bzip2/lzma: library support for gzip, bzip2 and lzma decompression
[linux-2.6.git] / 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
38 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
39
40 static long long INIT read_int(unsigned char *ptr, int size)
41 {
42         int i;
43         long long ret = 0;
44
45         for (i = 0; i < size; i++)
46                 ret = (ret << 8) | ptr[size-i-1];
47         return ret;
48 }
49
50 #define ENDIAN_CONVERT(x) \
51   x = (typeof(x))read_int((unsigned char *)&x, sizeof(x))
52
53
54 /* Small range coder implementation for lzma.
55  *Copyright (C) 2006  Aurelien Jacobs < aurel@gnuage.org >
56  *
57  *Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
58  *Copyright (c) 1999-2005  Igor Pavlov
59  */
60
61 #include <linux/compiler.h>
62
63 #define LZMA_IOBUF_SIZE 0x10000
64
65 struct rc {
66         int (*fill)(void*, unsigned int);
67         uint8_t *ptr;
68         uint8_t *buffer;
69         uint8_t *buffer_end;
70         int buffer_size;
71         uint32_t code;
72         uint32_t range;
73         uint32_t bound;
74 };
75
76
77 #define RC_TOP_BITS 24
78 #define RC_MOVE_BITS 5
79 #define RC_MODEL_TOTAL_BITS 11
80
81
82 /* Called twice: once at startup and once in rc_normalize() */
83 static void INIT rc_read(struct rc *rc)
84 {
85         rc->buffer_size = rc->fill((char *)rc->buffer, LZMA_IOBUF_SIZE);
86         if (rc->buffer_size <= 0)
87                 error("unexpected EOF");
88         rc->ptr = rc->buffer;
89         rc->buffer_end = rc->buffer + rc->buffer_size;
90 }
91
92 /* Called once */
93 static inline void INIT rc_init(struct rc *rc,
94                                        int (*fill)(void*, unsigned int),
95                                        char *buffer, int buffer_size)
96 {
97         rc->fill = fill;
98         rc->buffer = (uint8_t *)buffer;
99         rc->buffer_size = buffer_size;
100         rc->buffer_end = rc->buffer + rc->buffer_size;
101         rc->ptr = rc->buffer;
102
103         rc->code = 0;
104         rc->range = 0xFFFFFFFF;
105 }
106
107 static inline void INIT rc_init_code(struct rc *rc)
108 {
109         int i;
110
111         for (i = 0; i < 5; i++) {
112                 if (rc->ptr >= rc->buffer_end)
113                         rc_read(rc);
114                 rc->code = (rc->code << 8) | *rc->ptr++;
115         }
116 }
117
118
119 /* Called once. TODO: bb_maybe_free() */
120 static inline void INIT rc_free(struct rc *rc)
121 {
122         free(rc->buffer);
123 }
124
125 /* Called twice, but one callsite is in inline'd rc_is_bit_0_helper() */
126 static void INIT rc_do_normalize(struct rc *rc)
127 {
128         if (rc->ptr >= rc->buffer_end)
129                 rc_read(rc);
130         rc->range <<= 8;
131         rc->code = (rc->code << 8) | *rc->ptr++;
132 }
133 static inline void INIT rc_normalize(struct rc *rc)
134 {
135         if (rc->range < (1 << RC_TOP_BITS))
136                 rc_do_normalize(rc);
137 }
138
139 /* Called 9 times */
140 /* Why rc_is_bit_0_helper exists?
141  *Because we want to always expose (rc->code < rc->bound) to optimizer
142  */
143 static inline uint32_t INIT rc_is_bit_0_helper(struct rc *rc, uint16_t *p)
144 {
145         rc_normalize(rc);
146         rc->bound = *p * (rc->range >> RC_MODEL_TOTAL_BITS);
147         return rc->bound;
148 }
149 static inline int INIT rc_is_bit_0(struct rc *rc, uint16_t *p)
150 {
151         uint32_t t = rc_is_bit_0_helper(rc, p);
152         return rc->code < t;
153 }
154
155 /* Called ~10 times, but very small, thus inlined */
156 static inline void INIT rc_update_bit_0(struct rc *rc, uint16_t *p)
157 {
158         rc->range = rc->bound;
159         *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
160 }
161 static inline void rc_update_bit_1(struct rc *rc, uint16_t *p)
162 {
163         rc->range -= rc->bound;
164         rc->code -= rc->bound;
165         *p -= *p >> RC_MOVE_BITS;
166 }
167
168 /* Called 4 times in unlzma loop */
169 static int INIT rc_get_bit(struct rc *rc, uint16_t *p, int *symbol)
170 {
171         if (rc_is_bit_0(rc, p)) {
172                 rc_update_bit_0(rc, p);
173                 *symbol *= 2;
174                 return 0;
175         } else {
176                 rc_update_bit_1(rc, p);
177                 *symbol = *symbol * 2 + 1;
178                 return 1;
179         }
180 }
181
182 /* Called once */
183 static inline int INIT rc_direct_bit(struct rc *rc)
184 {
185         rc_normalize(rc);
186         rc->range >>= 1;
187         if (rc->code >= rc->range) {
188                 rc->code -= rc->range;
189                 return 1;
190         }
191         return 0;
192 }
193
194 /* Called twice */
195 static inline void INIT
196 rc_bit_tree_decode(struct rc *rc, uint16_t *p, int num_levels, int *symbol)
197 {
198         int i = num_levels;
199
200         *symbol = 1;
201         while (i--)
202                 rc_get_bit(rc, p + *symbol, symbol);
203         *symbol -= 1 << num_levels;
204 }
205
206
207 /*
208  * Small lzma deflate implementation.
209  * Copyright (C) 2006  Aurelien Jacobs < aurel@gnuage.org >
210  *
211  * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
212  * Copyright (C) 1999-2005  Igor Pavlov
213  */
214
215
216 struct lzma_header {
217         uint8_t pos;
218         uint32_t dict_size;
219         uint64_t dst_size;
220 } __attribute__ ((packed)) ;
221
222
223 #define LZMA_BASE_SIZE 1846
224 #define LZMA_LIT_SIZE 768
225
226 #define LZMA_NUM_POS_BITS_MAX 4
227
228 #define LZMA_LEN_NUM_LOW_BITS 3
229 #define LZMA_LEN_NUM_MID_BITS 3
230 #define LZMA_LEN_NUM_HIGH_BITS 8
231
232 #define LZMA_LEN_CHOICE 0
233 #define LZMA_LEN_CHOICE_2 (LZMA_LEN_CHOICE + 1)
234 #define LZMA_LEN_LOW (LZMA_LEN_CHOICE_2 + 1)
235 #define LZMA_LEN_MID (LZMA_LEN_LOW \
236                       + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS)))
237 #define LZMA_LEN_HIGH (LZMA_LEN_MID \
238                        +(1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS)))
239 #define LZMA_NUM_LEN_PROBS (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS))
240
241 #define LZMA_NUM_STATES 12
242 #define LZMA_NUM_LIT_STATES 7
243
244 #define LZMA_START_POS_MODEL_INDEX 4
245 #define LZMA_END_POS_MODEL_INDEX 14
246 #define LZMA_NUM_FULL_DISTANCES (1 << (LZMA_END_POS_MODEL_INDEX >> 1))
247
248 #define LZMA_NUM_POS_SLOT_BITS 6
249 #define LZMA_NUM_LEN_TO_POS_STATES 4
250
251 #define LZMA_NUM_ALIGN_BITS 4
252
253 #define LZMA_MATCH_MIN_LEN 2
254
255 #define LZMA_IS_MATCH 0
256 #define LZMA_IS_REP (LZMA_IS_MATCH + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
257 #define LZMA_IS_REP_G0 (LZMA_IS_REP + LZMA_NUM_STATES)
258 #define LZMA_IS_REP_G1 (LZMA_IS_REP_G0 + LZMA_NUM_STATES)
259 #define LZMA_IS_REP_G2 (LZMA_IS_REP_G1 + LZMA_NUM_STATES)
260 #define LZMA_IS_REP_0_LONG (LZMA_IS_REP_G2 + LZMA_NUM_STATES)
261 #define LZMA_POS_SLOT (LZMA_IS_REP_0_LONG \
262                        + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
263 #define LZMA_SPEC_POS (LZMA_POS_SLOT \
264                        +(LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS))
265 #define LZMA_ALIGN (LZMA_SPEC_POS \
266                     + LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX)
267 #define LZMA_LEN_CODER (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS))
268 #define LZMA_REP_LEN_CODER (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS)
269 #define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
270
271
272 struct writer {
273         uint8_t *buffer;
274         uint8_t previous_byte;
275         size_t buffer_pos;
276         int bufsize;
277         size_t global_pos;
278         int(*flush)(void*, unsigned int);
279         struct lzma_header *header;
280 };
281
282 struct cstate {
283         int state;
284         uint32_t rep0, rep1, rep2, rep3;
285 };
286
287 static inline size_t INIT get_pos(struct writer *wr)
288 {
289         return
290                 wr->global_pos + wr->buffer_pos;
291 }
292
293 static inline uint8_t INIT peek_old_byte(struct writer *wr,
294                                                 uint32_t offs)
295 {
296         if (!wr->flush) {
297                 int32_t pos;
298                 while (offs > wr->header->dict_size)
299                         offs -= wr->header->dict_size;
300                 pos = wr->buffer_pos - offs;
301                 return wr->buffer[pos];
302         } else {
303                 uint32_t pos = wr->buffer_pos - offs;
304                 while (pos >= wr->header->dict_size)
305                         pos += wr->header->dict_size;
306                 return wr->buffer[pos];
307         }
308
309 }
310
311 static inline void INIT write_byte(struct writer *wr, uint8_t byte)
312 {
313         wr->buffer[wr->buffer_pos++] = wr->previous_byte = byte;
314         if (wr->flush && wr->buffer_pos == wr->header->dict_size) {
315                 wr->buffer_pos = 0;
316                 wr->global_pos += wr->header->dict_size;
317                 wr->flush((char *)wr->buffer, wr->header->dict_size);
318         }
319 }
320
321
322 static inline void INIT copy_byte(struct writer *wr, uint32_t offs)
323 {
324         write_byte(wr, peek_old_byte(wr, offs));
325 }
326
327 static inline void INIT copy_bytes(struct writer *wr,
328                                          uint32_t rep0, int len)
329 {
330         do {
331                 copy_byte(wr, rep0);
332                 len--;
333         } while (len != 0 && wr->buffer_pos < wr->header->dst_size);
334 }
335
336 static inline void INIT process_bit0(struct writer *wr, struct rc *rc,
337                                      struct cstate *cst, uint16_t *p,
338                                      int pos_state, uint16_t *prob,
339                                      int lc, uint32_t literal_pos_mask) {
340         int mi = 1;
341         rc_update_bit_0(rc, prob);
342         prob = (p + LZMA_LITERAL +
343                 (LZMA_LIT_SIZE
344                  * (((get_pos(wr) & literal_pos_mask) << lc)
345                     + (wr->previous_byte >> (8 - lc))))
346                 );
347
348         if (cst->state >= LZMA_NUM_LIT_STATES) {
349                 int match_byte = peek_old_byte(wr, cst->rep0);
350                 do {
351                         int bit;
352                         uint16_t *prob_lit;
353
354                         match_byte <<= 1;
355                         bit = match_byte & 0x100;
356                         prob_lit = prob + 0x100 + bit + mi;
357                         if (rc_get_bit(rc, prob_lit, &mi)) {
358                                 if (!bit)
359                                         break;
360                         } else {
361                                 if (bit)
362                                         break;
363                         }
364                 } while (mi < 0x100);
365         }
366         while (mi < 0x100) {
367                 uint16_t *prob_lit = prob + mi;
368                 rc_get_bit(rc, prob_lit, &mi);
369         }
370         write_byte(wr, mi);
371         if (cst->state < 4)
372                 cst->state = 0;
373         else if (cst->state < 10)
374                 cst->state -= 3;
375         else
376                 cst->state -= 6;
377 }
378
379 static inline void INIT process_bit1(struct writer *wr, struct rc *rc,
380                                             struct cstate *cst, uint16_t *p,
381                                             int pos_state, uint16_t *prob) {
382   int offset;
383         uint16_t *prob_len;
384         int num_bits;
385         int len;
386
387         rc_update_bit_1(rc, prob);
388         prob = p + LZMA_IS_REP + cst->state;
389         if (rc_is_bit_0(rc, prob)) {
390                 rc_update_bit_0(rc, prob);
391                 cst->rep3 = cst->rep2;
392                 cst->rep2 = cst->rep1;
393                 cst->rep1 = cst->rep0;
394                 cst->state = cst->state < LZMA_NUM_LIT_STATES ? 0 : 3;
395                 prob = p + LZMA_LEN_CODER;
396         } else {
397                 rc_update_bit_1(rc, prob);
398                 prob = p + LZMA_IS_REP_G0 + cst->state;
399                 if (rc_is_bit_0(rc, prob)) {
400                         rc_update_bit_0(rc, prob);
401                         prob = (p + LZMA_IS_REP_0_LONG
402                                 + (cst->state <<
403                                    LZMA_NUM_POS_BITS_MAX) +
404                                 pos_state);
405                         if (rc_is_bit_0(rc, prob)) {
406                                 rc_update_bit_0(rc, prob);
407
408                                 cst->state = cst->state < LZMA_NUM_LIT_STATES ?
409                                         9 : 11;
410                                 copy_byte(wr, cst->rep0);
411                                 return;
412                         } else {
413                                 rc_update_bit_1(rc, prob);
414                         }
415                 } else {
416                         uint32_t distance;
417
418                         rc_update_bit_1(rc, prob);
419                         prob = p + LZMA_IS_REP_G1 + cst->state;
420                         if (rc_is_bit_0(rc, prob)) {
421                                 rc_update_bit_0(rc, prob);
422                                 distance = cst->rep1;
423                         } else {
424                                 rc_update_bit_1(rc, prob);
425                                 prob = p + LZMA_IS_REP_G2 + cst->state;
426                                 if (rc_is_bit_0(rc, prob)) {
427                                         rc_update_bit_0(rc, prob);
428                                         distance = cst->rep2;
429                                 } else {
430                                         rc_update_bit_1(rc, prob);
431                                         distance = cst->rep3;
432                                         cst->rep3 = cst->rep2;
433                                 }
434                                 cst->rep2 = cst->rep1;
435                         }
436                         cst->rep1 = cst->rep0;
437                         cst->rep0 = distance;
438                 }
439                 cst->state = cst->state < LZMA_NUM_LIT_STATES ? 8 : 11;
440                 prob = p + LZMA_REP_LEN_CODER;
441         }
442
443         prob_len = prob + LZMA_LEN_CHOICE;
444         if (rc_is_bit_0(rc, prob_len)) {
445                 rc_update_bit_0(rc, prob_len);
446                 prob_len = (prob + LZMA_LEN_LOW
447                             + (pos_state <<
448                                LZMA_LEN_NUM_LOW_BITS));
449                 offset = 0;
450                 num_bits = LZMA_LEN_NUM_LOW_BITS;
451         } else {
452                 rc_update_bit_1(rc, prob_len);
453                 prob_len = prob + LZMA_LEN_CHOICE_2;
454                 if (rc_is_bit_0(rc, prob_len)) {
455                         rc_update_bit_0(rc, prob_len);
456                         prob_len = (prob + LZMA_LEN_MID
457                                     + (pos_state <<
458                                        LZMA_LEN_NUM_MID_BITS));
459                         offset = 1 << LZMA_LEN_NUM_LOW_BITS;
460                         num_bits = LZMA_LEN_NUM_MID_BITS;
461                 } else {
462                         rc_update_bit_1(rc, prob_len);
463                         prob_len = prob + LZMA_LEN_HIGH;
464                         offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
465                                   + (1 << LZMA_LEN_NUM_MID_BITS));
466                         num_bits = LZMA_LEN_NUM_HIGH_BITS;
467                 }
468         }
469
470         rc_bit_tree_decode(rc, prob_len, num_bits, &len);
471         len += offset;
472
473         if (cst->state < 4) {
474                 int pos_slot;
475
476                 cst->state += LZMA_NUM_LIT_STATES;
477                 prob =
478                         p + LZMA_POS_SLOT +
479                         ((len <
480                           LZMA_NUM_LEN_TO_POS_STATES ? len :
481                           LZMA_NUM_LEN_TO_POS_STATES - 1)
482                          << LZMA_NUM_POS_SLOT_BITS);
483                 rc_bit_tree_decode(rc, prob,
484                                    LZMA_NUM_POS_SLOT_BITS,
485                                    &pos_slot);
486                 if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
487                         int i, mi;
488                         num_bits = (pos_slot >> 1) - 1;
489                         cst->rep0 = 2 | (pos_slot & 1);
490                         if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
491                                 cst->rep0 <<= num_bits;
492                                 prob = p + LZMA_SPEC_POS +
493                                         cst->rep0 - pos_slot - 1;
494                         } else {
495                                 num_bits -= LZMA_NUM_ALIGN_BITS;
496                                 while (num_bits--)
497                                         cst->rep0 = (cst->rep0 << 1) |
498                                                 rc_direct_bit(rc);
499                                 prob = p + LZMA_ALIGN;
500                                 cst->rep0 <<= LZMA_NUM_ALIGN_BITS;
501                                 num_bits = LZMA_NUM_ALIGN_BITS;
502                         }
503                         i = 1;
504                         mi = 1;
505                         while (num_bits--) {
506                                 if (rc_get_bit(rc, prob + mi, &mi))
507                                         cst->rep0 |= i;
508                                 i <<= 1;
509                         }
510                 } else
511                         cst->rep0 = pos_slot;
512                 if (++(cst->rep0) == 0)
513                         return;
514         }
515
516         len += LZMA_MATCH_MIN_LEN;
517
518         copy_bytes(wr, cst->rep0, len);
519 }
520
521
522
523 STATIC inline int INIT unlzma(unsigned char *buf, int in_len,
524                               int(*fill)(void*, unsigned int),
525                               int(*flush)(void*, unsigned int),
526                               unsigned char *output,
527                               int *posp,
528                               void(*error_fn)(char *x)
529         )
530 {
531         struct lzma_header header;
532         int lc, pb, lp;
533         uint32_t pos_state_mask;
534         uint32_t literal_pos_mask;
535         uint16_t *p;
536         int num_probs;
537         struct rc rc;
538         int i, mi;
539         struct writer wr;
540         struct cstate cst;
541         unsigned char *inbuf;
542         int ret = -1;
543
544         set_error_fn(error_fn);
545         if (!flush)
546                 in_len -= 4; /* Uncompressed size hack active in pre-boot
547                                 environment */
548         if (buf)
549                 inbuf = buf;
550         else
551                 inbuf = malloc(LZMA_IOBUF_SIZE);
552         if (!inbuf) {
553                 error("Could not allocate input bufer");
554                 goto exit_0;
555         }
556
557         cst.state = 0;
558         cst.rep0 = cst.rep1 = cst.rep2 = cst.rep3 = 1;
559
560         wr.header = &header;
561         wr.flush = flush;
562         wr.global_pos = 0;
563         wr.previous_byte = 0;
564         wr.buffer_pos = 0;
565
566         rc_init(&rc, fill, inbuf, in_len);
567
568         for (i = 0; i < sizeof(header); i++) {
569                 if (rc.ptr >= rc.buffer_end)
570                         rc_read(&rc);
571                 ((unsigned char *)&header)[i] = *rc.ptr++;
572         }
573
574         if (header.pos >= (9 * 5 * 5))
575                 error("bad header");
576
577         mi = 0;
578         lc = header.pos;
579         while (lc >= 9) {
580                 mi++;
581                 lc -= 9;
582         }
583         pb = 0;
584         lp = mi;
585         while (lp >= 5) {
586                 pb++;
587                 lp -= 5;
588         }
589         pos_state_mask = (1 << pb) - 1;
590         literal_pos_mask = (1 << lp) - 1;
591
592         ENDIAN_CONVERT(header.dict_size);
593         ENDIAN_CONVERT(header.dst_size);
594
595         if (header.dict_size == 0)
596                 header.dict_size = 1;
597
598         if (output)
599                 wr.buffer = output;
600         else {
601                 wr.bufsize = MIN(header.dst_size, header.dict_size);
602                 wr.buffer = large_malloc(wr.bufsize);
603         }
604         if (wr.buffer == NULL)
605                 goto exit_1;
606
607         num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
608         p = (uint16_t *) large_malloc(num_probs * sizeof(*p));
609         if (p == 0)
610                 goto exit_2;
611         num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
612         for (i = 0; i < num_probs; i++)
613                 p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
614
615         rc_init_code(&rc);
616
617         while (get_pos(&wr) < header.dst_size) {
618                 int pos_state = get_pos(&wr) & pos_state_mask;
619                 uint16_t *prob = p + LZMA_IS_MATCH +
620                         (cst.state << LZMA_NUM_POS_BITS_MAX) + pos_state;
621                 if (rc_is_bit_0(&rc, prob))
622                         process_bit0(&wr, &rc, &cst, p, pos_state, prob,
623                                      lc, literal_pos_mask);
624                 else {
625                         process_bit1(&wr, &rc, &cst, p, pos_state, prob);
626                         if (cst.rep0 == 0)
627                                 break;
628                 }
629         }
630
631         if (posp)
632                 *posp = rc.ptr-rc.buffer;
633         if (wr.flush)
634                 wr.flush(wr.buffer, wr.buffer_pos);
635         ret = 0;
636         large_free(p);
637 exit_2:
638         if (!output)
639                 large_free(wr.buffer);
640 exit_1:
641         if (!buf)
642                 free(inbuf);
643 exit_0:
644         return ret;
645 }
646
647 #define decompress unlzma