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-ChangeLog for PCRE
-------------------
-
-Version 6.2 01-Aug-05
----------------------
-
- 1. There was no test for integer overflow of quantifier values. A construction
- such as {1111111111111111} would give undefined results. What is worse, if
- a minimum quantifier for a parenthesized subpattern overflowed and became
- negative, the calculation of the memory size went wrong. This could have
- led to memory overwriting.
-
- 2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
-
- 3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
- operating environments where this matters.
-
- 4. Applied Giuseppe Maxia's patch to add additional features for controlling
- PCRE options from within the C++ wrapper.
-
- 5. Named capturing subpatterns were not being correctly counted when a pattern
- was compiled. This caused two problems: (a) If there were more than 100
- such subpatterns, the calculation of the memory needed for the whole
- compiled pattern went wrong, leading to an overflow error. (b) Numerical
- back references of the form \12, where the number was greater than 9, were
- not recognized as back references, even though there were sufficient
- previous subpatterns.
-
- 6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
- versions of gcc, e.g. 2.95.4.
-
-
-Version 6.1 21-Jun-05
----------------------
-
- 1. There was one reference to the variable "posix" in pcretest.c that was not
- surrounded by "#if !defined NOPOSIX".
-
- 2. Make it possible to compile pcretest without DFA support, UTF8 support, or
- the cross-check on the old pcre_info() function, for the benefit of the
- cut-down version of PCRE that is currently imported into Exim.
-
- 3. A (silly) pattern starting with (?i)(?-i) caused an internal space
- allocation error. I've done the easy fix, which wastes 2 bytes for sensible
- patterns that start (?i) but I don't think that matters. The use of (?i) is
- just an example; this all applies to the other options as well.
-
- 4. Since libtool seems to echo the compile commands it is issuing, the output
- from "make" can be reduced a bit by putting "@" in front of each libtool
- compile command.
-
- 5. Patch from the folks at Google for configure.in to be a bit more thorough
- in checking for a suitable C++ installation before trying to compile the
- C++ stuff. This should fix a reported problem when a compiler was present,
- but no suitable headers.
-
- 6. The man pages all had just "PCRE" as their title. I have changed them to
- be the relevant file name. I have also arranged that these names are
- retained in the file doc/pcre.txt, which is a concatenation in text format
- of all the man pages except the little individual ones for each function.
-
- 7. The NON-UNIX-USE file had not been updated for the different set of source
- files that come with release 6. I also added a few comments about the C++
- wrapper.
-
-
-Version 6.0 07-Jun-05
----------------------
-
- 1. Some minor internal re-organization to help with my DFA experiments.
-
- 2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
- didn't matter for the library itself when fully configured, but did matter
- when compiling without UCP support, or within Exim, where the ucp files are
- not imported.
-
- 3. Refactoring of the library code to split up the various functions into
- different source modules. The addition of the new DFA matching code (see
- below) to a single monolithic source would have made it really too
- unwieldy, quite apart from causing all the code to be include in a
- statically linked application, when only some functions are used. This is
- relevant even without the DFA addition now that patterns can be compiled in
- one application and matched in another.
-
- The downside of splitting up is that there have to be some external
- functions and data tables that are used internally in different modules of
- the library but which are not part of the API. These have all had their
- names changed to start with "_pcre_" so that they are unlikely to clash
- with other external names.
-
- 4. Added an alternate matching function, pcre_dfa_exec(), which matches using
- a different (DFA) algorithm. Although it is slower than the original
- function, it does have some advantages for certain types of matching
- problem.
-
- 5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
- including restarting after a partial match.
-
- 6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
- defined when compiling for Windows was sent to me. I have put it into the
- code, though I have no means of testing or verifying it.
-
- 7. Added the pcre_refcount() auxiliary function.
-
- 8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
- match before or at the first newline in the subject string. In pcretest,
- the /f option on a pattern can be used to set this.
-
- 9. A repeated \w when used in UTF-8 mode with characters greater than 256
- would behave wrongly. This has been present in PCRE since release 4.0.
-
-10. A number of changes to the pcregrep command:
-
- (a) Refactored how -x works; insert ^(...)$ instead of setting
- PCRE_ANCHORED and checking the length, in preparation for adding
- something similar for -w.
-
- (b) Added the -w (match as a word) option.
-
- (c) Refactored the way lines are read and buffered so as to have more
- than one at a time available.
-
- (d) Implemented a pcregrep test script.
-
- (e) Added the -M (multiline match) option. This allows patterns to match
- over several lines of the subject. The buffering ensures that at least
- 8K, or the rest of the document (whichever is the shorter) is available
- for matching (and similarly the previous 8K for lookbehind assertions).
-
- (f) Changed the --help output so that it now says
-
- -w, --word-regex(p)
-
- instead of two lines, one with "regex" and the other with "regexp"
- because that confused at least one person since the short forms are the
- same. (This required a bit of code, as the output is generated
- automatically from a table. It wasn't just a text change.)
-
- (g) -- can be used to terminate pcregrep options if the next thing isn't an
- option but starts with a hyphen. Could be a pattern or a path name
- starting with a hyphen, for instance.
-
- (h) "-" can be given as a file name to represent stdin.
-
- (i) When file names are being printed, "(standard input)" is used for
- the standard input, for compatibility with GNU grep. Previously
- "<stdin>" was used.
-
- (j) The option --label=xxx can be used to supply a name to be used for
- stdin when file names are being printed. There is no short form.
-
- (k) Re-factored the options decoding logic because we are going to add
- two more options that take data. Such options can now be given in four
- different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
-
- (l) Added the -A, -B, and -C options for requesting that lines of context
- around matches be printed.
-
- (m) Added the -L option to print the names of files that do not contain
- any matching lines, that is, the complement of -l.
-
- (n) The return code is 2 if any file cannot be opened, but pcregrep does
- continue to scan other files.
-
- (o) The -s option was incorrectly implemented. For compatibility with other
- greps, it now suppresses the error message for a non-existent or non-
- accessible file (but not the return code). There is a new option called
- -q that suppresses the output of matching lines, which was what -s was
- previously doing.
-
- (p) Added --include and --exclude options to specify files for inclusion
- and exclusion when recursing.
-
-11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
- Hopefully, it now does.
-
-12. Missing cast in pcre_study().
-
-13. Added an "uninstall" target to the makefile.
-
-14. Replaced "extern" in the function prototypes in Makefile.in with
- "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
- world, but is set differently for Windows.
-
-15. Added a second compiling function called pcre_compile2(). The only
- difference is that it has an extra argument, which is a pointer to an
- integer error code. When there is a compile-time failure, this is set
- non-zero, in addition to the error test pointer being set to point to an
- error message. The new argument may be NULL if no error number is required
- (but then you may as well call pcre_compile(), which is now just a
- wrapper). This facility is provided because some applications need a
- numeric error indication, but it has also enabled me to tidy up the way
- compile-time errors are handled in the POSIX wrapper.
-
-16. Added VPATH=.libs to the makefile; this should help when building with one
- prefix path and installing with another. (Or so I'm told by someone who
- knows more about this stuff than I do.)
-
-17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
- passes PCRE_DOTALL to the pcre_compile() function, making the "." character
- match everything, including newlines. This is not POSIX-compatible, but
- somebody wanted the feature. From pcretest it can be activated by using
- both the P and the s flags.
-
-18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
-
-19. libpcre.pc was being incorrectly installed as executable.
-
-20. A couple of places in pcretest check for end-of-line by looking for '\n';
- it now also looks for '\r' so that it will work unmodified on Windows.
-
-21. Added Google's contributed C++ wrapper to the distribution.
-
-22. Added some untidy missing memory free() calls in pcretest, to keep
- Electric Fence happy when testing.
-
-
-
-Version 5.0 13-Sep-04
----------------------
-
- 1. Internal change: literal characters are no longer packed up into items
- containing multiple characters in a single byte-string. Each character
- is now matched using a separate opcode. However, there may be more than one
- byte in the character in UTF-8 mode.
-
- 2. The pcre_callout_block structure has two new fields: pattern_position and
- next_item_length. These contain the offset in the pattern to the next match
- item, and its length, respectively.
-
- 3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
- insertion of callouts before each pattern item. Added the /C option to
- pcretest to make use of this.
-
- 4. On the advice of a Windows user, the lines
-
- #if defined(_WIN32) || defined(WIN32)
- _setmode( _fileno( stdout ), 0x8000 );
- #endif /* defined(_WIN32) || defined(WIN32) */
-
- have been added to the source of pcretest. This apparently does useful
- magic in relation to line terminators.
-
- 5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
- for the benefit of those environments where the "b" makes a difference.
-
- 6. The icc compiler has the same options as gcc, but "configure" doesn't seem
- to know about it. I have put a hack into configure.in that adds in code
- to set GCC=yes if CC=icc. This seems to end up at a point in the
- generated configure script that is early enough to affect the setting of
- compiler options, which is what is needed, but I have no means of testing
- whether it really works. (The user who reported this had patched the
- generated configure script, which of course I cannot do.)
-
- LATER: After change 22 below (new libtool files), the configure script
- seems to know about icc (and also ecc). Therefore, I have commented out
- this hack in configure.in.
-
- 7. Added support for pkg-config (2 patches were sent in).
-
- 8. Negated POSIX character classes that used a combination of internal tables
- were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
- [[:^ascii]]. Typically, they would match almost any characters. The other
- POSIX classes were not broken in this way.
-
- 9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
- to find the match, as PCRE was deluded into thinking that the match had to
- start at the start point or following a newline. The same bug applied to
- patterns with negative forward assertions or any backward assertions
- preceding ".*" at the start, unless the pattern required a fixed first
- character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
-
-10. In UTF-8 mode, when moving forwards in the subject after a failed match
- starting at the last subject character, bytes beyond the end of the subject
- string were read.
-
-11. Renamed the variable "class" as "classbits" to make life easier for C++
- users. (Previously there was a macro definition, but it apparently wasn't
- enough.)
-
-12. Added the new field "tables" to the extra data so that tables can be passed
- in at exec time, or the internal tables can be re-selected. This allows
- a compiled regex to be saved and re-used at a later time by a different
- program that might have everything at different addresses.
-
-13. Modified the pcre-config script so that, when run on Solaris, it shows a
- -R library as well as a -L library.
-
-14. The debugging options of pcretest (-d on the command line or D on a
- pattern) showed incorrect output for anything following an extended class
- that contained multibyte characters and which was followed by a quantifier.
-
-15. Added optional support for general category Unicode character properties
- via the \p, \P, and \X escapes. Unicode property support implies UTF-8
- support. It adds about 90K to the size of the library. The meanings of the
- inbuilt class escapes such as \d and \s have NOT been changed.
-
-16. Updated pcredemo.c to include calls to free() to release the memory for the
- compiled pattern.
-
-17. The generated file chartables.c was being created in the source directory
- instead of in the building directory. This caused the build to fail if the
- source directory was different from the building directory, and was
- read-only.
-
-18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
- file. No doubt somebody will tell me if they don't make sense... Also added
- Dan Mooney's comments about building on OpenVMS.
-
-19. Added support for partial matching via the PCRE_PARTIAL option for
- pcre_exec() and the \P data escape in pcretest.
-
-20. Extended pcretest with 3 new pattern features:
-
- (i) A pattern option of the form ">rest-of-line" causes pcretest to
- write the compiled pattern to the file whose name is "rest-of-line".
- This is a straight binary dump of the data, with the saved pointer to
- the character tables forced to be NULL. The study data, if any, is
- written too. After writing, pcretest reads a new pattern.
-
- (ii) If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
- compiled pattern from the given file. There must not be any
- occurrences of "<" in the file name (pretty unlikely); if there are,
- pcretest will instead treat the initial "<" as a pattern delimiter.
- After reading in the pattern, pcretest goes on to read data lines as
- usual.
-
- (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
- and 16-bit fields in a compiled pattern, to simulate a pattern that
- was compiled on a host of opposite endianness.
-
-21. The pcre-exec() function can now cope with patterns that were compiled on
- hosts of opposite endianness, with this restriction:
-
- As for any compiled expression that is saved and used later, the tables
- pointer field cannot be preserved; the extra_data field in the arguments
- to pcre_exec() should be used to pass in a tables address if a value
- other than the default internal tables were used at compile time.
-
-22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
- now diagnosed as an error. Previously, most of the time, a negative number
- would have been treated as zero, but if in addition "ovector" was passed as
- NULL, a crash could occur.
-
-23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
- new versions from the libtool 1.5 distribution (the last one is a copy of
- a file called libtool.m4). This seems to have fixed the need to patch
- "configure" to support Darwin 1.3 (which I used to do). However, I still
- had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
- workstation).
-
-24. Changed the PCRE licence to be the more standard "BSD" licence.
-
-
-Version 4.5 01-Dec-03
----------------------
-
- 1. There has been some re-arrangement of the code for the match() function so
- that it can be compiled in a version that does not call itself recursively.
- Instead, it keeps those local variables that need separate instances for
- each "recursion" in a frame on the heap, and gets/frees frames whenever it
- needs to "recurse". Keeping track of where control must go is done by means
- of setjmp/longjmp. The whole thing is implemented by a set of macros that
- hide most of the details from the main code, and operates only if
- NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
- "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
- operating.
-
- To make it easier for callers to provide specially tailored get/free
- functions for this usage, two new functions, pcre_stack_malloc, and
- pcre_stack_free, are used. They are always called in strict stacking order,
- and the size of block requested is always the same.
-
- The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
- PCRE has been compiled to use the stack or the heap for recursion. The
- -C option of pcretest uses this to show which version is compiled.
-
- A new data escape \S, is added to pcretest; it causes the amounts of store
- obtained and freed by both kinds of malloc/free at match time to be added
- to the output.
-
- 2. Changed the locale test to use "fr_FR" instead of "fr" because that's
- what's available on my current Linux desktop machine.
-
- 3. When matching a UTF-8 string, the test for a valid string at the start has
- been extended. If start_offset is not zero, PCRE now checks that it points
- to a byte that is the start of a UTF-8 character. If not, it returns
- PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
- this is necessary because there may be backward assertions in the pattern.
- When matching the same subject several times, it may save resources to use
- PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
-
- 4. The code for checking the validity of UTF-8 strings has been tightened so
- that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
- containing "overlong sequences".
-
- 5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
- I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
- should have been "&", but it just so happened that all the cases this let
- through by mistake were picked up later in the function.
-
- 6. I had used a variable called "isblank" - this is a C99 function, causing
- some compilers to warn. To avoid this, I renamed it (as "blankclass").
-
- 7. Cosmetic: (a) only output another newline at the end of pcretest if it is
- prompting; (b) run "./pcretest /dev/null" at the start of the test script
- so the version is shown; (c) stop "make test" echoing "./RunTest".
-
- 8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
-
- 9. The prototype for memmove() for systems that don't have it was using
- size_t, but the inclusion of the header that defines size_t was later. I've
- moved the #includes for the C headers earlier to avoid this.
-
-10. Added some adjustments to the code to make it easier to compiler on certain
- special systems:
-
- (a) Some "const" qualifiers were missing.
- (b) Added the macro EXPORT before all exported functions; by default this
- is defined to be empty.
- (c) Changed the dftables auxiliary program (that builds chartables.c) so
- that it reads its output file name as an argument instead of writing
- to the standard output and assuming this can be redirected.
-
-11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
- class containing characters with values greater than 255, PCRE compilation
- went into a loop.
-
-12. A recursive reference to a subpattern that was within another subpattern
- that had a minimum quantifier of zero caused PCRE to crash. For example,
- (x(y(?2))z)? provoked this bug with a subject that got as far as the
- recursion. If the recursively-called subpattern itself had a zero repeat,
- that was OK.
-
-13. In pcretest, the buffer for reading a data line was set at 30K, but the
- buffer into which it was copied (for escape processing) was still set at
- 1024, so long lines caused crashes.
-
-14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
- "internal error: code overflow...". This applied to any character class
- that was followed by a possessive quantifier.
-
-15. Modified the Makefile to add libpcre.la as a prerequisite for
- libpcreposix.la because I was told this is needed for a parallel build to
- work.
-
-16. If a pattern that contained .* following optional items at the start was
- studied, the wrong optimizing data was generated, leading to matching
- errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
- matching string must start with a or b or c. The correct conclusion for
- this pattern is that a match can start with any character.
-
-
-Version 4.4 13-Aug-03
----------------------
-
- 1. In UTF-8 mode, a character class containing characters with values between
- 127 and 255 was not handled correctly if the compiled pattern was studied.
- In fixing this, I have also improved the studying algorithm for such
- classes (slightly).
-
- 2. Three internal functions had redundant arguments passed to them. Removal
- might give a very teeny performance improvement.
-
- 3. Documentation bug: the value of the capture_top field in a callout is *one
- more than* the number of the hightest numbered captured substring.
-
- 4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
- in incorrectly linking with a previously installed version. They now link
- explicitly with libpcre.la.
-
- 5. configure.in no longer needs to recognize Cygwin specially.
-
- 6. A problem in pcre.in for Windows platforms is fixed.
-
- 7. If a pattern was successfully studied, and the -d (or /D) flag was given to
- pcretest, it used to include the size of the study block as part of its
- output. Unfortunately, the structure contains a field that has a different
- size on different hardware architectures. This meant that the tests that
- showed this size failed. As the block is currently always of a fixed size,
- this information isn't actually particularly useful in pcretest output, so
- I have just removed it.
-
- 8. Three pre-processor statements accidentally did not start in column 1.
- Sadly, there are *still* compilers around that complain, even though
- standard C has not required this for well over a decade. Sigh.
-
- 9. In pcretest, the code for checking callouts passed small integers in the
- callout_data field, which is a void * field. However, some picky compilers
- complained about the casts involved for this on 64-bit systems. Now
- pcretest passes the address of the small integer instead, which should get
- rid of the warnings.
-
-10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
- both compile and run time, and gives an error if an invalid UTF-8 sequence
- is found. There is a option for disabling this check in cases where the
- string is known to be correct and/or the maximum performance is wanted.
-
-11. In response to a bug report, I changed one line in Makefile.in from
-
- -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
- to
- -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
-
- to look similar to other lines, but I have no way of telling whether this
- is the right thing to do, as I do not use Windows. No doubt I'll get told
- if it's wrong...
-
-
-Version 4.3 21-May-03
----------------------
-
-1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
- Makefile.
-
-2. Some refactoring to improve the quality of the code:
-
- (i) The utf8_table... variables are now declared "const".
-
- (ii) The code for \cx, which used the "case flipping" table to upper case
- lower case letters, now just substracts 32. This is ASCII-specific,
- but the whole concept of \cx is ASCII-specific, so it seems
- reasonable.
-
- (iii) PCRE was using its character types table to recognize decimal and
- hexadecimal digits in the pattern. This is silly, because it handles
- only 0-9, a-f, and A-F, but the character types table is locale-
- specific, which means strange things might happen. A private
- table is now used for this - though it costs 256 bytes, a table is
- much faster than multiple explicit tests. Of course, the standard
- character types table is still used for matching digits in subject
- strings against \d.
-
- (iv) Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
- ending in _t are). So I've renamed it as ESC_tee.
-
-3. The first argument for regexec() in the POSIX wrapper should have been
- defined as "const".
-
-4. Changed pcretest to use malloc() for its buffers so that they can be
- Electric Fenced for debugging.
-
-5. There were several places in the code where, in UTF-8 mode, PCRE would try
- to read one or more bytes before the start of the subject string. Often this
- had no effect on PCRE's behaviour, but in some circumstances it could
- provoke a segmentation fault.
-
-6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
- to try to read one or more bytes before the start of the subject string.
-
-7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
- UTF-8 support could misbehave in various ways if the subject string
- contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
- area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
- back over UTF-8 characters.)
-
-
-Version 4.2 14-Apr-03
----------------------
-
-1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
-
-2. Changes to the building process, supplied by Ronald Landheer-Cieslak
- [ON_WINDOWS]: new variable, "#" on non-Windows platforms
- [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
- [WIN_PREFIX]: new variable, "cyg" for Cygwin
- * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
- and BUILD_EXEEXT
- Note: automatic setting of the BUILD variables is not yet working
- set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
- compile-time but not at link-time
- [LINK]: use for linking executables only
- make different versions for Windows and non-Windows
- [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
- libraries
- [LINK_FOR_BUILD]: new variable
- [OBJEXT]: use throughout
- [EXEEXT]: use throughout
- <winshared>: new target
- <wininstall>: new target
- <dftables.o>: use native compiler
- <dftables>: use native linker
- <install>: handle Windows platform correctly
- <clean>: ditto
- <check>: ditto
- copy DLL to top builddir before testing
-
- As part of these changes, -no-undefined was removed again. This was reported
- to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
- in any case.
-
-3. Some tidies to get rid of compiler warnings:
-
- . In the match_data structure, match_limit was an unsigned long int, whereas
- match_call_count was an int. I've made them both unsigned long ints.
-
- . In pcretest the fact that a const uschar * doesn't automatically cast to
- a void * provoked a warning.
-
- . Turning on some more compiler warnings threw up some "shadow" variables
- and a few more missing casts.
-
-4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
- option, a class that contained a single character with a value between 128
- and 255 (e.g. /[\xFF]/) caused PCRE to crash.
-
-5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
- option, a class that contained several characters, but with at least one
- whose value was between 128 and 255 caused PCRE to crash.
-
-
-Version 4.1 12-Mar-03
----------------------
-
-1. Compiling with gcc -pedantic found a couple of places where casts were
-needed, and a string in dftables.c that was longer than standard compilers are
-required to support.
-
-2. Compiling with Sun's compiler found a few more places where the code could
-be tidied up in order to avoid warnings.
-
-3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
-first of these names is deprecated in the latest Autoconf in favour of the name
-CC_FOR_BUILD, because "host" is typically used to mean the system on which the
-compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
-analogy I have changed it to CFLAGS_FOR_BUILD.
-
-4. Added -no-undefined to the linking command in the Makefile, because this is
-apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
-linking step for the pcreposix library.
-
-5. PCRE was failing to diagnose the case of two named groups with the same
-name.
-
-6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
-literal character that is needed in the subject for a match, and scans along to
-ensure that it is present before embarking on the full matching process. This
-saves time in cases of nested unlimited repeats that are never going to match.
-Problem: the scan can take a lot of time if the subject is very long (e.g.
-megabytes), thus penalizing straightforward matches. It is now done only if the
-amount of subject to be scanned is less than 1000 bytes.
-
-7. A lesser problem with the same optimization is that it was recording the
-first character of an anchored pattern as "needed", thus provoking a search
-right along the subject, even when the first match of the pattern was going to
-fail. The "needed" character is now not set for anchored patterns, unless it
-follows something in the pattern that is of non-fixed length. Thus, it still
-fulfils its original purpose of finding quick non-matches in cases of nested
-unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
-
-
-Version 4.0 17-Feb-03
----------------------
-
-1. If a comment in an extended regex that started immediately after a meta-item
-extended to the end of string, PCRE compiled incorrect data. This could lead to
-all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
-
-2. Moved to autoconf 2.53 and libtool 1.4.2.
-
-3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
-the special perltest8 script is no longer needed - all the tests can be run
-from a single perltest script.
-
-4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
-by \s. It has now been removed in PCRE. This means it isn't recognized as
-whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
-class [:space:] *does* include VT, thereby creating a mess.
-
-5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
-space and tab.
-
-6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
-its new features into the main test script, reducing the number of scripts.
-
-7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
-were backward compatible, and made the (?i) apply to the whole pattern, as if
-/i were given. Now it behaves more logically, and applies the option setting
-only to what follows. PCRE has been changed to follow suit. However, if it
-finds options settings right at the start of the pattern, it extracts them into
-the global options, as before. Thus, they show up in the info data.
-
-8. Added support for the \Q...\E escape sequence. Characters in between are
-treated as literals. This is slightly different from Perl in that $ and @ are
-also handled as literals inside the quotes. In Perl, they will cause variable
-interpolation. Note the following examples:
-
- Pattern PCRE matches Perl matches
-
- \Qabc$xyz\E abc$xyz abc followed by the contents of $xyz
- \Qabc\$xyz\E abc\$xyz abc\$xyz
- \Qabc\E\$\Qxyz\E abc$xyz abc$xyz
-
-For compatibility with Perl, \Q...\E sequences are recognized inside character
-classes as well as outside them.
-
-9. Re-organized 3 code statements in pcretest to avoid "overflow in
-floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
-(size_t) cast to one statement in pcretest and one in pcreposix to avoid
-signed/unsigned warnings.
-
-10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
-option for pcretest, so I've replaced it by a simple function that does just
-that job.
-
-11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
-"pcregrep -".
-
-12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
-Java package. This provides some syntactic sugar for simple cases of what my
-documentation calls "once-only subpatterns". A pattern such as x*+ is the same
-as (?>x*). In other words, if what is inside (?>...) is just a single repeated
-item, you can use this simplified notation. Note that only makes sense with
-greedy quantifiers. Consequently, the use of the possessive quantifier forces
-greediness, whatever the setting of the PCRE_UNGREEDY option.
-
-13. A change of greediness default within a pattern was not taking effect at
-the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
-subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
-was abstracted outside.
-
-14. PCRE now supports the \G assertion. It is true when the current matching
-position is at the start point of the match. This differs from \A when the
-starting offset is non-zero. Used with the /g option of pcretest (or similar
-code), it works in the same way as it does for Perl's /g option. If all
-alternatives of a regex begin with \G, the expression is anchored to the start
-match position, and the "anchored" flag is set in the compiled expression.
-
-15. Some bugs concerning the handling of certain option changes within patterns
-have been fixed. These applied to options other than (?ims). For example,
-"a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
-been the other way round. Some of this was related to change 7 above.
-
-16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
-features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
-and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
-POSIX classes only within a class (e.g. /[[:alpha:]]/).
-
-17. Added support for Perl's \C escape. This matches one byte, even in UTF8
-mode. Unlike ".", it always matches newline, whatever the setting of
-PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
-assertions. Perl allows it, but it doesn't (in general) work because it can't
-calculate the length of the lookbehind. At least, that's the case for Perl
-5.8.0 - I've been told they are going to document that it doesn't work in
-future.
-
-18. Added an error diagnosis for escapes that PCRE does not support: these are
-\L, \l, \N, \P, \p, \U, \u, and \X.
-
-19. Although correctly diagnosing a missing ']' in a character class, PCRE was
-reading past the end of the pattern in cases such as /[abcd/.
-
-20. PCRE was getting more memory than necessary for patterns with classes that
-contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
-
-21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
-compiling PCRE for use with Virtual Pascal.
-
-22. Small fix to the Makefile to make it work properly if the build is done
-outside the source tree.
-
-23. Added a new extension: a condition to go with recursion. If a conditional
-subpattern starts with (?(R) the "true" branch is used if recursion has
-happened, whereas the "false" branch is used only at the top level.
-
-24. When there was a very long string of literal characters (over 255 bytes
-without UTF support, over 250 bytes with UTF support), the computation of how
-much memory was required could be incorrect, leading to segfaults or other
-strange effects.
-
-25. PCRE was incorrectly assuming anchoring (either to start of subject or to
-start of line for a non-DOTALL pattern) when a pattern started with (.*) and
-there was a subsequent back reference to those brackets. This meant that, for
-example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
-possible to check for precisely this case. All we can do is abandon the
-optimization if .* occurs inside capturing brackets when there are any back
-references whatsoever. (See below for a better fix that came later.)
-
-26. The handling of the optimization for finding the first character of a
-non-anchored pattern, and for finding a character that is required later in the
-match were failing in some cases. This didn't break the matching; it just
-failed to optimize when it could. The way this is done has been re-implemented.
-
-27. Fixed typo in error message for invalid (?R item (it said "(?p").
-
-28. Added a new feature that provides some of the functionality that Perl
-provides with (?{...}). The facility is termed a "callout". The way it is done
-in PCRE is for the caller to provide an optional function, by setting
-pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
-global variable. By default it is unset, which disables all calling out. To get
-the function called, the regex must include (?C) at appropriate points. This
-is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
-This provides a means of identifying different callout points. When PCRE
-reaches such a point in the regex, if pcre_callout has been set, the external
-function is called. It is provided with data in a structure called
-pcre_callout_block, which is defined in pcre.h. If the function returns 0,
-matching continues; if it returns a non-zero value, the match at the current
-point fails. However, backtracking will occur if possible. [This was changed
-later and other features added - see item 49 below.]
-
-29. pcretest is upgraded to test the callout functionality. It provides a
-callout function that displays information. By default, it shows the start of
-the match and the current position in the text. There are some new data escapes
-to vary what happens:
-
- \C+ in addition, show current contents of captured substrings
- \C- do not supply a callout function
- \C!n return 1 when callout number n is reached
- \C!n!m return 1 when callout number n is reached for the mth time
-
-30. If pcregrep was called with the -l option and just a single file name, it
-output "<stdin>" if a match was found, instead of the file name.
-
-31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
-slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
-pcre_exec(). This saves a malloc/free per call. The default value of
-POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
-when configuring.
-
-32. The default maximum size of a compiled pattern is 64K. There have been a
-few cases of people hitting this limit. The code now uses macros to handle the
-storing of links as offsets within the compiled pattern. It defaults to 2-byte
-links, but this can be changed to 3 or 4 bytes by --with-link-size when
-configuring. Tests 2 and 5 work only with 2-byte links because they output
-debugging information about compiled patterns.
-
-33. Internal code re-arrangements:
-
-(a) Moved the debugging function for printing out a compiled regex into
- its own source file (printint.c) and used #include to pull it into
- pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
- separate copies.
-
-(b) Defined the list of op-code names for debugging as a macro in
- internal.h so that it is next to the definition of the opcodes.
-
-(c) Defined a table of op-code lengths for simpler skipping along compiled
- code. This is again a macro in internal.h so that it is next to the
- definition of the opcodes.
-
-34. Added support for recursive calls to individual subpatterns, along the
-lines of Robin Houston's patch (but implemented somewhat differently).
-
-35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
-allow it to read and process whole directories in Win32. This code was
-contributed by Lionel Fourquaux; it has not been tested by me.
-
-36. Added support for named subpatterns. The Python syntax (?P<name>...) is
-used to name a group. Names consist of alphanumerics and underscores, and must
-be unique. Back references use the syntax (?P=name) and recursive calls use
-(?P>name) which is a PCRE extension to the Python extension. Groups still have
-numbers. The function pcre_fullinfo() can be used after compilation to extract
-a name/number map. There are three relevant calls:
-
- PCRE_INFO_NAMEENTRYSIZE yields the size of each entry in the map
- PCRE_INFO_NAMECOUNT yields the number of entries
- PCRE_INFO_NAMETABLE yields a pointer to the map.
-
-The map is a vector of fixed-size entries. The size of each entry depends on
-the length of the longest name used. The first two bytes of each entry are the
-group number, most significant byte first. There follows the corresponding
-name, zero terminated. The names are in alphabetical order.
-
-37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
-case instead of 255. Making it the same both with and without UTF-8 support
-means that the same test output works with both.
-
-38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
-calling malloc() with a zero argument.
-
-39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
-optimization. I've improved things by keeping a bitmap of backreferences with
-numbers 1-31 so that if .* occurs inside capturing brackets that are not in
-fact referenced, the optimization can be applied. It is unlikely that a
-relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
-the match to follow \n) will appear inside brackets with a number greater than
-31, but if it does, any back reference > 31 suppresses the optimization.
-
-40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
-of disabling numbered capturing parentheses. Any opening parenthesis that is
-not followed by ? behaves as if it were followed by ?: but named parentheses
-can still be used for capturing (and they will acquire numbers in the usual
-way).
-
-41. Redesigned the return codes from the match() function into yes/no/error so
-that errors can be passed back from deep inside the nested calls. A malloc
-failure while inside a recursive subpattern call now causes the
-PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
-
-42. It is now possible to set a limit on the number of times the match()
-function is called in a call to pcre_exec(). This facility makes it possible to
-limit the amount of recursion and backtracking, though not in a directly
-obvious way, because the match() function is used in a number of different
-circumstances. The count starts from zero for each position in the subject
-string (for non-anchored patterns). The default limit is, for compatibility, a
-large number, namely 10 000 000. You can change this in two ways:
-
-(a) When configuring PCRE before making, you can use --with-match-limit=n
- to set a default value for the compiled library.
-
-(b) For each call to pcre_exec(), you can pass a pcre_extra block in which
- a different value is set. See 45 below.
-
-If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
-
-43. Added a new function pcre_config(int, void *) to enable run-time extraction
-of things that can be changed at compile time. The first argument specifies
-what is wanted and the second points to where the information is to be placed.
-The current list of available information is:
-
- PCRE_CONFIG_UTF8
-
-The output is an integer that is set to one if UTF-8 support is available;
-otherwise it is set to zero.
-
- PCRE_CONFIG_NEWLINE
-
-The output is an integer that it set to the value of the code that is used for
-newline. It is either LF (10) or CR (13).
-
- PCRE_CONFIG_LINK_SIZE
-
-The output is an integer that contains the number of bytes used for internal
-linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
-
- PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
-
-The output is an integer that contains the threshold above which the POSIX
-interface uses malloc() for output vectors. See item 31 above.
-
- PCRE_CONFIG_MATCH_LIMIT
-
-The output is an unsigned integer that contains the default limit of the number
-of match() calls in a pcre_exec() execution. See 42 above.
-
-44. pcretest has been upgraded by the addition of the -C option. This causes it
-to extract all the available output from the new pcre_config() function, and to
-output it. The program then exits immediately.
-
-45. A need has arisen to pass over additional data with calls to pcre_exec() in
-order to support additional features. One way would have been to define
-pcre_exec2() (for example) with extra arguments, but this would not have been
-extensible, and would also have required all calls to the original function to
-be mapped to the new one. Instead, I have chosen to extend the mechanism that
-is used for passing in "extra" data from pcre_study().
-
-The pcre_extra structure is now exposed and defined in pcre.h. It currently
-contains the following fields:
-
- flags a bitmap indicating which of the following fields are set
- study_data opaque data from pcre_study()
- match_limit a way of specifying a limit on match() calls for a specific
- call to pcre_exec()
- callout_data data for callouts (see 49 below)
-
-The flag bits are also defined in pcre.h, and are
-
- PCRE_EXTRA_STUDY_DATA
- PCRE_EXTRA_MATCH_LIMIT
- PCRE_EXTRA_CALLOUT_DATA
-
-The pcre_study() function now returns one of these new pcre_extra blocks, with
-the actual study data pointed to by the study_data field, and the
-PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
-before. That is, this change is entirely upwards-compatible and requires no
-change to existing code.
-
-If you want to pass in additional data to pcre_exec(), you can either place it
-in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
-block.
-
-46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
-data string contains the escape sequence \M, pcretest calls pcre_exec() several
-times with different match limits, until it finds the minimum value needed for
-pcre_exec() to complete. The value is then output. This can be instructive; for
-most simple matches the number is quite small, but for pathological cases it
-gets very large very quickly.
-
-47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
-returns the size of the data block pointed to by the study_data field in a
-pcre_extra block, that is, the value that was passed as the argument to
-pcre_malloc() when PCRE was getting memory in which to place the information
-created by pcre_study(). The fourth argument should point to a size_t variable.
-pcretest has been extended so that this information is shown after a successful
-pcre_study() call when information about the compiled regex is being displayed.
-
-48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
-because what follows is always an absolute path. (Later: it turns out that this
-is more than cosmetic for MinGW, because it doesn't like empty path
-components.)
-
-49. Some changes have been made to the callout feature (see 28 above):
-
-(i) A callout function now has three choices for what it returns:
-
- 0 => success, carry on matching
- > 0 => failure at this point, but backtrack if possible
- < 0 => serious error, return this value from pcre_exec()
-
- Negative values should normally be chosen from the set of PCRE_ERROR_xxx
- values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
- "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
- use by callout functions. It will never be used by PCRE itself.
-
-(ii) The pcre_extra structure (see 45 above) has a void * field called
- callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
- pcre_callout_block structure has a field of the same name. The contents of
- the field passed in the pcre_extra structure are passed to the callout
- function in the corresponding field in the callout block. This makes it
- easier to use the same callout-containing regex from multiple threads. For
- testing, the pcretest program has a new data escape
-
- \C*n pass the number n (may be negative) as callout_data
-
- If the callout function in pcretest receives a non-zero value as
- callout_data, it returns that value.
-
-50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
-there were some redundant $(CFLAGS) in commands that are now specified as
-$(LINK), which already includes $(CFLAGS).
-
-51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
-has been compiled with UTF-8 support *and* pcre_compile() has been compiled
-with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
-one-byte characters throughout. Note that case-insensitive matching applies
-only to characters whose values are less than 256. PCRE doesn't support the
-notion of cases for higher-valued characters.
-
-(i) A character class whose characters are all within 0-255 is handled as
- a bit map, and the map is inverted for negative classes. Previously, a
- character > 255 always failed to match such a class; however it should
- match if the class was a negative one (e.g. [^ab]). This has been fixed.
-
-(ii) A negated character class with a single character < 255 is coded as
- "not this character" (OP_NOT). This wasn't working properly when the test
- character was multibyte, either singly or repeated.
-
-(iii) Repeats of multibyte characters are now handled correctly in UTF-8
- mode, for example: \x{100}{2,3}.
-
-(iv) The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
- singly or repeated) now correctly test multibyte characters. However,
- PCRE doesn't recognize any characters with values greater than 255 as
- digits, spaces, or word characters. Such characters always match \D, \S,
- and \W, and never match \d, \s, or \w.
-
-(v) Classes may now contain characters and character ranges with values
- greater than 255. For example: [ab\x{100}-\x{400}].
-
-(vi) pcregrep now has a --utf-8 option (synonym -u) which makes it call
- PCRE in UTF-8 mode.
-
-52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
-PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
-retained for backwards compatibility. (Note that LASTLITERAL is also a byte
-value.)
-
-53. The single man page has become too large. I have therefore split it up into
-a number of separate man pages. These also give rise to individual HTML pages;
-these are now put in a separate directory, and there is an index.html page that
-lists them all. Some hyperlinking between the pages has been installed.
-
-54. Added convenience functions for handling named capturing parentheses.
-
-55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
-aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
-true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
-are faulted.
-
-56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
-calling configure. These values are used when compiling the dftables.c program
-which is run to generate the source of the default character tables. They
-default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
-you will need to set these values.
-
-57. Updated the building process for Windows DLL, as provided by Fred Cox.
-
-
-Version 3.9 02-Jan-02
----------------------
-
-1. A bit of extraneous text had somehow crept into the pcregrep documentation.
-
-2. If --disable-static was given, the building process failed when trying to
-build pcretest and pcregrep. (For some reason it was using libtool to compile
-them, which is not right, as they aren't part of the library.)
-
-
-Version 3.8 18-Dec-01
----------------------
-
-1. The experimental UTF-8 code was completely screwed up. It was packing the
-bytes in the wrong order. How dumb can you get?
-
-
-Version 3.7 29-Oct-01
----------------------
-
-1. In updating pcretest to check change 1 of version 3.6, I screwed up.
-This caused pcretest, when used on the test data, to segfault. Unfortunately,
-this didn't happen under Solaris 8, where I normally test things.
-
-2. The Makefile had to be changed to make it work on BSD systems, where 'make'
-doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
-isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
-this fix an hour or so after the initial 3.7 release.)
-
-
-Version 3.6 23-Oct-01
----------------------
-
-1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
-offsets passed as NULL with zero offset count.
-
-2. The config.guess and config.sub files had not been updated when I moved to
-the latest autoconf.
-
-
-Version 3.5 15-Aug-01
----------------------
-
-1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
-had been forgotten.
-
-2. By using declared but undefined structures, we can avoid using "void"
-definitions in pcre.h while keeping the internal definitions of the structures
-private.
-
-3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
-user point of view, this means that both static and shared libraries are built
-by default, but this can be individually controlled. More of the work of
-handling this static/shared cases is now inside libtool instead of PCRE's make
-file.
-
-4. The pcretest utility is now installed along with pcregrep because it is
-useful for users (to test regexs) and by doing this, it automatically gets
-relinked by libtool. The documentation has been turned into a man page, so
-there are now .1, .txt, and .html versions in /doc.
-
-5. Upgrades to pcregrep:
- (i) Added long-form option names like gnu grep.
- (ii) Added --help to list all options with an explanatory phrase.
- (iii) Added -r, --recursive to recurse into sub-directories.
- (iv) Added -f, --file to read patterns from a file.
-
-6. pcre_exec() was referring to its "code" argument before testing that
-argument for NULL (and giving an error if it was NULL).
-
-7. Upgraded Makefile.in to allow for compiling in a different directory from
-the source directory.
-
-8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
-options bits, the pointer it was passed was to an int instead of to an unsigned
-long int. This mattered only on 64-bit systems.
-
-9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
-generated) instead of pcre.in, which it its source. Also made the same change
-in several of the .c files.
-
-10. A new release of gcc defines printf() as a macro, which broke pcretest
-because it had an ifdef in the middle of a string argument for printf(). Fixed
-by using separate calls to printf().
-
-11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
-script, to force use of CR or LF instead of \n in the source. On non-Unix
-systems, the value can be set in config.h.
-
-12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
-absolute limit. Changed the text of the error message to make this clear, and
-likewise updated the man page.
-
-13. The limit of 99 on the number of capturing subpatterns has been removed.
-The new limit is 65535, which I hope will not be a "real" limit.
-
-
-Version 3.4 22-Aug-00
----------------------
-
-1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
-
-2. Diagnose condition (?(0) as an error instead of crashing on matching.
-
-
-Version 3.3 01-Aug-00
----------------------
-
-1. If an octal character was given, but the value was greater than \377, it
-was not getting masked to the least significant bits, as documented. This could
-lead to crashes in some systems.
-
-2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
-the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
-
-3. Added the functions pcre_free_substring() and pcre_free_substring_list().
-These just pass their arguments on to (pcre_free)(), but they are provided
-because some uses of PCRE bind it to non-C systems that can call its functions,
-but cannot call free() or pcre_free() directly.
-
-4. Add "make test" as a synonym for "make check". Corrected some comments in
-the Makefile.
-
-5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
-Makefile.
-
-6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
-command called pgrep for grepping around the active processes.
-
-7. Added the beginnings of support for UTF-8 character strings.
-
-8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
-RANLIB to ./ltconfig so that they are used by libtool. I think these are all
-the relevant ones. (AR is not passed because ./ltconfig does its own figuring
-out for the ar command.)
-
-
-Version 3.2 12-May-00
----------------------
-
-This is purely a bug fixing release.
-
-1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
-of ZA. This was just one example of several cases that could provoke this bug,
-which was introduced by change 9 of version 2.00. The code for breaking
-infinite loops after an iteration that matches an empty string was't working
-correctly.
-
-2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
-when matched against abbab (for example). After matching an empty string, it
-wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
-caused it to match further down the string than it should.
-
-3. The code contained an inclusion of sys/types.h. It isn't clear why this
-was there because it doesn't seem to be needed, and it causes trouble on some
-systems, as it is not a Standard C header. It has been removed.
-
-4. Made 4 silly changes to the source to avoid stupid compiler warnings that
-were reported on the Macintosh. The changes were from
-
- while ((c = *(++ptr)) != 0 && c != '\n');
-to
- while ((c = *(++ptr)) != 0 && c != '\n') ;
-
-Totally extraordinary, but if that's what it takes...
-
-5. PCRE is being used in one environment where neither memmove() nor bcopy() is
-available. Added HAVE_BCOPY and an autoconf test for it; if neither
-HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
-assumes the way PCRE uses memmove() (always moving upwards).
-
-6. PCRE is being used in one environment where strchr() is not available. There
-was only one use in pcre.c, and writing it out to avoid strchr() probably gives
-faster code anyway.
-
-
-Version 3.1 09-Feb-00
----------------------
-
-The only change in this release is the fixing of some bugs in Makefile.in for
-the "install" target:
-
-(1) It was failing to install pcreposix.h.
-
-(2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.
-
-
-Version 3.0 01-Feb-00
----------------------
-
-1. Add support for the /+ modifier to perltest (to output $` like it does in
-pcretest).
-
-2. Add support for the /g modifier to perltest.
-
-3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
-matches null strings.
-
-4. Fix perltest so that it doesn't do unwanted things when fed an empty
-pattern. Perl treats empty patterns specially - it reuses the most recent
-pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
-effect.
-
-5. The POSIX interface was broken in that it was just handing over the POSIX
-captured string vector to pcre_exec(), but (since release 2.00) PCRE has
-required a bigger vector, with some working space on the end. This means that
-the POSIX wrapper now has to get and free some memory, and copy the results.
-
-6. Added some simple autoconf support, placing the test data and the
-documentation in separate directories, re-organizing some of the
-information files, and making it build pcre-config (a GNU standard). Also added
-libtool support for building PCRE as a shared library, which is now the
-default.
-
-7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
-09 are not valid octal constants. Single digits will be used for minor values
-less than 10.
-
-8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
-existing programs that set these in the POSIX interface can use PCRE without
-modification.
-
-9. Added a new function, pcre_fullinfo() with an extensible interface. It can
-return all that pcre_info() returns, plus additional data. The pcre_info()
-function is retained for compatibility, but is considered to be obsolete.
-
-10. Added experimental recursion feature (?R) to handle one common case that
-Perl 5.6 will be able to do with (?p{...}).
-
-11. Added support for POSIX character classes like [:alpha:], which Perl is
-adopting.
-
-
-Version 2.08 31-Aug-99
-----------------------
-
-1. When startoffset was not zero and the pattern began with ".*", PCRE was not
-trying to match at the startoffset position, but instead was moving forward to
-the next newline as if a previous match had failed.
-
-2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
-and could get into a loop if a null string was matched other than at the start
-of the subject.
-
-3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
-be distinguished at compile time, and for completeness also added PCRE_DATE.
-
-5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
-in GnuWin32 environments.
-
-
-Version 2.07 29-Jul-99
-----------------------
-
-1. The documentation is now supplied in plain text form and HTML as well as in
-the form of man page sources.
-
-2. C++ compilers don't like assigning (void *) values to other pointer types.
-In particular this affects malloc(). Although there is no problem in Standard
-C, I've put in casts to keep C++ compilers happy.
-
-3. Typo on pcretest.c; a cast of (unsigned char *) in the POSIX regexec() call
-should be (const char *).
-
-4. If NOPOSIX is defined, pcretest.c compiles without POSIX support. This may
-be useful for non-Unix systems who don't want to bother with the POSIX stuff.
-However, I haven't made this a standard facility. The documentation doesn't
-mention it, and the Makefile doesn't support it.
-
-5. The Makefile now contains an "install" target, with editable destinations at
-the top of the file. The pcretest program is not installed.
-
-6. pgrep -V now gives the PCRE version number and date.
-
-7. Fixed bug: a zero repetition after a literal string (e.g. /abcde{0}/) was
-causing the entire string to be ignored, instead of just the last character.
-
-8. If a pattern like /"([^\\"]+|\\.)*"/ is applied in the normal way to a
-non-matching string, it can take a very, very long time, even for strings of
-quite modest length, because of the nested recursion. PCRE now does better in
-some of these cases. It does this by remembering the last required literal
-character in the pattern, and pre-searching the subject to ensure it is present
-before running the real match. In other words, it applies a heuristic to detect
-some types of certain failure quickly, and in the above example, if presented
-with a string that has no trailing " it gives "no match" very quickly.
-
-9. A new runtime option PCRE_NOTEMPTY causes null string matches to be ignored;
-other alternatives are tried instead.
-
-
-Version 2.06 09-Jun-99
-----------------------
-
-1. Change pcretest's output for amount of store used to show just the code
-space, because the remainder (the data block) varies in size between 32-bit and
-64-bit systems.
-
-2. Added an extra argument to pcre_exec() to supply an offset in the subject to
-start matching at. This allows lookbehinds to work when searching for multiple
-occurrences in a string.
-
-3. Added additional options to pcretest for testing multiple occurrences:
-
- /+ outputs the rest of the string that follows a match
- /g loops for multiple occurrences, using the new startoffset argument
- /G loops for multiple occurrences by passing an incremented pointer
-
-4. PCRE wasn't doing the "first character" optimization for patterns starting
-with \b or \B, though it was doing it for other lookbehind assertions. That is,
-it wasn't noticing that a match for a pattern such as /\bxyz/ has to start with
-the letter 'x'. On long subject strings, this gives a significant speed-up.
-
-
-Version 2.05 21-Apr-99
-----------------------
-
-1. Changed the type of magic_number from int to long int so that it works
-properly on 16-bit systems.
-
-2. Fixed a bug which caused patterns starting with .* not to work correctly
-when the subject string contained newline characters. PCRE was assuming
-anchoring for such patterns in all cases, which is not correct because .* will
-not pass a newline unless PCRE_DOTALL is set. It now assumes anchoring only if
-DOTALL is set at top level; otherwise it knows that patterns starting with .*
-must be retried after every newline in the subject.
-
-
-Version 2.04 18-Feb-99
-----------------------
-
-1. For parenthesized subpatterns with repeats whose minimum was zero, the
-computation of the store needed to hold the pattern was incorrect (too large).
-If such patterns were nested a few deep, this could multiply and become a real
-problem.
-
-2. Added /M option to pcretest to show the memory requirement of a specific
-pattern. Made -m a synonym of -s (which does this globally) for compatibility.
-
-3. Subpatterns of the form (regex){n,m} (i.e. limited maximum) were being
-compiled in such a way that the backtracking after subsequent failure was
-pessimal. Something like (a){0,3} was compiled as (a)?(a)?(a)? instead of
-((a)((a)(a)?)?)? with disastrous performance if the maximum was of any size.
-
-
-Version 2.03 02-Feb-99
-----------------------
-
-1. Fixed typo and small mistake in man page.
-
-2. Added 4th condition (GPL supersedes if conflict) and created separate
-LICENCE file containing the conditions.
-
-3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
-Perl, that is the internal \ allows the delimiter to be included in the
-pattern. Locked out the use of \ as a delimiter. If \ immediately follows
-the final delimiter, add \ to the end of the pattern (to test the error).
-
-4. Added the convenience functions for extracting substrings after a successful
-match. Updated pcretest to make it able to test these functions.
-
-
-Version 2.02 14-Jan-99
-----------------------
-
-1. Initialized the working variables associated with each extraction so that
-their saving and restoring doesn't refer to uninitialized store.
-
-2. Put dummy code into study.c in order to trick the optimizer of the IBM C
-compiler for OS/2 into generating correct code. Apparently IBM isn't going to
-fix the problem.
-
-3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
-calls, and wasn't printing the correct value for compiling calls. Increased the
-default value of LOOPREPEAT, and the number of significant figures in the
-times.
-
-4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.
-
-5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
-a building problem on Windows NT with a FAT file system.
-
-
-Version 2.01 21-Oct-98
-----------------------
-
-1. Changed the API for pcre_compile() to allow for the provision of a pointer
-to character tables built by pcre_maketables() in the current locale. If NULL
-is passed, the default tables are used.
-
-
-Version 2.00 24-Sep-98
-----------------------
-
-1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
-it any more.
-
-2. Allow quantification of (?>) groups, and make it work correctly.
-
-3. The first character computation wasn't working for (?>) groups.
-
-4. Correct the implementation of \Z (it is permitted to match on the \n at the
-end of the subject) and add 5.005's \z, which really does match only at the
-very end of the subject.
-
-5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
-
-6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
-DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
-localized options. All options to pcre_study() were also removed.
-
-7. Add other new features from 5.005:
-
- $(?<= positive lookbehind
- $(?<! negative lookbehind
- (?imsx-imsx) added the unsetting capability
- such a setting is global if at outer level; local otherwise
- (?imsx-imsx:) non-capturing groups with option setting
- (?(cond)re|re) conditional pattern matching
-
- A backreference to itself in a repeated group matches the previous
- captured string.
-
-8. General tidying up of studying (both automatic and via "study")
-consequential on the addition of new assertions.
-
-9. As in 5.005, unlimited repeated groups that could match an empty substring
-are no longer faulted at compile time. Instead, the loop is forcibly broken at
-runtime if any iteration does actually match an empty substring.
-
-10. Include the RunTest script in the distribution.
-
-11. Added tests from the Perl 5.005_02 distribution. This showed up a few
-discrepancies, some of which were old and were also with respect to 5.004. They
-have now been fixed.
-
-
-Version 1.09 28-Apr-98
-----------------------
-
-1. A negated single character class followed by a quantifier with a minimum
-value of one (e.g. [^x]{1,6} ) was not compiled correctly. This could lead to
-program crashes, or just wrong answers. This did not apply to negated classes
-containing more than one character, or to minima other than one.
-
-
-Version 1.08 27-Mar-98
-----------------------
-
-1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.
-
-2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
-latter must appear before anything that relies on it in the pattern.
-
-
-Version 1.07 16-Feb-98
-----------------------
-
-1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
-repeat of a potentially empty string).
-
-
-Version 1.06 23-Jan-98
-----------------------
-
-1. Added Markus Oberhumer's little patches for C++.
-
-2. Literal strings longer than 255 characters were broken.
-
-
-Version 1.05 23-Dec-97
-----------------------
-
-1. Negated character classes containing more than one character were failing if
-PCRE_CASELESS was set at run time.
-
-
-Version 1.04 19-Dec-97
-----------------------
-
-1. Corrected the man page, where some "const" qualifiers had been omitted.
-
-2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
-input syntax.
-
-3. Fixed memory leak which occurred when a regex with back references was
-matched with an offsets vector that wasn't big enough. The temporary memory
-that is used in this case wasn't being freed if the match failed.
-
-4. Tidied pcretest to ensure it frees memory that it gets.
-
-5. Temporary memory was being obtained in the case where the passed offsets
-vector was exactly big enough.
-
-6. Corrected definition of offsetof() from change 5 below.
-
-7. I had screwed up change 6 below and broken the rules for the use of
-setjmp(). Now fixed.
-
-
-Version 1.03 18-Dec-97
-----------------------
-
-1. A erroneous regex with a missing opening parenthesis was correctly
-diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
-on some systems.
-
-2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
-it was reported that one broken compiler failed on the former because "code" is
-also an independent variable.
-
-3. The erroneous regex a[]b caused an array overrun reference.
-
-4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
-fail on data ending with that character. (It was going on too far, and checking
-the next character, typically a binary zero.) This was specific to the
-optimized code for single-character negative classes.
-
-5. Added a contributed patch from the TIN world which does the following:
-
- + Add an undef for memmove, in case the the system defines a macro for it.
-
- + Add a definition of offsetof(), in case there isn't one. (I don't know
- the reason behind this - offsetof() is part of the ANSI standard - but
- it does no harm).
-
- + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
- most of the places where whitespace preceded '#'. I have given up and
- allowed the remaining 2 cases to be at the margin.
-
- + Rename some variables in pcre to eliminate shadowing. This seems very
- pedantic, but does no harm, of course.
-
-6. Moved the call to setjmp() into its own function, to get rid of warnings
-from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.
-
-7. Constructs such as \d{8,} were compiling into the equivalent of
-\d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
-outcome, but in this particular case used more store than had been allocated,
-which caused the bug to be discovered because it threw up an internal error.
-
-8. The debugging code in both pcre and pcretest for outputting the compiled
-form of a regex was going wrong in the case of back references followed by
-curly-bracketed repeats.
-
-
-Version 1.02 12-Dec-97
-----------------------
-
-1. Typos in pcre.3 and comments in the source fixed.
-
-2. Applied a contributed patch to get rid of places where it used to remove
-'const' from variables, and fixed some signed/unsigned and uninitialized
-variable warnings.
-
-3. Added the "runtest" target to Makefile.
-
-4. Set default compiler flag to -O2 rather than just -O.
-
-
-Version 1.01 19-Nov-97
-----------------------
-
-1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
-like /([ab]*)*/, that is, for classes with more than one character in them.
-
-2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
-as /((?>a*))*/ (a PCRE_EXTRA facility).
-
-
-Version 1.00 18-Nov-97
-----------------------
-
-1. Added compile-time macros to support systems such as SunOS4 which don't have
-memmove() or strerror() but have other things that can be used instead.
-
-2. Arranged that "make clean" removes the executables.
-
-
-Version 0.99 27-Oct-97
-----------------------
-
-1. Fixed bug in code for optimizing classes with only one character. It was
-initializing a 32-byte map regardless, which could cause it to run off the end
-of the memory it had got.
-
-2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
-
-
-Version 0.98 22-Oct-97
-----------------------
-
-1. Fixed bug in code for handling temporary memory usage when there are more
-back references than supplied space in the ovector. This could cause segfaults.
-
-
-Version 0.97 21-Oct-97
-----------------------
-
-1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
-
-2. Optimized negated single characters not to use a bit map.
-
-3. Brought error texts together as macro definitions; clarified some of them;
-fixed one that was wrong - it said "range out of order" when it meant "invalid
-escape sequence".
-
-4. Changed some char * arguments to const char *.
-
-5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
-
-6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
-pcretest.
-
-
-Version 0.96 16-Oct-97
-----------------------
-
-1. Added a simple "pgrep" utility to the distribution.
-
-2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
-unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
-where "ddd" means "one or more decimal digits".
-
-3. Fixed serious bug. If a pattern had a back reference, but the call to
-pcre_exec() didn't supply a large enough ovector to record the related
-identifying subpattern, the match always failed. PCRE now remembers the number
-of the largest back reference, and gets some temporary memory in which to save
-the offsets during matching if necessary, in order to ensure that
-backreferences always work.
-
-4. Increased the compatibility with Perl in a number of ways:
-
- (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
- to request this handling. The option can be set at compile or exec time.
-
- (b) $ matches before a terminating newline by default; an option
- PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
- mode). The option can be set at compile or exec time.
-
- (c) The handling of \ followed by a digit other than 0 is now supposed to be
- the same as Perl's. If the decimal number it represents is less than 10
- or there aren't that many previous left capturing parentheses, an octal
- escape is read. Inside a character class, it's always an octal escape,
- even if it is a single digit.
-
- (d) An escaped but undefined alphabetic character is taken as a literal,
- unless PCRE_EXTRA is set. Currently this just reserves the remaining
- escapes.
-
- (e) {0} is now permitted. (The previous item is removed from the compiled
- pattern).
-
-5. Changed all the names of code files so that the basic parts are no longer
-than 10 characters, and abolished the teeny "globals.c" file.
-
-6. Changed the handling of character classes; they are now done with a 32-byte
-bit map always.
-
-7. Added the -d and /D options to pcretest to make it possible to look at the
-internals of compilation without having to recompile pcre.
-
-
-Version 0.95 23-Sep-97
-----------------------
-
-1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
-\x20 at the start of a run of normal characters. These were being treated as
-real characters, instead of the source characters being re-checked.
-
-
-Version 0.94 18-Sep-97
-----------------------
-
-1. The functions are now thread-safe, with the caveat that the global variables
-containing pointers to malloc() and free() or alternative functions are the
-same for all threads.
-
-2. Get pcre_study() to generate a bitmap of initial characters for non-
-anchored patterns when this is possible, and use it if passed to pcre_exec().
-
-
-Version 0.93 15-Sep-97
-----------------------
-
-1. /(b)|(:+)/ was computing an incorrect first character.
-
-2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
-but not actually doing anything yet.
-
-3. Treat "-" characters in classes that cannot be part of ranges as literals,
-as Perl does (e.g. [-az] or [az-]).
-
-4. Set the anchored flag if a branch starts with .* or .*? because that tests
-all possible positions.
-
-5. Split up into different modules to avoid including unneeded functions in a
-compiled binary. However, compile and exec are still in one module. The "study"
-function is split off.
-
-6. The character tables are now in a separate module whose source is generated
-by an auxiliary program - but can then be edited by hand if required. There are
-now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
-toupper() in the code.
-
-7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
-make them global. Abolish the function for setting them, as the caller can now
-set them directly.
-
-
-Version 0.92 11-Sep-97
-----------------------
-
-1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
-(e.g. /a{1,3}/) was broken (I mis-optimized it).
-
-2. Caseless matching was not working in character classes if the characters in
-the pattern were in upper case.
-
-3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
-
-4. Make PCRE_ANCHORED public and accept as a compile option.
-
-5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
-PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
-pass them.
-
-6. Give an error if bad option bits passed at compile or run time.
-
-7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
-pcretest to cause it to pass that flag.
-
-8. Add pcre_info(), to get the number of identifying subpatterns, the stored
-options, and the first character, if set.
-
-9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
-
-
-Version 0.91 10-Sep-97
-----------------------
-
-1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
-match the empty string as in /(a*)*/. It was looping and ultimately crashing.
-
-2. PCRE was looping on encountering an indefinitely repeated back reference to
-a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
-Perl does - treats the match as successful.
-
-****