freebsd-skq/lib/libc/gen/getvfsbyname.c
Alan Somers 822f5b1dad style changes to getvfsbyname
Reported by:	markj
Sponsored by:	The FreeBSD Foundation
2019-07-17 19:41:44 +00:00

92 lines
3.1 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1995
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__SCCSID("@(#)kvm_getvfsbyname.c 8.1 (Berkeley) 4/3/95");
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/sysctl.h>
#include <errno.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
/*
* fusefs(5) file systems may have a "subtype" which gets appended to
* statfs(2)'s f_fstypename field on a per-mount basis. Allow getvfsbyname to
* match either the full "fusefs.foobar" or the more general "fusefs".
*/
static bool
are_fusefs(const char *fsname, const char *vfc_name)
{
const static char fusefs[] = "fusefs";
const static char fusefs_dot[] = "fusefs.";
return (strncmp(fsname, fusefs_dot, sizeof(fusefs_dot) - 1) == 0 &&
strcmp(fusefs, vfc_name) == 0);
}
/*
* Given a filesystem name, determine if it is resident in the kernel,
* and if it is resident, return its xvfsconf structure.
*/
int
getvfsbyname(const char *fsname, struct xvfsconf *vfcp)
{
struct xvfsconf *xvfsp;
size_t buflen;
int cnt, i;
if (sysctlbyname("vfs.conflist", NULL, &buflen, NULL, 0) < 0)
return (-1);
xvfsp = malloc(buflen);
if (xvfsp == NULL)
return (-1);
if (sysctlbyname("vfs.conflist", xvfsp, &buflen, NULL, 0) < 0) {
free(xvfsp);
return (-1);
}
cnt = buflen / sizeof(struct xvfsconf);
for (i = 0; i < cnt; i++) {
if (strcmp(fsname, xvfsp[i].vfc_name) == 0 ||
are_fusefs(fsname, xvfsp[i].vfc_name)) {
memcpy(vfcp, xvfsp + i, sizeof(struct xvfsconf));
free(xvfsp);
return (0);
}
}
free(xvfsp);
errno = ENOENT;
return (-1);
}