1/* LzFind.h -- Match finder for LZ algorithms
  22017-06-10 : Igor Pavlov : Public domain */
  3
  4#ifndef __LZ_FIND_H
  5#define __LZ_FIND_H
  6
  7#include "7zTypes.h"
  8
  9EXTERN_C_BEGIN
 10
 11typedef UInt32 CLzRef;
 12
 13typedef struct _CMatchFinder
 14{
 15  Byte *buffer;
 16  UInt32 pos;
 17  UInt32 posLimit;
 18  UInt32 streamPos;
 19  UInt32 lenLimit;
 20
 21  UInt32 cyclicBufferPos;
 22  UInt32 cyclicBufferSize; /* it must be = (historySize + 1) */
 23
 24  Byte streamEndWasReached;
 25  Byte btMode;
 26  Byte bigHash;
 27  Byte directInput;
 28
 29  UInt32 matchMaxLen;
 30  CLzRef *hash;
 31  CLzRef *son;
 32  UInt32 hashMask;
 33  UInt32 cutValue;
 34
 35  Byte *bufferBase;
 36  ISeqInStream *stream;
 37  
 38  UInt32 blockSize;
 39  UInt32 keepSizeBefore;
 40  UInt32 keepSizeAfter;
 41
 42  UInt32 numHashBytes;
 43  size_t directInputRem;
 44  UInt32 historySize;
 45  UInt32 fixedHashSize;
 46  UInt32 hashSizeSum;
 47  SRes result;
 48  UInt32 crc[256];
 49  size_t numRefs;
 50
 51  UInt64 expectedDataSize;
 52} CMatchFinder;
 53
 54#define Inline_MatchFinder_GetPointerToCurrentPos(p) ((p)->buffer)
 55
 56#define Inline_MatchFinder_GetNumAvailableBytes(p) ((p)->streamPos - (p)->pos)
 57
 58#define Inline_MatchFinder_IsFinishedOK(p) \
 59    ((p)->streamEndWasReached \
 60        && (p)->streamPos == (p)->pos \
 61        && (!(p)->directInput || (p)->directInputRem == 0))
 62      
 63int MatchFinder_NeedMove(CMatchFinder *p);
 64Byte *MatchFinder_GetPointerToCurrentPos(CMatchFinder *p);
 65void MatchFinder_MoveBlock(CMatchFinder *p);
 66void MatchFinder_ReadIfRequired(CMatchFinder *p);
 67
 68void MatchFinder_Construct(CMatchFinder *p);
 69
 70/* Conditions:
 71     historySize <= 3 GB
 72     keepAddBufferBefore + matchMaxLen + keepAddBufferAfter < 511MB
 73*/
 74int MatchFinder_Create(CMatchFinder *p, UInt32 historySize,
 75    UInt32 keepAddBufferBefore, UInt32 matchMaxLen, UInt32 keepAddBufferAfter,
 76    ISzAllocPtr alloc);
 77void MatchFinder_Free(CMatchFinder *p, ISzAllocPtr alloc);
 78void MatchFinder_Normalize3(UInt32 subValue, CLzRef *items, size_t numItems);
 79void MatchFinder_ReduceOffsets(CMatchFinder *p, UInt32 subValue);
 80
 81UInt32 * GetMatchesSpec1(UInt32 lenLimit, UInt32 curMatch, UInt32 pos, const Byte *buffer, CLzRef *son,
 82    UInt32 _cyclicBufferPos, UInt32 _cyclicBufferSize, UInt32 _cutValue,
 83    UInt32 *distances, UInt32 maxLen);
 84
 85/*
 86Conditions:
 87  Mf_GetNumAvailableBytes_Func must be called before each Mf_GetMatchLen_Func.
 88  Mf_GetPointerToCurrentPos_Func's result must be used only before any other function
 89*/
 90
 91typedef void (*Mf_Init_Func)(void *object);
 92typedef UInt32 (*Mf_GetNumAvailableBytes_Func)(void *object);
 93typedef const Byte * (*Mf_GetPointerToCurrentPos_Func)(void *object);
 94typedef UInt32 (*Mf_GetMatches_Func)(void *object, UInt32 *distances);
 95typedef void (*Mf_Skip_Func)(void *object, UInt32);
 96
 97typedef struct _IMatchFinder
 98{
 99  Mf_Init_Func Init;
100  Mf_GetNumAvailableBytes_Func GetNumAvailableBytes;
101  Mf_GetPointerToCurrentPos_Func GetPointerToCurrentPos;
102  Mf_GetMatches_Func GetMatches;
103  Mf_Skip_Func Skip;
104} IMatchFinder;
105
106void MatchFinder_CreateVTable(CMatchFinder *p, IMatchFinder *vTable);
107
108void MatchFinder_Init_LowHash(CMatchFinder *p);
109void MatchFinder_Init_HighHash(CMatchFinder *p);
110void MatchFinder_Init_3(CMatchFinder *p, int readData);
111void MatchFinder_Init(CMatchFinder *p);
112
113UInt32 Bt3Zip_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances);
114UInt32 Hc3Zip_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances);
115
116void Bt3Zip_MatchFinder_Skip(CMatchFinder *p, UInt32 num);
117void Hc3Zip_MatchFinder_Skip(CMatchFinder *p, UInt32 num);
118
119EXTERN_C_END
120
121#endif