xref: /freebsd/lib/libc/gen/getvfsbyname.c (revision ea8d448a923f0d68d7ecf1d2a0583c7d17bdee4e)
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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char sccsid[] = "@(#)kvm_getvfsbyname.c	8.1 (Berkeley) 4/3/95";
36 #endif /* LIBC_SCCS and not lint */
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include <sys/param.h>
41 #include <sys/mount.h>
42 #include <sys/sysctl.h>
43 #include <errno.h>
44 
45 /*
46  * Given a filesystem name, determine if it is resident in the kernel,
47  * and if it is resident, return its vfsconf structure.
48  */
49 getvfsbyname(fsname, vfcp)
50 	const char *fsname;
51 	struct vfsconf *vfcp;
52 {
53 #ifdef	__NETBSD_SYSCALLS
54 	errno = ENOSYS;
55 #else
56 	int name[4], maxtypenum, cnt;
57 	size_t buflen;
58 
59 	name[0] = CTL_VFS;
60 	name[1] = VFS_GENERIC;
61 	name[2] = VFS_MAXTYPENUM;
62 	buflen = 4;
63 	if (sysctl(name, 3, &maxtypenum, &buflen, (void *)0, (size_t)0) < 0)
64 		return (-1);
65 	name[2] = VFS_CONF;
66 	buflen = sizeof *vfcp;
67 	for (cnt = 0; cnt < maxtypenum; cnt++) {
68 		name[3] = cnt;
69 		if (sysctl(name, 4, vfcp, &buflen, (void *)0, (size_t)0) < 0) {
70 			if (errno != EOPNOTSUPP)
71 				return (-1);
72 			continue;
73 		}
74 		if (!strcmp(fsname, vfcp->vfc_name))
75 			return (0);
76 	}
77 	errno = ENOENT;
78 #endif
79 	return (-1);
80 }
81