The Tor Browser: modules/libbz2/src/compress.c@129ffea94266 (annotated)

modules/libbz2/src/compress.c@129ffea94266 (annotated)

modules/libbz2/src/compress.c

Sat, 03 Jan 2015 20:18:00 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Sat, 03 Jan 2015 20:18:00 +0100
branch: TOR_BUG_3246
changeset 7: 129ffea94266
permissions: -rw-r--r--

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

 /*-------------------------------------------------------------*/
 /*--- 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
 .9.0    -- original version.
 .9.0a/b -- no changes in this file.
 .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                              ---*/
 /*---------------------------------------------------*/
 /*---------------------------------------------------*/
 void BZ2_bsInitWrite ( EState* s )
 {
    s->bsLive = 0;
    s->bsBuff = 0;
 }
 /*---------------------------------------------------*/
 static
 void bsFinishWrite ( EState* s )
 {
    while (s->bsLive > 0) {
       s->zbits[s->numZ] = (UChar)(s->bsBuff >> 24);
       s->numZ++;
       s->bsBuff <<= 8;
       s->bsLive -= 8;
    }
 }
 /*---------------------------------------------------*/
 #define bsNEEDW(nz)                           \
 {                                             \
    while (s->bsLive >= 8) {                   \
       s->zbits[s->numZ]                       \
          = (UChar)(s->bsBuff >> 24);          \
       s->numZ++;                              \
       s->bsBuff <<= 8;                        \
       s->bsLive -= 8;                         \
    }                                          \
 }
 /*---------------------------------------------------*/
 static
 __inline__
 void bsW ( EState* s, Int32 n, UInt32 v )
 {
    bsNEEDW ( n );
    s->bsBuff |= (v << (32 - s->bsLive - n));
    s->bsLive += n;
 }
 /*---------------------------------------------------*/
 static
 void bsPutUInt32 ( EState* s, UInt32 u )
 {
    bsW ( s, 8, (u >> 24) & 0xffL );
    bsW ( s, 8, (u >> 16) & 0xffL );
    bsW ( s, 8, (u >>  8) & 0xffL );
    bsW ( s, 8,  u        & 0xffL );
 }
 /*---------------------------------------------------*/
 static
 void bsPutUChar ( EState* s, UChar c )
 {
    bsW( s, 8, (UInt32)c );
 }
 /*---------------------------------------------------*/
 /*--- The back end proper                         ---*/
 /*---------------------------------------------------*/
 /*---------------------------------------------------*/
 static
 void makeMaps_e ( EState* s )
 {
    Int32 i;
    s->nInUse = 0;
    for (i = 0; i < 256; i++)
       if (s->inUse[i]) {
          s->unseqToSeq[i] = s->nInUse;
          s->nInUse++;
       }
 }
 /*---------------------------------------------------*/
 static
 void generateMTFValues ( EState* s )
 {
    UChar   yy[256];
    Int32   i, j;
    Int32   zPend;
    Int32   wr;
    Int32   EOB;
    /*
       After sorting (eg, here),
          s->arr1 [ 0 .. s->nblock-1 ] holds sorted order,
          and
          ((UChar*)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*)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
          (UChar*) (&((UChar*)s->arr2)[s->nblock])
       These storage aliases are set up in bzCompressInit(),
       except for the last one, which is arranged in
       compressBlock().
    */
    UInt32* ptr   = s->ptr;
    UChar* block  = s->block;
    UInt16* 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] = (UChar) i;
    for (i = 0; i < s->nblock; i++) {
       UChar 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 (True) {
                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 UChar  rtmp;
             register UChar* ryy_j;
             register UChar  rll_i;
             rtmp  = yy[1];
             yy[1] = yy[0];
             ryy_j = &(yy[1]);
             rll_i = ll_i;
             while ( rll_i != rtmp ) {
                register UChar 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 (True) {
          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
 void sendMTFValues ( EState* s )
 {
    Int32 v, t, i, j, gs, ge, totc, bt, bc, iter;
    Int32 nSelectors, alphaSize, minLen, maxLen, selCtr;
    Int32 nGroups, nBytes;
    /*--
    UChar  len [BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
    is a global since the decoder also needs it.
    Int32  code[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
    Int32  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 cost[BZ_N_GROUPS];
    Int32  fave[BZ_N_GROUPS];
    UInt16* mtfv = s->mtfv;
    if (s->verbosity >= 3)
       VPrintf3( "      %d in block, %d after MTF & 1-2 coding, "
                 "%d+2 syms in use\n",
                 s->nblock, s->nMTF, s->nInUse );
    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 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--;
          }
          if (s->verbosity >= 3)
             VPrintf5( "      initial group %d, [%d .. %d], "
                       "has %d syms (%4.1f%%)\n",
                       nPart, gs, ge, aFreq,
                       (100.0 * (float)aFreq) / (float)(s->nMTF) );
          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;
       /*---
         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];
 	 }
       }
       nSelectors = 0;
       totc = 0;
       gs = 0;
       while (True) {
          /*--- 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 (nGroups == 6 && 50 == ge-gs+1) {
             /*--- fast track the common case ---*/
             register UInt32 cost01, cost23, cost45;
             register UInt16 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 {
 	    /*--- slow version which correctly handles all situations ---*/
             for (i = gs; i <= ge; i++) {
                UInt16 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;
          for (t = 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.
           --*/
          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
          } else {
 	    /*--- slow version which correctly handles all situations ---*/
             for (i = gs; i <= ge; i++)
                s->rfreq[bt][ mtfv[i] ]++;
          }
          gs = ge+1;
       }
       if (s->verbosity >= 3) {
          VPrintf2 ( "      pass %d: size is %d, grp uses are ",
                    iter+1, totc/8 );
          for (t = 0; t < nGroups; t++)
             VPrintf1 ( "%d ", fave[t] );
          VPrintf0 ( "\n" );
       }
       /*--
         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)),
 );
    /*--- Compute MTF values for the selectors. ---*/
    {
       UChar 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. ---*/
    {
       Bool inUse16[16];
       for (i = 0; i < 16; i++) {
           inUse16[i] = False;
           for (j = 0; j < 16; j++)
              if (s->inUse[i * 16 + j]) inUse16[i] = True;
       }
       nBytes = s->numZ;
       for (i = 0; i < 16; i++)
          if (inUse16[i]) bsW(s,1,1); else bsW(s,1,0);
       for (i = 0; i < 16; i++)
          if (inUse16[i])
             for (j = 0; j < 16; j++) {
                if (s->inUse[i * 16 + j]) bsW(s,1,1); else bsW(s,1,0);
             }
       if (s->verbosity >= 3)
          VPrintf1( "      bytes: mapping %d, ", s->numZ-nBytes );
    }
    /*--- 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);
    }
    if (s->verbosity >= 3)
       VPrintf1( "selectors %d, ", s->numZ-nBytes );
    /*--- Now the coding tables. ---*/
    nBytes = s->numZ;
    for (t = 0; t < nGroups; t++) {
       Int32 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 );
       }
    }
    if (s->verbosity >= 3)
       VPrintf1 ( "code lengths %d, ", s->numZ-nBytes );
    /*--- And finally, the block data proper ---*/
    nBytes = s->numZ;
    selCtr = 0;
    gs = 0;
    while (True) {
       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 );
       if (nGroups == 6 && 50 == ge-gs+1) {
             /*--- fast track the common case ---*/
             UInt16 mtfv_i;
             UChar* s_len_sel_selCtr
                = &(s->len[s->selector[selCtr]][0]);
             Int32* 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
       } else {
 	 /*--- slow version which correctly handles all situations ---*/
          for (i = gs; i <= ge; i++) {
             bsW ( s,
                   s->len  [s->selector[selCtr]] [mtfv[i]],
                   s->code [s->selector[selCtr]] [mtfv[i]] );
          }
       }
       gs = ge+1;
       selCtr++;
    }
    AssertH( selCtr == nSelectors, 3007 );
    if (s->verbosity >= 3)
       VPrintf1( "codes %d\n", s->numZ-nBytes );
 }
 /*---------------------------------------------------*/
 void BZ2_compressBlock ( EState* s, Bool 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;
       if (s->verbosity >= 2)
          VPrintf4( "    block %d: crc = 0x%08x, "
                    "combined CRC = 0x%08x, size = %d\n",
                    s->blockNo, s->blockCRC, s->combinedCRC, s->nblock );
       BZ2_blockSort ( s );
    }
    s->zbits = (UChar*) (&((UChar*)s->arr2)[s->nblock]);
    /*-- If this is the first block, create the stream header. --*/
    if (s->blockNo == 1) {
       BZ2_bsInitWrite ( s );
       bsPutUChar ( s, BZ_HDR_B );
       bsPutUChar ( s, BZ_HDR_Z );
       bsPutUChar ( s, BZ_HDR_h );
       bsPutUChar ( s, (UChar)(BZ_HDR_0 + s->blockSize100k) );
    }
    if (s->nblock > 0) {
       bsPutUChar ( s, 0x31 ); bsPutUChar ( s, 0x41 );
       bsPutUChar ( s, 0x59 ); bsPutUChar ( s, 0x26 );
       bsPutUChar ( s, 0x53 ); bsPutUChar ( s, 0x59 );
       /*-- Now the block's CRC, so it is in a known place. --*/
       bsPutUInt32 ( 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) {
       bsPutUChar ( s, 0x17 ); bsPutUChar ( s, 0x72 );
       bsPutUChar ( s, 0x45 ); bsPutUChar ( s, 0x38 );
       bsPutUChar ( s, 0x50 ); bsPutUChar ( s, 0x90 );
       bsPutUInt32 ( s, s->combinedCRC );
       if (s->verbosity >= 2)
          VPrintf1( "    final combined CRC = 0x%08x\n   ", s->combinedCRC );
       bsFinishWrite ( s );
    }
 }
 /*-------------------------------------------------------------*/
 /*--- end                                        compress.c ---*/
 /*-------------------------------------------------------------*/

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modules/libbz2/src/compress.c@129ffea94266 (annotated)

modules/libbz2/src/compress.c