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zlib 0.9

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This commit is contained in:
Mark Adler
2011-09-09 23:06:52 -07:00
parent 4ca984fb44
commit 64b2e89203
23 changed files with 783 additions and 200 deletions
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16
crc32.c
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@@ -3,12 +3,17 @@
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* $Id: crc32.c,v 1.4 1995/04/14 14:55:12 jloup Exp $ */
/* $Id: crc32.c,v 1.5 1995/05/01 13:55:46 jloup Exp $ */
#include "zlib.h"
extern uLong crc_table[]; /* crc table, defined below */
#define DO1(buf) crc = crc_table[((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8);
#define DO2(buf) DO1(buf); DO1(buf);
#define DO4(buf) DO2(buf); DO2(buf);
#define DO8(buf) DO4(buf); DO4(buf);
/* ========================================================================= */
uLong crc32(crc, buf, len)
uLong crc;
@@ -17,8 +22,13 @@ uLong crc32(crc, buf, len)
{
if (buf == Z_NULL) return 0L;
crc = crc ^ 0xffffffffL;
while (len >= 8)
{
DO8(buf);
len -= 8;
}
if (len) do {
crc = crc_table[((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8);
DO1(buf);
} while (--len);
return crc ^ 0xffffffffL;
}
@@ -29,7 +39,7 @@ uLong crc32(crc, buf, len)
*/
#ifdef DYNAMIC_CRC_TABLE
void make_crc_table()
local void make_crc_table()
{
uLong c;
int n, k;