1/* LzmaDec.h -- LZMA Decoder
22009-02-07 : Igor Pavlov : Public domain */
3
4#ifndef __LZMA_DEC_H
5#define __LZMA_DEC_H
6
7#include "Types.h"
8
9#ifdef __cplusplus
10extern "C" {
11#endif
12
13/* #define _LZMA_PROB32 */
14/* _LZMA_PROB32 can increase the speed on some CPUs,
15   but memory usage for CLzmaDec::probs will be doubled in that case */
16
17#ifdef _LZMA_PROB32
18#define CLzmaProb UInt32
19#else
20#define CLzmaProb UInt16
21#endif
22
23
24/* ---------- LZMA Properties ---------- */
25
26#define LZMA_PROPS_SIZE 5
27
28typedef struct _CLzmaProps
29{
30  unsigned lc, lp, pb;
31  UInt32 dicSize;
32} CLzmaProps;
33
34/* LzmaProps_Decode - decodes properties
35Returns:
36  SZ_OK
37  SZ_ERROR_UNSUPPORTED - Unsupported properties
38*/
39
40SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size);
41
42
43/* ---------- LZMA Decoder state ---------- */
44
45/* LZMA_REQUIRED_INPUT_MAX = number of required input bytes for worst case.
46   Num bits = log2((2^11 / 31) ^ 22) + 26 < 134 + 26 = 160; */
47
48#define LZMA_REQUIRED_INPUT_MAX 20
49
50typedef struct
51{
52  CLzmaProps prop;
53  CLzmaProb *probs;
54  Byte *dic;
55  const Byte *buf;
56  UInt32 range, code;
57  SizeT dicPos;
58  SizeT dicBufSize;
59  UInt32 processedPos;
60  UInt32 checkDicSize;
61  unsigned state;
62  UInt32 reps[4];
63  unsigned remainLen;
64  int needFlush;
65  int needInitState;
66  UInt32 numProbs;
67  unsigned tempBufSize;
68  Byte tempBuf[LZMA_REQUIRED_INPUT_MAX];
69} CLzmaDec;
70
71#define LzmaDec_Construct(p) { (p)->dic = 0; (p)->probs = 0; }
72
73void LzmaDec_Init(CLzmaDec *p);
74
75/* There are two types of LZMA streams:
76     0) Stream with end mark. That end mark adds about 6 bytes to compressed size.
77     1) Stream without end mark. You must know exact uncompressed size to decompress such stream. */
78
79typedef enum
80{
81  LZMA_FINISH_ANY,   /* finish at any point */
82  LZMA_FINISH_END    /* block must be finished at the end */
83} ELzmaFinishMode;
84
85/* ELzmaFinishMode has meaning only if the decoding reaches output limit !!!
86
87   You must use LZMA_FINISH_END, when you know that current output buffer
88   covers last bytes of block. In other cases you must use LZMA_FINISH_ANY.
89
90   If LZMA decoder sees end marker before reaching output limit, it returns SZ_OK,
91   and output value of destLen will be less than output buffer size limit.
92   You can check status result also.
93
94   You can use multiple checks to test data integrity after full decompression:
95     1) Check Result and "status" variable.
96     2) Check that output(destLen) = uncompressedSize, if you know real uncompressedSize.
97     3) Check that output(srcLen) = compressedSize, if you know real compressedSize.
98        You must use correct finish mode in that case. */
99
100typedef enum
101{
102  LZMA_STATUS_NOT_SPECIFIED,               /* use main error code instead */
103  LZMA_STATUS_FINISHED_WITH_MARK,          /* stream was finished with end mark. */
104  LZMA_STATUS_NOT_FINISHED,                /* stream was not finished */
105  LZMA_STATUS_NEEDS_MORE_INPUT,            /* you must provide more input bytes */
106  LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK  /* there is probability that stream was finished without end mark */
107} ELzmaStatus;
108
109/* ELzmaStatus is used only as output value for function call */
110
111
112/* ---------- Interfaces ---------- */
113
114/* There are 3 levels of interfaces:
115     1) Dictionary Interface
116     2) Buffer Interface
117     3) One Call Interface
118   You can select any of these interfaces, but don't mix functions from different
119   groups for same object. */
120
121
122/* There are two variants to allocate state for Dictionary Interface:
123     1) LzmaDec_Allocate / LzmaDec_Free
124     2) LzmaDec_AllocateProbs / LzmaDec_FreeProbs
125   You can use variant 2, if you set dictionary buffer manually.
126   For Buffer Interface you must always use variant 1.
127
128LzmaDec_Allocate* can return:
129  SZ_OK
130  SZ_ERROR_MEM         - Memory allocation error
131  SZ_ERROR_UNSUPPORTED - Unsupported properties
132*/
133
134SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc);
135void LzmaDec_FreeProbs(CLzmaDec *p, ISzAlloc *alloc);
136
137SRes LzmaDec_Allocate(CLzmaDec *state, const Byte *prop, unsigned propsSize, ISzAlloc *alloc);
138void LzmaDec_Free(CLzmaDec *state, ISzAlloc *alloc);
139
140/* ---------- Dictionary Interface ---------- */
141
142/* You can use it, if you want to eliminate the overhead for data copying from
143   dictionary to some other external buffer.
144   You must work with CLzmaDec variables directly in this interface.
145
146   STEPS:
147     LzmaDec_Constr()
148     LzmaDec_Allocate()
149     for (each new stream)
150     {
151       LzmaDec_Init()
152       while (it needs more decompression)
153       {
154         LzmaDec_DecodeToDic()
155         use data from CLzmaDec::dic and update CLzmaDec::dicPos
156       }
157     }
158     LzmaDec_Free()
159*/
160
161/* LzmaDec_DecodeToDic
162
163   The decoding to internal dictionary buffer (CLzmaDec::dic).
164   You must manually update CLzmaDec::dicPos, if it reaches CLzmaDec::dicBufSize !!!
165
166finishMode:
167  It has meaning only if the decoding reaches output limit (dicLimit).
168  LZMA_FINISH_ANY - Decode just dicLimit bytes.
169  LZMA_FINISH_END - Stream must be finished after dicLimit.
170
171Returns:
172  SZ_OK
173    status:
174      LZMA_STATUS_FINISHED_WITH_MARK
175      LZMA_STATUS_NOT_FINISHED
176      LZMA_STATUS_NEEDS_MORE_INPUT
177      LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
178  SZ_ERROR_DATA - Data error
179*/
180
181SRes LzmaDec_DecodeToDic(CLzmaDec *p, SizeT dicLimit,
182    const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status);
183
184
185/* ---------- Buffer Interface ---------- */
186
187/* It's zlib-like interface.
188   See LzmaDec_DecodeToDic description for information about STEPS and return results,
189   but you must use LzmaDec_DecodeToBuf instead of LzmaDec_DecodeToDic and you don't need
190   to work with CLzmaDec variables manually.
191
192finishMode:
193  It has meaning only if the decoding reaches output limit (*destLen).
194  LZMA_FINISH_ANY - Decode just destLen bytes.
195  LZMA_FINISH_END - Stream must be finished after (*destLen).
196*/
197
198SRes LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen,
199    const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status);
200
201
202/* ---------- One Call Interface ---------- */
203
204/* LzmaDecode
205
206finishMode:
207  It has meaning only if the decoding reaches output limit (*destLen).
208  LZMA_FINISH_ANY - Decode just destLen bytes.
209  LZMA_FINISH_END - Stream must be finished after (*destLen).
210
211Returns:
212  SZ_OK
213    status:
214      LZMA_STATUS_FINISHED_WITH_MARK
215      LZMA_STATUS_NOT_FINISHED
216      LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK
217  SZ_ERROR_DATA - Data error
218  SZ_ERROR_MEM  - Memory allocation error
219  SZ_ERROR_UNSUPPORTED - Unsupported properties
220  SZ_ERROR_INPUT_EOF - It needs more bytes in input buffer (src).
221*/
222
223SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
224    const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode,
225    ELzmaStatus *status, ISzAlloc *alloc);
226
227#ifdef __cplusplus
228}
229#endif
230
231#endif
232