Chris@43: /* compress.c -- compress a memory buffer
Chris@43:  * Copyright (C) 1995-2005 Jean-loup Gailly.
Chris@43:  * For conditions of distribution and use, see copyright notice in zlib.h
Chris@43:  */
Chris@43: 
Chris@43: /* @(#) $Id$ */
Chris@43: 
Chris@43: #define ZLIB_INTERNAL
Chris@43: #include "zlib.h"
Chris@43: 
Chris@43: /* ===========================================================================
Chris@43:      Compresses the source buffer into the destination buffer. The level
Chris@43:    parameter has the same meaning as in deflateInit.  sourceLen is the byte
Chris@43:    length of the source buffer. Upon entry, destLen is the total size of the
Chris@43:    destination buffer, which must be at least 0.1% larger than sourceLen plus
Chris@43:    12 bytes. Upon exit, destLen is the actual size of the compressed buffer.
Chris@43: 
Chris@43:      compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
Chris@43:    memory, Z_BUF_ERROR if there was not enough room in the output buffer,
Chris@43:    Z_STREAM_ERROR if the level parameter is invalid.
Chris@43: */
Chris@43: int ZEXPORT compress2 (dest, destLen, source, sourceLen, level)
Chris@43:     Bytef *dest;
Chris@43:     uLongf *destLen;
Chris@43:     const Bytef *source;
Chris@43:     uLong sourceLen;
Chris@43:     int level;
Chris@43: {
Chris@43:     z_stream stream;
Chris@43:     int err;
Chris@43: 
Chris@43:     stream.next_in = (z_const Bytef *)source;
Chris@43:     stream.avail_in = (uInt)sourceLen;
Chris@43: #ifdef MAXSEG_64K
Chris@43:     /* Check for source > 64K on 16-bit machine: */
Chris@43:     if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
Chris@43: #endif
Chris@43:     stream.next_out = dest;
Chris@43:     stream.avail_out = (uInt)*destLen;
Chris@43:     if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
Chris@43: 
Chris@43:     stream.zalloc = (alloc_func)0;
Chris@43:     stream.zfree = (free_func)0;
Chris@43:     stream.opaque = (voidpf)0;
Chris@43: 
Chris@43:     err = deflateInit(&stream, level);
Chris@43:     if (err != Z_OK) return err;
Chris@43: 
Chris@43:     err = deflate(&stream, Z_FINISH);
Chris@43:     if (err != Z_STREAM_END) {
Chris@43:         deflateEnd(&stream);
Chris@43:         return err == Z_OK ? Z_BUF_ERROR : err;
Chris@43:     }
Chris@43:     *destLen = stream.total_out;
Chris@43: 
Chris@43:     err = deflateEnd(&stream);
Chris@43:     return err;
Chris@43: }
Chris@43: 
Chris@43: /* ===========================================================================
Chris@43:  */
Chris@43: int ZEXPORT compress (dest, destLen, source, sourceLen)
Chris@43:     Bytef *dest;
Chris@43:     uLongf *destLen;
Chris@43:     const Bytef *source;
Chris@43:     uLong sourceLen;
Chris@43: {
Chris@43:     return compress2(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION);
Chris@43: }
Chris@43: 
Chris@43: /* ===========================================================================
Chris@43:      If the default memLevel or windowBits for deflateInit() is changed, then
Chris@43:    this function needs to be updated.
Chris@43:  */
Chris@43: uLong ZEXPORT compressBound (sourceLen)
Chris@43:     uLong sourceLen;
Chris@43: {
Chris@43:     return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) +
Chris@43:            (sourceLen >> 25) + 13;
Chris@43: }