).
+   <p>
+
+<font color="Blue"><dt>  int  <a name="inflateInit">inflateInit</a> (<a href="#z_streamp">z_streamp</a> strm);</font>
+<dd>
+	Initializes the internal stream <a href="#state">state</a> for decompression. The fields
+   <a href="#next_in">next_in</a>, <a href="#avail_in">avail_in</a>, <a href="#zalloc">zalloc</a>, <a href="#zfree">zfree</a> and <a href="#opaque">opaque</a> must be initialized before by
+   the caller. If <a href="#next_in">next_in</a> is not <a href="#Z_NULL">Z_NULL</a> and <a href="#avail_in">avail_in</a> is large enough (the exact
+   value depends on the compression method), <a href="#inflateInit">inflateInit</a> determines the
+   compression method from the zlib header and allocates all data structures
+   accordingly ; otherwise the allocation will be deferred to the first call of
+   <a href="#inflate">inflate</a>.  If <a href="#zalloc">zalloc</a> and <a href="#zfree">zfree</a> are set to <a href="#Z_NULL">Z_NULL</a>, <a href="#inflateInit">inflateInit</a> updates them to
+   use default allocation functions.
+   <p>
+
+     <a href="#inflateInit">inflateInit</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_MEM_ERROR">Z_MEM_ERROR</a> if there was not enough
+   memory, <a href="#Z_VERSION_ERROR">Z_VERSION_ERROR</a> if the zlib library version is incompatible with the
+   version assumed by the caller.  <a href="#msg">msg</a> is set to null if there is no error
+   message. <a href="#inflateInit">inflateInit</a> does not perform any decompression apart from reading
+   the zlib header if present: this will be done by <a href="#inflate">inflate</a>().  (So <a href="#next_in">next_in</a> and
+   <a href="#avail_in">avail_in</a> may be modified, but <a href="#next_out">next_out</a> and <a href="#avail_out">avail_out</a> are unchanged.)
+   <p>
+
+<font color="Blue"><dt>  int  <a name="inflate">inflate</a> (<a href="#z_streamp">z_streamp</a> strm, int flush);</font>
+<dd>
+    <a href="#inflate">inflate</a> decompresses as much data as possible, and stops when the input
+  buffer becomes empty or the output buffer becomes full. It may some
+  introduce some output latency (reading input without producing any output)
+  except when forced to flush.
+  <p>
+
+  The detailed semantics are as follows. <a href="#inflate">inflate</a> performs one or both of the
+  following actions:
+
+  <ul>
+  <li> Decompress more input starting at <a href="#next_in">next_in</a> and update <a href="#next_in">next_in</a> and <a href="#avail_in">avail_in</a>
+    accordingly. If not all input can be processed (because there is not
+    enough room in the output buffer), <a href="#next_in">next_in</a> is updated and processing
+    will resume at this point for the next call of <a href="#inflate">inflate</a>().
+
+  <li> Provide more output starting at <a href="#next_out">next_out</a> and update <a href="#next_out">next_out</a> and
+    <a href="#avail_out">avail_out</a> accordingly.  <a href="#inflate">inflate</a>() provides as much output as possible,
+    until there is no more input data or no more space in the output buffer
+    (see below about the flush parameter).
+  </ul> <p>
+
+  Before the call of <a href="#inflate">inflate</a>(), the application should ensure that at least
+  one of the actions is possible, by providing more input and/or consuming
+  more output, and updating the next_* and avail_* values accordingly.
+  The application can consume the uncompressed output when it wants, for
+  example when the output buffer is full (<a href="#avail_out">avail_out</a> == 0), or after each
+  call of <a href="#inflate">inflate</a>(). If <a href="#inflate">inflate</a> returns <a href="#Z_OK">Z_OK</a> and with zero <a href="#avail_out">avail_out</a>, it
+  must be called again after making room in the output buffer because there
+  might be more output pending.
+  <p>
+
+    If the parameter flush is set to <a href="#Z_SYNC_FLUSH">Z_SYNC_FLUSH</a>, <a href="#inflate">inflate</a> flushes as much
+  output as possible to the output buffer. The flushing behavior of <a href="#inflate">inflate</a> is
+  not specified for values of the flush parameter other than <a href="#Z_SYNC_FLUSH">Z_SYNC_FLUSH</a>
+  and <a href="#Z_FINISH">Z_FINISH</a>, but the current implementation actually flushes as much output
+  as possible anyway.
+  <p>
+
+    <a href="#inflate">inflate</a>() should normally be called until it returns <a href="#Z_STREAM_END">Z_STREAM_END</a> or an
+  error. However if all decompression is to be performed in a single step
+  (a single call of <a href="#inflate">inflate</a>), the parameter flush should be set to
+  <a href="#Z_FINISH">Z_FINISH</a>. In this case all pending input is processed and all pending
+  output is flushed ; <a href="#avail_out">avail_out</a> must be large enough to hold all the
+  uncompressed data. (The size of the uncompressed data may have been saved
+  by the compressor for this purpose.) The next operation on this stream must
+  be <a href="#inflateEnd">inflateEnd</a> to deallocate the decompression <a href="#state">state</a>. The use of <a href="#Z_FINISH">Z_FINISH</a>
+  is never required, but can be used to inform <a href="#inflate">inflate</a> that a faster routine
+  may be used for the single <a href="#inflate">inflate</a>() call.
+  <p>
+
+     If a preset dictionary is needed at this point (see <a href="#inflateSetDictionary">inflateSetDictionary</a>
+  below), <a href="#inflate">inflate</a> sets strm-<a href="#adler">adler</a> to the <a href="#adler32">adler32</a> checksum of the
+  dictionary chosen by the compressor and returns <a href="#Z_NEED_DICT">Z_NEED_DICT</a> ; otherwise
+  it sets strm-&gt <a href="#adler">adler</a> to the <a href="#adler32">adler32</a> checksum of all output produced
+  so far (that is, <a href="#total_out">total_out</a> bytes) and returns <a href="#Z_OK">Z_OK</a>, <a href="#Z_STREAM_END">Z_STREAM_END</a> or
+  an error code as described below. At the end of the stream, <a href="#inflate">inflate</a>()
+  checks that its computed <a href="#adler32">adler32</a> checksum is equal to that saved by the
+  compressor and returns <a href="#Z_STREAM_END">Z_STREAM_END</a> only if the checksum is correct.
+  <p>
+
+    <a href="#inflate">inflate</a>() returns <a href="#Z_OK">Z_OK</a> if some progress has been made (more input processed
+  or more output produced), <a href="#Z_STREAM_END">Z_STREAM_END</a> if the end of the compressed data has
+  been reached and all uncompressed output has been produced, <a href="#Z_NEED_DICT">Z_NEED_DICT</a> if a
+  preset dictionary is needed at this point, <a href="#Z_DATA_ERROR">Z_DATA_ERROR</a> if the input data was
+  corrupted (input stream not conforming to the zlib format or incorrect
+  <a href="#adler32">adler32</a> checksum), <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if the stream structure was inconsistent
+  (for example if <a href="#next_in">next_in</a> or <a href="#next_out">next_out</a> was NULL), <a href="#Z_MEM_ERROR">Z_MEM_ERROR</a> if there was not
+  enough memory, <a href="#Z_BUF_ERROR">Z_BUF_ERROR</a> if no progress is possible or if there was not
+  enough room in the output buffer when <a href="#Z_FINISH">Z_FINISH</a> is used. In the <a href="#Z_DATA_ERROR">Z_DATA_ERROR</a>
+  case, the application may then call <a href="#inflateSync">inflateSync</a> to look for a good
+  compression block.
+  <p>
+
+<font color="Blue"><dt>  int  <a name="inflateEnd">inflateEnd</a> (<a href="#z_streamp">z_streamp</a> strm);</font>
+<dd>
+     All dynamically allocated data structures for this stream are freed.
+   This function discards any unprocessed input and does not flush any
+   pending output.
+   <p>
+
+     <a href="#inflateEnd">inflateEnd</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if the stream <a href="#state">state</a>
+   was inconsistent. In the error case, <a href="#msg">msg</a> may be set but then points to a
+   static string (which must not be deallocated).
+</dl>
+<hr>
+<a name="Advanced functions"><h2> Advanced functions </h2>
+    The following functions are needed only in some special applications.
+<h3> Function list </h3>
+<ul>
+<li>  int  <a href="#deflateInit2">deflateInit2</a> (<a href="#z_streamp">z_streamp</a> strm,
+<li> int  <a href="#deflateSetDictionary">deflateSetDictionary</a> (<a href="#z_streamp">z_streamp</a> strm, const Bytef *dictionary, uInt  dictLength);
+<li> int  <a href="#deflateCopy">deflateCopy</a> (<a href="#z_streamp">z_streamp</a> dest, <a href="#z_streamp">z_streamp</a> source);
+<li> int  <a href="#deflateReset">deflateReset</a> (<a href="#z_streamp">z_streamp</a> strm);
+<li> int  <a href="#deflateParams">deflateParams</a> (<a href="#z_streamp">z_streamp</a> strm, int level, int strategy);
+<li> int  <a href="#inflateInit2">inflateInit2</a> (<a href="#z_streamp">z_streamp</a> strm, int  windowBits);
+<li>  int  <a href="#inflateSetDictionary">inflateSetDictionary</a> (<a href="#z_streamp">z_streamp</a> strm, const Bytef *dictionary, uInt  dictLength);
+<li> int  <a href="#inflateSync">inflateSync</a> (<a href="#z_streamp">z_streamp</a> strm);
+<li> int  <a href="#inflateReset">inflateReset</a> (<a href="#z_streamp">z_streamp</a> strm);
+
+</ul>
+<h3> Function description </h3>
+<dl>
+<font color="Blue"><dt>  int  <a name="deflateInit2">deflateInit2</a> (<a href="#z_streamp">z_streamp</a> strm, int  level, int  method, int  windowBits, int  memLevel, int  strategy);</font>
+
+<dd> This is another version of <a href="#deflateInit">deflateInit</a> with more compression options. The
+   fields <a href="#next_in">next_in</a>, <a href="#zalloc">zalloc</a>, <a href="#zfree">zfree</a> and <a href="#opaque">opaque</a> must be initialized before by
+   the caller.<p>
+
+     The method parameter is the compression method. It must be <a href="#Z_DEFLATED">Z_DEFLATED</a> in
+   this version of the library.<p>
+
+     The windowBits parameter is the base two logarithm of the window size
+   (the size of the history buffer).  It should be in the range 8..15 for this
+   version of the library. Larger values of this parameter result in better
+   compression at the expense of memory usage. The default value is 15 if
+   <a href="#deflateInit">deflateInit</a> is used instead.<p>
+
+     The memLevel parameter specifies how much memory should be allocated
+   for the internal compression <a href="#state">state</a>. memLevel=1 uses minimum memory but
+   is slow and reduces compression ratio ; memLevel=9 uses maximum memory
+   for optimal speed. The default value is 8. See zconf.h for total memory
+   usage as a function of windowBits and memLevel.<p>
+
+     The strategy parameter is used to tune the compression algorithm. Use the
+   value <a href="#Z_DEFAULT_STRATEGY">Z_DEFAULT_STRATEGY</a> for normal data, <a href="#Z_FILTERED">Z_FILTERED</a> for data produced by a
+   filter (or predictor), or <a href="#Z_HUFFMAN_ONLY">Z_HUFFMAN_ONLY</a> to force Huffman encoding only (no
+   string match).  Filtered data consists mostly of small values with a
+   somewhat random distribution. In this case, the compression algorithm is
+   tuned to <a href="#compress">compress</a> them better. The effect of <a href="#Z_FILTERED">Z_FILTERED</a> is to force more
+   Huffman coding and less string matching ; it is somewhat intermediate
+   between Z_DEFAULT and <a href="#Z_HUFFMAN_ONLY">Z_HUFFMAN_ONLY</a>. The strategy parameter only affects
+   the compression ratio but not the correctness of the compressed output even
+   if it is not set appropriately.<p>
+
+      <a href="#deflateInit2">deflateInit2</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_MEM_ERROR">Z_MEM_ERROR</a> if there was not enough
+   memory, <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if a parameter is invalid (such as an invalid
+   method). <a href="#msg">msg</a> is set to null if there is no error message.  <a href="#deflateInit2">deflateInit2</a> does
+   not perform any compression: this will be done by <a href="#deflate">deflate</a>().<p>
+
+<font color="Blue"><dt> int  <a name="deflateSetDictionary">deflateSetDictionary</a> (<a href="#z_streamp">z_streamp</a> strm, const Bytef *dictionary, uInt  dictLength);</font>
+<dd>
+     Initializes the compression dictionary from the given byte sequence
+   without producing any compressed output. This function must be called
+   immediately after <a href="#deflateInit">deflateInit</a>, <a href="#deflateInit2">deflateInit2</a> or <a href="#deflateReset">deflateReset</a>, before any
+   call of <a href="#deflate">deflate</a>. The compressor and decompressor must use exactly the same
+   dictionary (see <a href="#inflateSetDictionary">inflateSetDictionary</a>).<p>
+
+     The dictionary should consist of strings (byte sequences) that are likely
+   to be encountered later in the data to be compressed, with the most commonly
+   used strings preferably put towards the end of the dictionary. Using a
+   dictionary is most useful when the data to be compressed is short and can be
+   predicted with good accuracy ; the data can then be compressed better than
+   with the default empty dictionary.<p>
+
+     Depending on the size of the compression data structures selected by
+   <a href="#deflateInit">deflateInit</a> or <a href="#deflateInit2">deflateInit2</a>, a part of the dictionary may in effect be
+   discarded, for example if the dictionary is larger than the window size in
+   <a href="#deflate">deflate</a> or deflate2. Thus the strings most likely to be useful should be
+   put at the end of the dictionary, not at the front.<p>
+
+     Upon return of this function, strm-&gt <a href="#adler">adler</a> is set to the Adler32 value
+   of the dictionary ; the decompressor may later use this value to determine
+   which dictionary has been used by the compressor. (The Adler32 value
+   applies to the whole dictionary even if only a subset of the dictionary is
+   actually used by the compressor.)<p>
+
+     <a href="#deflateSetDictionary">deflateSetDictionary</a> returns <a href="#Z_OK">Z_OK</a> if success, or <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if a
+   parameter is invalid (such as NULL dictionary) or the stream <a href="#state">state</a> is
+   inconsistent (for example if <a href="#deflate">deflate</a> has already been called for this stream
+   or if the compression method is bsort). <a href="#deflateSetDictionary">deflateSetDictionary</a> does not
+   perform any compression: this will be done by <a href="#deflate">deflate</a>().<p>
+
+<font color="Blue"><dt> int  <a name="deflateCopy">deflateCopy</a> (<a href="#z_streamp">z_streamp</a> dest, <a href="#z_streamp">z_streamp</a> source);</font>
+<dd>
+     Sets the destination stream as a complete copy of the source stream.<p>
+
+     This function can be useful when several compression strategies will be
+   tried, for example when there are several ways of pre-processing the input
+   data with a filter. The streams that will be discarded should then be freed
+   by calling <a href="#deflateEnd">deflateEnd</a>.  Note that <a href="#deflateCopy">deflateCopy</a> duplicates the internal
+   compression <a href="#state">state</a> which can be quite large, so this strategy is slow and
+   can consume lots of memory.<p>
+
+     <a href="#deflateCopy">deflateCopy</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_MEM_ERROR">Z_MEM_ERROR</a> if there was not
+   enough memory, <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if the source stream <a href="#state">state</a> was inconsistent
+   (such as <a href="#zalloc">zalloc</a> being NULL). <a href="#msg">msg</a> is left unchanged in both source and
+   destination.<p>
+
+<font color="Blue"><dt> int  <a name="deflateReset">deflateReset</a> (<a href="#z_streamp">z_streamp</a> strm);</font>
+<dd>     This function is equivalent to <a href="#deflateEnd">deflateEnd</a> followed by <a href="#deflateInit">deflateInit</a>,
+   but does not free and reallocate all the internal compression <a href="#state">state</a>.
+   The stream will keep the same compression level and any other attributes
+   that may have been set by <a href="#deflateInit2">deflateInit2</a>.<p>
+
+      <a href="#deflateReset">deflateReset</a> returns <a href="#Z_OK">Z_OK</a> if success, or <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if the source
+   stream <a href="#state">state</a> was inconsistent (such as <a href="#zalloc">zalloc</a> or <a href="#state">state</a> being NULL).<p>
+
+<font color="Blue"><dt> int  <a name="deflateParams">deflateParams</a> (<a href="#z_streamp">z_streamp</a> strm, int level, int strategy);</font>
+<dd>
+     Dynamically update the compression level and compression strategy.  The
+   interpretation of level and strategy is as in <a href="#deflateInit2">deflateInit2</a>.  This can be
+   used to switch between compression and straight copy of the input data, or
+   to switch to a different kind of input data requiring a different
+   strategy. If the compression level is changed, the input available so far
+   is compressed with the old level (and may be flushed); the new level will
+   take effect only at the next call of <a href="#deflate">deflate</a>().<p>
+
+     Before the call of <a href="#deflateParams">deflateParams</a>, the stream <a href="#state">state</a> must be set as for
+   a call of <a href="#deflate">deflate</a>(), since the currently available input may have to
+   be compressed and flushed. In particular, strm-&gt <a href="#avail_out">avail_out</a> must be
+   non-zero.<p>
+
+     <a href="#deflateParams">deflateParams</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if the source
+   stream <a href="#state">state</a> was inconsistent or if a parameter was invalid, <a href="#Z_BUF_ERROR">Z_BUF_ERROR</a>
+   if strm-&gtavail_out was zero.<p>
+
+<font color="Blue"><dt> int  <a name="inflateInit2">inflateInit2</a> (<a href="#z_streamp">z_streamp</a> strm, int  windowBits);</font>
+
+<dd>     This is another version of <a href="#inflateInit">inflateInit</a> with an extra parameter. The
+   fields <a href="#next_in">next_in</a>, <a href="#avail_in">avail_in</a>, <a href="#zalloc">zalloc</a>, <a href="#zfree">zfree</a> and <a href="#opaque">opaque</a> must be initialized
+   before by the caller.<p>
+
+     The windowBits parameter is the base two logarithm of the maximum window
+   size (the size of the history buffer).  It should be in the range 8..15 for
+   this version of the library. The default value is 15 if <a href="#inflateInit">inflateInit</a> is used
+   instead. If a compressed stream with a larger window size is given as
+   input, <a href="#inflate">inflate</a>() will return with the error code <a href="#Z_DATA_ERROR">Z_DATA_ERROR</a> instead of
+   trying to allocate a larger window.<p>
+
+      <a href="#inflateInit2">inflateInit2</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_MEM_ERROR">Z_MEM_ERROR</a> if there was not enough
+   memory, <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if a parameter is invalid (such as a negative
+   memLevel). <a href="#msg">msg</a> is set to null if there is no error message.  <a href="#inflateInit2">inflateInit2</a>
+   does not perform any decompression apart from reading the zlib header if
+   present: this will be done by <a href="#inflate">inflate</a>(). (So <a href="#next_in">next_in</a> and <a href="#avail_in">avail_in</a> may be
+   modified, but <a href="#next_out">next_out</a> and <a href="#avail_out">avail_out</a> are unchanged.)<p>
+
+<font color="Blue"><dt>  int  <a name="inflateSetDictionary">inflateSetDictionary</a> (<a href="#z_streamp">z_streamp</a> strm, const Bytef *dictionary, uInt  dictLength);</font>
+<dd>
+     Initializes the decompression dictionary from the given uncompressed byte
+   sequence. This function must be called immediately after a call of <a href="#inflate">inflate</a>
+   if this call returned <a href="#Z_NEED_DICT">Z_NEED_DICT</a>. The dictionary chosen by the compressor
+   can be determined from the Adler32 value returned by this call of
+   <a href="#inflate">inflate</a>. The compressor and decompressor must use exactly the same
+   dictionary (see <a href="#deflateSetDictionary">deflateSetDictionary</a>).<p>
+
+     <a href="#inflateSetDictionary">inflateSetDictionary</a> returns <a href="#Z_OK">Z_OK</a> if success, <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if a
+   parameter is invalid (such as NULL dictionary) or the stream <a href="#state">state</a> is
+   inconsistent, <a href="#Z_DATA_ERROR">Z_DATA_ERROR</a> if the given dictionary doesn't match the
+   expected one (incorrect Adler32 value). <a href="#inflateSetDictionary">inflateSetDictionary</a> does not
+   perform any decompression: this will be done by subsequent calls of
+   <a href="#inflate">inflate</a>().<p>
+
+<font color="Blue"><dt> int  <a name="inflateSync">inflateSync</a> (<a href="#z_streamp">z_streamp</a> strm);</font>
+
+<dd>    Skips invalid compressed data until a full flush point (see above the
+  description of <a href="#deflate">deflate</a> with <a href="#Z_FULL_FLUSH">Z_FULL_FLUSH</a>) can be found, or until all
+  available input is skipped. No output is provided.<p>
+
+    <a href="#inflateSync">inflateSync</a> returns <a href="#Z_OK">Z_OK</a> if a full flush point has been found, <a href="#Z_BUF_ERROR">Z_BUF_ERROR</a>
+  if no more input was provided, <a href="#Z_DATA_ERROR">Z_DATA_ERROR</a> if no flush point has been found,
+  or <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if the stream structure was inconsistent. In the success
+  case, the application may save the current current value of <a href="#total_in">total_in</a> which
+  indicates where valid compressed data was found. In the error case, the
+  application may repeatedly call <a href="#inflateSync">inflateSync</a>, providing more input each time,
+  until success or end of the input data.<p>
+
+<font color="Blue"><dt> int  <a name="inflateReset">inflateReset</a> (<a href="#z_streamp">z_streamp</a> strm);</font>
+<dd>
+     This function is equivalent to <a href="#inflateEnd">inflateEnd</a> followed by <a href="#inflateInit">inflateInit</a>,
+   but does not free and reallocate all the internal decompression <a href="#state">state</a>.
+   The stream will keep attributes that may have been set by <a href="#inflateInit2">inflateInit2</a>.
+   <p>
+
+      <a href="#inflateReset">inflateReset</a> returns <a href="#Z_OK">Z_OK</a> if success, or <a href="#Z_STREAM_ERROR">Z_STREAM_ERROR</a> if the source
+   stream <a href="#state">state</a> was inconsistent (such as <a href="#zalloc">zalloc</a> or <a href="#state">state</a> being NULL).
+   <p>
+</dl>
+
+<hr>
+<a name="Checksum functions"><h2> Checksum functions </h2>
+     These functions are not related to compression but are exported
+   anyway because they might be useful in applications using the
+   compression library.
+<h3> Function list </h3>
+<ul>
+<li> uLong  <a href="#adler32">adler32</a> (uLong <a href="#adler">adler</a>, const Bytef *buf, uInt len);
+<li> uLong  <a href="#crc32">crc32</a>   (uLong crc, const Bytef *buf, uInt len);
+</ul>
+<h3> Function description </h3>
+<dl>
+<font color="Blue"><dt> uLong  <a name="adler32">adler32</a> (uLong <a href="#adler">adler</a>, const Bytef *buf, uInt len);</font>
+<dd>
+     Update a running Adler-32 checksum with the bytes buf[0..len-1] and
+   return the updated checksum. If buf is NULL, this function returns
+   the required initial value for the checksum.
+   <p>
+   An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
+   much faster. Usage example:
+   <pre>
+
+     uLong <a href="#adler">adler</a> = <a href="#adler32">adler32</a>(0L, <a href="#Z_NULL">Z_NULL</a>, 0);
+
+     while (read_buffer(buffer, length) != EOF) {
+       <a href="#adler">adler</a> = <a href="#adler32">adler32</a>(<a href="#adler">adler</a>, buffer, length);
+     }
+     if (<a href="#adler">adler</a> != original_adler) error();
+   </pre>
+
+<font color="Blue"><dt> uLong  <a name="crc32">crc32</a>   (uLong crc, const Bytef *buf, uInt len);</font>
+<dd>
+     Update a running crc with the bytes buf[0..len-1] and return the updated
+   crc. If buf is NULL, this function returns the required initial value
+   for the crc. Pre- and post-conditioning (one's complement) is performed
+   within this function so it shouldn't be done by the application.
+   Usage example:
+   <pre>
+
+     uLong crc = <a href="#crc32">crc32</a>(0L, <a href="#Z_NULL">Z_NULL</a>, 0);
+
+     while (read_buffer(buffer, length) != EOF) {
+       crc = <a href="#crc32">crc32</a>(crc, buffer, length);
+     }
+     if (crc != original_crc) error();
+   </pre>
+</dl>
+<hr>
+<a name="struct z_stream_s"><h2> struct z_stream_s </h2>
+<font color="Blue">
+<a name="z_stream_s">
+<pre>
+typedef struct z_stream_s {
+    Bytef    *<a name="next_in">next_in</a>;  /* next input byte */
+    uInt     <a name="avail_in">avail_in</a>;  /* number of bytes available at <a href="#next_in">next_in</a> */
+    uLong    <a name="total_in">total_in</a>;  /* total nb of input bytes read so far */
+
+    Bytef    *<a name="next_out">next_out</a>; /* next output byte should be put there */
+    uInt     <a name="avail_out">avail_out</a>; /* remaining free space at <a href="#next_out">next_out</a> */
+    uLong    <a name="total_out">total_out</a>; /* total nb of bytes output so far */
+
+    char     *<a name="msg">msg</a>;      /* last error message, NULL if no error */
+    struct internal_state FAR *<a name="state">state</a>; /* not visible by applications */
+
+    alloc_func <a name="zalloc">zalloc</a>;  /* used to allocate the internal <a href="#state">state</a> */
+    free_func  <a name="zfree">zfree</a>;   /* used to free the internal <a href="#state">state</a> */
+    voidpf     <a name="opaque">opaque</a>;  /* private data object passed to <a href="#zalloc">zalloc</a> and <a href="#zfree">zfree</a> */
+
+    int     <a name="data_type">data_type</a>;  /* best guess about the data type: ascii or binary */
+    uLong   <a name="adler">adler</a>;      /* <a href="#adler32">adler32</a> value of the uncompressed data */
+    uLong   <a name="reserved">reserved</a>;   /* <a href="#reserved">reserved</a> for future use */
+} <a href="#z_stream_s">z_stream</a> ;
+
+typedef <a href="#z_stream_s">z_stream</a> FAR * <a name="z_streamp">z_streamp</a>;  ÿ
+</pre>
+</font>
+   The application must update <a href="#next_in">next_in</a> and <a href="#avail_in">avail_in</a> when <a href="#avail_in">avail_in</a> has
+   dropped to zero. It must update <a href="#next_out">next_out</a> and <a href="#avail_out">avail_out</a> when <a href="#avail_out">avail_out</a>
+   has dropped to zero. The application must initialize <a href="#zalloc">zalloc</a>, <a href="#zfree">zfree</a> and
+   <a href="#opaque">opaque</a> before calling the init function. All other fields are set by the
+   compression library and must not be updated by the application. <p>
+
+   The <a href="#opaque">opaque</a> value provided by the application will be passed as the first
+   parameter for calls of <a href="#zalloc">zalloc</a> and <a href="#zfree">zfree</a>. This can be useful for custom
+   memory management. The compression library attaches no meaning to the
+   <a href="#opaque">opaque</a> value. <p>
+
+   <a href="#zalloc">zalloc</a> must return <a href="#Z_NULL">Z_NULL</a> if there is not enough memory for the object.
+   If zlib is used in a multi-threaded application, <a href="#zalloc">zalloc</a> and <a href="#zfree">zfree</a> must be
+   thread safe. <p>
+
+   On 16-bit systems, the functions <a href="#zalloc">zalloc</a> and <a href="#zfree">zfree</a> must be able to allocate
+   exactly 65536 bytes, but will not be required to allocate more than this
+   if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
+   pointers returned by <a href="#zalloc">zalloc</a> for objects of exactly 65536 bytes *must*
+   have their offset normalized to zero. The default allocation function
+   provided by this library ensures this (see zutil.c). To reduce memory
+   requirements and avoid any allocation of 64K objects, at the expense of
+   compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
+   <p>
+
+   The fields <a href="#total_in">total_in</a> and <a href="#total_out">total_out</a> can be used for statistics or
+   progress reports. After compression, <a href="#total_in">total_in</a> holds the total size of
+   the uncompressed data and may be saved for use in the decompressor
+   (particularly if the decompressor wants to decompress everything in
+   a single step). <p>
+
+<hr>
+<a name="Constants"><h2> Constants </h2>
+<font color="Blue">
+<pre>
+#define <a name="Z_NO_FLUSH">Z_NO_FLUSH</a>      0
+#define <a name="Z_PARTIAL_FLUSH">Z_PARTIAL_FLUSH</a> 1
+	/* will be removed, use <a href="#Z_SYNC_FLUSH">Z_SYNC_FLUSH</a> instead */
+#define <a name="Z_SYNC_FLUSH">Z_SYNC_FLUSH</a>    2
+#define <a name="Z_FULL_FLUSH">Z_FULL_FLUSH</a>    3
+#define <a name="Z_FINISH">Z_FINISH</a>        4
+/* Allowed flush values ; see <a href="#deflate">deflate</a>() below for details */
+
+#define <a name="Z_OK">Z_OK</a>            0
+#define <a name="Z_STREAM_END">Z_STREAM_END</a>    1
+#define <a name="Z_NEED_DICT">Z_NEED_DICT</a>     2
+#define <a name="Z_ERRNO">Z_ERRNO</a>        (-1)
+#define <a name="Z_STREAM_ERROR">Z_STREAM_ERROR</a> (-2)
+#define <a name="Z_DATA_ERROR">Z_DATA_ERROR</a>   (-3)
+#define <a name="Z_MEM_ERROR">Z_MEM_ERROR</a>    (-4)
+#define <a name="Z_BUF_ERROR">Z_BUF_ERROR</a>    (-5)
+#define <a name="Z_VERSION_ERROR">Z_VERSION_ERROR</a> (-6)
+/* Return codes for the compression/decompression functions. Negative
+ * values are errors, positive values are used for special but normal events.
+ */
+
+#define <a name="Z_NO_COMPRESSION">Z_NO_COMPRESSION</a>         0
+#define <a name="Z_BEST_SPEED">Z_BEST_SPEED</a>             1
+#define <a name="Z_BEST_COMPRESSION">Z_BEST_COMPRESSION</a>       9
+#define <a name="Z_DEFAULT_COMPRESSION">Z_DEFAULT_COMPRESSION</a>  (-1)
+/* compression levels */
+
+#define <a name="Z_FILTERED">Z_FILTERED</a>            1
+#define <a name="Z_HUFFMAN_ONLY">Z_HUFFMAN_ONLY</a>        2
+#define <a name="Z_DEFAULT_STRATEGY">Z_DEFAULT_STRATEGY</a>    0
+/* compression strategy ; see <a href="#deflateInit2">deflateInit2</a>() below for details */
+
+#define <a name="Z_BINARY">Z_BINARY</a>   0
+#define <a name="Z_ASCII">Z_ASCII</a>    1
+#define <a name="Z_UNKNOWN">Z_UNKNOWN</a>  2
+/* Possible values of the <a href="#data_type">data_type</a> field */
+
+#define <a name="Z_DEFLATED">Z_DEFLATED</a>   8
+/* The <a href="#deflate">deflate</a> compression method (the only one supported in this version) */
+
+#define <a name="Z_NULL">Z_NULL</a>  0  /* for initializing <a href="#zalloc">zalloc</a>, <a href="#zfree">zfree</a>, <a href="#opaque">opaque</a> */
+
+#define <a name="zlib_version">zlib_version</a> <a href="#zlibVersion">zlibVersion</a>()
+/* for compatibility with versions less than 1.0.2 */
+</pre>
+</font>
+
+<hr>
+<a name="Misc"><h2> Misc </h2>
+ <a href="#deflateInit">deflateInit</a> and <a href="#inflateInit">inflateInit</a> are macros to allow checking the zlib version
+ and the compiler's view of <a href="#z_stream_s">z_stream</a>.
+ <p>
+ Other functions:
+ <dl>
+ <font color="Blue"><dt> const char   *  <a name="zError">zError</a>           (int err);</font>
+ <font color="Blue"><dt> int             <a name="inflateSyncPoint">inflateSyncPoint</a> (<a href="#z_streamp">z_streamp</a> z);</font>
+ <font color="Blue"><dt> const uLongf *  <a name="get_crc_table">get_crc_table</a>    (void);</font>
+ </dl>
+ <hr>
+ <font size="-1">
+ Last update: Wed Oct 13 20:42:34 1999<br>
+ piapi@csie.ntu.edu.tw
+ </font>
+
+</body>
+</html>
diff --git a/gs/zlib/projects/README.projects b/gs/zlib/projects/README.projects
new file mode 100644
index 000000000..1c029e4a3
--- /dev/null
+++ b/gs/zlib/projects/README.projects
@@ -0,0 +1,41 @@
+This directory contains project files for building zlib under various
+Integrated Development Environments (IDE).
+
+If you wish to submit a new project to this directory, you should comply
+to the following requirements.  Otherwise (e.g. if you wish to integrate
+a custom piece of code that changes the zlib interface or its behavior),
+please consider submitting the project to the contrib directory.
+
+
+Requirements
+============
+
+- The project must build zlib using the source files from the official
+  zlib source distribution, exclusively.
+
+- If the project produces redistributable builds (e.g. shared objects
+  or DLL files), these builds must be compatible to those produced by
+  makefiles, if such makefiles exist in the zlib distribution.
+  In particular, if the project produces a DLL build for the Win32
+  platform, this build must comply to the officially-ammended Win32 DLL
+  Application Binary Interface (ABI), described in win32/DLL_FAQ.txt.
+
+- The project may provide additional build targets, which depend on
+  3rd-party (unofficially-supported) software, present in the contrib
+  directory.  For example, it is possible to provide an "ASM build",
+  besides the officially-supported build, and have ASM source files
+  among its dependencies.
+
+- If there are significant differences between the project files created
+  by different versions of an IDE (e.g. Visual C++ 6.0 vs. 7.0), the name
+  of the project directory should contain the version number of the IDE
+  for which the project is intended (e.g. "visualc6" for Visual C++ 6.0,
+  or "visualc7" for Visual C++ 7.0 and 7.1).
+
+
+Current projects
+================
+
+visualc6/   by Simon-Pierre Cadieux <methodex@methodex.ca>
+            and Cosmin Truta <cosmint@cs.ubbcluj.ro>
+        Project for Microsoft Visual C++ 6.0
diff --git a/gs/zlib/projects/visualc6/README.txt b/gs/zlib/projects/visualc6/README.txt
new file mode 100644
index 000000000..d0296c272
--- /dev/null
+++ b/gs/zlib/projects/visualc6/README.txt
@@ -0,0 +1,73 @@
+Microsoft Developer Studio Project Files, Format Version 6.00 for zlib.

+

+Copyright (C) 2000-2004 Simon-Pierre Cadieux.

+Copyright (C) 2004 Cosmin Truta.

+For conditions of distribution and use, see copyright notice in zlib.h.

+

+

+This project builds the zlib binaries as follows:

+

+* Win32_DLL_Release\zlib1.dll       DLL build

+* Win32_DLL_Debug\zlib1d.dll        DLL build (debug version)

+* Win32_DLL_ASM_Release\zlib1.dll   DLL build using ASM code

+* Win32_DLL_ASM_Debug\zlib1d.dll    DLL build using ASM code (debug version)

+* Win32_LIB_Release\zlib.lib        static build

+* Win32_LIB_Debug\zlibd.lib         static build (debug version)

+* Win32_LIB_ASM_Release\zlib.lib    static build using ASM code

+* Win32_LIB_ASM_Debug\zlibd.lib     static build using ASM code (debug version)

+

+

+For more information regarding the DLL builds, please see the DLL FAQ

+in ..\..\win32\DLL_FAQ.txt.

+

+

+To build and test:

+

+1) On the main menu, select "File | Open Workspace".

+   Open "zlib.dsw".

+

+2) Select "Build | Set Active Configuration".

+   Choose the configuration you wish to build.

+

+3) Select "Build | Clean".

+

+4) Select "Build | Build ... (F7)".  Ignore warning messages about

+   not being able to find certain include files (e.g. alloc.h).

+

+5) If you built one of the sample programs (example or minigzip),

+   select "Build | Execute ... (Ctrl+F5)".

+

+

+To use:

+

+1) Select "Project | Settings (Alt+F7)".

+   Make note of the configuration names used in your project.

+   Usually, these names are "Win32 Release" and "Win32 Debug".

+

+2) In the Workspace window, select the "FileView" tab.

+   Right-click on the root item "Workspace '...'".

+   Select "Insert Project into Workspace".

+   Switch on the checkbox "Dependency of:", and select the name

+   of your project.  Open "zlib.dsp".

+

+3) Select "Build | Configurations".

+   For each configuration of your project:

+   3.1) Choose the zlib configuration you wish to use.

+   3.2) Click on "Add".

+   3.3) Set the new zlib configuration name to the name used by

+        the configuration from the current iteration.

+

+4) Select "Build | Set Active Configuration".

+   Choose the configuration you wish to build.

+

+5) Select "Build | Build ... (F7)".

+

+6) If you built an executable program, select

+   "Build | Execute ... (Ctrl+F5)".

+

+

+Note:

+

+To build the ASM-enabled code, you need Microsoft Assembler

+(ML.EXE).  You can get it by downloading and installing the

+latest Processor Pack for Visual C++ 6.0.

diff --git a/gs/zlib/projects/visualc6/example.dsp b/gs/zlib/projects/visualc6/example.dsp
new file mode 100644
index 000000000..e072a37ff
--- /dev/null
+++ b/gs/zlib/projects/visualc6/example.dsp
@@ -0,0 +1,278 @@
+# Microsoft Developer Studio Project File - Name="example" - Package Owner=<4>

+# Microsoft Developer Studio Generated Build File, Format Version 6.00

+# ** DO NOT EDIT **

+

+# TARGTYPE "Win32 (x86) Console Application" 0x0103

+

+CFG=example - Win32 LIB Debug

+!MESSAGE This is not a valid makefile. To build this project using NMAKE,

+!MESSAGE use the Export Makefile command and run

+!MESSAGE 

+!MESSAGE NMAKE /f "example.mak".

+!MESSAGE 

+!MESSAGE You can specify a configuration when running NMAKE

+!MESSAGE by defining the macro CFG on the command line. For example:

+!MESSAGE 

+!MESSAGE NMAKE /f "example.mak" CFG="example - Win32 LIB Debug"

+!MESSAGE 

+!MESSAGE Possible choices for configuration are:

+!MESSAGE 

+!MESSAGE "example - Win32 DLL Release" (based on "Win32 (x86) Console Application")

+!MESSAGE "example - Win32 DLL Debug" (based on "Win32 (x86) Console Application")

+!MESSAGE "example - Win32 DLL ASM Release" (based on "Win32 (x86) Console Application")

+!MESSAGE "example - Win32 DLL ASM Debug" (based on "Win32 (x86) Console Application")

+!MESSAGE "example - Win32 LIB Release" (based on "Win32 (x86) Console Application")

+!MESSAGE "example - Win32 LIB Debug" (based on "Win32 (x86) Console Application")

+!MESSAGE "example - Win32 LIB ASM Release" (based on "Win32 (x86) Console Application")

+!MESSAGE "example - Win32 LIB ASM Debug" (based on "Win32 (x86) Console Application")

+!MESSAGE 

+

+# Begin Project

+# PROP AllowPerConfigDependencies 0

+# PROP Scc_ProjName ""

+# PROP Scc_LocalPath ""

+CPP=cl.exe

+RSC=rc.exe

+

+!IF  "$(CFG)" == "example - Win32 DLL Release"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 0

+# PROP BASE Output_Dir "example___Win32_DLL_Release"

+# PROP BASE Intermediate_Dir "example___Win32_DLL_Release"

+# PROP BASE Target_Dir ""

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+# PROP Output_Dir "Win32_DLL_Release"

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+# SUBTRACT CPP /YX

+# ADD BASE RSC /l 0x409 /d "NDEBUG"

+# ADD RSC /l 0x409 /d "NDEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /machine:I386

+# ADD LINK32 /nologo /subsystem:console /machine:I386

+

+!ELSEIF  "$(CFG)" == "example - Win32 DLL Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

+# PROP BASE Output_Dir "example___Win32_DLL_Debug"

+# PROP BASE Intermediate_Dir "example___Win32_DLL_Debug"

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+# ADD RSC /l 0x409 /d "_DEBUG"

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+# ADD BSC32 /nologo

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+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+# ADD LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

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+

+# PROP BASE Use_MFC 0

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+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /machine:I386

+# ADD LINK32 /nologo /subsystem:console /machine:I386

+

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+

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+# ADD LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+

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+

+# PROP BASE Use_MFC 0

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+# ADD LINK32 /nologo /subsystem:console /machine:I386

+

+!ELSEIF  "$(CFG)" == "example - Win32 LIB Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

+# PROP BASE Output_Dir "example___Win32_LIB_Debug"

+# PROP BASE Intermediate_Dir "example___Win32_LIB_Debug"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 1

+# PROP Output_Dir "Win32_LIB_Debug"

+# PROP Intermediate_Dir "Win32_LIB_Debug"

+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

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+# ADD RSC /l 0x409 /d "_DEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

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+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+# ADD LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+

+!ELSEIF  "$(CFG)" == "example - Win32 LIB ASM Release"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 0

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+# PROP BASE Intermediate_Dir "example___Win32_LIB_ASM_Release"

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+# ADD RSC /l 0x409 /d "NDEBUG"

+BSC32=bscmake.exe

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+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /machine:I386

+# ADD LINK32 /nologo /subsystem:console /machine:I386

+

+!ELSEIF  "$(CFG)" == "example - Win32 LIB ASM Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

+# PROP BASE Output_Dir "example___Win32_LIB_ASM_Debug"

+# PROP BASE Intermediate_Dir "example___Win32_LIB_ASM_Debug"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 1

+# PROP Output_Dir "Win32_LIB_ASM_Debug"

+# PROP Intermediate_Dir "Win32_LIB_ASM_Debug"

+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

+# SUBTRACT BASE CPP /YX

+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

+# SUBTRACT CPP /YX

+# ADD BASE RSC /l 0x409 /d "_DEBUG"

+# ADD RSC /l 0x409 /d "_DEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+# ADD LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+

+!ENDIF 

+

+# Begin Target

+

+# Name "example - Win32 DLL Release"

+# Name "example - Win32 DLL Debug"

+# Name "example - Win32 DLL ASM Release"

+# Name "example - Win32 DLL ASM Debug"

+# Name "example - Win32 LIB Release"

+# Name "example - Win32 LIB Debug"

+# Name "example - Win32 LIB ASM Release"

+# Name "example - Win32 LIB ASM Debug"

+# Begin Group "Source Files"

+

+# PROP Default_Filter "cpp;c;cxx;rc;def;r;odl;idl;hpj;bat"

+# Begin Source File

+

+SOURCE=..\..\example.c

+# End Source File

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+# PROP Default_Filter "h;hpp;hxx;hm;inl"

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+

+SOURCE=..\..\zconf.h

+# End Source File

+# Begin Source File

+

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+# End Source File

+# End Group

+# End Target

+# End Project

diff --git a/gs/zlib/projects/visualc6/minigzip.dsp b/gs/zlib/projects/visualc6/minigzip.dsp
new file mode 100644
index 000000000..f32024eaf
--- /dev/null
+++ b/gs/zlib/projects/visualc6/minigzip.dsp
@@ -0,0 +1,278 @@
+# Microsoft Developer Studio Project File - Name="minigzip" - Package Owner=<4>

+# Microsoft Developer Studio Generated Build File, Format Version 6.00

+# ** DO NOT EDIT **

+

+# TARGTYPE "Win32 (x86) Console Application" 0x0103

+

+CFG=minigzip - Win32 LIB Debug

+!MESSAGE This is not a valid makefile. To build this project using NMAKE,

+!MESSAGE use the Export Makefile command and run

+!MESSAGE 

+!MESSAGE NMAKE /f "minigzip.mak".

+!MESSAGE 

+!MESSAGE You can specify a configuration when running NMAKE

+!MESSAGE by defining the macro CFG on the command line. For example:

+!MESSAGE 

+!MESSAGE NMAKE /f "minigzip.mak" CFG="minigzip - Win32 LIB Debug"

+!MESSAGE 

+!MESSAGE Possible choices for configuration are:

+!MESSAGE 

+!MESSAGE "minigzip - Win32 DLL Release" (based on "Win32 (x86) Console Application")

+!MESSAGE "minigzip - Win32 DLL Debug" (based on "Win32 (x86) Console Application")

+!MESSAGE "minigzip - Win32 DLL ASM Release" (based on "Win32 (x86) Console Application")

+!MESSAGE "minigzip - Win32 DLL ASM Debug" (based on "Win32 (x86) Console Application")

+!MESSAGE "minigzip - Win32 LIB Release" (based on "Win32 (x86) Console Application")

+!MESSAGE "minigzip - Win32 LIB Debug" (based on "Win32 (x86) Console Application")

+!MESSAGE "minigzip - Win32 LIB ASM Release" (based on "Win32 (x86) Console Application")

+!MESSAGE "minigzip - Win32 LIB ASM Debug" (based on "Win32 (x86) Console Application")

+!MESSAGE 

+

+# Begin Project

+# PROP AllowPerConfigDependencies 0

+# PROP Scc_ProjName ""

+# PROP Scc_LocalPath ""

+CPP=cl.exe

+RSC=rc.exe

+

+!IF  "$(CFG)" == "minigzip - Win32 DLL Release"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 0

+# PROP BASE Output_Dir "minigzip___Win32_DLL_Release"

+# PROP BASE Intermediate_Dir "minigzip___Win32_DLL_Release"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 0

+# PROP Output_Dir "Win32_DLL_Release"

+# PROP Intermediate_Dir "Win32_DLL_Release"

+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT BASE CPP /YX

+# ADD CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT CPP /YX

+# ADD BASE RSC /l 0x409 /d "NDEBUG"

+# ADD RSC /l 0x409 /d "NDEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /machine:I386

+# ADD LINK32 /nologo /subsystem:console /machine:I386

+

+!ELSEIF  "$(CFG)" == "minigzip - Win32 DLL Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

+# PROP BASE Output_Dir "minigzip___Win32_DLL_Debug"

+# PROP BASE Intermediate_Dir "minigzip___Win32_DLL_Debug"

+# PROP BASE Target_Dir ""

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+# PROP Use_Debug_Libraries 1

+# PROP Output_Dir "Win32_DLL_Debug"

+# PROP Intermediate_Dir "Win32_DLL_Debug"

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+# PROP Target_Dir ""

+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

+# SUBTRACT BASE CPP /YX

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+# SUBTRACT CPP /YX

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+# ADD RSC /l 0x409 /d "_DEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

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+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+# ADD LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+

+!ELSEIF  "$(CFG)" == "minigzip - Win32 DLL ASM Release"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 0

+# PROP BASE Output_Dir "minigzip___Win32_DLL_ASM_Release"

+# PROP BASE Intermediate_Dir "minigzip___Win32_DLL_ASM_Release"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 0

+# PROP Output_Dir "Win32_DLL_ASM_Release"

+# PROP Intermediate_Dir "Win32_DLL_ASM_Release"

+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT BASE CPP /YX

+# ADD CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT CPP /YX

+# ADD BASE RSC /l 0x409 /d "NDEBUG"

+# ADD RSC /l 0x409 /d "NDEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /machine:I386

+# ADD LINK32 /nologo /subsystem:console /machine:I386

+

+!ELSEIF  "$(CFG)" == "minigzip - Win32 DLL ASM Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

+# PROP BASE Output_Dir "minigzip___Win32_DLL_ASM_Debug"

+# PROP BASE Intermediate_Dir "minigzip___Win32_DLL_ASM_Debug"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 1

+# PROP Output_Dir "Win32_DLL_ASM_Debug"

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+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

+# SUBTRACT BASE CPP /YX

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+# SUBTRACT CPP /YX

+# ADD BASE RSC /l 0x409 /d "_DEBUG"

+# ADD RSC /l 0x409 /d "_DEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+# ADD LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+

+!ELSEIF  "$(CFG)" == "minigzip - Win32 LIB Release"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 0

+# PROP BASE Output_Dir "minigzip___Win32_LIB_Release"

+# PROP BASE Intermediate_Dir "minigzip___Win32_LIB_Release"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

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+# PROP Ignore_Export_Lib 0

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+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT BASE CPP /YX

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+# SUBTRACT CPP /YX

+# ADD BASE RSC /l 0x409 /d "NDEBUG"

+# ADD RSC /l 0x409 /d "NDEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /machine:I386

+# ADD LINK32 /nologo /subsystem:console /machine:I386

+

+!ELSEIF  "$(CFG)" == "minigzip - Win32 LIB Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

+# PROP BASE Output_Dir "minigzip___Win32_LIB_Debug"

+# PROP BASE Intermediate_Dir "minigzip___Win32_LIB_Debug"

+# PROP BASE Target_Dir ""

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+# PROP Use_Debug_Libraries 1

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+# PROP Intermediate_Dir "Win32_LIB_Debug"

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+# PROP Target_Dir ""

+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

+# SUBTRACT BASE CPP /YX

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+# SUBTRACT CPP /YX

+# ADD BASE RSC /l 0x409 /d "_DEBUG"

+# ADD RSC /l 0x409 /d "_DEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

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+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+# ADD LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+

+!ELSEIF  "$(CFG)" == "minigzip - Win32 LIB ASM Release"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 0

+# PROP BASE Output_Dir "minigzip___Win32_LIB_ASM_Release"

+# PROP BASE Intermediate_Dir "minigzip___Win32_LIB_ASM_Release"

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+# PROP Use_MFC 0

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+# PROP Intermediate_Dir "Win32_LIB_ASM_Release"

+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT BASE CPP /YX

+# ADD CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT CPP /YX

+# ADD BASE RSC /l 0x409 /d "NDEBUG"

+# ADD RSC /l 0x409 /d "NDEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /machine:I386

+# ADD LINK32 /nologo /subsystem:console /machine:I386

+

+!ELSEIF  "$(CFG)" == "minigzip - Win32 LIB ASM Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

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+# PROP BASE Intermediate_Dir "minigzip___Win32_LIB_ASM_Debug"

+# PROP BASE Target_Dir ""

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+# PROP Intermediate_Dir "Win32_LIB_ASM_Debug"

+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

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+# ADD BASE RSC /l 0x409 /d "_DEBUG"

+# ADD RSC /l 0x409 /d "_DEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+# ADD LINK32 /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept

+

+!ENDIF 

+

+# Begin Target

+

+# Name "minigzip - Win32 DLL Release"

+# Name "minigzip - Win32 DLL Debug"

+# Name "minigzip - Win32 DLL ASM Release"

+# Name "minigzip - Win32 DLL ASM Debug"

+# Name "minigzip - Win32 LIB Release"

+# Name "minigzip - Win32 LIB Debug"

+# Name "minigzip - Win32 LIB ASM Release"

+# Name "minigzip - Win32 LIB ASM Debug"

+# Begin Group "Source Files"

+

+# PROP Default_Filter "cpp;c;cxx;rc;def;r;odl;idl;hpj;bat"

+# Begin Source File

+

+SOURCE=..\..\minigzip.c

+# End Source File

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+

+# PROP Default_Filter "h;hpp;hxx;hm;inl"

+# Begin Source File

+

+SOURCE=..\..\zconf.h

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\zlib.h

+# End Source File

+# End Group

+# End Target

+# End Project

diff --git a/gs/zlib/projects/visualc6/zlib.dsp b/gs/zlib/projects/visualc6/zlib.dsp
new file mode 100644
index 000000000..0fe0604cc
--- /dev/null
+++ b/gs/zlib/projects/visualc6/zlib.dsp
@@ -0,0 +1,609 @@
+# Microsoft Developer Studio Project File - Name="zlib" - Package Owner=<4>

+# Microsoft Developer Studio Generated Build File, Format Version 6.00

+# ** DO NOT EDIT **

+

+# TARGTYPE "Win32 (x86) Dynamic-Link Library" 0x0102

+# TARGTYPE "Win32 (x86) Static Library" 0x0104

+

+CFG=zlib - Win32 LIB Debug

+!MESSAGE This is not a valid makefile. To build this project using NMAKE,

+!MESSAGE use the Export Makefile command and run

+!MESSAGE 

+!MESSAGE NMAKE /f "zlib.mak".

+!MESSAGE 

+!MESSAGE You can specify a configuration when running NMAKE

+!MESSAGE by defining the macro CFG on the command line. For example:

+!MESSAGE 

+!MESSAGE NMAKE /f "zlib.mak" CFG="zlib - Win32 LIB Debug"

+!MESSAGE 

+!MESSAGE Possible choices for configuration are:

+!MESSAGE 

+!MESSAGE "zlib - Win32 DLL Release" (based on "Win32 (x86) Dynamic-Link Library")

+!MESSAGE "zlib - Win32 DLL Debug" (based on "Win32 (x86) Dynamic-Link Library")

+!MESSAGE "zlib - Win32 DLL ASM Release" (based on "Win32 (x86) Dynamic-Link Library")

+!MESSAGE "zlib - Win32 DLL ASM Debug" (based on "Win32 (x86) Dynamic-Link Library")

+!MESSAGE "zlib - Win32 LIB Release" (based on "Win32 (x86) Static Library")

+!MESSAGE "zlib - Win32 LIB Debug" (based on "Win32 (x86) Static Library")

+!MESSAGE "zlib - Win32 LIB ASM Release" (based on "Win32 (x86) Static Library")

+!MESSAGE "zlib - Win32 LIB ASM Debug" (based on "Win32 (x86) Static Library")

+!MESSAGE 

+

+# Begin Project

+# PROP AllowPerConfigDependencies 0

+# PROP Scc_ProjName ""

+# PROP Scc_LocalPath ""

+

+!IF  "$(CFG)" == "zlib - Win32 DLL Release"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 0

+# PROP BASE Output_Dir "zlib___Win32_DLL_Release"

+# PROP BASE Intermediate_Dir "zlib___Win32_DLL_Release"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 0

+# PROP Output_Dir "Win32_DLL_Release"

+# PROP Intermediate_Dir "Win32_DLL_Release"

+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+CPP=cl.exe

+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT BASE CPP /YX /Yc /Yu

+# ADD CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT CPP /YX /Yc /Yu

+MTL=midl.exe

+# ADD BASE MTL /nologo /D "NDEBUG" /mktyplib203 /win32

+# ADD MTL /nologo /D "NDEBUG" /mktyplib203 /win32

+RSC=rc.exe

+# ADD BASE RSC /l 0x409 /d "NDEBUG"

+# ADD RSC /l 0x409 /d "NDEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /dll /machine:I386

+# ADD LINK32 /nologo /dll /machine:I386 /out:"Win32_DLL_Release\zlib1.dll"

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

+# PROP BASE Output_Dir "zlib___Win32_DLL_Debug"

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+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

+# SUBTRACT BASE CPP /YX /Yc /Yu

+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

+# SUBTRACT CPP /YX /Yc /Yu

+MTL=midl.exe

+# ADD BASE MTL /nologo /D "_DEBUG" /mktyplib203 /win32

+# ADD MTL /nologo /D "_DEBUG" /mktyplib203 /win32

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+# ADD BASE RSC /l 0x409 /d "_DEBUG"

+# ADD RSC /l 0x409 /d "_DEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /dll /debug /machine:I386 /pdbtype:sept

+# ADD LINK32 /nologo /dll /debug /machine:I386 /out:"Win32_DLL_Debug\zlib1d.dll" /pdbtype:sept

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL ASM Release"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 0

+# PROP BASE Output_Dir "zlib___Win32_DLL_ASM_Release"

+# PROP BASE Intermediate_Dir "zlib___Win32_DLL_ASM_Release"

+# PROP BASE Target_Dir ""

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+# PROP Output_Dir "Win32_DLL_ASM_Release"

+# PROP Intermediate_Dir "Win32_DLL_ASM_Release"

+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+CPP=cl.exe

+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT BASE CPP /YX /Yc /Yu

+# ADD CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /D "ASMV" /D "ASMINF" /FD /c

+# SUBTRACT CPP /YX /Yc /Yu

+MTL=midl.exe

+# ADD BASE MTL /nologo /D "NDEBUG" /mktyplib203 /win32

+# ADD MTL /nologo /D "NDEBUG" /mktyplib203 /win32

+RSC=rc.exe

+# ADD BASE RSC /l 0x409 /d "NDEBUG"

+# ADD RSC /l 0x409 /d "NDEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /dll /machine:I386

+# ADD LINK32 /nologo /dll /machine:I386 /out:"Win32_DLL_ASM_Release\zlib1.dll"

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL ASM Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

+# PROP BASE Output_Dir "zlib___Win32_DLL_ASM_Debug"

+# PROP BASE Intermediate_Dir "zlib___Win32_DLL_ASM_Debug"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 1

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+# PROP Intermediate_Dir "Win32_DLL_ASM_Debug"

+# PROP Ignore_Export_Lib 0

+# PROP Target_Dir ""

+CPP=cl.exe

+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

+# SUBTRACT BASE CPP /YX /Yc /Yu

+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /D "ASMV" /D "ASMINF" /FD /GZ /c

+# SUBTRACT CPP /YX /Yc /Yu

+MTL=midl.exe

+# ADD BASE MTL /nologo /D "_DEBUG" /mktyplib203 /win32

+# ADD MTL /nologo /D "_DEBUG" /mktyplib203 /win32

+RSC=rc.exe

+# ADD BASE RSC /l 0x409 /d "_DEBUG"

+# ADD RSC /l 0x409 /d "_DEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LINK32=link.exe

+# ADD BASE LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /dll /debug /machine:I386 /pdbtype:sept

+# ADD LINK32 /nologo /dll /debug /machine:I386 /out:"Win32_DLL_ASM_Debug\zlib1d.dll" /pdbtype:sept

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB Release"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 0

+# PROP BASE Output_Dir "zlib___Win32_LIB_Release"

+# PROP BASE Intermediate_Dir "zlib___Win32_LIB_Release"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 0

+# PROP Output_Dir "Win32_LIB_Release"

+# PROP Intermediate_Dir "Win32_LIB_Release"

+# PROP Target_Dir ""

+CPP=cl.exe

+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT BASE CPP /YX /Yc /Yu

+# ADD CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT CPP /YX /Yc /Yu

+RSC=rc.exe

+# ADD BASE RSC /l 0x409 /d "NDEBUG"

+# ADD RSC /l 0x409 /d "NDEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LIB32=link.exe -lib

+# ADD BASE LIB32 /nologo

+# ADD LIB32 /nologo

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

+# PROP BASE Output_Dir "zlib___Win32_LIB_Debug"

+# PROP BASE Intermediate_Dir "zlib___Win32_LIB_Debug"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 1

+# PROP Output_Dir "Win32_LIB_Debug"

+# PROP Intermediate_Dir "Win32_LIB_Debug"

+# PROP Target_Dir ""

+CPP=cl.exe

+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

+# SUBTRACT BASE CPP /YX /Yc /Yu

+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

+# SUBTRACT CPP /YX /Yc /Yu

+RSC=rc.exe

+# ADD BASE RSC /l 0x409 /d "_DEBUG"

+# ADD RSC /l 0x409 /d "_DEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LIB32=link.exe -lib

+# ADD BASE LIB32 /nologo

+# ADD LIB32 /nologo /out:"Win32_LIB_Debug\zlibd.lib"

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB ASM Release"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 0

+# PROP BASE Output_Dir "zlib___Win32_LIB_ASM_Release"

+# PROP BASE Intermediate_Dir "zlib___Win32_LIB_ASM_Release"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 0

+# PROP Output_Dir "Win32_LIB_ASM_Release"

+# PROP Intermediate_Dir "Win32_LIB_ASM_Release"

+# PROP Target_Dir ""

+CPP=cl.exe

+# ADD BASE CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /FD /c

+# SUBTRACT BASE CPP /YX /Yc /Yu

+# ADD CPP /nologo /MD /W3 /O2 /D "WIN32" /D "NDEBUG" /D "ASMV" /D "ASMINF" /FD /c

+# SUBTRACT CPP /YX /Yc /Yu

+RSC=rc.exe

+# ADD BASE RSC /l 0x409 /d "NDEBUG"

+# ADD RSC /l 0x409 /d "NDEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LIB32=link.exe -lib

+# ADD BASE LIB32 /nologo

+# ADD LIB32 /nologo

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB ASM Debug"

+

+# PROP BASE Use_MFC 0

+# PROP BASE Use_Debug_Libraries 1

+# PROP BASE Output_Dir "zlib___Win32_LIB_ASM_Debug"

+# PROP BASE Intermediate_Dir "zlib___Win32_LIB_ASM_Debug"

+# PROP BASE Target_Dir ""

+# PROP Use_MFC 0

+# PROP Use_Debug_Libraries 1

+# PROP Output_Dir "Win32_LIB_ASM_Debug"

+# PROP Intermediate_Dir "Win32_LIB_ASM_Debug"

+# PROP Target_Dir ""

+CPP=cl.exe

+# ADD BASE CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /FD /GZ /c

+# SUBTRACT BASE CPP /YX /Yc /Yu

+# ADD CPP /nologo /MDd /W3 /Gm /ZI /Od /D "WIN32" /D "_DEBUG" /D "ASMV" /D "ASMINF" /FD /GZ /c

+# SUBTRACT CPP /YX /Yc /Yu

+RSC=rc.exe

+# ADD BASE RSC /l 0x409 /d "_DEBUG"

+# ADD RSC /l 0x409 /d "_DEBUG"

+BSC32=bscmake.exe

+# ADD BASE BSC32 /nologo

+# ADD BSC32 /nologo

+LIB32=link.exe -lib

+# ADD BASE LIB32 /nologo

+# ADD LIB32 /nologo /out:"Win32_LIB_ASM_Debug\zlibd.lib"

+

+!ENDIF 

+

+# Begin Target

+

+# Name "zlib - Win32 DLL Release"

+# Name "zlib - Win32 DLL Debug"

+# Name "zlib - Win32 DLL ASM Release"

+# Name "zlib - Win32 DLL ASM Debug"

+# Name "zlib - Win32 LIB Release"

+# Name "zlib - Win32 LIB Debug"

+# Name "zlib - Win32 LIB ASM Release"

+# Name "zlib - Win32 LIB ASM Debug"

+# Begin Group "Source Files"

+

+# PROP Default_Filter "cpp;c;cxx;rc;def;r;odl;idl;hpj;bat"

+# Begin Source File

+

+SOURCE=..\..\adler32.c

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\compress.c

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\crc32.c

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\deflate.c

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\gzio.c

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\infback.c

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\inffast.c

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\inflate.c

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\inftrees.c

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\trees.c

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\uncompr.c

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\win32\zlib.def

+

+!IF  "$(CFG)" == "zlib - Win32 DLL Release"

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL Debug"

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL ASM Release"

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL ASM Debug"

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB Release"

+

+# PROP Exclude_From_Build 1

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB Debug"

+

+# PROP Exclude_From_Build 1

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB ASM Release"

+

+# PROP Exclude_From_Build 1

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB ASM Debug"

+

+# PROP Exclude_From_Build 1

+

+!ENDIF 

+

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\zutil.c

+# End Source File

+# End Group

+# Begin Group "Header Files"

+

+# PROP Default_Filter "h;hpp;hxx;hm;inl"

+# Begin Source File

+

+SOURCE=..\..\crc32.h

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\deflate.h

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\inffast.h

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\inffixed.h

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\inflate.h

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\inftrees.h

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\trees.h

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\zconf.h

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\zlib.h

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\zutil.h

+# End Source File

+# End Group

+# Begin Group "Resource Files"

+

+# PROP Default_Filter "ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe"

+# Begin Source File

+

+SOURCE=..\..\win32\zlib1.rc

+# End Source File

+# End Group

+# Begin Group "Assembler Files (Unsupported)"

+

+# PROP Default_Filter "asm;obj;c;cpp;cxx;h;hpp;hxx"

+# Begin Source File

+

+SOURCE=..\..\contrib\masmx86\gvmat32.asm

+

+!IF  "$(CFG)" == "zlib - Win32 DLL Release"

+

+# PROP Exclude_From_Build 1

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL Debug"

+

+# PROP Exclude_From_Build 1

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL ASM Release"

+

+# Begin Custom Build - Assembling...

+IntDir=.\Win32_DLL_ASM_Release

+InputPath=..\..\contrib\masmx86\gvmat32.asm

+InputName=gvmat32

+

+"$(IntDir)\$(InputName).obj" : $(SOURCE) "$(INTDIR)" "$(OUTDIR)"

+	ml.exe /nologo /c /coff /Cx /Fo"$(IntDir)\$(InputName).obj" "$(InputPath)"

+

+# End Custom Build

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL ASM Debug"

+

+# Begin Custom Build - Assembling...

+IntDir=.\Win32_DLL_ASM_Debug

+InputPath=..\..\contrib\masmx86\gvmat32.asm

+InputName=gvmat32

+

+"$(IntDir)\$(InputName).obj" : $(SOURCE) "$(INTDIR)" "$(OUTDIR)"

+	ml.exe /nologo /c /coff /Cx /Zi /Fo"$(IntDir)\$(InputName).obj" "$(InputPath)"

+

+# End Custom Build

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB Release"

+

+# PROP Exclude_From_Build 1

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB Debug"

+

+# PROP Exclude_From_Build 1

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB ASM Release"

+

+# Begin Custom Build - Assembling...

+IntDir=.\Win32_LIB_ASM_Release

+InputPath=..\..\contrib\masmx86\gvmat32.asm

+InputName=gvmat32

+

+"$(IntDir)\$(InputName).obj" : $(SOURCE) "$(INTDIR)" "$(OUTDIR)"

+	ml.exe /nologo /c /coff /Cx /Fo"$(IntDir)\$(InputName).obj" "$(InputPath)"

+

+# End Custom Build

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB ASM Debug"

+

+# Begin Custom Build - Assembling...

+IntDir=.\Win32_LIB_ASM_Debug

+InputPath=..\..\contrib\masmx86\gvmat32.asm

+InputName=gvmat32

+

+"$(IntDir)\$(InputName).obj" : $(SOURCE) "$(INTDIR)" "$(OUTDIR)"

+	ml.exe /nologo /c /coff /Cx /Zi /Fo"$(IntDir)\$(InputName).obj" "$(InputPath)"

+

+# End Custom Build

+

+!ENDIF 

+

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\contrib\masmx86\gvmat32c.c

+

+!IF  "$(CFG)" == "zlib - Win32 DLL Release"

+

+# PROP Exclude_From_Build 1

+# ADD CPP /I "..\.."

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL Debug"

+

+# PROP Exclude_From_Build 1

+# ADD CPP /I "..\.."

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL ASM Release"

+

+# ADD CPP /I "..\.."

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL ASM Debug"

+

+# ADD CPP /I "..\.."

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB Release"

+

+# PROP Exclude_From_Build 1

+# ADD CPP /I "..\.."

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB Debug"

+

+# PROP Exclude_From_Build 1

+# ADD CPP /I "..\.."

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB ASM Release"

+

+# ADD CPP /I "..\.."

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB ASM Debug"

+

+# ADD CPP /I "..\.."

+

+!ENDIF 

+

+# End Source File

+# Begin Source File

+

+SOURCE=..\..\contrib\masmx86\inffas32.asm

+

+!IF  "$(CFG)" == "zlib - Win32 DLL Release"

+

+# PROP Exclude_From_Build 1

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL Debug"

+

+# PROP Exclude_From_Build 1

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL ASM Release"

+

+# Begin Custom Build - Assembling...

+IntDir=.\Win32_DLL_ASM_Release

+InputPath=..\..\contrib\masmx86\inffas32.asm

+InputName=inffas32

+

+"$(IntDir)\$(InputName).obj" : $(SOURCE) "$(INTDIR)" "$(OUTDIR)"

+	ml.exe /nologo /c /coff /Cx /Fo"$(IntDir)\$(InputName).obj" "$(InputPath)"

+

+# End Custom Build

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 DLL ASM Debug"

+

+# Begin Custom Build - Assembling...

+IntDir=.\Win32_DLL_ASM_Debug

+InputPath=..\..\contrib\masmx86\inffas32.asm

+InputName=inffas32

+

+"$(IntDir)\$(InputName).obj" : $(SOURCE) "$(INTDIR)" "$(OUTDIR)"

+	ml.exe /nologo /c /coff /Cx /Zi /Fo"$(IntDir)\$(InputName).obj" "$(InputPath)"

+

+# End Custom Build

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB Release"

+

+# PROP Exclude_From_Build 1

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB Debug"

+

+# PROP Exclude_From_Build 1

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB ASM Release"

+

+# Begin Custom Build - Assembling...

+IntDir=.\Win32_LIB_ASM_Release

+InputPath=..\..\contrib\masmx86\inffas32.asm

+InputName=inffas32

+

+"$(IntDir)\$(InputName).obj" : $(SOURCE) "$(INTDIR)" "$(OUTDIR)"

+	ml.exe /nologo /c /coff /Cx /Fo"$(IntDir)\$(InputName).obj" "$(InputPath)"

+

+# End Custom Build

+

+!ELSEIF  "$(CFG)" == "zlib - Win32 LIB ASM Debug"

+

+# Begin Custom Build - Assembling...

+IntDir=.\Win32_LIB_ASM_Debug

+InputPath=..\..\contrib\masmx86\inffas32.asm

+InputName=inffas32

+

+"$(IntDir)\$(InputName).obj" : $(SOURCE) "$(INTDIR)" "$(OUTDIR)"

+	ml.exe /nologo /c /coff /Cx /Zi /Fo"$(IntDir)\$(InputName).obj" "$(InputPath)"

+

+# End Custom Build

+

+!ENDIF 

+

+# End Source File

+# End Group

+# Begin Source File

+

+SOURCE=.\README.txt

+# End Source File

+# End Target

+# End Project

diff --git a/gs/zlib/projects/visualc6/zlib.dsw b/gs/zlib/projects/visualc6/zlib.dsw
new file mode 100644
index 000000000..3a771fce0
--- /dev/null
+++ b/gs/zlib/projects/visualc6/zlib.dsw
@@ -0,0 +1,59 @@
+Microsoft Developer Studio Workspace File, Format Version 6.00

+# WARNING: DO NOT EDIT OR DELETE THIS WORKSPACE FILE!

+

+###############################################################################

+

+Project: "example"=.\example.dsp - Package Owner=<4>

+

+Package=<5>

+{{{

+}}}

+

+Package=<4>

+{{{

+    Begin Project Dependency

+    Project_Dep_Name zlib

+    End Project Dependency

+}}}

+

+###############################################################################

+

+Project: "minigzip"=.\minigzip.dsp - Package Owner=<4>

+

+Package=<5>

+{{{

+}}}

+

+Package=<4>

+{{{

+    Begin Project Dependency

+    Project_Dep_Name zlib

+    End Project Dependency

+}}}

+

+###############################################################################

+

+Project: "zlib"=.\zlib.dsp - Package Owner=<4>

+

+Package=<5>

+{{{

+}}}

+

+Package=<4>

+{{{

+}}}

+

+###############################################################################

+

+Global:

+

+Package=<5>

+{{{

+}}}

+

+Package=<3>

+{{{

+}}}

+

+###############################################################################

+

diff --git a/gs/zlib/qnx/package.qpg b/gs/zlib/qnx/package.qpg
new file mode 100644
index 000000000..8a4a47c72
--- /dev/null
+++ b/gs/zlib/qnx/package.qpg
@@ -0,0 +1,141 @@
+<QPG:Generation>
+   <QPG:Options>
+      <QPG:User unattended="no" verbosity="2" listfiles="yes"/>
+      <QPG:Defaults type="qnx_package"/>
+      <QPG:Source></QPG:Source>
+      <QPG:Release number="+"/>
+      <QPG:Build></QPG:Build>
+      <QPG:FileSorting strip="yes"/>
+      <QPG:Package targets="combine"/>
+      <QPG:Repository generate="yes"/>
+      <QPG:FinalDir></QPG:FinalDir>
+      <QPG:Cleanup></QPG:Cleanup>
+   </QPG:Options>
+
+   <QPG:Responsible>
+      <QPG:Company></QPG:Company>
+      <QPG:Department></QPG:Department>
+      <QPG:Group></QPG:Group>
+      <QPG:Team></QPG:Team>
+      <QPG:Employee></QPG:Employee>
+      <QPG:EmailAddress></QPG:EmailAddress>
+   </QPG:Responsible>
+
+   <QPG:Values>
+      <QPG:Files>
+         <QPG:Add file="../zconf.h" install="/opt/include/" user="root:sys" permission="644"/>
+         <QPG:Add file="../zlib.h" install="/opt/include/" user="root:sys" permission="644"/>
+         <QPG:Add file="../libz.so.1.2.3" install="/opt/lib/" user="root:bin" permission="644"/>
+         <QPG:Add file="libz.so" install="/opt/lib/" component="dev" filetype="symlink" linkto="libz.so.1.2.3"/>
+         <QPG:Add file="libz.so.1" install="/opt/lib/" filetype="symlink" linkto="libz.so.1.2.3"/>
+         <QPG:Add file="../libz.so.1.2.3" install="/opt/lib/" component="slib"/>
+      </QPG:Files>
+
+      <QPG:PackageFilter>
+         <QPM:PackageManifest>
+            <QPM:PackageDescription>
+               <QPM:PackageType>Library</QPM:PackageType>
+               <QPM:PackageReleaseNotes></QPM:PackageReleaseNotes>
+               <QPM:PackageReleaseUrgency>Medium</QPM:PackageReleaseUrgency>
+               <QPM:PackageRepository></QPM:PackageRepository>
+               <QPM:FileVersion>2.0</QPM:FileVersion>
+            </QPM:PackageDescription>
+
+            <QPM:ProductDescription>
+               <QPM:ProductName>zlib</QPM:ProductName>
+               <QPM:ProductIdentifier>zlib</QPM:ProductIdentifier>
+               <QPM:ProductEmail>alain.bonnefoy@icbt.com</QPM:ProductEmail>
+               <QPM:VendorName>Public</QPM:VendorName>
+               <QPM:VendorInstallName>public</QPM:VendorInstallName>
+               <QPM:VendorURL>www.gzip.org/zlib</QPM:VendorURL>
+               <QPM:VendorEmbedURL></QPM:VendorEmbedURL>
+               <QPM:VendorEmail></QPM:VendorEmail>
+               <QPM:AuthorName>Jean-Loup Gailly,Mark Adler</QPM:AuthorName>
+               <QPM:AuthorURL>www.gzip.org/zlib</QPM:AuthorURL>
+               <QPM:AuthorEmbedURL></QPM:AuthorEmbedURL>
+               <QPM:AuthorEmail>zlib@gzip.org</QPM:AuthorEmail>
+               <QPM:ProductIconSmall></QPM:ProductIconSmall>
+               <QPM:ProductIconLarge></QPM:ProductIconLarge>
+               <QPM:ProductDescriptionShort>A massively spiffy yet delicately unobtrusive compression library.</QPM:ProductDescriptionShort>
+               <QPM:ProductDescriptionLong>zlib is designed to be a free, general-purpose, legally unencumbered, lossless data compression library for use on virtually any computer hardware and operating system.</QPM:ProductDescriptionLong>
+               <QPM:ProductDescriptionURL>http://www.gzip.org/zlib</QPM:ProductDescriptionURL>
+               <QPM:ProductDescriptionEmbedURL></QPM:ProductDescriptionEmbedURL>
+            </QPM:ProductDescription>
+
+            <QPM:ReleaseDescription>
+               <QPM:ReleaseVersion>1.2.3</QPM:ReleaseVersion>
+               <QPM:ReleaseUrgency>Medium</QPM:ReleaseUrgency>
+               <QPM:ReleaseStability>Stable</QPM:ReleaseStability>
+               <QPM:ReleaseNoteMinor></QPM:ReleaseNoteMinor>
+               <QPM:ReleaseNoteMajor></QPM:ReleaseNoteMajor>
+               <QPM:ExcludeCountries>
+                  <QPM:Country></QPM:Country>
+               </QPM:ExcludeCountries>
+
+               <QPM:ReleaseCopyright>No License</QPM:ReleaseCopyright>
+            </QPM:ReleaseDescription>
+
+            <QPM:ContentDescription>
+               <QPM:ContentTopic xmlmultiple="true">Software Development/Libraries and Extensions/C Libraries</QPM:ContentTopic>
+               <QPM:ContentKeyword>zlib,compression</QPM:ContentKeyword>
+               <QPM:TargetOS>qnx6</QPM:TargetOS>
+               <QPM:HostOS>qnx6</QPM:HostOS>
+               <QPM:DisplayEnvironment xmlmultiple="true">None</QPM:DisplayEnvironment>
+               <QPM:TargetAudience xmlmultiple="true">Developer</QPM:TargetAudience>
+            </QPM:ContentDescription>
+         </QPM:PackageManifest>
+      </QPG:PackageFilter>
+
+      <QPG:PackageFilter proc="none" target="none">
+         <QPM:PackageManifest>
+            <QPM:ProductInstallationDependencies>
+               <QPM:ProductRequirements></QPM:ProductRequirements>
+            </QPM:ProductInstallationDependencies>
+
+            <QPM:ProductInstallationProcedure>
+               <QPM:Script xmlmultiple="true">
+                  <QPM:ScriptName></QPM:ScriptName>
+                  <QPM:ScriptType>Install</QPM:ScriptType>
+                  <QPM:ScriptTiming>Post</QPM:ScriptTiming>
+                  <QPM:ScriptBlocking>No</QPM:ScriptBlocking>
+                  <QPM:ScriptResult>Ignore</QPM:ScriptResult>
+                  <QPM:ShortDescription></QPM:ShortDescription>
+                  <QPM:UseBinaries>No</QPM:UseBinaries>
+                  <QPM:Priority>Optional</QPM:Priority>
+               </QPM:Script>
+            </QPM:ProductInstallationProcedure>
+         </QPM:PackageManifest>
+
+         <QPM:Launch>
+         </QPM:Launch>
+      </QPG:PackageFilter>
+
+      <QPG:PackageFilter type="core" component="none">
+         <QPM:PackageManifest>
+            <QPM:ProductInstallationProcedure>
+	       <QPM:OrderDependency xmlmultiple="true">
+	          <QPM:Order>InstallOver</QPM:Order>
+	          <QPM:Product>zlib</QPM:Product>
+	       </QPM:OrderDependency>
+            </QPM:ProductInstallationProcedure>
+         </QPM:PackageManifest>
+
+         <QPM:Launch>
+         </QPM:Launch>
+      </QPG:PackageFilter>
+
+      <QPG:PackageFilter type="core" component="dev">
+         <QPM:PackageManifest>
+            <QPM:ProductInstallationProcedure>
+	       <QPM:OrderDependency xmlmultiple="true">
+	          <QPM:Order>InstallOver</QPM:Order>
+	          <QPM:Product>zlib-dev</QPM:Product>
+	       </QPM:OrderDependency>
+            </QPM:ProductInstallationProcedure>
+         </QPM:PackageManifest>
+
+         <QPM:Launch>
+         </QPM:Launch>
+      </QPG:PackageFilter>
+   </QPG:Values>
+</QPG:Generation>
diff --git a/gs/zlib/trees.c b/gs/zlib/trees.c
new file mode 100644
index 000000000..395e4e168
--- /dev/null
+++ b/gs/zlib/trees.c
@@ -0,0 +1,1219 @@
+/* trees.c -- output deflated data using Huffman coding
+ * Copyright (C) 1995-2005 Jean-loup Gailly
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/*
+ *  ALGORITHM
+ *
+ *      The "deflation" process uses several Huffman trees. The more
+ *      common source values are represented by shorter bit sequences.
+ *
+ *      Each code tree is stored in a compressed form which is itself
+ * a Huffman encoding of the lengths of all the code strings (in
+ * ascending order by source values).  The actual code strings are
+ * reconstructed from the lengths in the inflate process, as described
+ * in the deflate specification.
+ *
+ *  REFERENCES
+ *
+ *      Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
+ *      Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
+ *
+ *      Storer, James A.
+ *          Data Compression:  Methods and Theory, pp. 49-50.
+ *          Computer Science Press, 1988.  ISBN 0-7167-8156-5.
+ *
+ *      Sedgewick, R.
+ *          Algorithms, p290.
+ *          Addison-Wesley, 1983. ISBN 0-201-06672-6.
+ */
+
+/* @(#) $Id$ */
+
+/* #define GEN_TREES_H */
+
+#include "deflate.h"
+
+#ifdef DEBUG
+#  include <ctype.h>
+#endif
+
+/* ===========================================================================
+ * Constants
+ */
+
+#define MAX_BL_BITS 7
+/* Bit length codes must not exceed MAX_BL_BITS bits */
+
+#define END_BLOCK 256
+/* end of block literal code */
+
+#define REP_3_6      16
+/* repeat previous bit length 3-6 times (2 bits of repeat count) */
+
+#define REPZ_3_10    17
+/* repeat a zero length 3-10 times  (3 bits of repeat count) */
+
+#define REPZ_11_138  18
+/* repeat a zero length 11-138 times  (7 bits of repeat count) */
+
+local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
+   = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0};
+
+local const int extra_dbits[D_CODES] /* extra bits for each distance code */
+   = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
+
+local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */
+   = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
+
+local const uch bl_order[BL_CODES]
+   = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
+/* The lengths of the bit length codes are sent in order of decreasing
+ * probability, to avoid transmitting the lengths for unused bit length codes.
+ */
+
+#define Buf_size (8 * 2*sizeof(char))
+/* Number of bits used within bi_buf. (bi_buf might be implemented on
+ * more than 16 bits on some systems.)
+ */
+
+/* ===========================================================================
+ * Local data. These are initialized only once.
+ */
+
+#define DIST_CODE_LEN  512 /* see definition of array dist_code below */
+
+#if defined(GEN_TREES_H) || !defined(STDC)
+/* non ANSI compilers may not accept trees.h */
+
+local ct_data static_ltree[L_CODES+2];
+/* The static literal tree. Since the bit lengths are imposed, there is no
+ * need for the L_CODES extra codes used during heap construction. However
+ * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
+ * below).
+ */
+
+local ct_data static_dtree[D_CODES];
+/* The static distance tree. (Actually a trivial tree since all codes use
+ * 5 bits.)
+ */
+
+uch _dist_code[DIST_CODE_LEN];
+/* Distance codes. The first 256 values correspond to the distances
+ * 3 .. 258, the last 256 values correspond to the top 8 bits of
+ * the 15 bit distances.
+ */
+
+uch _length_code[MAX_MATCH-MIN_MATCH+1];
+/* length code for each normalized match length (0 == MIN_MATCH) */
+
+local int base_length[LENGTH_CODES];
+/* First normalized length for each code (0 = MIN_MATCH) */
+
+local int base_dist[D_CODES];
+/* First normalized distance for each code (0 = distance of 1) */
+
+#else
+#  include "trees.h"
+#endif /* GEN_TREES_H */
+
+struct static_tree_desc_s {
+    const ct_data *static_tree;  /* static tree or NULL */
+    const intf *extra_bits;      /* extra bits for each code or NULL */
+    int     extra_base;          /* base index for extra_bits */
+    int     elems;               /* max number of elements in the tree */
+    int     max_length;          /* max bit length for the codes */
+};
+
+local static_tree_desc  static_l_desc =
+{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
+
+local static_tree_desc  static_d_desc =
+{static_dtree, extra_dbits, 0,          D_CODES, MAX_BITS};
+
+local static_tree_desc  static_bl_desc =
+{(const ct_data *)0, extra_blbits, 0,   BL_CODES, MAX_BL_BITS};
+
+/* ===========================================================================
+ * Local (static) routines in this file.
+ */
+
+local void tr_static_init OF((void));
+local void init_block     OF((deflate_state *s));
+local void pqdownheap     OF((deflate_state *s, ct_data *tree, int k));
+local void gen_bitlen     OF((deflate_state *s, tree_desc *desc));
+local void gen_codes      OF((ct_data *tree, int max_code, ushf *bl_count));
+local void build_tree     OF((deflate_state *s, tree_desc *desc));
+local void scan_tree      OF((deflate_state *s, ct_data *tree, int max_code));
+local void send_tree      OF((deflate_state *s, ct_data *tree, int max_code));
+local int  build_bl_tree  OF((deflate_state *s));
+local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
+                              int blcodes));
+local void compress_block OF((deflate_state *s, ct_data *ltree,
+                              ct_data *dtree));
+local void set_data_type  OF((deflate_state *s));
+local unsigned bi_reverse OF((unsigned value, int length));
+local void bi_windup      OF((deflate_state *s));
+local void bi_flush       OF((deflate_state *s));
+local void copy_block     OF((deflate_state *s, charf *buf, unsigned len,
+                              int header));
+
+#ifdef GEN_TREES_H
+local void gen_trees_header OF((void));
+#endif
+
+#ifndef DEBUG
+#  define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
+   /* Send a code of the given tree. c and tree must not have side effects */
+
+#else /* DEBUG */
+#  define send_code(s, c, tree) \
+     { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
+       send_bits(s, tree[c].Code, tree[c].Len); }
+#endif
+
+/* ===========================================================================
+ * Output a short LSB first on the stream.
+ * IN assertion: there is enough room in pendingBuf.
+ */
+#define put_short(s, w) { \
+    put_byte(s, (uch)((w) & 0xff)); \
+    put_byte(s, (uch)((ush)(w) >> 8)); \
+}
+
+/* ===========================================================================
+ * Send a value on a given number of bits.
+ * IN assertion: length <= 16 and value fits in length bits.
+ */
+#ifdef DEBUG
+local void send_bits      OF((deflate_state *s, int value, int length));
+
+local void send_bits(s, value, length)
+    deflate_state *s;
+    int value;  /* value to send */
+    int length; /* number of bits */
+{
+    Tracevv((stderr," l %2d v %4x ", length, value));
+    Assert(length > 0 && length <= 15, "invalid length");
+    s->bits_sent += (ulg)length;
+
+    /* If not enough room in bi_buf, use (valid) bits from bi_buf and
+     * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
+     * unused bits in value.
+     */
+    if (s->bi_valid > (int)Buf_size - length) {
+        s->bi_buf |= (value << s->bi_valid);
+        put_short(s, s->bi_buf);
+        s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
+        s->bi_valid += length - Buf_size;
+    } else {
+        s->bi_buf |= value << s->bi_valid;
+        s->bi_valid += length;
+    }
+}
+#else /* !DEBUG */
+
+#define send_bits(s, value, length) \
+{ int len = length;\
+  if (s->bi_valid > (int)Buf_size - len) {\
+    int val = value;\
+    s->bi_buf |= (val << s->bi_valid);\
+    put_short(s, s->bi_buf);\
+    s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
+    s->bi_valid += len - Buf_size;\
+  } else {\
+    s->bi_buf |= (value) << s->bi_valid;\
+    s->bi_valid += len;\
+  }\
+}
+#endif /* DEBUG */
+
+
+/* the arguments must not have side effects */
+
+/* ===========================================================================
+ * Initialize the various 'constant' tables.
+ */
+local void tr_static_init()
+{
+#if defined(GEN_TREES_H) || !defined(STDC)
+    static int static_init_done = 0;
+    int n;        /* iterates over tree elements */
+    int bits;     /* bit counter */
+    int length;   /* length value */
+    int code;     /* code value */
+    int dist;     /* distance index */
+    ush bl_count[MAX_BITS+1];
+    /* number of codes at each bit length for an optimal tree */
+
+    if (static_init_done) return;
+
+    /* For some embedded targets, global variables are not initialized: */
+    static_l_desc.static_tree = static_ltree;
+    static_l_desc.extra_bits = extra_lbits;
+    static_d_desc.static_tree = static_dtree;
+    static_d_desc.extra_bits = extra_dbits;
+    static_bl_desc.extra_bits = extra_blbits;
+
+    /* Initialize the mapping length (0..255) -> length code (0..28) */
+    length = 0;
+    for (code = 0; code < LENGTH_CODES-1; code++) {
+        base_length[code] = length;
+        for (n = 0; n < (1<<extra_lbits[code]); n++) {
+            _length_code[length++] = (uch)code;
+        }
+    }
+    Assert (length == 256, "tr_static_init: length != 256");
+    /* Note that the length 255 (match length 258) can be represented
+     * in two different ways: code 284 + 5 bits or code 285, so we
+     * overwrite length_code[255] to use the best encoding:
+     */
+    _length_code[length-1] = (uch)code;
+
+    /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
+    dist = 0;
+    for (code = 0 ; code < 16; code++) {
+        base_dist[code] = dist;
+        for (n = 0; n < (1<<extra_dbits[code]); n++) {
+            _dist_code[dist++] = (uch)code;
+        }
+    }
+    Assert (dist == 256, "tr_static_init: dist != 256");
+    dist >>= 7; /* from now on, all distances are divided by 128 */
+    for ( ; code < D_CODES; code++) {
+        base_dist[code] = dist << 7;
+        for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
+            _dist_code[256 + dist++] = (uch)code;
+        }
+    }
+    Assert (dist == 256, "tr_static_init: 256+dist != 512");
+
+    /* Construct the codes of the static literal tree */
+    for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
+    n = 0;
+    while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
+    while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
+    while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
+    while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
+    /* Codes 286 and 287 do not exist, but we must include them in the
+     * tree construction to get a canonical Huffman tree (longest code
+     * all ones)
+     */
+    gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
+
+    /* The static distance tree is trivial: */
+    for (n = 0; n < D_CODES; n++) {
+        static_dtree[n].Len = 5;
+        static_dtree[n].Code = bi_reverse((unsigned)n, 5);
+    }
+    static_init_done = 1;
+
+#  ifdef GEN_TREES_H
+    gen_trees_header();
+#  endif
+#endif /* defined(GEN_TREES_H) || !defined(STDC) */
+}
+
+/* ===========================================================================
+ * Genererate the file trees.h describing the static trees.
+ */
+#ifdef GEN_TREES_H
+#  ifndef DEBUG
+#    include <stdio.h>
+#  endif
+
+#  define SEPARATOR(i, last, width) \
+      ((i) == (last)? "\n};\n\n" :    \
+       ((i) % (width) == (width)-1 ? ",\n" : ", "))
+
+void gen_trees_header()
+{
+    FILE *header = fopen("trees.h", "w");
+    int i;
+
+    Assert (header != NULL, "Can't open trees.h");
+    fprintf(header,
+            "/* header created automatically with -DGEN_TREES_H */\n\n");
+
+    fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
+    for (i = 0; i < L_CODES+2; i++) {
+        fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
+                static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
+    }
+
+    fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
+    for (i = 0; i < D_CODES; i++) {
+        fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
+                static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
+    }
+
+    fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n");
+    for (i = 0; i < DIST_CODE_LEN; i++) {
+        fprintf(header, "%2u%s", _dist_code[i],
+                SEPARATOR(i, DIST_CODE_LEN-1, 20));
+    }
+
+    fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
+    for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
+        fprintf(header, "%2u%s", _length_code[i],
+                SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
+    }
+
+    fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
+    for (i = 0; i < LENGTH_CODES; i++) {
+        fprintf(header, "%1u%s", base_length[i],
+                SEPARATOR(i, LENGTH_CODES-1, 20));
+    }
+
+    fprintf(header, "local const int base_dist[D_CODES] = {\n");
+    for (i = 0; i < D_CODES; i++) {
+        fprintf(header, "%5u%s", base_dist[i],
+                SEPARATOR(i, D_CODES-1, 10));
+    }
+
+    fclose(header);
+}
+#endif /* GEN_TREES_H */
+
+/* ===========================================================================
+ * Initialize the tree data structures for a new zlib stream.
+ */
+void _tr_init(s)
+    deflate_state *s;
+{
+    tr_static_init();
+
+    s->l_desc.dyn_tree = s->dyn_ltree;
+    s->l_desc.stat_desc = &static_l_desc;
+
+    s->d_desc.dyn_tree = s->dyn_dtree;
+    s->d_desc.stat_desc = &static_d_desc;
+
+    s->bl_desc.dyn_tree = s->bl_tree;
+    s->bl_desc.stat_desc = &static_bl_desc;
+
+    s->bi_buf = 0;
+    s->bi_valid = 0;
+    s->last_eob_len = 8; /* enough lookahead for inflate */
+#ifdef DEBUG
+    s->compressed_len = 0L;
+    s->bits_sent = 0L;
+#endif
+
+    /* Initialize the first block of the first file: */
+    init_block(s);
+}
+
+/* ===========================================================================
+ * Initialize a new block.
+ */
+local void init_block(s)
+    deflate_state *s;
+{
+    int n; /* iterates over tree elements */
+
+    /* Initialize the trees. */
+    for (n = 0; n < L_CODES;  n++) s->dyn_ltree[n].Freq = 0;
+    for (n = 0; n < D_CODES;  n++) s->dyn_dtree[n].Freq = 0;
+    for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
+
+    s->dyn_ltree[END_BLOCK].Freq = 1;
+    s->opt_len = s->static_len = 0L;
+    s->last_lit = s->matches = 0;
+}
+
+#define SMALLEST 1
+/* Index within the heap array of least frequent node in the Huffman tree */
+
+
+/* ===========================================================================
+ * Remove the smallest element from the heap and recreate the heap with
+ * one less element. Updates heap and heap_len.
+ */
+#define pqremove(s, tree, top) \
+{\
+    top = s->heap[SMALLEST]; \
+    s->heap[SMALLEST] = s->heap[s->heap_len--]; \
+    pqdownheap(s, tree, SMALLEST); \
+}
+
+/* ===========================================================================
+ * Compares to subtrees, using the tree depth as tie breaker when
+ * the subtrees have equal frequency. This minimizes the worst case length.
+ */
+#define smaller(tree, n, m, depth) \
+   (tree[n].Freq < tree[m].Freq || \
+   (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
+
+/* ===========================================================================
+ * Restore the heap property by moving down the tree starting at node k,
+ * exchanging a node with the smallest of its two sons if necessary, stopping
+ * when the heap property is re-established (each father smaller than its
+ * two sons).
+ */
+local void pqdownheap(s, tree, k)
+    deflate_state *s;
+    ct_data *tree;  /* the tree to restore */
+    int k;               /* node to move down */
+{
+    int v = s->heap[k];
+    int j = k << 1;  /* left son of k */
+    while (j <= s->heap_len) {
+        /* Set j to the smallest of the two sons: */
+        if (j < s->heap_len &&
+            smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
+            j++;
+        }
+        /* Exit if v is smaller than both sons */
+        if (smaller(tree, v, s->heap[j], s->depth)) break;
+
+        /* Exchange v with the smallest son */
+        s->heap[k] = s->heap[j];  k = j;
+
+        /* And continue down the tree, setting j to the left son of k */
+        j <<= 1;
+    }
+    s->heap[k] = v;
+}
+
+/* ===========================================================================
+ * Compute the optimal bit lengths for a tree and update the total bit length
+ * for the current block.
+ * IN assertion: the fields freq and dad are set, heap[heap_max] and
+ *    above are the tree nodes sorted by increasing frequency.
+ * OUT assertions: the field len is set to the optimal bit length, the
+ *     array bl_count contains the frequencies for each bit length.
+ *     The length opt_len is updated; static_len is also updated if stree is
+ *     not null.
+ */
+local void gen_bitlen(s, desc)
+    deflate_state *s;
+    tree_desc *desc;    /* the tree descriptor */
+{
+    ct_data *tree        = desc->dyn_tree;
+    int max_code         = desc->max_code;
+    const ct_data *stree = desc->stat_desc->static_tree;
+    const intf *extra    = desc->stat_desc->extra_bits;
+    int base             = desc->stat_desc->extra_base;
+    int max_length       = desc->stat_desc->max_length;
+    int h;              /* heap index */
+    int n, m;           /* iterate over the tree elements */
+    int bits;           /* bit length */
+    int xbits;          /* extra bits */
+    ush f;              /* frequency */
+    int overflow = 0;   /* number of elements with bit length too large */
+
+    for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
+
+    /* In a first pass, compute the optimal bit lengths (which may
+     * overflow in the case of the bit length tree).
+     */
+    tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
+
+    for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
+        n = s->heap[h];
+        bits = tree[tree[n].Dad].Len + 1;
+        if (bits > max_length) bits = max_length, overflow++;
+        tree[n].Len = (ush)bits;
+        /* We overwrite tree[n].Dad which is no longer needed */
+
+        if (n > max_code) continue; /* not a leaf node */
+
+        s->bl_count[bits]++;
+        xbits = 0;
+        if (n >= base) xbits = extra[n-base];
+        f = tree[n].Freq;
+        s->opt_len += (ulg)f * (bits + xbits);
+        if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
+    }
+    if (overflow == 0) return;
+
+    Trace((stderr,"\nbit length overflow\n"));
+    /* This happens for example on obj2 and pic of the Calgary corpus */
+
+    /* Find the first bit length which could increase: */
+    do {
+        bits = max_length-1;
+        while (s->bl_count[bits] == 0) bits--;
+        s->bl_count[bits]--;      /* move one leaf down the tree */
+        s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
+        s->bl_count[max_length]--;
+        /* The brother of the overflow item also moves one step up,
+         * but this does not affect bl_count[max_length]
+         */
+        overflow -= 2;
+    } while (overflow > 0);
+
+    /* Now recompute all bit lengths, scanning in increasing frequency.
+     * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
+     * lengths instead of fixing only the wrong ones. This idea is taken
+     * from 'ar' written by Haruhiko Okumura.)
+     */
+    for (bits = max_length; bits != 0; bits--) {
+        n = s->bl_count[bits];
+        while (n != 0) {
+            m = s->heap[--h];
+            if (m > max_code) continue;
+            if ((unsigned) tree[m].Len != (unsigned) bits) {
+                Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
+                s->opt_len += ((long)bits - (long)tree[m].Len)
+                              *(long)tree[m].Freq;
+                tree[m].Len = (ush)bits;
+            }
+            n--;
+        }
+    }
+}
+
+/* ===========================================================================
+ * Generate the codes for a given tree and bit counts (which need not be
+ * optimal).
+ * IN assertion: the array bl_count contains the bit length statistics for
+ * the given tree and the field len is set for all tree elements.
+ * OUT assertion: the field code is set for all tree elements of non
+ *     zero code length.
+ */
+local void gen_codes (tree, max_code, bl_count)
+    ct_data *tree;             /* the tree to decorate */
+    int max_code;              /* largest code with non zero frequency */
+    ushf *bl_count;            /* number of codes at each bit length */
+{
+    ush next_code[MAX_BITS+1]; /* next code value for each bit length */
+    ush code = 0;              /* running code value */
+    int bits;                  /* bit index */
+    int n;                     /* code index */
+
+    /* The distribution counts are first used to generate the code values
+     * without bit reversal.
+     */
+    for (bits = 1; bits <= MAX_BITS; bits++) {
+        next_code[bits] = code = (code + bl_count[bits-1]) << 1;
+    }
+    /* Check that the bit counts in bl_count are consistent. The last code
+     * must be all ones.
+     */
+    Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
+            "inconsistent bit counts");
+    Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
+
+    for (n = 0;  n <= max_code; n++) {
+        int len = tree[n].Len;
+        if (len == 0) continue;
+        /* Now reverse the bits */
+        tree[n].Code = bi_reverse(next_code[len]++, len);
+
+        Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
+             n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
+    }
+}
+
+/* ===========================================================================
+ * Construct one Huffman tree and assigns the code bit strings and lengths.
+ * Update the total bit length for the current block.
+ * IN assertion: the field freq is set for all tree elements.
+ * OUT assertions: the fields len and code are set to the optimal bit length
+ *     and corresponding code. The length opt_len is updated; static_len is
+ *     also updated if stree is not null. The field max_code is set.
+ */
+local void build_tree(s, desc)
+    deflate_state *s;
+    tree_desc *desc; /* the tree descriptor */
+{
+    ct_data *tree         = desc->dyn_tree;
+    const ct_data *stree  = desc->stat_desc->static_tree;
+    int elems             = desc->stat_desc->elems;
+    int n, m;          /* iterate over heap elements */
+    int max_code = -1; /* largest code with non zero frequency */
+    int node;          /* new node being created */
+
+    /* Construct the initial heap, with least frequent element in
+     * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
+     * heap[0] is not used.
+     */
+    s->heap_len = 0, s->heap_max = HEAP_SIZE;
+
+    for (n = 0; n < elems; n++) {
+        if (tree[n].Freq != 0) {
+            s->heap[++(s->heap_len)] = max_code = n;
+            s->depth[n] = 0;
+        } else {
+            tree[n].Len = 0;
+        }
+    }
+
+    /* The pkzip format requires that at least one distance code exists,
+     * and that at least one bit should be sent even if there is only one
+     * possible code. So to avoid special checks later on we force at least
+     * two codes of non zero frequency.
+     */
+    while (s->heap_len < 2) {
+        node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
+        tree[node].Freq = 1;
+        s->depth[node] = 0;
+        s->opt_len--; if (stree) s->static_len -= stree[node].Len;
+        /* node is 0 or 1 so it does not have extra bits */
+    }
+    desc->max_code = max_code;
+
+    /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
+     * establish sub-heaps of increasing lengths:
+     */
+    for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
+
+    /* Construct the Huffman tree by repeatedly combining the least two
+     * frequent nodes.
+     */
+    node = elems;              /* next internal node of the tree */
+    do {
+        pqremove(s, tree, n);  /* n = node of least frequency */
+        m = s->heap[SMALLEST]; /* m = node of next least frequency */
+
+        s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
+        s->heap[--(s->heap_max)] = m;
+
+        /* Create a new node father of n and m */
+        tree[node].Freq = tree[n].Freq + tree[m].Freq;
+        s->depth[node] = (uch)((s->depth[n] >= s->depth[m] ?
+                                s->depth[n] : s->depth[m]) + 1);
+        tree[n].Dad = tree[m].Dad = (ush)node;
+#ifdef DUMP_BL_TREE
+        if (tree == s->bl_tree) {
+            fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
+                    node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
+        }
+#endif
+        /* and insert the new node in the heap */
+        s->heap[SMALLEST] = node++;
+        pqdownheap(s, tree, SMALLEST);
+
+    } while (s->heap_len >= 2);
+
+    s->heap[--(s->heap_max)] = s->heap[SMALLEST];
+
+    /* At this point, the fields freq and dad are set. We can now
+     * generate the bit lengths.
+     */
+    gen_bitlen(s, (tree_desc *)desc);
+
+    /* The field len is now set, we can generate the bit codes */
+    gen_codes ((ct_data *)tree, max_code, s->bl_count);
+}
+
+/* ===========================================================================
+ * Scan a literal or distance tree to determine the frequencies of the codes
+ * in the bit length tree.
+ */
+local void scan_tree (s, tree, max_code)
+    deflate_state *s;
+    ct_data *tree;   /* the tree to be scanned */
+    int max_code;    /* and its largest code of non zero frequency */
+{
+    int n;                     /* iterates over all tree elements */
+    int prevlen = -1;          /* last emitted length */
+    int curlen;                /* length of current code */
+    int nextlen = tree[0].Len; /* length of next code */
+    int count = 0;             /* repeat count of the current code */
+    int max_count = 7;         /* max repeat count */
+    int min_count = 4;         /* min repeat count */
+
+    if (nextlen == 0) max_count = 138, min_count = 3;
+    tree[max_code+1].Len = (ush)0xffff; /* guard */
+
+    for (n = 0; n <= max_code; n++) {
+        curlen = nextlen; nextlen = tree[n+1].Len;
+        if (++count < max_count && curlen == nextlen) {
+            continue;
+        } else if (count < min_count) {
+            s->bl_tree[curlen].Freq += count;
+        } else if (curlen != 0) {
+            if (curlen != prevlen) s->bl_tree[curlen].Freq++;
+            s->bl_tree[REP_3_6].Freq++;
+        } else if (count <= 10) {
+            s->bl_tree[REPZ_3_10].Freq++;
+        } else {
+            s->bl_tree[REPZ_11_138].Freq++;
+        }
+        count = 0; prevlen = curlen;
+        if (nextlen == 0) {
+            max_count = 138, min_count = 3;
+        } else if (curlen == nextlen) {
+            max_count = 6, min_count = 3;
+        } else {
+            max_count = 7, min_count = 4;
+        }
+    }
+}
+
+/* ===========================================================================
+ * Send a literal or distance tree in compressed form, using the codes in
+ * bl_tree.
+ */
+local void send_tree (s, tree, max_code)
+    deflate_state *s;
+    ct_data *tree; /* the tree to be scanned */
+    int max_code;       /* and its largest code of non zero frequency */
+{
+    int n;                     /* iterates over all tree elements */
+    int prevlen = -1;          /* last emitted length */
+    int curlen;                /* length of current code */
+    int nextlen = tree[0].Len; /* length of next code */
+    int count = 0;             /* repeat count of the current code */
+    int max_count = 7;         /* max repeat count */
+    int min_count = 4;         /* min repeat count */
+
+    /* tree[max_code+1].Len = -1; */  /* guard already set */
+    if (nextlen == 0) max_count = 138, min_count = 3;
+
+    for (n = 0; n <= max_code; n++) {
+        curlen = nextlen; nextlen = tree[n+1].Len;
+        if (++count < max_count && curlen == nextlen) {
+            continue;
+        } else if (count < min_count) {
+            do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
+
+        } else if (curlen != 0) {
+            if (curlen != prevlen) {
+                send_code(s, curlen, s->bl_tree); count--;
+            }
+            Assert(count >= 3 && count <= 6, " 3_6?");
+            send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
+
+        } else if (count <= 10) {
+            send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
+
+        } else {
+            send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
+        }
+        count = 0; prevlen = curlen;
+        if (nextlen == 0) {
+            max_count = 138, min_count = 3;
+        } else if (curlen == nextlen) {
+            max_count = 6, min_count = 3;
+        } else {
+            max_count = 7, min_count = 4;
+        }
+    }
+}
+
+/* ===========================================================================
+ * Construct the Huffman tree for the bit lengths and return the index in
+ * bl_order of the last bit length code to send.
+ */
+local int build_bl_tree(s)
+    deflate_state *s;
+{
+    int max_blindex;  /* index of last bit length code of non zero freq */
+
+    /* Determine the bit length frequencies for literal and distance trees */
+    scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
+    scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
+
+    /* Build the bit length tree: */
+    build_tree(s, (tree_desc *)(&(s->bl_desc)));
+    /* opt_len now includes the length of the tree representations, except
+     * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
+     */
+
+    /* Determine the number of bit length codes to send. The pkzip format
+     * requires that at least 4 bit length codes be sent. (appnote.txt says
+     * 3 but the actual value used is 4.)
+     */
+    for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
+        if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
+    }
+    /* Update opt_len to include the bit length tree and counts */
+    s->opt_len += 3*(max_blindex+1) + 5+5+4;
+    Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
+            s->opt_len, s->static_len));
+
+    return max_blindex;
+}
+
+/* ===========================================================================
+ * Send the header for a block using dynamic Huffman trees: the counts, the
+ * lengths of the bit length codes, the literal tree and the distance tree.
+ * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
+ */
+local void send_all_trees(s, lcodes, dcodes, blcodes)
+    deflate_state *s;
+    int lcodes, dcodes, blcodes; /* number of codes for each tree */
+{
+    int rank;                    /* index in bl_order */
+
+    Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
+    Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
+            "too many codes");
+    Tracev((stderr, "\nbl counts: "));
+    send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
+    send_bits(s, dcodes-1,   5);
+    send_bits(s, blcodes-4,  4); /* not -3 as stated in appnote.txt */
+    for (rank = 0; rank < blcodes; rank++) {
+        Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
+        send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
+    }
+    Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
+
+    send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
+    Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
+
+    send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
+    Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
+}
+
+/* ===========================================================================
+ * Send a stored block
+ */
+void _tr_stored_block(s, buf, stored_len, eof)
+    deflate_state *s;
+    charf *buf;       /* input block */
+    ulg stored_len;   /* length of input block */
+    int eof;          /* true if this is the last block for a file */
+{
+    send_bits(s, (STORED_BLOCK<<1)+eof, 3);  /* send block type */
+#ifdef DEBUG
+    s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
+    s->compressed_len += (stored_len + 4) << 3;
+#endif
+    copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
+}
+
+/* ===========================================================================
+ * Send one empty static block to give enough lookahead for inflate.
+ * This takes 10 bits, of which 7 may remain in the bit buffer.
+ * The current inflate code requires 9 bits of lookahead. If the
+ * last two codes for the previous block (real code plus EOB) were coded
+ * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
+ * the last real code. In this case we send two empty static blocks instead
+ * of one. (There are no problems if the previous block is stored or fixed.)
+ * To simplify the code, we assume the worst case of last real code encoded
+ * on one bit only.
+ */
+void _tr_align(s)
+    deflate_state *s;
+{
+    send_bits(s, STATIC_TREES<<1, 3);
+    send_code(s, END_BLOCK, static_ltree);
+#ifdef DEBUG
+    s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
+#endif
+    bi_flush(s);
+    /* Of the 10 bits for the empty block, we have already sent
+     * (10 - bi_valid) bits. The lookahead for the last real code (before
+     * the EOB of the previous block) was thus at least one plus the length
+     * of the EOB plus what we have just sent of the empty static block.
+     */
+    if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
+        send_bits(s, STATIC_TREES<<1, 3);
+        send_code(s, END_BLOCK, static_ltree);
+#ifdef DEBUG
+        s->compressed_len += 10L;
+#endif
+        bi_flush(s);
+    }
+    s->last_eob_len = 7;
+}
+
+/* ===========================================================================
+ * Determine the best encoding for the current block: dynamic trees, static
+ * trees or store, and output the encoded block to the zip file.
+ */
+void _tr_flush_block(s, buf, stored_len, eof)
+    deflate_state *s;
+    charf *buf;       /* input block, or NULL if too old */
+    ulg stored_len;   /* length of input block */
+    int eof;          /* true if this is the last block for a file */
+{
+    ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
+    int max_blindex = 0;  /* index of last bit length code of non zero freq */
+
+    /* Build the Huffman trees unless a stored block is forced */
+    if (s->level > 0) {
+
+        /* Check if the file is binary or text */
+        if (stored_len > 0 && s->strm->data_type == Z_UNKNOWN)
+            set_data_type(s);
+
+        /* Construct the literal and distance trees */
+        build_tree(s, (tree_desc *)(&(s->l_desc)));
+        Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
+                s->static_len));
+
+        build_tree(s, (tree_desc *)(&(s->d_desc)));
+        Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
+                s->static_len));
+        /* At this point, opt_len and static_len are the total bit lengths of
+         * the compressed block data, excluding the tree representations.
+         */
+
+        /* Build the bit length tree for the above two trees, and get the index
+         * in bl_order of the last bit length code to send.
+         */
+        max_blindex = build_bl_tree(s);
+
+        /* Determine the best encoding. Compute the block lengths in bytes. */
+        opt_lenb = (s->opt_len+3+7)>>3;
+        static_lenb = (s->static_len+3+7)>>3;
+
+        Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
+                opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
+                s->last_lit));
+
+        if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
+
+    } else {
+        Assert(buf != (char*)0, "lost buf");
+        opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
+    }
+
+#ifdef FORCE_STORED
+    if (buf != (char*)0) { /* force stored block */
+#else
+    if (stored_len+4 <= opt_lenb && buf != (char*)0) {
+                       /* 4: two words for the lengths */
+#endif
+        /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
+         * Otherwise we can't have processed more than WSIZE input bytes since
+         * the last block flush, because compression would have been
+         * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
+         * transform a block into a stored block.
+         */
+        _tr_stored_block(s, buf, stored_len, eof);
+
+#ifdef FORCE_STATIC
+    } else if (static_lenb >= 0) { /* force static trees */
+#else
+    } else if (s->strategy == Z_FIXED || static_lenb == opt_lenb) {
+#endif
+        send_bits(s, (STATIC_TREES<<1)+eof, 3);
+        compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
+#ifdef DEBUG
+        s->compressed_len += 3 + s->static_len;
+#endif
+    } else {
+        send_bits(s, (DYN_TREES<<1)+eof, 3);
+        send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
+                       max_blindex+1);
+        compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
+#ifdef DEBUG
+        s->compressed_len += 3 + s->opt_len;
+#endif
+    }
+    Assert (s->compressed_len == s->bits_sent, "bad compressed size");
+    /* The above check is made mod 2^32, for files larger than 512 MB
+     * and uLong implemented on 32 bits.
+     */
+    init_block(s);
+
+    if (eof) {
+        bi_windup(s);
+#ifdef DEBUG
+        s->compressed_len += 7;  /* align on byte boundary */
+#endif
+    }
+    Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
+           s->compressed_len-7*eof));
+}
+
+/* ===========================================================================
+ * Save the match info and tally the frequency counts. Return true if
+ * the current block must be flushed.
+ */
+int _tr_tally (s, dist, lc)
+    deflate_state *s;
+    unsigned dist;  /* distance of matched string */
+    unsigned lc;    /* match length-MIN_MATCH or unmatched char (if dist==0) */
+{
+    s->d_buf[s->last_lit] = (ush)dist;
+    s->l_buf[s->last_lit++] = (uch)lc;
+    if (dist == 0) {
+        /* lc is the unmatched char */
+        s->dyn_ltree[lc].Freq++;
+    } else {
+        s->matches++;
+        /* Here, lc is the match length - MIN_MATCH */
+        dist--;             /* dist = match distance - 1 */
+        Assert((ush)dist < (ush)MAX_DIST(s) &&
+               (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
+               (ush)d_code(dist) < (ush)D_CODES,  "_tr_tally: bad match");
+
+        s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
+        s->dyn_dtree[d_code(dist)].Freq++;
+    }
+
+#ifdef TRUNCATE_BLOCK
+    /* Try to guess if it is profitable to stop the current block here */
+    if ((s->last_lit & 0x1fff) == 0 && s->level > 2) {
+        /* Compute an upper bound for the compressed length */
+        ulg out_length = (ulg)s->last_lit*8L;
+        ulg in_length = (ulg)((long)s->strstart - s->block_start);
+        int dcode;
+        for (dcode = 0; dcode < D_CODES; dcode++) {
+            out_length += (ulg)s->dyn_dtree[dcode].Freq *
+                (5L+extra_dbits[dcode]);
+        }
+        out_length >>= 3;
+        Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
+               s->last_lit, in_length, out_length,
+               100L - out_length*100L/in_length));
+        if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
+    }
+#endif
+    return (s->last_lit == s->lit_bufsize-1);
+    /* We avoid equality with lit_bufsize because of wraparound at 64K
+     * on 16 bit machines and because stored blocks are restricted to
+     * 64K-1 bytes.
+     */
+}
+
+/* ===========================================================================
+ * Send the block data compressed using the given Huffman trees
+ */
+local void compress_block(s, ltree, dtree)
+    deflate_state *s;
+    ct_data *ltree; /* literal tree */
+    ct_data *dtree; /* distance tree */
+{
+    unsigned dist;      /* distance of matched string */
+    int lc;             /* match length or unmatched char (if dist == 0) */
+    unsigned lx = 0;    /* running index in l_buf */
+    unsigned code;      /* the code to send */
+    int extra;          /* number of extra bits to send */
+
+    if (s->last_lit != 0) do {
+        dist = s->d_buf[lx];
+        lc = s->l_buf[lx++];
+        if (dist == 0) {
+            send_code(s, lc, ltree); /* send a literal byte */
+            Tracecv(isgraph(lc), (stderr," '%c' ", lc));
+        } else {
+            /* Here, lc is the match length - MIN_MATCH */
+            code = _length_code[lc];
+            send_code(s, code+LITERALS+1, ltree); /* send the length code */
+            extra = extra_lbits[code];
+            if (extra != 0) {
+                lc -= base_length[code];
+                send_bits(s, lc, extra);       /* send the extra length bits */
+            }
+            dist--; /* dist is now the match distance - 1 */
+            code = d_code(dist);
+            Assert (code < D_CODES, "bad d_code");
+
+            send_code(s, code, dtree);       /* send the distance code */
+            extra = extra_dbits[code];
+            if (extra != 0) {
+                dist -= base_dist[code];
+                send_bits(s, dist, extra);   /* send the extra distance bits */
+            }
+        } /* literal or match pair ? */
+
+        /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
+        Assert((uInt)(s->pending) < s->lit_bufsize + 2*lx,
+               "pendingBuf overflow");
+
+    } while (lx < s->last_lit);
+
+    send_code(s, END_BLOCK, ltree);
+    s->last_eob_len = ltree[END_BLOCK].Len;
+}
+
+/* ===========================================================================
+ * Set the data type to BINARY or TEXT, using a crude approximation:
+ * set it to Z_TEXT if all symbols are either printable characters (33 to 255)
+ * or white spaces (9 to 13, or 32); or set it to Z_BINARY otherwise.
+ * IN assertion: the fields Freq of dyn_ltree are set.
+ */
+local void set_data_type(s)
+    deflate_state *s;
+{
+    int n;
+
+    for (n = 0; n < 9; n++)
+        if (s->dyn_ltree[n].Freq != 0)
+            break;
+    if (n == 9)
+        for (n = 14; n < 32; n++)
+            if (s->dyn_ltree[n].Freq != 0)
+                break;
+    s->strm->data_type = (n == 32) ? Z_TEXT : Z_BINARY;
+}
+
+/* ===========================================================================
+ * Reverse the first len bits of a code, using straightforward code (a faster
+ * method would use a table)
+ * IN assertion: 1 <= len <= 15
+ */
+local unsigned bi_reverse(code, len)
+    unsigned code; /* the value to invert */
+    int len;       /* its bit length */
+{
+    register unsigned res = 0;
+    do {
+        res |= code & 1;
+        code >>= 1, res <<= 1;
+    } while (--len > 0);
+    return res >> 1;
+}
+
+/* ===========================================================================
+ * Flush the bit buffer, keeping at most 7 bits in it.
+ */
+local void bi_flush(s)
+    deflate_state *s;
+{
+    if (s->bi_valid == 16) {
+        put_short(s, s->bi_buf);
+        s->bi_buf = 0;
+        s->bi_valid = 0;
+    } else if (s->bi_valid >= 8) {
+        put_byte(s, (Byte)s->bi_buf);
+        s->bi_buf >>= 8;
+        s->bi_valid -= 8;
+    }
+}
+
+/* ===========================================================================
+ * Flush the bit buffer and align the output on a byte boundary
+ */
+local void bi_windup(s)
+    deflate_state *s;
+{
+    if (s->bi_valid > 8) {
+        put_short(s, s->bi_buf);
+    } else if (s->bi_valid > 0) {
+        put_byte(s, (Byte)s->bi_buf);
+    }
+    s->bi_buf = 0;
+    s->bi_valid = 0;
+#ifdef DEBUG
+    s->bits_sent = (s->bits_sent+7) & ~7;
+#endif
+}
+
+/* ===========================================================================
+ * Copy a stored block, storing first the length and its
+ * one's complement if requested.
+ */
+local void copy_block(s, buf, len, header)
+    deflate_state *s;
+    charf    *buf;    /* the input data */
+    unsigned len;     /* its length */
+    int      header;  /* true if block header must be written */
+{
+    bi_windup(s);        /* align on byte boundary */
+    s->last_eob_len = 8; /* enough lookahead for inflate */
+
+    if (header) {
+        put_short(s, (ush)len);
+        put_short(s, (ush)~len);
+#ifdef DEBUG
+        s->bits_sent += 2*16;
+#endif
+    }
+#ifdef DEBUG
+    s->bits_sent += (ulg)len<<3;
+#endif
+    while (len--) {
+        put_byte(s, *buf++);
+    }
+}
diff --git a/gs/zlib/trees.h b/gs/zlib/trees.h
new file mode 100644
index 000000000..72facf900
--- /dev/null
+++ b/gs/zlib/trees.h
@@ -0,0 +1,128 @@
+/* header created automatically with -DGEN_TREES_H */
+
+local const ct_data static_ltree[L_CODES+2] = {
+{{ 12},{  8}}, {{140},{  8}}, {{ 76},{  8}}, {{204},{  8}}, {{ 44},{  8}},
+{{172},{  8}}, {{108},{  8}}, {{236},{  8}}, {{ 28},{  8}}, {{156},{  8}},
+{{ 92},{  8}}, {{220},{  8}}, {{ 60},{  8}}, {{188},{  8}}, {{124},{  8}},
+{{252},{  8}}, {{  2},{  8}}, {{130},{  8}}, {{ 66},{  8}}, {{194},{  8}},
+{{ 34},{  8}}, {{162},{  8}}, {{ 98},{  8}}, {{226},{  8}}, {{ 18},{  8}},
+{{146},{  8}}, {{ 82},{  8}}, {{210},{  8}}, {{ 50},{  8}}, {{178},{  8}},
+{{114},{  8}}, {{242},{  8}}, {{ 10},{  8}}, {{138},{  8}}, {{ 74},{  8}},
+{{202},{  8}}, {{ 42},{  8}}, {{170},{  8}}, {{106},{  8}}, {{234},{  8}},
+{{ 26},{  8}}, {{154},{  8}}, {{ 90},{  8}}, {{218},{  8}}, {{ 58},{  8}},
+{{186},{  8}}, {{122},{  8}}, {{250},{  8}}, {{  6},{  8}}, {{134},{  8}},
+{{ 70},{  8}}, {{198},{  8}}, {{ 38},{  8}}, {{166},{  8}}, {{102},{  8}},
+{{230},{  8}}, {{ 22},{  8}}, {{150},{  8}}, {{ 86},{  8}}, {{214},{  8}},
+{{ 54},{  8}}, {{182},{  8}}, {{118},{  8}}, {{246},{  8}}, {{ 14},{  8}},
+{{142},{  8}}, {{ 78},{  8}}, {{206},{  8}}, {{ 46},{  8}}, {{174},{  8}},
+{{110},{  8}}, {{238},{  8}}, {{ 30},{  8}}, {{158},{  8}}, {{ 94},{  8}},
+{{222},{  8}}, {{ 62},{  8}}, {{190},{  8}}, {{126},{  8}}, {{254},{  8}},
+{{  1},{  8}}, {{129},{  8}}, {{ 65},{  8}}, {{193},{  8}}, {{ 33},{  8}},
+{{161},{  8}}, {{ 97},{  8}}, {{225},{  8}}, {{ 17},{  8}}, {{145},{  8}},
+{{ 81},{  8}}, {{209},{  8}}, {{ 49},{  8}}, {{177},{  8}}, {{113},{  8}},
+{{241},{  8}}, {{  9},{  8}}, {{137},{  8}}, {{ 73},{  8}}, {{201},{  8}},
+{{ 41},{  8}}, {{169},{  8}}, {{105},{  8}}, {{233},{  8}}, {{ 25},{  8}},
+{{153},{  8}}, {{ 89},{  8}}, {{217},{  8}}, {{ 57},{  8}}, {{185},{  8}},
+{{121},{  8}}, {{249},{  8}}, {{  5},{  8}}, {{133},{  8}}, {{ 69},{  8}},
+{{197},{  8}}, {{ 37},{  8}}, {{165},{  8}}, {{101},{  8}}, {{229},{  8}},
+{{ 21},{  8}}, {{149},{  8}}, {{ 85},{  8}}, {{213},{  8}}, {{ 53},{  8}},
+{{181},{  8}}, {{117},{  8}}, {{245},{  8}}, {{ 13},{  8}}, {{141},{  8}},
+{{ 77},{  8}}, {{205},{  8}}, {{ 45},{  8}}, {{173},{  8}}, {{109},{  8}},
+{{237},{  8}}, {{ 29},{  8}}, {{157},{  8}}, {{ 93},{  8}}, {{221},{  8}},
+{{ 61},{  8}}, {{189},{  8}}, {{125},{  8}}, {{253},{  8}}, {{ 19},{  9}},
+{{275},{  9}}, {{147},{  9}}, {{403},{  9}}, {{ 83},{  9}}, {{339},{  9}},
+{{211},{  9}}, {{467},{  9}}, {{ 51},{  9}}, {{307},{  9}}, {{179},{  9}},
+{{435},{  9}}, {{115},{  9}}, {{371},{  9}}, {{243},{  9}}, {{499},{  9}},
+{{ 11},{  9}}, {{267},{  9}}, {{139},{  9}}, {{395},{  9}}, {{ 75},{  9}},
+{{331},{  9}}, {{203},{  9}}, {{459},{  9}}, {{ 43},{  9}}, {{299},{  9}},
+{{171},{  9}}, {{427},{  9}}, {{107},{  9}}, {{363},{  9}}, {{235},{  9}},
+{{491},{  9}}, {{ 27},{  9}}, {{283},{  9}}, {{155},{  9}}, {{411},{  9}},
+{{ 91},{  9}}, {{347},{  9}}, {{219},{  9}}, {{475},{  9}}, {{ 59},{  9}},
+{{315},{  9}}, {{187},{  9}}, {{443},{  9}}, {{123},{  9}}, {{379},{  9}},
+{{251},{  9}}, {{507},{  9}}, {{  7},{  9}}, {{263},{  9}}, {{135},{  9}},
+{{391},{  9}}, {{ 71},{  9}}, {{327},{  9}}, {{199},{  9}}, {{455},{  9}},
+{{ 39},{  9}}, {{295},{  9}}, {{167},{  9}}, {{423},{  9}}, {{103},{  9}},
+{{359},{  9}}, {{231},{  9}}, {{487},{  9}}, {{ 23},{  9}}, {{279},{  9}},
+{{151},{  9}}, {{407},{  9}}, {{ 87},{  9}}, {{343},{  9}}, {{215},{  9}},
+{{471},{  9}}, {{ 55},{  9}}, {{311},{  9}}, {{183},{  9}}, {{439},{  9}},
+{{119},{  9}}, {{375},{  9}}, {{247},{  9}}, {{503},{  9}}, {{ 15},{  9}},
+{{271},{  9}}, {{143},{  9}}, {{399},{  9}}, {{ 79},{  9}}, {{335},{  9}},
+{{207},{  9}}, {{463},{  9}}, {{ 47},{  9}}, {{303},{  9}}, {{175},{  9}},
+{{431},{  9}}, {{111},{  9}}, {{367},{  9}}, {{239},{  9}}, {{495},{  9}},
+{{ 31},{  9}}, {{287},{  9}}, {{159},{  9}}, {{415},{  9}}, {{ 95},{  9}},
+{{351},{  9}}, {{223},{  9}}, {{479},{  9}}, {{ 63},{  9}}, {{319},{  9}},
+{{191},{  9}}, {{447},{  9}}, {{127},{  9}}, {{383},{  9}}, {{255},{  9}},
+{{511},{  9}}, {{  0},{  7}}, {{ 64},{  7}}, {{ 32},{  7}}, {{ 96},{  7}},
+{{ 16},{  7}}, {{ 80},{  7}}, {{ 48},{  7}}, {{112},{  7}}, {{  8},{  7}},
+{{ 72},{  7}}, {{ 40},{  7}}, {{104},{  7}}, {{ 24},{  7}}, {{ 88},{  7}},
+{{ 56},{  7}}, {{120},{  7}}, {{  4},{  7}}, {{ 68},{  7}}, {{ 36},{  7}},
+{{100},{  7}}, {{ 20},{  7}}, {{ 84},{  7}}, {{ 52},{  7}}, {{116},{  7}},
+{{  3},{  8}}, {{131},{  8}}, {{ 67},{  8}}, {{195},{  8}}, {{ 35},{  8}},
+{{163},{  8}}, {{ 99},{  8}}, {{227},{  8}}
+};
+
+local const ct_data static_dtree[D_CODES] = {
+{{ 0},{ 5}}, {{16},{ 5}}, {{ 8},{ 5}}, {{24},{ 5}}, {{ 4},{ 5}},
+{{20},{ 5}}, {{12},{ 5}}, {{28},{ 5}}, {{ 2},{ 5}}, {{18},{ 5}},
+{{10},{ 5}}, {{26},{ 5}}, {{ 6},{ 5}}, {{22},{ 5}}, {{14},{ 5}},
+{{30},{ 5}}, {{ 1},{ 5}}, {{17},{ 5}}, {{ 9},{ 5}}, {{25},{ 5}},
+{{ 5},{ 5}}, {{21},{ 5}}, {{13},{ 5}}, {{29},{ 5}}, {{ 3},{ 5}},
+{{19},{ 5}}, {{11},{ 5}}, {{27},{ 5}}, {{ 7},{ 5}}, {{23},{ 5}}
+};
+
+const uch _dist_code[DIST_CODE_LEN] = {
+ 0,  1,  2,  3,  4,  4,  5,  5,  6,  6,  6,  6,  7,  7,  7,  7,  8,  8,  8,  8,
+ 8,  8,  8,  8,  9,  9,  9,  9,  9,  9,  9,  9, 10, 10, 10, 10, 10, 10, 10, 10,
+10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
+11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13,
+13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
+13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
+14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
+14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
+14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15,
+15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
+15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
+15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,  0,  0, 16, 17,
+18, 18, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22,
+23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
+24, 24, 24, 24, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
+26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
+26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27,
+27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
+27, 27, 27, 27, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
+28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
+28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
+28, 28, 28, 28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
+29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
+29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
+29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29
+};
+
+const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {
+ 0,  1,  2,  3,  4,  5,  6,  7,  8,  8,  9,  9, 10, 10, 11, 11, 12, 12, 12, 12,
+13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16, 16,
+17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19,
+19, 19, 19, 19, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20,
+21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22,
+22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, 23, 23, 23, 23,
+23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
+24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
+25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
+25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 26, 26, 26,
+26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
+26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
+27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 28
+};
+
+local const int base_length[LENGTH_CODES] = {
+0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56,
+64, 80, 96, 112, 128, 160, 192, 224, 0
+};
+
+local const int base_dist[D_CODES] = {
+    0,     1,     2,     3,     4,     6,     8,    12,    16,    24,
+   32,    48,    64,    96,   128,   192,   256,   384,   512,   768,
+ 1024,  1536,  2048,  3072,  4096,  6144,  8192, 12288, 16384, 24576
+};
+
diff --git a/gs/zlib/uncompr.c b/gs/zlib/uncompr.c
new file mode 100644
index 000000000..b59e3d0de
--- /dev/null
+++ b/gs/zlib/uncompr.c
@@ -0,0 +1,61 @@
+/* uncompr.c -- decompress a memory buffer
+ * Copyright (C) 1995-2003 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* @(#) $Id$ */
+
+#define ZLIB_INTERNAL
+#include "zlib.h"
+
+/* ===========================================================================
+     Decompresses the source buffer into the destination buffer.  sourceLen is
+   the byte length of the source buffer. Upon entry, destLen is the total
+   size of the destination buffer, which must be large enough to hold the
+   entire uncompressed data. (The size of the uncompressed data must have
+   been saved previously by the compressor and transmitted to the decompressor
+   by some mechanism outside the scope of this compression library.)
+   Upon exit, destLen is the actual size of the compressed buffer.
+     This function can be used to decompress a whole file at once if the
+   input file is mmap'ed.
+
+     uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
+   enough memory, Z_BUF_ERROR if there was not enough room in the output
+   buffer, or Z_DATA_ERROR if the input data was corrupted.
+*/
+int ZEXPORT uncompress (dest, destLen, source, sourceLen)
+    Bytef *dest;
+    uLongf *destLen;
+    const Bytef *source;
+    uLong sourceLen;
+{
+    z_stream stream;
+    int err;
+
+    stream.next_in = (Bytef*)source;
+    stream.avail_in = (uInt)sourceLen;
+    /* Check for source > 64K on 16-bit machine: */
+    if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
+
+    stream.next_out = dest;
+    stream.avail_out = (uInt)*destLen;
+    if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
+
+    stream.zalloc = (alloc_func)0;
+    stream.zfree = (free_func)0;
+
+    err = inflateInit(&stream);
+    if (err != Z_OK) return err;
+
+    err = inflate(&stream, Z_FINISH);
+    if (err != Z_STREAM_END) {
+        inflateEnd(&stream);
+        if (err == Z_NEED_DICT || (err == Z_BUF_ERROR && stream.avail_in == 0))
+            return Z_DATA_ERROR;
+        return err;
+    }
+    *destLen = stream.total_out;
+
+    err = inflateEnd(&stream);
+    return err;
+}
diff --git a/gs/zlib/win32/DLL_FAQ.txt b/gs/zlib/win32/DLL_FAQ.txt
new file mode 100644
index 000000000..fb18e0711
--- /dev/null
+++ b/gs/zlib/win32/DLL_FAQ.txt
@@ -0,0 +1,397 @@
+
+            Frequently Asked Questions about ZLIB1.DLL
+
+
+This document describes the design, the rationale, and the usage
+of the official DLL build of zlib, named ZLIB1.DLL.  If you have
+general questions about zlib, you should see the file "FAQ" found
+in the zlib distribution, or at the following location:
+  http://www.gzip.org/zlib/zlib_faq.html
+
+
+ 1. What is ZLIB1.DLL, and how can I get it?
+
+  - ZLIB1.DLL is the official build of zlib as a DLL.
+    (Please remark the character '1' in the name.)
+
+    Pointers to a precompiled ZLIB1.DLL can be found in the zlib
+    web site at:
+      http://www.zlib.org/
+
+    Applications that link to ZLIB1.DLL can rely on the following
+    specification:
+
+    * The exported symbols are exclusively defined in the source
+      files "zlib.h" and "zlib.def", found in an official zlib
+      source distribution.
+    * The symbols are exported by name, not by ordinal.
+    * The exported names are undecorated.
+    * The calling convention of functions is "C" (CDECL).
+    * The ZLIB1.DLL binary is linked to MSVCRT.DLL.
+
+    The archive in which ZLIB1.DLL is bundled contains compiled
+    test programs that must run with a valid build of ZLIB1.DLL.
+    It is recommended to download the prebuilt DLL from the zlib
+    web site, instead of building it yourself, to avoid potential
+    incompatibilities that could be introduced by your compiler
+    and build settings.  If you do build the DLL yourself, please
+    make sure that it complies with all the above requirements,
+    and it runs with the precompiled test programs, bundled with
+    the original ZLIB1.DLL distribution.
+
+    If, for any reason, you need to build an incompatible DLL,
+    please use a different file name.
+
+
+ 2. Why did you change the name of the DLL to ZLIB1.DLL?
+    What happened to the old ZLIB.DLL?
+
+  - The old ZLIB.DLL, built from zlib-1.1.4 or earlier, required
+    compilation settings that were incompatible to those used by
+    a static build.  The DLL settings were supposed to be enabled
+    by defining the macro ZLIB_DLL, before including "zlib.h".
+    Incorrect handling of this macro was silently accepted at
+    build time, resulting in two major problems:
+
+    * ZLIB_DLL was missing from the old makefile.  When building
+      the DLL, not all people added it to the build options.  In
+      consequence, incompatible incarnations of ZLIB.DLL started
+      to circulate around the net.
+
+    * When switching from using the static library to using the
+      DLL, applications had to define the ZLIB_DLL macro and
+      to recompile all the sources that contained calls to zlib
+      functions.  Failure to do so resulted in creating binaries
+      that were unable to run with the official ZLIB.DLL build.
+
+    The only possible solution that we could foresee was to make
+    a binary-incompatible change in the DLL interface, in order to
+    remove the dependency on the ZLIB_DLL macro, and to release
+    the new DLL under a different name.
+
+    We chose the name ZLIB1.DLL, where '1' indicates the major
+    zlib version number.  We hope that we will not have to break
+    the binary compatibility again, at least not as long as the
+    zlib-1.x series will last.
+
+    There is still a ZLIB_DLL macro, that can trigger a more
+    efficient build and use of the DLL, but compatibility no
+    longer dependents on it.
+
+
+ 3. Can I build ZLIB.DLL from the new zlib sources, and replace
+    an old ZLIB.DLL, that was built from zlib-1.1.4 or earlier?
+
+  - In principle, you can do it by assigning calling convention
+    keywords to the macros ZEXPORT and ZEXPORTVA.  In practice,
+    it depends on what you mean by "an old ZLIB.DLL", because the
+    old DLL exists in several mutually-incompatible versions.
+    You have to find out first what kind of calling convention is
+    being used in your particular ZLIB.DLL build, and to use the
+    same one in the new build.  If you don't know what this is all
+    about, you might be better off if you would just leave the old
+    DLL intact.
+
+
+ 4. Can I compile my application using the new zlib interface, and
+    link it to an old ZLIB.DLL, that was built from zlib-1.1.4 or
+    earlier?
+
+  - The official answer is "no"; the real answer depends again on
+    what kind of ZLIB.DLL you have.  Even if you are lucky, this
+    course of action is unreliable.
+
+    If you rebuild your application and you intend to use a newer
+    version of zlib (post- 1.1.4), it is strongly recommended to
+    link it to the new ZLIB1.DLL.
+
+
+ 5. Why are the zlib symbols exported by name, and not by ordinal?
+
+  - Although exporting symbols by ordinal is a little faster, it
+    is risky.  Any single glitch in the maintenance or use of the
+    DEF file that contains the ordinals can result in incompatible
+    builds and frustrating crashes.  Simply put, the benefits of
+    exporting symbols by ordinal do not justify the risks.
+
+    Technically, it should be possible to maintain ordinals in
+    the DEF file, and still export the symbols by name.  Ordinals
+    exist in every DLL, and even if the dynamic linking performed
+    at the DLL startup is searching for names, ordinals serve as
+    hints, for a faster name lookup.  However, if the DEF file
+    contains ordinals, the Microsoft linker automatically builds
+    an implib that will cause the executables linked to it to use
+    those ordinals, and not the names.  It is interesting to
+    notice that the GNU linker for Win32 does not suffer from this
+    problem.
+
+    It is possible to avoid the DEF file if the exported symbols
+    are accompanied by a "__declspec(dllexport)" attribute in the
+    source files.  You can do this in zlib by predefining the
+    ZLIB_DLL macro.
+
+
+ 6. I see that the ZLIB1.DLL functions use the "C" (CDECL) calling
+    convention.  Why not use the STDCALL convention?
+    STDCALL is the standard convention in Win32, and I need it in
+    my Visual Basic project!
+
+    (For readability, we use CDECL to refer to the convention
+     triggered by the "__cdecl" keyword, STDCALL to refer to
+     the convention triggered by "__stdcall", and FASTCALL to
+     refer to the convention triggered by "__fastcall".)
+
+  - Most of the native Windows API functions (without varargs) use
+    indeed the WINAPI convention (which translates to STDCALL in
+    Win32), but the standard C functions use CDECL.  If a user
+    application is intrinsically tied to the Windows API (e.g.
+    it calls native Windows API functions such as CreateFile()),
+    sometimes it makes sense to decorate its own functions with
+    WINAPI.  But if ANSI C or POSIX portability is a goal (e.g.
+    it calls standard C functions such as fopen()), it is not a
+    sound decision to request the inclusion of <windows.h>, or to
+    use non-ANSI constructs, for the sole purpose to make the user
+    functions STDCALL-able.
+
+    The functionality offered by zlib is not in the category of
+    "Windows functionality", but is more like "C functionality".
+
+    Technically, STDCALL is not bad; in fact, it is slightly
+    faster than CDECL, and it works with variable-argument
+    functions, just like CDECL.  It is unfortunate that, in spite
+    of using STDCALL in the Windows API, it is not the default
+    convention used by the C compilers that run under Windows.
+    The roots of the problem reside deep inside the unsafety of
+    the K&R-style function prototypes, where the argument types
+    are not specified; but that is another story for another day.
+
+    The remaining fact is that CDECL is the default convention.
+    Even if an explicit convention is hard-coded into the function
+    prototypes inside C headers, problems may appear.  The
+    necessity to expose the convention in users' callbacks is one
+    of these problems.
+
+    The calling convention issues are also important when using
+    zlib in other programming languages.  Some of them, like Ada
+    (GNAT) and Fortran (GNU G77), have C bindings implemented
+    initially on Unix, and relying on the C calling convention.
+    On the other hand, the pre- .NET versions of Microsoft Visual
+    Basic require STDCALL, while Borland Delphi prefers, although
+    it does not require, FASTCALL.
+
+    In fairness to all possible uses of zlib outside the C
+    programming language, we choose the default "C" convention.
+    Anyone interested in different bindings or conventions is
+    encouraged to maintain specialized projects.  The "contrib/"
+    directory from the zlib distribution already holds a couple
+    of foreign bindings, such as Ada, C++, and Delphi.
+
+
+ 7. I need a DLL for my Visual Basic project.  What can I do?
+
+  - Define the ZLIB_WINAPI macro before including "zlib.h", when
+    building both the DLL and the user application (except that
+    you don't need to define anything when using the DLL in Visual
+    Basic).  The ZLIB_WINAPI macro will switch on the WINAPI
+    (STDCALL) convention.  The name of this DLL must be different
+    than the official ZLIB1.DLL.
+
+    Gilles Vollant has contributed a build named ZLIBWAPI.DLL,
+    with the ZLIB_WINAPI macro turned on, and with the minizip
+    functionality built in.  For more information, please read
+    the notes inside "contrib/vstudio/readme.txt", found in the
+    zlib distribution.
+
+
+ 8. I need to use zlib in my Microsoft .NET project.  What can I
+    do?
+
+  - Henrik Ravn has contributed a .NET wrapper around zlib.  Look
+    into contrib/dotzlib/, inside the zlib distribution.
+
+
+ 9. If my application uses ZLIB1.DLL, should I link it to
+    MSVCRT.DLL?  Why?
+
+  - It is not required, but it is recommended to link your
+    application to MSVCRT.DLL, if it uses ZLIB1.DLL.
+
+    The executables (.EXE, .DLL, etc.) that are involved in the
+    same process and are using the C run-time library (i.e. they
+    are calling standard C functions), must link to the same
+    library.  There are several libraries in the Win32 system:
+    CRTDLL.DLL, MSVCRT.DLL, the static C libraries, etc.
+    Since ZLIB1.DLL is linked to MSVCRT.DLL, the executables that
+    depend on it should also be linked to MSVCRT.DLL.
+
+
+10. Why are you saying that ZLIB1.DLL and my application should
+    be linked to the same C run-time (CRT) library?  I linked my
+    application and my DLLs to different C libraries (e.g. my
+    application to a static library, and my DLLs to MSVCRT.DLL),
+    and everything works fine.
+
+  - If a user library invokes only pure Win32 API (accessible via
+    <windows.h> and the related headers), its DLL build will work
+    in any context.  But if this library invokes standard C API,
+    things get more complicated.
+
+    There is a single Win32 library in a Win32 system.  Every
+    function in this library resides in a single DLL module, that
+    is safe to call from anywhere.  On the other hand, there are
+    multiple versions of the C library, and each of them has its
+    own separate internal state.  Standalone executables and user
+    DLLs that call standard C functions must link to a C run-time
+    (CRT) library, be it static or shared (DLL).  Intermixing
+    occurs when an executable (not necessarily standalone) and a
+    DLL are linked to different CRTs, and both are running in the
+    same process.
+
+    Intermixing multiple CRTs is possible, as long as their
+    internal states are kept intact.  The Microsoft Knowledge Base
+    articles KB94248 "HOWTO: Use the C Run-Time" and KB140584
+    "HOWTO: Link with the Correct C Run-Time (CRT) Library"
+    mention the potential problems raised by intermixing.
+
+    If intermixing works for you, it's because your application
+    and DLLs are avoiding the corruption of each of the CRTs'
+    internal states, maybe by careful design, or maybe by fortune.
+
+    Also note that linking ZLIB1.DLL to non-Microsoft CRTs, such
+    as those provided by Borland, raises similar problems.
+
+
+11. Why are you linking ZLIB1.DLL to MSVCRT.DLL?
+
+  - MSVCRT.DLL exists on every Windows 95 with a new service pack
+    installed, or with Microsoft Internet Explorer 4 or later, and
+    on all other Windows 4.x or later (Windows 98, Windows NT 4,
+    or later).  It is freely distributable; if not present in the
+    system, it can be downloaded from Microsoft or from other
+    software provider for free.
+
+    The fact that MSVCRT.DLL does not exist on a virgin Windows 95
+    is not so problematic.  Windows 95 is scarcely found nowadays,
+    Microsoft ended its support a long time ago, and many recent
+    applications from various vendors, including Microsoft, do not
+    even run on it.  Furthermore, no serious user should run
+    Windows 95 without a proper update installed.
+
+
+12. Why are you not linking ZLIB1.DLL to
+    <<my favorite C run-time library>> ?
+
+  - We considered and abandoned the following alternatives:
+
+    * Linking ZLIB1.DLL to a static C library (LIBC.LIB, or
+      LIBCMT.LIB) is not a good option.  People are using the DLL
+      mainly to save disk space.  If you are linking your program
+      to a static C library, you may as well consider linking zlib
+      in statically, too.
+
+    * Linking ZLIB1.DLL to CRTDLL.DLL looks appealing, because
+      CRTDLL.DLL is present on every Win32 installation.
+      Unfortunately, it has a series of problems: it does not
+      work properly with Microsoft's C++ libraries, it does not
+      provide support for 64-bit file offsets, (and so on...),
+      and Microsoft discontinued its support a long time ago.
+
+    * Linking ZLIB1.DLL to MSVCR70.DLL or MSVCR71.DLL, supplied
+      with the Microsoft .NET platform, and Visual C++ 7.0/7.1,
+      raises problems related to the status of ZLIB1.DLL as a
+      system component.  According to the Microsoft Knowledge Base
+      article KB326922 "INFO: Redistribution of the Shared C
+      Runtime Component in Visual C++ .NET", MSVCR70.DLL and
+      MSVCR71.DLL are not supposed to function as system DLLs,
+      because they may clash with MSVCRT.DLL.  Instead, the
+      application's installer is supposed to put these DLLs
+      (if needed) in the application's private directory.
+      If ZLIB1.DLL depends on a non-system runtime, it cannot
+      function as a redistributable system component.
+
+    * Linking ZLIB1.DLL to non-Microsoft runtimes, such as
+      Borland's, or Cygwin's, raises problems related to the
+      reliable presence of these runtimes on Win32 systems.
+      It's easier to let the DLL build of zlib up to the people
+      who distribute these runtimes, and who may proceed as
+      explained in the answer to Question 14.
+
+
+13. If ZLIB1.DLL cannot be linked to MSVCR70.DLL or MSVCR71.DLL,
+    how can I build/use ZLIB1.DLL in Microsoft Visual C++ 7.0
+    (Visual Studio .NET) or newer?
+
+  - Due to the problems explained in the Microsoft Knowledge Base
+    article KB326922 (see the previous answer), the C runtime that
+    comes with the VC7 environment is no longer considered a
+    system component.  That is, it should not be assumed that this
+    runtime exists, or may be installed in a system directory.
+    Since ZLIB1.DLL is supposed to be a system component, it may
+    not depend on a non-system component.
+
+    In order to link ZLIB1.DLL and your application to MSVCRT.DLL
+    in VC7, you need the library of Visual C++ 6.0 or older.  If
+    you don't have this library at hand, it's probably best not to
+    use ZLIB1.DLL.
+
+    We are hoping that, in the future, Microsoft will provide a
+    way to build applications linked to a proper system runtime,
+    from the Visual C++ environment.  Until then, you have a
+    couple of alternatives, such as linking zlib in statically.
+    If your application requires dynamic linking, you may proceed
+    as explained in the answer to Question 14.
+
+
+14. I need to link my own DLL build to a CRT different than
+    MSVCRT.DLL.  What can I do?
+
+  - Feel free to rebuild the DLL from the zlib sources, and link
+    it the way you want.  You should, however, clearly state that
+    your build is unofficial.  You should give it a different file
+    name, and/or install it in a private directory that can be
+    accessed by your application only, and is not visible to the
+    others (e.g. it's not in the SYSTEM or the SYSTEM32 directory,
+    and it's not in the PATH).  Otherwise, your build may clash
+    with applications that link to the official build.
+
+    For example, in Cygwin, zlib is linked to the Cygwin runtime
+    CYGWIN1.DLL, and it is distributed under the name CYGZ.DLL.
+
+
+15. May I include additional pieces of code that I find useful,
+    link them in ZLIB1.DLL, and export them?
+
+  - No.  A legitimate build of ZLIB1.DLL must not include code
+    that does not originate from the official zlib source code.
+    But you can make your own private DLL build, under a different
+    file name, as suggested in the previous answer.
+
+    For example, zlib is a part of the VCL library, distributed
+    with Borland Delphi and C++ Builder.  The DLL build of VCL
+    is a redistributable file, named VCLxx.DLL.
+
+
+16. May I remove some functionality out of ZLIB1.DLL, by enabling
+    macros like NO_GZCOMPRESS or NO_GZIP at compile time?
+
+  - No.  A legitimate build of ZLIB1.DLL must provide the complete
+    zlib functionality, as implemented in the official zlib source
+    code.  But you can make your own private DLL build, under a
+    different file name, as suggested in the previous answer.
+
+
+17. I made my own ZLIB1.DLL build.  Can I test it for compliance?
+
+  - We prefer that you download the official DLL from the zlib
+    web site.  If you need something peculiar from this DLL, you
+    can send your suggestion to the zlib mailing list.
+
+    However, in case you do rebuild the DLL yourself, you can run
+    it with the test programs found in the DLL distribution.
+    Running these test programs is not a guarantee of compliance,
+    but a failure can imply a detected problem.
+
+**
+
+This document is written and maintained by
+Cosmin Truta <cosmint@cs.ubbcluj.ro>
diff --git a/gs/zlib/win32/Makefile.bor b/gs/zlib/win32/Makefile.bor
new file mode 100644
index 000000000..b802519ca
--- /dev/null
+++ b/gs/zlib/win32/Makefile.bor
@@ -0,0 +1,107 @@
+# Makefile for zlib
+# Borland C++ for Win32
+#
+# Updated for zlib 1.2.x by Cosmin Truta, 11-Mar-2003
+# Last updated: 28-Aug-2003
+#
+# Usage:
+#  make -f win32/Makefile.bor
+#  make -f win32/Makefile.bor LOCAL_ZLIB=-DASMV OBJA=match.obj OBJPA=+match.obj
+
+# ------------ Borland C++ ------------
+
+# Optional nonstandard preprocessor flags (e.g. -DMAX_MEM_LEVEL=7)
+# should be added to the environment via "set LOCAL_ZLIB=-DFOO" or
+# added to the declaration of LOC here:
+LOC = $(LOCAL_ZLIB)
+
+CC = bcc32
+AS = bcc32
+LD = bcc32
+AR = tlib
+CFLAGS  = -a -d -k- -O2 $(LOC)
+ASFLAGS = $(LOC)
+LDFLAGS = $(LOC)
+
+
+# variables
+ZLIB_LIB = zlib.lib
+
+OBJ1  = adler32.obj compress.obj crc32.obj deflate.obj gzio.obj infback.obj
+OBJ2  = inffast.obj inflate.obj inftrees.obj trees.obj uncompr.obj zutil.obj
+#OBJA =
+OBJP1 = +adler32.obj+compress.obj+crc32.obj+deflate.obj+gzio.obj+infback.obj
+OBJP2 = +inffast.obj+inflate.obj+inftrees.obj+trees.obj+uncompr.obj+zutil.obj
+#OBJPA=
+
+
+# targets
+all: $(ZLIB_LIB) example.exe minigzip.exe
+
+.c.obj:
+	$(CC) -c $(CFLAGS) $<
+
+.asm.obj:
+	$(AS) -c $(ASFLAGS) $<
+
+adler32.obj: adler32.c zlib.h zconf.h
+
+compress.obj: compress.c zlib.h zconf.h
+
+crc32.obj: crc32.c zlib.h zconf.h crc32.h
+
+deflate.obj: deflate.c deflate.h zutil.h zlib.h zconf.h
+
+gzio.obj: gzio.c zutil.h zlib.h zconf.h
+
+infback.obj: infback.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inffast.obj: inffast.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h
+
+inflate.obj: inflate.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+ inffast.h inffixed.h
+
+inftrees.obj: inftrees.c zutil.h zlib.h zconf.h inftrees.h
+
+trees.obj: trees.c zutil.h zlib.h zconf.h deflate.h trees.h
+
+uncompr.obj: uncompr.c zlib.h zconf.h
+
+zutil.obj: zutil.c zutil.h zlib.h zconf.h
+
+example.obj: example.c zlib.h zconf.h
+
+minigzip.obj: minigzip.c zlib.h zconf.h
+
+
+# For the sake of the old Borland make,
+# the command line is cut to fit in the MS-DOS 128 byte limit:
+$(ZLIB_LIB): $(OBJ1) $(OBJ2) $(OBJA)
+	-del $(ZLIB_LIB)
+	$(AR) $(ZLIB_LIB) $(OBJP1)
+	$(AR) $(ZLIB_LIB) $(OBJP2)
+	$(AR) $(ZLIB_LIB) $(OBJPA)
+
+
+# testing
+test: example.exe minigzip.exe
+	example
+	echo hello world | minigzip | minigzip -d
+
+example.exe: example.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) example.obj $(ZLIB_LIB)
+
+minigzip.exe: minigzip.obj $(ZLIB_LIB)
+	$(LD) $(LDFLAGS) minigzip.obj $(ZLIB_LIB)
+
+
+# cleanup
+clean:
+	-del *.obj
+	-del *.lib
+	-del *.exe
+	-del *.tds
+	-del zlib.bak
+	-del foo.gz
diff --git a/gs/zlib/win32/Makefile.emx b/gs/zlib/win32/Makefile.emx
new file mode 100644
index 000000000..7b08424ce
--- /dev/null
+++ b/gs/zlib/win32/Makefile.emx
@@ -0,0 +1,69 @@
+# Makefile for zlib.  Modified for emx/rsxnt by Chr. Spieler, 6/16/98.
+# Copyright (C) 1995-1998 Jean-loup Gailly.
+# For conditions of distribution and use, see copyright notice in zlib.h
+
+# To compile, or to compile and test, type:
+#
+#   make -fmakefile.emx;  make test -fmakefile.emx
+#
+
+CC=gcc -Zwin32
+
+#CFLAGS=-MMD -O
+#CFLAGS=-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7
+#CFLAGS=-MMD -g -DDEBUG
+CFLAGS=-MMD -O3 $(BUTT) -Wall -Wwrite-strings -Wpointer-arith -Wconversion \
+             -Wstrict-prototypes -Wmissing-prototypes
+
+# If cp.exe is available, replace "copy /Y" with "cp -fp" .
+CP=copy /Y
+# If gnu install.exe is available, replace $(CP) with ginstall.
+INSTALL=$(CP)
+# The default value of RM is "rm -f."  If "rm.exe" is found, comment out:
+RM=del
+LDLIBS=-L. -lzlib
+LD=$(CC) -s -o
+LDSHARED=$(CC)
+
+INCL=zlib.h zconf.h
+LIBS=zlib.a
+
+AR=ar rcs
+
+prefix=/usr/local
+exec_prefix = $(prefix)
+
+OBJS = adler32.o compress.o crc32.o gzio.o uncompr.o deflate.o trees.o \
+       zutil.o inflate.o infback.o inftrees.o inffast.o
+
+TEST_OBJS = example.o minigzip.o
+
+all: example.exe minigzip.exe
+
+test: all
+	./example
+	echo hello world | .\minigzip | .\minigzip -d
+
+%.o : %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+zlib.a: $(OBJS)
+	$(AR) $@ $(OBJS)
+
+%.exe : %.o $(LIBS)
+	$(LD) $@ $< $(LDLIBS)
+
+
+.PHONY : clean
+
+clean:
+	$(RM) *.d
+	$(RM) *.o
+	$(RM) *.exe
+	$(RM) zlib.a
+	$(RM) foo.gz
+
+DEPS := $(wildcard *.d)
+ifneq ($(DEPS),)
+include $(DEPS)
+endif
diff --git a/gs/zlib/win32/Makefile.gcc b/gs/zlib/win32/Makefile.gcc
new file mode 100644
index 000000000..62a843015
--- /dev/null
+++ b/gs/zlib/win32/Makefile.gcc
@@ -0,0 +1,141 @@
+# Makefile for zlib, derived from Makefile.dj2.
+# Modified for mingw32 by C. Spieler, 6/16/98.
+# Updated for zlib 1.2.x by Christian Spieler and Cosmin Truta, Mar-2003.
+# Last updated: 1-Aug-2003.
+# Tested under Cygwin and MinGW.
+
+# Copyright (C) 1995-2003 Jean-loup Gailly.
+# For conditions of distribution and use, see copyright notice in zlib.h
+
+# To compile, or to compile and test, type:
+#
+#   make -fmakefile.gcc;  make test testdll -fmakefile.gcc
+#
+# To use the asm code, type:
+#   cp contrib/asm?86/match.S ./match.S
+#   make LOC=-DASMV OBJA=match.o -fmakefile.gcc
+#
+# To install libz.a, zconf.h and zlib.h in the system directories, type:
+#
+#   make install -fmakefile.gcc
+
+# Note:
+# If the platform is *not* MinGW (e.g. it is Cygwin or UWIN),
+# the DLL name should be changed from "zlib1.dll".
+
+STATICLIB = libz.a
+SHAREDLIB = zlib1.dll
+IMPLIB    = libzdll.a
+
+#LOC = -DASMV
+#LOC = -DDEBUG -g
+
+CC = gcc
+CFLAGS = $(LOC) -O3 -Wall
+
+AS = $(CC)
+ASFLAGS = $(LOC) -Wall
+
+LD = $(CC)
+LDFLAGS = $(LOC) -s
+
+AR = ar
+ARFLAGS = rcs
+
+RC = windres
+RCFLAGS = --define GCC_WINDRES
+
+CP = cp -fp
+# If GNU install is available, replace $(CP) with install.
+INSTALL = $(CP)
+RM = rm -f
+
+prefix = /usr/local
+exec_prefix = $(prefix)
+
+OBJS = adler32.o compress.o crc32.o deflate.o gzio.o infback.o \
+       inffast.o inflate.o inftrees.o trees.o uncompr.o zutil.o
+OBJA =
+
+all: $(STATICLIB) $(SHAREDLIB) $(IMPLIB) example minigzip example_d minigzip_d
+
+test: example minigzip
+	./example
+	echo hello world | ./minigzip | ./minigzip -d
+
+testdll: example_d minigzip_d
+	./example_d
+	echo hello world | ./minigzip_d | ./minigzip_d -d
+
+.c.o:
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+.S.o:
+	$(AS) $(ASFLAGS) -c -o $@ $<
+
+$(STATICLIB): $(OBJS) $(OBJA)
+	$(AR) $(ARFLAGS) $@ $(OBJS) $(OBJA)
+
+$(IMPLIB): $(SHAREDLIB)
+
+$(SHAREDLIB): win32/zlib.def $(OBJS) $(OBJA) zlibrc.o
+	dllwrap --driver-name $(CC) --def win32/zlib.def \
+	  --implib $(IMPLIB) -o $@ $(OBJS) $(OBJA) zlibrc.o
+	strip $@
+
+example: example.o $(STATICLIB)
+	$(LD) $(LDFLAGS) -o $@ example.o $(STATICLIB)
+
+minigzip: minigzip.o $(STATICLIB)
+	$(LD) $(LDFLAGS) -o $@ minigzip.o $(STATICLIB)
+
+example_d: example.o $(IMPLIB)
+	$(LD) $(LDFLAGS) -o $@ example.o $(IMPLIB)
+
+minigzip_d: minigzip.o $(IMPLIB)
+	$(LD) $(LDFLAGS) -o $@ minigzip.o $(IMPLIB)
+
+zlibrc.o: win32/zlib1.rc
+	$(RC) $(RCFLAGS) -o $@ win32/zlib1.rc
+
+
+# INCLUDE_PATH and LIBRARY_PATH must be set.
+
+.PHONY: install uninstall clean
+
+install: zlib.h zconf.h $(LIB)
+	-@if not exist $(INCLUDE_PATH)/nul mkdir $(INCLUDE_PATH)
+	-@if not exist $(LIBRARY_PATH)/nul mkdir $(LIBRARY_PATH)
+	-$(INSTALL) zlib.h $(INCLUDE_PATH)
+	-$(INSTALL) zconf.h $(INCLUDE_PATH)
+	-$(INSTALL) $(STATICLIB) $(LIBRARY_PATH)
+	-$(INSTALL) $(IMPLIB) $(LIBRARY_PATH)
+
+uninstall:
+	-$(RM) $(INCLUDE_PATH)/zlib.h
+	-$(RM) $(INCLUDE_PATH)/zconf.h
+	-$(RM) $(LIBRARY_PATH)/$(STATICLIB)
+	-$(RM) $(LIBRARY_PATH)/$(IMPLIB)
+
+clean:
+	-$(RM) $(STATICLIB)
+	-$(RM) $(SHAREDLIB)
+	-$(RM) $(IMPLIB)
+	-$(RM) *.o
+	-$(RM) *.exe
+	-$(RM) foo.gz
+
+adler32.o: zlib.h zconf.h
+compress.o: zlib.h zconf.h
+crc32.o: crc32.h zlib.h zconf.h
+deflate.o: deflate.h zutil.h zlib.h zconf.h
+example.o: zlib.h zconf.h
+gzio.o: zutil.h zlib.h zconf.h
+inffast.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+inflate.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+infback.o: zutil.h zlib.h zconf.h inftrees.h inflate.h inffast.h
+inftrees.o: zutil.h zlib.h zconf.h inftrees.h
+minigzip.o: zlib.h zconf.h
+trees.o: deflate.h zutil.h zlib.h zconf.h trees.h
+uncompr.o: zlib.h zconf.h
+zutil.o: zutil.h zlib.h zconf.h
diff --git a/gs/zlib/win32/Makefile.msc b/gs/zlib/win32/Makefile.msc
new file mode 100644
index 000000000..528ecaaf2
--- /dev/null
+++ b/gs/zlib/win32/Makefile.msc
@@ -0,0 +1,126 @@
+# Makefile for zlib -- Microsoft (Visual) C
+#
+# Authors:
+#   Cosmin Truta, 11-Mar-2003
+#   Christian Spieler, 19-Mar-2003
+#
+# Last updated:
+#   Cosmin Truta, 27-Aug-2003
+#
+# Usage:
+#   nmake -f win32/Makefile.msc            (standard build)
+#   nmake -f win32/Makefile.msc LOC=-DFOO  (nonstandard build)
+#   nmake -f win32/Makefile.msc LOC=-DASMV OBJA=match.obj  (use ASM code)
+
+
+# optional build flags
+LOC =
+
+
+# variables
+STATICLIB = zlib.lib
+SHAREDLIB = zlib1.dll
+IMPLIB    = zdll.lib
+
+CC = cl
+AS = ml
+LD = link
+AR = lib
+RC = rc
+CFLAGS  = -nologo -MD -O2 $(LOC)
+ASFLAGS = -coff
+LDFLAGS = -nologo -release
+ARFLAGS = -nologo
+RCFLAGS = /dWIN32 /r
+
+OBJS = adler32.obj compress.obj crc32.obj deflate.obj gzio.obj infback.obj \
+       inffast.obj inflate.obj inftrees.obj trees.obj uncompr.obj zutil.obj
+OBJA =
+
+
+# targets
+all: $(STATICLIB) $(SHAREDLIB) $(IMPLIB) \
+     example.exe minigzip.exe example_d.exe minigzip_d.exe
+
+$(STATICLIB): $(OBJS) $(OBJA)
+	$(AR) $(ARFLAGS) -out:$@ $(OBJS) $(OBJA)
+
+$(IMPLIB): $(SHAREDLIB)
+
+$(SHAREDLIB): win32/zlib.def $(OBJS) $(OBJA) zlib1.res
+	$(LD) $(LDFLAGS) -def:win32/zlib.def -dll -implib:$(IMPLIB) \
+	  -out:$@ $(OBJS) $(OBJA) zlib1.res
+
+example.exe: example.obj $(STATICLIB)
+	$(LD) $(LDFLAGS) example.obj $(STATICLIB)
+
+minigzip.exe: minigzip.obj $(STATICLIB)
+	$(LD) $(LDFLAGS) minigzip.obj $(STATICLIB)
+
+example_d.exe: example.obj $(IMPLIB)
+	$(LD) $(LDFLAGS) -out:$@ example.obj $(IMPLIB)
+
+minigzip_d.exe: minigzip.obj $(IMPLIB)
+	$(LD) $(LDFLAGS) -out:$@ minigzip.obj $(IMPLIB)
+
+.c.obj:
+	$(CC) -c $(CFLAGS) $<
+
+.asm.obj:
+	$(AS) -c $(ASFLAGS) $<
+
+adler32.obj: adler32.c zlib.h zconf.h
+
+compress.obj: compress.c zlib.h zconf.h
+
+crc32.obj: crc32.c zlib.h zconf.h crc32.h
+
+deflate.obj: deflate.c deflate.h zutil.h zlib.h zconf.h
+
+gzio.obj: gzio.c zutil.h zlib.h zconf.h
+
+infback.obj: infback.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+             inffast.h inffixed.h
+
+inffast.obj: inffast.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+             inffast.h
+
+inflate.obj: inflate.c zutil.h zlib.h zconf.h inftrees.h inflate.h \
+             inffast.h inffixed.h
+
+inftrees.obj: inftrees.c zutil.h zlib.h zconf.h inftrees.h
+
+trees.obj: trees.c zutil.h zlib.h zconf.h deflate.h trees.h
+
+uncompr.obj: uncompr.c zlib.h zconf.h
+
+zutil.obj: zutil.c zutil.h zlib.h zconf.h
+
+example.obj: example.c zlib.h zconf.h
+
+minigzip.obj: minigzip.c zlib.h zconf.h
+
+zlib1.res: win32/zlib1.rc
+	$(RC) $(RCFLAGS) /fo$@ win32/zlib1.rc
+
+
+# testing
+test: example.exe minigzip.exe
+	example
+	echo hello world | minigzip | minigzip -d
+
+testdll: example_d.exe minigzip_d.exe
+	example_d
+	echo hello world | minigzip_d | minigzip_d -d
+
+
+# cleanup
+clean:
+	-del $(STATICLIB)
+	-del $(SHAREDLIB)
+	-del $(IMPLIB)
+	-del *.obj
+	-del *.res
+	-del *.exp
+	-del *.exe
+	-del foo.gz
diff --git a/gs/zlib/win32/VisualC.txt b/gs/zlib/win32/VisualC.txt
new file mode 100644
index 000000000..579a5fc9e
--- /dev/null
+++ b/gs/zlib/win32/VisualC.txt
@@ -0,0 +1,3 @@
+
+To build zlib using the Microsoft Visual C++ environment,
+use the appropriate project from the projects/ directory.
diff --git a/gs/zlib/win32/zlib.def b/gs/zlib/win32/zlib.def
new file mode 100644
index 000000000..a47cbc10c
--- /dev/null
+++ b/gs/zlib/win32/zlib.def
@@ -0,0 +1,60 @@
+LIBRARY
+; zlib data compression library
+
+EXPORTS
+; basic functions
+    zlibVersion
+    deflate
+    deflateEnd
+    inflate
+    inflateEnd
+; advanced functions
+    deflateSetDictionary
+    deflateCopy
+    deflateReset
+    deflateParams
+    deflateBound
+    deflatePrime
+    inflateSetDictionary
+    inflateSync
+    inflateCopy
+    inflateReset
+    inflateBack
+    inflateBackEnd
+    zlibCompileFlags
+; utility functions
+    compress
+    compress2
+    compressBound
+    uncompress
+    gzopen
+    gzdopen
+    gzsetparams
+    gzread
+    gzwrite
+    gzprintf
+    gzputs
+    gzgets
+    gzputc
+    gzgetc
+    gzungetc
+    gzflush
+    gzseek
+    gzrewind
+    gztell
+    gzeof
+    gzclose
+    gzerror
+    gzclearerr
+; checksum functions
+    adler32
+    crc32
+; various hacks, don't look :)
+    deflateInit_
+    deflateInit2_
+    inflateInit_
+    inflateInit2_
+    inflateBackInit_
+    inflateSyncPoint
+    get_crc_table
+    zError
diff --git a/gs/zlib/win32/zlib1.rc b/gs/zlib/win32/zlib1.rc
new file mode 100644
index 000000000..99025c974
--- /dev/null
+++ b/gs/zlib/win32/zlib1.rc
@@ -0,0 +1,39 @@
+#include <windows.h>
+
+#ifdef GCC_WINDRES
+VS_VERSION_INFO		VERSIONINFO
+#else
+VS_VERSION_INFO		VERSIONINFO	MOVEABLE IMPURE LOADONCALL DISCARDABLE
+#endif
+  FILEVERSION		1,2,2,0
+  PRODUCTVERSION	1,2,2,0
+  FILEFLAGSMASK		VS_FFI_FILEFLAGSMASK
+#ifdef _DEBUG
+  FILEFLAGS		1
+#else
+  FILEFLAGS		0
+#endif
+  FILEOS		VOS_DOS_WINDOWS32
+  FILETYPE		VFT_DLL
+  FILESUBTYPE		0	// not used
+BEGIN
+  BLOCK "StringFileInfo"
+  BEGIN
+    BLOCK "040904E4"
+    //language ID = U.S. English, char set = Windows, Multilingual
+    BEGIN
+      VALUE "FileDescription",	"zlib data compression library\0"
+      VALUE "FileVersion",	"1.2.3\0"
+      VALUE "InternalName",	"zlib1.dll\0"
+      VALUE "LegalCopyright",	"(C) 1995-2004 Jean-loup Gailly & Mark Adler\0"
+      VALUE "OriginalFilename",	"zlib1.dll\0"
+      VALUE "ProductName",	"zlib\0"
+      VALUE "ProductVersion",	"1.2.3\0"
+      VALUE "Comments","DLL support by Alessandro Iacopetti & Gilles Vollant\0"
+    END
+  END
+  BLOCK "VarFileInfo"
+  BEGIN
+    VALUE "Translation", 0x0409, 1252
+  END
+END
diff --git a/gs/zlib/zconf.h b/gs/zlib/zconf.h
new file mode 100644
index 000000000..03a9431c8
--- /dev/null
+++ b/gs/zlib/zconf.h
@@ -0,0 +1,332 @@
+/* zconf.h -- configuration of the zlib compression library
+ * Copyright (C) 1995-2005 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* @(#) $Id$ */
+
+#ifndef ZCONF_H
+#define ZCONF_H
+
+/*
+ * If you *really* need a unique prefix for all types and library functions,
+ * compile with -DZ_PREFIX. The "standard" zlib should be compiled without it.
+ */
+#ifdef Z_PREFIX
+#  define deflateInit_          z_deflateInit_
+#  define deflate               z_deflate
+#  define deflateEnd            z_deflateEnd
+#  define inflateInit_          z_inflateInit_
+#  define inflate               z_inflate
+#  define inflateEnd            z_inflateEnd
+#  define deflateInit2_         z_deflateInit2_
+#  define deflateSetDictionary  z_deflateSetDictionary
+#  define deflateCopy           z_deflateCopy
+#  define deflateReset          z_deflateReset
+#  define deflateParams         z_deflateParams
+#  define deflateBound          z_deflateBound
+#  define deflatePrime          z_deflatePrime
+#  define inflateInit2_         z_inflateInit2_
+#  define inflateSetDictionary  z_inflateSetDictionary
+#  define inflateSync           z_inflateSync
+#  define inflateSyncPoint      z_inflateSyncPoint
+#  define inflateCopy           z_inflateCopy
+#  define inflateReset          z_inflateReset
+#  define inflateBack           z_inflateBack
+#  define inflateBackEnd        z_inflateBackEnd
+#  define compress              z_compress
+#  define compress2             z_compress2
+#  define compressBound         z_compressBound
+#  define uncompress            z_uncompress
+#  define adler32               z_adler32
+#  define crc32                 z_crc32
+#  define get_crc_table         z_get_crc_table
+#  define zError                z_zError
+
+#  define alloc_func            z_alloc_func
+#  define free_func             z_free_func
+#  define in_func               z_in_func
+#  define out_func              z_out_func
+#  define Byte                  z_Byte
+#  define uInt                  z_uInt
+#  define uLong                 z_uLong
+#  define Bytef                 z_Bytef
+#  define charf                 z_charf
+#  define intf                  z_intf
+#  define uIntf                 z_uIntf
+#  define uLongf                z_uLongf
+#  define voidpf                z_voidpf
+#  define voidp                 z_voidp
+#endif
+
+#if defined(__MSDOS__) && !defined(MSDOS)
+#  define MSDOS
+#endif
+#if (defined(OS_2) || defined(__OS2__)) && !defined(OS2)
+#  define OS2
+#endif
+#if defined(_WINDOWS) && !defined(WINDOWS)
+#  define WINDOWS
+#endif
+#if defined(_WIN32) || defined(_WIN32_WCE) || defined(__WIN32__)
+#  ifndef WIN32
+#    define WIN32
+#  endif
+#endif
+#if (defined(MSDOS) || defined(OS2) || defined(WINDOWS)) && !defined(WIN32)
+#  if !defined(__GNUC__) && !defined(__FLAT__) && !defined(__386__)
+#    ifndef SYS16BIT
+#      define SYS16BIT
+#    endif
+#  endif
+#endif
+
+/*
+ * Compile with -DMAXSEG_64K if the alloc function cannot allocate more
+ * than 64k bytes at a time (needed on systems with 16-bit int).
+ */
+#ifdef SYS16BIT
+#  define MAXSEG_64K
+#endif
+#ifdef MSDOS
+#  define UNALIGNED_OK
+#endif
+
+#ifdef __STDC_VERSION__
+#  ifndef STDC
+#    define STDC
+#  endif
+#  if __STDC_VERSION__ >= 199901L
+#    ifndef STDC99
+#      define STDC99
+#    endif
+#  endif
+#endif
+#if !defined(STDC) && (defined(__STDC__) || defined(__cplusplus))
+#  define STDC
+#endif
+#if !defined(STDC) && (defined(__GNUC__) || defined(__BORLANDC__))
+#  define STDC
+#endif
+#if !defined(STDC) && (defined(MSDOS) || defined(WINDOWS) || defined(WIN32))
+#  define STDC
+#endif
+#if !defined(STDC) && (defined(OS2) || defined(__HOS_AIX__))
+#  define STDC
+#endif
+
+#if defined(__OS400__) && !defined(STDC)    /* iSeries (formerly AS/400). */
+#  define STDC
+#endif
+
+#ifndef STDC
+#  ifndef const /* cannot use !defined(STDC) && !defined(const) on Mac */
+#    define const       /* note: need a more gentle solution here */
+#  endif
+#endif
+
+/* Some Mac compilers merge all .h files incorrectly: */
+#if defined(__MWERKS__)||defined(applec)||defined(THINK_C)||defined(__SC__)
+#  define NO_DUMMY_DECL
+#endif
+
+/* Maximum value for memLevel in deflateInit2 */
+#ifndef MAX_MEM_LEVEL
+#  ifdef MAXSEG_64K
+#    define MAX_MEM_LEVEL 8
+#  else
+#    define MAX_MEM_LEVEL 9
+#  endif
+#endif
+
+/* Maximum value for windowBits in deflateInit2 and inflateInit2.
+ * WARNING: reducing MAX_WBITS makes minigzip unable to extract .gz files
+ * created by gzip. (Files created by minigzip can still be extracted by
+ * gzip.)
+ */
+#ifndef MAX_WBITS
+#  define MAX_WBITS   15 /* 32K LZ77 window */
+#endif
+
+/* The memory requirements for deflate are (in bytes):
+            (1 << (windowBits+2)) +  (1 << (memLevel+9))
+ that is: 128K for windowBits=15  +  128K for memLevel = 8  (default values)
+ plus a few kilobytes for small objects. For example, if you want to reduce
+ the default memory requirements from 256K to 128K, compile with
+     make CFLAGS="-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7"
+ Of course this will generally degrade compression (there's no free lunch).
+
+   The memory requirements for inflate are (in bytes) 1 << windowBits
+ that is, 32K for windowBits=15 (default value) plus a few kilobytes
+ for small objects.
+*/
+
+                        /* Type declarations */
+
+#ifndef OF /* function prototypes */
+#  ifdef STDC
+#    define OF(args)  args
+#  else
+#    define OF(args)  ()
+#  endif
+#endif
+
+/* The following definitions for FAR are needed only for MSDOS mixed
+ * model programming (small or medium model with some far allocations).
+ * This was tested only with MSC; for other MSDOS compilers you may have
+ * to define NO_MEMCPY in zutil.h.  If you don't need the mixed model,
+ * just define FAR to be empty.
+ */
+#ifdef SYS16BIT
+#  if defined(M_I86SM) || defined(M_I86MM)
+     /* MSC small or medium model */
+#    define SMALL_MEDIUM
+#    ifdef _MSC_VER
+#      define FAR _far
+#    else
+#      define FAR far
+#    endif
+#  endif
+#  if (defined(__SMALL__) || defined(__MEDIUM__))
+     /* Turbo C small or medium model */
+#    define SMALL_MEDIUM
+#    ifdef __BORLANDC__
+#      define FAR _far
+#    else
+#      define FAR far
+#    endif
+#  endif
+#endif
+
+#if defined(WINDOWS) || defined(WIN32)
+   /* If building or using zlib as a DLL, define ZLIB_DLL.
+    * This is not mandatory, but it offers a little performance increase.
+    */
+#  ifdef ZLIB_DLL
+#    if defined(WIN32) && (!defined(__BORLANDC__) || (__BORLANDC__ >= 0x500))
+#      ifdef ZLIB_INTERNAL
+#        define ZEXTERN extern __declspec(dllexport)
+#      else
+#        define ZEXTERN extern __declspec(dllimport)
+#      endif
+#    endif
+#  endif  /* ZLIB_DLL */
+   /* If building or using zlib with the WINAPI/WINAPIV calling convention,
+    * define ZLIB_WINAPI.
+    * Caution: the standard ZLIB1.DLL is NOT compiled using ZLIB_WINAPI.
+    */
+#  ifdef ZLIB_WINAPI
+#    ifdef FAR
+#      undef FAR
+#    endif
+#    include <windows.h>
+     /* No need for _export, use ZLIB.DEF instead. */
+     /* For complete Windows compatibility, use WINAPI, not __stdcall. */
+#    define ZEXPORT WINAPI
+#    ifdef WIN32
+#      define ZEXPORTVA WINAPIV
+#    else
+#      define ZEXPORTVA FAR CDECL
+#    endif
+#  endif
+#endif
+
+#if defined (__BEOS__)
+#  ifdef ZLIB_DLL
+#    ifdef ZLIB_INTERNAL
+#      define ZEXPORT   __declspec(dllexport)
+#      define ZEXPORTVA __declspec(dllexport)
+#    else
+#      define ZEXPORT   __declspec(dllimport)
+#      define ZEXPORTVA __declspec(dllimport)
+#    endif
+#  endif
+#endif
+
+#ifndef ZEXTERN
+#  define ZEXTERN extern
+#endif
+#ifndef ZEXPORT
+#  define ZEXPORT
+#endif
+#ifndef ZEXPORTVA
+#  define ZEXPORTVA
+#endif
+
+#ifndef FAR
+#  define FAR
+#endif
+
+#if !defined(__MACTYPES__)
+typedef unsigned char  Byte;  /* 8 bits */
+#endif
+typedef unsigned int   uInt;  /* 16 bits or more */
+typedef unsigned long  uLong; /* 32 bits or more */
+
+#ifdef SMALL_MEDIUM
+   /* Borland C/C++ and some old MSC versions ignore FAR inside typedef */
+#  define Bytef Byte FAR
+#else
+   typedef Byte  FAR Bytef;
+#endif
+typedef char  FAR charf;
+typedef int   FAR intf;
+typedef uInt  FAR uIntf;
+typedef uLong FAR uLongf;
+
+#ifdef STDC
+   typedef void const *voidpc;
+   typedef void FAR   *voidpf;
+   typedef void       *voidp;
+#else
+   typedef Byte const *voidpc;
+   typedef Byte FAR   *voidpf;
+   typedef Byte       *voidp;
+#endif
+
+#if 0           /* HAVE_UNISTD_H -- this line is updated by ./configure */
+#  include <sys/types.h> /* for off_t */
+#  include <unistd.h>    /* for SEEK_* and off_t */
+#  ifdef VMS
+#    include <unixio.h>   /* for off_t */
+#  endif
+#  define z_off_t off_t
+#endif
+#ifndef SEEK_SET
+#  define SEEK_SET        0       /* Seek from beginning of file.  */
+#  define SEEK_CUR        1       /* Seek from current position.  */
+#  define SEEK_END        2       /* Set file pointer to EOF plus "offset" */
+#endif
+#ifndef z_off_t
+#  define z_off_t long
+#endif
+
+#if defined(__OS400__)
+#  define NO_vsnprintf
+#endif
+
+#if defined(__MVS__)
+#  define NO_vsnprintf
+#  ifdef FAR
+#    undef FAR
+#  endif
+#endif
+
+/* MVS linker does not support external names larger than 8 bytes */
+#if defined(__MVS__)
+#   pragma map(deflateInit_,"DEIN")
+#   pragma map(deflateInit2_,"DEIN2")
+#   pragma map(deflateEnd,"DEEND")
+#   pragma map(deflateBound,"DEBND")
+#   pragma map(inflateInit_,"ININ")
+#   pragma map(inflateInit2_,"ININ2")
+#   pragma map(inflateEnd,"INEND")
+#   pragma map(inflateSync,"INSY")
+#   pragma map(inflateSetDictionary,"INSEDI")
+#   pragma map(compressBound,"CMBND")
+#   pragma map(inflate_table,"INTABL")
+#   pragma map(inflate_fast,"INFA")
+#   pragma map(inflate_copyright,"INCOPY")
+#endif
+
+#endif /* ZCONF_H */
diff --git a/gs/zlib/zconf.in.h b/gs/zlib/zconf.in.h
new file mode 100644
index 000000000..03a9431c8
--- /dev/null
+++ b/gs/zlib/zconf.in.h
@@ -0,0 +1,332 @@
+/* zconf.h -- configuration of the zlib compression library
+ * Copyright (C) 1995-2005 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* @(#) $Id$ */
+
+#ifndef ZCONF_H
+#define ZCONF_H
+
+/*
+ * If you *really* need a unique prefix for all types and library functions,
+ * compile with -DZ_PREFIX. The "standard" zlib should be compiled without it.
+ */
+#ifdef Z_PREFIX
+#  define deflateInit_          z_deflateInit_
+#  define deflate               z_deflate
+#  define deflateEnd            z_deflateEnd
+#  define inflateInit_          z_inflateInit_
+#  define inflate               z_inflate
+#  define inflateEnd            z_inflateEnd
+#  define deflateInit2_         z_deflateInit2_
+#  define deflateSetDictionary  z_deflateSetDictionary
+#  define deflateCopy           z_deflateCopy
+#  define deflateReset          z_deflateReset
+#  define deflateParams         z_deflateParams
+#  define deflateBound          z_deflateBound
+#  define deflatePrime          z_deflatePrime
+#  define inflateInit2_         z_inflateInit2_
+#  define inflateSetDictionary  z_inflateSetDictionary
+#  define inflateSync           z_inflateSync
+#  define inflateSyncPoint      z_inflateSyncPoint
+#  define inflateCopy           z_inflateCopy
+#  define inflateReset          z_inflateReset
+#  define inflateBack           z_inflateBack
+#  define inflateBackEnd        z_inflateBackEnd
+#  define compress              z_compress
+#  define compress2             z_compress2
+#  define compressBound         z_compressBound
+#  define uncompress            z_uncompress
+#  define adler32               z_adler32
+#  define crc32                 z_crc32
+#  define get_crc_table         z_get_crc_table
+#  define zError                z_zError
+
+#  define alloc_func            z_alloc_func
+#  define free_func             z_free_func
+#  define in_func               z_in_func
+#  define out_func              z_out_func
+#  define Byte                  z_Byte
+#  define uInt                  z_uInt
+#  define uLong                 z_uLong
+#  define Bytef                 z_Bytef
+#  define charf                 z_charf
+#  define intf                  z_intf
+#  define uIntf                 z_uIntf
+#  define uLongf                z_uLongf
+#  define voidpf                z_voidpf
+#  define voidp                 z_voidp
+#endif
+
+#if defined(__MSDOS__) && !defined(MSDOS)
+#  define MSDOS
+#endif
+#if (defined(OS_2) || defined(__OS2__)) && !defined(OS2)
+#  define OS2
+#endif
+#if defined(_WINDOWS) && !defined(WINDOWS)
+#  define WINDOWS
+#endif
+#if defined(_WIN32) || defined(_WIN32_WCE) || defined(__WIN32__)
+#  ifndef WIN32
+#    define WIN32
+#  endif
+#endif
+#if (defined(MSDOS) || defined(OS2) || defined(WINDOWS)) && !defined(WIN32)
+#  if !defined(__GNUC__) && !defined(__FLAT__) && !defined(__386__)
+#    ifndef SYS16BIT
+#      define SYS16BIT
+#    endif
+#  endif
+#endif
+
+/*
+ * Compile with -DMAXSEG_64K if the alloc function cannot allocate more
+ * than 64k bytes at a time (needed on systems with 16-bit int).
+ */
+#ifdef SYS16BIT
+#  define MAXSEG_64K
+#endif
+#ifdef MSDOS
+#  define UNALIGNED_OK
+#endif
+
+#ifdef __STDC_VERSION__
+#  ifndef STDC
+#    define STDC
+#  endif
+#  if __STDC_VERSION__ >= 199901L
+#    ifndef STDC99
+#      define STDC99
+#    endif
+#  endif
+#endif
+#if !defined(STDC) && (defined(__STDC__) || defined(__cplusplus))
+#  define STDC
+#endif
+#if !defined(STDC) && (defined(__GNUC__) || defined(__BORLANDC__))
+#  define STDC
+#endif
+#if !defined(STDC) && (defined(MSDOS) || defined(WINDOWS) || defined(WIN32))
+#  define STDC
+#endif
+#if !defined(STDC) && (defined(OS2) || defined(__HOS_AIX__))
+#  define STDC
+#endif
+
+#if defined(__OS400__) && !defined(STDC)    /* iSeries (formerly AS/400). */
+#  define STDC
+#endif
+
+#ifndef STDC
+#  ifndef const /* cannot use !defined(STDC) && !defined(const) on Mac */
+#    define const       /* note: need a more gentle solution here */
+#  endif
+#endif
+
+/* Some Mac compilers merge all .h files incorrectly: */
+#if defined(__MWERKS__)||defined(applec)||defined(THINK_C)||defined(__SC__)
+#  define NO_DUMMY_DECL
+#endif
+
+/* Maximum value for memLevel in deflateInit2 */
+#ifndef MAX_MEM_LEVEL
+#  ifdef MAXSEG_64K
+#    define MAX_MEM_LEVEL 8
+#  else
+#    define MAX_MEM_LEVEL 9
+#  endif
+#endif
+
+/* Maximum value for windowBits in deflateInit2 and inflateInit2.
+ * WARNING: reducing MAX_WBITS makes minigzip unable to extract .gz files
+ * created by gzip. (Files created by minigzip can still be extracted by
+ * gzip.)
+ */
+#ifndef MAX_WBITS
+#  define MAX_WBITS   15 /* 32K LZ77 window */
+#endif
+
+/* The memory requirements for deflate are (in bytes):
+            (1 << (windowBits+2)) +  (1 << (memLevel+9))
+ that is: 128K for windowBits=15  +  128K for memLevel = 8  (default values)
+ plus a few kilobytes for small objects. For example, if you want to reduce
+ the default memory requirements from 256K to 128K, compile with
+     make CFLAGS="-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7"
+ Of course this will generally degrade compression (there's no free lunch).
+
+   The memory requirements for inflate are (in bytes) 1 << windowBits
+ that is, 32K for windowBits=15 (default value) plus a few kilobytes
+ for small objects.
+*/
+
+                        /* Type declarations */
+
+#ifndef OF /* function prototypes */
+#  ifdef STDC
+#    define OF(args)  args
+#  else
+#    define OF(args)  ()
+#  endif
+#endif
+
+/* The following definitions for FAR are needed only for MSDOS mixed
+ * model programming (small or medium model with some far allocations).
+ * This was tested only with MSC; for other MSDOS compilers you may have
+ * to define NO_MEMCPY in zutil.h.  If you don't need the mixed model,
+ * just define FAR to be empty.
+ */
+#ifdef SYS16BIT
+#  if defined(M_I86SM) || defined(M_I86MM)
+     /* MSC small or medium model */
+#    define SMALL_MEDIUM
+#    ifdef _MSC_VER
+#      define FAR _far
+#    else
+#      define FAR far
+#    endif
+#  endif
+#  if (defined(__SMALL__) || defined(__MEDIUM__))
+     /* Turbo C small or medium model */
+#    define SMALL_MEDIUM
+#    ifdef __BORLANDC__
+#      define FAR _far
+#    else
+#      define FAR far
+#    endif
+#  endif
+#endif
+
+#if defined(WINDOWS) || defined(WIN32)
+   /* If building or using zlib as a DLL, define ZLIB_DLL.
+    * This is not mandatory, but it offers a little performance increase.
+    */
+#  ifdef ZLIB_DLL
+#    if defined(WIN32) && (!defined(__BORLANDC__) || (__BORLANDC__ >= 0x500))
+#      ifdef ZLIB_INTERNAL
+#        define ZEXTERN extern __declspec(dllexport)
+#      else
+#        define ZEXTERN extern __declspec(dllimport)
+#      endif
+#    endif
+#  endif  /* ZLIB_DLL */
+   /* If building or using zlib with the WINAPI/WINAPIV calling convention,
+    * define ZLIB_WINAPI.
+    * Caution: the standard ZLIB1.DLL is NOT compiled using ZLIB_WINAPI.
+    */
+#  ifdef ZLIB_WINAPI
+#    ifdef FAR
+#      undef FAR
+#    endif
+#    include <windows.h>
+     /* No need for _export, use ZLIB.DEF instead. */
+     /* For complete Windows compatibility, use WINAPI, not __stdcall. */
+#    define ZEXPORT WINAPI
+#    ifdef WIN32
+#      define ZEXPORTVA WINAPIV
+#    else
+#      define ZEXPORTVA FAR CDECL
+#    endif
+#  endif
+#endif
+
+#if defined (__BEOS__)
+#  ifdef ZLIB_DLL
+#    ifdef ZLIB_INTERNAL
+#      define ZEXPORT   __declspec(dllexport)
+#      define ZEXPORTVA __declspec(dllexport)
+#    else
+#      define ZEXPORT   __declspec(dllimport)
+#      define ZEXPORTVA __declspec(dllimport)
+#    endif
+#  endif
+#endif
+
+#ifndef ZEXTERN
+#  define ZEXTERN extern
+#endif
+#ifndef ZEXPORT
+#  define ZEXPORT
+#endif
+#ifndef ZEXPORTVA
+#  define ZEXPORTVA
+#endif
+
+#ifndef FAR
+#  define FAR
+#endif
+
+#if !defined(__MACTYPES__)
+typedef unsigned char  Byte;  /* 8 bits */
+#endif
+typedef unsigned int   uInt;  /* 16 bits or more */
+typedef unsigned long  uLong; /* 32 bits or more */
+
+#ifdef SMALL_MEDIUM
+   /* Borland C/C++ and some old MSC versions ignore FAR inside typedef */
+#  define Bytef Byte FAR
+#else
+   typedef Byte  FAR Bytef;
+#endif
+typedef char  FAR charf;
+typedef int   FAR intf;
+typedef uInt  FAR uIntf;
+typedef uLong FAR uLongf;
+
+#ifdef STDC
+   typedef void const *voidpc;
+   typedef void FAR   *voidpf;
+   typedef void       *voidp;
+#else
+   typedef Byte const *voidpc;
+   typedef Byte FAR   *voidpf;
+   typedef Byte       *voidp;
+#endif
+
+#if 0           /* HAVE_UNISTD_H -- this line is updated by ./configure */
+#  include <sys/types.h> /* for off_t */
+#  include <unistd.h>    /* for SEEK_* and off_t */
+#  ifdef VMS
+#    include <unixio.h>   /* for off_t */
+#  endif
+#  define z_off_t off_t
+#endif
+#ifndef SEEK_SET
+#  define SEEK_SET        0       /* Seek from beginning of file.  */
+#  define SEEK_CUR        1       /* Seek from current position.  */
+#  define SEEK_END        2       /* Set file pointer to EOF plus "offset" */
+#endif
+#ifndef z_off_t
+#  define z_off_t long
+#endif
+
+#if defined(__OS400__)
+#  define NO_vsnprintf
+#endif
+
+#if defined(__MVS__)
+#  define NO_vsnprintf
+#  ifdef FAR
+#    undef FAR
+#  endif
+#endif
+
+/* MVS linker does not support external names larger than 8 bytes */
+#if defined(__MVS__)
+#   pragma map(deflateInit_,"DEIN")
+#   pragma map(deflateInit2_,"DEIN2")
+#   pragma map(deflateEnd,"DEEND")
+#   pragma map(deflateBound,"DEBND")
+#   pragma map(inflateInit_,"ININ")
+#   pragma map(inflateInit2_,"ININ2")
+#   pragma map(inflateEnd,"INEND")
+#   pragma map(inflateSync,"INSY")
+#   pragma map(inflateSetDictionary,"INSEDI")
+#   pragma map(compressBound,"CMBND")
+#   pragma map(inflate_table,"INTABL")
+#   pragma map(inflate_fast,"INFA")
+#   pragma map(inflate_copyright,"INCOPY")
+#endif
+
+#endif /* ZCONF_H */
diff --git a/gs/zlib/zlib.3 b/gs/zlib/zlib.3
new file mode 100644
index 000000000..90b816287
--- /dev/null
+++ b/gs/zlib/zlib.3
@@ -0,0 +1,159 @@
+.TH ZLIB 3 "18 July 2005"
+.SH NAME
+zlib \- compression/decompression library
+.SH SYNOPSIS
+[see
+.I zlib.h
+for full description]
+.SH DESCRIPTION
+The
+.I zlib
+library is a general purpose data compression library.
+The code is thread safe.
+It provides in-memory compression and decompression functions,
+including integrity checks of the uncompressed data.
+This version of the library supports only one compression method (deflation)
+but other algorithms will be added later
+and will have the same stream interface.
+.LP
+Compression can be done in a single step if the buffers are large enough
+(for example if an input file is mmap'ed),
+or can be done by repeated calls of the compression function.
+In the latter case,
+the application must provide more input and/or consume the output
+(providing more output space) before each call.
+.LP
+The library also supports reading and writing files in
+.IR gzip (1)
+(.gz) format
+with an interface similar to that of stdio.
+.LP
+The library does not install any signal handler.
+The decoder checks the consistency of the compressed data,
+so the library should never crash even in case of corrupted input.
+.LP
+All functions of the compression library are documented in the file
+.IR zlib.h .
+The distribution source includes examples of use of the library
+in the files
+.I example.c
+and
+.IR minigzip.c .
+.LP
+Changes to this version are documented in the file
+.I ChangeLog
+that accompanies the source,
+and are concerned primarily with bug fixes and portability enhancements.
+.LP
+A Java implementation of
+.I zlib
+is available in the Java Development Kit 1.1:
+.IP
+http://www.javasoft.com/products/JDK/1.1/docs/api/Package-java.util.zip.html
+.LP
+A Perl interface to
+.IR zlib ,
+written by Paul Marquess (pmqs@cpan.org),
+is available at CPAN (Comprehensive Perl Archive Network) sites,
+including:
+.IP
+http://www.cpan.org/modules/by-module/Compress/
+.LP
+A Python interface to
+.IR zlib ,
+written by A.M. Kuchling (amk@magnet.com),
+is available in Python 1.5 and later versions:
+.IP
+http://www.python.org/doc/lib/module-zlib.html
+.LP
+A
+.I zlib
+binding for
+.IR tcl (1),
+written by Andreas Kupries (a.kupries@westend.com),
+is availlable at:
+.IP
+http://www.westend.com/~kupries/doc/trf/man/man.html
+.LP
+An experimental package to read and write files in .zip format,
+written on top of
+.I zlib
+by Gilles Vollant (info@winimage.com),
+is available at:
+.IP
+http://www.winimage.com/zLibDll/unzip.html
+and also in the
+.I contrib/minizip
+directory of the main
+.I zlib
+web site.
+.SH "SEE ALSO"
+The
+.I zlib
+web site can be found at either of these locations:
+.IP
+http://www.zlib.org
+.br
+http://www.gzip.org/zlib/
+.LP
+The data format used by the zlib library is described by RFC
+(Request for Comments) 1950 to 1952 in the files:
+.IP
+http://www.ietf.org/rfc/rfc1950.txt (concerning zlib format)
+.br
+http://www.ietf.org/rfc/rfc1951.txt (concerning deflate format)
+.br
+http://www.ietf.org/rfc/rfc1952.txt (concerning gzip format)
+.LP
+These documents are also available in other formats from:
+.IP
+ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html
+.LP
+Mark Nelson (markn@ieee.org) wrote an article about
+.I zlib
+for the Jan. 1997 issue of  Dr. Dobb's Journal;
+a copy of the article is available at:
+.IP
+http://dogma.net/markn/articles/zlibtool/zlibtool.htm
+.SH "REPORTING PROBLEMS"
+Before reporting a problem,
+please check the
+.I zlib
+web site to verify that you have the latest version of
+.IR zlib ;
+otherwise,
+obtain the latest version and see if the problem still exists.
+Please read the
+.I zlib
+FAQ at:
+.IP
+http://www.gzip.org/zlib/zlib_faq.html
+.LP
+before asking for help.
+Send questions and/or comments to zlib@gzip.org,
+or (for the Windows DLL version) to Gilles Vollant (info@winimage.com).
+.SH AUTHORS
+Version 1.2.3
+Copyright (C) 1995-2005 Jean-loup Gailly (jloup@gzip.org)
+and Mark Adler (madler@alumni.caltech.edu).
+.LP
+This software is provided "as-is,"
+without any express or implied warranty.
+In no event will the authors be held liable for any damages
+arising from the use of this software.
+See the distribution directory with respect to requirements
+governing redistribution.
+The deflate format used by
+.I zlib
+was defined by Phil Katz.
+The deflate and
+.I zlib
+specifications were written by L. Peter Deutsch.
+Thanks to all the people who reported problems and suggested various
+improvements in
+.IR zlib ;
+who are too numerous to cite here.
+.LP
+UNIX manual page by R. P. C. Rodgers,
+U.S. National Library of Medicine (rodgers@nlm.nih.gov).
+.\" end of man page
diff --git a/gs/zlib/zlib.h b/gs/zlib/zlib.h
new file mode 100644
index 000000000..022817927
--- /dev/null
+++ b/gs/zlib/zlib.h
@@ -0,0 +1,1357 @@
+/* zlib.h -- interface of the 'zlib' general purpose compression library
+  version 1.2.3, July 18th, 2005
+
+  Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+
+  Jean-loup Gailly        Mark Adler
+  jloup@gzip.org          madler@alumni.caltech.edu
+
+
+  The data format used by the zlib library is described by RFCs (Request for
+  Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
+  (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
+*/
+
+#ifndef ZLIB_H
+#define ZLIB_H
+
+#include "zconf.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define ZLIB_VERSION "1.2.3"
+#define ZLIB_VERNUM 0x1230
+
+/*
+     The 'zlib' compression library provides in-memory compression and
+  decompression functions, including integrity checks of the uncompressed
+  data.  This version of the library supports only one compression method
+  (deflation) but other algorithms will be added later and will have the same
+  stream interface.
+
+     Compression can be done in a single step if the buffers are large
+  enough (for example if an input file is mmap'ed), or can be done by
+  repeated calls of the compression function.  In the latter case, the
+  application must provide more input and/or consume the output
+  (providing more output space) before each call.
+
+     The compressed data format used by default by the in-memory functions is
+  the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
+  around a deflate stream, which is itself documented in RFC 1951.
+
+     The library also supports reading and writing files in gzip (.gz) format
+  with an interface similar to that of stdio using the functions that start
+  with "gz".  The gzip format is different from the zlib format.  gzip is a
+  gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
+
+     This library can optionally read and write gzip streams in memory as well.
+
+     The zlib format was designed to be compact and fast for use in memory
+  and on communications channels.  The gzip format was designed for single-
+  file compression on file systems, has a larger header than zlib to maintain
+  directory information, and uses a different, slower check method than zlib.
+
+     The library does not install any signal handler. The decoder checks
+  the consistency of the compressed data, so the library should never
+  crash even in case of corrupted input.
+*/
+
+typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
+typedef void   (*free_func)  OF((voidpf opaque, voidpf address));
+
+struct internal_state;
+
+typedef struct z_stream_s {
+    Bytef    *next_in;  /* next input byte */
+    uInt     avail_in;  /* number of bytes available at next_in */
+    uLong    total_in;  /* total nb of input bytes read so far */
+
+    Bytef    *next_out; /* next output byte should be put there */
+    uInt     avail_out; /* remaining free space at next_out */
+    uLong    total_out; /* total nb of bytes output so far */
+
+    char     *msg;      /* last error message, NULL if no error */
+    struct internal_state FAR *state; /* not visible by applications */
+
+    alloc_func zalloc;  /* used to allocate the internal state */
+    free_func  zfree;   /* used to free the internal state */
+    voidpf     opaque;  /* private data object passed to zalloc and zfree */
+
+    int     data_type;  /* best guess about the data type: binary or text */
+    uLong   adler;      /* adler32 value of the uncompressed data */
+    uLong   reserved;   /* reserved for future use */
+} z_stream;
+
+typedef z_stream FAR *z_streamp;
+
+/*
+     gzip header information passed to and from zlib routines.  See RFC 1952
+  for more details on the meanings of these fields.
+*/
+typedef struct gz_header_s {
+    int     text;       /* true if compressed data believed to be text */
+    uLong   time;       /* modification time */
+    int     xflags;     /* extra flags (not used when writing a gzip file) */
+    int     os;         /* operating system */
+    Bytef   *extra;     /* pointer to extra field or Z_NULL if none */
+    uInt    extra_len;  /* extra field length (valid if extra != Z_NULL) */
+    uInt    extra_max;  /* space at extra (only when reading header) */
+    Bytef   *name;      /* pointer to zero-terminated file name or Z_NULL */
+    uInt    name_max;   /* space at name (only when reading header) */
+    Bytef   *comment;   /* pointer to zero-terminated comment or Z_NULL */
+    uInt    comm_max;   /* space at comment (only when reading header) */
+    int     hcrc;       /* true if there was or will be a header crc */
+    int     done;       /* true when done reading gzip header (not used
+                           when writing a gzip file) */
+} gz_header;
+
+typedef gz_header FAR *gz_headerp;
+
+/*
+   The application must update next_in and avail_in when avail_in has
+   dropped to zero. It must update next_out and avail_out when avail_out
+   has dropped to zero. The application must initialize zalloc, zfree and
+   opaque before calling the init function. All other fields are set by the
+   compression library and must not be updated by the application.
+
+   The opaque value provided by the application will be passed as the first
+   parameter for calls of zalloc and zfree. This can be useful for custom
+   memory management. The compression library attaches no meaning to the
+   opaque value.
+
+   zalloc must return Z_NULL if there is not enough memory for the object.
+   If zlib is used in a multi-threaded application, zalloc and zfree must be
+   thread safe.
+
+   On 16-bit systems, the functions zalloc and zfree must be able to allocate
+   exactly 65536 bytes, but will not be required to allocate more than this
+   if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
+   pointers returned by zalloc for objects of exactly 65536 bytes *must*
+   have their offset normalized to zero. The default allocation function
+   provided by this library ensures this (see zutil.c). To reduce memory
+   requirements and avoid any allocation of 64K objects, at the expense of
+   compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
+
+   The fields total_in and total_out can be used for statistics or
+   progress reports. After compression, total_in holds the total size of
+   the uncompressed data and may be saved for use in the decompressor
+   (particularly if the decompressor wants to decompress everything in
+   a single step).
+*/
+
+                        /* constants */
+
+#define Z_NO_FLUSH      0
+#define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */
+#define Z_SYNC_FLUSH    2
+#define Z_FULL_FLUSH    3
+#define Z_FINISH        4
+#define Z_BLOCK         5
+/* Allowed flush values; see deflate() and inflate() below for details */
+
+#define Z_OK            0
+#define Z_STREAM_END    1
+#define Z_NEED_DICT     2
+#define Z_ERRNO        (-1)
+#define Z_STREAM_ERROR (-2)
+#define Z_DATA_ERROR   (-3)
+#define Z_MEM_ERROR    (-4)
+#define Z_BUF_ERROR    (-5)
+#define Z_VERSION_ERROR (-6)
+/* Return codes for the compression/decompression functions. Negative
+ * values are errors, positive values are used for special but normal events.
+ */
+
+#define Z_NO_COMPRESSION         0
+#define Z_BEST_SPEED             1
+#define Z_BEST_COMPRESSION       9
+#define Z_DEFAULT_COMPRESSION  (-1)
+/* compression levels */
+
+#define Z_FILTERED            1
+#define Z_HUFFMAN_ONLY        2
+#define Z_RLE                 3
+#define Z_FIXED               4
+#define Z_DEFAULT_STRATEGY    0
+/* compression strategy; see deflateInit2() below for details */
+
+#define Z_BINARY   0
+#define Z_TEXT     1
+#define Z_ASCII    Z_TEXT   /* for compatibility with 1.2.2 and earlier */
+#define Z_UNKNOWN  2
+/* Possible values of the data_type field (though see inflate()) */
+
+#define Z_DEFLATED   8
+/* The deflate compression method (the only one supported in this version) */
+
+#define Z_NULL  0  /* for initializing zalloc, zfree, opaque */
+
+#define zlib_version zlibVersion()
+/* for compatibility with versions < 1.0.2 */
+
+                        /* basic functions */
+
+ZEXTERN const char * ZEXPORT zlibVersion OF((void));
+/* The application can compare zlibVersion and ZLIB_VERSION for consistency.
+   If the first character differs, the library code actually used is
+   not compatible with the zlib.h header file used by the application.
+   This check is automatically made by deflateInit and inflateInit.
+ */
+
+/*
+ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
+
+     Initializes the internal stream state for compression. The fields
+   zalloc, zfree and opaque must be initialized before by the caller.
+   If zalloc and zfree are set to Z_NULL, deflateInit updates them to
+   use default allocation functions.
+
+     The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
+   1 gives best speed, 9 gives best compression, 0 gives no compression at
+   all (the input data is simply copied a block at a time).
+   Z_DEFAULT_COMPRESSION requests a default compromise between speed and
+   compression (currently equivalent to level 6).
+
+     deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
+   enough memory, Z_STREAM_ERROR if level is not a valid compression level,
+   Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
+   with the version assumed by the caller (ZLIB_VERSION).
+   msg is set to null if there is no error message.  deflateInit does not
+   perform any compression: this will be done by deflate().
+*/
+
+
+ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
+/*
+    deflate compresses as much data as possible, and stops when the input
+  buffer becomes empty or the output buffer becomes full. It may introduce some
+  output latency (reading input without producing any output) except when
+  forced to flush.
+
+    The detailed semantics are as follows. deflate performs one or both of the
+  following actions:
+
+  - Compress more input starting at next_in and update next_in and avail_in
+    accordingly. If not all input can be processed (because there is not
+    enough room in the output buffer), next_in and avail_in are updated and
+    processing will resume at this point for the next call of deflate().
+
+  - Provide more output starting at next_out and update next_out and avail_out
+    accordingly. This action is forced if the parameter flush is non zero.
+    Forcing flush frequently degrades the compression ratio, so this parameter
+    should be set only when necessary (in interactive applications).
+    Some output may be provided even if flush is not set.
+
+  Before the call of deflate(), the application should ensure that at least
+  one of the actions is possible, by providing more input and/or consuming
+  more output, and updating avail_in or avail_out accordingly; avail_out
+  should never be zero before the call. The application can consume the
+  compressed output when it wants, for example when the output buffer is full
+  (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
+  and with zero avail_out, it must be called again after making room in the
+  output buffer because there might be more output pending.
+
+    Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
+  decide how much data to accumualte before producing output, in order to
+  maximize compression.
+
+    If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
+  flushed to the output buffer and the output is aligned on a byte boundary, so
+  that the decompressor can get all input data available so far. (In particular
+  avail_in is zero after the call if enough output space has been provided
+  before the call.)  Flushing may degrade compression for some compression
+  algorithms and so it should be used only when necessary.
+
+    If flush is set to Z_FULL_FLUSH, all output is flushed as with
+  Z_SYNC_FLUSH, and the compression state is reset so that decompression can
+  restart from this point if previous compressed data has been damaged or if
+  random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
+  compression.
+
+    If deflate returns with avail_out == 0, this function must be called again
+  with the same value of the flush parameter and more output space (updated
+  avail_out), until the flush is complete (deflate returns with non-zero
+  avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
+  avail_out is greater than six to avoid repeated flush markers due to
+  avail_out == 0 on return.
+
+    If the parameter flush is set to Z_FINISH, pending input is processed,
+  pending output is flushed and deflate returns with Z_STREAM_END if there
+  was enough output space; if deflate returns with Z_OK, this function must be
+  called again with Z_FINISH and more output space (updated avail_out) but no
+  more input data, until it returns with Z_STREAM_END or an error. After
+  deflate has returned Z_STREAM_END, the only possible operations on the
+  stream are deflateReset or deflateEnd.
+
+    Z_FINISH can be used immediately after deflateInit if all the compression
+  is to be done in a single step. In this case, avail_out must be at least
+  the value returned by deflateBound (see below). If deflate does not return
+  Z_STREAM_END, then it must be called again as described above.
+
+    deflate() sets strm->adler to the adler32 checksum of all input read
+  so far (that is, total_in bytes).
+
+    deflate() may update strm->data_type if it can make a good guess about
+  the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered
+  binary. This field is only for information purposes and does not affect
+  the compression algorithm in any manner.
+
+    deflate() returns Z_OK if some progress has been made (more input
+  processed or more output produced), Z_STREAM_END if all input has been
+  consumed and all output has been produced (only when flush is set to
+  Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
+  if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible
+  (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
+  fatal, and deflate() can be called again with more input and more output
+  space to continue compressing.
+*/
+
+
+ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
+/*
+     All dynamically allocated data structures for this stream are freed.
+   This function discards any unprocessed input and does not flush any
+   pending output.
+
+     deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
+   stream state was inconsistent, Z_DATA_ERROR if the stream was freed
+   prematurely (some input or output was discarded). In the error case,
+   msg may be set but then points to a static string (which must not be
+   deallocated).
+*/
+
+
+/*
+ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
+
+     Initializes the internal stream state for decompression. The fields
+   next_in, avail_in, zalloc, zfree and opaque must be initialized before by
+   the caller. If next_in is not Z_NULL and avail_in is large enough (the exact
+   value depends on the compression method), inflateInit determines the
+   compression method from the zlib header and allocates all data structures
+   accordingly; otherwise the allocation will be deferred to the first call of
+   inflate.  If zalloc and zfree are set to Z_NULL, inflateInit updates them to
+   use default allocation functions.
+
+     inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
+   memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
+   version assumed by the caller.  msg is set to null if there is no error
+   message. inflateInit does not perform any decompression apart from reading
+   the zlib header if present: this will be done by inflate().  (So next_in and
+   avail_in may be modified, but next_out and avail_out are unchanged.)
+*/
+
+
+ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
+/*
+    inflate decompresses as much data as possible, and stops when the input
+  buffer becomes empty or the output buffer becomes full. It may introduce
+  some output latency (reading input without producing any output) except when
+  forced to flush.
+
+  The detailed semantics are as follows. inflate performs one or both of the
+  following actions:
+
+  - Decompress more input starting at next_in and update next_in and avail_in
+    accordingly. If not all input can be processed (because there is not
+    enough room in the output buffer), next_in is updated and processing
+    will resume at this point for the next call of inflate().
+
+  - Provide more output starting at next_out and update next_out and avail_out
+    accordingly.  inflate() provides as much output as possible, until there
+    is no more input data or no more space in the output buffer (see below
+    about the flush parameter).
+
+  Before the call of inflate(), the application should ensure that at least
+  one of the actions is possible, by providing more input and/or consuming
+  more output, and updating the next_* and avail_* values accordingly.
+  The application can consume the uncompressed output when it wants, for
+  example when the output buffer is full (avail_out == 0), or after each
+  call of inflate(). If inflate returns Z_OK and with zero avail_out, it
+  must be called again after making room in the output buffer because there
+  might be more output pending.
+
+    The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
+  Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
+  output as possible to the output buffer. Z_BLOCK requests that inflate() stop
+  if and when it gets to the next deflate block boundary. When decoding the
+  zlib or gzip format, this will cause inflate() to return immediately after
+  the header and before the first block. When doing a raw inflate, inflate()
+  will go ahead and process the first block, and will return when it gets to
+  the end of that block, or when it runs out of data.
+
+    The Z_BLOCK option assists in appending to or combining deflate streams.
+  Also to assist in this, on return inflate() will set strm->data_type to the
+  number of unused bits in the last byte taken from strm->next_in, plus 64
+  if inflate() is currently decoding the last block in the deflate stream,
+  plus 128 if inflate() returned immediately after decoding an end-of-block
+  code or decoding the complete header up to just before the first byte of the
+  deflate stream. The end-of-block will not be indicated until all of the
+  uncompressed data from that block has been written to strm->next_out.  The
+  number of unused bits may in general be greater than seven, except when
+  bit 7 of data_type is set, in which case the number of unused bits will be
+  less than eight.
+
+    inflate() should normally be called until it returns Z_STREAM_END or an
+  error. However if all decompression is to be performed in a single step
+  (a single call of inflate), the parameter flush should be set to
+  Z_FINISH. In this case all pending input is processed and all pending
+  output is flushed; avail_out must be large enough to hold all the
+  uncompressed data. (The size of the uncompressed data may have been saved
+  by the compressor for this purpose.) The next operation on this stream must
+  be inflateEnd to deallocate the decompression state. The use of Z_FINISH
+  is never required, but can be used to inform inflate that a faster approach
+  may be used for the single inflate() call.
+
+     In this implementation, inflate() always flushes as much output as
+  possible to the output buffer, and always uses the faster approach on the
+  first call. So the only effect of the flush parameter in this implementation
+  is on the return value of inflate(), as noted below, or when it returns early
+  because Z_BLOCK is used.
+
+     If a preset dictionary is needed after this call (see inflateSetDictionary
+  below), inflate sets strm->adler to the adler32 checksum of the dictionary
+  chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
+  strm->adler to the adler32 checksum of all output produced so far (that is,
+  total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
+  below. At the end of the stream, inflate() checks that its computed adler32
+  checksum is equal to that saved by the compressor and returns Z_STREAM_END
+  only if the checksum is correct.
+
+    inflate() will decompress and check either zlib-wrapped or gzip-wrapped
+  deflate data.  The header type is detected automatically.  Any information
+  contained in the gzip header is not retained, so applications that need that
+  information should instead use raw inflate, see inflateInit2() below, or
+  inflateBack() and perform their own processing of the gzip header and
+  trailer.
+
+    inflate() returns Z_OK if some progress has been made (more input processed
+  or more output produced), Z_STREAM_END if the end of the compressed data has
+  been reached and all uncompressed output has been produced, Z_NEED_DICT if a
+  preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
+  corrupted (input stream not conforming to the zlib format or incorrect check
+  value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
+  if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
+  Z_BUF_ERROR if no progress is possible or if there was not enough room in the
+  output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
+  inflate() can be called again with more input and more output space to
+  continue decompressing. If Z_DATA_ERROR is returned, the application may then
+  call inflateSync() to look for a good compression block if a partial recovery
+  of the data is desired.
+*/
+
+
+ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
+/*
+     All dynamically allocated data structures for this stream are freed.
+   This function discards any unprocessed input and does not flush any
+   pending output.
+
+     inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
+   was inconsistent. In the error case, msg may be set but then points to a
+   static string (which must not be deallocated).
+*/
+
+                        /* Advanced functions */
+
+/*
+    The following functions are needed only in some special applications.
+*/
+
+/*
+ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
+                                     int  level,
+                                     int  method,
+                                     int  windowBits,
+                                     int  memLevel,
+                                     int  strategy));
+
+     This is another version of deflateInit with more compression options. The
+   fields next_in, zalloc, zfree and opaque must be initialized before by
+   the caller.
+
+     The method parameter is the compression method. It must be Z_DEFLATED in
+   this version of the library.
+
+     The windowBits parameter is the base two logarithm of the window size
+   (the size of the history buffer). It should be in the range 8..15 for this
+   version of the library. Larger values of this parameter result in better
+   compression at the expense of memory usage. The default value is 15 if
+   deflateInit is used instead.
+
+     windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
+   determines the window size. deflate() will then generate raw deflate data
+   with no zlib header or trailer, and will not compute an adler32 check value.
+
+     windowBits can also be greater than 15 for optional gzip encoding. Add
+   16 to windowBits to write a simple gzip header and trailer around the
+   compressed data instead of a zlib wrapper. The gzip header will have no
+   file name, no extra data, no comment, no modification time (set to zero),
+   no header crc, and the operating system will be set to 255 (unknown).  If a
+   gzip stream is being written, strm->adler is a crc32 instead of an adler32.
+
+     The memLevel parameter specifies how much memory should be allocated
+   for the internal compression state. memLevel=1 uses minimum memory but
+   is slow and reduces compression ratio; memLevel=9 uses maximum memory
+   for optimal speed. The default value is 8. See zconf.h for total memory
+   usage as a function of windowBits and memLevel.
+
+     The strategy parameter is used to tune the compression algorithm. Use the
+   value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
+   filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
+   string match), or Z_RLE to limit match distances to one (run-length
+   encoding). Filtered data consists mostly of small values with a somewhat
+   random distribution. In this case, the compression algorithm is tuned to
+   compress them better. The effect of Z_FILTERED is to force more Huffman
+   coding and less string matching; it is somewhat intermediate between
+   Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as
+   Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy
+   parameter only affects the compression ratio but not the correctness of the
+   compressed output even if it is not set appropriately.  Z_FIXED prevents the
+   use of dynamic Huffman codes, allowing for a simpler decoder for special
+   applications.
+
+      deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
+   memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
+   method). msg is set to null if there is no error message.  deflateInit2 does
+   not perform any compression: this will be done by deflate().
+*/
+
+ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
+                                             const Bytef *dictionary,
+                                             uInt  dictLength));
+/*
+     Initializes the compression dictionary from the given byte sequence
+   without producing any compressed output. This function must be called
+   immediately after deflateInit, deflateInit2 or deflateReset, before any
+   call of deflate. The compressor and decompressor must use exactly the same
+   dictionary (see inflateSetDictionary).
+
+     The dictionary should consist of strings (byte sequences) that are likely
+   to be encountered later in the data to be compressed, with the most commonly
+   used strings preferably put towards the end of the dictionary. Using a
+   dictionary is most useful when the data to be compressed is short and can be
+   predicted with good accuracy; the data can then be compressed better than
+   with the default empty dictionary.
+
+     Depending on the size of the compression data structures selected by
+   deflateInit or deflateInit2, a part of the dictionary may in effect be
+   discarded, for example if the dictionary is larger than the window size in
+   deflate or deflate2. Thus the strings most likely to be useful should be
+   put at the end of the dictionary, not at the front. In addition, the
+   current implementation of deflate will use at most the window size minus
+   262 bytes of the provided dictionary.
+
+     Upon return of this function, strm->adler is set to the adler32 value
+   of the dictionary; the decompressor may later use this value to determine
+   which dictionary has been used by the compressor. (The adler32 value
+   applies to the whole dictionary even if only a subset of the dictionary is
+   actually used by the compressor.) If a raw deflate was requested, then the
+   adler32 value is not computed and strm->adler is not set.
+
+     deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
+   parameter is invalid (such as NULL dictionary) or the stream state is
+   inconsistent (for example if deflate has already been called for this stream
+   or if the compression method is bsort). deflateSetDictionary does not
+   perform any compression: this will be done by deflate().
+*/
+
+ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
+                                    z_streamp source));
+/*
+     Sets the destination stream as a complete copy of the source stream.
+
+     This function can be useful when several compression strategies will be
+   tried, for example when there are several ways of pre-processing the input
+   data with a filter. The streams that will be discarded should then be freed
+   by calling deflateEnd.  Note that deflateCopy duplicates the internal
+   compression state which can be quite large, so this strategy is slow and
+   can consume lots of memory.
+
+     deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
+   enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
+   (such as zalloc being NULL). msg is left unchanged in both source and
+   destination.
+*/
+
+ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
+/*
+     This function is equivalent to deflateEnd followed by deflateInit,
+   but does not free and reallocate all the internal compression state.
+   The stream will keep the same compression level and any other attributes
+   that may have been set by deflateInit2.
+
+      deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
+   stream state was inconsistent (such as zalloc or state being NULL).
+*/
+
+ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
+                                      int level,
+                                      int strategy));
+/*
+     Dynamically update the compression level and compression strategy.  The
+   interpretation of level and strategy is as in deflateInit2.  This can be
+   used to switch between compression and straight copy of the input data, or
+   to switch to a different kind of input data requiring a different
+   strategy. If the compression level is changed, the input available so far
+   is compressed with the old level (and may be flushed); the new level will
+   take effect only at the next call of deflate().
+
+     Before the call of deflateParams, the stream state must be set as for
+   a call of deflate(), since the currently available input may have to
+   be compressed and flushed. In particular, strm->avail_out must be non-zero.
+
+     deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
+   stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
+   if strm->avail_out was zero.
+*/
+
+ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
+                                    int good_length,
+                                    int max_lazy,
+                                    int nice_length,
+                                    int max_chain));
+/*
+     Fine tune deflate's internal compression parameters.  This should only be
+   used by someone who understands the algorithm used by zlib's deflate for
+   searching for the best matching string, and even then only by the most
+   fanatic optimizer trying to squeeze out the last compressed bit for their
+   specific input data.  Read the deflate.c source code for the meaning of the
+   max_lazy, good_length, nice_length, and max_chain parameters.
+
+     deflateTune() can be called after deflateInit() or deflateInit2(), and
+   returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
+ */
+
+ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
+                                       uLong sourceLen));
+/*
+     deflateBound() returns an upper bound on the compressed size after
+   deflation of sourceLen bytes.  It must be called after deflateInit()
+   or deflateInit2().  This would be used to allocate an output buffer
+   for deflation in a single pass, and so would be called before deflate().
+*/
+
+ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
+                                     int bits,
+                                     int value));
+/*
+     deflatePrime() inserts bits in the deflate output stream.  The intent
+  is that this function is used to start off the deflate output with the
+  bits leftover from a previous deflate stream when appending to it.  As such,
+  this function can only be used for raw deflate, and must be used before the
+  first deflate() call after a deflateInit2() or deflateReset().  bits must be
+  less than or equal to 16, and that many of the least significant bits of
+  value will be inserted in the output.
+
+      deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
+   stream state was inconsistent.
+*/
+
+ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
+                                         gz_headerp head));
+/*
+      deflateSetHeader() provides gzip header information for when a gzip
+   stream is requested by deflateInit2().  deflateSetHeader() may be called
+   after deflateInit2() or deflateReset() and before the first call of
+   deflate().  The text, time, os, extra field, name, and comment information
+   in the provided gz_header structure are written to the gzip header (xflag is
+   ignored -- the extra flags are set according to the compression level).  The
+   caller must assure that, if not Z_NULL, name and comment are terminated with
+   a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
+   available there.  If hcrc is true, a gzip header crc is included.  Note that
+   the current versions of the command-line version of gzip (up through version
+   1.3.x) do not support header crc's, and will report that it is a "multi-part
+   gzip file" and give up.
+
+      If deflateSetHeader is not used, the default gzip header has text false,
+   the time set to zero, and os set to 255, with no extra, name, or comment
+   fields.  The gzip header is returned to the default state by deflateReset().
+
+      deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
+   stream state was inconsistent.
+*/
+
+/*
+ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
+                                     int  windowBits));
+
+     This is another version of inflateInit with an extra parameter. The
+   fields next_in, avail_in, zalloc, zfree and opaque must be initialized
+   before by the caller.
+
+     The windowBits parameter is the base two logarithm of the maximum window
+   size (the size of the history buffer).  It should be in the range 8..15 for
+   this version of the library. The default value is 15 if inflateInit is used
+   instead. windowBits must be greater than or equal to the windowBits value
+   provided to deflateInit2() while compressing, or it must be equal to 15 if
+   deflateInit2() was not used. If a compressed stream with a larger window
+   size is given as input, inflate() will return with the error code
+   Z_DATA_ERROR instead of trying to allocate a larger window.
+
+     windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
+   determines the window size. inflate() will then process raw deflate data,
+   not looking for a zlib or gzip header, not generating a check value, and not
+   looking for any check values for comparison at the end of the stream. This
+   is for use with other formats that use the deflate compressed data format
+   such as zip.  Those formats provide their own check values. If a custom
+   format is developed using the raw deflate format for compressed data, it is
+   recommended that a check value such as an adler32 or a crc32 be applied to
+   the uncompressed data as is done in the zlib, gzip, and zip formats.  For
+   most applications, the zlib format should be used as is. Note that comments
+   above on the use in deflateInit2() applies to the magnitude of windowBits.
+
+     windowBits can also be greater than 15 for optional gzip decoding. Add
+   32 to windowBits to enable zlib and gzip decoding with automatic header
+   detection, or add 16 to decode only the gzip format (the zlib format will
+   return a Z_DATA_ERROR).  If a gzip stream is being decoded, strm->adler is
+   a crc32 instead of an adler32.
+
+     inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
+   memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg
+   is set to null if there is no error message.  inflateInit2 does not perform
+   any decompression apart from reading the zlib header if present: this will
+   be done by inflate(). (So next_in and avail_in may be modified, but next_out
+   and avail_out are unchanged.)
+*/
+
+ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
+                                             const Bytef *dictionary,
+                                             uInt  dictLength));
+/*
+     Initializes the decompression dictionary from the given uncompressed byte
+   sequence. This function must be called immediately after a call of inflate,
+   if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
+   can be determined from the adler32 value returned by that call of inflate.
+   The compressor and decompressor must use exactly the same dictionary (see
+   deflateSetDictionary).  For raw inflate, this function can be called
+   immediately after inflateInit2() or inflateReset() and before any call of
+   inflate() to set the dictionary.  The application must insure that the
+   dictionary that was used for compression is provided.
+
+     inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
+   parameter is invalid (such as NULL dictionary) or the stream state is
+   inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
+   expected one (incorrect adler32 value). inflateSetDictionary does not
+   perform any decompression: this will be done by subsequent calls of
+   inflate().
+*/
+
+ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
+/*
+    Skips invalid compressed data until a full flush point (see above the
+  description of deflate with Z_FULL_FLUSH) can be found, or until all
+  available input is skipped. No output is provided.
+
+    inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
+  if no more input was provided, Z_DATA_ERROR if no flush point has been found,
+  or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
+  case, the application may save the current current value of total_in which
+  indicates where valid compressed data was found. In the error case, the
+  application may repeatedly call inflateSync, providing more input each time,
+  until success or end of the input data.
+*/
+
+ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
+                                    z_streamp source));
+/*
+     Sets the destination stream as a complete copy of the source stream.
+
+     This function can be useful when randomly accessing a large stream.  The
+   first pass through the stream can periodically record the inflate state,
+   allowing restarting inflate at those points when randomly accessing the
+   stream.
+
+     inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
+   enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
+   (such as zalloc being NULL). msg is left unchanged in both source and
+   destination.
+*/
+
+ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
+/*
+     This function is equivalent to inflateEnd followed by inflateInit,
+   but does not free and reallocate all the internal decompression state.
+   The stream will keep attributes that may have been set by inflateInit2.
+
+      inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
+   stream state was inconsistent (such as zalloc or state being NULL).
+*/
+
+ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
+                                     int bits,
+                                     int value));
+/*
+     This function inserts bits in the inflate input stream.  The intent is
+  that this function is used to start inflating at a bit position in the
+  middle of a byte.  The provided bits will be used before any bytes are used
+  from next_in.  This function should only be used with raw inflate, and
+  should be used before the first inflate() call after inflateInit2() or
+  inflateReset().  bits must be less than or equal to 16, and that many of the
+  least significant bits of value will be inserted in the input.
+
+      inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
+   stream state was inconsistent.
+*/
+
+ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
+                                         gz_headerp head));
+/*
+      inflateGetHeader() requests that gzip header information be stored in the
+   provided gz_header structure.  inflateGetHeader() may be called after
+   inflateInit2() or inflateReset(), and before the first call of inflate().
+   As inflate() processes the gzip stream, head->done is zero until the header
+   is completed, at which time head->done is set to one.  If a zlib stream is
+   being decoded, then head->done is set to -1 to indicate that there will be
+   no gzip header information forthcoming.  Note that Z_BLOCK can be used to
+   force inflate() to return immediately after header processing is complete
+   and before any actual data is decompressed.
+
+      The text, time, xflags, and os fields are filled in with the gzip header
+   contents.  hcrc is set to true if there is a header CRC.  (The header CRC
+   was valid if done is set to one.)  If extra is not Z_NULL, then extra_max
+   contains the maximum number of bytes to write to extra.  Once done is true,
+   extra_len contains the actual extra field length, and extra contains the
+   extra field, or that field truncated if extra_max is less than extra_len.
+   If name is not Z_NULL, then up to name_max characters are written there,
+   terminated with a zero unless the length is greater than name_max.  If
+   comment is not Z_NULL, then up to comm_max characters are written there,
+   terminated with a zero unless the length is greater than comm_max.  When
+   any of extra, name, or comment are not Z_NULL and the respective field is
+   not present in the header, then that field is set to Z_NULL to signal its
+   absence.  This allows the use of deflateSetHeader() with the returned
+   structure to duplicate the header.  However if those fields are set to
+   allocated memory, then the application will need to save those pointers
+   elsewhere so that they can be eventually freed.
+
+      If inflateGetHeader is not used, then the header information is simply
+   discarded.  The header is always checked for validity, including the header
+   CRC if present.  inflateReset() will reset the process to discard the header
+   information.  The application would need to call inflateGetHeader() again to
+   retrieve the header from the next gzip stream.
+
+      inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
+   stream state was inconsistent.
+*/
+
+/*
+ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
+                                        unsigned char FAR *window));
+
+     Initialize the internal stream state for decompression using inflateBack()
+   calls.  The fields zalloc, zfree and opaque in strm must be initialized
+   before the call.  If zalloc and zfree are Z_NULL, then the default library-
+   derived memory allocation routines are used.  windowBits is the base two
+   logarithm of the window size, in the range 8..15.  window is a caller
+   supplied buffer of that size.  Except for special applications where it is
+   assured that deflate was used with small window sizes, windowBits must be 15
+   and a 32K byte window must be supplied to be able to decompress general
+   deflate streams.
+
+     See inflateBack() for the usage of these routines.
+
+     inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
+   the paramaters are invalid, Z_MEM_ERROR if the internal state could not
+   be allocated, or Z_VERSION_ERROR if the version of the library does not
+   match the version of the header file.
+*/
+
+typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
+typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
+
+ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
+                                    in_func in, void FAR *in_desc,
+                                    out_func out, void FAR *out_desc));
+/*
+     inflateBack() does a raw inflate with a single call using a call-back
+   interface for input and output.  This is more efficient than inflate() for
+   file i/o applications in that it avoids copying between the output and the
+   sliding window by simply making the window itself the output buffer.  This
+   function trusts the application to not change the output buffer passed by
+   the output function, at least until inflateBack() returns.
+
+     inflateBackInit() must be called first to allocate the internal state
+   and to initialize the state with the user-provided window buffer.
+   inflateBack() may then be used multiple times to inflate a complete, raw
+   deflate stream with each call.  inflateBackEnd() is then called to free
+   the allocated state.
+
+     A raw deflate stream is one with no zlib or gzip header or trailer.
+   This routine would normally be used in a utility that reads zip or gzip
+   files and writes out uncompressed files.  The utility would decode the
+   header and process the trailer on its own, hence this routine expects
+   only the raw deflate stream to decompress.  This is different from the
+   normal behavior of inflate(), which expects either a zlib or gzip header and
+   trailer around the deflate stream.
+
+     inflateBack() uses two subroutines supplied by the caller that are then
+   called by inflateBack() for input and output.  inflateBack() calls those
+   routines until it reads a complete deflate stream and writes out all of the
+   uncompressed data, or until it encounters an error.  The function's
+   parameters and return types are defined above in the in_func and out_func
+   typedefs.  inflateBack() will call in(in_desc, &buf) which should return the
+   number of bytes of provided input, and a pointer to that input in buf.  If
+   there is no input available, in() must return zero--buf is ignored in that
+   case--and inflateBack() will return a buffer error.  inflateBack() will call
+   out(out_desc, buf, len) to write the uncompressed data buf[0..len-1].  out()
+   should return zero on success, or non-zero on failure.  If out() returns
+   non-zero, inflateBack() will return with an error.  Neither in() nor out()
+   are permitted to change the contents of the window provided to
+   inflateBackInit(), which is also the buffer that out() uses to write from.
+   The length written by out() will be at most the window size.  Any non-zero
+   amount of input may be provided by in().
+
+     For convenience, inflateBack() can be provided input on the first call by
+   setting strm->next_in and strm->avail_in.  If that input is exhausted, then
+   in() will be called.  Therefore strm->next_in must be initialized before
+   calling inflateBack().  If strm->next_in is Z_NULL, then in() will be called
+   immediately for input.  If strm->next_in is not Z_NULL, then strm->avail_in
+   must also be initialized, and then if strm->avail_in is not zero, input will
+   initially be taken from strm->next_in[0 .. strm->avail_in - 1].
+
+     The in_desc and out_desc parameters of inflateBack() is passed as the
+   first parameter of in() and out() respectively when they are called.  These
+   descriptors can be optionally used to pass any information that the caller-
+   supplied in() and out() functions need to do their job.
+
+     On return, inflateBack() will set strm->next_in and strm->avail_in to
+   pass back any unused input that was provided by the last in() call.  The
+   return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
+   if in() or out() returned an error, Z_DATA_ERROR if there was a format
+   error in the deflate stream (in which case strm->msg is set to indicate the
+   nature of the error), or Z_STREAM_ERROR if the stream was not properly
+   initialized.  In the case of Z_BUF_ERROR, an input or output error can be
+   distinguished using strm->next_in which will be Z_NULL only if in() returned
+   an error.  If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to
+   out() returning non-zero.  (in() will always be called before out(), so
+   strm->next_in is assured to be defined if out() returns non-zero.)  Note
+   that inflateBack() cannot return Z_OK.
+*/
+
+ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
+/*
+     All memory allocated by inflateBackInit() is freed.
+
+     inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
+   state was inconsistent.
+*/
+
+ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
+/* Return flags indicating compile-time options.
+
+    Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
+     1.0: size of uInt
+     3.2: size of uLong
+     5.4: size of voidpf (pointer)
+     7.6: size of z_off_t
+
+    Compiler, assembler, and debug options:
+     8: DEBUG
+     9: ASMV or ASMINF -- use ASM code
+     10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
+     11: 0 (reserved)
+
+    One-time table building (smaller code, but not thread-safe if true):
+     12: BUILDFIXED -- build static block decoding tables when needed
+     13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
+     14,15: 0 (reserved)
+
+    Library content (indicates missing functionality):
+     16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
+                          deflate code when not needed)
+     17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
+                    and decode gzip streams (to avoid linking crc code)
+     18-19: 0 (reserved)
+
+    Operation variations (changes in library functionality):
+     20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
+     21: FASTEST -- deflate algorithm with only one, lowest compression level
+     22,23: 0 (reserved)
+
+    The sprintf variant used by gzprintf (zero is best):
+     24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
+     25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
+     26: 0 = returns value, 1 = void -- 1 means inferred string length returned
+
+    Remainder:
+     27-31: 0 (reserved)
+ */
+
+
+                        /* utility functions */
+
+/*
+     The following utility functions are implemented on top of the
+   basic stream-oriented functions. To simplify the interface, some
+   default options are assumed (compression level and memory usage,
+   standard memory allocation functions). The source code of these
+   utility functions can easily be modified if you need special options.
+*/
+
+ZEXTERN int ZEXPORT compress OF((Bytef *dest,   uLongf *destLen,
+                                 const Bytef *source, uLong sourceLen));
+/*
+     Compresses the source buffer into the destination buffer.  sourceLen is
+   the byte length of the source buffer. Upon entry, destLen is the total
+   size of the destination buffer, which must be at least the value returned
+   by compressBound(sourceLen). Upon exit, destLen is the actual size of the
+   compressed buffer.
+     This function can be used to compress a whole file at once if the
+   input file is mmap'ed.
+     compress returns Z_OK if success, Z_MEM_ERROR if there was not
+   enough memory, Z_BUF_ERROR if there was not enough room in the output
+   buffer.
+*/
+
+ZEXTERN int ZEXPORT compress2 OF((Bytef *dest,   uLongf *destLen,
+                                  const Bytef *source, uLong sourceLen,
+                                  int level));
+/*
+     Compresses the source buffer into the destination buffer. The level
+   parameter has the same meaning as in deflateInit.  sourceLen is the byte
+   length of the source buffer. Upon entry, destLen is the total size of the
+   destination buffer, which must be at least the value returned by
+   compressBound(sourceLen). Upon exit, destLen is the actual size of the
+   compressed buffer.
+
+     compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
+   memory, Z_BUF_ERROR if there was not enough room in the output buffer,
+   Z_STREAM_ERROR if the level parameter is invalid.
+*/
+
+ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
+/*
+     compressBound() returns an upper bound on the compressed size after
+   compress() or compress2() on sourceLen bytes.  It would be used before
+   a compress() or compress2() call to allocate the destination buffer.
+*/
+
+ZEXTERN int ZEXPORT uncompress OF((Bytef *dest,   uLongf *destLen,
+                                   const Bytef *source, uLong sourceLen));
+/*
+     Decompresses the source buffer into the destination buffer.  sourceLen is
+   the byte length of the source buffer. Upon entry, destLen is the total
+   size of the destination buffer, which must be large enough to hold the
+   entire uncompressed data. (The size of the uncompressed data must have
+   been saved previously by the compressor and transmitted to the decompressor
+   by some mechanism outside the scope of this compression library.)
+   Upon exit, destLen is the actual size of the compressed buffer.
+     This function can be used to decompress a whole file at once if the
+   input file is mmap'ed.
+
+     uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
+   enough memory, Z_BUF_ERROR if there was not enough room in the output
+   buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
+*/
+
+
+typedef voidp gzFile;
+
+ZEXTERN gzFile ZEXPORT gzopen  OF((const char *path, const char *mode));
+/*
+     Opens a gzip (.gz) file for reading or writing. The mode parameter
+   is as in fopen ("rb" or "wb") but can also include a compression level
+   ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for
+   Huffman only compression as in "wb1h", or 'R' for run-length encoding
+   as in "wb1R". (See the description of deflateInit2 for more information
+   about the strategy parameter.)
+
+     gzopen can be used to read a file which is not in gzip format; in this
+   case gzread will directly read from the file without decompression.
+
+     gzopen returns NULL if the file could not be opened or if there was
+   insufficient memory to allocate the (de)compression state; errno
+   can be checked to distinguish the two cases (if errno is zero, the
+   zlib error is Z_MEM_ERROR).  */
+
+ZEXTERN gzFile ZEXPORT gzdopen  OF((int fd, const char *mode));
+/*
+     gzdopen() associates a gzFile with the file descriptor fd.  File
+   descriptors are obtained from calls like open, dup, creat, pipe or
+   fileno (in the file has been previously opened with fopen).
+   The mode parameter is as in gzopen.
+     The next call of gzclose on the returned gzFile will also close the
+   file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
+   descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode).
+     gzdopen returns NULL if there was insufficient memory to allocate
+   the (de)compression state.
+*/
+
+ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
+/*
+     Dynamically update the compression level or strategy. See the description
+   of deflateInit2 for the meaning of these parameters.
+     gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
+   opened for writing.
+*/
+
+ZEXTERN int ZEXPORT    gzread  OF((gzFile file, voidp buf, unsigned len));
+/*
+     Reads the given number of uncompressed bytes from the compressed file.
+   If the input file was not in gzip format, gzread copies the given number
+   of bytes into the buffer.
+     gzread returns the number of uncompressed bytes actually read (0 for
+   end of file, -1 for error). */
+
+ZEXTERN int ZEXPORT    gzwrite OF((gzFile file,
+                                   voidpc buf, unsigned len));
+/*
+     Writes the given number of uncompressed bytes into the compressed file.
+   gzwrite returns the number of uncompressed bytes actually written
+   (0 in case of error).
+*/
+
+ZEXTERN int ZEXPORTVA   gzprintf OF((gzFile file, const char *format, ...));
+/*
+     Converts, formats, and writes the args to the compressed file under
+   control of the format string, as in fprintf. gzprintf returns the number of
+   uncompressed bytes actually written (0 in case of error).  The number of
+   uncompressed bytes written is limited to 4095. The caller should assure that
+   this limit is not exceeded. If it is exceeded, then gzprintf() will return
+   return an error (0) with nothing written. In this case, there may also be a
+   buffer overflow with unpredictable consequences, which is possible only if
+   zlib was compiled with the insecure functions sprintf() or vsprintf()
+   because the secure snprintf() or vsnprintf() functions were not available.
+*/
+
+ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
+/*
+      Writes the given null-terminated string to the compressed file, excluding
+   the terminating null character.
+      gzputs returns the number of characters written, or -1 in case of error.
+*/
+
+ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
+/*
+      Reads bytes from the compressed file until len-1 characters are read, or
+   a newline character is read and transferred to buf, or an end-of-file
+   condition is encountered.  The string is then terminated with a null
+   character.
+      gzgets returns buf, or Z_NULL in case of error.
+*/
+
+ZEXTERN int ZEXPORT    gzputc OF((gzFile file, int c));
+/*
+      Writes c, converted to an unsigned char, into the compressed file.
+   gzputc returns the value that was written, or -1 in case of error.
+*/
+
+ZEXTERN int ZEXPORT    gzgetc OF((gzFile file));
+/*
+      Reads one byte from the compressed file. gzgetc returns this byte
+   or -1 in case of end of file or error.
+*/
+
+ZEXTERN int ZEXPORT    gzungetc OF((int c, gzFile file));
+/*
+      Push one character back onto the stream to be read again later.
+   Only one character of push-back is allowed.  gzungetc() returns the
+   character pushed, or -1 on failure.  gzungetc() will fail if a
+   character has been pushed but not read yet, or if c is -1. The pushed
+   character will be discarded if the stream is repositioned with gzseek()
+   or gzrewind().
+*/
+
+ZEXTERN int ZEXPORT    gzflush OF((gzFile file, int flush));
+/*
+     Flushes all pending output into the compressed file. The parameter
+   flush is as in the deflate() function. The return value is the zlib
+   error number (see function gzerror below). gzflush returns Z_OK if
+   the flush parameter is Z_FINISH and all output could be flushed.
+     gzflush should be called only when strictly necessary because it can
+   degrade compression.
+*/
+
+ZEXTERN z_off_t ZEXPORT    gzseek OF((gzFile file,
+                                      z_off_t offset, int whence));
+/*
+      Sets the starting position for the next gzread or gzwrite on the
+   given compressed file. The offset represents a number of bytes in the
+   uncompressed data stream. The whence parameter is defined as in lseek(2);
+   the value SEEK_END is not supported.
+     If the file is opened for reading, this function is emulated but can be
+   extremely slow. If the file is opened for writing, only forward seeks are
+   supported; gzseek then compresses a sequence of zeroes up to the new
+   starting position.
+
+      gzseek returns the resulting offset location as measured in bytes from
+   the beginning of the uncompressed stream, or -1 in case of error, in
+   particular if the file is opened for writing and the new starting position
+   would be before the current position.
+*/
+
+ZEXTERN int ZEXPORT    gzrewind OF((gzFile file));
+/*
+     Rewinds the given file. This function is supported only for reading.
+
+   gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
+*/
+
+ZEXTERN z_off_t ZEXPORT    gztell OF((gzFile file));
+/*
+     Returns the starting position for the next gzread or gzwrite on the
+   given compressed file. This position represents a number of bytes in the
+   uncompressed data stream.
+
+   gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
+*/
+
+ZEXTERN int ZEXPORT gzeof OF((gzFile file));
+/*
+     Returns 1 when EOF has previously been detected reading the given
+   input stream, otherwise zero.
+*/
+
+ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
+/*
+     Returns 1 if file is being read directly without decompression, otherwise
+   zero.
+*/
+
+ZEXTERN int ZEXPORT    gzclose OF((gzFile file));
+/*
+     Flushes all pending output if necessary, closes the compressed file
+   and deallocates all the (de)compression state. The return value is the zlib
+   error number (see function gzerror below).
+*/
+
+ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
+/*
+     Returns the error message for the last error which occurred on the
+   given compressed file. errnum is set to zlib error number. If an
+   error occurred in the file system and not in the compression library,
+   errnum is set to Z_ERRNO and the application may consult errno
+   to get the exact error code.
+*/
+
+ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
+/*
+     Clears the error and end-of-file flags for file. This is analogous to the
+   clearerr() function in stdio. This is useful for continuing to read a gzip
+   file that is being written concurrently.
+*/
+
+                        /* checksum functions */
+
+/*
+     These functions are not related to compression but are exported
+   anyway because they might be useful in applications using the
+   compression library.
+*/
+
+ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
+/*
+     Update a running Adler-32 checksum with the bytes buf[0..len-1] and
+   return the updated checksum. If buf is NULL, this function returns
+   the required initial value for the checksum.
+   An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
+   much faster. Usage example:
+
+     uLong adler = adler32(0L, Z_NULL, 0);
+
+     while (read_buffer(buffer, length) != EOF) {
+       adler = adler32(adler, buffer, length);
+     }
+     if (adler != original_adler) error();
+*/
+
+ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
+                                          z_off_t len2));
+/*
+     Combine two Adler-32 checksums into one.  For two sequences of bytes, seq1
+   and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
+   each, adler1 and adler2.  adler32_combine() returns the Adler-32 checksum of
+   seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
+*/
+
+ZEXTERN uLong ZEXPORT crc32   OF((uLong crc, const Bytef *buf, uInt len));
+/*
+     Update a running CRC-32 with the bytes buf[0..len-1] and return the
+   updated CRC-32. If buf is NULL, this function returns the required initial
+   value for the for the crc. Pre- and post-conditioning (one's complement) is
+   performed within this function so it shouldn't be done by the application.
+   Usage example:
+
+     uLong crc = crc32(0L, Z_NULL, 0);
+
+     while (read_buffer(buffer, length) != EOF) {
+       crc = crc32(crc, buffer, length);
+     }
+     if (crc != original_crc) error();
+*/
+
+ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
+
+/*
+     Combine two CRC-32 check values into one.  For two sequences of bytes,
+   seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
+   calculated for each, crc1 and crc2.  crc32_combine() returns the CRC-32
+   check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
+   len2.
+*/
+
+
+                        /* various hacks, don't look :) */
+
+/* deflateInit and inflateInit are macros to allow checking the zlib version
+ * and the compiler's view of z_stream:
+ */
+ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
+                                     const char *version, int stream_size));
+ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
+                                     const char *version, int stream_size));
+ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int  level, int  method,
+                                      int windowBits, int memLevel,
+                                      int strategy, const char *version,
+                                      int stream_size));
+ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int  windowBits,
+                                      const char *version, int stream_size));
+ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
+                                         unsigned char FAR *window,
+                                         const char *version,
+                                         int stream_size));
+#define deflateInit(strm, level) \
+        deflateInit_((strm), (level),       ZLIB_VERSION, sizeof(z_stream))
+#define inflateInit(strm) \
+        inflateInit_((strm),                ZLIB_VERSION, sizeof(z_stream))
+#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
+        deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
+                      (strategy),           ZLIB_VERSION, sizeof(z_stream))
+#define inflateInit2(strm, windowBits) \
+        inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
+#define inflateBackInit(strm, windowBits, window) \
+        inflateBackInit_((strm), (windowBits), (window), \
+        ZLIB_VERSION, sizeof(z_stream))
+
+
+#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
+    struct internal_state {int dummy;}; /* hack for buggy compilers */
+#endif
+
+ZEXTERN const char   * ZEXPORT zError           OF((int));
+ZEXTERN int            ZEXPORT inflateSyncPoint OF((z_streamp z));
+ZEXTERN const uLongf * ZEXPORT get_crc_table    OF((void));
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ZLIB_H */
diff --git a/gs/zlib/zutil.c b/gs/zlib/zutil.c
new file mode 100644
index 000000000..d55f5948a
--- /dev/null
+++ b/gs/zlib/zutil.c
@@ -0,0 +1,318 @@
+/* zutil.c -- target dependent utility functions for the compression library
+ * Copyright (C) 1995-2005 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* @(#) $Id$ */
+
+#include "zutil.h"
+
+#ifndef NO_DUMMY_DECL
+struct internal_state      {int dummy;}; /* for buggy compilers */
+#endif
+
+const char * const z_errmsg[10] = {
+"need dictionary",     /* Z_NEED_DICT       2  */
+"stream end",          /* Z_STREAM_END      1  */
+"",                    /* Z_OK              0  */
+"file error",          /* Z_ERRNO         (-1) */
+"stream error",        /* Z_STREAM_ERROR  (-2) */
+"data error",          /* Z_DATA_ERROR    (-3) */
+"insufficient memory", /* Z_MEM_ERROR     (-4) */
+"buffer error",        /* Z_BUF_ERROR     (-5) */
+"incompatible version",/* Z_VERSION_ERROR (-6) */
+""};
+
+
+const char * ZEXPORT zlibVersion()
+{
+    return ZLIB_VERSION;
+}
+
+uLong ZEXPORT zlibCompileFlags()
+{
+    uLong flags;
+
+    flags = 0;
+    switch (sizeof(uInt)) {
+    case 2:     break;
+    case 4:     flags += 1;     break;
+    case 8:     flags += 2;     break;
+    default:    flags += 3;
+    }
+    switch (sizeof(uLong)) {
+    case 2:     break;
+    case 4:     flags += 1 << 2;        break;
+    case 8:     flags += 2 << 2;        break;
+    default:    flags += 3 << 2;
+    }
+    switch (sizeof(voidpf)) {
+    case 2:     break;
+    case 4:     flags += 1 << 4;        break;
+    case 8:     flags += 2 << 4;        break;
+    default:    flags += 3 << 4;
+    }
+    switch (sizeof(z_off_t)) {
+    case 2:     break;
+    case 4:     flags += 1 << 6;        break;
+    case 8:     flags += 2 << 6;        break;
+    default:    flags += 3 << 6;
+    }
+#ifdef DEBUG
+    flags += 1 << 8;
+#endif
+#if defined(ASMV) || defined(ASMINF)
+    flags += 1 << 9;
+#endif
+#ifdef ZLIB_WINAPI
+    flags += 1 << 10;
+#endif
+#ifdef BUILDFIXED
+    flags += 1 << 12;
+#endif
+#ifdef DYNAMIC_CRC_TABLE
+    flags += 1 << 13;
+#endif
+#ifdef NO_GZCOMPRESS
+    flags += 1L << 16;
+#endif
+#ifdef NO_GZIP
+    flags += 1L << 17;
+#endif
+#ifdef PKZIP_BUG_WORKAROUND
+    flags += 1L << 20;
+#endif
+#ifdef FASTEST
+    flags += 1L << 21;
+#endif
+#ifdef STDC
+#  ifdef NO_vsnprintf
+        flags += 1L << 25;
+#    ifdef HAS_vsprintf_void
+        flags += 1L << 26;
+#    endif
+#  else
+#    ifdef HAS_vsnprintf_void
+        flags += 1L << 26;
+#    endif
+#  endif
+#else
+        flags += 1L << 24;
+#  ifdef NO_snprintf
+        flags += 1L << 25;
+#    ifdef HAS_sprintf_void
+        flags += 1L << 26;
+#    endif
+#  else
+#    ifdef HAS_snprintf_void
+        flags += 1L << 26;
+#    endif
+#  endif
+#endif
+    return flags;
+}
+
+#ifdef DEBUG
+
+#  ifndef verbose
+#    define verbose 0
+#  endif
+int z_verbose = verbose;
+
+void z_error (m)
+    char *m;
+{
+    fprintf(stderr, "%s\n", m);
+    exit(1);
+}
+#endif
+
+/* exported to allow conversion of error code to string for compress() and
+ * uncompress()
+ */
+const char * ZEXPORT zError(err)
+    int err;
+{
+    return ERR_MSG(err);
+}
+
+#if defined(_WIN32_WCE)
+    /* The Microsoft C Run-Time Library for Windows CE doesn't have
+     * errno.  We define it as a global variable to simplify porting.
+     * Its value is always 0 and should not be used.
+     */
+    int errno = 0;
+#endif
+
+#ifndef HAVE_MEMCPY
+
+void zmemcpy(dest, source, len)
+    Bytef* dest;
+    const Bytef* source;
+    uInt  len;
+{
+    if (len == 0) return;
+    do {
+        *dest++ = *source++; /* ??? to be unrolled */
+    } while (--len != 0);
+}
+
+int zmemcmp(s1, s2, len)
+    const Bytef* s1;
+    const Bytef* s2;
+    uInt  len;
+{
+    uInt j;
+
+    for (j = 0; j < len; j++) {
+        if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
+    }
+    return 0;
+}
+
+void zmemzero(dest, len)
+    Bytef* dest;
+    uInt  len;
+{
+    if (len == 0) return;
+    do {
+        *dest++ = 0;  /* ??? to be unrolled */
+    } while (--len != 0);
+}
+#endif
+
+
+#ifdef SYS16BIT
+
+#ifdef __TURBOC__
+/* Turbo C in 16-bit mode */
+
+#  define MY_ZCALLOC
+
+/* Turbo C malloc() does not allow dynamic allocation of 64K bytes
+ * and farmalloc(64K) returns a pointer with an offset of 8, so we
+ * must fix the pointer. Warning: the pointer must be put back to its
+ * original form in order to free it, use zcfree().
+ */
+
+#define MAX_PTR 10
+/* 10*64K = 640K */
+
+local int next_ptr = 0;
+
+typedef struct ptr_table_s {
+    voidpf org_ptr;
+    voidpf new_ptr;
+} ptr_table;
+
+local ptr_table table[MAX_PTR];
+/* This table is used to remember the original form of pointers
+ * to large buffers (64K). Such pointers are normalized with a zero offset.
+ * Since MSDOS is not a preemptive multitasking OS, this table is not
+ * protected from concurrent access. This hack doesn't work anyway on
+ * a protected system like OS/2. Use Microsoft C instead.
+ */
+
+voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
+{
+    voidpf buf = opaque; /* just to make some compilers happy */
+    ulg bsize = (ulg)items*size;
+
+    /* If we allocate less than 65520 bytes, we assume that farmalloc
+     * will return a usable pointer which doesn't have to be normalized.
+     */
+    if (bsize < 65520L) {
+        buf = farmalloc(bsize);
+        if (*(ush*)&buf != 0) return buf;
+    } else {
+        buf = farmalloc(bsize + 16L);
+    }
+    if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
+    table[next_ptr].org_ptr = buf;
+
+    /* Normalize the pointer to seg:0 */
+    *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
+    *(ush*)&buf = 0;
+    table[next_ptr++].new_ptr = buf;
+    return buf;
+}
+
+void  zcfree (voidpf opaque, voidpf ptr)
+{
+    int n;
+    if (*(ush*)&ptr != 0) { /* object < 64K */
+        farfree(ptr);
+        return;
+    }
+    /* Find the original pointer */
+    for (n = 0; n < next_ptr; n++) {
+        if (ptr != table[n].new_ptr) continue;
+
+        farfree(table[n].org_ptr);
+        while (++n < next_ptr) {
+            table[n-1] = table[n];
+        }
+        next_ptr--;
+        return;
+    }
+    ptr = opaque; /* just to make some compilers happy */
+    Assert(0, "zcfree: ptr not found");
+}
+
+#endif /* __TURBOC__ */
+
+
+#ifdef M_I86
+/* Microsoft C in 16-bit mode */
+
+#  define MY_ZCALLOC
+
+#if (!defined(_MSC_VER) || (_MSC_VER <= 600))
+#  define _halloc  halloc
+#  define _hfree   hfree
+#endif
+
+voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
+{
+    if (opaque) opaque = 0; /* to make compiler happy */
+    return _halloc((long)items, size);
+}
+
+void  zcfree (voidpf opaque, voidpf ptr)
+{
+    if (opaque) opaque = 0; /* to make compiler happy */
+    _hfree(ptr);
+}
+
+#endif /* M_I86 */
+
+#endif /* SYS16BIT */
+
+
+#ifndef MY_ZCALLOC /* Any system without a special alloc function */
+
+#ifndef STDC
+extern voidp  malloc OF((uInt size));
+extern voidp  calloc OF((uInt items, uInt size));
+extern void   free   OF((voidpf ptr));
+#endif
+
+voidpf zcalloc (opaque, items, size)
+    voidpf opaque;
+    unsigned items;
+    unsigned size;
+{
+    if (opaque) items += size - size; /* make compiler happy */
+    return sizeof(uInt) > 2 ? (voidpf)malloc(items * size) :
+                              (voidpf)calloc(items, size);
+}
+
+void  zcfree (opaque, ptr)
+    voidpf opaque;
+    voidpf ptr;
+{
+    free(ptr);
+    if (opaque) return; /* make compiler happy */
+}
+
+#endif /* MY_ZCALLOC */
diff --git a/gs/zlib/zutil.h b/gs/zlib/zutil.h
new file mode 100644
index 000000000..b7d5eff81
--- /dev/null
+++ b/gs/zlib/zutil.h
@@ -0,0 +1,269 @@
+/* zutil.h -- internal interface and configuration of the compression library
+ * Copyright (C) 1995-2005 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* WARNING: this file should *not* be used by applications. It is
+   part of the implementation of the compression library and is
+   subject to change. Applications should only use zlib.h.
+ */
+
+/* @(#) $Id$ */
+
+#ifndef ZUTIL_H
+#define ZUTIL_H
+
+#define ZLIB_INTERNAL
+#include "zlib.h"
+
+#ifdef STDC
+#  ifndef _WIN32_WCE
+#    include <stddef.h>
+#  endif
+#  include <string.h>
+#  include <stdlib.h>
+#endif
+#ifdef NO_ERRNO_H
+#   ifdef _WIN32_WCE
+      /* The Microsoft C Run-Time Library for Windows CE doesn't have
+       * errno.  We define it as a global variable to simplify porting.
+       * Its value is always 0 and should not be used.  We rename it to
+       * avoid conflict with other libraries that use the same workaround.
+       */
+#     define errno z_errno
+#   endif
+    extern int errno;
+#else
+#  ifndef _WIN32_WCE
+#    include <errno.h>
+#  endif
+#endif
+
+#ifndef local
+#  define local static
+#endif
+/* compile with -Dlocal if your debugger can't find static symbols */
+
+typedef unsigned char  uch;
+typedef uch FAR uchf;
+typedef unsigned short ush;
+typedef ush FAR ushf;
+typedef unsigned long  ulg;
+
+extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
+/* (size given to avoid silly warnings with Visual C++) */
+
+#define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
+
+#define ERR_RETURN(strm,err) \
+  return (strm->msg = (char*)ERR_MSG(err), (err))
+/* To be used only when the state is known to be valid */
+
+        /* common constants */
+
+#ifndef DEF_WBITS
+#  define DEF_WBITS MAX_WBITS
+#endif
+/* default windowBits for decompression. MAX_WBITS is for compression only */
+
+#if MAX_MEM_LEVEL >= 8
+#  define DEF_MEM_LEVEL 8
+#else
+#  define DEF_MEM_LEVEL  MAX_MEM_LEVEL
+#endif
+/* default memLevel */
+
+#define STORED_BLOCK 0
+#define STATIC_TREES 1
+#define DYN_TREES    2
+/* The three kinds of block type */
+
+#define MIN_MATCH  3
+#define MAX_MATCH  258
+/* The minimum and maximum match lengths */
+
+#define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
+
+        /* target dependencies */
+
+#if defined(MSDOS) || (defined(WINDOWS) && !defined(WIN32))
+#  define OS_CODE  0x00
+#  if defined(__TURBOC__) || defined(__BORLANDC__)
+#    if(__STDC__ == 1) && (defined(__LARGE__) || defined(__COMPACT__))
+       /* Allow compilation with ANSI keywords only enabled */
+       void _Cdecl farfree( void *block );
+       void *_Cdecl farmalloc( unsigned long nbytes );
+#    else
+#      include <alloc.h>
+#    endif
+#  else /* MSC or DJGPP */
+#    include <malloc.h>
+#  endif
+#endif
+
+#ifdef AMIGA
+#  define OS_CODE  0x01
+#endif
+
+#if defined(VAXC) || defined(VMS)
+#  define OS_CODE  0x02
+#  define F_OPEN(name, mode) \
+     fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
+#endif
+
+#if defined(ATARI) || defined(atarist)
+#  define OS_CODE  0x05
+#endif
+
+#ifdef OS2
+#  define OS_CODE  0x06
+#  ifdef M_I86
+     #include <malloc.h>
+#  endif
+#endif
+
+#if defined(MACOS) || defined(TARGET_OS_MAC)
+#  define OS_CODE  0x07
+#  if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
+#    include <unix.h> /* for fdopen */
+#  else
+#    ifndef fdopen
+#      define fdopen(fd,mode) NULL /* No fdopen() */
+#    endif
+#  endif
+#endif
+
+#ifdef TOPS20
+#  define OS_CODE  0x0a
+#endif
+
+#ifdef WIN32
+#  ifndef __CYGWIN__  /* Cygwin is Unix, not Win32 */
+#    define OS_CODE  0x0b
+#  endif
+#endif
+
+#ifdef __50SERIES /* Prime/PRIMOS */
+#  define OS_CODE  0x0f
+#endif
+
+#if defined(_BEOS_) || defined(RISCOS)
+#  define fdopen(fd,mode) NULL /* No fdopen() */
+#endif
+
+#if (defined(_MSC_VER) && (_MSC_VER > 600))
+#  if defined(_WIN32_WCE)
+#    define fdopen(fd,mode) NULL /* No fdopen() */
+#    ifndef _PTRDIFF_T_DEFINED
+       typedef int ptrdiff_t;
+#      define _PTRDIFF_T_DEFINED
+#    endif
+#  else
+#    define fdopen(fd,type)  _fdopen(fd,type)
+#  endif
+#endif
+
+        /* common defaults */
+
+#ifndef OS_CODE
+#  define OS_CODE  0x03  /* assume Unix */
+#endif
+
+#ifndef F_OPEN
+#  define F_OPEN(name, mode) fopen((name), (mode))
+#endif
+
+         /* functions */
+
+#if defined(STDC99) || (defined(__TURBOC__) && __TURBOC__ >= 0x550)
+#  ifndef HAVE_VSNPRINTF
+#    define HAVE_VSNPRINTF
+#  endif
+#endif
+#if defined(__CYGWIN__)
+#  ifndef HAVE_VSNPRINTF
+#    define HAVE_VSNPRINTF
+#  endif
+#endif
+#ifndef HAVE_VSNPRINTF
+#  ifdef MSDOS
+     /* vsnprintf may exist on some MS-DOS compilers (DJGPP?),
+        but for now we just assume it doesn't. */
+#    define NO_vsnprintf
+#  endif
+#  ifdef __TURBOC__
+#    define NO_vsnprintf
+#  endif
+#  ifdef WIN32
+     /* In Win32, vsnprintf is available as the "non-ANSI" _vsnprintf. */
+#    if !defined(vsnprintf) && !defined(NO_vsnprintf)
+#      define vsnprintf _vsnprintf
+#    endif
+#  endif
+#  ifdef __SASC
+#    define NO_vsnprintf
+#  endif
+#endif
+#ifdef VMS
+#  define NO_vsnprintf
+#endif
+
+#if defined(pyr)
+#  define NO_MEMCPY
+#endif
+#if defined(SMALL_MEDIUM) && !defined(_MSC_VER) && !defined(__SC__)
+ /* Use our own functions for small and medium model with MSC <= 5.0.
+  * You may have to use the same strategy for Borland C (untested).
+  * The __SC__ check is for Symantec.
+  */
+#  define NO_MEMCPY
+#endif
+#if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
+#  define HAVE_MEMCPY
+#endif
+#ifdef HAVE_MEMCPY
+#  ifdef SMALL_MEDIUM /* MSDOS small or medium model */
+#    define zmemcpy _fmemcpy
+#    define zmemcmp _fmemcmp
+#    define zmemzero(dest, len) _fmemset(dest, 0, len)
+#  else
+#    define zmemcpy memcpy
+#    define zmemcmp memcmp
+#    define zmemzero(dest, len) memset(dest, 0, len)
+#  endif
+#else
+   extern void zmemcpy  OF((Bytef* dest, const Bytef* source, uInt len));
+   extern int  zmemcmp  OF((const Bytef* s1, const Bytef* s2, uInt len));
+   extern void zmemzero OF((Bytef* dest, uInt len));
+#endif
+
+/* Diagnostic functions */
+#ifdef DEBUG
+#  include <stdio.h>
+   extern int z_verbose;
+   extern void z_error    OF((char *m));
+#  define Assert(cond,msg) {if(!(cond)) z_error(msg);}
+#  define Trace(x) {if (z_verbose>=0) fprintf x ;}
+#  define Tracev(x) {if (z_verbose>0) fprintf x ;}
+#  define Tracevv(x) {if (z_verbose>1) fprintf x ;}
+#  define Tracec(c,x) {if (z_verbose>0 && (c)) fprintf x ;}
+#  define Tracecv(c,x) {if (z_verbose>1 && (c)) fprintf x ;}
+#else
+#  define Assert(cond,msg)
+#  define Trace(x)
+#  define Tracev(x)
+#  define Tracevv(x)
+#  define Tracec(c,x)
+#  define Tracecv(c,x)
+#endif
+
+
+voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size));
+void   zcfree  OF((voidpf opaque, voidpf ptr));
+
+#define ZALLOC(strm, items, size) \
+           (*((strm)->zalloc))((strm)->opaque, (items), (size))
+#define ZFREE(strm, addr)  (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
+#define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
+
+#endif /* ZUTIL_H */