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-rw-r--r--archival/libunarchive/decompress_unlzma.c347
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diff --git a/archival/libunarchive/decompress_unlzma.c b/archival/libunarchive/decompress_unlzma.c
new file mode 100644
index 000000000..977cb48d0
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+++ b/archival/libunarchive/decompress_unlzma.c
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1/*
2 * Small lzma deflate implementation.
3 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
4 *
5 * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
6 * Copyright (C) 1999-2005 Igor Pavlov
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23#include <stdint.h>
24#include <unistd.h>
25#include <stdio.h>
26#include <byteswap.h>
27
28#include "libbb.h"
29
30#include "rangecoder.h"
31
32
33typedef struct {
34 uint8_t pos;
35 uint32_t dict_size;
36 uint64_t dst_size;
37} __attribute__ ((packed)) lzma_header_t;
38
39
40#define LZMA_BASE_SIZE 1846
41#define LZMA_LIT_SIZE 768
42
43#define LZMA_NUM_POS_BITS_MAX 4
44
45#define LZMA_LEN_NUM_LOW_BITS 3
46#define LZMA_LEN_NUM_MID_BITS 3
47#define LZMA_LEN_NUM_HIGH_BITS 8
48
49#define LZMA_LEN_CHOICE 0
50#define LZMA_LEN_CHOICE_2 (LZMA_LEN_CHOICE + 1)
51#define LZMA_LEN_LOW (LZMA_LEN_CHOICE_2 + 1)
52#define LZMA_LEN_MID (LZMA_LEN_LOW \
53 + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS)))
54#define LZMA_LEN_HIGH (LZMA_LEN_MID \
55 +(1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS)))
56#define LZMA_NUM_LEN_PROBS (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS))
57
58#define LZMA_NUM_STATES 12
59#define LZMA_NUM_LIT_STATES 7
60
61#define LZMA_START_POS_MODEL_INDEX 4
62#define LZMA_END_POS_MODEL_INDEX 14
63#define LZMA_NUM_FULL_DISTANCES (1 << (LZMA_END_POS_MODEL_INDEX >> 1))
64
65#define LZMA_NUM_POS_SLOT_BITS 6
66#define LZMA_NUM_LEN_TO_POS_STATES 4
67
68#define LZMA_NUM_ALIGN_BITS 4
69
70#define LZMA_MATCH_MIN_LEN 2
71
72#define LZMA_IS_MATCH 0
73#define LZMA_IS_REP (LZMA_IS_MATCH + (LZMA_NUM_STATES <<LZMA_NUM_POS_BITS_MAX))
74#define LZMA_IS_REP_G0 (LZMA_IS_REP + LZMA_NUM_STATES)
75#define LZMA_IS_REP_G1 (LZMA_IS_REP_G0 + LZMA_NUM_STATES)
76#define LZMA_IS_REP_G2 (LZMA_IS_REP_G1 + LZMA_NUM_STATES)
77#define LZMA_IS_REP_0_LONG (LZMA_IS_REP_G2 + LZMA_NUM_STATES)
78#define LZMA_POS_SLOT (LZMA_IS_REP_0_LONG \
79 + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
80#define LZMA_SPEC_POS (LZMA_POS_SLOT \
81 +(LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS))
82#define LZMA_ALIGN (LZMA_SPEC_POS \
83 + LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX)
84#define LZMA_LEN_CODER (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS))
85#define LZMA_REP_LEN_CODER (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS)
86#define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
87
88
89int unlzma(int src_fd, int dst_fd)
90{
91 lzma_header_t header;
92 int lc, pb, lp;
93 uint32_t pos_state_mask;
94 uint32_t literal_pos_mask;
95 uint32_t pos;
96 uint16_t *p;
97 uint16_t *prob;
98 uint16_t *prob_lit;
99 int num_bits;
100 int num_probs;
101 rc_t rc;
102 int i, mi;
103 uint8_t *buffer;
104 uint8_t previous_byte = 0;
105 size_t buffer_pos = 0, global_pos = 0;
106 int len = 0;
107 int state = 0;
108 uint32_t rep0 = 1, rep1 = 1, rep2 = 1, rep3 = 1;
109
110 if (read(src_fd, &header, sizeof(header)) != sizeof(header))
111 bb_error_msg_and_die("can't read header");
112
113 if (header.pos >= (9 * 5 * 5))
114 bb_error_msg_and_die("bad header");
115 mi = header.pos / 9;
116 lc = header.pos % 9;
117 pb = mi / 5;
118 lp = mi % 5;
119 pos_state_mask = (1 << pb) - 1;
120 literal_pos_mask = (1 << lp) - 1;
121
122#if __BYTE_ORDER == __BIG_ENDIAN
123 header.dict_size = bswap_32(header.dict_size);
124 header.dst_size = bswap_64(header.dst_size);
125#endif /* __BYTE_ORDER */
126
127 if (header.dict_size == 0)
128 header.dict_size = 1;
129
130 buffer = xmalloc(MIN(header.dst_size, header.dict_size));
131
132 num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
133 p = xmalloc(num_probs * sizeof(*p));
134 num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
135 for (i = 0; i < num_probs; i++)
136 p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
137
138 rc_init(&rc, src_fd, 0x10000);
139
140 while (global_pos + buffer_pos < header.dst_size) {
141 int pos_state = (buffer_pos + global_pos) & pos_state_mask;
142
143 prob =
144 p + LZMA_IS_MATCH + (state << LZMA_NUM_POS_BITS_MAX) + pos_state;
145 if (rc_is_bit_0(&rc, prob)) {
146 mi = 1;
147 rc_update_bit_0(&rc, prob);
148 prob = (p + LZMA_LITERAL + (LZMA_LIT_SIZE
149 * ((((buffer_pos + global_pos) & literal_pos_mask) << lc)
150 + (previous_byte >> (8 - lc)))));
151
152 if (state >= LZMA_NUM_LIT_STATES) {
153 int match_byte;
154
155 pos = buffer_pos - rep0;
156 while (pos >= header.dict_size)
157 pos += header.dict_size;
158 match_byte = buffer[pos];
159 do {
160 int bit;
161
162 match_byte <<= 1;
163 bit = match_byte & 0x100;
164 prob_lit = prob + 0x100 + bit + mi;
165 if (rc_get_bit(&rc, prob_lit, &mi)) {
166 if (!bit)
167 break;
168 } else {
169 if (bit)
170 break;
171 }
172 } while (mi < 0x100);
173 }
174 while (mi < 0x100) {
175 prob_lit = prob + mi;
176 rc_get_bit(&rc, prob_lit, &mi);
177 }
178 previous_byte = (uint8_t) mi;
179
180 buffer[buffer_pos++] = previous_byte;
181 if (buffer_pos == header.dict_size) {
182 buffer_pos = 0;
183 global_pos += header.dict_size;
184 write(dst_fd, buffer, header.dict_size);
185 }
186 if (state < 4)
187 state = 0;
188 else if (state < 10)
189 state -= 3;
190 else
191 state -= 6;
192 } else {
193 int offset;
194 uint16_t *prob_len;
195
196 rc_update_bit_1(&rc, prob);
197 prob = p + LZMA_IS_REP + state;
198 if (rc_is_bit_0(&rc, prob)) {
199 rc_update_bit_0(&rc, prob);
200 rep3 = rep2;
201 rep2 = rep1;
202 rep1 = rep0;
203 state = state < LZMA_NUM_LIT_STATES ? 0 : 3;
204 prob = p + LZMA_LEN_CODER;
205 } else {
206 rc_update_bit_1(&rc, prob);
207 prob = p + LZMA_IS_REP_G0 + state;
208 if (rc_is_bit_0(&rc, prob)) {
209 rc_update_bit_0(&rc, prob);
210 prob = (p + LZMA_IS_REP_0_LONG
211 + (state << LZMA_NUM_POS_BITS_MAX) + pos_state);
212 if (rc_is_bit_0(&rc, prob)) {
213 rc_update_bit_0(&rc, prob);
214
215 state = state < LZMA_NUM_LIT_STATES ? 9 : 11;
216 pos = buffer_pos - rep0;
217 while (pos >= header.dict_size)
218 pos += header.dict_size;
219 previous_byte = buffer[pos];
220 buffer[buffer_pos++] = previous_byte;
221 if (buffer_pos == header.dict_size) {
222 buffer_pos = 0;
223 global_pos += header.dict_size;
224 write(dst_fd, buffer, header.dict_size);
225 }
226 continue;
227 } else {
228 rc_update_bit_1(&rc, prob);
229 }
230 } else {
231 uint32_t distance;
232
233 rc_update_bit_1(&rc, prob);
234 prob = p + LZMA_IS_REP_G1 + state;
235 if (rc_is_bit_0(&rc, prob)) {
236 rc_update_bit_0(&rc, prob);
237 distance = rep1;
238 } else {
239 rc_update_bit_1(&rc, prob);
240 prob = p + LZMA_IS_REP_G2 + state;
241 if (rc_is_bit_0(&rc, prob)) {
242 rc_update_bit_0(&rc, prob);
243 distance = rep2;
244 } else {
245 rc_update_bit_1(&rc, prob);
246 distance = rep3;
247 rep3 = rep2;
248 }
249 rep2 = rep1;
250 }
251 rep1 = rep0;
252 rep0 = distance;
253 }
254 state = state < LZMA_NUM_LIT_STATES ? 8 : 11;
255 prob = p + LZMA_REP_LEN_CODER;
256 }
257
258 prob_len = prob + LZMA_LEN_CHOICE;
259 if (rc_is_bit_0(&rc, prob_len)) {
260 rc_update_bit_0(&rc, prob_len);
261 prob_len = (prob + LZMA_LEN_LOW
262 + (pos_state << LZMA_LEN_NUM_LOW_BITS));
263 offset = 0;
264 num_bits = LZMA_LEN_NUM_LOW_BITS;
265 } else {
266 rc_update_bit_1(&rc, prob_len);
267 prob_len = prob + LZMA_LEN_CHOICE_2;
268 if (rc_is_bit_0(&rc, prob_len)) {
269 rc_update_bit_0(&rc, prob_len);
270 prob_len = (prob + LZMA_LEN_MID
271 + (pos_state << LZMA_LEN_NUM_MID_BITS));
272 offset = 1 << LZMA_LEN_NUM_LOW_BITS;
273 num_bits = LZMA_LEN_NUM_MID_BITS;
274 } else {
275 rc_update_bit_1(&rc, prob_len);
276 prob_len = prob + LZMA_LEN_HIGH;
277 offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
278 + (1 << LZMA_LEN_NUM_MID_BITS));
279 num_bits = LZMA_LEN_NUM_HIGH_BITS;
280 }
281 }
282 rc_bit_tree_decode(&rc, prob_len, num_bits, &len);
283 len += offset;
284
285 if (state < 4) {
286 int pos_slot;
287
288 state += LZMA_NUM_LIT_STATES;
289 prob =
290 p + LZMA_POS_SLOT +
291 ((len <
292 LZMA_NUM_LEN_TO_POS_STATES ? len :
293 LZMA_NUM_LEN_TO_POS_STATES - 1)
294 << LZMA_NUM_POS_SLOT_BITS);
295 rc_bit_tree_decode(&rc, prob, LZMA_NUM_POS_SLOT_BITS,
296 &pos_slot);
297 if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
298 num_bits = (pos_slot >> 1) - 1;
299 rep0 = 2 | (pos_slot & 1);
300 if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
301 rep0 <<= num_bits;
302 prob = p + LZMA_SPEC_POS + rep0 - pos_slot - 1;
303 } else {
304 num_bits -= LZMA_NUM_ALIGN_BITS;
305 while (num_bits--)
306 rep0 = (rep0 << 1) | rc_direct_bit(&rc);
307 prob = p + LZMA_ALIGN;
308 rep0 <<= LZMA_NUM_ALIGN_BITS;
309 num_bits = LZMA_NUM_ALIGN_BITS;
310 }
311 i = 1;
312 mi = 1;
313 while (num_bits--) {
314 if (rc_get_bit(&rc, prob + mi, &mi))
315 rep0 |= i;
316 i <<= 1;
317 }
318 } else
319 rep0 = pos_slot;
320 if (++rep0 == 0)
321 break;
322 }
323
324 len += LZMA_MATCH_MIN_LEN;
325
326 do {
327 pos = buffer_pos - rep0;
328 while (pos >= header.dict_size)
329 pos += header.dict_size;
330 previous_byte = buffer[pos];
331 buffer[buffer_pos++] = previous_byte;
332 if (buffer_pos == header.dict_size) {
333 buffer_pos = 0;
334 global_pos += header.dict_size;
335 write(dst_fd, buffer, header.dict_size);
336 }
337 len--;
338 } while (len != 0 && buffer_pos < header.dst_size);
339 }
340 }
341
342 write(dst_fd, buffer, buffer_pos);
343 rc_free(&rc);
344 return 0;
345}
346
347/* vi:set ts=4: */
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