1/* LzFind.h -- Match finder for LZ algorithms
  22015-10-15 : 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} CMatchFinder;
 51
 52#define Inline_MatchFinder_GetPointerToCurrentPos(p) ((p)->buffer)
 53
 54#define Inline_MatchFinder_GetNumAvailableBytes(p) ((p)->streamPos - (p)->pos)
 55
 56#define Inline_MatchFinder_IsFinishedOK(p) \
 57    ((p)->streamEndWasReached \
 58        && (p)->streamPos == (p)->pos \
 59        && (!(p)->directInput || (p)->directInputRem == 0))
 60      
 61int MatchFinder_NeedMove(CMatchFinder *p);
 62Byte *MatchFinder_GetPointerToCurrentPos(CMatchFinder *p);
 63void MatchFinder_MoveBlock(CMatchFinder *p);
 64void MatchFinder_ReadIfRequired(CMatchFinder *p);
 65
 66void MatchFinder_Construct(CMatchFinder *p);
 67
 68/* Conditions:
 69     historySize <= 3 GB
 70     keepAddBufferBefore + matchMaxLen + keepAddBufferAfter < 511MB
 71*/
 72int MatchFinder_Create(CMatchFinder *p, UInt32 historySize,
 73    UInt32 keepAddBufferBefore, UInt32 matchMaxLen, UInt32 keepAddBufferAfter,
 74    ISzAlloc *alloc);
 75void MatchFinder_Free(CMatchFinder *p, ISzAlloc *alloc);
 76void MatchFinder_Normalize3(UInt32 subValue, CLzRef *items, size_t numItems);
 77void MatchFinder_ReduceOffsets(CMatchFinder *p, UInt32 subValue);
 78
 79UInt32 * GetMatchesSpec1(UInt32 lenLimit, UInt32 curMatch, UInt32 pos, const Byte *buffer, CLzRef *son,
 80    UInt32 _cyclicBufferPos, UInt32 _cyclicBufferSize, UInt32 _cutValue,
 81    UInt32 *distances, UInt32 maxLen);
 82
 83/*
 84Conditions:
 85  Mf_GetNumAvailableBytes_Func must be called before each Mf_GetMatchLen_Func.
 86  Mf_GetPointerToCurrentPos_Func's result must be used only before any other function
 87*/
 88
 89typedef void (*Mf_Init_Func)(void *object);
 90typedef UInt32 (*Mf_GetNumAvailableBytes_Func)(void *object);
 91typedef const Byte * (*Mf_GetPointerToCurrentPos_Func)(void *object);
 92typedef UInt32 (*Mf_GetMatches_Func)(void *object, UInt32 *distances);
 93typedef void (*Mf_Skip_Func)(void *object, UInt32);
 94
 95typedef struct _IMatchFinder
 96{
 97  Mf_Init_Func Init;
 98  Mf_GetNumAvailableBytes_Func GetNumAvailableBytes;
 99  Mf_GetPointerToCurrentPos_Func GetPointerToCurrentPos;
100  Mf_GetMatches_Func GetMatches;
101  Mf_Skip_Func Skip;
102} IMatchFinder;
103
104void MatchFinder_CreateVTable(CMatchFinder *p, IMatchFinder *vTable);
105
106void MatchFinder_Init_2(CMatchFinder *p, int readData);
107void MatchFinder_Init(CMatchFinder *p);
108
109UInt32 Bt3Zip_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances);
110UInt32 Hc3Zip_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances);
111
112void Bt3Zip_MatchFinder_Skip(CMatchFinder *p, UInt32 num);
113void Hc3Zip_MatchFinder_Skip(CMatchFinder *p, UInt32 num);
114
115EXTERN_C_END
116
117#endif