e2fsprogs/old_e2fsprogs/ext2fs/ismounted.c - codeaurora/busybox - Gitiles

 /* vi: set sw=4 ts=4: */
 /*
  * ismounted.c --- Check to see if the filesystem was mounted
  *
  * Copyright (C) 1995,1996,1997,1998,1999,2000 Theodore Ts'o.
  *
  * %Begin-Header%
  * This file may be redistributed under the terms of the GNU Public
  * License.
  * %End-Header%
  */

 #include <stdio.h>
 #if HAVE_UNISTD_H
 #include <unistd.h>
 #endif
 #if HAVE_ERRNO_H
 #include <errno.h>
 #endif
 #include <fcntl.h>
 #ifdef HAVE_LINUX_FD_H
 #include <linux/fd.h>
 #endif
 #ifdef HAVE_MNTENT_H
 #include <mntent.h>
 #endif
 #ifdef HAVE_GETMNTINFO
 #include <paths.h>
 #include <sys/param.h>
 #include <sys/mount.h>
 #endif /* HAVE_GETMNTINFO */
 #include <string.h>
 #include <sys/stat.h>

 #include "ext2_fs.h"
 #include "ext2fs.h"

 #ifdef HAVE_MNTENT_H
 /*
  * Helper function which checks a file in /etc/mtab format to see if a
  * filesystem is mounted.  Returns an error if the file doesn't exist
  * or can't be opened.
  */
 static errcode_t check_mntent_file(const char *mtab_file, const char *file,
 				   int *mount_flags, char *mtpt, int mtlen)
 {
 	struct mntent	*mnt;
 	struct stat	st_buf;
 	errcode_t	retval = 0;
 	dev_t		file_dev=0, file_rdev=0;
 	ino_t		file_ino=0;
 	FILE		*f;
 	int		fd;

 	*mount_flags = 0;
 	if ((f = setmntent (mtab_file, "r")) == NULL)
 		return errno;
 	if (stat(file, &st_buf) == 0) {
 		if (S_ISBLK(st_buf.st_mode)) {
 #ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
 			file_rdev = st_buf.st_rdev;
 #endif	/* __GNU__ */
 		} else {
 			file_dev = st_buf.st_dev;
 			file_ino = st_buf.st_ino;
 		}
 	}
 	while ((mnt = getmntent (f)) != NULL) {
 		if (strcmp(file, mnt->mnt_fsname) == 0)
 			break;
 		if (stat(mnt->mnt_fsname, &st_buf) == 0) {
 			if (S_ISBLK(st_buf.st_mode)) {
 #ifndef __GNU__
 				if (file_rdev && (file_rdev == st_buf.st_rdev))
 					break;
 #endif	/* __GNU__ */
 			} else {
 				if (file_dev && ((file_dev == st_buf.st_dev) &&
 						 (file_ino == st_buf.st_ino)))
 					break;
 			}
 		}
 	}

 	if (mnt == 0) {
 #ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
 		/*
 		 * Do an extra check to see if this is the root device.  We
 		 * can't trust /etc/mtab, and /proc/mounts will only list
 		 * /dev/root for the root filesystem.  Argh.  Instead we
 		 * check if the given device has the same major/minor number
 		 * as the device that the root directory is on.
 		 */
 		if (file_rdev && stat("/", &st_buf) == 0) {
 			if (st_buf.st_dev == file_rdev) {
 				*mount_flags = EXT2_MF_MOUNTED;
 				if (mtpt)
 					strncpy(mtpt, "/", mtlen);
 				goto is_root;
 			}
 		}
 #endif	/* __GNU__ */
 		goto errout;
 	}
 #ifndef __GNU__ /* The GNU hurd is deficient; what else is new? */
 	/* Validate the entry in case /etc/mtab is out of date */
 	/*
 	 * We need to be paranoid, because some broken distributions
 	 * (read: Slackware) don't initialize /etc/mtab before checking
 	 * all of the non-root filesystems on the disk.
 	 */
 	if (stat(mnt->mnt_dir, &st_buf) < 0) {
 		retval = errno;
 		if (retval == ENOENT) {
 #ifdef DEBUG
 			printf("Bogus entry in %s!  (%s does not exist)\n",
 			       mtab_file, mnt->mnt_dir);
 #endif /* DEBUG */
 			retval = 0;
 		}
 		goto errout;
 	}
 	if (file_rdev && (st_buf.st_dev != file_rdev)) {
 #ifdef DEBUG
 		printf("Bogus entry in %s!  (%s not mounted on %s)\n",
 		       mtab_file, file, mnt->mnt_dir);
 #endif /* DEBUG */
 		goto errout;
 	}
 #endif /* __GNU__ */
 	*mount_flags = EXT2_MF_MOUNTED;

 #ifdef MNTOPT_RO
 	/* Check to see if the ro option is set */
 	if (hasmntopt(mnt, MNTOPT_RO))
 		*mount_flags |= EXT2_MF_READONLY;
 #endif

 	if (mtpt)
 		strncpy(mtpt, mnt->mnt_dir, mtlen);
 	/*
 	 * Check to see if we're referring to the root filesystem.
 	 * If so, do a manual check to see if we can open /etc/mtab
 	 * read/write, since if the root is mounted read/only, the
 	 * contents of /etc/mtab may not be accurate.
 	 */
 	if (LONE_CHAR(mnt->mnt_dir, '/')) {
 is_root:
 #define TEST_FILE "/.ismount-test-file"
 		*mount_flags |= EXT2_MF_ISROOT;
 		fd = open(TEST_FILE, O_RDWR|O_CREAT);
 		if (fd < 0) {
 			if (errno == EROFS)
 				*mount_flags |= EXT2_MF_READONLY;
 		} else
 			close(fd);
 		(void) unlink(TEST_FILE);
 	}
 	retval = 0;
 errout:
 	endmntent (f);
 	return retval;
 }

 static errcode_t check_mntent(const char *file, int *mount_flags,
 			      char *mtpt, int mtlen)
 {
 	errcode_t	retval;

 #ifdef DEBUG
 	retval = check_mntent_file("/tmp/mtab", file, mount_flags,
 				   mtpt, mtlen);
 	if (retval == 0)
 		return 0;
 #endif /* DEBUG */
 #ifdef __linux__
 	retval = check_mntent_file("/proc/mounts", file, mount_flags,
 				   mtpt, mtlen);
 	if (retval == 0 && (*mount_flags != 0))
 		return 0;
 #endif /* __linux__ */
 #if defined(MOUNTED) || defined(_PATH_MOUNTED)
 #ifndef MOUNTED
 #define MOUNTED _PATH_MOUNTED
 #endif /* MOUNTED */
 	retval = check_mntent_file(MOUNTED, file, mount_flags, mtpt, mtlen);
 	return retval;
 #else
 	*mount_flags = 0;
 	return 0;
 #endif /* defined(MOUNTED) || defined(_PATH_MOUNTED) */
 }

 #else
 #if defined(HAVE_GETMNTINFO)

 static errcode_t check_getmntinfo(const char *file, int *mount_flags,
 				  char *mtpt, int mtlen)
 {
 	struct statfs *mp;
 	int    len, n;
 	const  char   *s1;
 	char	*s2;

 	n = getmntinfo(&mp, MNT_NOWAIT);
 	if (n == 0)
 		return errno;

 	len = sizeof(_PATH_DEV) - 1;
 	s1 = file;
 	if (strncmp(_PATH_DEV, s1, len) == 0)
 		s1 += len;

 	*mount_flags = 0;
 	while (--n >= 0) {
 		s2 = mp->f_mntfromname;
 		if (strncmp(_PATH_DEV, s2, len) == 0) {
 			s2 += len - 1;
 			*s2 = 'r';
 		}
 		if (strcmp(s1, s2) == 0 || strcmp(s1, &s2[1]) == 0) {
 			*mount_flags = EXT2_MF_MOUNTED;
 			break;
 		}
 		++mp;
 	}
 	if (mtpt)
 		strncpy(mtpt, mp->f_mntonname, mtlen);
 	return 0;
 }
 #endif /* HAVE_GETMNTINFO */
 #endif /* HAVE_MNTENT_H */

 /*
  * Check to see if we're dealing with the swap device.
  */
 static int is_swap_device(const char *file)
 {
 	FILE		*f;
 	char		buf[1024], *cp;
 	dev_t		file_dev;
 	struct stat	st_buf;
 	int		ret = 0;

 	file_dev = 0;
 #ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
 	if ((stat(file, &st_buf) == 0) &&
 	    S_ISBLK(st_buf.st_mode))
 		file_dev = st_buf.st_rdev;
 #endif	/* __GNU__ */

 	if (!(f = fopen("/proc/swaps", "r")))
 		return 0;
 	/* Skip the first line */
 	fgets(buf, sizeof(buf), f);
 	while (!feof(f)) {
 		if (!fgets(buf, sizeof(buf), f))
 			break;
 		if ((cp = strchr(buf, ' ')) != NULL)
 			*cp = 0;
 		if ((cp = strchr(buf, '\t')) != NULL)
 			*cp = 0;
 		if (strcmp(buf, file) == 0) {
 			ret++;
 			break;
 		}
 #ifndef __GNU__
 		if (file_dev && (stat(buf, &st_buf) == 0) &&
 		    S_ISBLK(st_buf.st_mode) &&
 		    file_dev == st_buf.st_rdev) {
 			ret++;
 			break;
 		}
 #endif	/* __GNU__ */
 	}
 	fclose(f);
 	return ret;
 }


 /*
  * ext2fs_check_mount_point() returns 1 if the device is mounted, 0
  * otherwise.  If mtpt is non-NULL, the directory where the device is
  * mounted is copied to where mtpt is pointing, up to mtlen
  * characters.
  */
 #ifdef __TURBOC__
 # pragma argsused
 #endif
 errcode_t ext2fs_check_mount_point(const char *device, int *mount_flags,
 				  char *mtpt, int mtlen)
 {
 	if (is_swap_device(device)) {
 		*mount_flags = EXT2_MF_MOUNTED | EXT2_MF_SWAP;
 		strncpy(mtpt, "<swap>", mtlen);
 		return 0;
 	}
 #ifdef HAVE_MNTENT_H
 	return check_mntent(device, mount_flags, mtpt, mtlen);
 #else
 #ifdef HAVE_GETMNTINFO
 	return check_getmntinfo(device, mount_flags, mtpt, mtlen);
 #else
 #ifdef __GNUC__
  #warning "Can't use getmntent or getmntinfo to check for mounted filesystems!"
 #endif
 	*mount_flags = 0;
 	return 0;
 #endif /* HAVE_GETMNTINFO */
 #endif /* HAVE_MNTENT_H */
 }

 /*
  * ext2fs_check_if_mounted() sets the mount_flags EXT2_MF_MOUNTED,
  * EXT2_MF_READONLY, and EXT2_MF_ROOT
  *
  */
 errcode_t ext2fs_check_if_mounted(const char *file, int *mount_flags)
 {
 	return ext2fs_check_mount_point(file, mount_flags, NULL, 0);
 }

 #ifdef DEBUG
 int main(int argc, char **argv)
 {
 	int	retval, mount_flags;
 	char	mntpt[80];

 	if (argc < 2) {
 		fprintf(stderr, "Usage: %s device\n", argv[0]);
 		exit(1);
 	}

 	mntpt[0] = 0;
 	retval = ext2fs_check_mount_point(argv[1], &mount_flags,
 					  mntpt, sizeof(mntpt));
 	if (retval) {
 		com_err(argv[0], retval,
 			"while calling ext2fs_check_if_mounted");
 		exit(1);
 	}
 	printf("Device %s reports flags %02x\n", argv[1], mount_flags);
 	if (mount_flags & EXT2_MF_BUSY)
 		printf("\t%s is apparently in use.\n", argv[1]);
 	if (mount_flags & EXT2_MF_MOUNTED)
 		printf("\t%s is mounted.\n", argv[1]);
 	if (mount_flags & EXT2_MF_SWAP)
 		printf("\t%s is a swap device.\n", argv[1]);
 	if (mount_flags & EXT2_MF_READONLY)
 		printf("\t%s is read-only.\n", argv[1]);
 	if (mount_flags & EXT2_MF_ISROOT)
 		printf("\t%s is the root filesystem.\n", argv[1]);
 	if (mntpt[0])
 		printf("\t%s is mounted on %s.\n", argv[1], mntpt);
 	exit(0);
 }
 #endif /* DEBUG */
	/* vi: set sw=4 ts=4: */
	/*
	* ismounted.c --- Check to see if the filesystem was mounted
	*
	* Copyright (C) 1995,1996,1997,1998,1999,2000 Theodore Ts'o.
	*
	* %Begin-Header%
	* This file may be redistributed under the terms of the GNU Public
	* License.
	* %End-Header%
	*/

	#include <stdio.h>
	#if HAVE_UNISTD_H
	#include <unistd.h>
	#endif
	#if HAVE_ERRNO_H
	#include <errno.h>
	#endif
	#include <fcntl.h>
	#ifdef HAVE_LINUX_FD_H
	#include <linux/fd.h>
	#endif
	#ifdef HAVE_MNTENT_H
	#include <mntent.h>
	#endif
	#ifdef HAVE_GETMNTINFO
	#include <paths.h>
	#include <sys/param.h>
	#include <sys/mount.h>
	#endif /* HAVE_GETMNTINFO */
	#include <string.h>
	#include <sys/stat.h>

	#include "ext2_fs.h"
	#include "ext2fs.h"

	#ifdef HAVE_MNTENT_H
	/*
	* Helper function which checks a file in /etc/mtab format to see if a
	* filesystem is mounted. Returns an error if the file doesn't exist
	* or can't be opened.
	*/
	static errcode_t check_mntent_file(const char mtab_file, const char file,
	int mount_flags, char mtpt, int mtlen)
	{
	struct mntent *mnt;
	struct stat st_buf;
	errcode_t retval = 0;
	dev_t file_dev=0, file_rdev=0;
	ino_t file_ino=0;
	FILE *f;
	int fd;

	*mount_flags = 0;
	if ((f = setmntent (mtab_file, "r")) == NULL)
	return errno;
	if (stat(file, &st_buf) == 0) {
	if (S_ISBLK(st_buf.st_mode)) {
	#ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
	file_rdev = st_buf.st_rdev;
	#endif /* __GNU__ */
	} else {
	file_dev = st_buf.st_dev;
	file_ino = st_buf.st_ino;
	}
	}
	while ((mnt = getmntent (f)) != NULL) {
	if (strcmp(file, mnt->mnt_fsname) == 0)
	break;
	if (stat(mnt->mnt_fsname, &st_buf) == 0) {
	if (S_ISBLK(st_buf.st_mode)) {
	#ifndef __GNU__
	if (file_rdev && (file_rdev == st_buf.st_rdev))
	break;
	#endif /* __GNU__ */
	} else {
	if (file_dev && ((file_dev == st_buf.st_dev) &&
	(file_ino == st_buf.st_ino)))
	break;
	}
	}
	}

	if (mnt == 0) {
	#ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
	/*
	* Do an extra check to see if this is the root device. We
	* can't trust /etc/mtab, and /proc/mounts will only list
	* /dev/root for the root filesystem. Argh. Instead we
	* check if the given device has the same major/minor number
	* as the device that the root directory is on.
	*/
	if (file_rdev && stat("/", &st_buf) == 0) {
	if (st_buf.st_dev == file_rdev) {
	*mount_flags = EXT2_MF_MOUNTED;
	if (mtpt)
	strncpy(mtpt, "/", mtlen);
	goto is_root;
	}
	}
	#endif /* __GNU__ */
	goto errout;
	}
	#ifndef __GNU__ /* The GNU hurd is deficient; what else is new? */
	/* Validate the entry in case /etc/mtab is out of date */
	/*
	* We need to be paranoid, because some broken distributions
	* (read: Slackware) don't initialize /etc/mtab before checking
	* all of the non-root filesystems on the disk.
	*/
	if (stat(mnt->mnt_dir, &st_buf) < 0) {
	retval = errno;
	if (retval == ENOENT) {
	#ifdef DEBUG
	printf("Bogus entry in %s! (%s does not exist)\n",
	mtab_file, mnt->mnt_dir);
	#endif /* DEBUG */
	retval = 0;
	}
	goto errout;
	}
	if (file_rdev && (st_buf.st_dev != file_rdev)) {
	#ifdef DEBUG
	printf("Bogus entry in %s! (%s not mounted on %s)\n",
	mtab_file, file, mnt->mnt_dir);
	#endif /* DEBUG */
	goto errout;
	}
	#endif /* __GNU__ */
	*mount_flags = EXT2_MF_MOUNTED;

	#ifdef MNTOPT_RO
	/* Check to see if the ro option is set */
	if (hasmntopt(mnt, MNTOPT_RO))
	*mount_flags \|= EXT2_MF_READONLY;
	#endif

	if (mtpt)
	strncpy(mtpt, mnt->mnt_dir, mtlen);
	/*
	* Check to see if we're referring to the root filesystem.
	* If so, do a manual check to see if we can open /etc/mtab
	* read/write, since if the root is mounted read/only, the
	* contents of /etc/mtab may not be accurate.
	*/
	if (LONE_CHAR(mnt->mnt_dir, '/')) {
	is_root:
	#define TEST_FILE "/.ismount-test-file"
	*mount_flags \|= EXT2_MF_ISROOT;
	fd = open(TEST_FILE, O_RDWR\|O_CREAT);
	if (fd < 0) {
	if (errno == EROFS)
	*mount_flags \|= EXT2_MF_READONLY;
	} else
	close(fd);
	(void) unlink(TEST_FILE);
	}
	retval = 0;
	errout:
	endmntent (f);
	return retval;
	}

	static errcode_t check_mntent(const char file, int mount_flags,
	char *mtpt, int mtlen)
	{
	errcode_t retval;

	#ifdef DEBUG
	retval = check_mntent_file("/tmp/mtab", file, mount_flags,
	mtpt, mtlen);
	if (retval == 0)
	return 0;
	#endif /* DEBUG */
	#ifdef __linux__
	retval = check_mntent_file("/proc/mounts", file, mount_flags,
	mtpt, mtlen);
	if (retval == 0 && (*mount_flags != 0))
	return 0;
	#endif /* __linux__ */
	#if defined(MOUNTED) \|\| defined(_PATH_MOUNTED)
	#ifndef MOUNTED
	#define MOUNTED _PATH_MOUNTED
	#endif /* MOUNTED */
	retval = check_mntent_file(MOUNTED, file, mount_flags, mtpt, mtlen);
	return retval;
	#else
	*mount_flags = 0;
	return 0;
	#endif /* defined(MOUNTED) \|\| defined(_PATH_MOUNTED) */
	}

	#else
	#if defined(HAVE_GETMNTINFO)

	static errcode_t check_getmntinfo(const char file, int mount_flags,
	char *mtpt, int mtlen)
	{
	struct statfs *mp;
	int len, n;
	const char *s1;
	char *s2;

	n = getmntinfo(&mp, MNT_NOWAIT);
	if (n == 0)
	return errno;

	len = sizeof(_PATH_DEV) - 1;
	s1 = file;
	if (strncmp(_PATH_DEV, s1, len) == 0)
	s1 += len;

	*mount_flags = 0;
	while (--n >= 0) {
	s2 = mp->f_mntfromname;
	if (strncmp(_PATH_DEV, s2, len) == 0) {
	s2 += len - 1;
	*s2 = 'r';
	}
	if (strcmp(s1, s2) == 0 \|\| strcmp(s1, &s2[1]) == 0) {
	*mount_flags = EXT2_MF_MOUNTED;
	break;
	}
	++mp;
	}
	if (mtpt)
	strncpy(mtpt, mp->f_mntonname, mtlen);
	return 0;
	}
	#endif /* HAVE_GETMNTINFO */
	#endif /* HAVE_MNTENT_H */

	/*
	* Check to see if we're dealing with the swap device.
	*/
	static int is_swap_device(const char *file)
	{
	FILE *f;
	char buf[1024], *cp;
	dev_t file_dev;
	struct stat st_buf;
	int ret = 0;

	file_dev = 0;
	#ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
	if ((stat(file, &st_buf) == 0) &&
	S_ISBLK(st_buf.st_mode))
	file_dev = st_buf.st_rdev;
	#endif /* __GNU__ */

	if (!(f = fopen("/proc/swaps", "r")))
	return 0;
	/* Skip the first line */
	fgets(buf, sizeof(buf), f);
	while (!feof(f)) {
	if (!fgets(buf, sizeof(buf), f))
	break;
	if ((cp = strchr(buf, ' ')) != NULL)
	*cp = 0;
	if ((cp = strchr(buf, '\t')) != NULL)
	*cp = 0;
	if (strcmp(buf, file) == 0) {
	ret++;
	break;
	}
	#ifndef __GNU__
	if (file_dev && (stat(buf, &st_buf) == 0) &&
	S_ISBLK(st_buf.st_mode) &&
	file_dev == st_buf.st_rdev) {
	ret++;
	break;
	}
	#endif /* __GNU__ */
	}
	fclose(f);
	return ret;
	}


	/*
	* ext2fs_check_mount_point() returns 1 if the device is mounted, 0
	* otherwise. If mtpt is non-NULL, the directory where the device is
	* mounted is copied to where mtpt is pointing, up to mtlen
	* characters.
	*/
	#ifdef __TURBOC__
	# pragma argsused
	#endif
	errcode_t ext2fs_check_mount_point(const char device, int mount_flags,
	char *mtpt, int mtlen)
	{
	if (is_swap_device(device)) {
	*mount_flags = EXT2_MF_MOUNTED \| EXT2_MF_SWAP;
	strncpy(mtpt, "<swap>", mtlen);
	return 0;
	}
	#ifdef HAVE_MNTENT_H
	return check_mntent(device, mount_flags, mtpt, mtlen);
	#else
	#ifdef HAVE_GETMNTINFO
	return check_getmntinfo(device, mount_flags, mtpt, mtlen);
	#else
	#ifdef __GNUC__
	#warning "Can't use getmntent or getmntinfo to check for mounted filesystems!"
	#endif
	*mount_flags = 0;
	return 0;
	#endif /* HAVE_GETMNTINFO */
	#endif /* HAVE_MNTENT_H */
	}

	/*
	* ext2fs_check_if_mounted() sets the mount_flags EXT2_MF_MOUNTED,
	* EXT2_MF_READONLY, and EXT2_MF_ROOT
	*
	*/
	errcode_t ext2fs_check_if_mounted(const char file, int mount_flags)
	{
	return ext2fs_check_mount_point(file, mount_flags, NULL, 0);
	}

	#ifdef DEBUG
	int main(int argc, char **argv)
	{
	int retval, mount_flags;
	char mntpt[80];

	if (argc < 2) {
	fprintf(stderr, "Usage: %s device\n", argv[0]);
	exit(1);
	}

	mntpt[0] = 0;
	retval = ext2fs_check_mount_point(argv[1], &mount_flags,
	mntpt, sizeof(mntpt));
	if (retval) {
	com_err(argv[0], retval,
	"while calling ext2fs_check_if_mounted");
	exit(1);
	}
	printf("Device %s reports flags %02x\n", argv[1], mount_flags);
	if (mount_flags & EXT2_MF_BUSY)
	printf("\t%s is apparently in use.\n", argv[1]);
	if (mount_flags & EXT2_MF_MOUNTED)
	printf("\t%s is mounted.\n", argv[1]);
	if (mount_flags & EXT2_MF_SWAP)
	printf("\t%s is a swap device.\n", argv[1]);
	if (mount_flags & EXT2_MF_READONLY)
	printf("\t%s is read-only.\n", argv[1]);
	if (mount_flags & EXT2_MF_ISROOT)
	printf("\t%s is the root filesystem.\n", argv[1]);
	if (mntpt[0])
	printf("\t%s is mounted on %s.\n", argv[1], mntpt);
	exit(0);
	}
	#endif /* DEBUG */