xref: /freebsd/lib/libc/gen/getvfsbyname.c (revision a0ee8cc6)
1 /*
2  * Copyright (c) 1995
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #if defined(LIBC_SCCS) && !defined(lint)
31 static char sccsid[] = "@(#)kvm_getvfsbyname.c	8.1 (Berkeley) 4/3/95";
32 #endif /* LIBC_SCCS and not lint */
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/mount.h>
38 #include <sys/sysctl.h>
39 #include <errno.h>
40 #include <stdlib.h>
41 #include <string.h>
42 
43 /*
44  * Given a filesystem name, determine if it is resident in the kernel,
45  * and if it is resident, return its xvfsconf structure.
46  */
47 int
48 getvfsbyname(const char *fsname, struct xvfsconf *vfcp)
49 {
50 	struct xvfsconf *xvfsp;
51 	size_t buflen;
52 	int cnt, i;
53 
54 	if (sysctlbyname("vfs.conflist", NULL, &buflen, NULL, 0) < 0)
55 		return (-1);
56 	xvfsp = malloc(buflen);
57 	if (xvfsp == NULL)
58 		return (-1);
59 	if (sysctlbyname("vfs.conflist", xvfsp, &buflen, NULL, 0) < 0) {
60 		free(xvfsp);
61 		return (-1);
62 	}
63 	cnt = buflen / sizeof(struct xvfsconf);
64 	for (i = 0; i < cnt; i++) {
65 		if (strcmp(fsname, xvfsp[i].vfc_name) == 0) {
66 			memcpy(vfcp, xvfsp + i, sizeof(struct xvfsconf));
67 			free(xvfsp);
68 			return (0);
69 		}
70 	}
71 	free(xvfsp);
72 	errno = ENOENT;
73 	return (-1);
74 }
75