nel/3rdparty/seven_zip/LzmaDec.h

   1 /* LzmaDec.h -- LZMA Decoder
   2 2018-04-21 : Igor Pavlov : Public domain */
   3
   4 #ifndef __LZMA_DEC_H
   5 #define __LZMA_DEC_H
   6
   7 #include "7zTypes.h"
   8
   9 EXTERN_C_BEGIN
  10
  11 /* #define _LZMA_PROB32 */
  12 /* _LZMA_PROB32 can increase the speed on some CPUs,
  13    but memory usage for CLzmaDec::probs will be doubled in that case */
  14
  15 typedef
  16 #ifdef _LZMA_PROB32
  17   UInt32
  18 #else
  19   UInt16
  20 #endif
  21   CLzmaProb;
  22
  23
  24 /* ---------- LZMA Properties ---------- */
  25
  26 #define LZMA_PROPS_SIZE 5
  27
  28 typedef struct _CLzmaProps
  29 {
  30   Byte lc;
  31   Byte lp;
  32   Byte pb;
  33   Byte _pad_;
  34   UInt32 dicSize;
  35 } CLzmaProps;
  36
  37 /* LzmaProps_Decode - decodes properties
  38 Returns:
  39   SZ_OK
  40   SZ_ERROR_UNSUPPORTED - Unsupported properties
  41 */
  42
  43 SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size);
  44
  45
  46 /* ---------- LZMA Decoder state ---------- */
  47
  48 /* LZMA_REQUIRED_INPUT_MAX = number of required input bytes for worst case.
  49    Num bits = log2((2^11 / 31) ^ 22) + 26 < 134 + 26 = 160; */
  50
  51 #define LZMA_REQUIRED_INPUT_MAX 20
  52
  53 typedef struct
  54 {
  55   /* Don't change this structure. ASM code can use it. */
  56   CLzmaProps prop;
  57   CLzmaProb *probs;
  58   CLzmaProb *probs_1664;
  59   Byte *dic;
  60   SizeT dicBufSize;
  61   SizeT dicPos;
  62   const Byte *buf;
  63   UInt32 range;
  64   UInt32 code;
  65   UInt32 processedPos;
  66   UInt32 checkDicSize;
  67   UInt32 reps[4];
  68   UInt32 state;
  69   UInt32 remainLen;
  70
  71   UInt32 numProbs;
  72   unsigned tempBufSize;
  73   Byte tempBuf[LZMA_REQUIRED_INPUT_MAX];
  74 } CLzmaDec;
  75
  76 #define LzmaDec_Construct(p) { (p)->dic = NULL; (p)->probs = NULL; }
  77
  78 void LzmaDec_Init(CLzmaDec *p);
  79
  80 /* There are two types of LZMA streams:
  81      - Stream with end mark. That end mark adds about 6 bytes to compressed size.
  82      - Stream without end mark. You must know exact uncompressed size to decompress such stream. */
  83
  84 typedef enum
  85 {
  86   LZMA_FINISH_ANY,   /* finish at any point */
  87   LZMA_FINISH_END    /* block must be finished at the end */
  88 } ELzmaFinishMode;
  89
  90 /* ELzmaFinishMode has meaning only if the decoding reaches output limit !!!
  91
  92    You must use LZMA_FINISH_END, when you know that current output buffer
  93    covers last bytes of block. In other cases you must use LZMA_FINISH_ANY.
  94
  95    If LZMA decoder sees end marker before reaching output limit, it returns SZ_OK,
  96    and output value of destLen will be less than output buffer size limit.
  97    You can check status result also.
  98
  99    You can use multiple checks to test data integrity after full decompression:
 100      1) Check Result and "status" variable.
 101      2) Check that output(destLen) = uncompressedSize, if you know real uncompressedSize.
 102      3) Check that output(srcLen) = compressedSize, if you know real compressedSize.
 103         You must use correct finish mode in that case. */
 104
 105 typedef enum
 106 {
 107   LZMA_STATUS_NOT_SPECIFIED,               /* use main error code instead */
 108   LZMA_STATUS_FINISHED_WITH_MARK,          /* stream was finished with end mark. */
 109   LZMA_STATUS_NOT_FINISHED,                /* stream was not finished */
 110   LZMA_STATUS_NEEDS_MORE_INPUT,            /* you must provide more input bytes */
 111   LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK  /* there is probability that stream was finished without end mark */
 112 } ELzmaStatus;
 113
 114 /* ELzmaStatus is used only as output value for function call */
 115
 116
 117 /* ---------- Interfaces ---------- */
 118
 119 /* There are 3 levels of interfaces:
 120      1) Dictionary Interface
 121      2) Buffer Interface
 122      3) One Call Interface
 123    You can select any of these interfaces, but don't mix functions from different
 124    groups for same object. */
 125
 126
 127 /* There are two variants to allocate state for Dictionary Interface:
 128      1) LzmaDec_Allocate / LzmaDec_Free
 129      2) LzmaDec_AllocateProbs / LzmaDec_FreeProbs
 130    You can use variant 2, if you set dictionary buffer manually.
 131    For Buffer Interface you must always use variant 1.
 132
 133 LzmaDec_Allocate* can return:
 134   SZ_OK
 135   SZ_ERROR_MEM         - Memory allocation error
 136   SZ_ERROR_UNSUPPORTED - Unsupported properties
 137 */
 138
 139 SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAllocPtr alloc);
 140 void LzmaDec_FreeProbs(CLzmaDec *p, ISzAllocPtr alloc);
 141
 142 SRes LzmaDec_Allocate(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAllocPtr alloc);
 143 void LzmaDec_Free(CLzmaDec *p, ISzAllocPtr alloc);
 144
 145 /* ---------- Dictionary Interface ---------- */
 146
 147 /* You can use it, if you want to eliminate the overhead for data copying from
 148    dictionary to some other external buffer.
 149    You must work with CLzmaDec variables directly in this interface.
 150
 151    STEPS:
 152      LzmaDec_Construct()
 153      LzmaDec_Allocate()
 154      for (each new stream)
 155      {
 156        LzmaDec_Init()
 157        while (it needs more decompression)
 158        {
 159          LzmaDec_DecodeToDic()
 160          use data from CLzmaDec::dic and update CLzmaDec::dicPos
 161        }
 162      }
 163      LzmaDec_Free()
 164 */
 165
 166 /* LzmaDec_DecodeToDic
 167
 168    The decoding to internal dictionary buffer (CLzmaDec::dic).
 169    You must manually update CLzmaDec::dicPos, if it reaches CLzmaDec::dicBufSize !!!
 170
 171 finishMode:
 172   It has meaning only if the decoding reaches output limit (dicLimit).
 173   LZMA_FINISH_ANY - Decode just dicLimit bytes.
 174   LZMA_FINISH_END - Stream must be finished after dicLimit.
 175
 176 Returns:
 177   SZ_OK
 178     status:
 179       LZMA_STATUS_FINISHED_WITH_MARK
 180       LZMA_STATUS_NOT_FINISHED
 181       LZMA_STATUS_NEEDS_MORE_INPUT
 182       LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
 183   SZ_ERROR_DATA - Data error
 184 */
 185
 186 SRes LzmaDec_DecodeToDic(CLzmaDec *p, SizeT dicLimit,
 187     const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status);
 188
 189
 190 /* ---------- Buffer Interface ---------- */
 191
 192 /* It's zlib-like interface.
 193    See LzmaDec_DecodeToDic description for information about STEPS and return results,
 194    but you must use LzmaDec_DecodeToBuf instead of LzmaDec_DecodeToDic and you don't need
 195    to work with CLzmaDec variables manually.
 196
 197 finishMode:
 198   It has meaning only if the decoding reaches output limit (*destLen).
 199   LZMA_FINISH_ANY - Decode just destLen bytes.
 200   LZMA_FINISH_END - Stream must be finished after (*destLen).
 201 */
 202
 203 SRes LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen,
 204     const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status);
 205
 206
 207 /* ---------- One Call Interface ---------- */
 208
 209 /* LzmaDecode
 210
 211 finishMode:
 212   It has meaning only if the decoding reaches output limit (*destLen).
 213   LZMA_FINISH_ANY - Decode just destLen bytes.
 214   LZMA_FINISH_END - Stream must be finished after (*destLen).
 215
 216 Returns:
 217   SZ_OK
 218     status:
 219       LZMA_STATUS_FINISHED_WITH_MARK
 220       LZMA_STATUS_NOT_FINISHED
 221       LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
 222   SZ_ERROR_DATA - Data error
 223   SZ_ERROR_MEM  - Memory allocation error
 224   SZ_ERROR_UNSUPPORTED - Unsupported properties
 225   SZ_ERROR_INPUT_EOF - It needs more bytes in input buffer (src).
 226 */
 227
 228 SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
 229     const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode,
 230     ELzmaStatus *status, ISzAllocPtr alloc);
 231
 232 EXTERN_C_END
 233
 234 #endif