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/* Copyright (C) 1998-2003, 2004 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <assert.h>
#include <errno.h>
#include <mntent.h>
#include <paths.h>
#include <stdbool.h>
#include <stdio_ext.h>
#include <string.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/statfs.h>
#include <sys/statvfs.h>
#include "linux_fsinfo.h"
#ifndef STATFS
# define STATFS statfs
# define STATVFS statvfs
# define INTERNAL_STATVFS __internal_statvfs
#endif
void
INTERNAL_STATVFS (const char *name, struct STATVFS *buf,
struct STATFS *fsbuf, struct stat64 *st)
{
/* Now fill in the fields we have information for. */
buf->f_bsize = fsbuf->f_bsize;
/* Linux has the f_frsize size only in later version of the kernel.
If the value is not filled in use f_bsize. */
buf->f_frsize = fsbuf->f_frsize ?: fsbuf->f_bsize;
buf->f_blocks = fsbuf->f_blocks;
buf->f_bfree = fsbuf->f_bfree;
buf->f_bavail = fsbuf->f_bavail;
buf->f_files = fsbuf->f_files;
buf->f_ffree = fsbuf->f_ffree;
if (sizeof (buf->f_fsid) == sizeof (fsbuf->f_fsid))
buf->f_fsid = (fsbuf->f_fsid.__val[0]
| ((unsigned long int) fsbuf->f_fsid.__val[1]
<< (8 * (sizeof (buf->f_fsid)
- sizeof (fsbuf->f_fsid.__val[0])))));
else
/* We cannot help here. The statvfs element is not large enough to
contain both words of the statfs f_fsid field. */
buf->f_fsid = fsbuf->f_fsid.__val[0];
#ifdef _STATVFSBUF_F_UNUSED
buf->__f_unused = 0;
#endif
buf->f_namemax = fsbuf->f_namelen;
memset (buf->__f_spare, '\0', 6 * sizeof (int));
/* What remains to do is to fill the fields f_favail and f_flag. */
/* XXX I have no idea how to compute f_favail. Any idea??? */
buf->f_favail = buf->f_ffree;
/* Determining the flags is tricky. We have to read /proc/mounts or
the /etc/mtab file and search for the entry which matches the given
file. The way we can test for matching filesystem is using the
device number. */
buf->f_flag = 0;
if (st != NULL)
{
struct mntent mntbuf;
FILE *mtab;
const char *fsname = NULL;
const char *fsname2 = NULL;
bool success = false;
/* Map the filesystem type we got from the statfs call to a string. */
switch (fsbuf->f_type)
{
case EXT2_SUPER_MAGIC:
fsname = "ext3";
fsname2 = "ext2";
break;
case DEVPTS_SUPER_MAGIC:
fsname= "devpts";
break;
case SHMFS_SUPER_MAGIC:
fsname = "tmpfs";
break;
case PROC_SUPER_MAGIC:
fsname = "proc";
break;
case USBDEVFS_SUPER_MAGIC:
fsname = "usbdevfs";
break;
case AUTOFS_SUPER_MAGIC:
fsname = "autofs";
break;
case NFS_SUPER_MAGIC:
fsname = "nfs";
break;
}
mtab = __setmntent ("/proc/mounts", "r");
if (mtab == NULL)
mtab = __setmntent (_PATH_MOUNTED, "r");
if (mtab != NULL)
{
char tmpbuf[1024];
/* No locking needed. */
(void) __fsetlocking (mtab, FSETLOCKING_BYCALLER);
again:
while (__getmntent_r (mtab, &mntbuf, tmpbuf, sizeof (tmpbuf)))
{
/* In a first round we look for a given mount point, if
we have a name. */
if (name != NULL && strcmp (name, mntbuf.mnt_dir) != 0)
continue;
/* We need to look at the entry only if the filesystem
name matches. If we have a filesystem name. */
else if (fsname != NULL
&& strcmp (fsname, mntbuf.mnt_type) != 0
&& (fsname2 == NULL
|| strcmp (fsname2, mntbuf.mnt_type) != 0))
continue;
/* Find out about the device the current entry is for. */
struct stat64 fsst;
if (stat64 (mntbuf.mnt_dir, &fsst) >= 0
&& st->st_dev == fsst.st_dev)
{
/* Bingo, we found the entry for the device FD is on.
Now interpret the option string. */
char *cp = mntbuf.mnt_opts;
char *opt;
while ((opt = strsep (&cp, ",")) != NULL)
if (strcmp (opt, "ro") == 0)
buf->f_flag |= ST_RDONLY;
else if (strcmp (opt, "nosuid") == 0)
buf->f_flag |= ST_NOSUID;
else if (strcmp (opt, "noexec") == 0)
buf->f_flag |= ST_NOEXEC;
else if (strcmp (opt, "nodev") == 0)
buf->f_flag |= ST_NODEV;
else if (strcmp (opt, "sync") == 0)
buf->f_flag |= ST_SYNCHRONOUS;
else if (strcmp (opt, "mand") == 0)
buf->f_flag |= ST_MANDLOCK;
else if (strcmp (opt, "noatime") == 0)
buf->f_flag |= ST_NOATIME;
else if (strcmp (opt, "nodiratime") == 0)
buf->f_flag |= ST_NODIRATIME;
/* We can stop looking for more entries. */
success = true;
break;
}
}
/* Maybe the kernel names for the filesystems changed or the
statvfs call got a name which was not the mount point.
Check again, this time without checking for name matches
first. */
if (! success && (name != NULL || fsname != NULL))
{
if (name != NULL)
/* Try without a mount point name. */
name = NULL;
else
{
/* Try without a filesystem name. */
assert (fsname != NULL);
fsname = fsname2 = NULL;
}
/* It is not strictly allowed to use rewind here. But
this code is part of the implementation so it is
acceptable. */
rewind (mtab);
goto again;
}
/* Close the file. */
__endmntent (mtab);
}
}
}
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