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9.09 beta

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This commit is contained in:
Igor Pavlov
2009-12-14 00:00:00 +00:00
committed by Kornel Lesiński
parent 2fed872194
commit 1fbaf0aac5
179 changed files with 3365 additions and 2136 deletions
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77
C/7zCrc.c
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@@ -1,35 +1,74 @@
/* 7zCrc.c -- CRC32 calculation
2008-08-05
Igor Pavlov
Public domain */
2009-11-23 : Igor Pavlov : Public domain */
#include "7zCrc.h"
#include "CpuArch.h"
#define kCrcPoly 0xEDB88320
UInt32 g_CrcTable[256];
void MY_FAST_CALL CrcGenerateTable(void)
#ifdef MY_CPU_LE
#define CRC_NUM_TABLES 8
#else
#define CRC_NUM_TABLES 1
#endif
typedef UInt32 (MY_FAST_CALL *CRC_FUNC)(UInt32 v, const void *data, size_t size, const UInt32 *table);
static CRC_FUNC g_CrcUpdate;
UInt32 g_CrcTable[256 * CRC_NUM_TABLES];
#if CRC_NUM_TABLES == 1
#define CRC_UPDATE_BYTE_2(crc, b) (table[((crc) ^ (b)) & 0xFF] ^ ((crc) >> 8))
static UInt32 MY_FAST_CALL CrcUpdateT1(UInt32 v, const void *data, size_t size, const UInt32 *table)
{
const Byte *p = (const Byte *)data;
for (; size > 0; size--, p++)
v = CRC_UPDATE_BYTE_2(v, *p);
return v;
}
#else
UInt32 MY_FAST_CALL CrcUpdateT4(UInt32 v, const void *data, size_t size, const UInt32 *table);
UInt32 MY_FAST_CALL CrcUpdateT8(UInt32 v, const void *data, size_t size, const UInt32 *table);
#endif
UInt32 MY_FAST_CALL CrcUpdate(UInt32 v, const void *data, size_t size)
{
return g_CrcUpdate(v, data, size, g_CrcTable);
}
UInt32 MY_FAST_CALL CrcCalc(const void *data, size_t size)
{
return g_CrcUpdate(CRC_INIT_VAL, data, size, g_CrcTable) ^ CRC_INIT_VAL;
}
void MY_FAST_CALL CrcGenerateTable()
{
UInt32 i;
for (i = 0; i < 256; i++)
{
UInt32 r = i;
int j;
unsigned j;
for (j = 0; j < 8; j++)
r = (r >> 1) ^ (kCrcPoly & ~((r & 1) - 1));
g_CrcTable[i] = r;
}
}
UInt32 MY_FAST_CALL CrcUpdate(UInt32 v, const void *data, size_t size)
{
const Byte *p = (const Byte *)data;
for (; size > 0 ; size--, p++)
v = CRC_UPDATE_BYTE(v, *p);
return v;
}
UInt32 MY_FAST_CALL CrcCalc(const void *data, size_t size)
{
return CrcUpdate(CRC_INIT_VAL, data, size) ^ 0xFFFFFFFF;
#if CRC_NUM_TABLES == 1
g_CrcUpdate = CrcUpdateT1;
#else
for (; i < 256 * CRC_NUM_TABLES; i++)
{
UInt32 r = g_CrcTable[i - 256];
g_CrcTable[i] = g_CrcTable[r & 0xFF] ^ (r >> 8);
}
g_CrcUpdate = CrcUpdateT4;
#ifdef MY_CPU_X86_OR_AMD64
if (!CPU_Is_InOrder())
g_CrcUpdate = CrcUpdateT8;
#endif
#endif
}