include/grub/lib/LzmaDec.h

   1 /*
   2  *  GRUB  --  GRand Unified Bootloader
   3  *  Copyright (c) 1999-2008 Igor Pavlov
   4  *  Copyright (C) 2008  Free Software Foundation, Inc.
   5  *
   6  *  GRUB is free software: you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  GRUB is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 /*
  21  * This code was taken from LZMA SDK 4.58 beta, and was slightly modified
  22  * to adapt it to GRUB's requirement.
  23  *
  24  * See <http://www.7-zip.org>, for more information about LZMA.
  25  */
  26
  27 #ifndef __LZMADEC_H
  28 #define __LZMADEC_H
  29
  30 #include "Types.h"
  31
  32 /* #define _LZMA_PROB32 */
  33 /* _LZMA_PROB32 can increase the speed on some CPUs,
  34    but memory usage for CLzmaDec::probs will be doubled in that case */
  35
  36 #ifdef _LZMA_PROB32
  37 #define CLzmaProb UInt32
  38 #else
  39 #define CLzmaProb UInt16
  40 #endif
  41
  42
  43 /* ---------- LZMA Properties ---------- */
  44
  45 #define LZMA_PROPS_SIZE 5
  46
  47 typedef struct _CLzmaProps
  48 {
  49   unsigned lc, lp, pb;
  50   UInt32 dicSize;
  51 } CLzmaProps;
  52
  53 /* LzmaProps_Decode - decodes properties
  54 Returns:
  55   SZ_OK
  56   SZ_ERROR_UNSUPPORTED - Unsupported properties
  57 */
  58
  59 SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size);
  60
  61
  62 /* ---------- LZMA Decoder state ---------- */
  63
  64 /* LZMA_REQUIRED_INPUT_MAX = number of required input bytes for worst case.
  65    Num bits = log2((2^11 / 31) ^ 22) + 26 < 134 + 26 = 160; */
  66
  67 #define LZMA_REQUIRED_INPUT_MAX 20
  68
  69 typedef struct
  70 {
  71   CLzmaProps prop;
  72   CLzmaProb *probs;
  73   Byte *dic;
  74   const Byte *buf;
  75   UInt32 range, code;
  76   SizeT dicPos;
  77   SizeT dicBufSize;
  78   UInt32 processedPos;
  79   UInt32 checkDicSize;
  80   unsigned state;
  81   UInt32 reps[4];
  82   unsigned remainLen;
  83   int needFlush;
  84   int needInitState;
  85   UInt32 numProbs;
  86   unsigned tempBufSize;
  87   Byte tempBuf[LZMA_REQUIRED_INPUT_MAX];
  88 } CLzmaDec;
  89
  90 #define LzmaDec_Construct(p) { (p)->dic = 0; (p)->probs = 0; }
  91
  92 void LzmaDec_Init(CLzmaDec *p);
  93
  94 /* There are two types of LZMA streams:
  95      0) Stream with end mark. That end mark adds about 6 bytes to compressed size.
  96      1) Stream without end mark. You must know exact uncompressed size to decompress such stream. */
  97
  98 typedef enum
  99 {
 100   LZMA_FINISH_ANY,   /* finish at any point */
 101   LZMA_FINISH_END    /* block must be finished at the end */
 102 } ELzmaFinishMode;
 103
 104 /* ELzmaFinishMode has meaning only if the decoding reaches output limit !!!
 105
 106    You must use LZMA_FINISH_END, when you know that current output buffer
 107    covers last bytes of block. In other cases you must use LZMA_FINISH_ANY.
 108
 109    If LZMA decoder sees end marker before reaching output limit, it returns SZ_OK,
 110    and output value of destLen will be less than output buffer size limit.
 111    You can check status result also.
 112
 113    You can use multiple checks to test data integrity after full decompression:
 114      1) Check Result and "status" variable.
 115      2) Check that output(destLen) = uncompressedSize, if you know real uncompressedSize.
 116      3) Check that output(srcLen) = compressedSize, if you know real compressedSize.
 117         You must use correct finish mode in that case. */
 118
 119 typedef enum
 120 {
 121   LZMA_STATUS_NOT_SPECIFIED,               /* use main error code instead */
 122   LZMA_STATUS_FINISHED_WITH_MARK,          /* stream was finished with end mark. */
 123   LZMA_STATUS_NOT_FINISHED,                /* stream was not finished */
 124   LZMA_STATUS_NEEDS_MORE_INPUT,            /* you must provide more input bytes */
 125   LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK  /* there is probability that stream was finished without end mark */
 126 } ELzmaStatus;
 127
 128 /* ELzmaStatus is used only as output value for function call */
 129
 130
 131 /* ---------- Interfaces ---------- */
 132
 133 /* There are 3 levels of interfaces:
 134      1) Dictionary Interface
 135      2) Buffer Interface
 136      3) One Call Interface
 137    You can select any of these interfaces, but don't mix functions from different
 138    groups for same object. */
 139
 140
 141 /* There are two variants to allocate state for Dictionary Interface:
 142      1) LzmaDec_Allocate / LzmaDec_Free
 143      2) LzmaDec_AllocateProbs / LzmaDec_FreeProbs
 144    You can use variant 2, if you set dictionary buffer manually.
 145    For Buffer Interface you must always use variant 1.
 146
 147 LzmaDec_Allocate* can return:
 148   SZ_OK
 149   SZ_ERROR_MEM         - Memory allocation error
 150   SZ_ERROR_UNSUPPORTED - Unsupported properties
 151 */
 152
 153 SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc);
 154 void LzmaDec_FreeProbs(CLzmaDec *p, ISzAlloc *alloc);
 155
 156 SRes LzmaDec_Allocate(CLzmaDec *state, const Byte *prop, unsigned propsSize, ISzAlloc *alloc);
 157 void LzmaDec_Free(CLzmaDec *state, ISzAlloc *alloc);
 158
 159 /* ---------- Dictionary Interface ---------- */
 160
 161 /* You can use it, if you want to eliminate the overhead for data copying from
 162    dictionary to some other external buffer.
 163    You must work with CLzmaDec variables directly in this interface.
 164
 165    STEPS:
 166      LzmaDec_Constr()
 167      LzmaDec_Allocate()
 168      for (each new stream)
 169      {
 170        LzmaDec_Init()
 171        while (it needs more decompression)
 172        {
 173          LzmaDec_DecodeToDic()
 174          use data from CLzmaDec::dic and update CLzmaDec::dicPos
 175        }
 176      }
 177      LzmaDec_Free()
 178 */
 179
 180 /* LzmaDec_DecodeToDic
 181
 182    The decoding to internal dictionary buffer (CLzmaDec::dic).
 183    You must manually update CLzmaDec::dicPos, if it reaches CLzmaDec::dicBufSize !!!
 184
 185 finishMode:
 186   It has meaning only if the decoding reaches output limit (dicLimit).
 187   LZMA_FINISH_ANY - Decode just dicLimit bytes.
 188   LZMA_FINISH_END - Stream must be finished after dicLimit.
 189
 190 Returns:
 191   SZ_OK
 192     status:
 193       LZMA_STATUS_FINISHED_WITH_MARK
 194       LZMA_STATUS_NOT_FINISHED
 195       LZMA_STATUS_NEEDS_MORE_INPUT
 196       LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
 197   SZ_ERROR_DATA - Data error
 198 */
 199
 200 SRes LzmaDec_DecodeToDic(CLzmaDec *p, SizeT dicLimit,
 201     const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status);
 202
 203
 204 /* ---------- Buffer Interface ---------- */
 205
 206 /* It's zlib-like interface.
 207    See LzmaDec_DecodeToDic description for information about STEPS and return results,
 208    but you must use LzmaDec_DecodeToBuf instead of LzmaDec_DecodeToDic and you don't need
 209    to work with CLzmaDec variables manually.
 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
 217 SRes LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen,
 218     const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status);
 219
 220
 221 /* ---------- One Call Interface ---------- */
 222
 223 /* LzmaDecode
 224
 225 finishMode:
 226   It has meaning only if the decoding reaches output limit (*destLen).
 227   LZMA_FINISH_ANY - Decode just destLen bytes.
 228   LZMA_FINISH_END - Stream must be finished after (*destLen).
 229
 230 Returns:
 231   SZ_OK
 232     status:
 233       LZMA_STATUS_FINISHED_WITH_MARK
 234       LZMA_STATUS_NOT_FINISHED
 235       LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
 236   SZ_ERROR_DATA - Data error
 237   SZ_ERROR_MEM  - Memory allocation error
 238   SZ_ERROR_UNSUPPORTED - Unsupported properties
 239   SZ_ERROR_INPUT_EOF - It needs more bytes in input buffer (src).
 240 */
 241
 242 SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
 243     const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode,
 244     ELzmaStatus *status, ISzAlloc *alloc);
 245
 246 #endif