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Diffstat (limited to 'LzmaDec.h')
-rw-r--r-- | LzmaDec.h | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/LzmaDec.h b/LzmaDec.h new file mode 100644 index 0000000..59f7400 --- /dev/null +++ b/LzmaDec.h @@ -0,0 +1,90 @@ +/* LzmaDec.h -- LZMA Decoder +2009-02-07 : Igor Pavlov : Public domain */ + +/* ---------- LZMA Properties ---------- */ + +#define LZMA_PROPS_SIZE 5 + + +/* ---------- LZMA Decoder state ---------- */ + +/* LZMA_REQUIRED_INPUT_MAX = number of required input bytes for worst case. + Num bits = log2((2^11 / 31) ^ 22) + 26 < 134 + 26 = 160; */ + +#define LZMA_REQUIRED_INPUT_MAX 20 + +typedef struct +{ + int *probs; + uint8_t *dic; + const uint8_t *buf; + uint32_t range, code; + uint32_t dicPos; + uint32_t dicBufSize; + uint32_t processedPos; + uint32_t checkDicSize; + unsigned lc, lp, pb; + State state; + uint32_t reps[4]; + unsigned remainLen; + uint32_t numProbs; + unsigned tempBufSize; + bool needFlush; + uint8_t tempBuf[LZMA_REQUIRED_INPUT_MAX]; +} CLzmaDec; + + +/* There are two types of LZMA streams: + 0) Stream with end mark. That end mark adds about 6 bytes to compressed size. + 1) Stream without end mark. You must know exact uncompressed size to decompress such stream. */ + +typedef enum +{ + LZMA_FINISH_ANY, /* finish at any point */ + LZMA_FINISH_END /* block must be finished at the end */ +} ELzmaFinishMode; + +/* ELzmaFinishMode has meaning only if the decoding reaches output limit !!! + + You must use LZMA_FINISH_END, when you know that current output buffer + covers last bytes of block. In other cases you must use LZMA_FINISH_ANY. + + If LZMA decoder sees end marker before reaching output limit, it returns SZ_OK, + and output value of destLen will be less than output buffer size limit. + You can check status result also. + + You can use multiple checks to test data integrity after full decompression: + 1) Check Result and "status" variable. + 2) Check that output(destLen) = uncompressedSize, if you know real uncompressedSize. + 3) Check that output(srcLen) = compressedSize, if you know real compressedSize. + You must use correct finish mode in that case. */ + +typedef enum +{ + LZMA_STATUS_NOT_SPECIFIED, /* use main error code instead */ + LZMA_STATUS_FINISHED_WITH_MARK, /* stream was finished with end mark. */ + LZMA_STATUS_NOT_FINISHED, /* stream was not finished */ + LZMA_STATUS_NEEDS_MORE_INPUT, /* you must provide more input bytes */ + LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK /* there is probability that stream was finished without end mark */ +} ELzmaStatus; + +/* ELzmaStatus is used only as output value for function call */ + + +bool LzmaDec_Init(CLzmaDec *p, const uint8_t *raw_props); +void LzmaDec_Free(CLzmaDec *p); + + +/* ---------- Buffer Interface ---------- */ + +/* It's zlib-like interface. + +finishMode: + It has meaning only if the decoding reaches output limit (*destLen). + LZMA_FINISH_ANY - Decode just destLen bytes. + LZMA_FINISH_END - Stream must be finished after (*destLen). +*/ + +bool LzmaDec_DecodeToBuf( CLzmaDec *p, uint8_t *dest, uint32_t *destLen, + const uint8_t *src, uint32_t *srcLen, + ELzmaFinishMode finishMode, ELzmaStatus *status ); |