util/cbfstool/lzma/C/LzmaDec.h

   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 typedef uint16_t CLzmaProb;
  10
  11 /* ---------- LZMA Properties ---------- */
  12
  13 #define LZMA_PROPS_SIZE 5
  14
  15 struct CLzmaProps
  16 {
  17   unsigned lc, lp, pb;
  18   uint32_t dicSize;
  19 };
  20
  21 /* LzmaProps_Decode - decodes properties
  22 Returns:
  23   SZ_OK
  24   SZ_ERROR_UNSUPPORTED - Unsupported properties
  25 */
  26
  27 SRes LzmaProps_Decode(struct CLzmaProps *p, const uint8_t *data, unsigned size);
  28
  29
  30 /* ---------- LZMA Decoder state ---------- */
  31
  32 /* LZMA_REQUIRED_INPUT_MAX = number of required input bytes for worst case.
  33    Num bits = log2((2^11 / 31) ^ 22) + 26 < 134 + 26 = 160; */
  34
  35 #define LZMA_REQUIRED_INPUT_MAX 20
  36
  37 struct CLzmaDec
  38 {
  39         struct CLzmaProps prop;
  40   CLzmaProb *probs;
  41   uint8_t *dic;
  42   const uint8_t *buf;
  43   uint32_t range, code;
  44   size_t dicPos;
  45   size_t dicBufSize;
  46   uint32_t processedPos;
  47   uint32_t checkDicSize;
  48   unsigned state;
  49   uint32_t reps[4];
  50   unsigned remainLen;
  51   int needFlush;
  52   int needInitState;
  53   uint32_t numProbs;
  54   unsigned tempBufSize;
  55   uint8_t tempBuf[LZMA_REQUIRED_INPUT_MAX];
  56 };
  57
  58 #define LzmaDec_Construct(p) { (p)->dic = 0; (p)->probs = 0; }
  59
  60 void LzmaDec_Init(struct CLzmaDec *p);
  61
  62 /* There are two types of LZMA streams:
  63      0) Stream with end mark. That end mark adds about 6 bytes to compressed size.
  64      1) Stream without end mark. You must know exact uncompressed size to decompress such stream. */
  65
  66 enum ELzmaFinishMode
  67 {
  68   LZMA_FINISH_ANY,   /* finish at any point */
  69   LZMA_FINISH_END    /* block must be finished at the end */
  70 };
  71
  72 /* ELzmaFinishMode has meaning only if the decoding reaches output limit !!!
  73
  74    You must use LZMA_FINISH_END, when you know that current output buffer
  75    covers last bytes of block. In other cases you must use LZMA_FINISH_ANY.
  76
  77    If LZMA decoder sees end marker before reaching output limit, it returns SZ_OK,
  78    and output value of destLen will be less than output buffer size limit.
  79    You can check status result also.
  80
  81    You can use multiple checks to test data integrity after full decompression:
  82      1) Check Result and "status" variable.
  83      2) Check that output(destLen) = uncompressedSize, if you know real uncompressedSize.
  84      3) Check that output(srcLen) = compressedSize, if you know real compressedSize.
  85         You must use correct finish mode in that case. */
  86
  87 enum ELzmaStatus
  88 {
  89   LZMA_STATUS_NOT_SPECIFIED,               /* use main error code instead */
  90   LZMA_STATUS_FINISHED_WITH_MARK,          /* stream was finished with end mark. */
  91   LZMA_STATUS_NOT_FINISHED,                /* stream was not finished */
  92   LZMA_STATUS_NEEDS_MORE_INPUT,            /* you must provide more input bytes */
  93   LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK  /* there is probability that stream was finished without end mark */
  94 };
  95
  96 /* ELzmaStatus is used only as output value for function call */
  97
  98
  99 /* ---------- Interfaces ---------- */
 100
 101 /* There are 3 levels of interfaces:
 102      1) Dictionary Interface
 103      2) Buffer Interface
 104      3) One Call Interface
 105    You can select any of these interfaces, but don't mix functions from different
 106    groups for same object. */
 107
 108
 109 /* There are two variants to allocate state for Dictionary Interface:
 110      1) LzmaDec_Allocate / LzmaDec_Free
 111      2) LzmaDec_AllocateProbs / LzmaDec_FreeProbs
 112    You can use variant 2, if you set dictionary buffer manually.
 113    For Buffer Interface you must always use variant 1.
 114
 115 LzmaDec_Allocate* can return:
 116   SZ_OK
 117   SZ_ERROR_MEM         - Memory allocation error
 118   SZ_ERROR_UNSUPPORTED - Unsupported properties
 119 */
 120
 121 SRes LzmaDec_AllocateProbs(struct CLzmaDec *p, const uint8_t *props, unsigned propsSize, struct ISzAlloc *alloc);
 122 void LzmaDec_FreeProbs(struct CLzmaDec *p, struct ISzAlloc *alloc);
 123
 124 SRes LzmaDec_Allocate(struct CLzmaDec *state, const uint8_t *prop, unsigned propsSize, struct ISzAlloc *alloc);
 125 void LzmaDec_Free(struct CLzmaDec *state, struct ISzAlloc *alloc);
 126
 127 /* ---------- Dictionary Interface ---------- */
 128
 129 /* You can use it, if you want to eliminate the overhead for data copying from
 130    dictionary to some other external buffer.
 131    You must work with CLzmaDec variables directly in this interface.
 132
 133    STEPS:
 134      LzmaDec_Constr()
 135      LzmaDec_Allocate()
 136      for (each new stream)
 137      {
 138        LzmaDec_Init()
 139        while (it needs more decompression)
 140        {
 141          LzmaDec_DecodeToDic()
 142          use data from CLzmaDec::dic and update CLzmaDec::dicPos
 143        }
 144      }
 145      LzmaDec_Free()
 146 */
 147
 148 /* LzmaDec_DecodeToDic
 149
 150    The decoding to internal dictionary buffer (CLzmaDec::dic).
 151    You must manually update CLzmaDec::dicPos, if it reaches CLzmaDec::dicBufSize !!!
 152
 153 finishMode:
 154   It has meaning only if the decoding reaches output limit (dicLimit).
 155   LZMA_FINISH_ANY - Decode just dicLimit bytes.
 156   LZMA_FINISH_END - Stream must be finished after dicLimit.
 157
 158 Returns:
 159   SZ_OK
 160     status:
 161       LZMA_STATUS_FINISHED_WITH_MARK
 162       LZMA_STATUS_NOT_FINISHED
 163       LZMA_STATUS_NEEDS_MORE_INPUT
 164       LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
 165   SZ_ERROR_DATA - Data error
 166 */
 167
 168 SRes LzmaDec_DecodeToDic(struct CLzmaDec *p, size_t dicLimit,
 169     const uint8_t *src, size_t *srcLen, enum ELzmaFinishMode finishMode, enum ELzmaStatus *status);
 170
 171
 172 /* ---------- Buffer Interface ---------- */
 173
 174 /* It's zlib-like interface.
 175    See LzmaDec_DecodeToDic description for information about STEPS and return results,
 176    but you must use LzmaDec_DecodeToBuf instead of LzmaDec_DecodeToDic and you don't need
 177    to work with CLzmaDec variables manually.
 178
 179 finishMode:
 180   It has meaning only if the decoding reaches output limit (*destLen).
 181   LZMA_FINISH_ANY - Decode just destLen bytes.
 182   LZMA_FINISH_END - Stream must be finished after (*destLen).
 183 */
 184
 185 SRes LzmaDec_DecodeToBuf(struct CLzmaDec *p, uint8_t *dest, size_t *destLen,
 186     const uint8_t *src, size_t *srcLen, enum ELzmaFinishMode finishMode, enum ELzmaStatus *status);
 187
 188
 189 /* ---------- One Call Interface ---------- */
 190
 191 /* LzmaDecode
 192
 193 finishMode:
 194   It has meaning only if the decoding reaches output limit (*destLen).
 195   LZMA_FINISH_ANY - Decode just destLen bytes.
 196   LZMA_FINISH_END - Stream must be finished after (*destLen).
 197
 198 Returns:
 199   SZ_OK
 200     status:
 201       LZMA_STATUS_FINISHED_WITH_MARK
 202       LZMA_STATUS_NOT_FINISHED
 203       LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
 204   SZ_ERROR_DATA - Data error
 205   SZ_ERROR_MEM  - Memory allocation error
 206   SZ_ERROR_UNSUPPORTED - Unsupported properties
 207   SZ_ERROR_INPUT_EOF - It needs more bytes in input buffer (src).
 208 */
 209
 210 SRes LzmaDecode(uint8_t *dest, size_t *destLen, const uint8_t *src, size_t *srcLen,
 211     const uint8_t *propData, unsigned propSize, enum ELzmaFinishMode finishMode,
 212     enum ELzmaStatus *status, struct ISzAlloc *alloc);
 213
 214 #endif