zfs/lib/libspl/os/linux/getmntany.c

163 lines
3.7 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Copyright 2006 Ricardo Correia. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1988 AT&T */
/* All Rights Reserved */
#include <stdio.h>
#include <string.h>
#include <mntent.h>
#include <sys/errno.h>
#include <sys/mnttab.h>
#include <sys/types.h>
#include <sys/sysmacros.h>
#include <sys/stat.h>
#include <unistd.h>
#define BUFSIZE (MNT_LINE_MAX + 2)
static __thread char buf[BUFSIZE];
#define DIFF(xx) ( \
(mrefp->xx != NULL) && \
(mgetp->xx == NULL || strcmp(mrefp->xx, mgetp->xx) != 0))
int
getmntany(FILE *fp, struct mnttab *mgetp, struct mnttab *mrefp)
{
int ret;
while (
((ret = _sol_getmntent(fp, mgetp)) == 0) && (
DIFF(mnt_special) || DIFF(mnt_mountp) ||
DIFF(mnt_fstype) || DIFF(mnt_mntopts))) { }
return (ret);
}
int
_sol_getmntent(FILE *fp, struct mnttab *mgetp)
{
struct mntent mntbuf;
struct mntent *ret;
ret = getmntent_r(fp, &mntbuf, buf, BUFSIZE);
if (ret != NULL) {
mgetp->mnt_special = mntbuf.mnt_fsname;
mgetp->mnt_mountp = mntbuf.mnt_dir;
mgetp->mnt_fstype = mntbuf.mnt_type;
mgetp->mnt_mntopts = mntbuf.mnt_opts;
return (0);
}
if (feof(fp))
return (-1);
return (MNT_TOOLONG);
}
static int
getextmntent_impl(FILE *fp, struct extmnttab *mp, int len)
{
int ret;
struct stat64 st;
ret = _sol_getmntent(fp, (struct mnttab *)mp);
if (ret == 0) {
if (stat64(mp->mnt_mountp, &st) != 0) {
mp->mnt_major = 0;
mp->mnt_minor = 0;
return (ret);
}
mp->mnt_major = major(st.st_dev);
mp->mnt_minor = minor(st.st_dev);
}
return (ret);
}
int
getextmntent(const char *path, struct extmnttab *entry, struct stat64 *statbuf)
{
struct stat64 st;
FILE *fp;
int match;
if (strlen(path) >= MAXPATHLEN) {
(void) fprintf(stderr, "invalid object; pathname too long\n");
return (-1);
}
/*
* Search for the path in /proc/self/mounts. Rather than looking for the
* specific path, which can be fooled by non-standard paths (i.e. ".."
* or "//"), we stat() the path and search for the corresponding
* (major,minor) device pair.
*/
if (stat64(path, statbuf) != 0) {
(void) fprintf(stderr, "cannot open '%s': %s\n",
path, strerror(errno));
return (-1);
}
if ((fp = fopen(MNTTAB, "re")) == NULL) {
(void) fprintf(stderr, "cannot open %s\n", MNTTAB);
return (-1);
}
/*
* Search for the given (major,minor) pair in the mount table.
*/
match = 0;
while (getextmntent_impl(fp, entry, sizeof (*entry)) == 0) {
if (makedev(entry->mnt_major, entry->mnt_minor) ==
statbuf->st_dev) {
match = 1;
break;
}
}
(void) fclose(fp);
if (!match) {
(void) fprintf(stderr, "cannot find mountpoint for '%s'\n",
path);
return (-1);
}
if (stat64(entry->mnt_mountp, &st) != 0) {
entry->mnt_major = 0;
entry->mnt_minor = 0;
return (-1);
}
return (0);
}