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Denis Vlasenko77f1ec12007-10-13 03:36:03 +00001/*
2 * bzip2 is written by Julian Seward <jseward@bzip.org>.
3 * Adapted for busybox by Denys Vlasenko <vda.linux@googlemail.com>.
4 * See README and LICENSE files in this directory for more information.
5 */
6
7/*-------------------------------------------------------------*/
8/*--- Compression machinery (not incl block sorting) ---*/
9/*--- compress.c ---*/
10/*-------------------------------------------------------------*/
11
12/* ------------------------------------------------------------------
13This file is part of bzip2/libbzip2, a program and library for
14lossless, block-sorting data compression.
15
16bzip2/libbzip2 version 1.0.4 of 20 December 2006
17Copyright (C) 1996-2006 Julian Seward <jseward@bzip.org>
18
19Please read the WARNING, DISCLAIMER and PATENTS sections in the
20README file.
21
22This program is released under the terms of the license contained
23in the file LICENSE.
24------------------------------------------------------------------ */
25
26/* CHANGES
27 * 0.9.0 -- original version.
28 * 0.9.0a/b -- no changes in this file.
29 * 0.9.0c -- changed setting of nGroups in sendMTFValues()
30 * so as to do a bit better on small files
31*/
32
33/* #include "bzlib_private.h" */
34
35/*---------------------------------------------------*/
36/*--- Bit stream I/O ---*/
37/*---------------------------------------------------*/
38
39/*---------------------------------------------------*/
40static
41void BZ2_bsInitWrite(EState* s)
42{
43 s->bsLive = 0;
44 s->bsBuff = 0;
45}
46
47
48/*---------------------------------------------------*/
49static NOINLINE
50void bsFinishWrite(EState* s)
51{
52 while (s->bsLive > 0) {
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +000053 s->zbits[s->numZ] = (uint8_t)(s->bsBuff >> 24);
Denis Vlasenko77f1ec12007-10-13 03:36:03 +000054 s->numZ++;
55 s->bsBuff <<= 8;
56 s->bsLive -= 8;
57 }
58}
59
60
61/*---------------------------------------------------*/
62static
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +000063/* Helps only on level 5, on other levels hurts. ? */
64#if CONFIG_BZIP2_FEATURE_SPEED >= 5
65ALWAYS_INLINE
66#endif
Denis Vlasenko77f1ec12007-10-13 03:36:03 +000067void bsW(EState* s, int32_t n, uint32_t v)
68{
69 while (s->bsLive >= 8) {
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +000070 s->zbits[s->numZ] = (uint8_t)(s->bsBuff >> 24);
Denis Vlasenko77f1ec12007-10-13 03:36:03 +000071 s->numZ++;
72 s->bsBuff <<= 8;
73 s->bsLive -= 8;
74 }
75 s->bsBuff |= (v << (32 - s->bsLive - n));
76 s->bsLive += n;
77}
78
79
80/*---------------------------------------------------*/
81static
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +000082void bsPutU32(EState* s, unsigned u)
Denis Vlasenko77f1ec12007-10-13 03:36:03 +000083{
84 bsW(s, 8, (u >> 24) & 0xff);
85 bsW(s, 8, (u >> 16) & 0xff);
86 bsW(s, 8, (u >> 8) & 0xff);
87 bsW(s, 8, u & 0xff);
88}
89
90
91/*---------------------------------------------------*/
92static
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +000093void bsPutU16(EState* s, unsigned u)
Denis Vlasenko77f1ec12007-10-13 03:36:03 +000094{
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +000095 bsW(s, 8, (u >> 8) & 0xff);
96 bsW(s, 8, u & 0xff);
Denis Vlasenko77f1ec12007-10-13 03:36:03 +000097}
98
99
100/*---------------------------------------------------*/
101/*--- The back end proper ---*/
102/*---------------------------------------------------*/
103
104/*---------------------------------------------------*/
105static
106void makeMaps_e(EState* s)
107{
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000108 int i;
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000109 s->nInUse = 0;
110 for (i = 0; i < 256; i++) {
111 if (s->inUse[i]) {
112 s->unseqToSeq[i] = s->nInUse;
113 s->nInUse++;
114 }
115 }
116}
117
118
119/*---------------------------------------------------*/
120static NOINLINE
121void generateMTFValues(EState* s)
122{
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000123 uint8_t yy[256];
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000124 int32_t i, j;
125 int32_t zPend;
126 int32_t wr;
127 int32_t EOB;
128
129 /*
130 * After sorting (eg, here),
131 * s->arr1[0 .. s->nblock-1] holds sorted order,
132 * and
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000133 * ((uint8_t*)s->arr2)[0 .. s->nblock-1]
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000134 * holds the original block data.
135 *
136 * The first thing to do is generate the MTF values,
137 * and put them in
138 * ((uint16_t*)s->arr1)[0 .. s->nblock-1].
139 * Because there are strictly fewer or equal MTF values
140 * than block values, ptr values in this area are overwritten
141 * with MTF values only when they are no longer needed.
142 *
143 * The final compressed bitstream is generated into the
144 * area starting at
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000145 * &((uint8_t*)s->arr2)[s->nblock]
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000146 *
147 * These storage aliases are set up in bzCompressInit(),
148 * except for the last one, which is arranged in
149 * compressBlock().
150 */
151 uint32_t* ptr = s->ptr;
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000152 uint8_t* block = s->block;
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000153 uint16_t* mtfv = s->mtfv;
154
155 makeMaps_e(s);
156 EOB = s->nInUse+1;
157
158 for (i = 0; i <= EOB; i++)
159 s->mtfFreq[i] = 0;
160
161 wr = 0;
162 zPend = 0;
163 for (i = 0; i < s->nInUse; i++)
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000164 yy[i] = (uint8_t) i;
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000165
166 for (i = 0; i < s->nblock; i++) {
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000167 uint8_t ll_i;
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000168 AssertD(wr <= i, "generateMTFValues(1)");
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000169 j = ptr[i] - 1;
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000170 if (j < 0)
171 j += s->nblock;
172 ll_i = s->unseqToSeq[block[j]];
173 AssertD(ll_i < s->nInUse, "generateMTFValues(2a)");
174
175 if (yy[0] == ll_i) {
176 zPend++;
177 } else {
178 if (zPend > 0) {
179 zPend--;
180 while (1) {
181 if (zPend & 1) {
182 mtfv[wr] = BZ_RUNB; wr++;
183 s->mtfFreq[BZ_RUNB]++;
184 } else {
185 mtfv[wr] = BZ_RUNA; wr++;
186 s->mtfFreq[BZ_RUNA]++;
187 }
188 if (zPend < 2) break;
189 zPend = (zPend - 2) / 2;
190 };
191 zPend = 0;
192 }
193 {
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000194 register uint8_t rtmp;
195 register uint8_t* ryy_j;
196 register uint8_t rll_i;
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000197 rtmp = yy[1];
198 yy[1] = yy[0];
199 ryy_j = &(yy[1]);
200 rll_i = ll_i;
201 while (rll_i != rtmp) {
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000202 register uint8_t rtmp2;
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000203 ryy_j++;
204 rtmp2 = rtmp;
205 rtmp = *ryy_j;
206 *ryy_j = rtmp2;
207 };
208 yy[0] = rtmp;
209 j = ryy_j - &(yy[0]);
210 mtfv[wr] = j+1;
211 wr++;
212 s->mtfFreq[j+1]++;
213 }
214
215 }
216 }
217
218 if (zPend > 0) {
219 zPend--;
220 while (1) {
221 if (zPend & 1) {
222 mtfv[wr] = BZ_RUNB; wr++;
223 s->mtfFreq[BZ_RUNB]++;
224 } else {
225 mtfv[wr] = BZ_RUNA; wr++;
226 s->mtfFreq[BZ_RUNA]++;
227 }
228 if (zPend < 2)
229 break;
230 zPend = (zPend - 2) / 2;
231 };
232 zPend = 0;
233 }
234
235 mtfv[wr] = EOB;
236 wr++;
237 s->mtfFreq[EOB]++;
238
239 s->nMTF = wr;
240}
241
242
243/*---------------------------------------------------*/
244#define BZ_LESSER_ICOST 0
245#define BZ_GREATER_ICOST 15
246
247static NOINLINE
248void sendMTFValues(EState* s)
249{
250 int32_t v, t, i, j, gs, ge, totc, bt, bc, iter;
251 int32_t nSelectors, alphaSize, minLen, maxLen, selCtr;
252 int32_t nGroups, nBytes;
253
254 /*
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000255 * uint8_t len[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000256 * is a global since the decoder also needs it.
257 *
258 * int32_t code[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
259 * int32_t rfreq[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
260 * are also globals only used in this proc.
261 * Made global to keep stack frame size small.
262 */
263
264 uint16_t cost[BZ_N_GROUPS];
265 int32_t fave[BZ_N_GROUPS];
266
267 uint16_t* mtfv = s->mtfv;
268
269 alphaSize = s->nInUse+2;
270 for (t = 0; t < BZ_N_GROUPS; t++)
271 for (v = 0; v < alphaSize; v++)
272 s->len[t][v] = BZ_GREATER_ICOST;
273
274 /*--- Decide how many coding tables to use ---*/
275 AssertH(s->nMTF > 0, 3001);
276 if (s->nMTF < 200) nGroups = 2; else
277 if (s->nMTF < 600) nGroups = 3; else
278 if (s->nMTF < 1200) nGroups = 4; else
279 if (s->nMTF < 2400) nGroups = 5; else
280 nGroups = 6;
281
282 /*--- Generate an initial set of coding tables ---*/
283 {
284 int32_t nPart, remF, tFreq, aFreq;
285
286 nPart = nGroups;
287 remF = s->nMTF;
288 gs = 0;
289 while (nPart > 0) {
290 tFreq = remF / nPart;
291 ge = gs-1;
292 aFreq = 0;
293 while (aFreq < tFreq && ge < alphaSize-1) {
294 ge++;
295 aFreq += s->mtfFreq[ge];
296 }
297
298 if (ge > gs
299 && nPart != nGroups && nPart != 1
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000300 && ((nGroups - nPart) % 2 == 1)
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000301 ) {
302 aFreq -= s->mtfFreq[ge];
303 ge--;
304 }
305
306 for (v = 0; v < alphaSize; v++)
307 if (v >= gs && v <= ge)
308 s->len[nPart-1][v] = BZ_LESSER_ICOST;
309 else
310 s->len[nPart-1][v] = BZ_GREATER_ICOST;
311
312 nPart--;
313 gs = ge+1;
314 remF -= aFreq;
315 }
316 }
317
318 /*
319 * Iterate up to BZ_N_ITERS times to improve the tables.
320 */
321 for (iter = 0; iter < BZ_N_ITERS; iter++) {
322 for (t = 0; t < nGroups; t++)
323 fave[t] = 0;
324
325 for (t = 0; t < nGroups; t++)
326 for (v = 0; v < alphaSize; v++)
327 s->rfreq[t][v] = 0;
328
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000329#if CONFIG_BZIP2_FEATURE_SPEED >= 5
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000330 /*
331 * Set up an auxiliary length table which is used to fast-track
332 * the common case (nGroups == 6).
333 */
334 if (nGroups == 6) {
335 for (v = 0; v < alphaSize; v++) {
336 s->len_pack[v][0] = (s->len[1][v] << 16) | s->len[0][v];
337 s->len_pack[v][1] = (s->len[3][v] << 16) | s->len[2][v];
338 s->len_pack[v][2] = (s->len[5][v] << 16) | s->len[4][v];
339 }
340 }
341#endif
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000342 nSelectors = 0;
343 totc = 0;
344 gs = 0;
345 while (1) {
346 /*--- Set group start & end marks. --*/
347 if (gs >= s->nMTF)
348 break;
349 ge = gs + BZ_G_SIZE - 1;
350 if (ge >= s->nMTF)
351 ge = s->nMTF-1;
352
353 /*
354 * Calculate the cost of this group as coded
355 * by each of the coding tables.
356 */
357 for (t = 0; t < nGroups; t++)
358 cost[t] = 0;
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000359#if CONFIG_BZIP2_FEATURE_SPEED >= 5
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000360 if (nGroups == 6 && 50 == ge-gs+1) {
361 /*--- fast track the common case ---*/
362 register uint32_t cost01, cost23, cost45;
363 register uint16_t icv;
364 cost01 = cost23 = cost45 = 0;
365#define BZ_ITER(nn) \
366 icv = mtfv[gs+(nn)]; \
367 cost01 += s->len_pack[icv][0]; \
368 cost23 += s->len_pack[icv][1]; \
369 cost45 += s->len_pack[icv][2];
370 BZ_ITER(0); BZ_ITER(1); BZ_ITER(2); BZ_ITER(3); BZ_ITER(4);
371 BZ_ITER(5); BZ_ITER(6); BZ_ITER(7); BZ_ITER(8); BZ_ITER(9);
372 BZ_ITER(10); BZ_ITER(11); BZ_ITER(12); BZ_ITER(13); BZ_ITER(14);
373 BZ_ITER(15); BZ_ITER(16); BZ_ITER(17); BZ_ITER(18); BZ_ITER(19);
374 BZ_ITER(20); BZ_ITER(21); BZ_ITER(22); BZ_ITER(23); BZ_ITER(24);
375 BZ_ITER(25); BZ_ITER(26); BZ_ITER(27); BZ_ITER(28); BZ_ITER(29);
376 BZ_ITER(30); BZ_ITER(31); BZ_ITER(32); BZ_ITER(33); BZ_ITER(34);
377 BZ_ITER(35); BZ_ITER(36); BZ_ITER(37); BZ_ITER(38); BZ_ITER(39);
378 BZ_ITER(40); BZ_ITER(41); BZ_ITER(42); BZ_ITER(43); BZ_ITER(44);
379 BZ_ITER(45); BZ_ITER(46); BZ_ITER(47); BZ_ITER(48); BZ_ITER(49);
380#undef BZ_ITER
381 cost[0] = cost01 & 0xffff; cost[1] = cost01 >> 16;
382 cost[2] = cost23 & 0xffff; cost[3] = cost23 >> 16;
383 cost[4] = cost45 & 0xffff; cost[5] = cost45 >> 16;
384
385 } else
386#endif
387 {
388 /*--- slow version which correctly handles all situations ---*/
389 for (i = gs; i <= ge; i++) {
390 uint16_t icv = mtfv[i];
391 for (t = 0; t < nGroups; t++)
392 cost[t] += s->len[t][icv];
393 }
394 }
395 /*
396 * Find the coding table which is best for this group,
397 * and record its identity in the selector table.
398 */
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000399 /*bc = 999999999;*/
400 /*bt = -1;*/
401 bc = cost[0];
402 bt = 0;
403 for (t = 1 /*0*/; t < nGroups; t++) {
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000404 if (cost[t] < bc) {
405 bc = cost[t];
406 bt = t;
407 }
408 }
409 totc += bc;
410 fave[bt]++;
411 s->selector[nSelectors] = bt;
412 nSelectors++;
413
414 /*
415 * Increment the symbol frequencies for the selected table.
416 */
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000417/* 1% faster compress. +800 bytes */
418#if CONFIG_BZIP2_FEATURE_SPEED >= 4
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000419 if (nGroups == 6 && 50 == ge-gs+1) {
420 /*--- fast track the common case ---*/
421#define BZ_ITUR(nn) s->rfreq[bt][mtfv[gs + (nn)]]++
422 BZ_ITUR(0); BZ_ITUR(1); BZ_ITUR(2); BZ_ITUR(3); BZ_ITUR(4);
423 BZ_ITUR(5); BZ_ITUR(6); BZ_ITUR(7); BZ_ITUR(8); BZ_ITUR(9);
424 BZ_ITUR(10); BZ_ITUR(11); BZ_ITUR(12); BZ_ITUR(13); BZ_ITUR(14);
425 BZ_ITUR(15); BZ_ITUR(16); BZ_ITUR(17); BZ_ITUR(18); BZ_ITUR(19);
426 BZ_ITUR(20); BZ_ITUR(21); BZ_ITUR(22); BZ_ITUR(23); BZ_ITUR(24);
427 BZ_ITUR(25); BZ_ITUR(26); BZ_ITUR(27); BZ_ITUR(28); BZ_ITUR(29);
428 BZ_ITUR(30); BZ_ITUR(31); BZ_ITUR(32); BZ_ITUR(33); BZ_ITUR(34);
429 BZ_ITUR(35); BZ_ITUR(36); BZ_ITUR(37); BZ_ITUR(38); BZ_ITUR(39);
430 BZ_ITUR(40); BZ_ITUR(41); BZ_ITUR(42); BZ_ITUR(43); BZ_ITUR(44);
431 BZ_ITUR(45); BZ_ITUR(46); BZ_ITUR(47); BZ_ITUR(48); BZ_ITUR(49);
432#undef BZ_ITUR
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000433 gs = ge + 1;
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000434 } else
435#endif
436 {
437 /*--- slow version which correctly handles all situations ---*/
438 while (gs <= ge) {
439 s->rfreq[bt][mtfv[gs]]++;
440 gs++;
441 }
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000442 /* already is: gs = ge + 1; */
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000443 }
444 }
445
446 /*
447 * Recompute the tables based on the accumulated frequencies.
448 */
449 /* maxLen was changed from 20 to 17 in bzip2-1.0.3. See
450 * comment in huffman.c for details. */
451 for (t = 0; t < nGroups; t++)
452 BZ2_hbMakeCodeLengths(&(s->len[t][0]), &(s->rfreq[t][0]), alphaSize, 17 /*20*/);
453 }
454
455 AssertH(nGroups < 8, 3002);
456 AssertH(nSelectors < 32768 && nSelectors <= (2 + (900000 / BZ_G_SIZE)), 3003);
457
458 /*--- Compute MTF values for the selectors. ---*/
459 {
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000460 uint8_t pos[BZ_N_GROUPS], ll_i, tmp2, tmp;
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000461
462 for (i = 0; i < nGroups; i++)
463 pos[i] = i;
464 for (i = 0; i < nSelectors; i++) {
465 ll_i = s->selector[i];
466 j = 0;
467 tmp = pos[j];
468 while (ll_i != tmp) {
469 j++;
470 tmp2 = tmp;
471 tmp = pos[j];
472 pos[j] = tmp2;
473 };
474 pos[0] = tmp;
475 s->selectorMtf[i] = j;
476 }
477 };
478
479 /*--- Assign actual codes for the tables. --*/
480 for (t = 0; t < nGroups; t++) {
481 minLen = 32;
482 maxLen = 0;
483 for (i = 0; i < alphaSize; i++) {
484 if (s->len[t][i] > maxLen) maxLen = s->len[t][i];
485 if (s->len[t][i] < minLen) minLen = s->len[t][i];
486 }
487 AssertH(!(maxLen > 17 /*20*/), 3004);
488 AssertH(!(minLen < 1), 3005);
489 BZ2_hbAssignCodes(&(s->code[t][0]), &(s->len[t][0]), minLen, maxLen, alphaSize);
490 }
491
492 /*--- Transmit the mapping table. ---*/
493 {
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000494 /* bbox: optimized a bit more than in bzip2 */
495 int inUse16 = 0;
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000496 for (i = 0; i < 16; i++) {
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000497 if (sizeof(long) <= 4) {
498 inUse16 = inUse16*2 +
499 ((*(uint32_t*)&(s->inUse[i * 16 + 0])
500 | *(uint32_t*)&(s->inUse[i * 16 + 4])
501 | *(uint32_t*)&(s->inUse[i * 16 + 8])
502 | *(uint32_t*)&(s->inUse[i * 16 + 12])) != 0);
503 } else { /* Our CPU can do better */
504 inUse16 = inUse16*2 +
505 ((*(uint64_t*)&(s->inUse[i * 16 + 0])
506 | *(uint64_t*)&(s->inUse[i * 16 + 8])) != 0);
507 }
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000508 }
509
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000510 nBytes = s->numZ;
511 bsW(s, 16, inUse16);
512
513 inUse16 <<= (sizeof(int)*8 - 16); /* move 15th bit into sign bit */
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000514 for (i = 0; i < 16; i++) {
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000515 if (inUse16 < 0) {
516 unsigned v16 = 0;
517 for (j = 0; j < 16; j++)
518 v16 = v16*2 + s->inUse[i * 16 + j];
519 bsW(s, 16, v16);
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000520 }
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000521 inUse16 <<= 1;
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000522 }
523 }
524
525 /*--- Now the selectors. ---*/
526 nBytes = s->numZ;
527 bsW(s, 3, nGroups);
528 bsW(s, 15, nSelectors);
529 for (i = 0; i < nSelectors; i++) {
530 for (j = 0; j < s->selectorMtf[i]; j++)
531 bsW(s, 1, 1);
532 bsW(s, 1, 0);
533 }
534
535 /*--- Now the coding tables. ---*/
536 nBytes = s->numZ;
537
538 for (t = 0; t < nGroups; t++) {
539 int32_t curr = s->len[t][0];
540 bsW(s, 5, curr);
541 for (i = 0; i < alphaSize; i++) {
542 while (curr < s->len[t][i]) { bsW(s, 2, 2); curr++; /* 10 */ };
543 while (curr > s->len[t][i]) { bsW(s, 2, 3); curr--; /* 11 */ };
544 bsW(s, 1, 0);
545 }
546 }
547
548 /*--- And finally, the block data proper ---*/
549 nBytes = s->numZ;
550 selCtr = 0;
551 gs = 0;
552 while (1) {
553 if (gs >= s->nMTF)
554 break;
555 ge = gs + BZ_G_SIZE - 1;
556 if (ge >= s->nMTF)
557 ge = s->nMTF-1;
558 AssertH(s->selector[selCtr] < nGroups, 3006);
559
560/* Costs 1300 bytes and is _slower_ (on Intel Core 2) */
561#if 0
562 if (nGroups == 6 && 50 == ge-gs+1) {
563 /*--- fast track the common case ---*/
564 uint16_t mtfv_i;
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000565 uint8_t* s_len_sel_selCtr = &(s->len[s->selector[selCtr]][0]);
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000566 int32_t* s_code_sel_selCtr = &(s->code[s->selector[selCtr]][0]);
567#define BZ_ITAH(nn) \
568 mtfv_i = mtfv[gs+(nn)]; \
569 bsW(s, s_len_sel_selCtr[mtfv_i], s_code_sel_selCtr[mtfv_i])
570 BZ_ITAH(0); BZ_ITAH(1); BZ_ITAH(2); BZ_ITAH(3); BZ_ITAH(4);
571 BZ_ITAH(5); BZ_ITAH(6); BZ_ITAH(7); BZ_ITAH(8); BZ_ITAH(9);
572 BZ_ITAH(10); BZ_ITAH(11); BZ_ITAH(12); BZ_ITAH(13); BZ_ITAH(14);
573 BZ_ITAH(15); BZ_ITAH(16); BZ_ITAH(17); BZ_ITAH(18); BZ_ITAH(19);
574 BZ_ITAH(20); BZ_ITAH(21); BZ_ITAH(22); BZ_ITAH(23); BZ_ITAH(24);
575 BZ_ITAH(25); BZ_ITAH(26); BZ_ITAH(27); BZ_ITAH(28); BZ_ITAH(29);
576 BZ_ITAH(30); BZ_ITAH(31); BZ_ITAH(32); BZ_ITAH(33); BZ_ITAH(34);
577 BZ_ITAH(35); BZ_ITAH(36); BZ_ITAH(37); BZ_ITAH(38); BZ_ITAH(39);
578 BZ_ITAH(40); BZ_ITAH(41); BZ_ITAH(42); BZ_ITAH(43); BZ_ITAH(44);
579 BZ_ITAH(45); BZ_ITAH(46); BZ_ITAH(47); BZ_ITAH(48); BZ_ITAH(49);
580#undef BZ_ITAH
581 gs = ge+1;
582 } else
583#endif
584 {
585 /*--- slow version which correctly handles all situations ---*/
586 /* code is bit bigger, but moves multiply out of the loop */
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000587 uint8_t* s_len_sel_selCtr = &(s->len [s->selector[selCtr]][0]);
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000588 int32_t* s_code_sel_selCtr = &(s->code[s->selector[selCtr]][0]);
589 while (gs <= ge) {
590 bsW(s,
591 s_len_sel_selCtr[mtfv[gs]],
592 s_code_sel_selCtr[mtfv[gs]]
593 );
594 gs++;
595 }
596 /* already is: gs = ge+1; */
597 }
598 selCtr++;
599 }
600 AssertH(selCtr == nSelectors, 3007);
601}
602
603
604/*---------------------------------------------------*/
605static
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000606void BZ2_compressBlock(EState* s, int is_last_block)
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000607{
608 if (s->nblock > 0) {
609 BZ_FINALISE_CRC(s->blockCRC);
610 s->combinedCRC = (s->combinedCRC << 1) | (s->combinedCRC >> 31);
611 s->combinedCRC ^= s->blockCRC;
612 if (s->blockNo > 1)
613 s->numZ = 0;
614
615 BZ2_blockSort(s);
616 }
617
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000618 s->zbits = &((uint8_t*)s->arr2)[s->nblock];
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000619
620 /*-- If this is the first block, create the stream header. --*/
621 if (s->blockNo == 1) {
622 BZ2_bsInitWrite(s);
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000623 /*bsPutU8(s, BZ_HDR_B);*/
624 /*bsPutU8(s, BZ_HDR_Z);*/
625 /*bsPutU8(s, BZ_HDR_h);*/
626 /*bsPutU8(s, BZ_HDR_0 + s->blockSize100k);*/
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000627 bsPutU32(s, BZ_HDR_BZh0 + s->blockSize100k);
628 }
629
630 if (s->nblock > 0) {
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000631 /*bsPutU8(s, 0x31);*/
632 /*bsPutU8(s, 0x41);*/
633 /*bsPutU8(s, 0x59);*/
634 /*bsPutU8(s, 0x26);*/
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000635 bsPutU32(s, 0x31415926);
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000636 /*bsPutU8(s, 0x53);*/
637 /*bsPutU8(s, 0x59);*/
638 bsPutU16(s, 0x5359);
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000639
640 /*-- Now the block's CRC, so it is in a known place. --*/
641 bsPutU32(s, s->blockCRC);
642
643 /*
644 * Now a single bit indicating (non-)randomisation.
645 * As of version 0.9.5, we use a better sorting algorithm
646 * which makes randomisation unnecessary. So always set
647 * the randomised bit to 'no'. Of course, the decoder
648 * still needs to be able to handle randomised blocks
649 * so as to maintain backwards compatibility with
650 * older versions of bzip2.
651 */
652 bsW(s, 1, 0);
653
654 bsW(s, 24, s->origPtr);
655 generateMTFValues(s);
656 sendMTFValues(s);
657 }
658
659 /*-- If this is the last block, add the stream trailer. --*/
660 if (is_last_block) {
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000661 /*bsPutU8(s, 0x17);*/
662 /*bsPutU8(s, 0x72);*/
663 /*bsPutU8(s, 0x45);*/
664 /*bsPutU8(s, 0x38);*/
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000665 bsPutU32(s, 0x17724538);
Denis Vlasenkoef3aabe2007-10-14 00:43:01 +0000666 /*bsPutU8(s, 0x50);*/
667 /*bsPutU8(s, 0x90);*/
668 bsPutU16(s, 0x5090);
Denis Vlasenko77f1ec12007-10-13 03:36:03 +0000669 bsPutU32(s, s->combinedCRC);
670 bsFinishWrite(s);
671 }
672}
673
674
675/*-------------------------------------------------------------*/
676/*--- end compress.c ---*/
677/*-------------------------------------------------------------*/