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File indexing completed on 2024-04-06 12:14:06
0001 /* LzmaDec.h -- LZMA Decoder 0002 2009-02-07 : Igor Pavlov : Public domain */ 0003 0004 #ifndef __LZMA_DEC_H 0005 #define __LZMA_DEC_H 0006 0007 #include "Types.h" 0008 0009 #ifdef __cplusplus 0010 extern "C" { 0011 #endif 0012 0013 /* #define _LZMA_PROB32 */ 0014 /* _LZMA_PROB32 can increase the speed on some CPUs, 0015 but memory usage for CLzmaDec::probs will be doubled in that case */ 0016 0017 #ifdef _LZMA_PROB32 0018 #define CLzmaProb UInt32 0019 #else 0020 #define CLzmaProb UInt16 0021 #endif 0022 0023 /* ---------- LZMA Properties ---------- */ 0024 0025 #define LZMA_PROPS_SIZE 5 0026 0027 typedef struct _CLzmaProps { 0028 unsigned lc, lp, pb; 0029 UInt32 dicSize; 0030 } CLzmaProps; 0031 0032 /* LzmaProps_Decode - decodes properties 0033 Returns: 0034 SZ_OK 0035 SZ_ERROR_UNSUPPORTED - Unsupported properties 0036 */ 0037 0038 SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size); 0039 0040 /* ---------- LZMA Decoder state ---------- */ 0041 0042 /* LZMA_REQUIRED_INPUT_MAX = number of required input bytes for worst case. 0043 Num bits = log2((2^11 / 31) ^ 22) + 26 < 134 + 26 = 160; */ 0044 0045 #define LZMA_REQUIRED_INPUT_MAX 20 0046 0047 typedef struct { 0048 CLzmaProps prop; 0049 CLzmaProb *probs; 0050 Byte *dic; 0051 const Byte *buf; 0052 UInt32 range, code; 0053 SizeT dicPos; 0054 SizeT dicBufSize; 0055 UInt32 processedPos; 0056 UInt32 checkDicSize; 0057 unsigned state; 0058 UInt32 reps[4]; 0059 unsigned remainLen; 0060 int needFlush; 0061 int needInitState; 0062 UInt32 numProbs; 0063 unsigned tempBufSize; 0064 Byte tempBuf[LZMA_REQUIRED_INPUT_MAX]; 0065 } CLzmaDec; 0066 0067 #define LzmaDec_Construct(p) \ 0068 { \ 0069 (p)->dic = 0; \ 0070 (p)->probs = 0; \ 0071 } 0072 0073 void LzmaDec_Init(CLzmaDec *p); 0074 0075 /* There are two types of LZMA streams: 0076 0) Stream with end mark. That end mark adds about 6 bytes to compressed size. 0077 1) Stream without end mark. You must know exact uncompressed size to decompress such stream. */ 0078 0079 typedef enum { 0080 LZMA_FINISH_ANY, /* finish at any point */ 0081 LZMA_FINISH_END /* block must be finished at the end */ 0082 } ELzmaFinishMode; 0083 0084 /* ELzmaFinishMode has meaning only if the decoding reaches output limit !!! 0085 0086 You must use LZMA_FINISH_END, when you know that current output buffer 0087 covers last bytes of block. In other cases you must use LZMA_FINISH_ANY. 0088 0089 If LZMA decoder sees end marker before reaching output limit, it returns SZ_OK, 0090 and output value of destLen will be less than output buffer size limit. 0091 You can check status result also. 0092 0093 You can use multiple checks to test data integrity after full decompression: 0094 1) Check Result and "status" variable. 0095 2) Check that output(destLen) = uncompressedSize, if you know real uncompressedSize. 0096 3) Check that output(srcLen) = compressedSize, if you know real compressedSize. 0097 You must use correct finish mode in that case. */ 0098 0099 typedef enum { 0100 LZMA_STATUS_NOT_SPECIFIED, /* use main error code instead */ 0101 LZMA_STATUS_FINISHED_WITH_MARK, /* stream was finished with end mark. */ 0102 LZMA_STATUS_NOT_FINISHED, /* stream was not finished */ 0103 LZMA_STATUS_NEEDS_MORE_INPUT, /* you must provide more input bytes */ 0104 LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK /* there is probability that stream was finished without end mark */ 0105 } ELzmaStatus; 0106 0107 /* ELzmaStatus is used only as output value for function call */ 0108 0109 /* ---------- Interfaces ---------- */ 0110 0111 /* There are 3 levels of interfaces: 0112 1) Dictionary Interface 0113 2) Buffer Interface 0114 3) One Call Interface 0115 You can select any of these interfaces, but don't mix functions from different 0116 groups for same object. */ 0117 0118 /* There are two variants to allocate state for Dictionary Interface: 0119 1) LzmaDec_Allocate / LzmaDec_Free 0120 2) LzmaDec_AllocateProbs / LzmaDec_FreeProbs 0121 You can use variant 2, if you set dictionary buffer manually. 0122 For Buffer Interface you must always use variant 1. 0123 0124 LzmaDec_Allocate* can return: 0125 SZ_OK 0126 SZ_ERROR_MEM - Memory allocation error 0127 SZ_ERROR_UNSUPPORTED - Unsupported properties 0128 */ 0129 0130 SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc); 0131 void LzmaDec_FreeProbs(CLzmaDec *p, ISzAlloc *alloc); 0132 0133 SRes LzmaDec_Allocate(CLzmaDec *state, const Byte *prop, unsigned propsSize, ISzAlloc *alloc); 0134 void LzmaDec_Free(CLzmaDec *state, ISzAlloc *alloc); 0135 0136 /* ---------- Dictionary Interface ---------- */ 0137 0138 /* You can use it, if you want to eliminate the overhead for data copying from 0139 dictionary to some other external buffer. 0140 You must work with CLzmaDec variables directly in this interface. 0141 0142 STEPS: 0143 LzmaDec_Constr() 0144 LzmaDec_Allocate() 0145 for (each new stream) 0146 { 0147 LzmaDec_Init() 0148 while (it needs more decompression) 0149 { 0150 LzmaDec_DecodeToDic() 0151 use data from CLzmaDec::dic and update CLzmaDec::dicPos 0152 } 0153 } 0154 LzmaDec_Free() 0155 */ 0156 0157 /* LzmaDec_DecodeToDic 0158 0159 The decoding to internal dictionary buffer (CLzmaDec::dic). 0160 You must manually update CLzmaDec::dicPos, if it reaches CLzmaDec::dicBufSize !!! 0161 0162 finishMode: 0163 It has meaning only if the decoding reaches output limit (dicLimit). 0164 LZMA_FINISH_ANY - Decode just dicLimit bytes. 0165 LZMA_FINISH_END - Stream must be finished after dicLimit. 0166 0167 Returns: 0168 SZ_OK 0169 status: 0170 LZMA_STATUS_FINISHED_WITH_MARK 0171 LZMA_STATUS_NOT_FINISHED 0172 LZMA_STATUS_NEEDS_MORE_INPUT 0173 LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK 0174 SZ_ERROR_DATA - Data error 0175 */ 0176 0177 SRes LzmaDec_DecodeToDic( 0178 CLzmaDec *p, SizeT dicLimit, const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status); 0179 0180 /* ---------- Buffer Interface ---------- */ 0181 0182 /* It's zlib-like interface. 0183 See LzmaDec_DecodeToDic description for information about STEPS and return results, 0184 but you must use LzmaDec_DecodeToBuf instead of LzmaDec_DecodeToDic and you don't need 0185 to work with CLzmaDec variables manually. 0186 0187 finishMode: 0188 It has meaning only if the decoding reaches output limit (*destLen). 0189 LZMA_FINISH_ANY - Decode just destLen bytes. 0190 LZMA_FINISH_END - Stream must be finished after (*destLen). 0191 */ 0192 0193 SRes LzmaDec_DecodeToBuf(CLzmaDec *p, 0194 Byte *dest, 0195 SizeT *destLen, 0196 const Byte *src, 0197 SizeT *srcLen, 0198 ELzmaFinishMode finishMode, 0199 ELzmaStatus *status); 0200 0201 /* ---------- One Call Interface ---------- */ 0202 0203 /* LzmaDecode 0204 0205 finishMode: 0206 It has meaning only if the decoding reaches output limit (*destLen). 0207 LZMA_FINISH_ANY - Decode just destLen bytes. 0208 LZMA_FINISH_END - Stream must be finished after (*destLen). 0209 0210 Returns: 0211 SZ_OK 0212 status: 0213 LZMA_STATUS_FINISHED_WITH_MARK 0214 LZMA_STATUS_NOT_FINISHED 0215 LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK 0216 SZ_ERROR_DATA - Data error 0217 SZ_ERROR_MEM - Memory allocation error 0218 SZ_ERROR_UNSUPPORTED - Unsupported properties 0219 SZ_ERROR_INPUT_EOF - It needs more bytes in input buffer (src). 0220 */ 0221 0222 SRes LzmaDecode(Byte *dest, 0223 SizeT *destLen, 0224 const Byte *src, 0225 SizeT *srcLen, 0226 const Byte *propData, 0227 unsigned propSize, 0228 ELzmaFinishMode finishMode, 0229 ELzmaStatus *status, 0230 ISzAlloc *alloc); 0231 0232 #ifdef __cplusplus 0233 } 0234 #endif 0235 0236 #endif
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