Merge branch 'for-2.6.30' into for-2.6.31
[linux-2.6] / lib / decompress_unlzma.c
1 /* Lzma decompressor for Linux kernel. Shamelessly snarfed
2  *from busybox 1.1.1
3  *
4  *Linux kernel adaptation
5  *Copyright (C) 2006  Alain < alain@knaff.lu >
6  *
7  *Based on small lzma deflate implementation/Small range coder
8  *implementation for lzma.
9  *Copyright (C) 2006  Aurelien Jacobs < aurel@gnuage.org >
10  *
11  *Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
12  *Copyright (C) 1999-2005  Igor Pavlov
13  *
14  *Copyrights of the parts, see headers below.
15  *
16  *
17  *This program is free software; you can redistribute it and/or
18  *modify it under the terms of the GNU Lesser General Public
19  *License as published by the Free Software Foundation; either
20  *version 2.1 of the License, or (at your option) any later version.
21  *
22  *This program is distributed in the hope that it will be useful,
23  *but WITHOUT ANY WARRANTY; without even the implied warranty of
24  *MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
25  *Lesser General Public License for more details.
26  *
27  *You should have received a copy of the GNU Lesser General Public
28  *License along with this library; if not, write to the Free Software
29  *Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
30  */
31
32 #ifndef STATIC
33 #include <linux/decompress/unlzma.h>
34 #endif /* STATIC */
35
36 #include <linux/decompress/mm.h>
37 #include <linux/slab.h>
38
39 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
40
41 static long long INIT read_int(unsigned char *ptr, int size)
42 {
43         int i;
44         long long ret = 0;
45
46         for (i = 0; i < size; i++)
47                 ret = (ret << 8) | ptr[size-i-1];
48         return ret;
49 }
50
51 #define ENDIAN_CONVERT(x) \
52   x = (typeof(x))read_int((unsigned char *)&x, sizeof(x))
53
54
55 /* Small range coder implementation for lzma.
56  *Copyright (C) 2006  Aurelien Jacobs < aurel@gnuage.org >
57  *
58  *Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
59  *Copyright (c) 1999-2005  Igor Pavlov
60  */
61
62 #include <linux/compiler.h>
63
64 #define LZMA_IOBUF_SIZE 0x10000
65
66 struct rc {
67         int (*fill)(void*, unsigned int);
68         uint8_t *ptr;
69         uint8_t *buffer;
70         uint8_t *buffer_end;
71         int buffer_size;
72         uint32_t code;
73         uint32_t range;
74         uint32_t bound;
75 };
76
77
78 #define RC_TOP_BITS 24
79 #define RC_MOVE_BITS 5
80 #define RC_MODEL_TOTAL_BITS 11
81
82
83 /* Called twice: once at startup and once in rc_normalize() */
84 static void INIT rc_read(struct rc *rc)
85 {
86         rc->buffer_size = rc->fill((char *)rc->buffer, LZMA_IOBUF_SIZE);
87         if (rc->buffer_size <= 0)
88                 error("unexpected EOF");
89         rc->ptr = rc->buffer;
90         rc->buffer_end = rc->buffer + rc->buffer_size;
91 }
92
93 /* Called once */
94 static inline void INIT rc_init(struct rc *rc,
95                                        int (*fill)(void*, unsigned int),
96                                        char *buffer, int buffer_size)
97 {
98         rc->fill = fill;
99         rc->buffer = (uint8_t *)buffer;
100         rc->buffer_size = buffer_size;
101         rc->buffer_end = rc->buffer + rc->buffer_size;
102         rc->ptr = rc->buffer;
103
104         rc->code = 0;
105         rc->range = 0xFFFFFFFF;
106 }
107
108 static inline void INIT rc_init_code(struct rc *rc)
109 {
110         int i;
111
112         for (i = 0; i < 5; i++) {
113                 if (rc->ptr >= rc->buffer_end)
114                         rc_read(rc);
115                 rc->code = (rc->code << 8) | *rc->ptr++;
116         }
117 }
118
119
120 /* Called once. TODO: bb_maybe_free() */
121 static inline void INIT rc_free(struct rc *rc)
122 {
123         free(rc->buffer);
124 }
125
126 /* Called twice, but one callsite is in inline'd rc_is_bit_0_helper() */
127 static void INIT rc_do_normalize(struct rc *rc)
128 {
129         if (rc->ptr >= rc->buffer_end)
130                 rc_read(rc);
131         rc->range <<= 8;
132         rc->code = (rc->code << 8) | *rc->ptr++;
133 }
134 static inline void INIT rc_normalize(struct rc *rc)
135 {
136         if (rc->range < (1 << RC_TOP_BITS))
137                 rc_do_normalize(rc);
138 }
139
140 /* Called 9 times */
141 /* Why rc_is_bit_0_helper exists?
142  *Because we want to always expose (rc->code < rc->bound) to optimizer
143  */
144 static inline uint32_t INIT rc_is_bit_0_helper(struct rc *rc, uint16_t *p)
145 {
146         rc_normalize(rc);
147         rc->bound = *p * (rc->range >> RC_MODEL_TOTAL_BITS);
148         return rc->bound;
149 }
150 static inline int INIT rc_is_bit_0(struct rc *rc, uint16_t *p)
151 {
152         uint32_t t = rc_is_bit_0_helper(rc, p);
153         return rc->code < t;
154 }
155
156 /* Called ~10 times, but very small, thus inlined */
157 static inline void INIT rc_update_bit_0(struct rc *rc, uint16_t *p)
158 {
159         rc->range = rc->bound;
160         *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
161 }
162 static inline void rc_update_bit_1(struct rc *rc, uint16_t *p)
163 {
164         rc->range -= rc->bound;
165         rc->code -= rc->bound;
166         *p -= *p >> RC_MOVE_BITS;
167 }
168
169 /* Called 4 times in unlzma loop */
170 static int INIT rc_get_bit(struct rc *rc, uint16_t *p, int *symbol)
171 {
172         if (rc_is_bit_0(rc, p)) {
173                 rc_update_bit_0(rc, p);
174                 *symbol *= 2;
175                 return 0;
176         } else {
177                 rc_update_bit_1(rc, p);
178                 *symbol = *symbol * 2 + 1;
179                 return 1;
180         }
181 }
182
183 /* Called once */
184 static inline int INIT rc_direct_bit(struct rc *rc)
185 {
186         rc_normalize(rc);
187         rc->range >>= 1;
188         if (rc->code >= rc->range) {
189                 rc->code -= rc->range;
190                 return 1;
191         }
192         return 0;
193 }
194
195 /* Called twice */
196 static inline void INIT
197 rc_bit_tree_decode(struct rc *rc, uint16_t *p, int num_levels, int *symbol)
198 {
199         int i = num_levels;
200
201         *symbol = 1;
202         while (i--)
203                 rc_get_bit(rc, p + *symbol, symbol);
204         *symbol -= 1 << num_levels;
205 }
206
207
208 /*
209  * Small lzma deflate implementation.
210  * Copyright (C) 2006  Aurelien Jacobs < aurel@gnuage.org >
211  *
212  * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
213  * Copyright (C) 1999-2005  Igor Pavlov
214  */
215
216
217 struct lzma_header {
218         uint8_t pos;
219         uint32_t dict_size;
220         uint64_t dst_size;
221 } __attribute__ ((packed)) ;
222
223
224 #define LZMA_BASE_SIZE 1846
225 #define LZMA_LIT_SIZE 768
226
227 #define LZMA_NUM_POS_BITS_MAX 4
228
229 #define LZMA_LEN_NUM_LOW_BITS 3
230 #define LZMA_LEN_NUM_MID_BITS 3
231 #define LZMA_LEN_NUM_HIGH_BITS 8
232
233 #define LZMA_LEN_CHOICE 0
234 #define LZMA_LEN_CHOICE_2 (LZMA_LEN_CHOICE + 1)
235 #define LZMA_LEN_LOW (LZMA_LEN_CHOICE_2 + 1)
236 #define LZMA_LEN_MID (LZMA_LEN_LOW \
237                       + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS)))
238 #define LZMA_LEN_HIGH (LZMA_LEN_MID \
239                        +(1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS)))
240 #define LZMA_NUM_LEN_PROBS (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS))
241
242 #define LZMA_NUM_STATES 12
243 #define LZMA_NUM_LIT_STATES 7
244
245 #define LZMA_START_POS_MODEL_INDEX 4
246 #define LZMA_END_POS_MODEL_INDEX 14
247 #define LZMA_NUM_FULL_DISTANCES (1 << (LZMA_END_POS_MODEL_INDEX >> 1))
248
249 #define LZMA_NUM_POS_SLOT_BITS 6
250 #define LZMA_NUM_LEN_TO_POS_STATES 4
251
252 #define LZMA_NUM_ALIGN_BITS 4
253
254 #define LZMA_MATCH_MIN_LEN 2
255
256 #define LZMA_IS_MATCH 0
257 #define LZMA_IS_REP (LZMA_IS_MATCH + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
258 #define LZMA_IS_REP_G0 (LZMA_IS_REP + LZMA_NUM_STATES)
259 #define LZMA_IS_REP_G1 (LZMA_IS_REP_G0 + LZMA_NUM_STATES)
260 #define LZMA_IS_REP_G2 (LZMA_IS_REP_G1 + LZMA_NUM_STATES)
261 #define LZMA_IS_REP_0_LONG (LZMA_IS_REP_G2 + LZMA_NUM_STATES)
262 #define LZMA_POS_SLOT (LZMA_IS_REP_0_LONG \
263                        + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
264 #define LZMA_SPEC_POS (LZMA_POS_SLOT \
265                        +(LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS))
266 #define LZMA_ALIGN (LZMA_SPEC_POS \
267                     + LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX)
268 #define LZMA_LEN_CODER (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS))
269 #define LZMA_REP_LEN_CODER (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS)
270 #define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
271
272
273 struct writer {
274         uint8_t *buffer;
275         uint8_t previous_byte;
276         size_t buffer_pos;
277         int bufsize;
278         size_t global_pos;
279         int(*flush)(void*, unsigned int);
280         struct lzma_header *header;
281 };
282
283 struct cstate {
284         int state;
285         uint32_t rep0, rep1, rep2, rep3;
286 };
287
288 static inline size_t INIT get_pos(struct writer *wr)
289 {
290         return
291                 wr->global_pos + wr->buffer_pos;
292 }
293
294 static inline uint8_t INIT peek_old_byte(struct writer *wr,
295                                                 uint32_t offs)
296 {
297         if (!wr->flush) {
298                 int32_t pos;
299                 while (offs > wr->header->dict_size)
300                         offs -= wr->header->dict_size;
301                 pos = wr->buffer_pos - offs;
302                 return wr->buffer[pos];
303         } else {
304                 uint32_t pos = wr->buffer_pos - offs;
305                 while (pos >= wr->header->dict_size)
306                         pos += wr->header->dict_size;
307                 return wr->buffer[pos];
308         }
309
310 }
311
312 static inline void INIT write_byte(struct writer *wr, uint8_t byte)
313 {
314         wr->buffer[wr->buffer_pos++] = wr->previous_byte = byte;
315         if (wr->flush && wr->buffer_pos == wr->header->dict_size) {
316                 wr->buffer_pos = 0;
317                 wr->global_pos += wr->header->dict_size;
318                 wr->flush((char *)wr->buffer, wr->header->dict_size);
319         }
320 }
321
322
323 static inline void INIT copy_byte(struct writer *wr, uint32_t offs)
324 {
325         write_byte(wr, peek_old_byte(wr, offs));
326 }
327
328 static inline void INIT copy_bytes(struct writer *wr,
329                                          uint32_t rep0, int len)
330 {
331         do {
332                 copy_byte(wr, rep0);
333                 len--;
334         } while (len != 0 && wr->buffer_pos < wr->header->dst_size);
335 }
336
337 static inline void INIT process_bit0(struct writer *wr, struct rc *rc,
338                                      struct cstate *cst, uint16_t *p,
339                                      int pos_state, uint16_t *prob,
340                                      int lc, uint32_t literal_pos_mask) {
341         int mi = 1;
342         rc_update_bit_0(rc, prob);
343         prob = (p + LZMA_LITERAL +
344                 (LZMA_LIT_SIZE
345                  * (((get_pos(wr) & literal_pos_mask) << lc)
346                     + (wr->previous_byte >> (8 - lc))))
347                 );
348
349         if (cst->state >= LZMA_NUM_LIT_STATES) {
350                 int match_byte = peek_old_byte(wr, cst->rep0);
351                 do {
352                         int bit;
353                         uint16_t *prob_lit;
354
355                         match_byte <<= 1;
356                         bit = match_byte & 0x100;
357                         prob_lit = prob + 0x100 + bit + mi;
358                         if (rc_get_bit(rc, prob_lit, &mi)) {
359                                 if (!bit)
360                                         break;
361                         } else {
362                                 if (bit)
363                                         break;
364                         }
365                 } while (mi < 0x100);
366         }
367         while (mi < 0x100) {
368                 uint16_t *prob_lit = prob + mi;
369                 rc_get_bit(rc, prob_lit, &mi);
370         }
371         write_byte(wr, mi);
372         if (cst->state < 4)
373                 cst->state = 0;
374         else if (cst->state < 10)
375                 cst->state -= 3;
376         else
377                 cst->state -= 6;
378 }
379
380 static inline void INIT process_bit1(struct writer *wr, struct rc *rc,
381                                             struct cstate *cst, uint16_t *p,
382                                             int pos_state, uint16_t *prob) {
383   int offset;
384         uint16_t *prob_len;
385         int num_bits;
386         int len;
387
388         rc_update_bit_1(rc, prob);
389         prob = p + LZMA_IS_REP + cst->state;
390         if (rc_is_bit_0(rc, prob)) {
391                 rc_update_bit_0(rc, prob);
392                 cst->rep3 = cst->rep2;
393                 cst->rep2 = cst->rep1;
394                 cst->rep1 = cst->rep0;
395                 cst->state = cst->state < LZMA_NUM_LIT_STATES ? 0 : 3;
396                 prob = p + LZMA_LEN_CODER;
397         } else {
398                 rc_update_bit_1(rc, prob);
399                 prob = p + LZMA_IS_REP_G0 + cst->state;
400                 if (rc_is_bit_0(rc, prob)) {
401                         rc_update_bit_0(rc, prob);
402                         prob = (p + LZMA_IS_REP_0_LONG
403                                 + (cst->state <<
404                                    LZMA_NUM_POS_BITS_MAX) +
405                                 pos_state);
406                         if (rc_is_bit_0(rc, prob)) {
407                                 rc_update_bit_0(rc, prob);
408
409                                 cst->state = cst->state < LZMA_NUM_LIT_STATES ?
410                                         9 : 11;
411                                 copy_byte(wr, cst->rep0);
412                                 return;
413                         } else {
414                                 rc_update_bit_1(rc, prob);
415                         }
416                 } else {
417                         uint32_t distance;
418
419                         rc_update_bit_1(rc, prob);
420                         prob = p + LZMA_IS_REP_G1 + cst->state;
421                         if (rc_is_bit_0(rc, prob)) {
422                                 rc_update_bit_0(rc, prob);
423                                 distance = cst->rep1;
424                         } else {
425                                 rc_update_bit_1(rc, prob);
426                                 prob = p + LZMA_IS_REP_G2 + cst->state;
427                                 if (rc_is_bit_0(rc, prob)) {
428                                         rc_update_bit_0(rc, prob);
429                                         distance = cst->rep2;
430                                 } else {
431                                         rc_update_bit_1(rc, prob);
432                                         distance = cst->rep3;
433                                         cst->rep3 = cst->rep2;
434                                 }
435                                 cst->rep2 = cst->rep1;
436                         }
437                         cst->rep1 = cst->rep0;
438                         cst->rep0 = distance;
439                 }
440                 cst->state = cst->state < LZMA_NUM_LIT_STATES ? 8 : 11;
441                 prob = p + LZMA_REP_LEN_CODER;
442         }
443
444         prob_len = prob + LZMA_LEN_CHOICE;
445         if (rc_is_bit_0(rc, prob_len)) {
446                 rc_update_bit_0(rc, prob_len);
447                 prob_len = (prob + LZMA_LEN_LOW
448                             + (pos_state <<
449                                LZMA_LEN_NUM_LOW_BITS));
450                 offset = 0;
451                 num_bits = LZMA_LEN_NUM_LOW_BITS;
452         } else {
453                 rc_update_bit_1(rc, prob_len);
454                 prob_len = prob + LZMA_LEN_CHOICE_2;
455                 if (rc_is_bit_0(rc, prob_len)) {
456                         rc_update_bit_0(rc, prob_len);
457                         prob_len = (prob + LZMA_LEN_MID
458                                     + (pos_state <<
459                                        LZMA_LEN_NUM_MID_BITS));
460                         offset = 1 << LZMA_LEN_NUM_LOW_BITS;
461                         num_bits = LZMA_LEN_NUM_MID_BITS;
462                 } else {
463                         rc_update_bit_1(rc, prob_len);
464                         prob_len = prob + LZMA_LEN_HIGH;
465                         offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
466                                   + (1 << LZMA_LEN_NUM_MID_BITS));
467                         num_bits = LZMA_LEN_NUM_HIGH_BITS;
468                 }
469         }
470
471         rc_bit_tree_decode(rc, prob_len, num_bits, &len);
472         len += offset;
473
474         if (cst->state < 4) {
475                 int pos_slot;
476
477                 cst->state += LZMA_NUM_LIT_STATES;
478                 prob =
479                         p + LZMA_POS_SLOT +
480                         ((len <
481                           LZMA_NUM_LEN_TO_POS_STATES ? len :
482                           LZMA_NUM_LEN_TO_POS_STATES - 1)
483                          << LZMA_NUM_POS_SLOT_BITS);
484                 rc_bit_tree_decode(rc, prob,
485                                    LZMA_NUM_POS_SLOT_BITS,
486                                    &pos_slot);
487                 if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
488                         int i, mi;
489                         num_bits = (pos_slot >> 1) - 1;
490                         cst->rep0 = 2 | (pos_slot & 1);
491                         if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
492                                 cst->rep0 <<= num_bits;
493                                 prob = p + LZMA_SPEC_POS +
494                                         cst->rep0 - pos_slot - 1;
495                         } else {
496                                 num_bits -= LZMA_NUM_ALIGN_BITS;
497                                 while (num_bits--)
498                                         cst->rep0 = (cst->rep0 << 1) |
499                                                 rc_direct_bit(rc);
500                                 prob = p + LZMA_ALIGN;
501                                 cst->rep0 <<= LZMA_NUM_ALIGN_BITS;
502                                 num_bits = LZMA_NUM_ALIGN_BITS;
503                         }
504                         i = 1;
505                         mi = 1;
506                         while (num_bits--) {
507                                 if (rc_get_bit(rc, prob + mi, &mi))
508                                         cst->rep0 |= i;
509                                 i <<= 1;
510                         }
511                 } else
512                         cst->rep0 = pos_slot;
513                 if (++(cst->rep0) == 0)
514                         return;
515         }
516
517         len += LZMA_MATCH_MIN_LEN;
518
519         copy_bytes(wr, cst->rep0, len);
520 }
521
522
523
524 STATIC inline int INIT unlzma(unsigned char *buf, int in_len,
525                               int(*fill)(void*, unsigned int),
526                               int(*flush)(void*, unsigned int),
527                               unsigned char *output,
528                               int *posp,
529                               void(*error_fn)(char *x)
530         )
531 {
532         struct lzma_header header;
533         int lc, pb, lp;
534         uint32_t pos_state_mask;
535         uint32_t literal_pos_mask;
536         uint16_t *p;
537         int num_probs;
538         struct rc rc;
539         int i, mi;
540         struct writer wr;
541         struct cstate cst;
542         unsigned char *inbuf;
543         int ret = -1;
544
545         set_error_fn(error_fn);
546         if (!flush)
547                 in_len -= 4; /* Uncompressed size hack active in pre-boot
548                                 environment */
549         if (buf)
550                 inbuf = buf;
551         else
552                 inbuf = malloc(LZMA_IOBUF_SIZE);
553         if (!inbuf) {
554                 error("Could not allocate input bufer");
555                 goto exit_0;
556         }
557
558         cst.state = 0;
559         cst.rep0 = cst.rep1 = cst.rep2 = cst.rep3 = 1;
560
561         wr.header = &header;
562         wr.flush = flush;
563         wr.global_pos = 0;
564         wr.previous_byte = 0;
565         wr.buffer_pos = 0;
566
567         rc_init(&rc, fill, inbuf, in_len);
568
569         for (i = 0; i < sizeof(header); i++) {
570                 if (rc.ptr >= rc.buffer_end)
571                         rc_read(&rc);
572                 ((unsigned char *)&header)[i] = *rc.ptr++;
573         }
574
575         if (header.pos >= (9 * 5 * 5))
576                 error("bad header");
577
578         mi = 0;
579         lc = header.pos;
580         while (lc >= 9) {
581                 mi++;
582                 lc -= 9;
583         }
584         pb = 0;
585         lp = mi;
586         while (lp >= 5) {
587                 pb++;
588                 lp -= 5;
589         }
590         pos_state_mask = (1 << pb) - 1;
591         literal_pos_mask = (1 << lp) - 1;
592
593         ENDIAN_CONVERT(header.dict_size);
594         ENDIAN_CONVERT(header.dst_size);
595
596         if (header.dict_size == 0)
597                 header.dict_size = 1;
598
599         if (output)
600                 wr.buffer = output;
601         else {
602                 wr.bufsize = MIN(header.dst_size, header.dict_size);
603                 wr.buffer = large_malloc(wr.bufsize);
604         }
605         if (wr.buffer == NULL)
606                 goto exit_1;
607
608         num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
609         p = (uint16_t *) large_malloc(num_probs * sizeof(*p));
610         if (p == 0)
611                 goto exit_2;
612         num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
613         for (i = 0; i < num_probs; i++)
614                 p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
615
616         rc_init_code(&rc);
617
618         while (get_pos(&wr) < header.dst_size) {
619                 int pos_state = get_pos(&wr) & pos_state_mask;
620                 uint16_t *prob = p + LZMA_IS_MATCH +
621                         (cst.state << LZMA_NUM_POS_BITS_MAX) + pos_state;
622                 if (rc_is_bit_0(&rc, prob))
623                         process_bit0(&wr, &rc, &cst, p, pos_state, prob,
624                                      lc, literal_pos_mask);
625                 else {
626                         process_bit1(&wr, &rc, &cst, p, pos_state, prob);
627                         if (cst.rep0 == 0)
628                                 break;
629                 }
630         }
631
632         if (posp)
633                 *posp = rc.ptr-rc.buffer;
634         if (wr.flush)
635                 wr.flush(wr.buffer, wr.buffer_pos);
636         ret = 0;
637         large_free(p);
638 exit_2:
639         if (!output)
640                 large_free(wr.buffer);
641 exit_1:
642         if (!buf)
643                 free(inbuf);
644 exit_0:
645         return ret;
646 }
647
648 #define decompress unlzma