1 /* Ppmd.h -- PPMD codec common code 2 2010-03-12 : Igor Pavlov : Public domain 3 This code is based on PPMd var.H (2001): Dmitry Shkarin : Public domain */ 4 5 #ifndef __LIBARCHIVE_BUILD 6 #error This header is only to be used internally to libarchive. 7 #endif 8 9 #ifndef ARCHIVE_PPMD_PRIVATE_H_INCLUDED 10 #define ARCHIVE_PPMD_PRIVATE_H_INCLUDED 11 12 #include <stddef.h> 13 14 #include "archive_read_private.h" 15 16 /*** Begin defined in Types.h ***/ 17 18 #if !defined(ZCONF_H) 19 typedef unsigned char Byte; 20 #endif 21 typedef short Int16; 22 typedef unsigned short UInt16; 23 24 #ifdef _LZMA_UINT32_IS_ULONG 25 typedef long Int32; 26 typedef unsigned long UInt32; 27 #else 28 typedef int Int32; 29 typedef unsigned int UInt32; 30 #endif 31 32 #ifdef _SZ_NO_INT_64 33 34 /* define _SZ_NO_INT_64, if your compiler doesn't support 64-bit integers. 35 NOTES: Some code will work incorrectly in that case! */ 36 37 typedef long Int64; 38 typedef unsigned long UInt64; 39 40 #else 41 42 #if defined(_MSC_VER) || defined(__BORLANDC__) 43 typedef __int64 Int64; 44 typedef unsigned __int64 UInt64; 45 #define UINT64_CONST(n) n 46 #else 47 typedef long long int Int64; 48 typedef unsigned long long int UInt64; 49 #define UINT64_CONST(n) n ## ULL 50 #endif 51 52 #endif 53 54 typedef int Bool; 55 #define True 1 56 #define False 0 57 58 /* The following interfaces use first parameter as pointer to structure */ 59 60 typedef struct 61 { 62 struct archive_read *a; 63 Byte (*Read)(void *p); /* reads one byte, returns 0 in case of EOF or error */ 64 } IByteIn; 65 66 typedef struct 67 { 68 struct archive_write *a; 69 void (*Write)(void *p, Byte b); 70 } IByteOut; 71 72 73 typedef struct 74 { 75 void *(*Alloc)(void *p, size_t size); 76 void (*Free)(void *p, void *address); /* address can be 0 */ 77 } ISzAlloc; 78 79 /*** End defined in Types.h ***/ 80 /*** Begin defined in CpuArch.h ***/ 81 82 #if defined(_M_IX86) || defined(__i386__) 83 #define MY_CPU_X86 84 #endif 85 86 #if defined(MY_CPU_X86) || defined(_M_ARM) 87 #define MY_CPU_32BIT 88 #endif 89 90 #ifdef MY_CPU_32BIT 91 #define PPMD_32BIT 92 #endif 93 94 /*** End defined in CpuArch.h ***/ 95 96 #define PPMD_INT_BITS 7 97 #define PPMD_PERIOD_BITS 7 98 #define PPMD_BIN_SCALE (1 << (PPMD_INT_BITS + PPMD_PERIOD_BITS)) 99 100 #define PPMD_GET_MEAN_SPEC(summ, shift, round) (((summ) + (1 << ((shift) - (round)))) >> (shift)) 101 #define PPMD_GET_MEAN(summ) PPMD_GET_MEAN_SPEC((summ), PPMD_PERIOD_BITS, 2) 102 #define PPMD_UPDATE_PROB_0(prob) ((prob) + (1 << PPMD_INT_BITS) - PPMD_GET_MEAN(prob)) 103 #define PPMD_UPDATE_PROB_1(prob) ((prob) - PPMD_GET_MEAN(prob)) 104 105 #define PPMD_N1 4 106 #define PPMD_N2 4 107 #define PPMD_N3 4 108 #define PPMD_N4 ((128 + 3 - 1 * PPMD_N1 - 2 * PPMD_N2 - 3 * PPMD_N3) / 4) 109 #define PPMD_NUM_INDEXES (PPMD_N1 + PPMD_N2 + PPMD_N3 + PPMD_N4) 110 111 /* SEE-contexts for PPM-contexts with masked symbols */ 112 typedef struct 113 { 114 UInt16 Summ; /* Freq */ 115 Byte Shift; /* Speed of Freq change; low Shift is for fast change */ 116 Byte Count; /* Count to next change of Shift */ 117 } CPpmd_See; 118 119 #define Ppmd_See_Update(p) if ((p)->Shift < PPMD_PERIOD_BITS && --(p)->Count == 0) \ 120 { (p)->Summ <<= 1; (p)->Count = (Byte)(3 << (p)->Shift++); } 121 122 typedef struct 123 { 124 Byte Symbol; 125 Byte Freq; 126 UInt16 SuccessorLow; 127 UInt16 SuccessorHigh; 128 } CPpmd_State; 129 130 typedef 131 #ifdef PPMD_32BIT 132 CPpmd_State * 133 #else 134 UInt32 135 #endif 136 CPpmd_State_Ref; 137 138 typedef 139 #ifdef PPMD_32BIT 140 void * 141 #else 142 UInt32 143 #endif 144 CPpmd_Void_Ref; 145 146 typedef 147 #ifdef PPMD_32BIT 148 Byte * 149 #else 150 UInt32 151 #endif 152 CPpmd_Byte_Ref; 153 154 #define PPMD_SetAllBitsIn256Bytes(p) \ 155 { unsigned j; for (j = 0; j < 256 / sizeof(p[0]); j += 8) { \ 156 p[j+7] = p[j+6] = p[j+5] = p[j+4] = p[j+3] = p[j+2] = p[j+1] = p[j+0] = ~(size_t)0; }} 157 158 #endif 159