gzip.c revision 199767f8919635c4928607450d9e0abb932109ce
/*
* This file and its contents are supplied under the terms of the
* Common Development and Distribution License ("CDDL"), version 1.0.
* You may only use this file in accordance with the terms of version
* 1.0 of the CDDL.
*
* A full copy of the text of the CDDL should have accompanied this
* source. A copy of the CDDL is also available via the Internet at
* http://www.illumos.org/license/CDDL.
*/
/*
* Copyright 2015 Toomas Soome <tsoome@me.com>
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include <zlib.h>
#include <strings.h>
int gzip_decompress(void *, void *, size_t, size_t, int);
/*
* Uncompress the buffer 'src' into the buffer 'dst'. The caller must store
* the expected decompressed data size externally so it can be passed in.
* The resulting decompressed size is then returned through dstlen. This
* function return Z_OK on success, or another error code on failure.
*/
static int
z_uncompress(void *dst, size_t *dstlen, const void *src, size_t srclen)
{
z_stream zs;
int err;
bzero(&zs, sizeof (zs));
zs.next_in = (unsigned char *)src;
zs.avail_in = srclen;
zs.next_out = dst;
zs.avail_out = *dstlen;
/*
* Call inflateInit2() specifying a window size of DEF_WBITS
* with the 6th bit set to indicate that the compression format
* type (zlib or gzip) should be automatically detected.
*/
if ((err = inflateInit2(&zs, 15 | 0x20)) != Z_OK)
return (err);
if ((err = inflate(&zs, Z_FINISH)) != Z_STREAM_END) {
(void) inflateEnd(&zs);
return (err == Z_OK ? Z_BUF_ERROR : err);
}
*dstlen = zs.total_out;
return (inflateEnd(&zs));
}
int
gzip_decompress(void *s_start, void *d_start, size_t s_len, size_t d_len, int n)
{
size_t dstlen = d_len;
if (z_uncompress(d_start, &dstlen, s_start, s_len) != Z_OK)
return (-1);
return (0);
}