dvander@159: /* compress.c -- compress a memory buffer
dvander@159:  * Copyright (C) 1995-2003 Jean-loup Gailly.
dvander@159:  * For conditions of distribution and use, see copyright notice in zlib.h
dvander@159:  */
dvander@159: 
dvander@159: /* @(#) $Id$ */
dvander@159: 
dvander@159: #define ZLIB_INTERNAL
dvander@159: #include "zlib.h"
dvander@159: 
dvander@159: /* ===========================================================================
dvander@159:      Compresses the source buffer into the destination buffer. The level
dvander@159:    parameter has the same meaning as in deflateInit.  sourceLen is the byte
dvander@159:    length of the source buffer. Upon entry, destLen is the total size of the
dvander@159:    destination buffer, which must be at least 0.1% larger than sourceLen plus
dvander@159:    12 bytes. Upon exit, destLen is the actual size of the compressed buffer.
dvander@159: 
dvander@159:      compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
dvander@159:    memory, Z_BUF_ERROR if there was not enough room in the output buffer,
dvander@159:    Z_STREAM_ERROR if the level parameter is invalid.
dvander@159: */
dvander@159: int ZEXPORT compress2 (dest, destLen, source, sourceLen, level)
dvander@159:     Bytef *dest;
dvander@159:     uLongf *destLen;
dvander@159:     const Bytef *source;
dvander@159:     uLong sourceLen;
dvander@159:     int level;
dvander@159: {
dvander@159:     z_stream stream;
dvander@159:     int err;
dvander@159: 
dvander@159:     stream.next_in = (Bytef*)source;
dvander@159:     stream.avail_in = (uInt)sourceLen;
dvander@159: #ifdef MAXSEG_64K
dvander@159:     /* Check for source > 64K on 16-bit machine: */
dvander@159:     if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
dvander@159: #endif
dvander@159:     stream.next_out = dest;
dvander@159:     stream.avail_out = (uInt)*destLen;
dvander@159:     if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
dvander@159: 
dvander@159:     stream.zalloc = (alloc_func)0;
dvander@159:     stream.zfree = (free_func)0;
dvander@159:     stream.opaque = (voidpf)0;
dvander@159: 
dvander@159:     err = deflateInit(&stream, level);
dvander@159:     if (err != Z_OK) return err;
dvander@159: 
dvander@159:     err = deflate(&stream, Z_FINISH);
dvander@159:     if (err != Z_STREAM_END) {
dvander@159:         deflateEnd(&stream);
dvander@159:         return err == Z_OK ? Z_BUF_ERROR : err;
dvander@159:     }
dvander@159:     *destLen = stream.total_out;
dvander@159: 
dvander@159:     err = deflateEnd(&stream);
dvander@159:     return err;
dvander@159: }
dvander@159: 
dvander@159: /* ===========================================================================
dvander@159:  */
dvander@159: int ZEXPORT compress (dest, destLen, source, sourceLen)
dvander@159:     Bytef *dest;
dvander@159:     uLongf *destLen;
dvander@159:     const Bytef *source;
dvander@159:     uLong sourceLen;
dvander@159: {
dvander@159:     return compress2(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION);
dvander@159: }
dvander@159: 
dvander@159: /* ===========================================================================
dvander@159:      If the default memLevel or windowBits for deflateInit() is changed, then
dvander@159:    this function needs to be updated.
dvander@159:  */
dvander@159: uLong ZEXPORT compressBound (sourceLen)
dvander@159:     uLong sourceLen;
dvander@159: {
dvander@159:     return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) + 11;
dvander@159: }