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zlib 1.2.0.2

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This commit is contained in:
Mark Adler
2011-09-09 23:22:10 -07:00
parent 13a294f044
commit 8e34b3a802
58 changed files with 7303 additions and 5374 deletions
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28
crc32.c
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@@ -18,25 +18,29 @@
# endif /* !DYNAMIC_CRC_TABLE */
#endif /* MAKECRCH */
#include "zlib.h"
#include "zutil.h"
#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 */
# ifdef STDC /* need ANSI C limits.h to determine sizes */
# include <limits.h>
# define BYFOUR
# if (UINT_MAX == 4294967295)
# if (UINT_MAX == 0xffffffffUL)
typedef unsigned int u4;
# elif (ULONG_MAX == 4294967295)
typedef unsigned long u4;
# elif (USHRT_MAX == 4294967295)
typedef unsigned short u4;
# else
# undef BYFOUR /* can't find a four-byte integer type! */
# 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 /* STDC */
#endif /* !NOBYFOUR */
/* Definitions for doing the crc four data bytes at a time. */
@@ -95,7 +99,7 @@ local void make_crc_table()
/* terms of polynomial defining this crc (except x^32): */
static const unsigned char p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26};
/* make exclusive-or pattern from polynomial (0xedb88320L) */
/* make exclusive-or pattern from polynomial (0xedb88320UL) */
poly = 0UL;
for (n = 0; n < sizeof(p)/sizeof(unsigned char); n++)
poly |= 1UL << (31 - p[n]);
@@ -240,7 +244,7 @@ local unsigned long crc32_little(crc, buf, len)
c = (u4)crc;
c = ~c;
while (len && ((int)buf & 3)) {
while (len && ((size_t)buf & 3)) {
c = crc_table[0][(c ^ *buf++) & 0xff] ^ (c >> 8);
len--;
}
@@ -280,7 +284,7 @@ local unsigned long crc32_big(crc, buf, len)
c = REV((u4)crc);
c = ~c;
while (len && ((int)buf & 3)) {
while (len && ((size_t)buf & 3)) {
c = crc_table[4][(c >> 24) ^ *buf++] ^ (c << 8);
len--;
}