1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
|
/*
* bzip2 is written by Julian Seward <jseward@bzip.org>.
* Adapted for busybox by Denys Vlasenko <vda.linux@googlemail.com>.
* See README and LICENSE files in this directory for more information.
*/
/*-------------------------------------------------------------*/
/*--- Compression machinery (not incl block sorting) ---*/
/*--- compress.c ---*/
/*-------------------------------------------------------------*/
/* ------------------------------------------------------------------
This file is part of bzip2/libbzip2, a program and library for
lossless, block-sorting data compression.
bzip2/libbzip2 version 1.0.4 of 20 December 2006
Copyright (C) 1996-2006 Julian Seward <jseward@bzip.org>
Please read the WARNING, DISCLAIMER and PATENTS sections in the
README file.
This program is released under the terms of the license contained
in the file LICENSE.
------------------------------------------------------------------ */
/* CHANGES
* 0.9.0 -- original version.
* 0.9.0a/b -- no changes in this file.
* 0.9.0c -- changed setting of nGroups in sendMTFValues()
* so as to do a bit better on small files
*/
/* #include "bzlib_private.h" */
/*---------------------------------------------------*/
/*--- Bit stream I/O ---*/
/*---------------------------------------------------*/
/*---------------------------------------------------*/
static
void BZ2_bsInitWrite(EState* s)
{
s->bsLive = 0;
s->bsBuff = 0;
}
/*---------------------------------------------------*/
static NOINLINE
void bsFinishWrite(EState* s)
{
while (s->bsLive > 0) {
s->zbits[s->numZ] = (uint8_t)(s->bsBuff >> 24);
s->numZ++;
s->bsBuff <<= 8;
s->bsLive -= 8;
}
}
/*---------------------------------------------------*/
static
/* Helps only on level 5, on other levels hurts. ? */
#if CONFIG_BZIP2_FEATURE_SPEED >= 5
ALWAYS_INLINE
#endif
void bsW(EState* s, int32_t n, uint32_t v)
{
while (s->bsLive >= 8) {
s->zbits[s->numZ] = (uint8_t)(s->bsBuff >> 24);
s->numZ++;
s->bsBuff <<= 8;
s->bsLive -= 8;
}
s->bsBuff |= (v << (32 - s->bsLive - n));
s->bsLive += n;
}
/*---------------------------------------------------*/
static
void bsPutU32(EState* s, unsigned u)
{
bsW(s, 8, (u >> 24) & 0xff);
bsW(s, 8, (u >> 16) & 0xff);
bsW(s, 8, (u >> 8) & 0xff);
bsW(s, 8, u & 0xff);
}
/*---------------------------------------------------*/
static
void bsPutU16(EState* s, unsigned u)
{
bsW(s, 8, (u >> 8) & 0xff);
bsW(s, 8, u & 0xff);
}
/*---------------------------------------------------*/
/*--- The back end proper ---*/
/*---------------------------------------------------*/
/*---------------------------------------------------*/
static
void makeMaps_e(EState* s)
{
int i;
s->nInUse = 0;
for (i = 0; i < 256; i++) {
if (s->inUse[i]) {
s->unseqToSeq[i] = s->nInUse;
s->nInUse++;
}
}
}
/*---------------------------------------------------*/
static NOINLINE
void generateMTFValues(EState* s)
{
uint8_t yy[256];
int32_t i, j;
int32_t zPend;
int32_t wr;
int32_t EOB;
/*
* After sorting (eg, here),
* s->arr1[0 .. s->nblock-1] holds sorted order,
* and
* ((uint8_t*)s->arr2)[0 .. s->nblock-1]
* holds the original block data.
*
* The first thing to do is generate the MTF values,
* and put them in
* ((uint16_t*)s->arr1)[0 .. s->nblock-1].
* Because there are strictly fewer or equal MTF values
* than block values, ptr values in this area are overwritten
* with MTF values only when they are no longer needed.
*
* The final compressed bitstream is generated into the
* area starting at
* &((uint8_t*)s->arr2)[s->nblock]
*
* These storage aliases are set up in bzCompressInit(),
* except for the last one, which is arranged in
* compressBlock().
*/
uint32_t* ptr = s->ptr;
uint8_t* block = s->block;
uint16_t* mtfv = s->mtfv;
makeMaps_e(s);
EOB = s->nInUse+1;
for (i = 0; i <= EOB; i++)
s->mtfFreq[i] = 0;
wr = 0;
zPend = 0;
for (i = 0; i < s->nInUse; i++)
yy[i] = (uint8_t) i;
for (i = 0; i < s->nblock; i++) {
uint8_t ll_i;
AssertD(wr <= i, "generateMTFValues(1)");
j = ptr[i] - 1;
if (j < 0)
j += s->nblock;
ll_i = s->unseqToSeq[block[j]];
AssertD(ll_i < s->nInUse, "generateMTFValues(2a)");
if (yy[0] == ll_i) {
zPend++;
} else {
if (zPend > 0) {
zPend--;
while (1) {
if (zPend & 1) {
mtfv[wr] = BZ_RUNB; wr++;
s->mtfFreq[BZ_RUNB]++;
} else {
mtfv[wr] = BZ_RUNA; wr++;
s->mtfFreq[BZ_RUNA]++;
}
if (zPend < 2) break;
zPend = (zPend - 2) / 2;
};
zPend = 0;
}
{
register uint8_t rtmp;
register uint8_t* ryy_j;
register uint8_t rll_i;
rtmp = yy[1];
yy[1] = yy[0];
ryy_j = &(yy[1]);
rll_i = ll_i;
while (rll_i != rtmp) {
register uint8_t rtmp2;
ryy_j++;
rtmp2 = rtmp;
rtmp = *ryy_j;
*ryy_j = rtmp2;
};
yy[0] = rtmp;
j = ryy_j - &(yy[0]);
mtfv[wr] = j+1;
wr++;
s->mtfFreq[j+1]++;
}
}
}
if (zPend > 0) {
zPend--;
while (1) {
if (zPend & 1) {
mtfv[wr] = BZ_RUNB; wr++;
s->mtfFreq[BZ_RUNB]++;
} else {
mtfv[wr] = BZ_RUNA; wr++;
s->mtfFreq[BZ_RUNA]++;
}
if (zPend < 2)
break;
zPend = (zPend - 2) / 2;
};
zPend = 0;
}
mtfv[wr] = EOB;
wr++;
s->mtfFreq[EOB]++;
s->nMTF = wr;
}
/*---------------------------------------------------*/
#define BZ_LESSER_ICOST 0
#define BZ_GREATER_ICOST 15
static NOINLINE
void sendMTFValues(EState* s)
{
int32_t v, t, i, j, gs, ge, totc, bt, bc, iter;
int32_t nSelectors, alphaSize, minLen, maxLen, selCtr;
int32_t nGroups, nBytes;
/*
* uint8_t len[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
* is a global since the decoder also needs it.
*
* int32_t code[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
* int32_t rfreq[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
* are also globals only used in this proc.
* Made global to keep stack frame size small.
*/
uint16_t cost[BZ_N_GROUPS];
int32_t fave[BZ_N_GROUPS];
uint16_t* mtfv = s->mtfv;
alphaSize = s->nInUse+2;
for (t = 0; t < BZ_N_GROUPS; t++)
for (v = 0; v < alphaSize; v++)
s->len[t][v] = BZ_GREATER_ICOST;
/*--- Decide how many coding tables to use ---*/
AssertH(s->nMTF > 0, 3001);
if (s->nMTF < 200) nGroups = 2; else
if (s->nMTF < 600) nGroups = 3; else
if (s->nMTF < 1200) nGroups = 4; else
if (s->nMTF < 2400) nGroups = 5; else
nGroups = 6;
/*--- Generate an initial set of coding tables ---*/
{
int32_t nPart, remF, tFreq, aFreq;
nPart = nGroups;
remF = s->nMTF;
gs = 0;
while (nPart > 0) {
tFreq = remF / nPart;
ge = gs-1;
aFreq = 0;
while (aFreq < tFreq && ge < alphaSize-1) {
ge++;
aFreq += s->mtfFreq[ge];
}
if (ge > gs
&& nPart != nGroups && nPart != 1
&& ((nGroups - nPart) % 2 == 1)
) {
aFreq -= s->mtfFreq[ge];
ge--;
}
for (v = 0; v < alphaSize; v++)
if (v >= gs && v <= ge)
s->len[nPart-1][v] = BZ_LESSER_ICOST;
else
s->len[nPart-1][v] = BZ_GREATER_ICOST;
nPart--;
gs = ge+1;
remF -= aFreq;
}
}
/*
* Iterate up to BZ_N_ITERS times to improve the tables.
*/
for (iter = 0; iter < BZ_N_ITERS; iter++) {
for (t = 0; t < nGroups; t++)
fave[t] = 0;
for (t = 0; t < nGroups; t++)
for (v = 0; v < alphaSize; v++)
s->rfreq[t][v] = 0;
#if CONFIG_BZIP2_FEATURE_SPEED >= 5
/*
* Set up an auxiliary length table which is used to fast-track
* the common case (nGroups == 6).
*/
if (nGroups == 6) {
for (v = 0; v < alphaSize; v++) {
s->len_pack[v][0] = (s->len[1][v] << 16) | s->len[0][v];
s->len_pack[v][1] = (s->len[3][v] << 16) | s->len[2][v];
s->len_pack[v][2] = (s->len[5][v] << 16) | s->len[4][v];
}
}
#endif
nSelectors = 0;
totc = 0;
gs = 0;
while (1) {
/*--- Set group start & end marks. --*/
if (gs >= s->nMTF)
break;
ge = gs + BZ_G_SIZE - 1;
if (ge >= s->nMTF)
ge = s->nMTF-1;
/*
* Calculate the cost of this group as coded
* by each of the coding tables.
*/
for (t = 0; t < nGroups; t++)
cost[t] = 0;
#if CONFIG_BZIP2_FEATURE_SPEED >= 5
if (nGroups == 6 && 50 == ge-gs+1) {
/*--- fast track the common case ---*/
register uint32_t cost01, cost23, cost45;
register uint16_t icv;
cost01 = cost23 = cost45 = 0;
#define BZ_ITER(nn) \
icv = mtfv[gs+(nn)]; \
cost01 += s->len_pack[icv][0]; \
cost23 += s->len_pack[icv][1]; \
cost45 += s->len_pack[icv][2];
BZ_ITER(0); BZ_ITER(1); BZ_ITER(2); BZ_ITER(3); BZ_ITER(4);
BZ_ITER(5); BZ_ITER(6); BZ_ITER(7); BZ_ITER(8); BZ_ITER(9);
BZ_ITER(10); BZ_ITER(11); BZ_ITER(12); BZ_ITER(13); BZ_ITER(14);
BZ_ITER(15); BZ_ITER(16); BZ_ITER(17); BZ_ITER(18); BZ_ITER(19);
BZ_ITER(20); BZ_ITER(21); BZ_ITER(22); BZ_ITER(23); BZ_ITER(24);
BZ_ITER(25); BZ_ITER(26); BZ_ITER(27); BZ_ITER(28); BZ_ITER(29);
BZ_ITER(30); BZ_ITER(31); BZ_ITER(32); BZ_ITER(33); BZ_ITER(34);
BZ_ITER(35); BZ_ITER(36); BZ_ITER(37); BZ_ITER(38); BZ_ITER(39);
BZ_ITER(40); BZ_ITER(41); BZ_ITER(42); BZ_ITER(43); BZ_ITER(44);
BZ_ITER(45); BZ_ITER(46); BZ_ITER(47); BZ_ITER(48); BZ_ITER(49);
#undef BZ_ITER
cost[0] = cost01 & 0xffff; cost[1] = cost01 >> 16;
cost[2] = cost23 & 0xffff; cost[3] = cost23 >> 16;
cost[4] = cost45 & 0xffff; cost[5] = cost45 >> 16;
} else
#endif
{
/*--- slow version which correctly handles all situations ---*/
for (i = gs; i <= ge; i++) {
uint16_t icv = mtfv[i];
for (t = 0; t < nGroups; t++)
cost[t] += s->len[t][icv];
}
}
/*
* Find the coding table which is best for this group,
* and record its identity in the selector table.
*/
/*bc = 999999999;*/
/*bt = -1;*/
bc = cost[0];
bt = 0;
for (t = 1 /*0*/; t < nGroups; t++) {
if (cost[t] < bc) {
bc = cost[t];
bt = t;
}
}
totc += bc;
fave[bt]++;
s->selector[nSelectors] = bt;
nSelectors++;
/*
* Increment the symbol frequencies for the selected table.
*/
/* 1% faster compress. +800 bytes */
#if CONFIG_BZIP2_FEATURE_SPEED >= 4
if (nGroups == 6 && 50 == ge-gs+1) {
/*--- fast track the common case ---*/
#define BZ_ITUR(nn) s->rfreq[bt][mtfv[gs + (nn)]]++
BZ_ITUR(0); BZ_ITUR(1); BZ_ITUR(2); BZ_ITUR(3); BZ_ITUR(4);
BZ_ITUR(5); BZ_ITUR(6); BZ_ITUR(7); BZ_ITUR(8); BZ_ITUR(9);
BZ_ITUR(10); BZ_ITUR(11); BZ_ITUR(12); BZ_ITUR(13); BZ_ITUR(14);
BZ_ITUR(15); BZ_ITUR(16); BZ_ITUR(17); BZ_ITUR(18); BZ_ITUR(19);
BZ_ITUR(20); BZ_ITUR(21); BZ_ITUR(22); BZ_ITUR(23); BZ_ITUR(24);
BZ_ITUR(25); BZ_ITUR(26); BZ_ITUR(27); BZ_ITUR(28); BZ_ITUR(29);
BZ_ITUR(30); BZ_ITUR(31); BZ_ITUR(32); BZ_ITUR(33); BZ_ITUR(34);
BZ_ITUR(35); BZ_ITUR(36); BZ_ITUR(37); BZ_ITUR(38); BZ_ITUR(39);
BZ_ITUR(40); BZ_ITUR(41); BZ_ITUR(42); BZ_ITUR(43); BZ_ITUR(44);
BZ_ITUR(45); BZ_ITUR(46); BZ_ITUR(47); BZ_ITUR(48); BZ_ITUR(49);
#undef BZ_ITUR
gs = ge + 1;
} else
#endif
{
/*--- slow version which correctly handles all situations ---*/
while (gs <= ge) {
s->rfreq[bt][mtfv[gs]]++;
gs++;
}
/* already is: gs = ge + 1; */
}
}
/*
* Recompute the tables based on the accumulated frequencies.
*/
/* maxLen was changed from 20 to 17 in bzip2-1.0.3. See
* comment in huffman.c for details. */
for (t = 0; t < nGroups; t++)
BZ2_hbMakeCodeLengths(&(s->len[t][0]), &(s->rfreq[t][0]), alphaSize, 17 /*20*/);
}
AssertH(nGroups < 8, 3002);
AssertH(nSelectors < 32768 && nSelectors <= (2 + (900000 / BZ_G_SIZE)), 3003);
/*--- Compute MTF values for the selectors. ---*/
{
uint8_t pos[BZ_N_GROUPS], ll_i, tmp2, tmp;
for (i = 0; i < nGroups; i++)
pos[i] = i;
for (i = 0; i < nSelectors; i++) {
ll_i = s->selector[i];
j = 0;
tmp = pos[j];
while (ll_i != tmp) {
j++;
tmp2 = tmp;
tmp = pos[j];
pos[j] = tmp2;
};
pos[0] = tmp;
s->selectorMtf[i] = j;
}
};
/*--- Assign actual codes for the tables. --*/
for (t = 0; t < nGroups; t++) {
minLen = 32;
maxLen = 0;
for (i = 0; i < alphaSize; i++) {
if (s->len[t][i] > maxLen) maxLen = s->len[t][i];
if (s->len[t][i] < minLen) minLen = s->len[t][i];
}
AssertH(!(maxLen > 17 /*20*/), 3004);
AssertH(!(minLen < 1), 3005);
BZ2_hbAssignCodes(&(s->code[t][0]), &(s->len[t][0]), minLen, maxLen, alphaSize);
}
/*--- Transmit the mapping table. ---*/
{
/* bbox: optimized a bit more than in bzip2 */
int inUse16 = 0;
for (i = 0; i < 16; i++) {
if (sizeof(long) <= 4) {
inUse16 = inUse16*2 +
((*(uint32_t*)&(s->inUse[i * 16 + 0])
| *(uint32_t*)&(s->inUse[i * 16 + 4])
| *(uint32_t*)&(s->inUse[i * 16 + 8])
| *(uint32_t*)&(s->inUse[i * 16 + 12])) != 0);
} else { /* Our CPU can do better */
inUse16 = inUse16*2 +
((*(uint64_t*)&(s->inUse[i * 16 + 0])
| *(uint64_t*)&(s->inUse[i * 16 + 8])) != 0);
}
}
nBytes = s->numZ;
bsW(s, 16, inUse16);
inUse16 <<= (sizeof(int)*8 - 16); /* move 15th bit into sign bit */
for (i = 0; i < 16; i++) {
if (inUse16 < 0) {
unsigned v16 = 0;
for (j = 0; j < 16; j++)
v16 = v16*2 + s->inUse[i * 16 + j];
bsW(s, 16, v16);
}
inUse16 <<= 1;
}
}
/*--- Now the selectors. ---*/
nBytes = s->numZ;
bsW(s, 3, nGroups);
bsW(s, 15, nSelectors);
for (i = 0; i < nSelectors; i++) {
for (j = 0; j < s->selectorMtf[i]; j++)
bsW(s, 1, 1);
bsW(s, 1, 0);
}
/*--- Now the coding tables. ---*/
nBytes = s->numZ;
for (t = 0; t < nGroups; t++) {
int32_t curr = s->len[t][0];
bsW(s, 5, curr);
for (i = 0; i < alphaSize; i++) {
while (curr < s->len[t][i]) { bsW(s, 2, 2); curr++; /* 10 */ };
while (curr > s->len[t][i]) { bsW(s, 2, 3); curr--; /* 11 */ };
bsW(s, 1, 0);
}
}
/*--- And finally, the block data proper ---*/
nBytes = s->numZ;
selCtr = 0;
gs = 0;
while (1) {
if (gs >= s->nMTF)
break;
ge = gs + BZ_G_SIZE - 1;
if (ge >= s->nMTF)
ge = s->nMTF-1;
AssertH(s->selector[selCtr] < nGroups, 3006);
/* Costs 1300 bytes and is _slower_ (on Intel Core 2) */
#if 0
if (nGroups == 6 && 50 == ge-gs+1) {
/*--- fast track the common case ---*/
uint16_t mtfv_i;
uint8_t* s_len_sel_selCtr = &(s->len[s->selector[selCtr]][0]);
int32_t* s_code_sel_selCtr = &(s->code[s->selector[selCtr]][0]);
#define BZ_ITAH(nn) \
mtfv_i = mtfv[gs+(nn)]; \
bsW(s, s_len_sel_selCtr[mtfv_i], s_code_sel_selCtr[mtfv_i])
BZ_ITAH(0); BZ_ITAH(1); BZ_ITAH(2); BZ_ITAH(3); BZ_ITAH(4);
BZ_ITAH(5); BZ_ITAH(6); BZ_ITAH(7); BZ_ITAH(8); BZ_ITAH(9);
BZ_ITAH(10); BZ_ITAH(11); BZ_ITAH(12); BZ_ITAH(13); BZ_ITAH(14);
BZ_ITAH(15); BZ_ITAH(16); BZ_ITAH(17); BZ_ITAH(18); BZ_ITAH(19);
BZ_ITAH(20); BZ_ITAH(21); BZ_ITAH(22); BZ_ITAH(23); BZ_ITAH(24);
BZ_ITAH(25); BZ_ITAH(26); BZ_ITAH(27); BZ_ITAH(28); BZ_ITAH(29);
BZ_ITAH(30); BZ_ITAH(31); BZ_ITAH(32); BZ_ITAH(33); BZ_ITAH(34);
BZ_ITAH(35); BZ_ITAH(36); BZ_ITAH(37); BZ_ITAH(38); BZ_ITAH(39);
BZ_ITAH(40); BZ_ITAH(41); BZ_ITAH(42); BZ_ITAH(43); BZ_ITAH(44);
BZ_ITAH(45); BZ_ITAH(46); BZ_ITAH(47); BZ_ITAH(48); BZ_ITAH(49);
#undef BZ_ITAH
gs = ge+1;
} else
#endif
{
/*--- slow version which correctly handles all situations ---*/
/* code is bit bigger, but moves multiply out of the loop */
uint8_t* s_len_sel_selCtr = &(s->len [s->selector[selCtr]][0]);
int32_t* s_code_sel_selCtr = &(s->code[s->selector[selCtr]][0]);
while (gs <= ge) {
bsW(s,
s_len_sel_selCtr[mtfv[gs]],
s_code_sel_selCtr[mtfv[gs]]
);
gs++;
}
/* already is: gs = ge+1; */
}
selCtr++;
}
AssertH(selCtr == nSelectors, 3007);
}
/*---------------------------------------------------*/
static
void BZ2_compressBlock(EState* s, int is_last_block)
{
if (s->nblock > 0) {
BZ_FINALISE_CRC(s->blockCRC);
s->combinedCRC = (s->combinedCRC << 1) | (s->combinedCRC >> 31);
s->combinedCRC ^= s->blockCRC;
if (s->blockNo > 1)
s->numZ = 0;
BZ2_blockSort(s);
}
s->zbits = &((uint8_t*)s->arr2)[s->nblock];
/*-- If this is the first block, create the stream header. --*/
if (s->blockNo == 1) {
BZ2_bsInitWrite(s);
/*bsPutU8(s, BZ_HDR_B);*/
/*bsPutU8(s, BZ_HDR_Z);*/
/*bsPutU8(s, BZ_HDR_h);*/
/*bsPutU8(s, BZ_HDR_0 + s->blockSize100k);*/
bsPutU32(s, BZ_HDR_BZh0 + s->blockSize100k);
}
if (s->nblock > 0) {
/*bsPutU8(s, 0x31);*/
/*bsPutU8(s, 0x41);*/
/*bsPutU8(s, 0x59);*/
/*bsPutU8(s, 0x26);*/
bsPutU32(s, 0x31415926);
/*bsPutU8(s, 0x53);*/
/*bsPutU8(s, 0x59);*/
bsPutU16(s, 0x5359);
/*-- Now the block's CRC, so it is in a known place. --*/
bsPutU32(s, s->blockCRC);
/*
* Now a single bit indicating (non-)randomisation.
* As of version 0.9.5, we use a better sorting algorithm
* which makes randomisation unnecessary. So always set
* the randomised bit to 'no'. Of course, the decoder
* still needs to be able to handle randomised blocks
* so as to maintain backwards compatibility with
* older versions of bzip2.
*/
bsW(s, 1, 0);
bsW(s, 24, s->origPtr);
generateMTFValues(s);
sendMTFValues(s);
}
/*-- If this is the last block, add the stream trailer. --*/
if (is_last_block) {
/*bsPutU8(s, 0x17);*/
/*bsPutU8(s, 0x72);*/
/*bsPutU8(s, 0x45);*/
/*bsPutU8(s, 0x38);*/
bsPutU32(s, 0x17724538);
/*bsPutU8(s, 0x50);*/
/*bsPutU8(s, 0x90);*/
bsPutU16(s, 0x5090);
bsPutU32(s, s->combinedCRC);
bsFinishWrite(s);
}
}
/*-------------------------------------------------------------*/
/*--- end compress.c ---*/
/*-------------------------------------------------------------*/
|