linbpq/LzHash.h

55 lines
2.0 KiB
C

/* LzHash.h -- HASH functions for LZ algorithms
2008-10-04 : Igor Pavlov : Public domain */
#ifndef __LZHASH_H
#define __LZHASH_H
#define kHash2Size (1 << 10)
#define kHash3Size (1 << 16)
#define kHash4Size (1 << 20)
#define kFix3HashSize (kHash2Size)
#define kFix4HashSize (kHash2Size + kHash3Size)
#define kFix5HashSize (kHash2Size + kHash3Size + kHash4Size)
#define HASH2_CALC hashValue = cur[0] | ((LZ_UInt32)cur[1] << 8);
#define HASH3_CALC { \
LZ_UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
hash2Value = temp & (kHash2Size - 1); \
hashValue = (temp ^ ((LZ_UInt32)cur[2] << 8)) & p->hashMask; }
#define HASH4_CALC { \
LZ_UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
hash2Value = temp & (kHash2Size - 1); \
hash3Value = (temp ^ ((LZ_UInt32)cur[2] << 8)) & (kHash3Size - 1); \
hashValue = (temp ^ ((LZ_UInt32)cur[2] << 8) ^ (p->crc[cur[3]] << 5)) & p->hashMask; }
#define HASH5_CALC { \
LZ_UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
hash2Value = temp & (kHash2Size - 1); \
hash3Value = (temp ^ ((LZ_UInt32)cur[2] << 8)) & (kHash3Size - 1); \
hash4Value = (temp ^ ((LZ_UInt32)cur[2] << 8) ^ (p->crc[cur[3]] << 5)); \
hashValue = (hash4Value ^ (p->crc[cur[4]] << 3)) & p->hashMask; \
hash4Value &= (kHash4Size - 1); }
/* #define HASH_ZIP_CALC hashValue = ((cur[0] | ((LZ_UInt32)cur[1] << 8)) ^ p->crc[cur[2]]) & 0xFFFF; */
#define HASH_ZIP_CALC hashValue = ((cur[2] | ((LZ_UInt32)cur[0] << 8)) ^ p->crc[cur[1]]) & 0xFFFF;
#define MT_HASH2_CALC \
hash2Value = (p->crc[cur[0]] ^ cur[1]) & (kHash2Size - 1);
#define MT_HASH3_CALC { \
LZ_UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
hash2Value = temp & (kHash2Size - 1); \
hash3Value = (temp ^ ((LZ_UInt32)cur[2] << 8)) & (kHash3Size - 1); }
#define MT_HASH4_CALC { \
LZ_UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
hash2Value = temp & (kHash2Size - 1); \
hash3Value = (temp ^ ((LZ_UInt32)cur[2] << 8)) & (kHash3Size - 1); \
hash4Value = (temp ^ ((LZ_UInt32)cur[2] << 8) ^ (p->crc[cur[3]] << 5)) & (kHash4Size - 1); }
#endif