113 lines
3.5 KiB
C
113 lines
3.5 KiB
C
#ifndef _SPL_ZMOD_H
|
|
#define _SPL_ZMOD_H
|
|
|
|
#include <linux/zlib.h>
|
|
|
|
/* NOTE: z_compress_level/z_uncompress are nearly identical copies of
|
|
* the compress2/uncompress functions provided by the official zlib
|
|
* package available at http://zlib.net/. The only changes made we to
|
|
* slightly adapt the functioned called to match the linux kernel
|
|
* implementation of zlib.
|
|
*/
|
|
|
|
/* ===========================================================================
|
|
* 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.
|
|
*/
|
|
static __inline__ int
|
|
z_compress_level(Byte *dest, uLong *destLen, const Byte *source,
|
|
uLong sourceLen, int level)
|
|
{
|
|
z_stream stream;
|
|
int err;
|
|
|
|
stream.next_in = (Byte *)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;
|
|
|
|
err = zlib_deflateInit(&stream, level);
|
|
if (err != Z_OK)
|
|
return err;
|
|
|
|
err = zlib_deflate(&stream, Z_FINISH);
|
|
if (err != Z_STREAM_END) {
|
|
zlib_deflateEnd(&stream);
|
|
return err == Z_OK ? Z_BUF_ERROR : err;
|
|
}
|
|
*destLen = stream.total_out;
|
|
|
|
err = zlib_deflateEnd(&stream);
|
|
return err;
|
|
} /* z_compress_level() */
|
|
|
|
/* ===========================================================================
|
|
* Decompresses the source buffer into the destination buffer. sourceLen is
|
|
* the byte length of the source buffer. Upon entry, destLen is the total
|
|
* size of the destination buffer, which must be large enough to hold the
|
|
* entire uncompressed data. (The size of the uncompressed data must have
|
|
* been saved previously by the compressor and transmitted to the decompressor
|
|
* by some mechanism outside the scope of this compression library.)
|
|
* Upon exit, destLen is the actual size of the compressed buffer.
|
|
* This function can be used to decompress a whole file at once if the
|
|
* input file is mmap'ed.
|
|
*
|
|
* uncompress 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, or Z_DATA_ERROR if the input data was corrupted.
|
|
*/
|
|
static __inline__ int
|
|
z_uncompress(Byte *dest, uLong *destLen, const Byte *source, uLong sourceLen)
|
|
{
|
|
z_stream stream;
|
|
int err;
|
|
|
|
stream.next_in = (Byte *)source;
|
|
stream.avail_in = (uInt)sourceLen;
|
|
/* Check for source > 64K on 16-bit machine: */
|
|
if ((uLong)stream.avail_in != sourceLen)
|
|
return Z_BUF_ERROR;
|
|
|
|
stream.next_out = dest;
|
|
stream.avail_out = (uInt)*destLen;
|
|
|
|
if ((uLong)stream.avail_out != *destLen)
|
|
return Z_BUF_ERROR;
|
|
|
|
err = zlib_inflateInit(&stream);
|
|
if (err != Z_OK)
|
|
return err;
|
|
|
|
err = zlib_inflate(&stream, Z_FINISH);
|
|
if (err != Z_STREAM_END) {
|
|
zlib_inflateEnd(&stream);
|
|
|
|
if (err == Z_NEED_DICT ||
|
|
(err == Z_BUF_ERROR && stream.avail_in == 0))
|
|
return Z_DATA_ERROR;
|
|
|
|
return err;
|
|
}
|
|
*destLen = stream.total_out;
|
|
|
|
err = zlib_inflateEnd(&stream);
|
|
return err;
|
|
} /* z_uncompress() */
|
|
|
|
#endif /* SPL_ZMOD_H */
|