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 87 /* ---------- Internal Functions ---------- */ 88 89 extern const Byte PPMD8_kExpEscape[16]; 90 91 #ifdef PPMD_32BIT 92 #define Ppmd8_GetPtr(p, ptr) (ptr) 93 #define Ppmd8_GetContext(p, ptr) (ptr) 94 #define Ppmd8_GetStats(p, ctx) ((ctx)->Stats) 95 #else 96 #define Ppmd8_GetPtr(p, offs) ((void *)((p)->Base + (offs))) 97 #define Ppmd8_GetContext(p, offs) ((CPpmd8_Context *)Ppmd8_GetPtr((p), (offs))) 98 #define Ppmd8_GetStats(p, ctx) ((CPpmd_State *)Ppmd8_GetPtr((p), ((ctx)->Stats))) 99 #endif 100 101 #define Ppmd8_GetBinSumm(p) \ 102 &p->BinSumm[p->NS2Indx[Ppmd8Context_OneState(p->MinContext)->Freq - 1]][ \ 103 p->NS2BSIndx[Ppmd8_GetContext(p, p->MinContext->Suffix)->NumStats] + \ 104 p->PrevSuccess + p->MinContext->Flags + ((p->RunLength >> 26) & 0x20)] 105 106 107 typedef struct 108 { 109 /* Base Functions */ 110 void (*Ppmd8_Construct)(CPpmd8 *p); 111 Bool (*Ppmd8_Alloc)(CPpmd8 *p, UInt32 size); 112 void (*Ppmd8_Free)(CPpmd8 *p); 113 void (*Ppmd8_Init)(CPpmd8 *p, unsigned max_order, unsigned restore_method); 114 #define Ppmd7_WasAllocated(p) ((p)->Base != NULL) 115 116 /* Decode Functions */ 117 int (*Ppmd8_RangeDec_Init)(CPpmd8 *p); 118 int (*Ppmd8_DecodeSymbol)(CPpmd8 *p); 119 } IPpmd8; 120 121 extern const IPpmd8 __archive_ppmd8_functions; 122 123 #endif 124