1// LZMA.h
2
3#ifndef __LZMA_H
4#define __LZMA_H
5
6namespace NCompress {
7namespace NLZMA {
8
9const UInt32 kNumRepDistances = 4;
10
11const int kNumStates = 12;
12
13const Byte kLiteralNextStates[kNumStates] = {0, 0, 0, 0, 1, 2, 3, 4,  5,  6,   4, 5};
14const Byte kMatchNextStates[kNumStates]   = {7, 7, 7, 7, 7, 7, 7, 10, 10, 10, 10, 10};
15const Byte kRepNextStates[kNumStates]     = {8, 8, 8, 8, 8, 8, 8, 11, 11, 11, 11, 11};
16const Byte kShortRepNextStates[kNumStates]= {9, 9, 9, 9, 9, 9, 9, 11, 11, 11, 11, 11};
17
18class CState
19{
20public:
21  Byte Index;
22  void Init() { Index = 0; }
23  void UpdateChar() { Index = kLiteralNextStates[Index]; }
24  void UpdateMatch() { Index = kMatchNextStates[Index]; }
25  void UpdateRep() { Index = kRepNextStates[Index]; }
26  void UpdateShortRep() { Index = kShortRepNextStates[Index]; }
27  bool IsCharState() const { return Index < 7; }
28};
29
30const int kNumPosSlotBits = 6;
31const int kDicLogSizeMin = 0;
32const int kDicLogSizeMax = 32;
33const int kDistTableSizeMax = kDicLogSizeMax * 2;
34
35const UInt32 kNumLenToPosStates = 4;
36
37inline UInt32 GetLenToPosState(UInt32 len)
38{
39  len -= 2;
40  if (len < kNumLenToPosStates)
41    return len;
42  return kNumLenToPosStates - 1;
43}
44
45namespace NLength {
46
47const int kNumPosStatesBitsMax = 4;
48const UInt32 kNumPosStatesMax = (1 << kNumPosStatesBitsMax);
49
50const int kNumPosStatesBitsEncodingMax = 4;
51const UInt32 kNumPosStatesEncodingMax = (1 << kNumPosStatesBitsEncodingMax);
52
53const int kNumLowBits = 3;
54const int kNumMidBits = 3;
55const int kNumHighBits = 8;
56const UInt32 kNumLowSymbols = 1 << kNumLowBits;
57const UInt32 kNumMidSymbols = 1 << kNumMidBits;
58const UInt32 kNumSymbolsTotal = kNumLowSymbols + kNumMidSymbols + (1 << kNumHighBits);
59
60}
61
62const UInt32 kMatchMinLen = 2;
63const UInt32 kMatchMaxLen = kMatchMinLen + NLength::kNumSymbolsTotal - 1;
64
65const int kNumAlignBits = 4;
66const UInt32 kAlignTableSize = 1 << kNumAlignBits;
67const UInt32 kAlignMask = (kAlignTableSize - 1);
68
69const UInt32 kStartPosModelIndex = 4;
70const UInt32 kEndPosModelIndex = 14;
71const UInt32 kNumPosModels = kEndPosModelIndex - kStartPosModelIndex;
72
73const UInt32 kNumFullDistances = 1 << (kEndPosModelIndex / 2);
74
75const int kNumLitPosStatesBitsEncodingMax = 4;
76const int kNumLitContextBitsMax = 8;
77
78const int kNumMoveBits = 5;
79
80}}
81
82#endif
83