xref: /netbsd-src/lib/libutil/opendisk.c (revision 4472dbe5e3bd91ef2540bada7a7ca7384627ff9b)
1 /*	$NetBSD: opendisk.c,v 1.6 1999/09/20 04:48:07 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 1.6 1999/09/20 04:48:07 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(path, flags, buf, buflen, iscooked)
56 	const char *path;
57 	int	flags;
58 	char   *buf;
59 	size_t	buflen;
60 	int	iscooked;
61 {
62 	int f, rawpart;
63 
64 
65 	if (buf == NULL) {
66 		errno = EFAULT;
67 		return (-1);
68 	}
69 	snprintf(buf, buflen, "%s", path);
70 
71 	if ((flags & O_CREAT) != 0) {
72 		errno = EINVAL;
73 		return (-1);
74 	}
75 
76 	rawpart = getrawpartition();
77 	if (rawpart < 0)
78 		return (-1);	/* sysctl(3) in getrawpartition sets errno */
79 
80 	f = open(buf, flags);
81 	if (f != -1 || errno != ENOENT)
82 		return (f);
83 
84 	snprintf(buf, buflen, "%s%c", path, 'a' + rawpart);
85 	f = open(buf, flags);
86 	if (f != -1 || errno != ENOENT)
87 		return (f);
88 
89 	if (strchr(path, '/') != NULL)
90 		return (-1);
91 
92 	snprintf(buf, buflen, "%s%s%s", _PATH_DEV, iscooked ? "" : "r", path);
93 	f = open(buf, flags);
94 	if (f != -1 || errno != ENOENT)
95 		return (f);
96 
97 	snprintf(buf, buflen, "%s%s%s%c", _PATH_DEV, iscooked ? "" : "r", path,
98 	    'a' + rawpart);
99 	f = open(buf, flags);
100 	return (f);
101 }
102