emo/busybox
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
77f1ec1b9b
busybox/archival/bz/bzlib.c

434 lines
11 KiB
C
Raw Normal View History

bzip2: port bzip2 1.0.4 to busybox. note: bzip2 code resides in separate directory (archival/bz/*) and is covered by BSD-style license. code size: 13k
2007-10-13 09:06:03 +05:30
/*
* 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 ---*/
/*---------------------------------------------------*/
/*---------------------------------------------------*/
#ifndef BZ_NO_STDIO
static void bz_assert_fail(int errcode)
{
/* if (errcode == 1007) bb_error_msg_and_die("probably bad RAM"); */
bb_error_msg_and_die("bzip2 internal error %d", errcode);
}
#endif
/*---------------------------------------------------*/
static
void prepare_new_block(EState* s)
{
int32_t i;
s->nblock = 0;
s->numZ = 0;
s->state_out_pos = 0;
BZ_INITIALISE_CRC(s->blockCRC);
for (i = 0; i < 256; i++) s->inUse[i] = False;
s->blockNo++;
}
/*---------------------------------------------------*/
static
ALWAYS_INLINE
void init_RL(EState* s)
{
s->state_in_ch = 256;
s->state_in_len = 0;
}
static
Bool isempty_RL(EState* s)
{
if (s->state_in_ch < 256 && s->state_in_len > 0)
return False;
return True;
}
/*---------------------------------------------------*/
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 = (UChar*)s->arr2;
s->ftab = xmalloc(65537 * sizeof(uint32_t));
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;
UChar ch = (UChar)(s->state_in_ch);
for (i = 0; i < s->state_in_len; i++) {
BZ_UPDATE_CRC(s->blockCRC, ch);
}
s->inUse[s->state_in_ch] = True;
switch (s->state_in_len) {
case 1:
s->block[s->nblock] = (UChar)ch; s->nblock++;
break;
case 2:
s->block[s->nblock] = (UChar)ch; s->nblock++;
s->block[s->nblock] = (UChar)ch; s->nblock++;
break;
case 3:
s->block[s->nblock] = (UChar)ch; s->nblock++;
s->block[s->nblock] = (UChar)ch; s->nblock++;
s->block[s->nblock] = (UChar)ch; s->nblock++;
break;
default:
s->inUse[s->state_in_len-4] = True;
s->block[s->nblock] = (UChar)ch; s->nblock++;
s->block[s->nblock] = (UChar)ch; s->nblock++;
s->block[s->nblock] = (UChar)ch; s->nblock++;
s->block[s->nblock] = (UChar)ch; s->nblock++;
s->block[s->nblock] = ((UChar)(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) { \
UChar ch = (UChar)(zs->state_in_ch); \
BZ_UPDATE_CRC(zs->blockCRC, ch); \
zs->inUse[zs->state_in_ch] = True; \
zs->block[zs->nblock] = (UChar)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
Bool copy_input_until_stop(EState* s)
{
Bool progress_in = False;
//vda: cannot simplify this until avail_in_expect is removed
if (s->mode == BZ_M_RUNNING) {
/*-- fast track the common case --*/
while (1) {
/*-- block full? --*/
if (s->nblock >= s->nblockMAX) break;
/*-- no input? --*/
if (s->strm->avail_in == 0) break;
progress_in = True;
ADD_CHAR_TO_BLOCK(s, (uint32_t)(*((UChar*)(s->strm->next_in))));
s->strm->next_in++;
s->strm->avail_in--;
/*s->strm->total_in++;*/
}
} else {
/*-- general, uncommon case --*/
while (1) {
/*-- block full? --*/
if (s->nblock >= s->nblockMAX) break;
/*-- no input? --*/
if (s->strm->avail_in == 0) break;
/*-- flush/finish end? --*/
if (s->avail_in_expect == 0) break;
progress_in = True;
ADD_CHAR_TO_BLOCK(s, (uint32_t)(*((UChar*)(s->strm->next_in))));
s->strm->next_in++;
s->strm->avail_in--;
/*s->strm->total_in++;*/
s->avail_in_expect--;
}
}
return progress_in;
}
/*---------------------------------------------------*/
static
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
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
&& isempty_RL(s))
break;
prepare_new_block(s);
s->state = BZ_S_INPUT;
if (s->mode == BZ_M_FLUSHING
&& s->avail_in_expect == 0
&& isempty_RL(s))
break;
}
if (s->state == BZ_S_INPUT) {
progress_in |= copy_input_until_stop(s);
if (s->mode != BZ_M_RUNNING && s->avail_in_expect == 0) {
flush_RL(s);
BZ2_compressBlock(s, (Bool)(s->mode == BZ_M_FINISHING));
s->state = BZ_S_OUTPUT;
} else
if (s->nblock >= s->nblockMAX) {
BZ2_compressBlock(s, False);
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;
if (strm == NULL) return BZ_PARAM_ERROR;
s = strm->state;
if (s == NULL) return BZ_PARAM_ERROR;
if (s->strm != strm) return BZ_PARAM_ERROR;
preswitch:
switch (s->mode) {
case BZ_M_IDLE:
return BZ_SEQUENCE_ERROR;
case BZ_M_RUNNING:
if (action == BZ_RUN) {
progress = handle_compress(strm);
return progress ? BZ_RUN_OK : BZ_PARAM_ERROR;
}
else
if (action == BZ_FLUSH) {
s->avail_in_expect = strm->avail_in;
s->mode = BZ_M_FLUSHING;
goto preswitch;
}
else
if (action == BZ_FINISH) {
s->avail_in_expect = strm->avail_in;
s->mode = BZ_M_FINISHING;
goto preswitch;
}
else
return BZ_PARAM_ERROR;
case BZ_M_FLUSHING:
if (action != BZ_FLUSH) return BZ_SEQUENCE_ERROR;
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;
case BZ_M_FINISHING:
if (action != BZ_FINISH) return BZ_SEQUENCE_ERROR;
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;
s->mode = BZ_M_IDLE;
return BZ_STREAM_END;
}
return BZ_OK; /*--not reached--*/
}
/*---------------------------------------------------*/
static
int BZ2_bzCompressEnd(bz_stream *strm)
{
EState* s;
if (strm == NULL) return BZ_PARAM_ERROR;
s = strm->state;
if (s == NULL) return BZ_PARAM_ERROR;
if (s->strm != strm) return BZ_PARAM_ERROR;
if (s->arr1 != NULL) free(s->arr1);
if (s->arr2 != NULL) free(s->arr2);
if (s->ftab != NULL) free(s->ftab);
free(strm->state);
strm->state = NULL;
return BZ_OK;
}
/*---------------------------------------------------*/
/*--- 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 ---*/
/*-------------------------------------------------------------*/
Reference in New Issue Copy Permalink