xref: /openbsd-src/lib/libutil/opendisk.c (revision daf88648c0e349d5c02e1504293082072c981640)
1 /*	$OpenBSD: opendisk.c,v 1.4 2005/10/19 18:48:11 deraadt Exp $	*/
2 /*	$NetBSD: opendisk.c,v 1.4 1997/09/30 17:13:50 phil Exp $	*/
3 
4 /*-
5  * Copyright (c) 1997 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Luke Mewburn.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *        This product includes software developed by the NetBSD
22  *        Foundation, Inc. and its contributors.
23  * 4. Neither the name of The NetBSD Foundation nor the names of its
24  *    contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  */
39 
40 #include <sys/cdefs.h>
41 #include <sys/param.h>
42 
43 #include <errno.h>
44 #include <fcntl.h>
45 #include <paths.h>
46 #include <stdio.h>
47 #include <string.h>
48 
49 #include "util.h"
50 
51 int
52 opendisk(const char *path, int flags, char *buf, size_t buflen, int iscooked)
53 {
54 	int f, rawpart;
55 
56 	snprintf(buf, buflen, "%s", path);
57 
58 	if ((flags & O_CREAT) != 0) {
59 		errno = EINVAL;
60 		return (-1);
61 	}
62 
63 	rawpart = getrawpartition();
64 	if (rawpart < 0)
65 		return (-1);	/* sysctl(3) in getrawpartition sets errno */
66 
67 	f = open(buf, flags);
68 	if (f != -1 || errno != ENOENT)
69 		return (f);
70 
71 	snprintf(buf, buflen, "%s%c", path, 'a' + rawpart);
72 	f = open(buf, flags);
73 	if (f != -1 || errno != ENOENT)
74 		return (f);
75 
76 	if (strchr(path, '/') != NULL)
77 		return (-1);
78 
79 	snprintf(buf, buflen, "%s%s%s", _PATH_DEV, iscooked ? "" : "r", path);
80 	f = open(buf, flags);
81 	if (f != -1 || errno != ENOENT)
82 		return (f);
83 
84 	snprintf(buf, buflen, "%s%s%s%c", _PATH_DEV, iscooked ? "" : "r", path,
85 	    'a' + rawpart);
86 	f = open(buf, flags);
87 	return (f);
88 }
89