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bashi@chromium.orgc2a93752012-05-02 00:18:22 +00001/* LzmaDec.c -- LZMA Decoder
agl@chromium.org92ae1612012-06-26 19:58:38 +000022009-09-20 : Igor Pavlov : Public domain
3in the public domain */
bashi@chromium.orgc2a93752012-05-02 00:18:22 +00004
5#include "LzmaDec.h"
6
7#include <string.h>
8
9#define kNumTopBits 24
10#define kTopValue ((UInt32)1 << kNumTopBits)
11
12#define kNumBitModelTotalBits 11
13#define kBitModelTotal (1 << kNumBitModelTotalBits)
14#define kNumMoveBits 5
15
16#define RC_INIT_SIZE 5
17
18#define NORMALIZE if (range < kTopValue) { range <<= 8; code = (code << 8) | (*buf++); }
19
20#define IF_BIT_0(p) ttt = *(p); NORMALIZE; bound = (range >> kNumBitModelTotalBits) * ttt; if (code < bound)
21#define UPDATE_0(p) range = bound; *(p) = (CLzmaProb)(ttt + ((kBitModelTotal - ttt) >> kNumMoveBits));
22#define UPDATE_1(p) range -= bound; code -= bound; *(p) = (CLzmaProb)(ttt - (ttt >> kNumMoveBits));
23#define GET_BIT2(p, i, A0, A1) IF_BIT_0(p) \
24 { UPDATE_0(p); i = (i + i); A0; } else \
25 { UPDATE_1(p); i = (i + i) + 1; A1; }
26#define GET_BIT(p, i) GET_BIT2(p, i, ; , ;)
27
28#define TREE_GET_BIT(probs, i) { GET_BIT((probs + i), i); }
29#define TREE_DECODE(probs, limit, i) \
30 { i = 1; do { TREE_GET_BIT(probs, i); } while (i < limit); i -= limit; }
31
32/* #define _LZMA_SIZE_OPT */
33
34#ifdef _LZMA_SIZE_OPT
35#define TREE_6_DECODE(probs, i) TREE_DECODE(probs, (1 << 6), i)
36#else
37#define TREE_6_DECODE(probs, i) \
38 { i = 1; \
39 TREE_GET_BIT(probs, i); \
40 TREE_GET_BIT(probs, i); \
41 TREE_GET_BIT(probs, i); \
42 TREE_GET_BIT(probs, i); \
43 TREE_GET_BIT(probs, i); \
44 TREE_GET_BIT(probs, i); \
45 i -= 0x40; }
46#endif
47
48#define NORMALIZE_CHECK if (range < kTopValue) { if (buf >= bufLimit) return DUMMY_ERROR; range <<= 8; code = (code << 8) | (*buf++); }
49
50#define IF_BIT_0_CHECK(p) ttt = *(p); NORMALIZE_CHECK; bound = (range >> kNumBitModelTotalBits) * ttt; if (code < bound)
51#define UPDATE_0_CHECK range = bound;
52#define UPDATE_1_CHECK range -= bound; code -= bound;
53#define GET_BIT2_CHECK(p, i, A0, A1) IF_BIT_0_CHECK(p) \
54 { UPDATE_0_CHECK; i = (i + i); A0; } else \
55 { UPDATE_1_CHECK; i = (i + i) + 1; A1; }
56#define GET_BIT_CHECK(p, i) GET_BIT2_CHECK(p, i, ; , ;)
57#define TREE_DECODE_CHECK(probs, limit, i) \
58 { i = 1; do { GET_BIT_CHECK(probs + i, i) } while (i < limit); i -= limit; }
59
60
61#define kNumPosBitsMax 4
62#define kNumPosStatesMax (1 << kNumPosBitsMax)
63
64#define kLenNumLowBits 3
65#define kLenNumLowSymbols (1 << kLenNumLowBits)
66#define kLenNumMidBits 3
67#define kLenNumMidSymbols (1 << kLenNumMidBits)
68#define kLenNumHighBits 8
69#define kLenNumHighSymbols (1 << kLenNumHighBits)
70
71#define LenChoice 0
72#define LenChoice2 (LenChoice + 1)
73#define LenLow (LenChoice2 + 1)
74#define LenMid (LenLow + (kNumPosStatesMax << kLenNumLowBits))
75#define LenHigh (LenMid + (kNumPosStatesMax << kLenNumMidBits))
76#define kNumLenProbs (LenHigh + kLenNumHighSymbols)
77
78
79#define kNumStates 12
80#define kNumLitStates 7
81
82#define kStartPosModelIndex 4
83#define kEndPosModelIndex 14
84#define kNumFullDistances (1 << (kEndPosModelIndex >> 1))
85
86#define kNumPosSlotBits 6
87#define kNumLenToPosStates 4
88
89#define kNumAlignBits 4
90#define kAlignTableSize (1 << kNumAlignBits)
91
92#define kMatchMinLen 2
93#define kMatchSpecLenStart (kMatchMinLen + kLenNumLowSymbols + kLenNumMidSymbols + kLenNumHighSymbols)
94
95#define IsMatch 0
96#define IsRep (IsMatch + (kNumStates << kNumPosBitsMax))
97#define IsRepG0 (IsRep + kNumStates)
98#define IsRepG1 (IsRepG0 + kNumStates)
99#define IsRepG2 (IsRepG1 + kNumStates)
100#define IsRep0Long (IsRepG2 + kNumStates)
101#define PosSlot (IsRep0Long + (kNumStates << kNumPosBitsMax))
102#define SpecPos (PosSlot + (kNumLenToPosStates << kNumPosSlotBits))
103#define Align (SpecPos + kNumFullDistances - kEndPosModelIndex)
104#define LenCoder (Align + kAlignTableSize)
105#define RepLenCoder (LenCoder + kNumLenProbs)
106#define Literal (RepLenCoder + kNumLenProbs)
107
108#define LZMA_BASE_SIZE 1846
109#define LZMA_LIT_SIZE 768
110
111#define LzmaProps_GetNumProbs(p) ((UInt32)LZMA_BASE_SIZE + (LZMA_LIT_SIZE << ((p)->lc + (p)->lp)))
112
113#if Literal != LZMA_BASE_SIZE
114StopCompilingDueBUG
115#endif
116
117#define LZMA_DIC_MIN (1 << 12)
118
119/* First LZMA-symbol is always decoded.
120And it decodes new LZMA-symbols while (buf < bufLimit), but "buf" is without last normalization
121Out:
122 Result:
123 SZ_OK - OK
124 SZ_ERROR_DATA - Error
125 p->remainLen:
126 < kMatchSpecLenStart : normal remain
127 = kMatchSpecLenStart : finished
128 = kMatchSpecLenStart + 1 : Flush marker
129 = kMatchSpecLenStart + 2 : State Init Marker
130*/
131
132static int MY_FAST_CALL LzmaDec_DecodeReal(CLzmaDec *p, SizeT limit, const Byte *bufLimit)
133{
134 CLzmaProb *probs = p->probs;
135
136 unsigned state = p->state;
137 UInt32 rep0 = p->reps[0], rep1 = p->reps[1], rep2 = p->reps[2], rep3 = p->reps[3];
138 unsigned pbMask = ((unsigned)1 << (p->prop.pb)) - 1;
139 unsigned lpMask = ((unsigned)1 << (p->prop.lp)) - 1;
140 unsigned lc = p->prop.lc;
141
142 Byte *dic = p->dic;
143 SizeT dicBufSize = p->dicBufSize;
144 SizeT dicPos = p->dicPos;
145
146 UInt32 processedPos = p->processedPos;
147 UInt32 checkDicSize = p->checkDicSize;
148 unsigned len = 0;
149
150 const Byte *buf = p->buf;
151 UInt32 range = p->range;
152 UInt32 code = p->code;
153
154 do
155 {
156 CLzmaProb *prob;
157 UInt32 bound;
158 unsigned ttt;
159 unsigned posState = processedPos & pbMask;
160
161 prob = probs + IsMatch + (state << kNumPosBitsMax) + posState;
162 IF_BIT_0(prob)
163 {
164 unsigned symbol;
165 UPDATE_0(prob);
166 prob = probs + Literal;
167 if (checkDicSize != 0 || processedPos != 0)
168 prob += (LZMA_LIT_SIZE * (((processedPos & lpMask) << lc) +
169 (dic[(dicPos == 0 ? dicBufSize : dicPos) - 1] >> (8 - lc))));
170
171 if (state < kNumLitStates)
172 {
173 state -= (state < 4) ? state : 3;
174 symbol = 1;
175 do { GET_BIT(prob + symbol, symbol) } while (symbol < 0x100);
176 }
177 else
178 {
179 unsigned matchByte = p->dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)];
180 unsigned offs = 0x100;
181 state -= (state < 10) ? 3 : 6;
182 symbol = 1;
183 do
184 {
185 unsigned bit;
186 CLzmaProb *probLit;
187 matchByte <<= 1;
188 bit = (matchByte & offs);
189 probLit = prob + offs + bit + symbol;
190 GET_BIT2(probLit, symbol, offs &= ~bit, offs &= bit)
191 }
192 while (symbol < 0x100);
193 }
194 dic[dicPos++] = (Byte)symbol;
195 processedPos++;
196 continue;
197 }
198 else
199 {
200 UPDATE_1(prob);
201 prob = probs + IsRep + state;
202 IF_BIT_0(prob)
203 {
204 UPDATE_0(prob);
205 state += kNumStates;
206 prob = probs + LenCoder;
207 }
208 else
209 {
210 UPDATE_1(prob);
211 if (checkDicSize == 0 && processedPos == 0)
212 return SZ_ERROR_DATA;
213 prob = probs + IsRepG0 + state;
214 IF_BIT_0(prob)
215 {
216 UPDATE_0(prob);
217 prob = probs + IsRep0Long + (state << kNumPosBitsMax) + posState;
218 IF_BIT_0(prob)
219 {
220 UPDATE_0(prob);
221 dic[dicPos] = dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)];
222 dicPos++;
223 processedPos++;
224 state = state < kNumLitStates ? 9 : 11;
225 continue;
226 }
227 UPDATE_1(prob);
228 }
229 else
230 {
231 UInt32 distance;
232 UPDATE_1(prob);
233 prob = probs + IsRepG1 + state;
234 IF_BIT_0(prob)
235 {
236 UPDATE_0(prob);
237 distance = rep1;
238 }
239 else
240 {
241 UPDATE_1(prob);
242 prob = probs + IsRepG2 + state;
243 IF_BIT_0(prob)
244 {
245 UPDATE_0(prob);
246 distance = rep2;
247 }
248 else
249 {
250 UPDATE_1(prob);
251 distance = rep3;
252 rep3 = rep2;
253 }
254 rep2 = rep1;
255 }
256 rep1 = rep0;
257 rep0 = distance;
258 }
259 state = state < kNumLitStates ? 8 : 11;
260 prob = probs + RepLenCoder;
261 }
262 {
263 unsigned limit, offset;
264 CLzmaProb *probLen = prob + LenChoice;
265 IF_BIT_0(probLen)
266 {
267 UPDATE_0(probLen);
268 probLen = prob + LenLow + (posState << kLenNumLowBits);
269 offset = 0;
270 limit = (1 << kLenNumLowBits);
271 }
272 else
273 {
274 UPDATE_1(probLen);
275 probLen = prob + LenChoice2;
276 IF_BIT_0(probLen)
277 {
278 UPDATE_0(probLen);
279 probLen = prob + LenMid + (posState << kLenNumMidBits);
280 offset = kLenNumLowSymbols;
281 limit = (1 << kLenNumMidBits);
282 }
283 else
284 {
285 UPDATE_1(probLen);
286 probLen = prob + LenHigh;
287 offset = kLenNumLowSymbols + kLenNumMidSymbols;
288 limit = (1 << kLenNumHighBits);
289 }
290 }
291 TREE_DECODE(probLen, limit, len);
292 len += offset;
293 }
294
295 if (state >= kNumStates)
296 {
297 UInt32 distance;
298 prob = probs + PosSlot +
299 ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) << kNumPosSlotBits);
300 TREE_6_DECODE(prob, distance);
301 if (distance >= kStartPosModelIndex)
302 {
303 unsigned posSlot = (unsigned)distance;
304 int numDirectBits = (int)(((distance >> 1) - 1));
305 distance = (2 | (distance & 1));
306 if (posSlot < kEndPosModelIndex)
307 {
308 distance <<= numDirectBits;
309 prob = probs + SpecPos + distance - posSlot - 1;
310 {
311 UInt32 mask = 1;
312 unsigned i = 1;
313 do
314 {
315 GET_BIT2(prob + i, i, ; , distance |= mask);
316 mask <<= 1;
317 }
318 while (--numDirectBits != 0);
319 }
320 }
321 else
322 {
323 numDirectBits -= kNumAlignBits;
324 do
325 {
326 NORMALIZE
327 range >>= 1;
328
329 {
330 UInt32 t;
331 code -= range;
332 t = (0 - ((UInt32)code >> 31)); /* (UInt32)((Int32)code >> 31) */
333 distance = (distance << 1) + (t + 1);
334 code += range & t;
335 }
336 /*
337 distance <<= 1;
338 if (code >= range)
339 {
340 code -= range;
341 distance |= 1;
342 }
343 */
344 }
345 while (--numDirectBits != 0);
346 prob = probs + Align;
347 distance <<= kNumAlignBits;
348 {
349 unsigned i = 1;
350 GET_BIT2(prob + i, i, ; , distance |= 1);
351 GET_BIT2(prob + i, i, ; , distance |= 2);
352 GET_BIT2(prob + i, i, ; , distance |= 4);
353 GET_BIT2(prob + i, i, ; , distance |= 8);
354 }
355 if (distance == (UInt32)0xFFFFFFFF)
356 {
357 len += kMatchSpecLenStart;
358 state -= kNumStates;
359 break;
360 }
361 }
362 }
363 rep3 = rep2;
364 rep2 = rep1;
365 rep1 = rep0;
366 rep0 = distance + 1;
367 if (checkDicSize == 0)
368 {
369 if (distance >= processedPos)
370 return SZ_ERROR_DATA;
371 }
372 else if (distance >= checkDicSize)
373 return SZ_ERROR_DATA;
374 state = (state < kNumStates + kNumLitStates) ? kNumLitStates : kNumLitStates + 3;
375 }
376
377 len += kMatchMinLen;
378
379 if (limit == dicPos)
380 return SZ_ERROR_DATA;
381 {
382 SizeT rem = limit - dicPos;
383 unsigned curLen = ((rem < len) ? (unsigned)rem : len);
384 SizeT pos = (dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0);
385
386 processedPos += curLen;
387
388 len -= curLen;
389 if (pos + curLen <= dicBufSize)
390 {
391 Byte *dest = dic + dicPos;
392 ptrdiff_t src = (ptrdiff_t)pos - (ptrdiff_t)dicPos;
393 const Byte *lim = dest + curLen;
394 dicPos += curLen;
395 do
396 *(dest) = (Byte)*(dest + src);
397 while (++dest != lim);
398 }
399 else
400 {
401 do
402 {
403 dic[dicPos++] = dic[pos];
404 if (++pos == dicBufSize)
405 pos = 0;
406 }
407 while (--curLen != 0);
408 }
409 }
410 }
411 }
412 while (dicPos < limit && buf < bufLimit);
413 NORMALIZE;
414 p->buf = buf;
415 p->range = range;
416 p->code = code;
417 p->remainLen = len;
418 p->dicPos = dicPos;
419 p->processedPos = processedPos;
420 p->reps[0] = rep0;
421 p->reps[1] = rep1;
422 p->reps[2] = rep2;
423 p->reps[3] = rep3;
424 p->state = state;
425
426 return SZ_OK;
427}
428
429static void MY_FAST_CALL LzmaDec_WriteRem(CLzmaDec *p, SizeT limit)
430{
431 if (p->remainLen != 0 && p->remainLen < kMatchSpecLenStart)
432 {
433 Byte *dic = p->dic;
434 SizeT dicPos = p->dicPos;
435 SizeT dicBufSize = p->dicBufSize;
436 unsigned len = p->remainLen;
437 UInt32 rep0 = p->reps[0];
438 if (limit - dicPos < len)
439 len = (unsigned)(limit - dicPos);
440
441 if (p->checkDicSize == 0 && p->prop.dicSize - p->processedPos <= len)
442 p->checkDicSize = p->prop.dicSize;
443
444 p->processedPos += len;
445 p->remainLen -= len;
446 while (len-- != 0)
447 {
448 dic[dicPos] = dic[(dicPos - rep0) + ((dicPos < rep0) ? dicBufSize : 0)];
449 dicPos++;
450 }
451 p->dicPos = dicPos;
452 }
453}
454
455static int MY_FAST_CALL LzmaDec_DecodeReal2(CLzmaDec *p, SizeT limit, const Byte *bufLimit)
456{
457 do
458 {
459 SizeT limit2 = limit;
460 if (p->checkDicSize == 0)
461 {
462 UInt32 rem = p->prop.dicSize - p->processedPos;
463 if (limit - p->dicPos > rem)
464 limit2 = p->dicPos + rem;
465 }
466 RINOK(LzmaDec_DecodeReal(p, limit2, bufLimit));
467 if (p->processedPos >= p->prop.dicSize)
468 p->checkDicSize = p->prop.dicSize;
469 LzmaDec_WriteRem(p, limit);
470 }
471 while (p->dicPos < limit && p->buf < bufLimit && p->remainLen < kMatchSpecLenStart);
472
473 if (p->remainLen > kMatchSpecLenStart)
474 {
475 p->remainLen = kMatchSpecLenStart;
476 }
477 return 0;
478}
479
480typedef enum
481{
482 DUMMY_ERROR, /* unexpected end of input stream */
483 DUMMY_LIT,
484 DUMMY_MATCH,
485 DUMMY_REP
486} ELzmaDummy;
487
488static ELzmaDummy LzmaDec_TryDummy(const CLzmaDec *p, const Byte *buf, SizeT inSize)
489{
490 UInt32 range = p->range;
491 UInt32 code = p->code;
492 const Byte *bufLimit = buf + inSize;
493 CLzmaProb *probs = p->probs;
494 unsigned state = p->state;
495 ELzmaDummy res;
496
497 {
498 CLzmaProb *prob;
499 UInt32 bound;
500 unsigned ttt;
501 unsigned posState = (p->processedPos) & ((1 << p->prop.pb) - 1);
502
503 prob = probs + IsMatch + (state << kNumPosBitsMax) + posState;
504 IF_BIT_0_CHECK(prob)
505 {
506 UPDATE_0_CHECK
507
508 /* if (bufLimit - buf >= 7) return DUMMY_LIT; */
509
510 prob = probs + Literal;
511 if (p->checkDicSize != 0 || p->processedPos != 0)
512 prob += (LZMA_LIT_SIZE *
513 ((((p->processedPos) & ((1 << (p->prop.lp)) - 1)) << p->prop.lc) +
514 (p->dic[(p->dicPos == 0 ? p->dicBufSize : p->dicPos) - 1] >> (8 - p->prop.lc))));
515
516 if (state < kNumLitStates)
517 {
518 unsigned symbol = 1;
519 do { GET_BIT_CHECK(prob + symbol, symbol) } while (symbol < 0x100);
520 }
521 else
522 {
523 unsigned matchByte = p->dic[p->dicPos - p->reps[0] +
524 ((p->dicPos < p->reps[0]) ? p->dicBufSize : 0)];
525 unsigned offs = 0x100;
526 unsigned symbol = 1;
527 do
528 {
529 unsigned bit;
530 CLzmaProb *probLit;
531 matchByte <<= 1;
532 bit = (matchByte & offs);
533 probLit = prob + offs + bit + symbol;
534 GET_BIT2_CHECK(probLit, symbol, offs &= ~bit, offs &= bit)
535 }
536 while (symbol < 0x100);
537 }
538 res = DUMMY_LIT;
539 }
540 else
541 {
542 unsigned len;
543 UPDATE_1_CHECK;
544
545 prob = probs + IsRep + state;
546 IF_BIT_0_CHECK(prob)
547 {
548 UPDATE_0_CHECK;
549 state = 0;
550 prob = probs + LenCoder;
551 res = DUMMY_MATCH;
552 }
553 else
554 {
555 UPDATE_1_CHECK;
556 res = DUMMY_REP;
557 prob = probs + IsRepG0 + state;
558 IF_BIT_0_CHECK(prob)
559 {
560 UPDATE_0_CHECK;
561 prob = probs + IsRep0Long + (state << kNumPosBitsMax) + posState;
562 IF_BIT_0_CHECK(prob)
563 {
564 UPDATE_0_CHECK;
565 NORMALIZE_CHECK;
566 return DUMMY_REP;
567 }
568 else
569 {
570 UPDATE_1_CHECK;
571 }
572 }
573 else
574 {
575 UPDATE_1_CHECK;
576 prob = probs + IsRepG1 + state;
577 IF_BIT_0_CHECK(prob)
578 {
579 UPDATE_0_CHECK;
580 }
581 else
582 {
583 UPDATE_1_CHECK;
584 prob = probs + IsRepG2 + state;
585 IF_BIT_0_CHECK(prob)
586 {
587 UPDATE_0_CHECK;
588 }
589 else
590 {
591 UPDATE_1_CHECK;
592 }
593 }
594 }
595 state = kNumStates;
596 prob = probs + RepLenCoder;
597 }
598 {
599 unsigned limit, offset;
600 CLzmaProb *probLen = prob + LenChoice;
601 IF_BIT_0_CHECK(probLen)
602 {
603 UPDATE_0_CHECK;
604 probLen = prob + LenLow + (posState << kLenNumLowBits);
605 offset = 0;
606 limit = 1 << kLenNumLowBits;
607 }
608 else
609 {
610 UPDATE_1_CHECK;
611 probLen = prob + LenChoice2;
612 IF_BIT_0_CHECK(probLen)
613 {
614 UPDATE_0_CHECK;
615 probLen = prob + LenMid + (posState << kLenNumMidBits);
616 offset = kLenNumLowSymbols;
617 limit = 1 << kLenNumMidBits;
618 }
619 else
620 {
621 UPDATE_1_CHECK;
622 probLen = prob + LenHigh;
623 offset = kLenNumLowSymbols + kLenNumMidSymbols;
624 limit = 1 << kLenNumHighBits;
625 }
626 }
627 TREE_DECODE_CHECK(probLen, limit, len);
628 len += offset;
629 }
630
631 if (state < 4)
632 {
633 unsigned posSlot;
634 prob = probs + PosSlot +
635 ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) <<
636 kNumPosSlotBits);
637 TREE_DECODE_CHECK(prob, 1 << kNumPosSlotBits, posSlot);
638 if (posSlot >= kStartPosModelIndex)
639 {
640 int numDirectBits = ((posSlot >> 1) - 1);
641
642 /* if (bufLimit - buf >= 8) return DUMMY_MATCH; */
643
644 if (posSlot < kEndPosModelIndex)
645 {
646 prob = probs + SpecPos + ((2 | (posSlot & 1)) << numDirectBits) - posSlot - 1;
647 }
648 else
649 {
650 numDirectBits -= kNumAlignBits;
651 do
652 {
653 NORMALIZE_CHECK
654 range >>= 1;
655 code -= range & (((code - range) >> 31) - 1);
656 /* if (code >= range) code -= range; */
657 }
658 while (--numDirectBits != 0);
659 prob = probs + Align;
660 numDirectBits = kNumAlignBits;
661 }
662 {
663 unsigned i = 1;
664 do
665 {
666 GET_BIT_CHECK(prob + i, i);
667 }
668 while (--numDirectBits != 0);
669 }
670 }
671 }
672 }
673 }
674 NORMALIZE_CHECK;
675 return res;
676}
677
678
679static void LzmaDec_InitRc(CLzmaDec *p, const Byte *data)
680{
681 p->code = ((UInt32)data[1] << 24) | ((UInt32)data[2] << 16) | ((UInt32)data[3] << 8) | ((UInt32)data[4]);
682 p->range = 0xFFFFFFFF;
683 p->needFlush = 0;
684}
685
686void LzmaDec_InitDicAndState(CLzmaDec *p, Bool initDic, Bool initState)
687{
688 p->needFlush = 1;
689 p->remainLen = 0;
690 p->tempBufSize = 0;
691
692 if (initDic)
693 {
694 p->processedPos = 0;
695 p->checkDicSize = 0;
696 p->needInitState = 1;
697 }
698 if (initState)
699 p->needInitState = 1;
700}
701
702void LzmaDec_Init(CLzmaDec *p)
703{
704 p->dicPos = 0;
705 LzmaDec_InitDicAndState(p, True, True);
706}
707
708static void LzmaDec_InitStateReal(CLzmaDec *p)
709{
710 UInt32 numProbs = Literal + ((UInt32)LZMA_LIT_SIZE << (p->prop.lc + p->prop.lp));
711 UInt32 i;
712 CLzmaProb *probs = p->probs;
713 for (i = 0; i < numProbs; i++)
714 probs[i] = kBitModelTotal >> 1;
715 p->reps[0] = p->reps[1] = p->reps[2] = p->reps[3] = 1;
716 p->state = 0;
717 p->needInitState = 0;
718}
719
720SRes LzmaDec_DecodeToDic(CLzmaDec *p, SizeT dicLimit, const Byte *src, SizeT *srcLen,
721 ELzmaFinishMode finishMode, ELzmaStatus *status)
722{
723 SizeT inSize = *srcLen;
724 (*srcLen) = 0;
725 LzmaDec_WriteRem(p, dicLimit);
726
727 *status = LZMA_STATUS_NOT_SPECIFIED;
728
729 while (p->remainLen != kMatchSpecLenStart)
730 {
731 int checkEndMarkNow;
732
733 if (p->needFlush != 0)
734 {
735 for (; inSize > 0 && p->tempBufSize < RC_INIT_SIZE; (*srcLen)++, inSize--)
736 p->tempBuf[p->tempBufSize++] = *src++;
737 if (p->tempBufSize < RC_INIT_SIZE)
738 {
739 *status = LZMA_STATUS_NEEDS_MORE_INPUT;
740 return SZ_OK;
741 }
742 if (p->tempBuf[0] != 0)
743 return SZ_ERROR_DATA;
744
745 LzmaDec_InitRc(p, p->tempBuf);
746 p->tempBufSize = 0;
747 }
748
749 checkEndMarkNow = 0;
750 if (p->dicPos >= dicLimit)
751 {
752 if (p->remainLen == 0 && p->code == 0)
753 {
754 *status = LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK;
755 return SZ_OK;
756 }
757 if (finishMode == LZMA_FINISH_ANY)
758 {
759 *status = LZMA_STATUS_NOT_FINISHED;
760 return SZ_OK;
761 }
762 if (p->remainLen != 0)
763 {
764 *status = LZMA_STATUS_NOT_FINISHED;
765 return SZ_ERROR_DATA;
766 }
767 checkEndMarkNow = 1;
768 }
769
770 if (p->needInitState)
771 LzmaDec_InitStateReal(p);
772
773 if (p->tempBufSize == 0)
774 {
775 SizeT processed;
776 const Byte *bufLimit;
777 if (inSize < LZMA_REQUIRED_INPUT_MAX || checkEndMarkNow)
778 {
779 int dummyRes = LzmaDec_TryDummy(p, src, inSize);
780 if (dummyRes == DUMMY_ERROR)
781 {
782 memcpy(p->tempBuf, src, inSize);
783 p->tempBufSize = (unsigned)inSize;
784 (*srcLen) += inSize;
785 *status = LZMA_STATUS_NEEDS_MORE_INPUT;
786 return SZ_OK;
787 }
788 if (checkEndMarkNow && dummyRes != DUMMY_MATCH)
789 {
790 *status = LZMA_STATUS_NOT_FINISHED;
791 return SZ_ERROR_DATA;
792 }
793 bufLimit = src;
794 }
795 else
796 bufLimit = src + inSize - LZMA_REQUIRED_INPUT_MAX;
797 p->buf = src;
798 if (LzmaDec_DecodeReal2(p, dicLimit, bufLimit) != 0)
799 return SZ_ERROR_DATA;
800 processed = (SizeT)(p->buf - src);
801 (*srcLen) += processed;
802 src += processed;
803 inSize -= processed;
804 }
805 else
806 {
807 unsigned rem = p->tempBufSize, lookAhead = 0;
808 while (rem < LZMA_REQUIRED_INPUT_MAX && lookAhead < inSize)
809 p->tempBuf[rem++] = src[lookAhead++];
810 p->tempBufSize = rem;
811 if (rem < LZMA_REQUIRED_INPUT_MAX || checkEndMarkNow)
812 {
813 int dummyRes = LzmaDec_TryDummy(p, p->tempBuf, rem);
814 if (dummyRes == DUMMY_ERROR)
815 {
816 (*srcLen) += lookAhead;
817 *status = LZMA_STATUS_NEEDS_MORE_INPUT;
818 return SZ_OK;
819 }
820 if (checkEndMarkNow && dummyRes != DUMMY_MATCH)
821 {
822 *status = LZMA_STATUS_NOT_FINISHED;
823 return SZ_ERROR_DATA;
824 }
825 }
826 p->buf = p->tempBuf;
827 if (LzmaDec_DecodeReal2(p, dicLimit, p->buf) != 0)
828 return SZ_ERROR_DATA;
829 lookAhead -= (rem - (unsigned)(p->buf - p->tempBuf));
830 (*srcLen) += lookAhead;
831 src += lookAhead;
832 inSize -= lookAhead;
833 p->tempBufSize = 0;
834 }
835 }
836 if (p->code == 0)
837 *status = LZMA_STATUS_FINISHED_WITH_MARK;
838 return (p->code == 0) ? SZ_OK : SZ_ERROR_DATA;
839}
840
841SRes LzmaDec_DecodeToBuf(CLzmaDec *p, Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen, ELzmaFinishMode finishMode, ELzmaStatus *status)
842{
843 SizeT outSize = *destLen;
844 SizeT inSize = *srcLen;
845 *srcLen = *destLen = 0;
846 for (;;)
847 {
848 SizeT inSizeCur = inSize, outSizeCur, dicPos;
849 ELzmaFinishMode curFinishMode;
850 SRes res;
851 if (p->dicPos == p->dicBufSize)
852 p->dicPos = 0;
853 dicPos = p->dicPos;
854 if (outSize > p->dicBufSize - dicPos)
855 {
856 outSizeCur = p->dicBufSize;
857 curFinishMode = LZMA_FINISH_ANY;
858 }
859 else
860 {
861 outSizeCur = dicPos + outSize;
862 curFinishMode = finishMode;
863 }
864
865 res = LzmaDec_DecodeToDic(p, outSizeCur, src, &inSizeCur, curFinishMode, status);
866 src += inSizeCur;
867 inSize -= inSizeCur;
868 *srcLen += inSizeCur;
869 outSizeCur = p->dicPos - dicPos;
870 memcpy(dest, p->dic + dicPos, outSizeCur);
871 dest += outSizeCur;
872 outSize -= outSizeCur;
873 *destLen += outSizeCur;
874 if (res != 0)
875 return res;
876 if (outSizeCur == 0 || outSize == 0)
877 return SZ_OK;
878 }
879}
880
881void LzmaDec_FreeProbs(CLzmaDec *p, ISzAlloc *alloc)
882{
883 alloc->Free(alloc, p->probs);
884 p->probs = 0;
885}
886
887static void LzmaDec_FreeDict(CLzmaDec *p, ISzAlloc *alloc)
888{
889 alloc->Free(alloc, p->dic);
890 p->dic = 0;
891}
892
893void LzmaDec_Free(CLzmaDec *p, ISzAlloc *alloc)
894{
895 LzmaDec_FreeProbs(p, alloc);
896 LzmaDec_FreeDict(p, alloc);
897}
898
899SRes LzmaProps_Decode(CLzmaProps *p, const Byte *data, unsigned size)
900{
901 UInt32 dicSize;
902 Byte d;
903
904 if (size < LZMA_PROPS_SIZE)
905 return SZ_ERROR_UNSUPPORTED;
906 else
907 dicSize = data[1] | ((UInt32)data[2] << 8) | ((UInt32)data[3] << 16) | ((UInt32)data[4] << 24);
908
909 if (dicSize < LZMA_DIC_MIN)
910 dicSize = LZMA_DIC_MIN;
911 p->dicSize = dicSize;
912
913 d = data[0];
914 if (d >= (9 * 5 * 5))
915 return SZ_ERROR_UNSUPPORTED;
916
917 p->lc = d % 9;
918 d /= 9;
919 p->pb = d / 5;
920 p->lp = d % 5;
921
922 return SZ_OK;
923}
924
925static SRes LzmaDec_AllocateProbs2(CLzmaDec *p, const CLzmaProps *propNew, ISzAlloc *alloc)
926{
927 UInt32 numProbs = LzmaProps_GetNumProbs(propNew);
928 if (p->probs == 0 || numProbs != p->numProbs)
929 {
930 LzmaDec_FreeProbs(p, alloc);
931 p->probs = (CLzmaProb *)alloc->Alloc(alloc, numProbs * sizeof(CLzmaProb));
932 p->numProbs = numProbs;
933 if (p->probs == 0)
934 return SZ_ERROR_MEM;
935 }
936 return SZ_OK;
937}
938
939SRes LzmaDec_AllocateProbs(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc)
940{
941 CLzmaProps propNew;
942 RINOK(LzmaProps_Decode(&propNew, props, propsSize));
943 RINOK(LzmaDec_AllocateProbs2(p, &propNew, alloc));
944 p->prop = propNew;
945 return SZ_OK;
946}
947
948SRes LzmaDec_Allocate(CLzmaDec *p, const Byte *props, unsigned propsSize, ISzAlloc *alloc)
949{
950 CLzmaProps propNew;
951 SizeT dicBufSize;
952 RINOK(LzmaProps_Decode(&propNew, props, propsSize));
953 RINOK(LzmaDec_AllocateProbs2(p, &propNew, alloc));
954 dicBufSize = propNew.dicSize;
955 if (p->dic == 0 || dicBufSize != p->dicBufSize)
956 {
957 LzmaDec_FreeDict(p, alloc);
958 p->dic = (Byte *)alloc->Alloc(alloc, dicBufSize);
959 if (p->dic == 0)
960 {
961 LzmaDec_FreeProbs(p, alloc);
962 return SZ_ERROR_MEM;
963 }
964 }
965 p->dicBufSize = dicBufSize;
966 p->prop = propNew;
967 return SZ_OK;
968}
969
970SRes LzmaDecode(Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
971 const Byte *propData, unsigned propSize, ELzmaFinishMode finishMode,
972 ELzmaStatus *status, ISzAlloc *alloc)
973{
974 CLzmaDec p;
975 SRes res;
976 SizeT inSize = *srcLen;
977 SizeT outSize = *destLen;
978 *srcLen = *destLen = 0;
979 if (inSize < RC_INIT_SIZE)
980 return SZ_ERROR_INPUT_EOF;
981
982 LzmaDec_Construct(&p);
983 res = LzmaDec_AllocateProbs(&p, propData, propSize, alloc);
984 if (res != 0)
985 return res;
986 p.dic = dest;
987 p.dicBufSize = outSize;
988
989 LzmaDec_Init(&p);
990
991 *srcLen = inSize;
992 res = LzmaDec_DecodeToDic(&p, outSize, src, srcLen, finishMode, status);
993
994 if (res == SZ_OK && *status == LZMA_STATUS_NEEDS_MORE_INPUT)
995 res = SZ_ERROR_INPUT_EOF;
996
997 (*destLen) = p.dicPos;
998 LzmaDec_FreeProbs(&p, alloc);
999 return res;
1000}