hush/archival/bz/bzlib.c
Denis Vlasenko 31acd1ba0a bzip2: more of code shrink
compressStream                                       503     473     -30
BZ2_bzCompress                                        78       -     -78
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 0/1 up/down: 0/-108)           Total: -108 bytes
   text    data     bss     dec     hex filename
 676300    2538   12104  690942   a8afe busybox_old
 676192    2538   12104  690834   a8a92 busybox_unstripped
2007-10-17 10:14:11 +00:00

430 lines
11 KiB
C

/*
* 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.
*/
/*-------------------------------------------------------------*/
/*--- Library top-level functions. ---*/
/*--- bzlib.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 -- made zero-length BZ_FLUSH work correctly in bzCompress().
* fixed bzWrite/bzRead to ignore zero-length requests.
* fixed bzread to correctly handle read requests after EOF.
* wrong parameter order in call to bzDecompressInit in
* bzBuffToBuffDecompress. Fixed.
*/
/* #include "bzlib_private.h" */
/*---------------------------------------------------*/
/*--- Compression stuff ---*/
/*---------------------------------------------------*/
/*---------------------------------------------------*/
#if BZ_LIGHT_DEBUG
static
void bz_assert_fail(int errcode)
{
/* if (errcode == 1007) bb_error_msg_and_die("probably bad RAM"); */
bb_error_msg_and_die("internal error %d", errcode);
}
#endif
/*---------------------------------------------------*/
static
void prepare_new_block(EState* s)
{
int i;
s->nblock = 0;
s->numZ = 0;
s->state_out_pos = 0;
BZ_INITIALISE_CRC(s->blockCRC);
/* inlined memset would be nice to have here */
for (i = 0; i < 256; i++)
s->inUse[i] = 0;
s->blockNo++;
}
/*---------------------------------------------------*/
static
ALWAYS_INLINE
void init_RL(EState* s)
{
s->state_in_ch = 256;
s->state_in_len = 0;
}
static
int isempty_RL(EState* s)
{
return (s->state_in_ch >= 256 || s->state_in_len <= 0);
}
/*---------------------------------------------------*/
static
void BZ2_bzCompressInit(bz_stream *strm, int blockSize100k)
{
int32_t n;
EState* s;
s = xzalloc(sizeof(EState));
s->strm = strm;
n = 100000 * blockSize100k;
s->arr1 = xmalloc(n * sizeof(uint32_t));
s->mtfv = (uint16_t*)s->arr1;
s->ptr = (uint32_t*)s->arr1;
s->arr2 = xmalloc((n + BZ_N_OVERSHOOT) * sizeof(uint32_t));
s->block = (uint8_t*)s->arr2;
s->ftab = xmalloc(65537 * sizeof(uint32_t));
s->crc32table = crc32_filltable(NULL, 1);
s->state = BZ_S_INPUT;
s->mode = BZ_M_RUNNING;
s->blockSize100k = blockSize100k;
s->nblockMAX = n - 19;
strm->state = s;
/*strm->total_in = 0;*/
strm->total_out = 0;
init_RL(s);
prepare_new_block(s);
}
/*---------------------------------------------------*/
static
void add_pair_to_block(EState* s)
{
int32_t i;
uint8_t ch = (uint8_t)(s->state_in_ch);
for (i = 0; i < s->state_in_len; i++) {
BZ_UPDATE_CRC(s, s->blockCRC, ch);
}
s->inUse[s->state_in_ch] = 1;
switch (s->state_in_len) {
case 3:
s->block[s->nblock] = (uint8_t)ch; s->nblock++;
/* fall through */
case 2:
s->block[s->nblock] = (uint8_t)ch; s->nblock++;
/* fall through */
case 1:
s->block[s->nblock] = (uint8_t)ch; s->nblock++;
break;
default:
s->inUse[s->state_in_len - 4] = 1;
s->block[s->nblock] = (uint8_t)ch; s->nblock++;
s->block[s->nblock] = (uint8_t)ch; s->nblock++;
s->block[s->nblock] = (uint8_t)ch; s->nblock++;
s->block[s->nblock] = (uint8_t)ch; s->nblock++;
s->block[s->nblock] = (uint8_t)(s->state_in_len - 4);
s->nblock++;
break;
}
}
/*---------------------------------------------------*/
static
void flush_RL(EState* s)
{
if (s->state_in_ch < 256) add_pair_to_block(s);
init_RL(s);
}
/*---------------------------------------------------*/
#define ADD_CHAR_TO_BLOCK(zs, zchh0) \
{ \
uint32_t zchh = (uint32_t)(zchh0); \
/*-- fast track the common case --*/ \
if (zchh != zs->state_in_ch && zs->state_in_len == 1) { \
uint8_t ch = (uint8_t)(zs->state_in_ch); \
BZ_UPDATE_CRC(zs, zs->blockCRC, ch); \
zs->inUse[zs->state_in_ch] = 1; \
zs->block[zs->nblock] = (uint8_t)ch; \
zs->nblock++; \
zs->state_in_ch = zchh; \
} \
else \
/*-- general, uncommon cases --*/ \
if (zchh != zs->state_in_ch || zs->state_in_len == 255) { \
if (zs->state_in_ch < 256) \
add_pair_to_block(zs); \
zs->state_in_ch = zchh; \
zs->state_in_len = 1; \
} else { \
zs->state_in_len++; \
} \
}
/*---------------------------------------------------*/
static
void /*Bool*/ copy_input_until_stop(EState* s)
{
/*Bool progress_in = False;*/
#ifdef SAME_CODE_AS_BELOW
if (s->mode == BZ_M_RUNNING) {
/*-- fast track the common case --*/
while (1) {
/*-- no input? --*/
if (s->strm->avail_in == 0) break;
/*-- block full? --*/
if (s->nblock >= s->nblockMAX) break;
/*progress_in = True;*/
ADD_CHAR_TO_BLOCK(s, (uint32_t)(*(uint8_t*)(s->strm->next_in)));
s->strm->next_in++;
s->strm->avail_in--;
/*s->strm->total_in++;*/
}
} else
#endif
{
/*-- general, uncommon case --*/
while (1) {
/*-- no input? --*/
if (s->strm->avail_in == 0) break;
/*-- block full? --*/
if (s->nblock >= s->nblockMAX) break;
//# /*-- flush/finish end? --*/
//# if (s->avail_in_expect == 0) break;
/*progress_in = True;*/
ADD_CHAR_TO_BLOCK(s, *(uint8_t*)(s->strm->next_in));
s->strm->next_in++;
s->strm->avail_in--;
/*s->strm->total_in++;*/
//# s->avail_in_expect--;
}
}
/*return progress_in;*/
}
/*---------------------------------------------------*/
static
void /*Bool*/ copy_output_until_stop(EState* s)
{
/*Bool progress_out = False;*/
while (1) {
/*-- no output space? --*/
if (s->strm->avail_out == 0) break;
/*-- block done? --*/
if (s->state_out_pos >= s->numZ) break;
/*progress_out = True;*/
*(s->strm->next_out) = s->zbits[s->state_out_pos];
s->state_out_pos++;
s->strm->avail_out--;
s->strm->next_out++;
s->strm->total_out++;
}
/*return progress_out;*/
}
/*---------------------------------------------------*/
static
void /*Bool*/ handle_compress(bz_stream *strm)
{
/*Bool progress_in = False;*/
/*Bool progress_out = False;*/
EState* s = strm->state;
while (1) {
if (s->state == BZ_S_OUTPUT) {
/*progress_out |=*/ copy_output_until_stop(s);
if (s->state_out_pos < s->numZ) break;
if (s->mode == BZ_M_FINISHING
//# && s->avail_in_expect == 0
&& s->strm->avail_in == 0
&& isempty_RL(s))
break;
prepare_new_block(s);
s->state = BZ_S_INPUT;
#ifdef FLUSH_IS_UNUSED
if (s->mode == BZ_M_FLUSHING
&& s->avail_in_expect == 0
&& isempty_RL(s))
break;
#endif
}
if (s->state == BZ_S_INPUT) {
/*progress_in |=*/ copy_input_until_stop(s);
//#if (s->mode != BZ_M_RUNNING && s->avail_in_expect == 0) {
if (s->mode != BZ_M_RUNNING && s->strm->avail_in == 0) {
flush_RL(s);
BZ2_compressBlock(s, (s->mode == BZ_M_FINISHING));
s->state = BZ_S_OUTPUT;
} else
if (s->nblock >= s->nblockMAX) {
BZ2_compressBlock(s, 0);
s->state = BZ_S_OUTPUT;
} else
if (s->strm->avail_in == 0) {
break;
}
}
}
/*return progress_in || progress_out;*/
}
/*---------------------------------------------------*/
static
int BZ2_bzCompress(bz_stream *strm, int action)
{
/*Bool progress;*/
EState* s;
s = strm->state;
switch (s->mode) {
case BZ_M_RUNNING:
if (action == BZ_RUN) {
/*progress =*/ handle_compress(strm);
/*return progress ? BZ_RUN_OK : BZ_PARAM_ERROR;*/
return BZ_RUN_OK;
}
#ifdef FLUSH_IS_UNUSED
else
if (action == BZ_FLUSH) {
//#s->avail_in_expect = strm->avail_in;
s->mode = BZ_M_FLUSHING;
goto case_BZ_M_FLUSHING;
}
#endif
else
/*if (action == BZ_FINISH)*/ {
//#s->avail_in_expect = strm->avail_in;
s->mode = BZ_M_FINISHING;
goto case_BZ_M_FINISHING;
}
#ifdef FLUSH_IS_UNUSED
case_BZ_M_FLUSHING:
case BZ_M_FLUSHING:
/*if (s->avail_in_expect != s->strm->avail_in)
return BZ_SEQUENCE_ERROR;*/
/*progress =*/ handle_compress(strm);
if (s->avail_in_expect > 0 || !isempty_RL(s) || s->state_out_pos < s->numZ)
return BZ_FLUSH_OK;
s->mode = BZ_M_RUNNING;
return BZ_RUN_OK;
#endif
case_BZ_M_FINISHING:
/*case BZ_M_FINISHING:*/
default:
/*if (s->avail_in_expect != s->strm->avail_in)
return BZ_SEQUENCE_ERROR;*/
/*progress =*/ handle_compress(strm);
/*if (!progress) return BZ_SEQUENCE_ERROR;*/
//#if (s->avail_in_expect > 0 || !isempty_RL(s) || s->state_out_pos < s->numZ)
//# return BZ_FINISH_OK;
if (s->strm->avail_in > 0 || !isempty_RL(s) || s->state_out_pos < s->numZ)
return BZ_FINISH_OK;
/*s->mode = BZ_M_IDLE;*/
return BZ_STREAM_END;
}
/* return BZ_OK; --not reached--*/
}
/*---------------------------------------------------*/
#if ENABLE_FEATURE_CLEAN_UP
static
void BZ2_bzCompressEnd(bz_stream *strm)
{
EState* s;
s = strm->state;
free(s->arr1);
free(s->arr2);
free(s->ftab);
free(s->crc32table);
free(strm->state);
}
#endif
/*---------------------------------------------------*/
/*--- Misc convenience stuff ---*/
/*---------------------------------------------------*/
/*---------------------------------------------------*/
#ifdef EXAMPLE_CODE_FOR_MEM_TO_MEM_COMPRESSION
static
int BZ2_bzBuffToBuffCompress(char* dest,
unsigned int* destLen,
char* source,
unsigned int sourceLen,
int blockSize100k)
{
bz_stream strm;
int ret;
if (dest == NULL || destLen == NULL ||
source == NULL ||
blockSize100k < 1 || blockSize100k > 9)
return BZ_PARAM_ERROR;
BZ2_bzCompressInit(&strm, blockSize100k);
strm.next_in = source;
strm.next_out = dest;
strm.avail_in = sourceLen;
strm.avail_out = *destLen;
ret = BZ2_bzCompress(&strm, BZ_FINISH);
if (ret == BZ_FINISH_OK) goto output_overflow;
if (ret != BZ_STREAM_END) goto errhandler;
/* normal termination */
*destLen -= strm.avail_out;
BZ2_bzCompressEnd(&strm);
return BZ_OK;
output_overflow:
BZ2_bzCompressEnd(&strm);
return BZ_OUTBUFF_FULL;
errhandler:
BZ2_bzCompressEnd(&strm);
return ret;
}
#endif
/*-------------------------------------------------------------*/
/*--- end bzlib.c ---*/
/*-------------------------------------------------------------*/