physfs/lzma/C/7zCrc.c

33 lines
626 B
C

/* 7zCrc.c */
#include "7zCrc.h"
#define kCrcPoly 0xEDB88320
UInt32 g_CrcTable[256];
void MY_FAST_CALL CrcGenerateTable(void)
{
UInt32 i;
for (i = 0; i < 256; i++)
{
UInt32 r = i;
int 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;
}