diff options
Diffstat (limited to 'compat/zlib/compress.c')
| -rw-r--r-- | compat/zlib/compress.c | 80 | 
1 files changed, 80 insertions, 0 deletions
| diff --git a/compat/zlib/compress.c b/compat/zlib/compress.c new file mode 100644 index 0000000..6e97626 --- /dev/null +++ b/compat/zlib/compress.c @@ -0,0 +1,80 @@ +/* compress.c -- compress a memory buffer + * Copyright (C) 1995-2005 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* @(#) $Id$ */ + +#define ZLIB_INTERNAL +#include "zlib.h" + +/* =========================================================================== +     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 (dest, destLen, source, sourceLen, level) +    Bytef *dest; +    uLongf *destLen; +    const Bytef *source; +    uLong sourceLen; +    int level; +{ +    z_stream stream; +    int err; + +    stream.next_in = (z_const 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)0; +    stream.zfree = (free_func)0; +    stream.opaque = (voidpf)0; + +    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 (dest, destLen, source, sourceLen) +    Bytef *dest; +    uLongf *destLen; +    const Bytef *source; +    uLong sourceLen; +{ +    return compress2(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION); +} + +/* =========================================================================== +     If the default memLevel or windowBits for deflateInit() is changed, then +   this function needs to be updated. + */ +uLong ZEXPORT compressBound (sourceLen) +    uLong sourceLen; +{ +    return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) + +           (sourceLen >> 25) + 13; +} | 
