1/* LzmaDec.h -- LZMA Decoder
22008-10-04 : Igor Pavlov : Public domain */
3
4#ifndef __LZMADEC_H
5#define __LZMADEC_H
6
7#include "Types.h"
8
9/* #define _LZMA_PROB32 */
10/* _LZMA_PROB32 can increase the speed on some CPUs,
11   but memory usage for CLzmaDec::probs will be doubled in that case */
12
13#ifdef _LZMA_PROB32
14#define CLzmaProb UInt32
15#else
16#define CLzmaProb UInt16
17#endif
18
19
20/* ---------- LZMA Properties ---------- */
21
22#define LZMA_PROPS_SIZE 5
23
24typedef struct _CLzmaProps
25{
26  unsigned lc, lp, pb;
27  UInt32 dicSize;
28} CLzmaProps;
29
30/* LzmaProps_Decode - decodes properties
31Returns:
32  SZ_OK
33  SZ_ERROR_UNSUPPORTED - Unsupported properties
34*/
35
36SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size);
37
38
39/* ---------- LZMA Decoder state ---------- */
40
41/* LZMA_REQUIRED_INPUT_MAX = number of required input bytes for worst case.
42   Num bits = log2((2^11 / 31) ^ 22) + 26 < 134 + 26 = 160; */
43
44#define LZMA_REQUIRED_INPUT_MAX 20
45
46typedef struct
47{
48  CLzmaProps prop;
49  CLzmaProb *probs;
50  Byte *dic;
51  const Byte *buf;
52  UInt32 range, code;
53  SizeT dicPos;
54  SizeT dicBufSize;
55  UInt32 processedPos;
56  UInt32 checkDicSize;
57  unsigned state;
58  UInt32 reps[4];
59  unsigned remainLen;
60  int needFlush;
61  int needInitState;
62  UInt32 numProbs;
63  unsigned tempBufSize;
64  Byte tempBuf[LZMA_REQUIRED_INPUT_MAX];
65} CLzmaDec;
66
67#define LzmaDec_Construct(p) { (p)->dic = 0; (p)->probs = 0; }
68
69void LzmaDec_Init(CLzmaDec *p);
70
71/* There are two types of LZMA streams:
72     0) Stream with end mark. That end mark adds about 6 bytes to compressed size.
73     1) Stream without end mark. You must know exact uncompressed size to decompress such stream. */
74
75typedef enum
76{
77  LZMA_FINISH_ANY,   /* finish at any point */
78  LZMA_FINISH_END    /* block must be finished at the end */
79} ELzmaFinishMode;
80
81/* ELzmaFinishMode has meaning only if the decoding reaches output limit !!!
82
83   You must use LZMA_FINISH_END, when you know that current output buffer
84   covers last bytes of block. In other cases you must use LZMA_FINISH_ANY.
85
86   If LZMA decoder sees end marker before reaching output limit, it returns SZ_OK,
87   and output value of destLen will be less than output buffer size limit.
88   You can check status result also.
89
90   You can use multiple checks to test data integrity after full decompression:
91     1) Check Result and "status" variable.
92     2) Check that output(destLen) = uncompressedSize, if you know real uncompressedSize.
93     3) Check that output(srcLen) = compressedSize, if you know real compressedSize.
94        You must use correct finish mode in that case. */
95
96typedef enum
97{
98  LZMA_STATUS_NOT_SPECIFIED,               /* use main error code instead */
99  LZMA_STATUS_FINISHED_WITH_MARK,          /* stream was finished with end mark. */
100  LZMA_STATUS_NOT_FINISHED,                /* stream was not finished */
101  LZMA_STATUS_NEEDS_MORE_INPUT,            /* you must provide more input bytes */
102  LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK  /* there is probability that stream was finished without end mark */
103} ELzmaStatus;
104
105/* ELzmaStatus is used only as output value for function call */
106
107
108/* ---------- Interfaces ---------- */
109
110/* There are 3 levels of interfaces:
111     1) Dictionary Interface
112     2) Buffer Interface
113     3) One Call Interface
114   You can select any of these interfaces, but don't mix functions from different
115   groups for same object. */
116
117
118/* There are two variants to allocate state for Dictionary Interface:
119     1) LzmaDec_Allocate / LzmaDec_Free
120     2) LzmaDec_AllocateProbs / LzmaDec_FreeProbs
121   You can use variant 2, if you set dictionary buffer manually.
122   For Buffer Interface you must always use variant 1.
123
124LzmaDec_Allocate* can return:
125  SZ_OK
126  SZ_ERROR_MEM         - Memory allocation error
127  SZ_ERROR_UNSUPPORTED - Unsupported properties
128*/
129
130SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc);
131void LzmaDec_FreeProbs(CLzmaDec *p, ISzAlloc *alloc);
132
133SRes LzmaDec_Allocate(CLzmaDec *state, const Byte *prop, unsigned propsSize, ISzAlloc *alloc);
134void LzmaDec_Free(CLzmaDec *state, ISzAlloc *alloc);
135
136/* ---------- Dictionary Interface ---------- */
137
138/* You can use it, if you want to eliminate the overhead for data copying from
139   dictionary to some other external buffer.
140   You must work with CLzmaDec variables directly in this interface.
141
142   STEPS:
143     LzmaDec_Constr()
144     LzmaDec_Allocate()
145     for (each new stream)
146     {
147       LzmaDec_Init()
148       while (it needs more decompression)
149       {
150         LzmaDec_DecodeToDic()
151         use data from CLzmaDec::dic and update CLzmaDec::dicPos
152       }
153     }
154     LzmaDec_Free()
155*/
156
157/* LzmaDec_DecodeToDic
158
159   The decoding to internal dictionary buffer (CLzmaDec::dic).
160   You must manually update CLzmaDec::dicPos, if it reaches CLzmaDec::dicBufSize !!!
161
162finishMode:
163  It has meaning only if the decoding reaches output limit (dicLimit).
164  LZMA_FINISH_ANY - Decode just dicLimit bytes.
165  LZMA_FINISH_END - Stream must be finished after dicLimit.
166
167Returns:
168  SZ_OK
169    status:
170      LZMA_STATUS_FINISHED_WITH_MARK
171      LZMA_STATUS_NOT_FINISHED
172      LZMA_STATUS_NEEDS_MORE_INPUT
173      LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
174  SZ_ERROR_DATA - Data error
175*/
176
177SRes LzmaDec_DecodeToDic(CLzmaDec *p, SizeT dicLimit,
178    const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status);
179
180
181/* ---------- Buffer Interface ---------- */
182
183/* It's zlib-like interface.
184   See LzmaDec_DecodeToDic description for information about STEPS and return results,
185   but you must use LzmaDec_DecodeToBuf instead of LzmaDec_DecodeToDic and you don't need
186   to work with CLzmaDec variables manually.
187
188finishMode:
189  It has meaning only if the decoding reaches output limit (*destLen).
190  LZMA_FINISH_ANY - Decode just destLen bytes.
191  LZMA_FINISH_END - Stream must be finished after (*destLen).
192*/
193
194SRes LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen,
195    const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status);
196
197
198/* ---------- One Call Interface ---------- */
199
200/* LzmaDecode
201
202finishMode:
203  It has meaning only if the decoding reaches output limit (*destLen).
204  LZMA_FINISH_ANY - Decode just destLen bytes.
205  LZMA_FINISH_END - Stream must be finished after (*destLen).
206
207Returns:
208  SZ_OK
209    status:
210      LZMA_STATUS_FINISHED_WITH_MARK
211      LZMA_STATUS_NOT_FINISHED
212      LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
213  SZ_ERROR_DATA - Data error
214  SZ_ERROR_MEM  - Memory allocation error
215  SZ_ERROR_UNSUPPORTED - Unsupported properties
216  SZ_ERROR_INPUT_EOF - It needs more bytes in input buffer (src).
217*/
218
219SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
220    const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode,
221    ELzmaStatus *status, ISzAlloc *alloc);
222
223#endif
224