mirror of
https://github.com/GerbilSoft/zlib-ng.git
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ec6adfbfb0
* zconf.h.in wasn't including Windows.h, that is correct header to include definitions from BaseTsd.h, and such missing required type definition for ssize_t when compiling using MS Visual C++ * Various places need implicit casting to z_size_t to get around compatibility issues, this will truncate the result when ZLIB_COMPAT is defined, calling code should check for truncation. * Add ZLIB_COMPAT flag to nmake Makefile and use it to determine correct filenames instead of WITH_GZFILEOP
81 lines
2.8 KiB
C
81 lines
2.8 KiB
C
/* compress.c -- compress a memory buffer
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* Copyright (C) 1995-2005, 2014, 2016 Jean-loup Gailly, Mark Adler
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* For conditions of distribution and use, see copyright notice in zlib.h
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*/
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/* @(#) $Id$ */
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#define ZLIB_INTERNAL
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#if defined(ZLIB_COMPAT)
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# include "zlib.h"
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# define z_size_t unsigned long
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#else
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# include "zlib-ng.h"
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# define z_size_t size_t
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#endif
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/* ===========================================================================
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Compresses the source buffer into the destination buffer. The level
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parameter has the same meaning as in deflateInit. sourceLen is the byte
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length of the source buffer. Upon entry, destLen is the total size of the
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destination buffer, which must be at least 0.1% larger than sourceLen plus
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12 bytes. Upon exit, destLen is the actual size of the compressed buffer.
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compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
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memory, Z_BUF_ERROR if there was not enough room in the output buffer,
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Z_STREAM_ERROR if the level parameter is invalid.
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*/
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int ZEXPORT PREFIX(compress2)(unsigned char *dest, z_size_t *destLen, const unsigned char *source,
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z_size_t sourceLen, int level) {
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PREFIX3(stream) stream;
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int err;
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const unsigned int max = (unsigned int)-1;
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z_size_t left;
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left = *destLen;
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*destLen = 0;
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stream.zalloc = NULL;
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stream.zfree = NULL;
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stream.opaque = NULL;
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err = PREFIX(deflateInit)(&stream, level);
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if (err != Z_OK)
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return err;
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stream.next_out = dest;
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stream.avail_out = 0;
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stream.next_in = (const unsigned char *)source;
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stream.avail_in = 0;
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do {
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if (stream.avail_out == 0) {
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stream.avail_out = left > (unsigned long)max ? max : (unsigned int)left;
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left -= stream.avail_out;
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}
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if (stream.avail_in == 0) {
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stream.avail_in = sourceLen > (unsigned long)max ? max : (unsigned int)sourceLen;
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sourceLen -= stream.avail_in;
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}
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err = PREFIX(deflate)(&stream, sourceLen ? Z_NO_FLUSH : Z_FINISH);
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} while (err == Z_OK);
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*destLen = (z_size_t)stream.total_out;
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PREFIX(deflateEnd)(&stream);
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return err == Z_STREAM_END ? Z_OK : err;
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}
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/* ===========================================================================
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*/
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int ZEXPORT PREFIX(compress)(unsigned char *dest, z_size_t *destLen, const unsigned char *source, z_size_t sourceLen) {
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return PREFIX(compress2)(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION);
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}
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/* ===========================================================================
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If the default memLevel or windowBits for deflateInit() is changed, then
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this function needs to be updated.
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*/
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z_size_t ZEXPORT PREFIX(compressBound)(z_size_t sourceLen) {
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return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) + (sourceLen >> 25) + 13;
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}
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