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authorNick Clifton <nickc@redhat.com>2017-01-20 10:17:42 +0000
committerNick Clifton <nickc@redhat.com>2017-01-20 10:17:42 +0000
commitde1ab01e8ebf04a3503d8450e6b924c7bb160853 (patch)
treee5c91c036f0d1fcd2f1853908e98cffa1d8fa1f7 /zlib/crc32.c
parent1737c64030af533c520dd1ed1ec2787302cdf830 (diff)
downloadbinutils-gdb-de1ab01e8ebf04a3503d8450e6b924c7bb160853.tar.gz
Sync zlib sources with GCC, upgrading to 1.2.10.
Changes in 1.2.10 (2 Jan 2017) - Avoid warnings on snprintf() return value - Fix bug in deflate_stored() for zero-length input - Fix bug in gzwrite.c that produced corrupt gzip files - Remove files to be installed before copying them in Makefile.in - Add warnings when compiling with assembler code Changes in 1.2.9 (31 Dec 2016) - Fix contrib/minizip to permit unzipping with desktop API [Zouzou] - Improve contrib/blast to return unused bytes - Assure that gzoffset() is correct when appending - Improve compress() and uncompress() to support large lengths - Fix bug in test/example.c where error code not saved - Remedy Coverity warning [Randers-Pehrson] - Improve speed of gzprintf() in transparent mode - Fix inflateInit2() bug when windowBits is 16 or 32 - Change DEBUG macro to ZLIB_DEBUG - Avoid uninitialized access by gzclose_w() - Allow building zlib outside of the source directory - Fix bug that accepted invalid zlib header when windowBits is zero - Fix gzseek() problem on MinGW due to buggy _lseeki64 there - Loop on write() calls in gzwrite.c in case of non-blocking I/O - Add --warn (-w) option to ./configure for more compiler warnings - Reject a window size of 256 bytes if not using the zlib wrapper - Fix bug when level 0 used with Z_HUFFMAN or Z_RLE - Add --debug (-d) option to ./configure to define ZLIB_DEBUG - Fix bugs in creating a very large gzip header - Add uncompress2() function, which returns the input size used - Assure that deflateParams() will not switch functions mid-block - Dramatically speed up deflation for level 0 (storing) - Add gzfread(), duplicating the interface of fread() - Add gzfwrite(), duplicating the interface of fwrite() - Add deflateGetDictionary() function - Use snprintf() for later versions of Microsoft C - Fix *Init macros to use z_ prefix when requested - Replace as400 with os400 for OS/400 support [Monnerat] - Add crc32_z() and adler32_z() functions with size_t lengths - Update Visual Studio project files [AraHaan]
Diffstat (limited to 'zlib/crc32.c')
-rw-r--r--zlib/crc32.c41
1 files changed, 29 insertions, 12 deletions
diff --git a/zlib/crc32.c b/zlib/crc32.c
index e2f5892df91..affcd464ed3 100644
--- a/zlib/crc32.c
+++ b/zlib/crc32.c
@@ -1,5 +1,5 @@
/* crc32.c -- compute the CRC-32 of a data stream
- * Copyright (C) 1995-2006, 2010, 2011, 2012 Mark Adler
+ * Copyright (C) 1995-2006, 2010, 2011, 2012, 2016 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
@@ -30,17 +30,15 @@
#include "zutil.h" /* for STDC and FAR definitions */
-#define local static
-
/* Definitions for doing the crc four data bytes at a time. */
#if !defined(NOBYFOUR) && defined(Z_U4)
# define BYFOUR
#endif
#ifdef BYFOUR
local unsigned long crc32_little OF((unsigned long,
- const unsigned char FAR *, unsigned));
+ const unsigned char FAR *, z_size_t));
local unsigned long crc32_big OF((unsigned long,
- const unsigned char FAR *, unsigned));
+ const unsigned char FAR *, z_size_t));
# define TBLS 8
#else
# define TBLS 1
@@ -201,10 +199,10 @@ const z_crc_t FAR * ZEXPORT get_crc_table()
#define DO8 DO1; DO1; DO1; DO1; DO1; DO1; DO1; DO1
/* ========================================================================= */
-unsigned long ZEXPORT crc32(crc, buf, len)
+unsigned long ZEXPORT crc32_z(crc, buf, len)
unsigned long crc;
const unsigned char FAR *buf;
- uInt len;
+ z_size_t len;
{
if (buf == Z_NULL) return 0UL;
@@ -235,8 +233,29 @@ unsigned long ZEXPORT crc32(crc, buf, len)
return crc ^ 0xffffffffUL;
}
+/* ========================================================================= */
+unsigned long ZEXPORT crc32(crc, buf, len)
+ unsigned long crc;
+ const unsigned char FAR *buf;
+ uInt len;
+{
+ return crc32_z(crc, buf, len);
+}
+
#ifdef BYFOUR
+/*
+ This BYFOUR code accesses the passed unsigned char * buffer with a 32-bit
+ integer pointer type. This violates the strict aliasing rule, where a
+ compiler can assume, for optimization purposes, that two pointers to
+ fundamentally different types won't ever point to the same memory. This can
+ manifest as a problem only if one of the pointers is written to. This code
+ only reads from those pointers. So long as this code remains isolated in
+ this compilation unit, there won't be a problem. For this reason, this code
+ should not be copied and pasted into a compilation unit in which other code
+ writes to the buffer that is passed to these routines.
+ */
+
/* ========================================================================= */
#define DOLIT4 c ^= *buf4++; \
c = crc_table[3][c & 0xff] ^ crc_table[2][(c >> 8) & 0xff] ^ \
@@ -247,7 +266,7 @@ unsigned long ZEXPORT crc32(crc, buf, len)
local unsigned long crc32_little(crc, buf, len)
unsigned long crc;
const unsigned char FAR *buf;
- unsigned len;
+ z_size_t len;
{
register z_crc_t c;
register const z_crc_t FAR *buf4;
@@ -278,7 +297,7 @@ local unsigned long crc32_little(crc, buf, len)
}
/* ========================================================================= */
-#define DOBIG4 c ^= *++buf4; \
+#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
@@ -287,7 +306,7 @@ local unsigned long crc32_little(crc, buf, len)
local unsigned long crc32_big(crc, buf, len)
unsigned long crc;
const unsigned char FAR *buf;
- unsigned len;
+ z_size_t len;
{
register z_crc_t c;
register const z_crc_t FAR *buf4;
@@ -300,7 +319,6 @@ local unsigned long crc32_big(crc, buf, len)
}
buf4 = (const z_crc_t FAR *)(const void FAR *)buf;
- buf4--;
while (len >= 32) {
DOBIG32;
len -= 32;
@@ -309,7 +327,6 @@ local unsigned long crc32_big(crc, buf, len)
DOBIG4;
len -= 4;
}
- buf4++;
buf = (const unsigned char FAR *)buf4;
if (len) do {