xref: /netbsd-src/lib/libutil/opendisk.c (revision 5e4c038a45edbc7d63b7c2daa76e29f88b64a4e3)
1 /*	$NetBSD: opendisk.c,v 1.9 2001/12/10 22:41:52 lukem Exp $	*/
2 
3 /*-
4  * Copyright (c) 1997 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Luke Mewburn.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 #if defined(LIBC_SCCS) && !defined(lint)
41 __RCSID("$NetBSD: opendisk.c,v 1.9 2001/12/10 22:41:52 lukem Exp $");
42 #endif
43 
44 #include <sys/param.h>
45 
46 #include <assert.h>
47 #include <errno.h>
48 #include <fcntl.h>
49 #include <util.h>
50 #include <paths.h>
51 #include <stdio.h>
52 #include <string.h>
53 
54 int
55 opendisk(const char *path, int flags, char *buf, size_t buflen, int iscooked)
56 {
57 	int f, rawpart;
58 
59 	if (buf == NULL) {
60 		errno = EFAULT;
61 		return (-1);
62 	}
63 	snprintf(buf, buflen, "%s", path);
64 
65 	if ((flags & O_CREAT) != 0) {
66 		errno = EINVAL;
67 		return (-1);
68 	}
69 
70 	rawpart = getrawpartition();
71 	if (rawpart < 0)
72 		return (-1);	/* sysctl(3) in getrawpartition sets errno */
73 
74 	f = open(buf, flags);
75 	if (f != -1 || errno != ENOENT)
76 		return (f);
77 
78 	snprintf(buf, buflen, "%s%c", path, 'a' + rawpart);
79 	f = open(buf, flags);
80 	if (f != -1 || errno != ENOENT)
81 		return (f);
82 
83 	if (strchr(path, '/') != NULL)
84 		return (-1);
85 
86 	snprintf(buf, buflen, "%s%s%s", _PATH_DEV, iscooked ? "" : "r", path);
87 	f = open(buf, flags);
88 	if (f != -1 || errno != ENOENT)
89 		return (f);
90 
91 	snprintf(buf, buflen, "%s%s%s%c", _PATH_DEV, iscooked ? "" : "r", path,
92 	    'a' + rawpart);
93 	f = open(buf, flags);
94 	return (f);
95 }
96