1/* LzmaDec.h -- LZMA Decoder
  22018-04-21 : Igor Pavlov : Public domain */
  3
  4#ifndef __LZMA_DEC_H
  5#define __LZMA_DEC_H
  6
  7#include "7zTypes.h"
  8
  9EXTERN_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
 15typedef
 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
 28typedef 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
 38Returns:
 39  SZ_OK
 40  SZ_ERROR_UNSUPPORTED - Unsupported properties
 41*/
 42
 43SRes 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
 53typedef 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
 78void 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
 84typedef 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
105typedef 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
133LzmaDec_Allocate* can return:
134  SZ_OK
135  SZ_ERROR_MEM         - Memory allocation error
136  SZ_ERROR_UNSUPPORTED - Unsupported properties
137*/
138   
139SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAllocPtr alloc);
140void LzmaDec_FreeProbs(CLzmaDec *p, ISzAllocPtr alloc);
141
142SRes LzmaDec_Allocate(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAllocPtr alloc);
143void 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
171finishMode:
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
176Returns:
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
186SRes 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
197finishMode:
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
203SRes 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
211finishMode:
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
216Returns:
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
228SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
229    const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode,
230    ELzmaStatus *status, ISzAllocPtr alloc);
231
232EXTERN_C_END
233
234#endif