5
/*-------------------------------------------------------------*/
6
/*--- Decompression machinery ---*/
7
/*--- decompress.c ---*/
8
/*-------------------------------------------------------------*/
11
This file is a part of bzip2 and/or libbzip2, a program and
12
library for lossless, block-sorting data compression.
14
Copyright (C) 1996-2002 Julian R Seward. All rights reserved.
16
Redistribution and use in source and binary forms, with or without
17
modification, are permitted provided that the following conditions
20
1. Redistributions of source code must retain the above copyright
21
notice, this list of conditions and the following disclaimer.
23
2. The origin of this software must not be misrepresented; you must
24
not claim that you wrote the original software. If you use this
25
software in a product, an acknowledgment in the product
26
documentation would be appreciated but is not required.
28
3. Altered source versions must be plainly marked as such, and must
29
not be misrepresented as being the original software.
31
4. The name of the author may not be used to endorse or promote
32
products derived from this software without specific prior written
35
THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
36
OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
37
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
38
ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
39
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
40
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
41
GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
42
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
43
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
44
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
45
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
47
Julian Seward, Cambridge, UK.
49
bzip2/libbzip2 version 1.0 of 21 March 2000
51
This program is based on (at least) the work of:
61
For more information on these sources, see the manual.
65
#include "bzlib_private.h"
68
/*---------------------------------------------------*/
70
void makeMaps_d ( DState* s )
74
for (i = 0; i < 256; i++)
76
s->seqToUnseq[s->nInUse] = i;
82
/*---------------------------------------------------*/
84
{ retVal = rrr; goto save_state_and_return; };
86
#define GET_BITS(lll,vvv,nnn) \
87
case lll: s->state = lll; \
89
if (s->bsLive >= nnn) { \
92
(s->bsLive-nnn)) & ((1 << nnn)-1); \
97
if (s->strm->avail_in == 0) RETURN(BZ_OK); \
99
= (s->bsBuff << 8) | \
101
(*((UChar*)(s->strm->next_in)))); \
103
s->strm->next_in++; \
104
s->strm->avail_in--; \
105
s->strm->total_in_lo32++; \
106
if (s->strm->total_in_lo32 == 0) \
107
s->strm->total_in_hi32++; \
110
#define GET_UCHAR(lll,uuu) \
113
#define GET_BIT(lll,uuu) \
116
/*---------------------------------------------------*/
117
#define GET_MTF_VAL(label1,label2,lval) \
119
if (groupPos == 0) { \
121
if (groupNo >= nSelectors) \
122
RETURN(BZ_DATA_ERROR); \
123
groupPos = BZ_G_SIZE; \
124
gSel = s->selector[groupNo]; \
125
gMinlen = s->minLens[gSel]; \
126
gLimit = &(s->limit[gSel][0]); \
127
gPerm = &(s->perm[gSel][0]); \
128
gBase = &(s->base[gSel][0]); \
132
GET_BITS(label1, zvec, zn); \
134
if (zn > 20 /* the longest code */) \
135
RETURN(BZ_DATA_ERROR); \
136
if (zvec <= gLimit[zn]) break; \
138
GET_BIT(label2, zj); \
139
zvec = (zvec << 1) | zj; \
141
if (zvec - gBase[zn] < 0 \
142
|| zvec - gBase[zn] >= BZ_MAX_ALPHA_SIZE) \
143
RETURN(BZ_DATA_ERROR); \
144
lval = gPerm[zvec - gBase[zn]]; \
148
/*---------------------------------------------------*/
149
Int32 BZ2_decompress ( DState* s )
153
Int32 minLen, maxLen;
154
bz_stream* strm = s->strm;
156
/* stuff that needs to be saved/restored */
182
if (s->state == BZ_X_MAGIC_1) {
183
/*initialise the save area*/
187
s->save_alphaSize = 0;
189
s->save_nSelectors = 0;
192
s->save_groupPos = 0;
194
s->save_nblockMAX = 0;
205
s->save_gLimit = NULL;
206
s->save_gBase = NULL;
207
s->save_gPerm = NULL;
210
/*restore from the save area*/
214
alphaSize = s->save_alphaSize;
215
nGroups = s->save_nGroups;
216
nSelectors = s->save_nSelectors;
218
groupNo = s->save_groupNo;
219
groupPos = s->save_groupPos;
220
nextSym = s->save_nextSym;
221
nblockMAX = s->save_nblockMAX;
222
nblock = s->save_nblock;
231
gMinlen = s->save_gMinlen;
232
gLimit = s->save_gLimit;
233
gBase = s->save_gBase;
234
gPerm = s->save_gPerm;
240
GET_UCHAR(BZ_X_MAGIC_1, uc);
241
if (uc != BZ_HDR_B) RETURN(BZ_DATA_ERROR_MAGIC);
243
GET_UCHAR(BZ_X_MAGIC_2, uc);
244
if (uc != BZ_HDR_Z) RETURN(BZ_DATA_ERROR_MAGIC);
246
GET_UCHAR(BZ_X_MAGIC_3, uc)
247
if (uc != BZ_HDR_h) RETURN(BZ_DATA_ERROR_MAGIC);
249
GET_BITS(BZ_X_MAGIC_4, s->blockSize100k, 8)
250
if (s->blockSize100k < (BZ_HDR_0 + 1) ||
251
s->blockSize100k > (BZ_HDR_0 + 9)) RETURN(BZ_DATA_ERROR_MAGIC);
252
s->blockSize100k -= BZ_HDR_0;
254
if (s->smallDecompress) {
255
s->ll16 = BZALLOC( s->blockSize100k * 100000 * sizeof(UInt16) );
257
((1 + s->blockSize100k * 100000) >> 1) * sizeof(UChar)
259
if (s->ll16 == NULL || s->ll4 == NULL) RETURN(BZ_MEM_ERROR);
261
s->tt = BZALLOC( s->blockSize100k * 100000 * sizeof(Int32) );
262
if (s->tt == NULL) RETURN(BZ_MEM_ERROR);
265
GET_UCHAR(BZ_X_BLKHDR_1, uc);
267
if (uc == 0x17) goto endhdr_2;
268
if (uc != 0x31) RETURN(BZ_DATA_ERROR);
269
GET_UCHAR(BZ_X_BLKHDR_2, uc);
270
if (uc != 0x41) RETURN(BZ_DATA_ERROR);
271
GET_UCHAR(BZ_X_BLKHDR_3, uc);
272
if (uc != 0x59) RETURN(BZ_DATA_ERROR);
273
GET_UCHAR(BZ_X_BLKHDR_4, uc);
274
if (uc != 0x26) RETURN(BZ_DATA_ERROR);
275
GET_UCHAR(BZ_X_BLKHDR_5, uc);
276
if (uc != 0x53) RETURN(BZ_DATA_ERROR);
277
GET_UCHAR(BZ_X_BLKHDR_6, uc);
278
if (uc != 0x59) RETURN(BZ_DATA_ERROR);
281
if (s->verbosity >= 2)
282
VPrintf1 ( "\n [%d: huff+mtf ", s->currBlockNo );
284
s->storedBlockCRC = 0;
285
GET_UCHAR(BZ_X_BCRC_1, uc);
286
s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
287
GET_UCHAR(BZ_X_BCRC_2, uc);
288
s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
289
GET_UCHAR(BZ_X_BCRC_3, uc);
290
s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
291
GET_UCHAR(BZ_X_BCRC_4, uc);
292
s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
294
GET_BITS(BZ_X_RANDBIT, s->blockRandomised, 1);
297
GET_UCHAR(BZ_X_ORIGPTR_1, uc);
298
s->origPtr = (s->origPtr << 8) | ((Int32)uc);
299
GET_UCHAR(BZ_X_ORIGPTR_2, uc);
300
s->origPtr = (s->origPtr << 8) | ((Int32)uc);
301
GET_UCHAR(BZ_X_ORIGPTR_3, uc);
302
s->origPtr = (s->origPtr << 8) | ((Int32)uc);
305
RETURN(BZ_DATA_ERROR);
306
if (s->origPtr > 10 + 100000*s->blockSize100k)
307
RETURN(BZ_DATA_ERROR);
309
/*--- Receive the mapping table ---*/
310
for (i = 0; i < 16; i++) {
311
GET_BIT(BZ_X_MAPPING_1, uc);
313
s->inUse16[i] = True; else
314
s->inUse16[i] = False;
317
for (i = 0; i < 256; i++) s->inUse[i] = False;
319
for (i = 0; i < 16; i++)
321
for (j = 0; j < 16; j++) {
322
GET_BIT(BZ_X_MAPPING_2, uc);
323
if (uc == 1) s->inUse[i * 16 + j] = True;
326
if (s->nInUse == 0) RETURN(BZ_DATA_ERROR);
327
alphaSize = s->nInUse+2;
329
/*--- Now the selectors ---*/
330
GET_BITS(BZ_X_SELECTOR_1, nGroups, 3);
331
if (nGroups < 2 || nGroups > 6) RETURN(BZ_DATA_ERROR);
332
GET_BITS(BZ_X_SELECTOR_2, nSelectors, 15);
333
if (nSelectors < 1) RETURN(BZ_DATA_ERROR);
334
for (i = 0; i < nSelectors; i++) {
337
GET_BIT(BZ_X_SELECTOR_3, uc);
340
if (j >= nGroups) RETURN(BZ_DATA_ERROR);
342
s->selectorMtf[i] = j;
345
/*--- Undo the MTF values for the selectors. ---*/
347
UChar pos[BZ_N_GROUPS], tmp, v;
348
for (v = 0; v < nGroups; v++) pos[v] = v;
350
for (i = 0; i < nSelectors; i++) {
351
v = s->selectorMtf[i];
353
while (v > 0) { pos[v] = pos[v-1]; v--; }
355
s->selector[i] = tmp;
359
/*--- Now the coding tables ---*/
360
for (t = 0; t < nGroups; t++) {
361
GET_BITS(BZ_X_CODING_1, curr, 5);
362
for (i = 0; i < alphaSize; i++) {
364
if (curr < 1 || curr > 20) RETURN(BZ_DATA_ERROR);
365
GET_BIT(BZ_X_CODING_2, uc);
367
GET_BIT(BZ_X_CODING_3, uc);
368
if (uc == 0) curr++; else curr--;
374
/*--- Create the Huffman decoding tables ---*/
375
for (t = 0; t < nGroups; t++) {
378
for (i = 0; i < alphaSize; i++) {
379
if (s->len[t][i] > maxLen) maxLen = s->len[t][i];
380
if (s->len[t][i] < minLen) minLen = s->len[t][i];
382
BZ2_hbCreateDecodeTables (
387
minLen, maxLen, alphaSize
389
s->minLens[t] = minLen;
392
/*--- Now the MTF values ---*/
395
nblockMAX = 100000 * s->blockSize100k;
399
for (i = 0; i <= 255; i++) s->unzftab[i] = 0;
405
for (ii = 256 / MTFL_SIZE - 1; ii >= 0; ii--) {
406
for (jj = MTFL_SIZE-1; jj >= 0; jj--) {
407
s->mtfa[kk] = (UChar)(ii * MTFL_SIZE + jj);
410
s->mtfbase[ii] = kk + 1;
413
/*-- end MTF init --*/
416
GET_MTF_VAL(BZ_X_MTF_1, BZ_X_MTF_2, nextSym);
420
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
423
if (nextSym == EOB) break;
425
if (nextSym == BZ_RUNA || nextSym == BZ_RUNB) {
430
if (nextSym == BZ_RUNA) es = es + (0+1) * N; else
431
if (nextSym == BZ_RUNB) es = es + (1+1) * N;
433
GET_MTF_VAL(BZ_X_MTF_3, BZ_X_MTF_4, nextSym);
435
while (nextSym == BZ_RUNA || nextSym == BZ_RUNB);
438
uc = s->seqToUnseq[ s->mtfa[s->mtfbase[0]] ];
439
s->unzftab[uc] += es;
441
if (s->smallDecompress)
443
if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR);
444
s->ll16[nblock] = (UInt16)uc;
450
if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR);
451
s->tt[nblock] = (UInt32)uc;
460
if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR);
462
/*-- uc = MTF ( nextSym-1 ) --*/
464
Int32 ii, jj, kk, pp, lno, off;
466
nn = (UInt32)(nextSym - 1);
468
if (nn < MTFL_SIZE) {
469
/* avoid general-case expense */
474
s->mtfa[(z) ] = s->mtfa[(z)-1];
475
s->mtfa[(z)-1] = s->mtfa[(z)-2];
476
s->mtfa[(z)-2] = s->mtfa[(z)-3];
477
s->mtfa[(z)-3] = s->mtfa[(z)-4];
481
s->mtfa[(pp+nn)] = s->mtfa[(pp+nn)-1]; nn--;
486
lno = nn / MTFL_SIZE;
487
off = nn % MTFL_SIZE;
488
pp = s->mtfbase[lno] + off;
490
while (pp > s->mtfbase[lno]) {
491
s->mtfa[pp] = s->mtfa[pp-1]; pp--;
496
s->mtfa[s->mtfbase[lno]]
497
= s->mtfa[s->mtfbase[lno-1] + MTFL_SIZE - 1];
501
s->mtfa[s->mtfbase[0]] = uc;
502
if (s->mtfbase[0] == 0) {
504
for (ii = 256 / MTFL_SIZE-1; ii >= 0; ii--) {
505
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
508
for (jj = MTFL_SIZE-1; jj >= 0; jj--) {
509
s->mtfa[kk] = s->mtfa[s->mtfbase[ii] + jj];
512
s->mtfbase[ii] = kk + 1;
517
/*-- end uc = MTF ( nextSym-1 ) --*/
519
s->unzftab[s->seqToUnseq[uc]]++;
520
if (s->smallDecompress)
521
s->ll16[nblock] = (UInt16)(s->seqToUnseq[uc]); else
522
s->tt[nblock] = (UInt32)(s->seqToUnseq[uc]);
525
GET_MTF_VAL(BZ_X_MTF_5, BZ_X_MTF_6, nextSym);
530
/* Now we know what nblock is, we can do a better sanity
533
if (s->origPtr < 0 || s->origPtr >= nblock)
534
RETURN(BZ_DATA_ERROR);
536
s->state_out_len = 0;
538
BZ_INITIALISE_CRC ( s->calculatedBlockCRC );
539
s->state = BZ_X_OUTPUT;
540
if (s->verbosity >= 2) VPrintf0 ( "rt+rld" );
542
/*-- Set up cftab to facilitate generation of T^(-1) --*/
544
for (i = 1; i <= 256; i++) s->cftab[i] = s->unzftab[i-1];
545
for (i = 1; i <= 256; i++) s->cftab[i] += s->cftab[i-1];
547
if (s->smallDecompress) {
549
/*-- Make a copy of cftab, used in generation of T --*/
550
for (i = 0; i <= 256; i++) s->cftabCopy[i] = s->cftab[i];
552
/*-- compute the T vector --*/
553
for (i = 0; i < nblock; i++) {
554
uc = (UChar)(s->ll16[i]);
555
SET_LL(i, s->cftabCopy[uc]);
559
/*-- Compute T^(-1) by pointer reversal on T --*/
563
Int32 tmp = GET_LL(j);
568
while (i != s->origPtr);
570
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
573
s->tPos = s->origPtr;
575
if (s->blockRandomised) {
577
BZ_GET_SMALL(s->k0); s->nblock_used++;
578
BZ_RAND_UPD_MASK; s->k0 ^= BZ_RAND_MASK;
580
BZ_GET_SMALL(s->k0); s->nblock_used++;
585
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
588
/*-- compute the T^(-1) vector --*/
589
for (i = 0; i < nblock; i++) {
590
uc = (UChar)(s->tt[i] & 0xff);
591
s->tt[s->cftab[uc]] |= (i << 8);
595
s->tPos = s->tt[s->origPtr] >> 8;
597
if (s->blockRandomised) {
599
BZ_GET_FAST(s->k0); s->nblock_used++;
600
BZ_RAND_UPD_MASK; s->k0 ^= BZ_RAND_MASK;
602
BZ_GET_FAST(s->k0); s->nblock_used++;
612
GET_UCHAR(BZ_X_ENDHDR_2, uc);
613
if (uc != 0x72) RETURN(BZ_DATA_ERROR);
614
GET_UCHAR(BZ_X_ENDHDR_3, uc);
615
if (uc != 0x45) RETURN(BZ_DATA_ERROR);
616
GET_UCHAR(BZ_X_ENDHDR_4, uc);
617
if (uc != 0x38) RETURN(BZ_DATA_ERROR);
618
GET_UCHAR(BZ_X_ENDHDR_5, uc);
619
if (uc != 0x50) RETURN(BZ_DATA_ERROR);
620
GET_UCHAR(BZ_X_ENDHDR_6, uc);
621
if (uc != 0x90) RETURN(BZ_DATA_ERROR);
623
s->storedCombinedCRC = 0;
624
GET_UCHAR(BZ_X_CCRC_1, uc);
625
s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
626
GET_UCHAR(BZ_X_CCRC_2, uc);
627
s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
628
GET_UCHAR(BZ_X_CCRC_3, uc);
629
s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
630
GET_UCHAR(BZ_X_CCRC_4, uc);
631
s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
633
s->state = BZ_X_IDLE;
634
RETURN(BZ_STREAM_END);
636
default: AssertH ( False, 4001 );
639
AssertH ( False, 4002 );
641
save_state_and_return:
646
s->save_alphaSize = alphaSize;
647
s->save_nGroups = nGroups;
648
s->save_nSelectors = nSelectors;
650
s->save_groupNo = groupNo;
651
s->save_groupPos = groupPos;
652
s->save_nextSym = nextSym;
653
s->save_nblockMAX = nblockMAX;
654
s->save_nblock = nblock;
663
s->save_gMinlen = gMinlen;
664
s->save_gLimit = gLimit;
665
s->save_gBase = gBase;
666
s->save_gPerm = gPerm;
672
/*-------------------------------------------------------------*/
673
/*--- end decompress.c ---*/
674
/*-------------------------------------------------------------*/