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zlib 1.0.7

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This commit is contained in:
Mark Adler
2011-09-09 23:17:33 -07:00
parent ebd3c2c0e7
commit 7850e4e406
58 changed files with 4608 additions and 519 deletions
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167
deflate.c
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@@ -36,8 +36,8 @@
*
* REFERENCES
*
* Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
* Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
* Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
* Available in ftp://ds.internic.net/rfc/rfc1951.txt
*
* A description of the Rabin and Karp algorithm is given in the book
* "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
@@ -47,10 +47,12 @@
*
*/
/* @(#) $Id$ */
#include "deflate.h"
char deflate_copyright[] = " deflate 1.0.5 Copyright 1995-1998 Jean-loup Gailly ";
const char deflate_copyright[] =
" deflate 1.0.7 Copyright 1995-1998 Jean-loup Gailly ";
/*
If you use the zlib library in a product, an acknowledgment is welcome
in the documentation of your product. If for some reason you cannot
@@ -76,12 +78,14 @@ local block_state deflate_stored OF((deflate_state *s, int flush));
local block_state deflate_fast OF((deflate_state *s, int flush));
local block_state deflate_slow OF((deflate_state *s, int flush));
local void lm_init OF((deflate_state *s));
local uInt longest_match OF((deflate_state *s, IPos cur_match));
local void putShortMSB OF((deflate_state *s, uInt b));
local void flush_pending OF((z_streamp strm));
local int read_buf OF((z_streamp strm, charf *buf, unsigned size));
#ifdef ASMV
void match_init OF((void)); /* asm code initialization */
uInt longest_match OF((deflate_state *s, IPos cur_match));
#else
local uInt longest_match OF((deflate_state *s, IPos cur_match));
#endif
#ifdef DEBUG
@@ -119,7 +123,7 @@ typedef struct config_s {
compress_func func;
} config;
local config configuration_table[10] = {
local const config configuration_table[10] = {
/* good lazy nice chain */
/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */
/* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */
@@ -174,7 +178,7 @@ struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
zmemzero((charf *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
/* ========================================================================= */
int deflateInit_(strm, level, version, stream_size)
int EXPORT deflateInit_(strm, level, version, stream_size)
z_streamp strm;
int level;
const char *version;
@@ -186,7 +190,7 @@ int deflateInit_(strm, level, version, stream_size)
}
/* ========================================================================= */
int deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
int EXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
version, stream_size)
z_streamp strm;
int level;
@@ -199,13 +203,14 @@ int deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
{
deflate_state *s;
int noheader = 0;
static const char* my_version = ZLIB_VERSION;
ushf *overlay;
/* We overlay pending_buf and d_buf+l_buf. This works since the average
* output size for (length,distance) codes is <= 24 bits.
*/
if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
if (version == Z_NULL || version[0] != my_version[0] ||
stream_size != sizeof(z_stream)) {
return Z_VERSION_ERROR;
}
@@ -252,6 +257,7 @@ int deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
s->pending_buf = (uchf *) overlay;
s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
s->pending_buf == Z_NULL) {
@@ -270,7 +276,7 @@ int deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
}
/* ========================================================================= */
int deflateSetDictionary (strm, dictionary, dictLength)
int EXPORT deflateSetDictionary (strm, dictionary, dictLength)
z_streamp strm;
const Bytef *dictionary;
uInt dictLength;
@@ -289,7 +295,9 @@ int deflateSetDictionary (strm, dictionary, dictLength)
if (length < MIN_MATCH) return Z_OK;
if (length > MAX_DIST(s)) {
length = MAX_DIST(s);
dictionary += dictLength - length;
#ifndef USE_DICT_HEAD
dictionary += dictLength - length; /* use the tail of the dictionary */
#endif
}
zmemcpy((charf *)s->window, dictionary, length);
s->strstart = length;
@@ -309,7 +317,7 @@ int deflateSetDictionary (strm, dictionary, dictLength)
}
/* ========================================================================= */
int deflateReset (strm)
int EXPORT deflateReset (strm)
z_streamp strm;
{
deflate_state *s;
@@ -339,7 +347,7 @@ int deflateReset (strm)
}
/* ========================================================================= */
int deflateParams(strm, level, strategy)
int EXPORT deflateParams(strm, level, strategy)
z_streamp strm;
int level;
int strategy;
@@ -413,7 +421,7 @@ local void flush_pending(strm)
}
/* ========================================================================= */
int deflate (strm, flush)
int EXPORT deflate (strm, flush)
z_streamp strm;
int flush;
{
@@ -547,42 +555,85 @@ int deflate (strm, flush)
}
/* ========================================================================= */
int deflateEnd (strm)
int EXPORT deflateEnd (strm)
z_streamp strm;
{
int status;
if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
status = strm->state->status;
if (status != INIT_STATE && status != BUSY_STATE &&
status != FINISH_STATE) {
return Z_STREAM_ERROR;
}
/* Deallocate in reverse order of allocations: */
TRY_FREE(strm, strm->state->pending_buf);
TRY_FREE(strm, strm->state->head);
TRY_FREE(strm, strm->state->prev);
TRY_FREE(strm, strm->state->window);
status = strm->state->status;
ZFREE(strm, strm->state);
strm->state = Z_NULL;
return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
}
/* ========================================================================= */
int deflateCopy (dest, source)
/* =========================================================================
* Copy the source state to the destination state.
* To simplify the source, this is not supported for 16-bit MSDOS (which
* doesn't have enough memory anyway to duplicate compression states).
*/
int EXPORT deflateCopy (dest, source)
z_streamp dest;
z_streamp source;
{
if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {
#ifdef MAXSEG_64K
return Z_STREAM_ERROR;
#else
deflate_state *ds;
deflate_state *ss;
ushf *overlay;
ss = source->state;
if (source == Z_NULL || dest == Z_NULL || ss == Z_NULL) {
return Z_STREAM_ERROR;
}
*dest = *source;
return Z_STREAM_ERROR; /* to be implemented */
#if 0
dest->state = (struct internal_state FAR *)
(*dest->zalloc)(1, sizeof(deflate_state));
if (dest->state == Z_NULL) return Z_MEM_ERROR;
*(dest->state) = *(source->state);
ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
if (ds == Z_NULL) return Z_MEM_ERROR;
dest->state = (struct internal_state FAR *) ds;
*ds = *ss;
ds->strm = dest;
ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
ds->pending_buf = (uchf *) overlay;
if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
ds->pending_buf == Z_NULL) {
deflateEnd (dest);
return Z_MEM_ERROR;
}
/* following zmemcpy do not work for 16-bit MSDOS */
zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
ds->l_desc.dyn_tree = ds->dyn_ltree;
ds->d_desc.dyn_tree = ds->dyn_dtree;
ds->bl_desc.dyn_tree = ds->bl_tree;
return Z_OK;
#endif
}
@@ -815,7 +866,7 @@ local void check_match(s, start, match, length)
} while (--length != 0);
z_error("invalid match");
}
if (verbose > 1) {
if (z_verbose > 1) {
fprintf(stderr,"\\[%d,%d]", start-match, length);
do { putc(s->window[start++], stderr); } while (--length != 0);
}
@@ -864,29 +915,30 @@ local void fill_window(s)
(unsigned)wsize);
s->match_start -= wsize;
s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
s->block_start -= (long) wsize;
/* Slide the hash table (could be avoided with 32 bit values
at the expense of memory usage):
at the expense of memory usage). We slide even when level == 0
to keep the hash table consistent if we switch back to level > 0
later. (Using level 0 permanently is not an optimal usage of
zlib, so we don't care about this pathological case.)
*/
n = s->hash_size;
p = &s->head[n];
do {
m = *--p;
*p = (Pos)(m >= wsize ? m-wsize : NIL);
} while (--n);
n = wsize;
p = &s->prev[n];
do {
m = *--p;
*p = (Pos)(m >= wsize ? m-wsize : NIL);
/* If n is not on any hash chain, prev[n] is garbage but
* its value will never be used.
*/
} while (--n);
n = s->hash_size;
p = &s->head[n];
do {
m = *--p;
*p = (Pos)(m >= wsize ? m-wsize : NIL);
} while (--n);
n = wsize;
p = &s->prev[n];
do {
m = *--p;
*p = (Pos)(m >= wsize ? m-wsize : NIL);
/* If n is not on any hash chain, prev[n] is garbage but
* its value will never be used.
*/
} while (--n);
more += wsize;
}
if (s->strm->avail_in == 0) return;
@@ -950,12 +1002,24 @@ local void fill_window(s)
* This function does not insert new strings in the dictionary since
* uncompressible data is probably not useful. This function is used
* only for the level=0 compression option.
* NOTE: this function should be optimized to avoid extra copying.
* NOTE: this function should be optimized to avoid extra copying from
* window to pending_buf.
*/
local block_state deflate_stored(s, flush)
deflate_state *s;
int flush;
{
/* Stored blocks are limited to 0xffff bytes, pending_buf is limited
* to pending_buf_size, and each stored block has a 5 byte header:
*/
ulg max_block_size = 0xffff;
ulg max_start;
if (max_block_size > s->pending_buf_size - 5) {
max_block_size = s->pending_buf_size - 5;
}
/* Copy as much as possible from input to output: */
for (;;) {
/* Fill the window as much as possible: */
if (s->lookahead <= 1) {
@@ -973,14 +1037,17 @@ local block_state deflate_stored(s, flush)
s->strstart += s->lookahead;
s->lookahead = 0;
/* Stored blocks are limited to 0xffff bytes: */
if (s->strstart == 0 || s->strstart > 0xfffe) {
/* Emit a stored block if pending_buf will be full: */
max_start = s->block_start + max_block_size;
if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
/* strstart == 0 is possible when wraparound on 16-bit machine */
s->lookahead = s->strstart - 0xffff;
s->strstart = 0xffff;
s->lookahead = (uInt)(s->strstart - max_start);
s->strstart = (uInt)max_start;
FLUSH_BLOCK(s, 0);
}
/* Emit a stored block if it is large enough: */
/* Flush if we may have to slide, otherwise block_start may become
* negative and the data will be gone:
*/
if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
FLUSH_BLOCK(s, 0);
}