cannam@128: /* compress.c -- compress a memory buffer
cannam@128:  * Copyright (C) 1995-2005 Jean-loup Gailly.
cannam@128:  * For conditions of distribution and use, see copyright notice in zlib.h
cannam@128:  */
cannam@128: 
cannam@128: /* @(#) $Id$ */
cannam@128: 
cannam@128: #define ZLIB_INTERNAL
cannam@128: #include "zlib.h"
cannam@128: 
cannam@128: /* ===========================================================================
cannam@128:      Compresses the source buffer into the destination buffer. The level
cannam@128:    parameter has the same meaning as in deflateInit.  sourceLen is the byte
cannam@128:    length of the source buffer. Upon entry, destLen is the total size of the
cannam@128:    destination buffer, which must be at least 0.1% larger than sourceLen plus
cannam@128:    12 bytes. Upon exit, destLen is the actual size of the compressed buffer.
cannam@128: 
cannam@128:      compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
cannam@128:    memory, Z_BUF_ERROR if there was not enough room in the output buffer,
cannam@128:    Z_STREAM_ERROR if the level parameter is invalid.
cannam@128: */
cannam@128: int ZEXPORT compress2 (dest, destLen, source, sourceLen, level)
cannam@128:     Bytef *dest;
cannam@128:     uLongf *destLen;
cannam@128:     const Bytef *source;
cannam@128:     uLong sourceLen;
cannam@128:     int level;
cannam@128: {
cannam@128:     z_stream stream;
cannam@128:     int err;
cannam@128: 
cannam@128:     stream.next_in = (z_const Bytef *)source;
cannam@128:     stream.avail_in = (uInt)sourceLen;
cannam@128: #ifdef MAXSEG_64K
cannam@128:     /* Check for source > 64K on 16-bit machine: */
cannam@128:     if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
cannam@128: #endif
cannam@128:     stream.next_out = dest;
cannam@128:     stream.avail_out = (uInt)*destLen;
cannam@128:     if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
cannam@128: 
cannam@128:     stream.zalloc = (alloc_func)0;
cannam@128:     stream.zfree = (free_func)0;
cannam@128:     stream.opaque = (voidpf)0;
cannam@128: 
cannam@128:     err = deflateInit(&stream, level);
cannam@128:     if (err != Z_OK) return err;
cannam@128: 
cannam@128:     err = deflate(&stream, Z_FINISH);
cannam@128:     if (err != Z_STREAM_END) {
cannam@128:         deflateEnd(&stream);
cannam@128:         return err == Z_OK ? Z_BUF_ERROR : err;
cannam@128:     }
cannam@128:     *destLen = stream.total_out;
cannam@128: 
cannam@128:     err = deflateEnd(&stream);
cannam@128:     return err;
cannam@128: }
cannam@128: 
cannam@128: /* ===========================================================================
cannam@128:  */
cannam@128: int ZEXPORT compress (dest, destLen, source, sourceLen)
cannam@128:     Bytef *dest;
cannam@128:     uLongf *destLen;
cannam@128:     const Bytef *source;
cannam@128:     uLong sourceLen;
cannam@128: {
cannam@128:     return compress2(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION);
cannam@128: }
cannam@128: 
cannam@128: /* ===========================================================================
cannam@128:      If the default memLevel or windowBits for deflateInit() is changed, then
cannam@128:    this function needs to be updated.
cannam@128:  */
cannam@128: uLong ZEXPORT compressBound (sourceLen)
cannam@128:     uLong sourceLen;
cannam@128: {
cannam@128:     return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) +
cannam@128:            (sourceLen >> 25) + 13;
cannam@128: }