getvfsbyname.c revision 121667 
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)
35static 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: head/lib/libc/gen/getvfsbyname.c 121667 2003-10-29 10:45:01Z tjr $");
39
40#include <sys/param.h>
41#include <sys/mount.h>
42#include <sys/sysctl.h>
43#include <errno.h>
44#include <stdlib.h>
45#include <string.h>
46
47/*
48 * Given a filesystem name, determine if it is resident in the kernel,
49 * and if it is resident, return its xvfsconf structure.
50 */
51int
52getvfsbyname(fsname, vfcp)
53	const char *fsname;
54	struct xvfsconf *vfcp;
55{
56	struct xvfsconf *xvfsp;
57	size_t buflen;
58	int cnt, i;
59
60	if (sysctlbyname("vfs.conflist", NULL, &buflen, NULL, 0) < 0)
61		return (-1);
62	xvfsp = malloc(buflen);
63	if (xvfsp == NULL)
64		return (-1);
65	if (sysctlbyname("vfs.conflist", xvfsp, &buflen, NULL, 0) < 0) {
66		free(xvfsp);
67		return (-1);
68	}
69	cnt = buflen / sizeof(struct xvfsconf);
70	for (i = 0; i < cnt; i++) {
71		if (strcmp(fsname, xvfsp[i].vfc_name) == 0) {
72			memcpy(vfcp, xvfsp + i, sizeof(struct xvfsconf));
73			free(xvfsp);
74			return (0);
75		}
76	}
77	free(xvfsp);
78	errno = ENOENT;
79	return (-1);
80}
81