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/* @(#) $Id: compress.c,v 1.3 2001/12/27 21:00:17 jbj Exp $ */
/*
* Copyright (C) 1995-1998 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/**
* \file compress.c
* Compress a memory buffer.
*/
#include "zlib.h"
#include "zutil.h" /* XXX for zmemzero() */
/*@access z_streamp@*/
/* ========================================================================= */
/**
* Compresses the source buffer into the destination buffer. The level
* parameter has the same meaning as in deflateInit. sourceLen is the byte
* length of the source buffer. Upon entry, destLen is the total size of the
* destination buffer, which must be at least 0.1% larger than sourceLen plus
* 12 bytes. Upon exit, destLen is the actual size of the compressed buffer.
*
* compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
* memory, Z_BUF_ERROR if there was not enough room in the output buffer,
* Z_STREAM_ERROR if the level parameter is invalid.
*/
int ZEXPORT compress2 (Bytef *dest, uLongf *destLen, const Bytef *source, uLong sourceLen, int level)
{
z_stream stream;
int err;
zmemzero(&stream, sizeof(stream));
stream.next_in = (Bytef*)source;
stream.avail_in = (uInt)sourceLen;
#ifdef MAXSEG_64K
/* Check for source > 64K on 16-bit machine: */
if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
#endif
stream.next_out = dest;
stream.avail_out = (uInt)*destLen;
if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
stream.zalloc = (alloc_func)NULL;
stream.zfree = (free_func)NULL;
stream.opaque = (voidpf)NULL;
err = deflateInit(&stream, level);
if (err != Z_OK) return err;
err = deflate(&stream, Z_FINISH);
if (err != Z_STREAM_END) {
deflateEnd(&stream);
return err == Z_OK ? Z_BUF_ERROR : err;
}
*destLen = stream.total_out;
err = deflateEnd(&stream);
return err;
}
/* ========================================================================= */
int ZEXPORT compress (Bytef *dest, uLongf *destLen, const Bytef *source, uLong sourceLen)
{
return compress2(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION);
}
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