xref: /netbsd-src/lib/libutil/getfsspecname.c (revision ba65fde2d7fefa7d39838fa5fa855e62bd606b5e)
1 /*	$NetBSD: getfsspecname.c,v 1.4 2013/01/01 18:32:17 dsl Exp $	*/
2 
3 /*-
4  * Copyright (c) 2012 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Christos Zoulas.
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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 #include <sys/cdefs.h>
32 __RCSID("$NetBSD: getfsspecname.c,v 1.4 2013/01/01 18:32:17 dsl Exp $");
33 
34 #include <sys/types.h>
35 #include <sys/ioctl.h>
36 #include <sys/sysctl.h>
37 #include <sys/disk.h>
38 
39 #include <stdio.h>
40 #include <vis.h>
41 #include <string.h>
42 #include <fstab.h>
43 #include <fcntl.h>
44 #include <stdlib.h>
45 #include <errno.h>
46 #include <unistd.h>
47 #include <util.h>
48 
49 #define COMPAT_DKWEDGE	/* To be removed */
50 
51 const char *
52 getfsspecname(char *buf, size_t bufsiz, const char *name)
53 {
54 	static const int mib[] = { CTL_HW, HW_DISKNAMES };
55 	static const unsigned int miblen = __arraycount(mib);
56 	char *drives, *dk;
57 	size_t len;
58 	int fd, savee;
59 	char *vname;
60 
61 	drives = NULL;
62 	vname = NULL;
63 	if (strncasecmp(name, "NAME=", 5) != 0) {
64 #ifdef COMPAT_DKWEDGE
65 		/*
66 		 * We try to open the disk name, and if we fail with EBUSY
67 		 * we use the name as the label to find the wedge.
68 		 */
69 		char rbuf[MAXPATHLEN];
70 		if (name[0] == '/') {
71 			if (getdiskrawname(rbuf, sizeof(rbuf), name) != NULL) {
72 				if ((fd = open(rbuf, O_RDONLY)) == -1) {
73 					if (errno == EBUSY) {
74 						name = strrchr(name, '/') + 1;
75 						goto search;
76 					}
77 				} else
78 					close(fd);
79 			}
80 		}
81 #endif
82 		strlcpy(buf, name, bufsiz);
83 		return buf;
84 	} else
85 		name += 5;
86 
87 #ifdef COMPAT_DKWEDGE
88 search:
89 #endif
90 	vname = malloc(strlen(name) * 4 + 1);
91 	if (vname == NULL) {
92 		savee = errno;
93 		strlcpy(buf, "malloc failed", bufsiz);
94 		goto out;
95 	}
96 
97 	strunvis(vname, name);
98 
99 	if (sysctl(mib, miblen, NULL, &len, NULL, 0) == -1) {
100 		savee = errno;
101 		strlcpy(buf, "sysctl hw.disknames failed", bufsiz);
102 		goto out;
103 	}
104 
105 	drives = malloc(len);
106 	if (drives == NULL) {
107 		savee = errno;
108 		strlcpy(buf, "malloc failed", bufsiz);
109 		goto out;
110 	}
111 	if (sysctl(mib, miblen, drives, &len, NULL, 0) == -1) {
112 		savee = errno;
113 		strlcpy(buf, "sysctl hw.disknames failed", bufsiz);
114 		goto out;
115 	}
116 
117 	for (dk = strtok(drives, " "); dk != NULL; dk = strtok(NULL, " ")) {
118 		struct dkwedge_info dkw;
119 		if (strncmp(dk, "dk", 2) != 0)
120 			continue;
121 		fd = opendisk(dk, O_RDONLY, buf, bufsiz, 0);
122 		if (fd == -1)
123 			continue;
124 		if (ioctl(fd, DIOCGWEDGEINFO, &dkw) == -1) {
125 			savee = errno;
126 			snprintf(buf, bufsiz, "%s: getwedgeinfo", dk);
127 			(void)close(fd);
128 			goto out;
129 		}
130 		(void)close(fd);
131 		if (strcmp(vname, (char *)dkw.dkw_wname) == 0) {
132 			char *p = strstr(buf, "/rdk");
133 			if (p++ == NULL)
134 				return buf;
135 			strcpy(p, p + 1);
136 			free(drives);
137 			free(vname);
138 			return buf;
139 		}
140 	}
141 	savee = ESRCH;
142 	snprintf(buf, bufsiz, "no match for `%s'", vname);
143 out:
144 	free(drives);
145 	free(vname);
146 	errno = savee;
147 	return NULL;
148 }
149