rlm@1: /* LzmaDec.h -- LZMA Decoder
rlm@1: 2008-10-04 : Igor Pavlov : Public domain */
rlm@1:
rlm@1: #ifndef __LZMADEC_H
rlm@1: #define __LZMADEC_H
rlm@1:
rlm@1: #include "Types.h"
rlm@1:
rlm@1: /* #define _LZMA_PROB32 */
rlm@1: /* _LZMA_PROB32 can increase the speed on some CPUs,
rlm@1: but memory usage for CLzmaDec::probs will be doubled in that case */
rlm@1:
rlm@1: #ifdef _LZMA_PROB32
rlm@1: #define CLzmaProb UInt32
rlm@1: #else
rlm@1: #define CLzmaProb UInt16
rlm@1: #endif
rlm@1:
rlm@1:
rlm@1: /* ---------- LZMA Properties ---------- */
rlm@1:
rlm@1: #define LZMA_PROPS_SIZE 5
rlm@1:
rlm@1: typedef struct _CLzmaProps
rlm@1: {
rlm@1: unsigned lc, lp, pb;
rlm@1: UInt32 dicSize;
rlm@1: } CLzmaProps;
rlm@1:
rlm@1: /* LzmaProps_Decode - decodes properties
rlm@1: Returns:
rlm@1: SZ_OK
rlm@1: SZ_ERROR_UNSUPPORTED - Unsupported properties
rlm@1: */
rlm@1:
rlm@1: SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size);
rlm@1:
rlm@1:
rlm@1: /* ---------- LZMA Decoder state ---------- */
rlm@1:
rlm@1: /* LZMA_REQUIRED_INPUT_MAX = number of required input bytes for worst case.
rlm@1: Num bits = log2((2^11 / 31) ^ 22) + 26 < 134 + 26 = 160; */
rlm@1:
rlm@1: #define LZMA_REQUIRED_INPUT_MAX 20
rlm@1:
rlm@1: typedef struct
rlm@1: {
rlm@1: CLzmaProps prop;
rlm@1: CLzmaProb *probs;
rlm@1: Byte *dic;
rlm@1: const Byte *buf;
rlm@1: UInt32 range, code;
rlm@1: SizeT dicPos;
rlm@1: SizeT dicBufSize;
rlm@1: UInt32 processedPos;
rlm@1: UInt32 checkDicSize;
rlm@1: unsigned state;
rlm@1: UInt32 reps[4];
rlm@1: unsigned remainLen;
rlm@1: int needFlush;
rlm@1: int needInitState;
rlm@1: UInt32 numProbs;
rlm@1: unsigned tempBufSize;
rlm@1: Byte tempBuf[LZMA_REQUIRED_INPUT_MAX];
rlm@1: } CLzmaDec;
rlm@1:
rlm@1: #define LzmaDec_Construct(p) { (p)->dic = 0; (p)->probs = 0; }
rlm@1:
rlm@1: void LzmaDec_Init(CLzmaDec *p);
rlm@1:
rlm@1: /* There are two types of LZMA streams:
rlm@1: 0) Stream with end mark. That end mark adds about 6 bytes to compressed size.
rlm@1: 1) Stream without end mark. You must know exact uncompressed size to decompress such stream. */
rlm@1:
rlm@1: typedef enum
rlm@1: {
rlm@1: LZMA_FINISH_ANY, /* finish at any point */
rlm@1: LZMA_FINISH_END /* block must be finished at the end */
rlm@1: } ELzmaFinishMode;
rlm@1:
rlm@1: /* ELzmaFinishMode has meaning only if the decoding reaches output limit !!!
rlm@1:
rlm@1: You must use LZMA_FINISH_END, when you know that current output buffer
rlm@1: covers last bytes of block. In other cases you must use LZMA_FINISH_ANY.
rlm@1:
rlm@1: If LZMA decoder sees end marker before reaching output limit, it returns SZ_OK,
rlm@1: and output value of destLen will be less than output buffer size limit.
rlm@1: You can check status result also.
rlm@1:
rlm@1: You can use multiple checks to test data integrity after full decompression:
rlm@1: 1) Check Result and "status" variable.
rlm@1: 2) Check that output(destLen) = uncompressedSize, if you know real uncompressedSize.
rlm@1: 3) Check that output(srcLen) = compressedSize, if you know real compressedSize.
rlm@1: You must use correct finish mode in that case. */
rlm@1:
rlm@1: typedef enum
rlm@1: {
rlm@1: LZMA_STATUS_NOT_SPECIFIED, /* use main error code instead */
rlm@1: LZMA_STATUS_FINISHED_WITH_MARK, /* stream was finished with end mark. */
rlm@1: LZMA_STATUS_NOT_FINISHED, /* stream was not finished */
rlm@1: LZMA_STATUS_NEEDS_MORE_INPUT, /* you must provide more input bytes */
rlm@1: LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK /* there is probability that stream was finished without end mark */
rlm@1: } ELzmaStatus;
rlm@1:
rlm@1: /* ELzmaStatus is used only as output value for function call */
rlm@1:
rlm@1:
rlm@1: /* ---------- Interfaces ---------- */
rlm@1:
rlm@1: /* There are 3 levels of interfaces:
rlm@1: 1) Dictionary Interface
rlm@1: 2) Buffer Interface
rlm@1: 3) One Call Interface
rlm@1: You can select any of these interfaces, but don't mix functions from different
rlm@1: groups for same object. */
rlm@1:
rlm@1:
rlm@1: /* There are two variants to allocate state for Dictionary Interface:
rlm@1: 1) LzmaDec_Allocate / LzmaDec_Free
rlm@1: 2) LzmaDec_AllocateProbs / LzmaDec_FreeProbs
rlm@1: You can use variant 2, if you set dictionary buffer manually.
rlm@1: For Buffer Interface you must always use variant 1.
rlm@1:
rlm@1: LzmaDec_Allocate* can return:
rlm@1: SZ_OK
rlm@1: SZ_ERROR_MEM - Memory allocation error
rlm@1: SZ_ERROR_UNSUPPORTED - Unsupported properties
rlm@1: */
rlm@1:
rlm@1: SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc);
rlm@1: void LzmaDec_FreeProbs(CLzmaDec *p, ISzAlloc *alloc);
rlm@1:
rlm@1: SRes LzmaDec_Allocate(CLzmaDec *state, const Byte *prop, unsigned propsSize, ISzAlloc *alloc);
rlm@1: void LzmaDec_Free(CLzmaDec *state, ISzAlloc *alloc);
rlm@1:
rlm@1: /* ---------- Dictionary Interface ---------- */
rlm@1:
rlm@1: /* You can use it, if you want to eliminate the overhead for data copying from
rlm@1: dictionary to some other external buffer.
rlm@1: You must work with CLzmaDec variables directly in this interface.
rlm@1:
rlm@1: STEPS:
rlm@1: LzmaDec_Constr()
rlm@1: LzmaDec_Allocate()
rlm@1: for (each new stream)
rlm@1: {
rlm@1: LzmaDec_Init()
rlm@1: while (it needs more decompression)
rlm@1: {
rlm@1: LzmaDec_DecodeToDic()
rlm@1: use data from CLzmaDec::dic and update CLzmaDec::dicPos
rlm@1: }
rlm@1: }
rlm@1: LzmaDec_Free()
rlm@1: */
rlm@1:
rlm@1: /* LzmaDec_DecodeToDic
rlm@1:
rlm@1: The decoding to internal dictionary buffer (CLzmaDec::dic).
rlm@1: You must manually update CLzmaDec::dicPos, if it reaches CLzmaDec::dicBufSize !!!
rlm@1:
rlm@1: finishMode:
rlm@1: It has meaning only if the decoding reaches output limit (dicLimit).
rlm@1: LZMA_FINISH_ANY - Decode just dicLimit bytes.
rlm@1: LZMA_FINISH_END - Stream must be finished after dicLimit.
rlm@1:
rlm@1: Returns:
rlm@1: SZ_OK
rlm@1: status:
rlm@1: LZMA_STATUS_FINISHED_WITH_MARK
rlm@1: LZMA_STATUS_NOT_FINISHED
rlm@1: LZMA_STATUS_NEEDS_MORE_INPUT
rlm@1: LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
rlm@1: SZ_ERROR_DATA - Data error
rlm@1: */
rlm@1:
rlm@1: SRes LzmaDec_DecodeToDic(CLzmaDec *p, SizeT dicLimit,
rlm@1: const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status);
rlm@1:
rlm@1:
rlm@1: /* ---------- Buffer Interface ---------- */
rlm@1:
rlm@1: /* It's zlib-like interface.
rlm@1: See LzmaDec_DecodeToDic description for information about STEPS and return results,
rlm@1: but you must use LzmaDec_DecodeToBuf instead of LzmaDec_DecodeToDic and you don't need
rlm@1: to work with CLzmaDec variables manually.
rlm@1:
rlm@1: finishMode:
rlm@1: It has meaning only if the decoding reaches output limit (*destLen).
rlm@1: LZMA_FINISH_ANY - Decode just destLen bytes.
rlm@1: LZMA_FINISH_END - Stream must be finished after (*destLen).
rlm@1: */
rlm@1:
rlm@1: SRes LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen,
rlm@1: const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status);
rlm@1:
rlm@1:
rlm@1: /* ---------- One Call Interface ---------- */
rlm@1:
rlm@1: /* LzmaDecode
rlm@1:
rlm@1: finishMode:
rlm@1: It has meaning only if the decoding reaches output limit (*destLen).
rlm@1: LZMA_FINISH_ANY - Decode just destLen bytes.
rlm@1: LZMA_FINISH_END - Stream must be finished after (*destLen).
rlm@1:
rlm@1: Returns:
rlm@1: SZ_OK
rlm@1: status:
rlm@1: LZMA_STATUS_FINISHED_WITH_MARK
rlm@1: LZMA_STATUS_NOT_FINISHED
rlm@1: LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
rlm@1: SZ_ERROR_DATA - Data error
rlm@1: SZ_ERROR_MEM - Memory allocation error
rlm@1: SZ_ERROR_UNSUPPORTED - Unsupported properties
rlm@1: SZ_ERROR_INPUT_EOF - It needs more bytes in input buffer (src).
rlm@1: */
rlm@1:
rlm@1: SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
rlm@1: const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode,
rlm@1: ELzmaStatus *status, ISzAlloc *alloc);
rlm@1:
rlm@1: #endif