/* deflate.c -- compress data using the deflation algorithm
- * Copyright (C) 1995-1998 Jean-loup Gailly.
- * For conditions of distribution and use, see copyright notice in zlib.h
+ * Copyright (C) 1995-2003 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
*/
/*
* REFERENCES
*
* Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
- * Available in ftp://ds.internic.net/rfc/rfc1951.txt
+ * Available in http://www.ietf.org/rfc/rfc1951.txt
*
* A description of the Rabin and Karp algorithm is given in the book
* "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
#include "deflate.h"
const char deflate_copyright[] =
- " deflate 1.1.2 Copyright 1995-1998 Jean-loup Gailly ";
+ " deflate 1.2.1 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
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,
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}}; /* max speed, no lazy matches */
+#else
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 */
+/* 1 */ {4, 4, 8, 4, deflate_fast}, /* max speed, no lazy matches */
/* 2 */ {4, 5, 16, 8, deflate_fast},
/* 3 */ {4, 6, 32, 32, deflate_fast},
/* 6 */ {8, 16, 128, 128, deflate_slow},
/* 7 */ {8, 32, 128, 256, deflate_slow},
/* 8 */ {32, 128, 258, 1024, deflate_slow},
-/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */
+/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* max 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
#define EQUAL 0
/* result of memcmp for equal strings */
+#ifndef NO_DUMMY_DECL
struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
+#endif
/* ===========================================================================
* Update a hash value with the given input byte
#else
#define INSERT_STRING(s, str, match_head) \
(UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
- s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
+ match_head = s->prev[(str) & s->w_mask] = s->head[s->ins_h], \
s->head[s->ins_h] = (Pos)(str))
#endif
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;
int stream_size;
{
deflate_state *s;
- int noheader = 0;
- static const char* my_version = ZLIB_VERSION;
+ int wrap = 1;
+ static const char my_version[] = ZLIB_VERSION;
ushf *overlay;
/* We overlay pending_buf and d_buf+l_buf. This works since the average
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;
+ if (strm->zalloc == (alloc_func)0) {
+ strm->zalloc = zcalloc;
+ strm->opaque = (voidpf)0;
}
- if (strm->zfree == Z_NULL) strm->zfree = zcfree;
+ if (strm->zfree == (free_func)0) 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 */
- noheader = 1;
+ if (windowBits < 0) { /* suppress zlib wrapper */
+ wrap = 0;
windowBits = -windowBits;
}
+#ifdef GZIP
+ else if (windowBits > 15) {
+ wrap = 2; /* write gzip wrapper instead */
+ windowBits -= 16;
+ }
+#endif
if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
windowBits < 8 || windowBits > 15 || level < 0 || level > 9 ||
- strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
+ strategy < 0 || strategy > Z_RLE) {
return Z_STREAM_ERROR;
}
+ if (windowBits == 8) windowBits = 9; /* until 256-byte window bug fixed */
s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
if (s == Z_NULL) return Z_MEM_ERROR;
strm->state = (struct internal_state FAR *)s;
s->strm = strm;
- s->noheader = noheader;
+ s->wrap = wrap;
s->w_bits = windowBits;
s->w_size = 1 << s->w_bits;
s->w_mask = s->w_size - 1;
if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
s->pending_buf == Z_NULL) {
+ s->status = FINISH_STATE;
strm->msg = (char*)ERR_MSG(Z_MEM_ERROR);
deflateEnd (strm);
return Z_MEM_ERROR;
IPos hash_head = 0;
if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL ||
- strm->state->status != INIT_STATE) return Z_STREAM_ERROR;
+ strm->state->wrap == 2 ||
+ (strm->state->wrap == 1 && strm->state->status != INIT_STATE))
+ return Z_STREAM_ERROR;
s = strm->state;
- strm->adler = adler32(strm->adler, dictionary, dictLength);
+ if (s->wrap)
+ strm->adler = adler32(strm->adler, 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);
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;
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;
+ strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0) {
+ return Z_STREAM_ERROR;
+ }
strm->total_in = strm->total_out = 0;
strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
s->pending = 0;
s->pending_out = s->pending_buf;
- if (s->noheader < 0) {
- s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
+ if (s->wrap < 0) {
+ s->wrap = -s->wrap; /* was made negative by deflate(..., Z_FINISH); */
}
- s->status = s->noheader ? BUSY_STATE : INIT_STATE;
- strm->adler = 1;
+ s->status = s->wrap ? INIT_STATE : BUSY_STATE;
+ strm->adler =
+#ifdef GZIP
+ s->wrap == 2 ? crc32(0L, Z_NULL, 0) :
+#endif
+ adler32(0L, Z_NULL, 0);
s->last_flush = Z_NO_FLUSH;
_tr_init(s);
return Z_OK;
}
+/* ========================================================================= */
+int ZEXPORT deflatePrime (strm, bits, value)
+ z_streamp strm;
+ int bits;
+ int value;
+{
+ if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+ strm->state->bi_valid = bits;
+ strm->state->bi_buf = (ush)(value & ((1 << bits) - 1));
+ return Z_OK;
+}
+
/* ========================================================================= */
int ZEXPORT deflateParams(strm, level, strategy)
z_streamp strm;
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;
}
+/* =========================================================================
+ * For the default windowBits of 15 and memLevel of 8, this function returns
+ * a close to exact, as well as small, upper bound on the compressed size.
+ * They are coded as constants here for a reason--if the #define's are
+ * changed, then this function needs to be changed as well. The return
+ * value for 15 and 8 only works for those exact settings.
+ *
+ * For any setting other than those defaults for windowBits and memLevel,
+ * the value returned is a conservative worst case for the maximum expansion
+ * resulting from using fixed blocks instead of stored blocks, which deflate
+ * can emit on compressed data for some combinations of the parameters.
+ *
+ * This function could be more sophisticated to provide closer upper bounds
+ * for every combination of windowBits and memLevel, as well as wrap.
+ * But even the conservative upper bound of about 14% expansion does not
+ * seem onerous for output buffer allocation.
+ */
+uLong ZEXPORT deflateBound(strm, sourceLen)
+ z_streamp strm;
+ uLong sourceLen;
+{
+ deflate_state *s;
+ uLong destLen;
+
+ /* conservative upper bound */
+ destLen = sourceLen +
+ ((sourceLen + 7) >> 3) + ((sourceLen + 63) >> 6) + 11;
+
+ /* if can't get parameters, return conservative bound */
+ if (strm == Z_NULL || strm->state == Z_NULL)
+ return destLen;
+
+ /* if not default parameters, return conservative bound */
+ s = strm->state;
+ if (s->w_bits != 15 || s->hash_bits != 8 + 7)
+ return destLen;
+
+ /* default settings: return tight bound for that case */
+ return compressBound(sourceLen);
+}
+
/* =========================================================================
* Put a short in the pending buffer. The 16-bit value is put in MSB order.
* IN assertion: the stream state is correct and there is enough room in
{
put_byte(s, (Byte)(b >> 8));
put_byte(s, (Byte)(b & 0xff));
-}
+}
/* =========================================================================
* Flush as much pending output as possible. All deflate() output goes
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);
old_flush = s->last_flush;
s->last_flush = flush;
- /* Write the zlib header */
+ /* Write the header */
if (s->status == INIT_STATE) {
-
- uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
- uInt level_flags = (s->level-1) >> 1;
-
- if (level_flags > 3) level_flags = 3;
- header |= (level_flags << 6);
- 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;
+#ifdef GZIP
+ if (s->wrap == 2) {
+ put_byte(s, 31);
+ put_byte(s, 139);
+ put_byte(s, 8);
+ put_byte(s, 0);
+ put_byte(s, 0);
+ put_byte(s, 0);
+ put_byte(s, 0);
+ put_byte(s, 0);
+ put_byte(s, s->level == 9 ? 2 :
+ (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ?
+ 4 : 0));
+ put_byte(s, 255);
+ s->status = BUSY_STATE;
+ strm->adler = crc32(0L, Z_NULL, 0);
+ }
+ else
+#endif
+ {
+ uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
+ uInt level_flags;
+
+ if (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2)
+ level_flags = 0;
+ else if (s->level < 6)
+ level_flags = 1;
+ else if (s->level == 6)
+ level_flags = 2;
+ else
+ level_flags = 3;
+ header |= (level_flags << 6);
+ 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 = adler32(0L, Z_NULL, 0);
+ }
}
/* 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);
}
(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);
}
}
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");
if (flush != Z_FINISH) return Z_OK;
- if (s->noheader) return Z_STREAM_END;
-
- /* Write the zlib trailer (adler32) */
- putShortMSB(s, (uInt)(strm->adler >> 16));
- putShortMSB(s, (uInt)(strm->adler & 0xffff));
+ if (s->wrap <= 0) return Z_STREAM_END;
+
+ /* Write the trailer */
+#ifdef GZIP
+ if (s->wrap == 2) {
+ put_byte(s, (Byte)(strm->adler & 0xff));
+ put_byte(s, (Byte)((strm->adler >> 8) & 0xff));
+ put_byte(s, (Byte)((strm->adler >> 16) & 0xff));
+ put_byte(s, (Byte)((strm->adler >> 24) & 0xff));
+ put_byte(s, (Byte)(strm->total_in & 0xff));
+ put_byte(s, (Byte)((strm->total_in >> 8) & 0xff));
+ put_byte(s, (Byte)((strm->total_in >> 16) & 0xff));
+ put_byte(s, (Byte)((strm->total_in >> 24) & 0xff));
+ }
+ else
+#endif
+ {
+ putShortMSB(s, (uInt)(strm->adler >> 16));
+ putShortMSB(s, (uInt)(strm->adler & 0xffff));
+ }
flush_pending(strm);
/* If avail_out is zero, the application will call deflate again
* to flush the rest.
*/
- s->noheader = -1; /* write the trailer only once! */
+ if (s->wrap > 0) s->wrap = -s->wrap; /* write the trailer only once! */
return s->pending != 0 ? Z_OK : Z_STREAM_END;
}
status = strm->state->status;
if (status != INIT_STATE && status != BUSY_STATE &&
- status != FINISH_STATE) {
+ status != FINISH_STATE) {
return Z_STREAM_ERROR;
}
deflate_state *ss;
ushf *overlay;
- ss = source->state;
- if (source == Z_NULL || dest == Z_NULL || ss == Z_NULL) {
+ if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {
return Z_STREAM_ERROR;
}
+
+ ss = source->state;
+
*dest = *source;
ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
ds->bl_desc.dyn_tree = ds->bl_tree;
return Z_OK;
-#endif
+#endif /* MAXSEG_64K */
}
/* ===========================================================================
strm->avail_in -= len;
- if (!strm->state->noheader) {
+ if (strm->state->wrap == 1) {
strm->adler = adler32(strm->adler, strm->next_in, len);
}
+#ifdef GZIP
+ else if (strm->state->wrap == 2) {
+ strm->adler = crc32(strm->adler, strm->next_in, len);
+ }
+#endif
zmemcpy(buf, strm->next_in, len);
strm->next_in += len;
strm->total_in += len;
#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,
/* 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 */
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 */
{
*/
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");
if (len < MIN_MATCH) return MIN_MATCH - 1;
s->match_start = cur_match;
- return len <= s->lookahead ? len : s->lookahead;
+ return (uInt)len <= s->lookahead ? (uInt)len : s->lookahead;
}
-#endif /* FASTEST */
-#endif /* ASMV */
#ifdef DEBUG
/* ===========================================================================
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) {
}
#else
# define check_match(s, start, match, length)
-#endif
+#endif /* DEBUG */
/* ===========================================================================
* Fill the window when the lookahead becomes insufficient.
more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
/* Deal with !@#$% 64K limit: */
- if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
- more = wsize;
+ if (sizeof(int) <= 2) {
+ if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
+ more = wsize;
- } else if (more == (unsigned)(-1)) {
- /* Very unlikely, but possible on 16 bit machine if strstart == 0
- * and lookahead == 1 (input done one byte at time)
- */
- more--;
+ } else if (more == (unsigned)(-1)) {
+ /* Very unlikely, but possible on 16 bit machine if
+ * strstart == 0 && lookahead == 1 (input done a byte at time)
+ */
+ more--;
+ }
+ }
/* If the window is almost full and there is insufficient lookahead,
* move the upper half to the lower one to make room in the upper half.
*/
- } else if (s->strstart >= wsize+MAX_DIST(s)) {
+ if (s->strstart >= wsize+MAX_DIST(s)) {
zmemcpy(s->window, s->window+wsize, (unsigned)wsize);
s->match_start -= wsize;
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;
+ n = s->hash_size;
+ p = &s->head[n];
+ do {
+ m = *--p;
+ *p = (Pos)(m >= wsize ? m-wsize : NIL);
+ } while (--n);
+
+ 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;
}
_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]")); \
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;
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 */
}
* 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) {
+#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);
+ }
+#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);
}
- /* longest_match() sets match_start */
+#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);
#ifndef FASTEST
if (s->match_length <= s->max_insert_length &&
s->lookahead >= MIN_MATCH) {
- s->match_length--; /* string at strstart already in hash table */
+ s->match_length--; /* string at strstart already in table */
do {
s->strstart++;
INSERT_STRING(s, s->strstart, hash_head);
* 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];
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);
}
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
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 */
}
* 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 &&
- s->strstart - s->match_start > TOO_FAR))) {
+ if (s->match_length <= 5 && (s->strategy == Z_FILTERED
+#if TOO_FAR <= 32767
+ || (s->match_length == MIN_MATCH &&
+ s->strstart - s->match_start > TOO_FAR)
+#endif
+ )) {
/* If prev_match is also MIN_MATCH, match_start is garbage
* but we will ignore the current match anyway.
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
* 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++;
FLUSH_BLOCK(s, flush == Z_FINISH);
return flush == Z_FINISH ? finish_done : block_done;
}
+#endif /* FASTEST */
projects / wxWidgets.git / blobdiff