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 2008 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #include <sys/modctl.h>
28 #include <sys/zmod.h>
29
30 #include <zlib.h>
31 #include <zutil.h>
32
33 /*
34 * Uncompress the buffer 'src' into the buffer 'dst'. The caller must store
35 * the expected decompressed data size externally so it can be passed in.
36 * The resulting decompressed size is then returned through dstlen. This
37 * function return Z_OK on success, or another error code on failure.
38 */
39 int
z_uncompress(void * dst,size_t * dstlen,const void * src,size_t srclen)40 z_uncompress(void *dst, size_t *dstlen, const void *src, size_t srclen)
41 {
42 z_stream zs;
43 int err;
44
45 bzero(&zs, sizeof (zs));
46 zs.next_in = (uchar_t *)src;
47 zs.avail_in = srclen;
48 zs.next_out = dst;
49 zs.avail_out = *dstlen;
50
51 /*
52 * Call inflateInit2() specifying a window size of DEF_WBITS
53 * with the 6th bit set to indicate that the compression format
54 * type (zlib or gzip) should be automatically detected.
55 */
56 if ((err = inflateInit2(&zs, DEF_WBITS | 0x20)) != Z_OK)
57 return (err);
58
59 if ((err = inflate(&zs, Z_FINISH)) != Z_STREAM_END) {
60 (void) inflateEnd(&zs);
61 return (err == Z_OK ? Z_BUF_ERROR : err);
62 }
63
64 *dstlen = zs.total_out;
65 return (inflateEnd(&zs));
66 }
67
68 int
z_compress_level(void * dst,size_t * dstlen,const void * src,size_t srclen,int level)69 z_compress_level(void *dst, size_t *dstlen, const void *src, size_t srclen,
70 int level)
71 {
72
73 z_stream zs;
74 int err;
75
76 bzero(&zs, sizeof (zs));
77 zs.next_in = (uchar_t *)src;
78 zs.avail_in = srclen;
79 zs.next_out = dst;
80 zs.avail_out = *dstlen;
81
82 if ((err = deflateInit(&zs, level)) != Z_OK)
83 return (err);
84
85 if ((err = deflate(&zs, Z_FINISH)) != Z_STREAM_END) {
86 (void) deflateEnd(&zs);
87 return (err == Z_OK ? Z_BUF_ERROR : err);
88 }
89
90 *dstlen = zs.total_out;
91 return (deflateEnd(&zs));
92 }
93
94 int
z_compress(void * dst,size_t * dstlen,const void * src,size_t srclen)95 z_compress(void *dst, size_t *dstlen, const void *src, size_t srclen)
96 {
97 return (z_compress_level(dst, dstlen, src, srclen,
98 Z_DEFAULT_COMPRESSION));
99 }
100
101 /*
102 * Convert a zlib error code into a string error message.
103 */
104 const char *
z_strerror(int err)105 z_strerror(int err)
106 {
107 int i = Z_NEED_DICT - err;
108
109 if (i < 0 || i > Z_NEED_DICT - Z_VERSION_ERROR)
110 return ("unknown error");
111
112 return (zError(err));
113 }
114