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authorNick Clifton <nickc@redhat.com>2017-01-20 10:17:42 +0000
committerNick Clifton <nickc@redhat.com>2017-01-20 10:17:42 +0000
commitde1ab01e8ebf04a3503d8450e6b924c7bb160853 (patch)
treee5c91c036f0d1fcd2f1853908e98cffa1d8fa1f7 /zlib/deflate.c
parent1737c64030af533c520dd1ed1ec2787302cdf830 (diff)
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Sync zlib sources with GCC, upgrading to 1.2.10.
Changes in 1.2.10 (2 Jan 2017) - Avoid warnings on snprintf() return value - Fix bug in deflate_stored() for zero-length input - Fix bug in gzwrite.c that produced corrupt gzip files - Remove files to be installed before copying them in Makefile.in - Add warnings when compiling with assembler code Changes in 1.2.9 (31 Dec 2016) - Fix contrib/minizip to permit unzipping with desktop API [Zouzou] - Improve contrib/blast to return unused bytes - Assure that gzoffset() is correct when appending - Improve compress() and uncompress() to support large lengths - Fix bug in test/example.c where error code not saved - Remedy Coverity warning [Randers-Pehrson] - Improve speed of gzprintf() in transparent mode - Fix inflateInit2() bug when windowBits is 16 or 32 - Change DEBUG macro to ZLIB_DEBUG - Avoid uninitialized access by gzclose_w() - Allow building zlib outside of the source directory - Fix bug that accepted invalid zlib header when windowBits is zero - Fix gzseek() problem on MinGW due to buggy _lseeki64 there - Loop on write() calls in gzwrite.c in case of non-blocking I/O - Add --warn (-w) option to ./configure for more compiler warnings - Reject a window size of 256 bytes if not using the zlib wrapper - Fix bug when level 0 used with Z_HUFFMAN or Z_RLE - Add --debug (-d) option to ./configure to define ZLIB_DEBUG - Fix bugs in creating a very large gzip header - Add uncompress2() function, which returns the input size used - Assure that deflateParams() will not switch functions mid-block - Dramatically speed up deflation for level 0 (storing) - Add gzfread(), duplicating the interface of fread() - Add gzfwrite(), duplicating the interface of fwrite() - Add deflateGetDictionary() function - Use snprintf() for later versions of Microsoft C - Fix *Init macros to use z_ prefix when requested - Replace as400 with os400 for OS/400 support [Monnerat] - Add crc32_z() and adler32_z() functions with size_t lengths - Update Visual Studio project files [AraHaan]
Diffstat (limited to 'zlib/deflate.c')
-rw-r--r--zlib/deflate.c799
1 files changed, 495 insertions, 304 deletions
diff --git a/zlib/deflate.c b/zlib/deflate.c
index 03e76ab..faff1b7 100644
--- a/zlib/deflate.c
+++ b/zlib/deflate.c
@@ -1,5 +1,5 @@
/* deflate.c -- compress data using the deflation algorithm
- * Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler
+ * Copyright (C) 1995-2017 Jean-loup Gailly and Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@@ -52,7 +52,7 @@
#include "deflate.h"
const char deflate_copyright[] =
- " deflate 1.2.8 Copyright 1995-2013 Jean-loup Gailly and Mark Adler ";
+ " deflate 1.2.10 Copyright 1995-2017 Jean-loup Gailly and Mark Adler ";
/*
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
@@ -73,6 +73,8 @@ typedef enum {
typedef block_state (*compress_func) OF((deflate_state *s, int flush));
/* Compression function. Returns the block state after the call. */
+local int deflateStateCheck OF((z_streamp strm));
+local void slide_hash OF((deflate_state *s));
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));
@@ -84,15 +86,16 @@ local block_state deflate_huff OF((deflate_state *s, int flush));
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));
+local unsigned read_buf OF((z_streamp strm, Bytef *buf, unsigned size));
#ifdef ASMV
+# pragma message("Assembler code may have bugs -- use at your own risk")
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
+#ifdef ZLIB_DEBUG
local void check_match OF((deflate_state *s, IPos start, IPos match,
int length));
#endif
@@ -148,21 +151,14 @@ local const config configuration_table[10] = {
* meaning.
*/
-#define EQUAL 0
-/* result of memcmp for equal strings */
-
-#ifndef NO_DUMMY_DECL
-struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
-#endif
-
/* rank Z_BLOCK between Z_NO_FLUSH and Z_PARTIAL_FLUSH */
-#define RANK(f) (((f) << 1) - ((f) > 4 ? 9 : 0))
+#define RANK(f) (((f) * 2) - ((f) > 4 ? 9 : 0))
/* ===========================================================================
* Update a hash value with the given input byte
- * IN assertion: all calls to to UPDATE_HASH are made with consecutive
- * input characters, so that a running hash key can be computed from the
- * previous key instead of complete recalculation each time.
+ * IN assertion: all calls to UPDATE_HASH are made with consecutive input
+ * characters, so that a running hash key can be computed from the previous
+ * key instead of complete recalculation each time.
*/
#define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
@@ -173,9 +169,9 @@ struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
* the previous length of the hash chain.
* If this file is compiled with -DFASTEST, the compression level is forced
* to 1, and no hash chains are maintained.
- * IN assertion: all calls to to INSERT_STRING are made with consecutive
- * input characters and the first MIN_MATCH bytes of str are valid
- * (except for the last MIN_MATCH-1 bytes of the input file).
+ * IN assertion: all calls to INSERT_STRING are made with consecutive input
+ * characters and the first MIN_MATCH bytes of str are valid (except for
+ * the last MIN_MATCH-1 bytes of the input file).
*/
#ifdef FASTEST
#define INSERT_STRING(s, str, match_head) \
@@ -197,6 +193,37 @@ struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
s->head[s->hash_size-1] = NIL; \
zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
+/* ===========================================================================
+ * Slide the hash table when sliding the window down (could be avoided with 32
+ * bit values 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.
+ */
+local void slide_hash(s)
+ deflate_state *s;
+{
+ unsigned n, m;
+ Posf *p;
+ uInt wsize = s->w_size;
+
+ 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);
+#endif
+}
+
/* ========================================================================= */
int ZEXPORT deflateInit_(strm, level, version, stream_size)
z_streamp strm;
@@ -270,7 +297,7 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
#endif
if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
windowBits < 8 || windowBits > 15 || level < 0 || level > 9 ||
- strategy < 0 || strategy > Z_FIXED) {
+ strategy < 0 || strategy > Z_FIXED || (windowBits == 8 && wrap != 1)) {
return Z_STREAM_ERROR;
}
if (windowBits == 8) windowBits = 9; /* until 256-byte window bug fixed */
@@ -278,14 +305,15 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
if (s == Z_NULL) return Z_MEM_ERROR;
strm->state = (struct internal_state FAR *)s;
s->strm = strm;
+ s->status = INIT_STATE; /* to pass state test in deflateReset() */
s->wrap = wrap;
s->gzhead = Z_NULL;
- s->w_bits = windowBits;
+ s->w_bits = (uInt)windowBits;
s->w_size = 1 << s->w_bits;
s->w_mask = s->w_size - 1;
- s->hash_bits = memLevel + 7;
+ s->hash_bits = (uInt)memLevel + 7;
s->hash_size = 1 << s->hash_bits;
s->hash_mask = s->hash_size - 1;
s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
@@ -319,6 +347,31 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
return deflateReset(strm);
}
+/* =========================================================================
+ * Check for a valid deflate stream state. Return 0 if ok, 1 if not.
+ */
+local int deflateStateCheck (strm)
+ z_streamp strm;
+{
+ deflate_state *s;
+ if (strm == Z_NULL ||
+ strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0)
+ return 1;
+ s = strm->state;
+ if (s == Z_NULL || s->strm != strm || (s->status != INIT_STATE &&
+#ifdef GZIP
+ s->status != GZIP_STATE &&
+#endif
+ s->status != EXTRA_STATE &&
+ s->status != NAME_STATE &&
+ s->status != COMMENT_STATE &&
+ s->status != HCRC_STATE &&
+ s->status != BUSY_STATE &&
+ s->status != FINISH_STATE))
+ return 1;
+ return 0;
+}
+
/* ========================================================================= */
int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
z_streamp strm;
@@ -331,7 +384,7 @@ int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
unsigned avail;
z_const unsigned char *next;
- if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL)
+ if (deflateStateCheck(strm) || dictionary == Z_NULL)
return Z_STREAM_ERROR;
s = strm->state;
wrap = s->wrap;
@@ -389,13 +442,34 @@ int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
}
/* ========================================================================= */
+int ZEXPORT deflateGetDictionary (strm, dictionary, dictLength)
+ z_streamp strm;
+ Bytef *dictionary;
+ uInt *dictLength;
+{
+ deflate_state *s;
+ uInt len;
+
+ if (deflateStateCheck(strm))
+ return Z_STREAM_ERROR;
+ s = strm->state;
+ len = s->strstart + s->lookahead;
+ if (len > s->w_size)
+ len = s->w_size;
+ if (dictionary != Z_NULL && len)
+ zmemcpy(dictionary, s->window + s->strstart + s->lookahead - len, len);
+ if (dictLength != Z_NULL)
+ *dictLength = len;
+ return Z_OK;
+}
+
+/* ========================================================================= */
int ZEXPORT deflateResetKeep (strm)
z_streamp strm;
{
deflate_state *s;
- if (strm == Z_NULL || strm->state == Z_NULL ||
- strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0) {
+ if (deflateStateCheck(strm)) {
return Z_STREAM_ERROR;
}
@@ -410,7 +484,11 @@ int ZEXPORT deflateResetKeep (strm)
if (s->wrap < 0) {
s->wrap = -s->wrap; /* was made negative by deflate(..., Z_FINISH); */
}
- s->status = s->wrap ? INIT_STATE : BUSY_STATE;
+ s->status =
+#ifdef GZIP
+ s->wrap == 2 ? GZIP_STATE :
+#endif
+ s->wrap ? INIT_STATE : BUSY_STATE;
strm->adler =
#ifdef GZIP
s->wrap == 2 ? crc32(0L, Z_NULL, 0) :
@@ -440,8 +518,8 @@ int ZEXPORT deflateSetHeader (strm, head)
z_streamp strm;
gz_headerp head;
{
- if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
- if (strm->state->wrap != 2) return Z_STREAM_ERROR;
+ if (deflateStateCheck(strm) || strm->state->wrap != 2)
+ return Z_STREAM_ERROR;
strm->state->gzhead = head;
return Z_OK;
}
@@ -452,7 +530,7 @@ int ZEXPORT deflatePending (strm, pending, bits)
int *bits;
z_streamp strm;
{
- if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+ if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
if (pending != Z_NULL)
*pending = strm->state->pending;
if (bits != Z_NULL)
@@ -469,7 +547,7 @@ int ZEXPORT deflatePrime (strm, bits, value)
deflate_state *s;
int put;
- if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+ if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
s = strm->state;
if ((Bytef *)(s->d_buf) < s->pending_out + ((Buf_size + 7) >> 3))
return Z_BUF_ERROR;
@@ -494,9 +572,8 @@ int ZEXPORT deflateParams(strm, level, strategy)
{
deflate_state *s;
compress_func func;
- int err = Z_OK;
- if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+ if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
s = strm->state;
#ifdef FASTEST
@@ -509,14 +586,22 @@ int ZEXPORT deflateParams(strm, level, strategy)
}
func = configuration_table[s->level].func;
- if ((strategy != s->strategy || func != configuration_table[level].func) &&
- strm->total_in != 0) {
+ if ((strategy != s->strategy || func != configuration_table[level].func)) {
/* Flush the last buffer: */
- err = deflate(strm, Z_BLOCK);
- if (err == Z_BUF_ERROR && s->pending == 0)
- err = Z_OK;
+ int err = deflate(strm, Z_BLOCK);
+ if (err == Z_STREAM_ERROR)
+ return err;
+ if (strm->avail_out == 0)
+ return Z_BUF_ERROR;
}
if (s->level != level) {
+ if (s->level == 0 && s->matches != 0) {
+ if (s->matches == 1)
+ slide_hash(s);
+ else
+ CLEAR_HASH(s);
+ s->matches = 0;
+ }
s->level = level;
s->max_lazy_match = configuration_table[level].max_lazy;
s->good_match = configuration_table[level].good_length;
@@ -524,7 +609,7 @@ int ZEXPORT deflateParams(strm, level, strategy)
s->max_chain_length = configuration_table[level].max_chain;
}
s->strategy = strategy;
- return err;
+ return Z_OK;
}
/* ========================================================================= */
@@ -537,12 +622,12 @@ int ZEXPORT deflateTune(strm, good_length, max_lazy, nice_length, max_chain)
{
deflate_state *s;
- if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+ if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
s = strm->state;
- s->good_match = good_length;
- s->max_lazy_match = max_lazy;
+ s->good_match = (uInt)good_length;
+ s->max_lazy_match = (uInt)max_lazy;
s->nice_match = nice_length;
- s->max_chain_length = max_chain;
+ s->max_chain_length = (uInt)max_chain;
return Z_OK;
}
@@ -569,14 +654,13 @@ uLong ZEXPORT deflateBound(strm, sourceLen)
{
deflate_state *s;
uLong complen, wraplen;
- Bytef *str;
/* conservative upper bound for compressed data */
complen = sourceLen +
((sourceLen + 7) >> 3) + ((sourceLen + 63) >> 6) + 5;
/* if can't get parameters, return conservative bound plus zlib wrapper */
- if (strm == Z_NULL || strm->state == Z_NULL)
+ if (deflateStateCheck(strm))
return complen + 6;
/* compute wrapper length */
@@ -588,9 +672,11 @@ uLong ZEXPORT deflateBound(strm, sourceLen)
case 1: /* zlib wrapper */
wraplen = 6 + (s->strstart ? 4 : 0);
break;
+#ifdef GZIP
case 2: /* gzip wrapper */
wraplen = 18;
if (s->gzhead != Z_NULL) { /* user-supplied gzip header */
+ Bytef *str;
if (s->gzhead->extra != Z_NULL)
wraplen += 2 + s->gzhead->extra_len;
str = s->gzhead->name;
@@ -607,6 +693,7 @@ uLong ZEXPORT deflateBound(strm, sourceLen)
wraplen += 2;
}
break;
+#endif
default: /* for compiler happiness */
wraplen = 6;
}
@@ -634,10 +721,10 @@ local void putShortMSB (s, b)
}
/* =========================================================================
- * Flush as much pending output as possible. All deflate() output goes
- * through this function so some applications may wish to modify it
- * to avoid allocating a large strm->next_out buffer and copying into it.
- * (See also read_buf()).
+ * Flush as much pending output as possible. All deflate() output, except for
+ * some deflate_stored() output, goes through this function so some
+ * applications may wish to modify it to avoid allocating a large
+ * strm->next_out buffer and copying into it. (See also read_buf()).
*/
local void flush_pending(strm)
z_streamp strm;
@@ -654,13 +741,23 @@ local void flush_pending(strm)
strm->next_out += len;
s->pending_out += len;
strm->total_out += len;
- strm->avail_out -= len;
- s->pending -= len;
+ strm->avail_out -= len;
+ s->pending -= len;
if (s->pending == 0) {
s->pending_out = s->pending_buf;
}
}
+/* ===========================================================================
+ * Update the header CRC with the bytes s->pending_buf[beg..s->pending - 1].
+ */
+#define HCRC_UPDATE(beg) \
+ do { \
+ if (s->gzhead->hcrc && s->pending > (beg)) \
+ strm->adler = crc32(strm->adler, s->pending_buf + (beg), \
+ s->pending - (beg)); \
+ } while (0)
+
/* ========================================================================= */
int ZEXPORT deflate (strm, flush)
z_streamp strm;
@@ -669,230 +766,229 @@ int ZEXPORT deflate (strm, flush)
int old_flush; /* value of flush param for previous deflate call */
deflate_state *s;
- if (strm == Z_NULL || strm->state == Z_NULL ||
- flush > Z_BLOCK || flush < 0) {
+ if (deflateStateCheck(strm) || flush > Z_BLOCK || flush < 0) {
return Z_STREAM_ERROR;
}
s = strm->state;
if (strm->next_out == Z_NULL ||
- (strm->next_in == Z_NULL && strm->avail_in != 0) ||
+ (strm->avail_in != 0 && strm->next_in == Z_NULL) ||
(s->status == FINISH_STATE && flush != Z_FINISH)) {
ERR_RETURN(strm, Z_STREAM_ERROR);
}
if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
- s->strm = strm; /* just in case */
old_flush = s->last_flush;
s->last_flush = flush;
+ /* 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:
+ */
+ 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_BUF_ERROR.
+ */
+ } else if (strm->avail_in == 0 && RANK(flush) <= RANK(old_flush) &&
+ flush != Z_FINISH) {
+ ERR_RETURN(strm, Z_BUF_ERROR);
+ }
+
+ /* User must not provide more input after the first FINISH: */
+ if (s->status == FINISH_STATE && strm->avail_in != 0) {
+ ERR_RETURN(strm, Z_BUF_ERROR);
+ }
+
/* Write the header */
if (s->status == INIT_STATE) {
-#ifdef GZIP
- if (s->wrap == 2) {
- strm->adler = crc32(0L, Z_NULL, 0);
- put_byte(s, 31);
- put_byte(s, 139);
- put_byte(s, 8);
- if (s->gzhead == Z_NULL) {
- 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, OS_CODE);
- s->status = BUSY_STATE;
- }
- else {
- put_byte(s, (s->gzhead->text ? 1 : 0) +
- (s->gzhead->hcrc ? 2 : 0) +
- (s->gzhead->extra == Z_NULL ? 0 : 4) +
- (s->gzhead->name == Z_NULL ? 0 : 8) +
- (s->gzhead->comment == Z_NULL ? 0 : 16)
- );
- put_byte(s, (Byte)(s->gzhead->time & 0xff));
- put_byte(s, (Byte)((s->gzhead->time >> 8) & 0xff));
- put_byte(s, (Byte)((s->gzhead->time >> 16) & 0xff));
- put_byte(s, (Byte)((s->gzhead->time >> 24) & 0xff));
- put_byte(s, s->level == 9 ? 2 :
- (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ?
- 4 : 0));
- put_byte(s, s->gzhead->os & 0xff);
- if (s->gzhead->extra != Z_NULL) {
- put_byte(s, s->gzhead->extra_len & 0xff);
- put_byte(s, (s->gzhead->extra_len >> 8) & 0xff);
- }
- if (s->gzhead->hcrc)
- strm->adler = crc32(strm->adler, s->pending_buf,
- s->pending);
- s->gzindex = 0;
- s->status = EXTRA_STATE;
- }
- }
+ /* zlib header */
+ 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
-#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);
+ level_flags = 3;
+ header |= (level_flags << 6);
+ if (s->strstart != 0) header |= PRESET_DICT;
+ header += 31 - (header % 31);
+
+ 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);
+ s->status = BUSY_STATE;
+
+ /* Compression must start with an empty pending buffer */
+ flush_pending(strm);
+ if (s->pending != 0) {
+ s->last_flush = -1;
+ return Z_OK;
+ }
+ }
+#ifdef GZIP
+ if (s->status == GZIP_STATE) {
+ /* gzip header */
+ strm->adler = crc32(0L, Z_NULL, 0);
+ put_byte(s, 31);
+ put_byte(s, 139);
+ put_byte(s, 8);
+ if (s->gzhead == Z_NULL) {
+ 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, OS_CODE);
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));
+ /* Compression must start with an empty pending buffer */
+ flush_pending(strm);
+ if (s->pending != 0) {
+ s->last_flush = -1;
+ return Z_OK;
+ }
+ }
+ else {
+ put_byte(s, (s->gzhead->text ? 1 : 0) +
+ (s->gzhead->hcrc ? 2 : 0) +
+ (s->gzhead->extra == Z_NULL ? 0 : 4) +
+ (s->gzhead->name == Z_NULL ? 0 : 8) +
+ (s->gzhead->comment == Z_NULL ? 0 : 16)
+ );
+ put_byte(s, (Byte)(s->gzhead->time & 0xff));
+ put_byte(s, (Byte)((s->gzhead->time >> 8) & 0xff));
+ put_byte(s, (Byte)((s->gzhead->time >> 16) & 0xff));
+ put_byte(s, (Byte)((s->gzhead->time >> 24) & 0xff));
+ put_byte(s, s->level == 9 ? 2 :
+ (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ?
+ 4 : 0));
+ put_byte(s, s->gzhead->os & 0xff);
+ if (s->gzhead->extra != Z_NULL) {
+ put_byte(s, s->gzhead->extra_len & 0xff);
+ put_byte(s, (s->gzhead->extra_len >> 8) & 0xff);
}
- strm->adler = adler32(0L, Z_NULL, 0);
+ if (s->gzhead->hcrc)
+ strm->adler = crc32(strm->adler, s->pending_buf,
+ s->pending);
+ s->gzindex = 0;
+ s->status = EXTRA_STATE;
}
}
-#ifdef GZIP
if (s->status == EXTRA_STATE) {
if (s->gzhead->extra != Z_NULL) {
- uInt beg = s->pending; /* start of bytes to update crc */
-
- while (s->gzindex < (s->gzhead->extra_len & 0xffff)) {
- if (s->pending == s->pending_buf_size) {
- if (s->gzhead->hcrc && s->pending > beg)
- strm->adler = crc32(strm->adler, s->pending_buf + beg,
- s->pending - beg);
- flush_pending(strm);
- beg = s->pending;
- if (s->pending == s->pending_buf_size)
- break;
+ ulg beg = s->pending; /* start of bytes to update crc */
+ uInt left = (s->gzhead->extra_len & 0xffff) - s->gzindex;
+ while (s->pending + left > s->pending_buf_size) {
+ uInt copy = s->pending_buf_size - s->pending;
+ zmemcpy(s->pending_buf + s->pending,
+ s->gzhead->extra + s->gzindex, copy);
+ s->pending = s->pending_buf_size;
+ HCRC_UPDATE(beg);
+ s->gzindex += copy;
+ flush_pending(strm);
+ if (s->pending != 0) {
+ s->last_flush = -1;
+ return Z_OK;
}
- put_byte(s, s->gzhead->extra[s->gzindex]);
- s->gzindex++;
- }
- if (s->gzhead->hcrc && s->pending > beg)
- strm->adler = crc32(strm->adler, s->pending_buf + beg,
- s->pending - beg);
- if (s->gzindex == s->gzhead->extra_len) {
- s->gzindex = 0;
- s->status = NAME_STATE;
+ beg = 0;
+ left -= copy;
}
+ zmemcpy(s->pending_buf + s->pending,
+ s->gzhead->extra + s->gzindex, left);
+ s->pending += left;
+ HCRC_UPDATE(beg);
+ s->gzindex = 0;
}
- else
- s->status = NAME_STATE;
+ s->status = NAME_STATE;
}
if (s->status == NAME_STATE) {
if (s->gzhead->name != Z_NULL) {
- uInt beg = s->pending; /* start of bytes to update crc */
+ ulg beg = s->pending; /* start of bytes to update crc */
int val;
-
do {
if (s->pending == s->pending_buf_size) {
- if (s->gzhead->hcrc && s->pending > beg)
- strm->adler = crc32(strm->adler, s->pending_buf + beg,
- s->pending - beg);
+ HCRC_UPDATE(beg);
flush_pending(strm);
- beg = s->pending;
- if (s->pending == s->pending_buf_size) {
- val = 1;
- break;
+ if (s->pending != 0) {
+ s->last_flush = -1;
+ return Z_OK;
}
+ beg = 0;
}
val = s->gzhead->name[s->gzindex++];
put_byte(s, val);
} while (val != 0);
- if (s->gzhead->hcrc && s->pending > beg)
- strm->adler = crc32(strm->adler, s->pending_buf + beg,
- s->pending - beg);
- if (val == 0) {
- s->gzindex = 0;
- s->status = COMMENT_STATE;
- }
+ HCRC_UPDATE(beg);
+ s->gzindex = 0;
}
- else
- s->status = COMMENT_STATE;
+ s->status = COMMENT_STATE;
}
if (s->status == COMMENT_STATE) {
if (s->gzhead->comment != Z_NULL) {
- uInt beg = s->pending; /* start of bytes to update crc */
+ ulg beg = s->pending; /* start of bytes to update crc */
int val;
-
do {
if (s->pending == s->pending_buf_size) {
- if (s->gzhead->hcrc && s->pending > beg)
- strm->adler = crc32(strm->adler, s->pending_buf + beg,
- s->pending - beg);
+ HCRC_UPDATE(beg);
flush_pending(strm);
- beg = s->pending;
- if (s->pending == s->pending_buf_size) {
- val = 1;
- break;
+ if (s->pending != 0) {
+ s->last_flush = -1;
+ return Z_OK;
}
+ beg = 0;
}
val = s->gzhead->comment[s->gzindex++];
put_byte(s, val);
} while (val != 0);
- if (s->gzhead->hcrc && s->pending > beg)
- strm->adler = crc32(strm->adler, s->pending_buf + beg,
- s->pending - beg);
- if (val == 0)
- s->status = HCRC_STATE;
+ HCRC_UPDATE(beg);
}
- else
- s->status = HCRC_STATE;
+ s->status = HCRC_STATE;
}
if (s->status == HCRC_STATE) {
if (s->gzhead->hcrc) {
- if (s->pending + 2 > s->pending_buf_size)
+ if (s->pending + 2 > s->pending_buf_size) {
flush_pending(strm);
- if (s->pending + 2 <= s->pending_buf_size) {
- put_byte(s, (Byte)(strm->adler & 0xff));
- put_byte(s, (Byte)((strm->adler >> 8) & 0xff));
- strm->adler = crc32(0L, Z_NULL, 0);
- s->status = BUSY_STATE;
+ if (s->pending != 0) {
+ s->last_flush = -1;
+ return Z_OK;
+ }
}
+ put_byte(s, (Byte)(strm->adler & 0xff));
+ put_byte(s, (Byte)((strm->adler >> 8) & 0xff));
+ strm->adler = crc32(0L, Z_NULL, 0);
}
- else
- s->status = BUSY_STATE;
- }
-#endif
+ s->status = BUSY_STATE;
- /* Flush as much pending output as possible */
- if (s->pending != 0) {
+ /* Compression must start with an empty pending buffer */
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:
- */
+ if (s->pending != 0) {
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_BUF_ERROR.
- */
- } else if (strm->avail_in == 0 && RANK(flush) <= RANK(old_flush) &&
- flush != Z_FINISH) {
- ERR_RETURN(strm, Z_BUF_ERROR);
- }
-
- /* User must not provide more input after the first FINISH: */
- if (s->status == FINISH_STATE && strm->avail_in != 0) {
- ERR_RETURN(strm, Z_BUF_ERROR);
}
+#endif
/* Start a new block or continue the current one.
*/
@@ -900,9 +996,10 @@ int ZEXPORT deflate (strm, flush)
(flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
block_state bstate;
- bstate = s->strategy == Z_HUFFMAN_ONLY ? deflate_huff(s, flush) :
- (s->strategy == Z_RLE ? deflate_rle(s, flush) :
- (*(configuration_table[s->level].func))(s, flush));
+ bstate = s->level == 0 ? deflate_stored(s, flush) :
+ s->strategy == Z_HUFFMAN_ONLY ? deflate_huff(s, flush) :
+ s->strategy == Z_RLE ? deflate_rle(s, flush) :
+ (*(configuration_table[s->level].func))(s, flush);
if (bstate == finish_started || bstate == finish_done) {
s->status = FINISH_STATE;
@@ -944,7 +1041,6 @@ int ZEXPORT deflate (strm, flush)
}
}
}
- Assert(strm->avail_out > 0, "bug2");
if (flush != Z_FINISH) return Z_OK;
if (s->wrap <= 0) return Z_STREAM_END;
@@ -981,18 +1077,9 @@ int ZEXPORT deflateEnd (strm)
{
int status;
- if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+ if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
status = strm->state->status;
- if (status != INIT_STATE &&
- status != EXTRA_STATE &&
- status != NAME_STATE &&
- status != COMMENT_STATE &&
- status != HCRC_STATE &&
- status != BUSY_STATE &&
- status != FINISH_STATE) {
- return Z_STREAM_ERROR;
- }
/* Deallocate in reverse order of allocations: */
TRY_FREE(strm, strm->state->pending_buf);
@@ -1023,7 +1110,7 @@ int ZEXPORT deflateCopy (dest, source)
ushf *overlay;
- if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {
+ if (deflateStateCheck(source) || dest == Z_NULL) {
return Z_STREAM_ERROR;
}
@@ -1073,7 +1160,7 @@ int ZEXPORT deflateCopy (dest, source)
* allocating a large strm->next_in buffer and copying from it.
* (See also flush_pending()).
*/
-local int read_buf(strm, buf, size)
+local unsigned read_buf(strm, buf, size)
z_streamp strm;
Bytef *buf;
unsigned size;
@@ -1097,7 +1184,7 @@ local int read_buf(strm, buf, size)
strm->next_in += len;
strm->total_in += len;
- return (int)len;
+ return len;
}
/* ===========================================================================
@@ -1151,9 +1238,9 @@ local uInt longest_match(s, cur_match)
{
unsigned chain_length = s->max_chain_length;/* max hash chain length */
register Bytef *scan = s->window + s->strstart; /* current string */
- register Bytef *match; /* matched string */
+ register Bytef *match; /* matched string */
register int len; /* length of current match */
- int best_len = s->prev_length; /* best match length so far */
+ int best_len = (int)s->prev_length; /* best match length so far */
int nice_match = s->nice_match; /* stop if match long enough */
IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
s->strstart - (IPos)MAX_DIST(s) : NIL;
@@ -1188,7 +1275,7 @@ local uInt longest_match(s, cur_match)
/* Do not look for matches beyond the end of the input. This is necessary
* to make deflate deterministic.
*/
- if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
+ if ((uInt)nice_match > s->lookahead) nice_match = (int)s->lookahead;
Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
@@ -1349,7 +1436,11 @@ local uInt longest_match(s, cur_match)
#endif /* FASTEST */
-#ifdef DEBUG
+#ifdef ZLIB_DEBUG
+
+#define EQUAL 0
+/* result of memcmp for equal strings */
+
/* ===========================================================================
* Check that the match at match_start is indeed a match.
*/
@@ -1375,7 +1466,7 @@ local void check_match(s, start, match, length)
}
#else
# define check_match(s, start, match, length)
-#endif /* DEBUG */
+#endif /* ZLIB_DEBUG */
/* ===========================================================================
* Fill the window when the lookahead becomes insufficient.
@@ -1390,8 +1481,7 @@ local void check_match(s, start, match, length)
local void fill_window(s)
deflate_state *s;
{
- register unsigned n, m;
- register Posf *p;
+ unsigned n;
unsigned more; /* Amount of free space at the end of the window. */
uInt wsize = s->w_size;
@@ -1418,35 +1508,11 @@ local void fill_window(s)
*/
if (s->strstart >= wsize+MAX_DIST(s)) {
- zmemcpy(s->window, s->window+wsize, (unsigned)wsize);
+ zmemcpy(s->window, s->window+wsize, (unsigned)wsize - more);
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). 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;
-#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);
-#endif
+ slide_hash(s);
more += wsize;
}
if (s->strm->avail_in == 0) break;
@@ -1552,70 +1618,195 @@ local void fill_window(s)
if (s->strm->avail_out == 0) return (last) ? finish_started : need_more; \
}
+/* Maximum stored block length in deflate format (not including header). */
+#define MAX_STORED 65535
+
+/* Minimum of a and b. */
+#define MIN(a, b) ((a) > (b) ? (b) : (a))
+
/* ===========================================================================
* Copy without compression as much as possible from the input stream, return
* the current block state.
- * 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 from
- * window to pending_buf.
+ *
+ * In case deflateParams() is used to later switch to a non-zero compression
+ * level, s->matches (otherwise unused when storing) keeps track of the number
+ * of hash table slides to perform. If s->matches is 1, then one hash table
+ * slide will be done when switching. If s->matches is 2, the maximum value
+ * allowed here, then the hash table will be cleared, since two or more slides
+ * is the same as a clear.
+ *
+ * deflate_stored() is written to minimize the number of times an input byte is
+ * copied. It is most efficient with large input and output buffers, which
+ * maximizes the opportunites to have a single copy from next_in to next_out.
*/
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:
+ /* Smallest worthy block size when not flushing or finishing. By default
+ * this is 32K. This can be as small as 507 bytes for memLevel == 1. For
+ * large input and output buffers, the stored block size will be larger.
*/
- 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;
- }
+ unsigned min_block = MIN(s->pending_buf_size - 5, s->w_size);
- /* Copy as much as possible from input to output: */
- for (;;) {
- /* Fill the window as much as possible: */
- if (s->lookahead <= 1) {
-
- Assert(s->strstart < s->w_size+MAX_DIST(s) ||
- s->block_start >= (long)s->w_size, "slide too late");
+ /* Copy as many min_block or larger stored blocks directly to next_out as
+ * possible. If flushing, copy the remaining available input to next_out as
+ * stored blocks, if there is enough space.
+ */
+ unsigned len, left, have, last = 0;
+ unsigned used = s->strm->avail_in;
+ do {
+ /* Set len to the maximum size block that we can copy directly with the
+ * available input data and output space. Set left to how much of that
+ * would be copied from what's left in the window.
+ */
+ len = MAX_STORED; /* maximum deflate stored block length */
+ have = (s->bi_valid + 42) >> 3; /* number of header bytes */
+ if (s->strm->avail_out < have) /* need room for header */
+ break;
+ /* maximum stored block length that will fit in avail_out: */
+ have = s->strm->avail_out - have;
+ left = s->strstart - s->block_start; /* bytes left in window */
+ if (len > (ulg)left + s->strm->avail_in)
+ len = left + s->strm->avail_in; /* limit len to the input */
+ if (len > have)
+ len = have; /* limit len to the output */
+ if (left > len)
+ left = len; /* limit window pull to len */
+
+ /* If the stored block would be less than min_block in length, or if
+ * unable to copy all of the available input when flushing, then try
+ * copying to the window and the pending buffer instead. Also don't
+ * write an empty block when flushing -- deflate() does that.
+ */
+ if (len < min_block && ((len == 0 && flush != Z_FINISH) ||
+ flush == Z_NO_FLUSH ||
+ len - left != s->strm->avail_in))
+ break;
- fill_window(s);
- if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
+ /* Make a dummy stored block in pending to get the header bytes,
+ * including any pending bits. This also updates the debugging counts.
+ */
+ last = flush == Z_FINISH && len - left == s->strm->avail_in ? 1 : 0;
+ _tr_stored_block(s, (char *)0, 0L, last);
+
+ /* Replace the lengths in the dummy stored block with len. */
+ s->pending_buf[s->pending - 4] = len;
+ s->pending_buf[s->pending - 3] = len >> 8;
+ s->pending_buf[s->pending - 2] = ~len;
+ s->pending_buf[s->pending - 1] = ~len >> 8;
+
+ /* Write the stored block header bytes. */
+ flush_pending(s->strm);
+
+ /* Update debugging counts for the data about to be copied. */
+#ifdef ZLIB_DEBUG
+ s->compressed_len += len << 3;
+ s->bits_sent += len << 3;
+#endif
- if (s->lookahead == 0) break; /* flush the current block */
+ /* Copy uncompressed bytes from the window to next_out. */
+ if (left) {
+ zmemcpy(s->strm->next_out, s->window + s->block_start, left);
+ s->strm->next_out += left;
+ s->strm->avail_out -= left;
+ s->strm->total_out += left;
+ s->block_start += left;
+ len -= left;
}
- Assert(s->block_start >= 0L, "block gone");
-
- 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;
- 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;
- FLUSH_BLOCK(s, 0);
+
+ /* Copy uncompressed bytes directly from next_in to next_out, updating
+ * the check value.
+ */
+ if (len) {
+ read_buf(s->strm, s->strm->next_out, len);
+ s->strm->next_out += len;
+ s->strm->avail_out -= len;
+ s->strm->total_out += len;
}
- /* Flush if we may have to slide, otherwise block_start may become
- * negative and the data will be gone:
+ } while (last == 0);
+
+ /* Update the sliding window with the last s->w_size bytes of the copied
+ * data, or append all of the copied data to the existing window if less
+ * than s->w_size bytes were copied. Also update the number of bytes to
+ * insert in the hash tables, in the event that deflateParams() switches to
+ * a non-zero compression level.
+ */
+ used -= s->strm->avail_in; /* number of input bytes directly copied */
+ if (used) {
+ /* If any input was used, then no unused input remains in the window,
+ * therefore s->block_start == s->strstart.
*/
- if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
- FLUSH_BLOCK(s, 0);
+ if (used >= s->w_size) { /* supplant the previous history */
+ s->matches = 2; /* clear hash */
+ zmemcpy(s->window, s->strm->next_in - s->w_size, s->w_size);
+ s->strstart = s->w_size;
}
+ else {
+ if (s->window_size - s->strstart <= used) {
+ /* Slide the window down. */
+ s->strstart -= s->w_size;
+ zmemcpy(s->window, s->window + s->w_size, s->strstart);
+ if (s->matches < 2)
+ s->matches++; /* add a pending slide_hash() */
+ }
+ zmemcpy(s->window + s->strstart, s->strm->next_in - used, used);
+ s->strstart += used;
+ }
+ s->block_start = s->strstart;
+ s->insert += MIN(used, s->w_size - s->insert);
}
- s->insert = 0;
- if (flush == Z_FINISH) {
- FLUSH_BLOCK(s, 1);
+
+ /* If the last block was written to next_out, then done. */
+ if (last)
return finish_done;
+
+ /* If flushing and all input has been consumed, then done. */
+ if (flush != Z_NO_FLUSH && flush != Z_FINISH &&
+ s->strm->avail_in == 0 && (long)s->strstart == s->block_start)
+ return block_done;
+
+ /* Fill the window with any remaining input. */
+ have = s->window_size - s->strstart - 1;
+ if (s->strm->avail_in > have && s->block_start >= (long)s->w_size) {
+ /* Slide the window down. */
+ s->block_start -= s->w_size;
+ s->strstart -= s->w_size;
+ zmemcpy(s->window, s->window + s->w_size, s->strstart);
+ if (s->matches < 2)
+ s->matches++; /* add a pending slide_hash() */
+ have += s->w_size; /* more space now */
}
- if ((long)s->strstart > s->block_start)
- FLUSH_BLOCK(s, 0);
- return block_done;
+ if (have > s->strm->avail_in)
+ have = s->strm->avail_in;
+ if (have) {
+ read_buf(s->strm, s->window + s->strstart, have);
+ s->strstart += have;
+ }
+
+ /* There was not enough avail_out to write a complete worthy or flushed
+ * stored block to next_out. Write a stored block to pending instead, if we
+ * have enough input for a worthy block, or if flushing and there is enough
+ * room for the remaining input as a stored block in the pending buffer.
+ */
+ have = (s->bi_valid + 42) >> 3; /* number of header bytes */
+ /* maximum stored block length that will fit in pending: */
+ have = MIN(s->pending_buf_size - have, MAX_STORED);
+ min_block = MIN(have, s->w_size);
+ left = s->strstart - s->block_start;
+ if (left >= min_block ||
+ ((left || flush == Z_FINISH) && flush != Z_NO_FLUSH &&
+ s->strm->avail_in == 0 && left <= have)) {
+ len = MIN(left, have);
+ last = flush == Z_FINISH && s->strm->avail_in == 0 &&
+ len == left ? 1 : 0;
+ _tr_stored_block(s, (charf *)s->window + s->block_start, len, last);
+ s->block_start += len;
+ flush_pending(s->strm);
+ }
+
+ /* We've done all we can with the available input and output. */
+ return last ? finish_started : need_more;
}
/* ===========================================================================
@@ -1892,7 +2083,7 @@ local block_state deflate_rle(s, flush)
prev == *++scan && prev == *++scan &&
prev == *++scan && prev == *++scan &&
scan < strend);
- s->match_length = MAX_MATCH - (int)(strend - scan);
+ s->match_length = MAX_MATCH - (uInt)(strend - scan);
if (s->match_length > s->lookahead)
s->match_length = s->lookahead;
}