contrib/libarchive/libarchive/archive_ppmd8_private.h

   1 /* Ppmd8.h -- PPMdI codec
   2 2011-01-27 : Igor Pavlov : Public domain
   3 This code is based on:
   4   PPMd var.I (2002): Dmitry Shkarin : Public domain
   5   Carryless rangecoder (1999): Dmitry Subbotin : Public domain */
   6
   7 #ifndef ARCHIVE_PPMD8_PRIVATE_H_INCLUDED
   8 #define ARCHIVE_PPMD8_PRIVATE_H_INCLUDED
   9
  10 #include "archive_ppmd_private.h"
  11
  12 #define PPMD8_MIN_ORDER 2
  13 #define PPMD8_MAX_ORDER 16
  14
  15 struct CPpmd8_Context_;
  16
  17 typedef
  18   #ifdef PPMD_32BIT
  19     struct CPpmd8_Context_ *
  20   #else
  21     UInt32
  22   #endif
  23   CPpmd8_Context_Ref;
  24
  25 #pragma pack(push, 1)
  26
  27 typedef struct CPpmd8_Context_
  28 {
  29   Byte NumStats;
  30   Byte Flags;
  31   UInt16 SummFreq;
  32   CPpmd_State_Ref Stats;
  33   CPpmd8_Context_Ref Suffix;
  34 } CPpmd8_Context;
  35
  36 #pragma pack(pop)
  37
  38 #define Ppmd8Context_OneState(p) ((CPpmd_State *)&(p)->SummFreq)
  39
  40 /* The BUG in Shkarin's code for FREEZE mode was fixed, but that fixed
  41    code is not compatible with original code for some files compressed
  42    in FREEZE mode. So we disable FREEZE mode support. */
  43
  44 enum
  45 {
  46   PPMD8_RESTORE_METHOD_RESTART,
  47   PPMD8_RESTORE_METHOD_CUT_OFF
  48   #ifdef PPMD8_FREEZE_SUPPORT
  49   , PPMD8_RESTORE_METHOD_FREEZE
  50   #endif
  51 };
  52
  53 typedef struct
  54 {
  55   CPpmd8_Context *MinContext, *MaxContext;
  56   CPpmd_State *FoundState;
  57   unsigned OrderFall, InitEsc, PrevSuccess, MaxOrder;
  58   Int32 RunLength, InitRL; /* must be 32-bit at least */
  59
  60   UInt32 Size;
  61   UInt32 GlueCount;
  62   Byte *Base, *LoUnit, *HiUnit, *Text, *UnitsStart;
  63   UInt32 AlignOffset;
  64   unsigned RestoreMethod;
  65
  66   /* Range Coder */
  67   UInt32 Range;
  68   UInt32 Code;
  69   UInt32 Low;
  70   union
  71   {
  72     IByteIn *In;
  73     IByteOut *Out;
  74   } Stream;
  75
  76   Byte Indx2Units[PPMD_NUM_INDEXES];
  77   Byte Units2Indx[128];
  78   CPpmd_Void_Ref FreeList[PPMD_NUM_INDEXES];
  79   UInt32 Stamps[PPMD_NUM_INDEXES];
  80
  81   Byte NS2BSIndx[256], NS2Indx[260];
  82   CPpmd_See DummySee, See[24][32];
  83   UInt16 BinSumm[25][64];
  84 } CPpmd8;
  85
  86 void Ppmd8_Construct(CPpmd8 *p);
  87 Bool Ppmd8_Alloc(CPpmd8 *p, UInt32 size);
  88 void Ppmd8_Free(CPpmd8 *p);
  89 void Ppmd8_Init(CPpmd8 *p, unsigned maxOrder, unsigned restoreMethod);
  90 #define Ppmd8_WasAllocated(p) ((p)->Base != NULL)
  91
  92
  93 /* ---------- Internal Functions ---------- */
  94
  95 extern const Byte PPMD8_kExpEscape[16];
  96
  97 #ifdef PPMD_32BIT
  98   #define Ppmd8_GetPtr(p, ptr) (ptr)
  99   #define Ppmd8_GetContext(p, ptr) (ptr)
 100   #define Ppmd8_GetStats(p, ctx) ((ctx)->Stats)
 101 #else
 102   #define Ppmd8_GetPtr(p, offs) ((void *)((p)->Base + (offs)))
 103   #define Ppmd8_GetContext(p, offs) ((CPpmd8_Context *)Ppmd8_GetPtr((p), (offs)))
 104   #define Ppmd8_GetStats(p, ctx) ((CPpmd_State *)Ppmd8_GetPtr((p), ((ctx)->Stats)))
 105 #endif
 106
 107 void Ppmd8_Update1(CPpmd8 *p);
 108 void Ppmd8_Update1_0(CPpmd8 *p);
 109 void Ppmd8_Update2(CPpmd8 *p);
 110 void Ppmd8_UpdateBin(CPpmd8 *p);
 111
 112 #define Ppmd8_GetBinSumm(p) \
 113     &p->BinSumm[p->NS2Indx[Ppmd8Context_OneState(p->MinContext)->Freq - 1]][ \
 114     p->NS2BSIndx[Ppmd8_GetContext(p, p->MinContext->Suffix)->NumStats] + \
 115     p->PrevSuccess + p->MinContext->Flags + ((p->RunLength >> 26) & 0x20)]
 116
 117 CPpmd_See *Ppmd8_MakeEscFreq(CPpmd8 *p, unsigned numMasked, UInt32 *scale);
 118
 119
 120 /* ---------- Decode ---------- */
 121
 122 Bool Ppmd8_RangeDec_Init(CPpmd8 *p);
 123 #define Ppmd8_RangeDec_IsFinishedOK(p) ((p)->Code == 0)
 124 int Ppmd8_DecodeSymbol(CPpmd8 *p); /* returns: -1 as EndMarker, -2 as DataError */
 125
 126 /* ---------- Encode ---------- */
 127
 128 #define Ppmd8_RangeEnc_Init(p) { (p)->Low = 0; (p)->Range = 0xFFFFFFFF; }
 129 void Ppmd8_RangeEnc_FlushData(CPpmd8 *p);
 130 void Ppmd8_EncodeSymbol(CPpmd8 *p, int symbol); /* symbol = -1 means EndMarker */
 131
 132 typedef struct
 133 {
 134   /* Base Functions */
 135   void (*Ppmd8_Construct)(CPpmd8 *p);
 136   Bool (*Ppmd8_Alloc)(CPpmd8 *p, UInt32 size);
 137   void (*Ppmd8_Free)(CPpmd8 *p);
 138   void (*Ppmd8_Init)(CPpmd8 *p, unsigned max_order, unsigned restore_method);
 139   #define Ppmd7_WasAllocated(p) ((p)->Base != NULL)
 140
 141   /* Decode Functions */
 142   int (*Ppmd8_RangeDec_Init)(CPpmd8 *p);
 143   int (*Ppmd8_DecodeSymbol)(CPpmd8 *p);
 144 } IPpmd8;
 145
 146 extern const IPpmd8 __archive_ppmd8_functions;
 147
 148 #endif