| /* |
| * 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_FAST >= 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 = (uint32_t)(zPend - 2) / 2; |
| /* bbox: unsigned div is easier */ |
| }; |
| 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 = (uint32_t)(zPend - 2) / 2; |
| /* bbox: unsigned div is easier */ |
| }; |
| 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, bt, bc, iter; |
| int32_t nSelectors, alphaSize, minLen, maxLen, selCtr; |
| int32_t nGroups; |
| |
| /* |
| * 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. |
| */ |
| #define code sendMTFValues__code |
| #define rfreq sendMTFValues__rfreq |
| #define len_pack sendMTFValues__len_pack |
| |
| 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) /* bbox: can this be replaced by x & 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_FAST >= 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; |
| 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_FAST >= 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; |
| } |
| } |
| fave[bt]++; |
| s->selector[nSelectors] = bt; |
| nSelectors++; |
| |
| /* |
| * Increment the symbol frequencies for the selected table. |
| */ |
| /* 1% faster compress. +800 bytes */ |
| #if CONFIG_BZIP2_FAST >= 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, &(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 + |
| ((*(bb__aliased_uint32_t*)&(s->inUse[i * 16 + 0]) |
| | *(bb__aliased_uint32_t*)&(s->inUse[i * 16 + 4]) |
| | *(bb__aliased_uint32_t*)&(s->inUse[i * 16 + 8]) |
| | *(bb__aliased_uint32_t*)&(s->inUse[i * 16 + 12])) != 0); |
| } else { /* Our CPU can do better */ |
| inUse16 = inUse16*2 + |
| ((*(bb__aliased_uint64_t*)&(s->inUse[i * 16 + 0]) |
| | *(bb__aliased_uint64_t*)&(s->inUse[i * 16 + 8])) != 0); |
| } |
| } |
| |
| 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. ---*/ |
| 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. ---*/ |
| 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 ---*/ |
| 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); |
| #undef code |
| #undef rfreq |
| #undef len_pack |
| } |
| |
| |
| /*---------------------------------------------------*/ |
| 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 ---*/ |
| /*-------------------------------------------------------------*/ |