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zlib 1.2.0

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This commit is contained in:
Mark Adler
2011-09-09 23:21:47 -07:00
parent a383133c4e
commit 7c2a874e50
77 changed files with 7236 additions and 2478 deletions
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54
deflate.c
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@@ -1,5 +1,5 @@
/* deflate.c -- compress data using the deflation algorithm
* Copyright (C) 1995-2002 Jean-loup Gailly.
* Copyright (C) 1995-2003 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@@ -52,7 +52,7 @@
#include "deflate.h"
const char deflate_copyright[] =
" deflate 1.1.4 Copyright 1995-2002 Jean-loup Gailly ";
" deflate 1.2.0 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
@@ -212,7 +212,7 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
{
deflate_state *s;
int noheader = 0;
static const char* my_version = ZLIB_VERSION;
static const char my_version[] = ZLIB_VERSION;
ushf *overlay;
/* We overlay pending_buf and d_buf+l_buf. This works since the average
@@ -273,6 +273,7 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
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;
@@ -299,10 +300,12 @@ int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
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->noheader && strm->state->status != INIT_STATE))
return Z_STREAM_ERROR;
s = strm->state;
strm->adler = adler32(strm->adler, dictionary, dictLength);
if (!s->noheader)
strm->adler = adler32(strm->adler, dictionary, dictLength);
if (length < MIN_MATCH) return Z_OK;
if (length > MAX_DIST(s)) {
@@ -394,6 +397,47 @@ int ZEXPORT deflateParams(strm, level, 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 noheader.
* 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