xref: /illumos-gate/usr/src/uts/common/fs/zfs/gzip.c (revision ddb365bfc9e868ad24ccdcb0dc91af18b10df082)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <sys/debug.h>
28 #include <sys/types.h>
29 #include <sys/zmod.h>
30 
31 #ifdef _KERNEL
32 #include <sys/systm.h>
33 #else
34 #include <strings.h>
35 #endif
36 
37 size_t
38 gzip_compress(void *s_start, void *d_start, size_t s_len, size_t d_len, int n)
39 {
40 	size_t dstlen = d_len;
41 
42 	ASSERT(d_len <= s_len);
43 
44 	if (z_compress_level(d_start, &dstlen, s_start, s_len, n) != Z_OK) {
45 		if (d_len != s_len)
46 			return (s_len);
47 
48 		bcopy(s_start, d_start, s_len);
49 		return (s_len);
50 	}
51 
52 	return (dstlen);
53 }
54 
55 /*ARGSUSED*/
56 int
57 gzip_decompress(void *s_start, void *d_start, size_t s_len, size_t d_len, int n)
58 {
59 	size_t dstlen = d_len;
60 
61 	ASSERT(d_len >= s_len);
62 
63 	if (z_uncompress(d_start, &dstlen, s_start, s_len) != Z_OK)
64 		return (-1);
65 
66 	return (0);
67 }
68