b24e7fce |
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 |