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-rwxr-xr-xC/LzHash.h54
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diff --git a/C/LzHash.h b/C/LzHash.h
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+/* LzHash.h -- HASH functions for LZ algorithms
+2009-02-07 : Igor Pavlov : Public domain */
+
+#ifndef __LZ_HASH_H
+#define __LZ_HASH_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] | ((UInt32)cur[1] << 8);
+
+#define HASH3_CALC { \
+ UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
+ hash2Value = temp & (kHash2Size - 1); \
+ hashValue = (temp ^ ((UInt32)cur[2] << 8)) & p->hashMask; }
+
+#define HASH4_CALC { \
+ UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
+ hash2Value = temp & (kHash2Size - 1); \
+ hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); \
+ hashValue = (temp ^ ((UInt32)cur[2] << 8) ^ (p->crc[cur[3]] << 5)) & p->hashMask; }
+
+#define HASH5_CALC { \
+ UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
+ hash2Value = temp & (kHash2Size - 1); \
+ hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); \
+ hash4Value = (temp ^ ((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] | ((UInt32)cur[1] << 8)) ^ p->crc[cur[2]]) & 0xFFFF; */
+#define HASH_ZIP_CALC hashValue = ((cur[2] | ((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 { \
+ UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
+ hash2Value = temp & (kHash2Size - 1); \
+ hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); }
+
+#define MT_HASH4_CALC { \
+ UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
+ hash2Value = temp & (kHash2Size - 1); \
+ hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); \
+ hash4Value = (temp ^ ((UInt32)cur[2] << 8) ^ (p->crc[cur[3]] << 5)) & (kHash4Size - 1); }
+
+#endif