1 /* LzHash.h -- HASH functions for LZ algorithms 2 2008-10-04 : Igor Pavlov : Public domain */ 3 4 #ifndef __LZHASH_H 5 #define __LZHASH_H 6 7 #define kHash2Size (1 << 10) 8 #define kHash3Size (1 << 16) 9 #define kHash4Size (1 << 20) 10 11 #define kFix3HashSize (kHash2Size) 12 #define kFix4HashSize (kHash2Size + kHash3Size) 13 #define kFix5HashSize (kHash2Size + kHash3Size + kHash4Size) 14 15 #define HASH2_CALC hashValue = cur[0] | ((UInt32)cur[1] << 8); 16 17 #define HASH3_CALC { \ 18 UInt32 temp = p->crc[cur[0]] ^ cur[1]; \ 19 hash2Value = temp & (kHash2Size - 1); \ 20 hashValue = (temp ^ ((UInt32)cur[2] << 8)) & p->hashMask; } 21 22 #define HASH4_CALC { \ 23 UInt32 temp = p->crc[cur[0]] ^ cur[1]; \ 24 hash2Value = temp & (kHash2Size - 1); \ 25 hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); \ 26 hashValue = (temp ^ ((UInt32)cur[2] << 8) ^ (p->crc[cur[3]] << 5)) & p->hashMask; } 27 28 #define HASH5_CALC { \ 29 UInt32 temp = p->crc[cur[0]] ^ cur[1]; \ 30 hash2Value = temp & (kHash2Size - 1); \ 31 hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); \ 32 hash4Value = (temp ^ ((UInt32)cur[2] << 8) ^ (p->crc[cur[3]] << 5)); \ 33 hashValue = (hash4Value ^ (p->crc[cur[4]] << 3)) & p->hashMask; \ 34 hash4Value &= (kHash4Size - 1); } 35 36 /* #define HASH_ZIP_CALC hashValue = ((cur[0] | ((UInt32)cur[1] << 8)) ^ p->crc[cur[2]]) & 0xFFFF; */ 37 #define HASH_ZIP_CALC hashValue = ((cur[2] | ((UInt32)cur[0] << 8)) ^ p->crc[cur[1]]) & 0xFFFF; 38 39 40 #define MT_HASH2_CALC \ 41 hash2Value = (p->crc[cur[0]] ^ cur[1]) & (kHash2Size - 1); 42 43 #define MT_HASH3_CALC { \ 44 UInt32 temp = p->crc[cur[0]] ^ cur[1]; \ 45 hash2Value = temp & (kHash2Size - 1); \ 46 hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); } 47 48 #define MT_HASH4_CALC { \ 49 UInt32 temp = p->crc[cur[0]] ^ cur[1]; \ 50 hash2Value = temp & (kHash2Size - 1); \ 51 hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); \ 52 hash4Value = (temp ^ ((UInt32)cur[2] << 8) ^ (p->crc[cur[3]] << 5)) & (kHash4Size - 1); } 53 54 #endif 55