busybox/libbb/find_mount_point.c

76 lines
2.0 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdio.h>
#include <string.h>
#include "libbb.h"
#include <mntent.h>
/*
* Given a block device, find the mount table entry if that block device
* is mounted.
*
* Given any other file (or directory), find the mount table entry for its
* filesystem.
*/
extern struct mntent *find_mount_point(const char *name, const char *table)
{
struct stat s;
dev_t mountDevice;
FILE *mountTable;
struct mntent *mountEntry;
if (stat(name, &s) != 0)
return 0;
if ((s.st_mode & S_IFMT) == S_IFBLK)
mountDevice = s.st_rdev;
else
mountDevice = s.st_dev;
if ((mountTable = setmntent(table, "r")) == 0)
return 0;
while ((mountEntry = getmntent(mountTable)) != 0) {
if (strcmp(name, mountEntry->mnt_dir) == 0
|| strcmp(name, mountEntry->mnt_fsname) == 0) /* String match. */
break;
if (stat(mountEntry->mnt_fsname, &s) == 0 && s.st_rdev == mountDevice) /* Match the device. */
break;
if (stat(mountEntry->mnt_dir, &s) == 0 && s.st_dev == mountDevice) /* Match the directory's mount point. */
break;
}
endmntent(mountTable);
return mountEntry;
}
/* END CODE */
/*
Local Variables:
c-file-style: "linux"
c-basic-offset: 4
tab-width: 4
End:
*/