1 /* LzmaDec.h -- LZMA Decoder 2 2009-02-07 : Igor Pavlov : Public domain */ 3 4 #ifndef __LZMA_DEC_H 5 #define __LZMA_DEC_H 6 7 #include "Types.h" 8 9 #ifdef __cplusplus 10 extern "C" { 11 #endif 12 13 /* #define _LZMA_PROB32 */ 14 /* _LZMA_PROB32 can increase the speed on some CPUs, 15 but memory usage for CLzmaDec::probs will be doubled in that case */ 16 17 #ifdef _LZMA_PROB32 18 #define CLzmaProb UInt32 19 #else 20 #define CLzmaProb UInt16 21 #endif 22 23 24 /* ---------- LZMA Properties ---------- */ 25 26 #define LZMA_PROPS_SIZE 5 27 28 typedef struct _CLzmaProps 29 { 30 unsigned lc, lp, pb; 31 UInt32 dicSize; 32 } CLzmaProps; 33 34 /* LzmaProps_Decode - decodes properties 35 Returns: 36 SZ_OK 37 SZ_ERROR_UNSUPPORTED - Unsupported properties 38 */ 39 40 SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size); 41 42 43 /* ---------- LZMA Decoder state ---------- */ 44 45 /* LZMA_REQUIRED_INPUT_MAX = number of required input bytes for worst case. 46 Num bits = log2((2^11 / 31) ^ 22) + 26 < 134 + 26 = 160; */ 47 48 #define LZMA_REQUIRED_INPUT_MAX 20 49 50 typedef struct 51 { 52 CLzmaProps prop; 53 CLzmaProb *probs; 54 Byte *dic; 55 const Byte *buf; 56 UInt32 range, code; 57 SizeT dicPos; 58 SizeT dicBufSize; 59 UInt32 processedPos; 60 UInt32 checkDicSize; 61 unsigned state; 62 UInt32 reps[4]; 63 unsigned remainLen; 64 int needFlush; 65 int needInitState; 66 UInt32 numProbs; 67 unsigned tempBufSize; 68 Byte tempBuf[LZMA_REQUIRED_INPUT_MAX]; 69 } CLzmaDec; 70 71 #define LzmaDec_Construct(p) { (p)->dic = 0; (p)->probs = 0; } 72 73 void LzmaDec_Init(CLzmaDec *p); 74 75 /* There are two types of LZMA streams: 76 0) Stream with end mark. That end mark adds about 6 bytes to compressed size. 77 1) Stream without end mark. You must know exact uncompressed size to decompress such stream. */ 78 79 typedef enum 80 { 81 LZMA_FINISH_ANY, /* finish at any point */ 82 LZMA_FINISH_END /* block must be finished at the end */ 83 } ELzmaFinishMode; 84 85 /* ELzmaFinishMode has meaning only if the decoding reaches output limit !!! 86 87 You must use LZMA_FINISH_END, when you know that current output buffer 88 covers last bytes of block. In other cases you must use LZMA_FINISH_ANY. 89 90 If LZMA decoder sees end marker before reaching output limit, it returns SZ_OK, 91 and output value of destLen will be less than output buffer size limit. 92 You can check status result also. 93 94 You can use multiple checks to test data integrity after full decompression: 95 1) Check Result and "status" variable. 96 2) Check that output(destLen) = uncompressedSize, if you know real uncompressedSize. 97 3) Check that output(srcLen) = compressedSize, if you know real compressedSize. 98 You must use correct finish mode in that case. */ 99 100 typedef enum 101 { 102 LZMA_STATUS_NOT_SPECIFIED, /* use main error code instead */ 103 LZMA_STATUS_FINISHED_WITH_MARK, /* stream was finished with end mark. */ 104 LZMA_STATUS_NOT_FINISHED, /* stream was not finished */ 105 LZMA_STATUS_NEEDS_MORE_INPUT, /* you must provide more input bytes */ 106 LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK /* there is probability that stream was finished without end mark */ 107 } ELzmaStatus; 108 109 /* ELzmaStatus is used only as output value for function call */ 110 111 112 /* ---------- Interfaces ---------- */ 113 114 /* There are 3 levels of interfaces: 115 1) Dictionary Interface 116 2) Buffer Interface 117 3) One Call Interface 118 You can select any of these interfaces, but don't mix functions from different 119 groups for same object. */ 120 121 122 /* There are two variants to allocate state for Dictionary Interface: 123 1) LzmaDec_Allocate / LzmaDec_Free 124 2) LzmaDec_AllocateProbs / LzmaDec_FreeProbs 125 You can use variant 2, if you set dictionary buffer manually. 126 For Buffer Interface you must always use variant 1. 127 128 LzmaDec_Allocate* can return: 129 SZ_OK 130 SZ_ERROR_MEM - Memory allocation error 131 SZ_ERROR_UNSUPPORTED - Unsupported properties 132 */ 133 134 SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc); 135 void LzmaDec_FreeProbs(CLzmaDec *p, ISzAlloc *alloc); 136 137 SRes LzmaDec_Allocate(CLzmaDec *state, const Byte *prop, unsigned propsSize, ISzAlloc *alloc); 138 void LzmaDec_Free(CLzmaDec *state, ISzAlloc *alloc); 139 140 /* ---------- Dictionary Interface ---------- */ 141 142 /* You can use it, if you want to eliminate the overhead for data copying from 143 dictionary to some other external buffer. 144 You must work with CLzmaDec variables directly in this interface. 145 146 STEPS: 147 LzmaDec_Constr() 148 LzmaDec_Allocate() 149 for (each new stream) 150 { 151 LzmaDec_Init() 152 while (it needs more decompression) 153 { 154 LzmaDec_DecodeToDic() 155 use data from CLzmaDec::dic and update CLzmaDec::dicPos 156 } 157 } 158 LzmaDec_Free() 159 */ 160 161 /* LzmaDec_DecodeToDic 162 163 The decoding to internal dictionary buffer (CLzmaDec::dic). 164 You must manually update CLzmaDec::dicPos, if it reaches CLzmaDec::dicBufSize !!! 165 166 finishMode: 167 It has meaning only if the decoding reaches output limit (dicLimit). 168 LZMA_FINISH_ANY - Decode just dicLimit bytes. 169 LZMA_FINISH_END - Stream must be finished after dicLimit. 170 171 Returns: 172 SZ_OK 173 status: 174 LZMA_STATUS_FINISHED_WITH_MARK 175 LZMA_STATUS_NOT_FINISHED 176 LZMA_STATUS_NEEDS_MORE_INPUT 177 LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK 178 SZ_ERROR_DATA - Data error 179 */ 180 181 SRes LzmaDec_DecodeToDic(CLzmaDec *p, SizeT dicLimit, 182 const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status); 183 184 185 /* ---------- Buffer Interface ---------- */ 186 187 /* It's zlib-like interface. 188 See LzmaDec_DecodeToDic description for information about STEPS and return results, 189 but you must use LzmaDec_DecodeToBuf instead of LzmaDec_DecodeToDic and you don't need 190 to work with CLzmaDec variables manually. 191 192 finishMode: 193 It has meaning only if the decoding reaches output limit (*destLen). 194 LZMA_FINISH_ANY - Decode just destLen bytes. 195 LZMA_FINISH_END - Stream must be finished after (*destLen). 196 */ 197 198 SRes LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen, 199 const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status); 200 201 202 /* ---------- One Call Interface ---------- */ 203 204 /* LzmaDecode 205 206 finishMode: 207 It has meaning only if the decoding reaches output limit (*destLen). 208 LZMA_FINISH_ANY - Decode just destLen bytes. 209 LZMA_FINISH_END - Stream must be finished after (*destLen). 210 211 Returns: 212 SZ_OK 213 status: 214 LZMA_STATUS_FINISHED_WITH_MARK 215 LZMA_STATUS_NOT_FINISHED 216 LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK 217 SZ_ERROR_DATA - Data error 218 SZ_ERROR_MEM - Memory allocation error 219 SZ_ERROR_UNSUPPORTED - Unsupported properties 220 SZ_ERROR_INPUT_EOF - It needs more bytes in input buffer (src). 221 */ 222 223 SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen, 224 const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode, 225 ELzmaStatus *status, ISzAlloc *alloc); 226 227 #ifdef __cplusplus 228 } 229 #endif 230 231 #endif 232
