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bzip2-1.0.1

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This commit is contained in:
Julian Seward
2000-06-24 22:13:13 +02:00
parent f93cd82a9a
commit 795b859eee
27 changed files with 2164 additions and 919 deletions
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193
compress.c
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@@ -8,7 +8,7 @@
This file is a part of bzip2 and/or libbzip2, a program and
library for lossless, block-sorting data compression.
Copyright (C) 1996-1999 Julian R Seward. All rights reserved.
Copyright (C) 1996-2000 Julian R Seward. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
@@ -43,7 +43,7 @@
Julian Seward, Cambridge, UK.
jseward@acm.org
bzip2/libbzip2 version 0.9.5 of 24 May 1999
bzip2/libbzip2 version 1.0 of 21 March 2000
This program is based on (at least) the work of:
Mike Burrows
@@ -78,7 +78,7 @@
/*---------------------------------------------------*/
/*---------------------------------------------------*/
void bsInitWrite ( EState* s )
void BZ2_bsInitWrite ( EState* s )
{
s->bsLive = 0;
s->bsBuff = 0;
@@ -113,6 +113,7 @@ void bsFinishWrite ( EState* s )
/*---------------------------------------------------*/
static
__inline__
void bsW ( EState* s, Int32 n, UInt32 v )
{
bsNEEDW ( n );
@@ -164,8 +165,6 @@ void generateMTFValues ( EState* s )
{
UChar yy[256];
Int32 i, j;
UChar tmp;
UChar tmp2;
Int32 zPend;
Int32 wr;
Int32 EOB;
@@ -174,7 +173,7 @@ void generateMTFValues ( EState* s )
After sorting (eg, here),
s->arr1 [ 0 .. s->nblock-1 ] holds sorted order,
and
((UInt16*)s->arr2) [ 0 .. s->nblock-1 ] [15:8]
((UChar*)s->arr2) [ 0 .. s->nblock-1 ]
holds the original block data.
The first thing to do is generate the MTF values,
@@ -186,14 +185,14 @@ void generateMTFValues ( EState* s )
The final compressed bitstream is generated into the
area starting at
(UChar*) (&((UInt16)s->arr2)[s->nblock])
(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;
UInt16* block = s->block;
UChar* block = s->block;
UInt16* mtfv = s->mtfv;
makeMaps_e ( s );
@@ -207,27 +206,14 @@ void generateMTFValues ( EState* s )
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] >> 8];
ll_i = s->unseqToSeq[block[j]];
AssertD ( ll_i < s->nInUse, "generateMTFValues(2a)" );
tmp = yy[0];
if (tmp == ll_i) {
if (yy[0] == ll_i) {
zPend++;
} else {
tmp2 = tmp;
tmp = yy[1];
yy[1] = tmp2;
j = 1;
while ( ll_i != tmp ) {
j++;
tmp2 = tmp;
tmp = yy[j];
yy[j] = tmp2;
};
yy[0] = tmp;
if (zPend > 0) {
zPend--;
@@ -244,7 +230,26 @@ void generateMTFValues ( EState* s )
};
zPend = 0;
}
mtfv[wr] = j+1; wr++; s->mtfFreq[j+1]++;
{
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]++;
}
}
}
@@ -261,6 +266,7 @@ void generateMTFValues ( EState* s )
if (zPend < 2) break;
zPend = (zPend - 2) / 2;
};
zPend = 0;
}
mtfv[wr] = EOB; wr++; s->mtfFreq[EOB]++;
@@ -365,6 +371,18 @@ void sendMTFValues ( EState* s )
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;
@@ -381,21 +399,37 @@ void sendMTFValues ( EState* s )
--*/
for (t = 0; t < nGroups; t++) cost[t] = 0;
if (nGroups == 6) {
register UInt16 cost0, cost1, cost2, cost3, cost4, cost5;
cost0 = cost1 = cost2 = cost3 = cost4 = cost5 = 0;
for (i = gs; i <= ge; i++) {
UInt16 icv = mtfv[i];
cost0 += s->len[0][icv];
cost1 += s->len[1][icv];
cost2 += s->len[2][icv];
cost3 += s->len[3][icv];
cost4 += s->len[4][icv];
cost5 += s->len[5][icv];
}
cost[0] = cost0; cost[1] = cost1; cost[2] = cost2;
cost[3] = cost3; cost[4] = cost4; cost[5] = cost5;
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];
@@ -417,8 +451,29 @@ void sendMTFValues ( EState* s )
/*--
Increment the symbol frequencies for the selected table.
--*/
for (i = gs; i <= ge; i++)
s->rfreq[bt][ mtfv[i] ]++;
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;
}
@@ -434,8 +489,8 @@ void sendMTFValues ( EState* s )
Recompute the tables based on the accumulated frequencies.
--*/
for (t = 0; t < nGroups; t++)
hbMakeCodeLengths ( &(s->len[t][0]), &(s->rfreq[t][0]),
alphaSize, 20 );
BZ2_hbMakeCodeLengths ( &(s->len[t][0]), &(s->rfreq[t][0]),
alphaSize, 20 );
}
@@ -474,8 +529,8 @@ void sendMTFValues ( EState* s )
}
AssertH ( !(maxLen > 20), 3004 );
AssertH ( !(minLen < 1), 3005 );
hbAssignCodes ( &(s->code[t][0]), &(s->len[t][0]),
minLen, maxLen, alphaSize );
BZ2_hbAssignCodes ( &(s->code[t][0]), &(s->len[t][0]),
minLen, maxLen, alphaSize );
}
/*--- Transmit the mapping table. ---*/
@@ -536,13 +591,45 @@ void sendMTFValues ( EState* s )
if (gs >= s->nMTF) break;
ge = gs + BZ_G_SIZE - 1;
if (ge >= s->nMTF) ge = s->nMTF-1;
for (i = gs; i <= ge; i++) {
AssertH ( s->selector[selCtr] < nGroups, 3006 );
bsW ( s,
s->len [s->selector[selCtr]] [mtfv[i]],
s->code [s->selector[selCtr]] [mtfv[i]] );
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++;
}
@@ -554,7 +641,7 @@ void sendMTFValues ( EState* s )
/*---------------------------------------------------*/
void compressBlock ( EState* s, Bool is_last_block )
void BZ2_compressBlock ( EState* s, Bool is_last_block )
{
if (s->nblock > 0) {
@@ -568,14 +655,14 @@ void compressBlock ( EState* s, Bool is_last_block )
"combined CRC = 0x%8x, size = %d\n",
s->blockNo, s->blockCRC, s->combinedCRC, s->nblock );
blockSort ( s );
BZ2_blockSort ( s );
}
s->zbits = (UChar*) (&((UInt16*)s->arr2)[s->nblock]);
s->zbits = (UChar*) (&((UChar*)s->arr2)[s->nblock]);
/*-- If this is the first block, create the stream header. --*/
if (s->blockNo == 1) {
bsInitWrite ( s );
BZ2_bsInitWrite ( s );
bsPutUChar ( s, 'B' );
bsPutUChar ( s, 'Z' );
bsPutUChar ( s, 'h' );