1/* LzHash.h -- HASH functions for LZ algorithms
22009-02-07 : Igor Pavlov : Public domain */
3
4#ifndef __LZ_HASH_H
5#define __LZ_HASH_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