xref: /illumos-gate/usr/src/common/lzma/LzFind.h (revision b1efbcd6)
1 /* LzFind.h -- Match finder for LZ algorithms
2 2008-10-04 : Igor Pavlov : Public domain */
3 
4 #ifndef __LZFIND_H
5 #define __LZFIND_H
6 
7 #include "Types.h"
8 
9 typedef UInt32 CLzRef;
10 
11 typedef struct _CMatchFinder
12 {
13   Byte *buffer;
14   UInt32 pos;
15   UInt32 posLimit;
16   UInt32 streamPos;
17   UInt32 lenLimit;
18 
19   UInt32 cyclicBufferPos;
20   UInt32 cyclicBufferSize; /* it must be = (historySize + 1) */
21 
22   UInt32 matchMaxLen;
23   CLzRef *hash;
24   CLzRef *son;
25   UInt32 hashMask;
26   UInt32 cutValue;
27 
28   Byte *bufferBase;
29   ISeqInStream *stream;
30   int streamEndWasReached;
31 
32   UInt32 blockSize;
33   UInt32 keepSizeBefore;
34   UInt32 keepSizeAfter;
35 
36   UInt32 numHashBytes;
37   int directInput;
38   int btMode;
39   /* int skipModeBits; */
40   int bigHash;
41   UInt32 historySize;
42   UInt32 fixedHashSize;
43   UInt32 hashSizeSum;
44   UInt32 numSons;
45   SRes result;
46   UInt32 crc[256];
47 } CMatchFinder;
48 
49 #define Inline_MatchFinder_GetPointerToCurrentPos(p) ((p)->buffer)
50 #define Inline_MatchFinder_GetIndexByte(p, index) ((p)->buffer[(Int32)(index)])
51 
52 #define Inline_MatchFinder_GetNumAvailableBytes(p) ((p)->streamPos - (p)->pos)
53 
54 int MatchFinder_NeedMove(CMatchFinder *p);
55 Byte *MatchFinder_GetPointerToCurrentPos(CMatchFinder *p);
56 void MatchFinder_MoveBlock(CMatchFinder *p);
57 void MatchFinder_ReadIfRequired(CMatchFinder *p);
58 
59 void MatchFinder_Construct(CMatchFinder *p);
60 
61 /* Conditions:
62      historySize <= 3 GB
63      keepAddBufferBefore + matchMaxLen + keepAddBufferAfter < 511MB
64 */
65 int MatchFinder_Create(CMatchFinder *p, UInt32 historySize,
66     UInt32 keepAddBufferBefore, UInt32 matchMaxLen, UInt32 keepAddBufferAfter,
67     ISzAlloc *alloc);
68 void MatchFinder_Free(CMatchFinder *p, ISzAlloc *alloc);
69 void MatchFinder_Normalize3(UInt32 subValue, CLzRef *items, UInt32 numItems);
70 void MatchFinder_ReduceOffsets(CMatchFinder *p, UInt32 subValue);
71 
72 UInt32 * GetMatchesSpec1(UInt32 lenLimit, UInt32 curMatch, UInt32 pos, const Byte *buffer, CLzRef *son,
73     UInt32 _cyclicBufferPos, UInt32 _cyclicBufferSize, UInt32 _cutValue,
74     UInt32 *distances, UInt32 maxLen);
75 
76 /*
77 Conditions:
78   Mf_GetNumAvailableBytes_Func must be called before each Mf_GetMatchLen_Func.
79   Mf_GetPointerToCurrentPos_Func's result must be used only before any other function
80 */
81 
82 typedef void (*Mf_Init_Func)(void *object);
83 typedef Byte (*Mf_GetIndexByte_Func)(void *object, Int32 index);
84 typedef UInt32 (*Mf_GetNumAvailableBytes_Func)(void *object);
85 typedef const Byte * (*Mf_GetPointerToCurrentPos_Func)(void *object);
86 typedef UInt32 (*Mf_GetMatches_Func)(void *object, UInt32 *distances);
87 typedef void (*Mf_Skip_Func)(void *object, UInt32);
88 
89 typedef struct _IMatchFinder
90 {
91   Mf_Init_Func Init;
92   Mf_GetIndexByte_Func GetIndexByte;
93   Mf_GetNumAvailableBytes_Func GetNumAvailableBytes;
94   Mf_GetPointerToCurrentPos_Func GetPointerToCurrentPos;
95   Mf_GetMatches_Func GetMatches;
96   Mf_Skip_Func Skip;
97 } IMatchFinder;
98 
99 void MatchFinder_CreateVTable(CMatchFinder *p, IMatchFinder *vTable);
100 
101 void MatchFinder_Init(CMatchFinder *p);
102 UInt32 Bt3Zip_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances);
103 UInt32 Hc3Zip_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances);
104 void Bt3Zip_MatchFinder_Skip(CMatchFinder *p, UInt32 num);
105 void Hc3Zip_MatchFinder_Skip(CMatchFinder *p, UInt32 num);
106 
107 #endif
108