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zlib 1.2.0.1

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This commit is contained in:
Mark Adler
2011-09-09 23:21:57 -07:00
parent 7c2a874e50
commit 13a294f044
71 changed files with 10250 additions and 3923 deletions
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273
deflate.c
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@@ -1,6 +1,6 @@
/* deflate.c -- compress data using the deflation algorithm
* Copyright (C) 1995-2003 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/*
@@ -52,7 +52,7 @@
#include "deflate.h"
const char deflate_copyright[] =
" deflate 1.2.0 Copyright 1995-2003 Jean-loup Gailly ";
" deflate 1.2.0.1 Copyright 1995-2003 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
@@ -76,17 +76,22 @@ typedef block_state (*compress_func) OF((deflate_state *s, int flush));
local void fill_window OF((deflate_state *s));
local block_state deflate_stored OF((deflate_state *s, int flush));
local block_state deflate_fast OF((deflate_state *s, int flush));
#ifndef FASTEST
local block_state deflate_slow OF((deflate_state *s, int flush));
#endif
local void lm_init OF((deflate_state *s));
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, Bytef *buf, unsigned size));
#ifndef FASTEST
#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
#endif
local uInt longest_match_fast OF((deflate_state *s, IPos cur_match));
#ifdef DEBUG
local void check_match OF((deflate_state *s, IPos start, IPos match,
@@ -123,6 +128,12 @@ typedef struct config_s {
compress_func func;
} config;
#ifdef FASTEST
local const config configuration_table[2] = {
/* 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 */
#else
local const config configuration_table[10] = {
/* good lazy nice chain */
/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */
@@ -136,6 +147,7 @@ local const config configuration_table[10] = {
/* 7 */ {8, 32, 128, 256, deflate_slow},
/* 8 */ {32, 128, 258, 1024, deflate_slow},
/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */
#endif
/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
* For deflate_fast() (levels <= 3) good is ignored and lazy has a different
@@ -194,13 +206,13 @@ int ZEXPORT deflateInit_(strm, level, version, stream_size)
int stream_size;
{
return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
Z_DEFAULT_STRATEGY, version, stream_size);
Z_DEFAULT_STRATEGY, version, stream_size);
/* To do: ignore strm->next_in if we use it as window */
}
/* ========================================================================= */
int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
version, stream_size)
version, stream_size)
z_streamp strm;
int level;
int method;
@@ -221,20 +233,21 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
if (version == Z_NULL || version[0] != my_version[0] ||
stream_size != sizeof(z_stream)) {
return Z_VERSION_ERROR;
return Z_VERSION_ERROR;
}
if (strm == Z_NULL) return Z_STREAM_ERROR;
strm->msg = Z_NULL;
if (strm->zalloc == Z_NULL) {
strm->zalloc = zcalloc;
strm->opaque = (voidpf)0;
strm->zalloc = zcalloc;
strm->opaque = (voidpf)0;
}
if (strm->zfree == Z_NULL) strm->zfree = zcfree;
if (level == Z_DEFAULT_COMPRESSION) level = 6;
#ifdef FASTEST
level = 1;
if (level != 0) level = 1;
#else
if (level == Z_DEFAULT_COMPRESSION) level = 6;
#endif
if (windowBits < 0) { /* undocumented feature: suppress zlib header */
@@ -243,7 +256,7 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
}
if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
windowBits < 9 || windowBits > 15 || level < 0 || level > 9 ||
strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
strategy < 0 || strategy > Z_RLE) {
return Z_STREAM_ERROR;
}
s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
@@ -309,9 +322,9 @@ int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
if (length < MIN_MATCH) return Z_OK;
if (length > MAX_DIST(s)) {
length = MAX_DIST(s);
length = MAX_DIST(s);
#ifndef USE_DICT_HEAD
dictionary += dictLength - length; /* use the tail of the dictionary */
dictionary += dictLength - length; /* use the tail of the dictionary */
#endif
}
zmemcpy(s->window, dictionary, length);
@@ -325,7 +338,7 @@ int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
s->ins_h = s->window[0];
UPDATE_HASH(s, s->ins_h, s->window[1]);
for (n = 0; n <= length - MIN_MATCH; n++) {
INSERT_STRING(s, n, hash_head);
INSERT_STRING(s, n, hash_head);
}
if (hash_head) hash_head = 0; /* to make compiler happy */
return Z_OK;
@@ -336,7 +349,7 @@ int ZEXPORT deflateReset (strm)
z_streamp strm;
{
deflate_state *s;
if (strm == Z_NULL || strm->state == Z_NULL ||
strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
@@ -374,24 +387,26 @@ int ZEXPORT deflateParams(strm, level, strategy)
if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
s = strm->state;
if (level == Z_DEFAULT_COMPRESSION) {
level = 6;
}
if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
return Z_STREAM_ERROR;
#ifdef FASTEST
if (level != 0) level = 1;
#else
if (level == Z_DEFAULT_COMPRESSION) level = 6;
#endif
if (level < 0 || level > 9 || strategy < 0 || strategy > Z_RLE) {
return Z_STREAM_ERROR;
}
func = configuration_table[s->level].func;
if (func != configuration_table[level].func && strm->total_in != 0) {
/* Flush the last buffer: */
err = deflate(strm, Z_PARTIAL_FLUSH);
/* Flush the last buffer: */
err = deflate(strm, Z_PARTIAL_FLUSH);
}
if (s->level != level) {
s->level = level;
s->max_lazy_match = configuration_table[level].max_lazy;
s->good_match = configuration_table[level].good_length;
s->nice_match = configuration_table[level].nice_length;
s->max_chain_length = configuration_table[level].max_chain;
s->level = level;
s->max_lazy_match = configuration_table[level].max_lazy;
s->good_match = configuration_table[level].good_length;
s->nice_match = configuration_table[level].nice_length;
s->max_chain_length = configuration_table[level].max_chain;
}
s->strategy = strategy;
return err;
@@ -449,7 +464,7 @@ local void putShortMSB (s, b)
{
put_byte(s, (Byte)(b >> 8));
put_byte(s, (Byte)(b & 0xff));
}
}
/* =========================================================================
* Flush as much pending output as possible. All deflate() output goes
@@ -485,14 +500,14 @@ int ZEXPORT deflate (strm, flush)
deflate_state *s;
if (strm == Z_NULL || strm->state == Z_NULL ||
flush > Z_FINISH || flush < 0) {
flush > Z_FINISH || flush < 0) {
return Z_STREAM_ERROR;
}
s = strm->state;
if (strm->next_out == Z_NULL ||
(strm->next_in == Z_NULL && strm->avail_in != 0) ||
(s->status == FINISH_STATE && flush != Z_FINISH)) {
(s->status == FINISH_STATE && flush != Z_FINISH)) {
ERR_RETURN(strm, Z_STREAM_ERROR);
}
if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
@@ -509,40 +524,40 @@ int ZEXPORT deflate (strm, flush)
if (level_flags > 3) level_flags = 3;
header |= (level_flags << 6);
if (s->strstart != 0) header |= PRESET_DICT;
if (s->strstart != 0) header |= PRESET_DICT;
header += 31 - (header % 31);
s->status = BUSY_STATE;
putShortMSB(s, header);
/* Save the adler32 of the preset dictionary: */
if (s->strstart != 0) {
putShortMSB(s, (uInt)(strm->adler >> 16));
putShortMSB(s, (uInt)(strm->adler & 0xffff));
}
strm->adler = 1L;
/* Save the adler32 of the preset dictionary: */
if (s->strstart != 0) {
putShortMSB(s, (uInt)(strm->adler >> 16));
putShortMSB(s, (uInt)(strm->adler & 0xffff));
}
strm->adler = 1L;
}
/* Flush as much pending output as possible */
if (s->pending != 0) {
flush_pending(strm);
if (strm->avail_out == 0) {
/* Since avail_out is 0, deflate will be called again with
* more output space, but possibly with both pending and
* avail_in equal to zero. There won't be anything to do,
* but this is not an error situation so make sure we
* return OK instead of BUF_ERROR at next call of deflate:
/* Since avail_out is 0, deflate will be called again with
* more output space, but possibly with both pending and
* avail_in equal to zero. There won't be anything to do,
* but this is not an error situation so make sure we
* return OK instead of BUF_ERROR at next call of deflate:
*/
s->last_flush = -1;
return Z_OK;
}
s->last_flush = -1;
return Z_OK;
}
/* Make sure there is something to do and avoid duplicate consecutive
* flushes. For repeated and useless calls with Z_FINISH, we keep
* returning Z_STREAM_END instead of Z_BUFF_ERROR.
* returning Z_STREAM_END instead of Z_BUF_ERROR.
*/
} else if (strm->avail_in == 0 && flush <= old_flush &&
flush != Z_FINISH) {
flush != Z_FINISH) {
ERR_RETURN(strm, Z_BUF_ERROR);
}
@@ -557,24 +572,24 @@ int ZEXPORT deflate (strm, flush)
(flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
block_state bstate;
bstate = (*(configuration_table[s->level].func))(s, flush);
bstate = (*(configuration_table[s->level].func))(s, flush);
if (bstate == finish_started || bstate == finish_done) {
s->status = FINISH_STATE;
}
if (bstate == need_more || bstate == finish_started) {
if (strm->avail_out == 0) {
s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
}
return Z_OK;
/* If flush != Z_NO_FLUSH && avail_out == 0, the next call
* of deflate should use the same flush parameter to make sure
* that the flush is complete. So we don't have to output an
* empty block here, this will be done at next call. This also
* ensures that for a very small output buffer, we emit at most
* one empty block.
*/
}
if (strm->avail_out == 0) {
s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
}
return Z_OK;
/* If flush != Z_NO_FLUSH && avail_out == 0, the next call
* of deflate should use the same flush parameter to make sure
* that the flush is complete. So we don't have to output an
* empty block here, this will be done at next call. This also
* ensures that for a very small output buffer, we emit at most
* one empty block.
*/
}
if (bstate == block_done) {
if (flush == Z_PARTIAL_FLUSH) {
_tr_align(s);
@@ -588,10 +603,10 @@ int ZEXPORT deflate (strm, flush)
}
}
flush_pending(strm);
if (strm->avail_out == 0) {
s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
return Z_OK;
}
if (strm->avail_out == 0) {
s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
return Z_OK;
}
}
}
Assert(strm->avail_out > 0, "bug2");
@@ -620,7 +635,7 @@ int ZEXPORT deflateEnd (strm)
status = strm->state->status;
if (status != INIT_STATE && status != BUSY_STATE &&
status != FINISH_STATE) {
status != FINISH_STATE) {
return Z_STREAM_ERROR;
}
@@ -693,7 +708,7 @@ int ZEXPORT deflateCopy (dest, source)
ds->bl_desc.dyn_tree = ds->bl_tree;
return Z_OK;
#endif
#endif /* MAXSEG_64K */
}
/* ===========================================================================
@@ -753,6 +768,7 @@ local void lm_init (s)
#endif
}
#ifndef FASTEST
/* ===========================================================================
* Set match_start to the longest match starting at the given string and
* return its length. Matches shorter or equal to prev_length are discarded,
@@ -766,7 +782,6 @@ local void lm_init (s)
/* For 80x86 and 680x0, an optimized version will be provided in match.asm or
* match.S. The code will be functionally equivalent.
*/
#ifndef FASTEST
local uInt longest_match(s, cur_match)
deflate_state *s;
IPos cur_match; /* current match */
@@ -904,12 +919,13 @@ local uInt longest_match(s, cur_match)
if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
return s->lookahead;
}
#endif /* ASMV */
#endif /* FASTEST */
#else /* FASTEST */
/* ---------------------------------------------------------------------------
* Optimized version for level == 1 only
* Optimized version for level == 1 or strategy == Z_RLE only
*/
local uInt longest_match(s, cur_match)
local uInt longest_match_fast(s, cur_match)
deflate_state *s;
IPos cur_match; /* current match */
{
@@ -947,10 +963,10 @@ local uInt longest_match(s, cur_match)
*/
do {
} while (*++scan == *++match && *++scan == *++match &&
*++scan == *++match && *++scan == *++match &&
*++scan == *++match && *++scan == *++match &&
*++scan == *++match && *++scan == *++match &&
scan < strend);
*++scan == *++match && *++scan == *++match &&
*++scan == *++match && *++scan == *++match &&
*++scan == *++match && *++scan == *++match &&
scan < strend);
Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
@@ -961,8 +977,6 @@ local uInt longest_match(s, cur_match)
s->match_start = cur_match;
return len <= s->lookahead ? len : s->lookahead;
}
#endif /* FASTEST */
#endif /* ASMV */
#ifdef DEBUG
/* ===========================================================================
@@ -977,10 +991,10 @@ local void check_match(s, start, match, length)
if (zmemcmp(s->window + match,
s->window + start, length) != EQUAL) {
fprintf(stderr, " start %u, match %u, length %d\n",
start, match, length);
start, match, length);
do {
fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
} while (--length != 0);
fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
} while (--length != 0);
z_error("invalid match");
}
if (z_verbose > 1) {
@@ -990,7 +1004,7 @@ local void check_match(s, start, match, length)
}
#else
# define check_match(s, start, match, length)
#endif
#endif /* DEBUG */
/* ===========================================================================
* Fill the window when the lookahead becomes insufficient.
@@ -1039,23 +1053,23 @@ local void fill_window(s)
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 = s->hash_size;
p = &s->head[n];
do {
m = *--p;
*p = (Pos)(m >= wsize ? m-wsize : NIL);
} while (--n);
n = wsize;
n = wsize;
#ifndef FASTEST
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);
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);
#endif
more += wsize;
}
@@ -1100,8 +1114,8 @@ local void fill_window(s)
_tr_flush_block(s, (s->block_start >= 0L ? \
(charf *)&s->window[(unsigned)s->block_start] : \
(charf *)Z_NULL), \
(ulg)((long)s->strstart - s->block_start), \
(eof)); \
(ulg)((long)s->strstart - s->block_start), \
(eof)); \
s->block_start = s->strstart; \
flush_pending(s->strm); \
Tracev((stderr,"[FLUSH]")); \
@@ -1142,32 +1156,32 @@ local block_state deflate_stored(s, flush)
if (s->lookahead <= 1) {
Assert(s->strstart < s->w_size+MAX_DIST(s) ||
s->block_start >= (long)s->w_size, "slide too late");
s->block_start >= (long)s->w_size, "slide too late");
fill_window(s);
if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
if (s->lookahead == 0) break; /* flush the current block */
}
Assert(s->block_start >= 0L, "block gone");
Assert(s->block_start >= 0L, "block gone");
s->strstart += s->lookahead;
s->lookahead = 0;
s->strstart += s->lookahead;
s->lookahead = 0;
/* Emit a stored block if pending_buf will be full: */
max_start = s->block_start + max_block_size;
/* 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 = (uInt)(s->strstart - max_start);
s->strstart = (uInt)max_start;
/* strstart == 0 is possible when wraparound on 16-bit machine */
s->lookahead = (uInt)(s->strstart - max_start);
s->strstart = (uInt)max_start;
FLUSH_BLOCK(s, 0);
}
/* Flush if we may have to slide, otherwise block_start may become
}
/* 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);
}
}
}
FLUSH_BLOCK(s, flush == Z_FINISH);
return flush == Z_FINISH ? finish_done : block_done;
@@ -1196,8 +1210,8 @@ local block_state deflate_fast(s, flush)
if (s->lookahead < MIN_LOOKAHEAD) {
fill_window(s);
if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
return need_more;
}
return need_more;
}
if (s->lookahead == 0) break; /* flush the current block */
}
@@ -1216,10 +1230,19 @@ local block_state deflate_fast(s, flush)
* of window index 0 (in particular we have to avoid a match
* of the string with itself at the start of the input file).
*/
if (s->strategy != Z_HUFFMAN_ONLY) {
s->match_length = longest_match (s, hash_head);
#ifdef FASTEST
if ((s->strategy < Z_HUFFMAN_ONLY) ||
(s->strategy == Z_RLE && s->strstart - hash_head == 1)) {
s->match_length = longest_match_fast (s, hash_head);
}
/* longest_match() sets match_start */
#else
if (s->strategy < Z_HUFFMAN_ONLY) {
s->match_length = longest_match (s, hash_head);
} else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) {
s->match_length = longest_match_fast (s, hash_head);
}
#endif
/* longest_match() or longest_match_fast() sets match_start */
}
if (s->match_length >= MIN_MATCH) {
check_match(s, s->strstart, s->match_start, s->match_length);
@@ -1243,10 +1266,10 @@ local block_state deflate_fast(s, flush)
* always MIN_MATCH bytes ahead.
*/
} while (--s->match_length != 0);
s->strstart++;
s->strstart++;
} else
#endif
{
{
s->strstart += s->match_length;
s->match_length = 0;
s->ins_h = s->window[s->strstart];
@@ -1263,7 +1286,7 @@ local block_state deflate_fast(s, flush)
Tracevv((stderr,"%c", s->window[s->strstart]));
_tr_tally_lit (s, s->window[s->strstart], bflush);
s->lookahead--;
s->strstart++;
s->strstart++;
}
if (bflush) FLUSH_BLOCK(s, 0);
}
@@ -1271,6 +1294,7 @@ local block_state deflate_fast(s, flush)
return flush == Z_FINISH ? finish_done : block_done;
}
#ifndef FASTEST
/* ===========================================================================
* Same as above, but achieves better compression. We use a lazy
* evaluation for matches: a match is finally adopted only if there is
@@ -1293,8 +1317,8 @@ local block_state deflate_slow(s, flush)
if (s->lookahead < MIN_LOOKAHEAD) {
fill_window(s);
if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
return need_more;
}
return need_more;
}
if (s->lookahead == 0) break; /* flush the current block */
}
@@ -1316,10 +1340,12 @@ local block_state deflate_slow(s, flush)
* of window index 0 (in particular we have to avoid a match
* of the string with itself at the start of the input file).
*/
if (s->strategy != Z_HUFFMAN_ONLY) {
if (s->strategy < Z_HUFFMAN_ONLY) {
s->match_length = longest_match (s, hash_head);
} else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) {
s->match_length = longest_match_fast (s, hash_head);
}
/* longest_match() sets match_start */
/* longest_match() or longest_match_fast() sets match_start */
if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
(s->match_length == MIN_MATCH &&
@@ -1341,7 +1367,7 @@ local block_state deflate_slow(s, flush)
check_match(s, s->strstart-1, s->prev_match, s->prev_length);
_tr_tally_dist(s, s->strstart -1 - s->prev_match,
s->prev_length - MIN_MATCH, bflush);
s->prev_length - MIN_MATCH, bflush);
/* Insert in hash table all strings up to the end of the match.
* strstart-1 and strstart are already inserted. If there is not
@@ -1367,8 +1393,8 @@ local block_state deflate_slow(s, flush)
* is longer, truncate the previous match to a single literal.
*/
Tracevv((stderr,"%c", s->window[s->strstart-1]));
_tr_tally_lit(s, s->window[s->strstart-1], bflush);
if (bflush) {
_tr_tally_lit(s, s->window[s->strstart-1], bflush);
if (bflush) {
FLUSH_BLOCK_ONLY(s, 0);
}
s->strstart++;
@@ -1392,3 +1418,4 @@ local block_state deflate_slow(s, flush)
FLUSH_BLOCK(s, flush == Z_FINISH);
return flush == Z_FINISH ? finish_done : block_done;
}
#endif /* FASTEST */