Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk

things down a bit, fixed a number of funky corner cases, added support for
several new features (things like mount --move, mount --bind, lazy unounts,
automatic detection of loop mounts, and so on).  Probably broke several
other things, but it's fixable.  (Bang on it, tell me what doesn't work for
you...)

Note: you no longer need to say "-o loop".  It does that for you when
necessary.

Still need to add "user mount" support, which involves making mount suid.  Not
too hard to do under the new infrastructure, just haven't done it yet...

The previous code had the following notes, that belong in the version
control comments:

- * 3/21/1999   Charles P. Wright <cpwright@cpwright.com>
- *             searches through fstab when -a is passed
- *             will try mounting stuff with all fses when passed -t auto
- *
- * 1999-04-17  Dave Cinege...Rewrote -t auto. Fixed ro mtab.
- *
- * 1999-10-07  Erik Andersen <andersen@codepoet.org>.
- *              Rewrite of a lot of code. Removed mtab usage (I plan on
- *              putting it back as a compile-time option some time),
- *              major adjustments to option parsing, and some serious
- *              dieting all around.
- *
- * 1999-11-06  mtab support is back - andersee
- *
- * 2000-01-12   Ben Collins <bcollins@debian.org>, Borrowed utils-linux's
- *              mount to add loop support.
- *
- * 2000-04-30  Dave Cinege <dcinege@psychosis.com>
- *             Rewrote fstab while loop and lower mount section. Can now do
- *             single mounts from fstab. Can override fstab options for single
- *             mount. Common mount_one call for single mounts and 'all'. Fixed
- *             mtab updating and stale entries. Removed 'remount' default.
- *

12 files changed, 543 insertions, 922 deletions

diff --git a/coreutils/df.c b/coreutils/df.c
index ba2e7ccc9..9233fbbf1 100644
--- a/coreutils/df.c
+++ b/coreutils/df.c
@@ -130,7 +130,7 @@ extern int df_main(int argc, char **argv)
 			} else if (strcmp(device, "/dev/root") == 0) {
 				/* Adjusts device to be the real root device,
 				* or leaves device alone if it can't find it */
-				if ((device = find_real_root_device_name()) == NULL) {
+				if ((device = find_block_device("/")) == NULL) {
 					goto SET_ERROR;
 				}
 			}
diff --git a/include/libbb.h b/include/libbb.h
index d12860ca9..14670f026 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -132,11 +132,9 @@ extern int get_kernel_revision(void);
 
 extern int get_console_fd(void);
 extern struct mntent *find_mount_point(const char *name, const char *table);
-extern void write_mtab(char* blockDevice, char* directory,
-					   char* filesystemType, long flags, char* string_flags);
 extern void erase_mtab(const char * name);
 extern long *find_pid_by_name( const char* pidName);
-extern char *find_real_root_device_name(void);
+extern char *find_block_device(char *path);
 extern char *bb_get_line_from_file(FILE *file);
 extern char *bb_get_chomped_line_from_file(FILE *file);
 extern char *bb_get_chunk_from_file(FILE *file);
@@ -242,16 +240,14 @@ extern char *bb_askpass(int timeout, const char * prompt);
 extern int device_open(const char *device, int mode);
 
 extern int del_loop(const char *device);
-extern int set_loop(const char *device, const char *file, int offset, int *loopro);
-extern char *find_unused_loop_device (void);
-
+extern int set_loop(char **device, const char *file, int offset);
 
 #if (__GLIBC__ < 2)
 extern int vdprintf(int d, const char *format, va_list ap);
 #endif
 
 int nfsmount(const char *spec, const char *node, int *flags,
-	     char **extra_opts, char **mount_opts, int running_bg);
+	     char **mount_opts, int running_bg);
 
 /* Include our own copy of struct sysinfo to avoid binary compatability
  * problems with Linux 2.4, which changed things.  Grumble, grumble. */
@@ -452,6 +448,7 @@ typedef struct {
 	int ppid;
 #ifdef FEATURE_CPU_USAGE_PERCENTAGE
 	unsigned pcpu;
+	unsigned pscpu;
 	unsigned long stime, utime;
 #endif
 	char *cmd;
diff --git a/libbb/find_mount_point.c b/libbb/find_mount_point.c
index 83824de9e..eec738aea 100644
--- a/libbb/find_mount_point.c
+++ b/libbb/find_mount_point.c
@@ -48,7 +48,7 @@ extern struct mntent *find_mount_point(const char *name, const char *table)
 		mountDevice = s.st_dev;
 
 
-	if ((mountTable = setmntent(table, "r")) == 0)
+	if ((mountTable = setmntent(table ? : bb_path_mtab_file, "r")) == 0)
 		return 0;
 
 	while ((mountEntry = getmntent(mountTable)) != 0) {
diff --git a/libbb/find_root_device.c b/libbb/find_root_device.c
index 2600ce5e0..7ff65bb57 100644
--- a/libbb/find_root_device.c
+++ b/libbb/find_root_device.c
@@ -25,65 +25,25 @@
 #include <stdlib.h>
 #include "libbb.h"
 
-
-
-extern char *find_real_root_device_name(void)
+extern char *find_block_device(char *path)
 {
 	DIR *dir;
 	struct dirent *entry;
-	struct stat statBuf, rootStat;
-	char *fileName = NULL;
+	struct stat st;
 	dev_t dev;
-
-	if (stat("/", &rootStat) != 0)
-		bb_perror_msg("could not stat '/'");
-	else {
-		/* This check is here in case they pass in /dev name */
-		if ((rootStat.st_mode & S_IFMT) == S_IFBLK)
-			dev = rootStat.st_rdev;
-		else
-			dev = rootStat.st_dev;
-
-		dir = opendir("/dev");
-		if (!dir)
-			bb_perror_msg("could not open '/dev'");
-		else {
-			while((entry = readdir(dir)) != NULL) {
-				const char *myname = entry->d_name;
-				/* Must skip ".." since that is "/", and so we
-				 * would get a false positive on ".."  */
-				if (myname[0] == '.' && myname[1] == '.' && !myname[2])
-					continue;
-#ifdef CONFIG_FEATURE_DEVFS
-				/* if there is a link named /dev/root skip that too */
-				if (strcmp(myname, "root")==0)
-					continue;
-#endif
-				fileName = concat_path_file("/dev", myname);
-
-				/* Some char devices have the same dev_t as block
-				 * devices, so make sure this is a block device */
-				if (stat(fileName, &statBuf) == 0 &&
-						S_ISBLK(statBuf.st_mode)!=0 &&
-						statBuf.st_rdev == dev)
-					break;
-				free(fileName);
-				fileName=NULL;
-			}
-			closedir(dir);
+	char *retpath=NULL;
+
+	if(stat(path, &st) || !(dir = opendir("/dev"))) return NULL;
+	dev = (st.st_mode & S_IFMT) == S_IFBLK ? st.st_rdev : st.st_dev;
+	while((entry = readdir(dir)) != NULL) {
+		char devpath[PATH_MAX];
+		sprintf(devpath,"/dev/%s", entry->d_name);
+		if(!stat(devpath, &st) && S_ISBLK(st.st_mode) && st.st_rdev == dev) {
+			retpath = bb_xstrdup(devpath);
+			break;
 		}
 	}
-	if(fileName==NULL)
-		fileName = bb_xstrdup("/dev/root");
-	return fileName;
-}
-
+	closedir(dir);
 
-/* END CODE */
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
+	return retpath;
+}
diff --git a/libbb/loop.c b/libbb/loop.c
index c4c3da4b1..25f66fcea 100644
--- a/libbb/loop.c
+++ b/libbb/loop.c
@@ -19,10 +19,8 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
+
 #include <features.h>
-#if defined (__GLIBC__) && !defined(__UCLIBC__)
-#include <linux/posix_types.h>
-#endif
 #include <stdio.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -30,127 +28,108 @@
 #include <unistd.h>
 #include <sys/ioctl.h>
 #include "libbb.h"
-#ifdef CONFIG_FEATURE_MOUNT_LOOP
 
-/* Grumble...  The 2.6.x kernel breaks asm/posix_types.h
- * so we get to try and cope as best we can... */
+/* For 2.6, use the cleaned up header to get the 64 bit API. */
 #include <linux/version.h>
-
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
-#define __bb_kernel_dev_t   __kernel_old_dev_t
-#elif LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0)
-#define __bb_kernel_dev_t   __kernel_dev_t
-#else
-#define __bb_kernel_dev_t   unsigned short
-#endif
+#include <linux/loop.h>
+typedef struct loop_info64 bb_loop_info;
+#define BB_LOOP_SET_STATUS LOOP_SET_STATUS64
+#define BB_LOOP_GET_STATUS LOOP_GET_STATUS64
 
-/* Stuff stolen from linux/loop.h */
+/* For 2.4 and earlier, use the 32 bit API (and don't trust the headers) */
+#else
+/* Stuff stolen from linux/loop.h for 2.4 and earlier kernels*/
+#include <linux/posix_types.h>
 #define LO_NAME_SIZE        64
 #define LO_KEY_SIZE         32
 #define LOOP_SET_FD         0x4C00
 #define LOOP_CLR_FD         0x4C01
-#define LOOP_SET_STATUS     0x4C02
-#define LOOP_GET_STATUS     0x4C03
-struct loop_info {
+#define BB_LOOP_SET_STATUS  0x4C02
+#define BB_LOOP_GET_STATUS  0x4C03
+typedef struct {
 	int                lo_number;
-	__bb_kernel_dev_t  lo_device;
+	__kernel_dev_t     lo_device;
 	unsigned long      lo_inode;
-	__bb_kernel_dev_t  lo_rdevice;
+	__kernel_dev_t     lo_rdevice;
 	int                lo_offset;
 	int                lo_encrypt_type;
 	int                lo_encrypt_key_size;
 	int                lo_flags;
-	char               lo_name[LO_NAME_SIZE];
+	char               lo_file_name[LO_NAME_SIZE];
 	unsigned char      lo_encrypt_key[LO_KEY_SIZE];
 	unsigned long      lo_init[2];
 	char               reserved[4];
-};
+} bb_loop_info;
+#endif
 
 extern int del_loop(const char *device)
 {
-	int fd;
+	int fd,rc=0;
 
-	if ((fd = open(device, O_RDONLY)) < 0) {
-		bb_perror_msg("%s", device);
-		return (FALSE);
-	}
-	if (ioctl(fd, LOOP_CLR_FD, 0) < 0) {
+	if ((fd = open(device, O_RDONLY)) < 0) rc=1;
+	else {
+		if (ioctl(fd, LOOP_CLR_FD, 0) < 0) rc=1;
 		close(fd);
-		bb_perror_msg("ioctl: LOOP_CLR_FD");
-		return (FALSE);
 	}
-	close(fd);
-	return (TRUE);
+	return rc;
 }
 
-extern int set_loop(const char *device, const char *file, int offset,
-					int *loopro)
-{
-	struct loop_info loopinfo;
-	int fd, ffd, mode;
-
-	mode = *loopro ? O_RDONLY : O_RDWR;
-	if ((ffd = open(file, mode)) < 0 && !*loopro
-		&& (errno != EROFS || (ffd = open(file, mode = O_RDONLY)) < 0)) {
-		bb_perror_msg("%s", file);
-		return 1;
-	}
-	if ((fd = open(device, mode)) < 0) {
-		close(ffd);
-		bb_perror_msg("%s", device);
-		return 1;
-	}
-	*loopro = (mode == O_RDONLY);
-
-	memset(&loopinfo, 0, sizeof(loopinfo));
-	safe_strncpy(loopinfo.lo_name, file, LO_NAME_SIZE);
-
-	loopinfo.lo_offset = offset;
-
-	loopinfo.lo_encrypt_key_size = 0;
-	if (ioctl(fd, LOOP_SET_FD, ffd) < 0) {
-		bb_perror_msg("ioctl: LOOP_SET_FD");
-		close(fd);
-		close(ffd);
-		return 1;
-	}
-	if (ioctl(fd, LOOP_SET_STATUS, &loopinfo) < 0) {
-		(void) ioctl(fd, LOOP_CLR_FD, 0);
-		bb_perror_msg("ioctl: LOOP_SET_STATUS");
-		close(fd);
-		close(ffd);
-		return 1;
-	}
-	close(fd);
-	close(ffd);
-	return 0;
-}
-
-extern char *find_unused_loop_device(void)
+// Returns 0 if mounted RW, 1 if mounted read-only, <0 for error.
+// *device is loop device to use, or if *device==NULL finds a loop device to
+// mount it on and sets *device to a strdup of that loop device name.  This
+// search will re-use an existing loop device already bound to that
+// file/offset if it finds one.
+extern int set_loop(char **device, const char *file, int offset)
 {
 	char dev[20];
-	int i, fd;
+	bb_loop_info loopinfo;
 	struct stat statbuf;
-	struct loop_info loopinfo;
+	int i, dfd, ffd, mode, rc=1;
 
-	for (i = 0; i <= CONFIG_FEATURE_MOUNT_LOOP_MAX; i++) {
-		sprintf(dev, LOOP_FORMAT, i);
-		if (stat(dev, &statbuf) == 0 && S_ISBLK(statbuf.st_mode)) {
-			if ((fd = open(dev, O_RDONLY)) >= 0) {
-				if (ioctl(fd, LOOP_GET_STATUS, &loopinfo) != 0) {
-					if (errno == ENXIO) {	/* probably free */
-						close(fd);
-						return strdup(dev);
-					}
-				}
-				close(fd);
-			}
+	// Open the file.  Barf if this doesn't work.
+	if((ffd = open(file, mode=O_RDWR))<0)
+		if(errno!=EROFS || (ffd=open(file,mode=O_RDONLY))<0)
+			return errno;
+
+	// Find a loop device
+	for(i=0;rc;i++) {
+		sprintf(dev, LOOP_FORMAT, i++);
+		// Ran out of block devices, return failure.
+		if(stat(*device ? : dev, &statbuf) || !S_ISBLK(statbuf.st_mode)) {
+			rc=ENOENT;
+			break;
 		}
+		// Open the sucker and check its loopiness.
+		if((dfd=open(dev, mode))<0 && errno==EROFS)
+			dfd=open(dev,mode=O_RDONLY);
+		if(dfd<0) continue;
+
+		rc=ioctl(dfd, BB_LOOP_GET_STATUS, &loopinfo);
+		// If device free, claim it.
+		if(rc && errno==ENXIO) {
+			memset(&loopinfo, 0, sizeof(loopinfo));
+			safe_strncpy(loopinfo.lo_file_name, file, LO_NAME_SIZE);
+			loopinfo.lo_offset = offset;
+			// Associate free loop device with file
+			if(!ioctl(dfd, LOOP_SET_FD, ffd) &&
+			   !ioctl(dfd, BB_LOOP_SET_STATUS, &loopinfo)) rc=0;
+			else ioctl(dfd, LOOP_CLR_FD, 0);
+		// If this block device already set up right, re-use it.
+		// (Yes this is racy, but associating two loop devices with the same
+		// file isn't pretty either.  In general, mounting the same file twice
+		// without using losetup manually is problematic.)
+		} else if(strcmp(file,loopinfo.lo_file_name)
+					|| offset!=loopinfo.lo_offset) rc=1;
+		close(dfd);
+		if(*device) break;
 	}
-	return NULL;
+	close(ffd);
+	if(!rc) {
+		if(!*device) *device=strdup(dev);
+		return mode==O_RDONLY ? 1 : 0;
+	} else return rc;
 }
-#endif
-
 
 /* END CODE */
 /*
diff --git a/libbb/mtab.c b/libbb/mtab.c
index b1f74c476..fa4958c26 100644
--- a/libbb/mtab.c
+++ b/libbb/mtab.c
@@ -28,8 +28,8 @@
 #include "libbb.h"
 
 #define MTAB_MAX_ENTRIES 40
-static const int MS_RDONLY = 1;	/* Mount read-only.  */
 
+#ifdef CONFIG_FEATURE_MTAB_SUPPORT
 void erase_mtab(const char *name)
 {
 	struct mntent entries[MTAB_MAX_ENTRIES];
@@ -72,45 +72,4 @@ void erase_mtab(const char *name)
 	} else if (errno != EROFS)
 		bb_perror_msg(bb_path_mtab_file);
 }
-
-void write_mtab(char *blockDevice, char *directory,
-				char *filesystemType, long flags, char *string_flags)
-{
-	FILE *mountTable = setmntent(bb_path_mtab_file, "a+");
-	struct mntent m;
-
-	if (mountTable == 0) {
-		bb_perror_msg(bb_path_mtab_file);
-		return;
-	}
-	if (mountTable) {
-		int length = strlen(directory);
-
-		if (length > 1 && directory[length - 1] == '/')
-			directory[length - 1] = '\0';
-
-		if (filesystemType == 0) {
-			struct mntent *p = find_mount_point(blockDevice, "/proc/mounts");
-
-			if (p && p->mnt_type)
-				filesystemType = p->mnt_type;
-		}
-		m.mnt_fsname = blockDevice;
-		m.mnt_dir = directory;
-		m.mnt_type = filesystemType ? filesystemType : "default";
-
-		if (*string_flags) {
-			m.mnt_opts = string_flags;
-		} else {
-			if ((flags | MS_RDONLY) == flags)
-				m.mnt_opts = "ro";
-			else
-				m.mnt_opts = "rw";
-		}
-
-		m.mnt_freq = 0;
-		m.mnt_passno = 0;
-		addmntent(mountTable, &m);
-		endmntent(mountTable);
-	}
-}
+#endif
diff --git a/miscutils/eject.c b/miscutils/eject.c
index 8864687e4..3f1d6ab44 100644
--- a/miscutils/eject.c
+++ b/miscutils/eject.c
@@ -48,13 +48,9 @@ extern int eject_main(int argc, char **argv)
 	if((m = find_mount_point(device, bb_path_mtab_file))) {
 		if(umount(m->mnt_dir))
 			bb_error_msg_and_die("Can't umount");
-#ifdef CONFIG_FEATURE_MTAB_SUPPORT
-		else
-			erase_mtab(m->mnt_fsname);	
-#endif
+		else if(ENABLE_FEATURE_MTAB_SUPPORT) erase_mtab(m->mnt_fsname);	
 	}
-	if (ioctl(bb_xopen( device, 
-	                   (O_RDONLY | O_NONBLOCK)), 
+	if (ioctl(bb_xopen( device, (O_RDONLY | O_NONBLOCK)), 
 	          ( flags ? CDROMCLOSETRAY : CDROMEJECT)))
 	{
 		bb_perror_msg_and_die(device);
diff --git a/util-linux/Config.in b/util-linux/Config.in
index 7007915ba..7fde01971 100644
--- a/util-linux/Config.in
+++ b/util-linux/Config.in
@@ -323,54 +323,43 @@ config CONFIG_UMOUNT
 	  the tool to use.  If you enabled the 'mount' utility, you almost certainly
 	  also want to enable 'umount'.
 
-config CONFIG_FEATURE_MOUNT_FORCE
-	bool "  Support forced filesystem unmounting"
-	default n
-	depends on CONFIG_UMOUNT
-	help
-	  This allows you to _force_ a filesystem to be umounted.  This is generally
-	  only useful when you want to get rid of an unreachable NFS system.
-
 comment "Common options for mount/umount"
 	depends on CONFIG_MOUNT || CONFIG_UMOUNT
 
 config CONFIG_FEATURE_MOUNT_LOOP
-	bool "  Support for loop devices"
+	bool "  Support loopback mounts"
 	default n
 	depends on CONFIG_MOUNT || CONFIG_UMOUNT
 	help
-	  Enabling this feature allows automatic loopback mounts, meaning you can mount
-	  filesystems contained in normal files as well as in block devices.  The mount
-	  and umount commands will detect you are trying to mount a file instead of a
-	  block device, and transparently associate it with a loopback device (and free
-	  the loopback device on unmount) for you.
+	  Enabling this feature allows automatic mounting of files (containing
+	  filesystem images) via the linux kernel's loopback devices.  The mount
+	  command will detect you are trying to mount a file instead of a block
+	  device, and transparently associate the file with a loopback device.
+	  The umount command will also free that loopback device.
 	  
-	  You can still use the 'losetup' utility and mount the loopback device yourself
-	  if you need to do something advanced, such as specify an offset or cryptographic
-	  options to the loopback device.
-
-config CONFIG_FEATURE_MOUNT_LOOP_MAX
-	int "    max number of loop devices"
-	default 7
-	depends on CONFIG_FEATURE_MOUNT_LOOP
-	help
-	  This option sets the highest numbered loop device to be used
-	  automatically by the '-o loop' feature of mount.
+	  You can still use the 'losetup' utility (to manually associate files
+          with loop devices) if you need to do something advanced, such as
+	  specify an offset or cryptographic options to the loopback device.
+	  (If you don't want umount to free the loop device, use "umount -D".)
 
 config CONFIG_FEATURE_MTAB_SUPPORT
-	bool "  Support for a /etc/mtab file (instead of symlink to /proc/mounts)"
+	bool "  Support for the old /etc/mtab file"
 	default n
 	depends on CONFIG_MOUNT || CONFIG_UMOUNT
 	help
-	  If your root filesystem is writable and you wish to have the 'mount'
-	  utility create an mtab file listing the filesystems which have been
-	  mounted then you should enable this option.  Most people that use
-	  BusyBox have a read-only root filesystem, so they will leave this
-	  option disabled and BusyBox will use the /proc/mounts file.
-
-	  Note that even non-embedded developers probably want to have /etc/mtab
-	  be a symlink to /proc/mounts, since otherwise mtab can get out of sync
-	  with the real kernel mount state in numerous ways.
+	  Historically, Unix systems kept track of the currently mounted
+	  partitions in the file "/etc/mtab".  These days, the kernel exports
+	  the list of currently mounted partitions in "/proc/mounts", rendering
+	  the old mtab file obsolete.  (In modern systems, /etc/mtab should be
+	  a symlink to /proc/mounts.)
+
+	  The only reason to have mount maintain an /etc/mtab file itself is if
+	  your stripped-down embedded system does not have a /proc directory.
+	  If you must use this, keep in mind it's inherently brittle (for
+	  example a mount under chroot won't update it), can't handle modern
+	  features like separate per-process filesystem namespaces, requires
+	  that your /etc directory be writeable, tends to get easily confused
+	  by --bind or --move mounts, and so on.  (In brief: avoid.)
 
 config CONFIG_READPROFILE
 	bool "readprofile"
diff --git a/util-linux/losetup.c b/util-linux/losetup.c
index c94456522..11bd66ebf 100644
--- a/util-linux/losetup.c
+++ b/util-linux/losetup.c
@@ -27,33 +27,27 @@
 int
 losetup_main (int argc, char **argv)
 {
-  int delete = 0;
   int offset = 0;
-  int opt;
 
-  while ((opt = getopt (argc, argv, "do:")) != -1)
-    switch (opt)
-      {
-      case 'd':
-	delete = 1;
-	break;
-
-      case 'o':
-	offset = bb_xparse_number (optarg, NULL);
-	break;
-
-      default:
-	bb_show_usage();
-      }
-
-  if ((delete && (offset || optind + 1 != argc))
-      || (!delete && optind + 2 != argc))
-    bb_show_usage();
-
-  opt = 0;
-  if (delete)
-    return del_loop (argv[optind]) ? EXIT_SUCCESS : EXIT_FAILURE;
-  else
-    return set_loop (argv[optind], argv[optind + 1], offset, &opt)
-      ? EXIT_FAILURE : EXIT_SUCCESS;
+  /* This will need a "while(getopt()!=-1)" loop when we can have more than
+     one option, but for now we can't. */
+  switch(getopt(argc,argv, "do:")) {
+    case 'd':
+      /* detach takes exactly one argument */
+      if(optind+1==argc)
+        return del_loop(argv[optind]) ? EXIT_SUCCESS : EXIT_FAILURE;
+      break;
+
+    case 'o':
+      offset = bb_xparse_number (optarg, NULL);
+      /* Fall through to do the losetup */
+    case -1:
+      /* losetup takes two argument:, loop_device and file */
+      if(optind+2==argc)
+        return set_loop(&argv[optind], argv[optind + 1], offset)<0
+	    ? EXIT_FAILURE : EXIT_SUCCESS;
+      break;
+  }
+  bb_show_usage();
+  return EXIT_FAILURE;
 }
diff --git a/util-linux/mount.c b/util-linux/mount.c
index b059d7094..924d79d69 100644
--- a/util-linux/mount.c
+++ b/util-linux/mount.c
@@ -4,6 +4,7 @@
  *
  * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ * Copyright (C) 2005 by Rob Landley <rob@landley.net>
  *
  * 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
@@ -19,29 +20,6 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  *
- * 3/21/1999	Charles P. Wright <cpwright@cpwright.com>
- *		searches through fstab when -a is passed
- *		will try mounting stuff with all fses when passed -t auto
- *
- * 1999-04-17	Dave Cinege...Rewrote -t auto. Fixed ro mtab.
- *
- * 1999-10-07	Erik Andersen <andersen@codepoet.org>.
- *              Rewrite of a lot of code. Removed mtab usage (I plan on
- *              putting it back as a compile-time option some time),
- *              major adjustments to option parsing, and some serious
- *              dieting all around.
- *
- * 1999-11-06	mtab support is back - andersee
- *
- * 2000-01-12   Ben Collins <bcollins@debian.org>, Borrowed utils-linux's
- *              mount to add loop support.
- *
- * 2000-04-30	Dave Cinege <dcinege@psychosis.com>
- *		Rewrote fstab while loop and lower mount section. Can now do
- *		single mounts from fstab. Can override fstab options for single
- *		mount. Common mount_one call for single mounts and 'all'. Fixed
- *		mtab updating and stale entries. Removed 'remount' default.
- *
  */
 
 #include <limits.h>
@@ -52,351 +30,131 @@
 #include <stdio.h>
 #include <mntent.h>
 #include <ctype.h>
+#include <sys/mount.h>
+#include <fcntl.h>		// for CONFIG_FEATURE_MOUNT_LOOP
+#include <sys/ioctl.h>  // for CONFIG_FEATURE_MOUNT_LOOP
 #include "busybox.h"
 
-#ifdef CONFIG_NFSMOUNT
-#if defined(__UCLIBC__) && ! defined(__UCLIBC_HAS_RPC__)
+/* This is just a warning of a common mistake.  Possibly this should be a
+ * uclibc faq entry rather than in busybox... */
+#if ENABLE_NFSMOUNT && defined(__UCLIBC__) && ! defined(__UCLIBC_HAS_RPC__)
 #error "You need to build uClibc with UCLIBC_HAS_RPC for busybox mount with NFS support to compile."
 #endif
-#endif
-
-enum {
-	MS_MGC_VAL = 0xc0ed0000,	/* Magic number indicatng "new" flags */
-	MS_RDONLY = 1,		/* Mount read-only */
-	MS_NOSUID = 2,		/* Ignore suid and sgid bits */
-	MS_NODEV = 4,		/* Disallow access to device special files */
-	MS_NOEXEC = 8,		/* Disallow program execution */
-	MS_SYNCHRONOUS = 16,	/* Writes are synced at once */
-	MS_REMOUNT = 32,	/* Alter flags of a mounted FS */
-	MS_MANDLOCK = 64,	/* Allow mandatory locks on an FS */
-	S_QUOTA = 128,		/* Quota initialized for file/directory/symlink */
-	S_APPEND = 256,		/* Append-only file */
-	S_IMMUTABLE = 512,	/* Immutable file */
-	MS_NOATIME = 1024,	/* Do not update access times. */
-	MS_NODIRATIME = 2048,	/* Do not update directory access times */
-	MS_BIND = 4096,		/* Use the new linux 2.4.x "mount --bind" feature */
-	MS_MOVE = 8192,		/* Use the new linux 2.4.x "mount --move" feature */
-};
-
 
-#if defined CONFIG_FEATURE_MOUNT_LOOP
-#include <fcntl.h>
-#include <sys/ioctl.h>
-static int use_loop = FALSE;
+// These two aren't always defined in old headers
+#ifndef MS_BIND
+#define MS_BIND		4096
+#endif
+#ifndef MS_MOVE
+#define MS_MOVE		8192
 #endif
 
-extern int mount(__const char *__special_file, __const char *__dir,
-				 __const char *__fstype, unsigned long int __rwflag,
-				 __const void *__data);
-extern int umount(__const char *__special_file);
-extern int umount2(__const char *__special_file, int __flags);
-
-extern int sysfs(int option, unsigned int fs_index, char *buf);
+/* Consume standard mount options (from -o options or --options).
+ * Set appropriate flags and collect unrecognized ones as a comma separated
+ * string to pass to kernel */ 
 
-struct mount_options {
+struct {
 	const char *name;
-	unsigned long and;
-	unsigned long or;
+	long flags;
+} static const  mount_options[] = {
+	{"loop", 0},
+	{"defaults", 0},
+	{"noauto", 0},
+	{"ro", MS_RDONLY},
+	{"rw", ~MS_RDONLY},
+	{"nosuid", MS_NOSUID},
+	{"suid", ~MS_NOSUID},
+	{"dev", ~MS_NODEV},
+	{"nodev", MS_NODEV},
+	{"exec", ~MS_NOEXEC},
+	{"noexec", MS_NOEXEC},
+	{"sync", MS_SYNCHRONOUS},
+	{"async", ~MS_SYNCHRONOUS},
+	{"remount", MS_REMOUNT},
+	{"atime", MS_NOATIME},
+	{"noatime", MS_NOATIME},
+	{"diratime", MS_NODIRATIME},
+	{"nodiratime", MS_NODIRATIME},
+	{"bind", MS_BIND},
+	{"move", MS_MOVE}
 };
 
-static const struct mount_options mount_options[] = {
-	{"async", ~MS_SYNCHRONOUS, 0},
-	{"atime", ~0, ~MS_NOATIME},
-	{"defaults", ~0, 0},
-	{"noauto", ~0, 0},
-	{"dev", ~MS_NODEV, 0},
-	{"diratime", ~0, ~MS_NODIRATIME},
-	{"exec", ~MS_NOEXEC, 0},
-	{"noatime", ~0, MS_NOATIME},
-	{"nodev", ~0, MS_NODEV},
-	{"nodiratime", ~0, MS_NODIRATIME},
-	{"noexec", ~0, MS_NOEXEC},
-	{"nosuid", ~0, MS_NOSUID},
-	{"remount", ~0, MS_REMOUNT},
-	{"ro", ~0, MS_RDONLY},
-	{"rw", ~MS_RDONLY, 0},
-	{"suid", ~MS_NOSUID, 0},
-	{"sync", ~0, MS_SYNCHRONOUS},
-	{"bind", ~0, MS_BIND},
-	{"move", ~0, MS_MOVE},
-	{0, 0, 0}
-};
-
-static int
-do_mount(char *specialfile, char *dir, char *filesystemtype, long flags,
-		 void *string_flags, int useMtab, int fakeIt, char *mtab_opts,
-		 int mount_all)
-{
-	int status = 0;
-
-#if defined CONFIG_FEATURE_MOUNT_LOOP
-	char *lofile = NULL;
-#endif
-
-	if (!fakeIt) {
-#if defined CONFIG_FEATURE_MOUNT_LOOP
-		if (use_loop == TRUE) {
-			int loro = flags & MS_RDONLY;
-
-			lofile = specialfile;
-
-			specialfile = find_unused_loop_device();
-			if (specialfile == NULL) {
-				bb_error_msg_and_die("Could not find a spare loop device");
-			}
-			if (set_loop(specialfile, lofile, 0, &loro)) {
-				bb_error_msg_and_die("Could not setup loop device");
-			}
-			if (!(flags & MS_RDONLY) && loro) {	/* loop is ro, but wanted rw */
-				bb_error_msg("WARNING: loop device is read-only");
-				flags |= MS_RDONLY;
-			}
-		}
-#endif
-		status = mount(specialfile, dir, filesystemtype, flags, string_flags);
-		if (status < 0 && errno == EROFS) {
-			bb_error_msg("%s is write-protected, mounting read-only",
-					  specialfile);
-			status = mount(specialfile, dir, filesystemtype, flags |=
-						   MS_RDONLY, string_flags);
-		}
-		/* Don't whine about already mounted filesystems when mounting all. */
-		if (status < 0 && errno == EBUSY && mount_all) {
-			return TRUE;
-		}
-	}
-
-
-	/* If the mount was sucessful, do anything needed, then return TRUE */
-	if (status == 0 || fakeIt == TRUE) {
-
-#if defined CONFIG_FEATURE_MTAB_SUPPORT
-		if (useMtab) {
-			erase_mtab(specialfile);	/* Clean any stale entries */
-			write_mtab(specialfile, dir, filesystemtype, flags, mtab_opts);
-		}
-#endif
-		return (TRUE);
-	}
-
-	/* Bummer.  mount failed.  Clean up */
-#if defined CONFIG_FEATURE_MOUNT_LOOP
-	if (lofile != NULL) {
-		del_loop(specialfile);
-	}
-#endif
-
-	if (errno == EPERM) {
-		bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
-	}
-
-	return (FALSE);
-}
-
-
-static void paste_str(char **s1, const char *s2)
-{
-	*s1 = xrealloc(*s1, strlen(*s1) + strlen(s2) + 1);
-	strcat(*s1, s2);
-}
-
-/* Seperate standard mount options from the nonstandard string options */
+/* Uses the mount_options list above */
 static void parse_mount_options(char *options, int *flags, char **strflags)
 {
-	while (options) {
-		int gotone = FALSE;
+	// Loop through options
+	for(;;) {
+		int i;
 		char *comma = strchr(options, ',');
-		const struct mount_options *f = mount_options;
 
-		if (comma) {
-			*comma = '\0';
-		}
-
-		while (f->name != 0) {
-			if (strcasecmp(f->name, options) == 0) {
+		if(comma) *comma = 0;
 
-				*flags &= f->and;
-				*flags |= f->or;
-				gotone = TRUE;
+		// Find this option in mount_options
+		for(i = 0; i < (sizeof(mount_options) / sizeof(*mount_options)); i++) {
+			if(!strcasecmp(mount_options[i].name, options)) {
+				long fl = mount_options[i].flags;
+				if(fl < 0) *flags &= fl;
+				else *flags |= fl;
 				break;
 			}
-			f++;
-		}
-#if defined CONFIG_FEATURE_MOUNT_LOOP
-		if (!strcasecmp("loop", options)) {	/* loop device support */
-			use_loop = TRUE;
-			gotone = TRUE;
 		}
-#endif
-		if (!gotone) {
-			if (**strflags) {
-				/* have previous parsed options */
-				paste_str(strflags, ",");
-			}
-			paste_str(strflags, options);
+		// Unrecognized mount option?
+		if(i == sizeof(mount_options)) {
+			// Add it to strflags, to pass on to kernel
+			i = *strflags ? strlen(*strflags) : 0;
+			*strflags = xrealloc(*strflags, i+strlen(options)+2);
+			// Comma separated if it's not the first one
+			if(i) (*strflags)[i] = ',';
+			strcpy((*strflags)+i, options);
 		}
-		if (comma) {
+		// Advance to next option, or finish
+		if(comma) {
 			*comma = ',';
 			options = ++comma;
-		} else {
-			break;
-		}
+		} else break;
 	}
 }
 
-static int mount_one(char *blockDevice, char *directory, char *filesystemType,
-					 unsigned long flags, char *string_flags, int useMtab,
-					 int fakeIt, char *mtab_opts, int whineOnErrors,
-					 int mount_all)
-{
-	int status = 0;
-	if (strcmp(filesystemType, "auto") == 0) {
-		char buf[255];
-		FILE *f;
-		int read_proc = 0;
-
-		f = fopen("/etc/filesystems", "r");
-
-		if (f) {
-			while (fgets(buf, sizeof(buf), f)) {
-				if (*buf == '*') {
-					read_proc = 1;
-				} else if (*buf == '#') {
-					continue;
-				} else {
-					filesystemType = buf;
-
-					/* Add NULL termination to each line */
-					while (*filesystemType && !isspace(*filesystemType)) {
-						filesystemType++;
-					}
-					*filesystemType = '\0';
-
-					filesystemType = buf;
-
-					if (bb_strlen(filesystemType)) {
-						status = do_mount(blockDevice, directory, filesystemType,
-									 flags | MS_MGC_VAL, string_flags,
-									 useMtab, fakeIt, mtab_opts, mount_all);
-						if (status) {
-							break;
-						}
-					}
-
-				}
-			}
-			fclose(f);
-		} else {
-			read_proc = 1;
-		}
-
-		if (read_proc && !status) {
-
-			f = bb_xfopen("/proc/filesystems", "r");
+/* This does the work */
 
-			while (fgets(buf, sizeof(buf), f) != NULL) {
-				filesystemType = buf;
-				if (*filesystemType == '\t') {	/* Not a nodev filesystem */
-
-					/* Add NULL termination to each line */
-					while (*filesystemType && *filesystemType != '\n') {
-						filesystemType++;
-					}
-					*filesystemType = '\0';
-
-					filesystemType = buf;
-					filesystemType++;	/* hop past tab */
-
-					status = do_mount(blockDevice, directory, filesystemType,
-								 flags | MS_MGC_VAL, string_flags, useMtab,
-								 fakeIt, mtab_opts, mount_all);
-					if (status) {
-						break;
-					}
-				}
-			}
-			fclose(f);
-		}
-	} else {
-		status = do_mount(blockDevice, directory, filesystemType,
-					 flags | MS_MGC_VAL, string_flags, useMtab, fakeIt,
-					 mtab_opts, mount_all);
-	}
-
-	if (!status) {
-		if (whineOnErrors) {
-			bb_perror_msg("Mounting %s on %s failed", blockDevice, directory);
-		}
-		return (FALSE);
-	}
-	return (TRUE);
-}
-
-static void show_mounts(char *onlytype)
+extern int mount_main(int argc, char **argv)
 {
-	FILE *mountTable = setmntent(bb_path_mtab_file, "r");
-
-	if (mountTable) {
-		struct mntent *m;
+	char *string_flags = 0, *fsType = 0, *blockDevice = 0, *directory = 0,
+		 *loopFile = 0, *buf = 0,
+		 *files[] = {"/etc/filesystems", "/proc/filesystems", 0};
+	int i, opt, all = FALSE, fakeIt = FALSE, allowWrite = FALSE,
+	   	rc = EXIT_FAILURE, useMtab = ENABLE_FEATURE_MTAB_SUPPORT;
+	int flags=0xc0ed0000;	// Needed for linux 2.2, ignored by 2.4 and 2.6.
+	FILE *file = 0,*f = 0;
+	char path[PATH_MAX*2];
+	struct mntent m;
+	struct stat statbuf;
 
-		while ((m = getmntent(mountTable)) != 0) {
-			char *blockDevice = m->mnt_fsname;
+	/* parse long options, like --bind and --move.  Note that -o option
+	 * and --option are synonymous.  Yes, this means --remount,rw works. */
 
-			if (strcmp(blockDevice, "rootfs") == 0) {
-				continue;
-			} else if (strcmp(blockDevice, "/dev/root") == 0) {
-				blockDevice = find_real_root_device_name();
-			}
-			if (!onlytype || (strcmp(m->mnt_type, onlytype) == 0)) {
-				printf("%s on %s type %s (%s)\n", blockDevice, m->mnt_dir,
-					   m->mnt_type, m->mnt_opts);
-			}
-#ifdef CONFIG_FEATURE_CLEAN_UP
-			if (blockDevice != m->mnt_fsname) {
-				free(blockDevice);
-			}
-#endif
-		}
-		endmntent(mountTable);
-	} else {
-		bb_perror_msg_and_die(bb_path_mtab_file);
+	for(i = opt = 0; i < argc; i++) {
+		if(argv[i][0] == '-' && argv[i][1] == '-')
+			parse_mount_options(argv[i]+2, &flags, &string_flags);
+		else argv[opt++] = argv[i];
 	}
-	exit(EXIT_SUCCESS);
-}
+	argc = opt;
 
-extern int mount_main(int argc, char **argv)
-{
-	struct stat statbuf;
-	char *string_flags = bb_xstrdup("");
-	char *extra_opts;
-	int flags = 0;
-	char *filesystemType = "auto";
-	int got_filesystemType = 0;
-	char *device = xmalloc(PATH_MAX);
-	char *directory = xmalloc(PATH_MAX);
-	struct mntent *m = NULL;
-	int all = FALSE;
-	int fakeIt = FALSE;
-	int useMtab = TRUE;
-	int rc = EXIT_FAILURE;
-	FILE *f = 0;
-	int opt;
-
-	/* Parse options */
-	while ((opt = getopt(argc, argv, "o:rt:wafnv")) > 0) {
+	// Parse remaining options
+
+	while((opt = getopt(argc, argv, "o:t:rwafnv")) > 0) {
 		switch (opt) {
 		case 'o':
 			parse_mount_options(optarg, &flags, &string_flags);
 			break;
+		case 't':
+			fsType = optarg;
+			break;
 		case 'r':
 			flags |= MS_RDONLY;
 			break;
-		case 't':
-			filesystemType = optarg;
-			got_filesystemType = 1;
-			break;
 		case 'w':
-			flags &= ~MS_RDONLY;
+			allowWrite=TRUE;
 			break;
 		case 'a':
 			all = TRUE;
@@ -405,93 +163,238 @@ extern int mount_main(int argc, char **argv)
 			fakeIt = TRUE;
 			break;
 		case 'n':
-#ifdef CONFIG_FEATURE_MTAB_SUPPORT
 			useMtab = FALSE;
-#endif
 			break;
 		case 'v':
-			break;		/* ignore -v */
+			break;		// ignore -v
+		default:
+			bb_show_usage();
 		}
 	}
 
-	if (!all && (optind == argc)) {
-		show_mounts(got_filesystemType ? filesystemType : NULL);
-	}
+	// If we have no arguments, show currently mounted filesystems
 
-	if (optind < argc) {
-		/* if device is a filename get its real path */
-		if (stat(argv[optind], &statbuf) == 0) {
-			char *tmp = bb_simplify_path(argv[optind]);
+	if(!all && (optind == argc)) {
+		FILE *mountTable = setmntent(bb_path_mtab_file, "r");
 
-			safe_strncpy(device, tmp, PATH_MAX);
-		} else {
-			safe_strncpy(device, argv[optind], PATH_MAX);
+		if(!mountTable) bb_perror_msg_and_die(bb_path_mtab_file);
+
+		while (getmntent_r(mountTable,&m,path,sizeof(path))) {
+			blockDevice = m.mnt_fsname;
+
+			// Clean up display a little bit regarding root devie
+			if(!strcmp(blockDevice, "rootfs")) continue;
+			if(!strcmp(blockDevice, "/dev/root"))
+				blockDevice = find_block_device("/");
+
+			if(!fsType || !strcmp(m.mnt_type, fsType))
+				printf("%s on %s type %s (%s)\n", blockDevice, m.mnt_dir,
+					   m.mnt_type, m.mnt_opts);
+			if(ENABLE_FEATURE_CLEAN_UP && blockDevice != m.mnt_fsname)
+				free(blockDevice);
 		}
+		endmntent(mountTable);
+		return EXIT_SUCCESS;
 	}
 
-	if (optind + 1 < argc)
-		directory = bb_simplify_path(argv[optind + 1]);
+	/* The next argument is what to mount.  if there's an argument after that
+	 * it's where to mount it.  If we're not mounting all, and we have both
+	 * of these arguments, jump straight to the actual mount. */
+
+	statbuf.st_mode=0;
+	if(optind < argc)
+		blockDevice = !stat(argv[optind], &statbuf) ?
+		  	 	bb_simplify_path(argv[optind]) :
+				(ENABLE_FEATURE_CLEAN_UP ? strdup(argv[optind]) : argv[optind]);
+	if(optind+1 < argc) directory = bb_simplify_path(argv[optind+1]);
+
+    // If we don't have to loop through fstab, skip ahead a bit.
+
+	if(!all && optind+1!=argc) goto singlemount;
+
+	// Loop through /etc/fstab entries to look up this entry.
 
-	if (all || optind + 1 == argc) {
-		f = setmntent("/etc/fstab", "r");
+	if(!(file=setmntent("/etc/fstab","r")))
+		bb_perror_msg_and_die("\nCannot read /etc/fstab");
+	for(;;) {
 
-		if (f == NULL)
-			bb_perror_msg_and_die("\nCannot read /etc/fstab");
+		// Get next fstab entry
 
-		while ((m = getmntent(f)) != NULL) {
-			if (!all && (optind + 1 == argc)
-				&& ((strcmp(device, m->mnt_fsname) != 0)
-					&& (strcmp(device, m->mnt_dir) != 0))) {
+		if(!getmntent_r(file,&m,path,sizeof(path))) {
+			if(!all)
+				bb_perror_msg("Can't find %s in /etc/fstab\n", blockDevice);
+			break;
+		}
+		
+		// If we're mounting all and all doesn't mount this one, skip it.
+
+		if(all) {
+			if(strstr(m.mnt_opts,"noauto") || strstr(m.mnt_type,"swap"))
 				continue;
+			flags=0;
+
+		/* If we're mounting something specific and this isn't it, skip it.
+		 * Note we must match both the exact text in fstab (ala "proc") or
+		 * a full path from root */
+
+		} else if(strcmp(blockDevice,m.mnt_fsname) &&
+				  strcmp(argv[optind],m.mnt_fsname) &&
+				  strcmp(blockDevice,m.mnt_dir) &&
+				  strcmp(argv[optind],m.mnt_dir)) continue;
+
+		/* Parse flags from /etc/fstab (unless this is a single mount
+		 * overriding fstab -- note the "all" test above zeroed the flags,
+		 * to prevent flags from previous entries affecting this one, so
+		 * the only way we could get here with nonzero flags is a single
+		 * mount). */
+
+		if(!flags) {
+			if(ENABLE_FEATURE_CLEAN_UP) free(string_flags);
+			string_flags=NULL;
+			parse_mount_options(m.mnt_opts, &flags, &string_flags);
+		}
+
+		/* Fill out remaining fields with info from mtab */
+
+		if(ENABLE_FEATURE_CLEAN_UP) {
+			free(blockDevice);
+			blockDevice=strdup(m.mnt_fsname);
+			free(directory);
+			directory=strdup(m.mnt_type);
+		} else {
+			blockDevice=m.mnt_fsname;
+			directory=m.mnt_dir;
+		}
+		fsType=m.mnt_type;
+
+		/* Ok, we're ready to actually mount a specific source on a specific
+		 * directory now. */
+
+singlemount:
+
+		// If they said -w, override fstab
+
+		if(allowWrite) flags&=~MS_RDONLY;
+
+		// Might this be an NFS filesystem?
+
+		if(ENABLE_NFSMOUNT && (!fsType || !strcmp(fsType,"nfs")) &&
+			strchr(blockDevice, ':') != NULL)
+		{
+			if(nfsmount(blockDevice, directory, &flags, &string_flags, 1))
+				bb_perror_msg("nfsmount failed");
+			else {
+				rc=EXIT_SUCCESS;
+				fsType="nfs";
 			}
+		} else {
+			
+			// Do we need to allocate a loopback device?
 
-			if (all && (	/* If we're mounting 'all' */
-						   (strstr(m->mnt_opts, "noauto")) ||	/* and the file system isn't noauto, */
-						   (strstr(m->mnt_type, "swap")))) /* and isn't swap, then mount it */
+			if(ENABLE_FEATURE_MOUNT_LOOP && !fakeIt && S_ISREG(statbuf.st_mode))
 			{
-				continue;
+				loopFile = blockDevice;
+				blockDevice = 0;
+				switch(set_loop(&blockDevice, loopFile, 0)) {
+					case 0:
+					case 1:
+						break;
+					default:
+						bb_error_msg_and_die(
+							errno == EPERM || errno == EACCES ?
+							bb_msg_perm_denied_are_you_root :
+							"Couldn't setup loop device");
+						break;
+				}
 			}
 
-			if (all || flags == 0) {	/* Allow single mount to override fstab flags */
-				flags = 0;
-				string_flags[0] = 0;
-				parse_mount_options(m->mnt_opts, &flags, &string_flags);
-			}
+			/* If we know the fstype (or don't need to), jump straight
+			 * to the actual mount. */
 
-			strcpy(device, m->mnt_fsname);
-			strcpy(directory, m->mnt_dir);
-			filesystemType = bb_xstrdup(m->mnt_type);
-		  singlemount:
-			extra_opts = string_flags;
-			rc = EXIT_SUCCESS;
-#ifdef CONFIG_NFSMOUNT
-			if (strchr(device, ':') != NULL) {
-				filesystemType = "nfs";
-				if (nfsmount
-					(device, directory, &flags, &extra_opts, &string_flags,
-					 1)) {
-					bb_perror_msg("nfsmount failed");
-					rc = EXIT_FAILURE;
+			if(fsType || (flags & (MS_REMOUNT | MS_BIND | MS_MOVE)))
+				goto mount_it_now;
+		}
+		
+		// Loop through filesystem types until mount succeeds or we run out
+
+		for(i = 0; files[i] && rc; i++) {
+			f = fopen(files[i], "r");
+			if(!f) continue;
+			// Get next block device backed filesystem
+			for(buf = 0; (buf = fsType = bb_get_chomped_line_from_file(f));
+				   	free(buf))
+			{
+				// Skip funky entries in /proc
+				if(!strncmp(buf,"nodev",5) && isspace(buf[5])) continue;
+				
+				while(isspace(*fsType)) fsType++;
+				if(*buf=='#' || *buf=='*') continue;
+				if(!*fsType) continue;
+mount_it_now:
+				// Okay, try to mount
+
+				if (!fakeIt) {
+					for(;;) {
+						rc = mount(blockDevice, directory, fsType, flags, string_flags);
+						if(!rc || (flags&MS_RDONLY) || (errno!=EACCES && errno!=EROFS))
+							break;
+						bb_error_msg("%s is write-protected, mounting read-only", blockDevice);
+						flags|=MS_RDONLY;
+					}
 				}
+				if(!rc) break;
 			}
-#endif
-			if (!mount_one
-				(device, directory, filesystemType, flags, string_flags,
-				 useMtab, fakeIt, extra_opts, TRUE, all)) {
-				rc = EXIT_FAILURE;
+			if(f) fclose(f);
+			if(!f || !rc) break;
+		}
+
+		/* If the mount was sucessful, and we're maintaining an old-style
+		 * mtab file by hand, add new entry to it now. */
+		if((!rc || fakeIt) && useMtab) {
+			FILE *mountTable = setmntent(bb_path_mtab_file, "a+");
+
+			if(!mountTable) bb_perror_msg(bb_path_mtab_file);
+			else {
+				// Remove trailing / (if any) from directory we mounted on
+				int length=strlen(directory);
+				if(length>1 && directory[length-1] == '/')
+					directory[length-1]=0;
+
+				// Fill out structure (should be ok to re-use existing one).
+				m.mnt_fsname=blockDevice;
+				m.mnt_dir=directory;
+				m.mnt_type=fsType ? : "--bind";
+				m.mnt_opts=string_flags ? :
+					((flags & MS_RDONLY) ? "ro" : "rw");
+				m.mnt_freq = 0;
+				m.mnt_passno = 0;
+
+				// Write and close
+				addmntent(mountTable, &m);
+				endmntent(mountTable);
 			}
-			if (!all) {
-				break;
+		} else {
+			// Mount failed.  Clean up
+			if(loopFile) {
+				del_loop(blockDevice);
+				if(ENABLE_FEATURE_CLEAN_UP) free(loopFile);
 			}
+			// Don't whine about already mounted fs when mounting all.
+			if(rc<0 && errno == EBUSY && all) rc=0;
+			else if (errno == EPERM)
+				bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
 		}
-		if (f) {
-			endmntent(f);
+		// We couldn't free this earlier becase fsType could be in buf.
+		if(ENABLE_FEATURE_CLEAN_UP) {
+			free(buf);
+			free(blockDevice);
+			free(directory);
 		}
-		if (!all && f && m == NULL) {
-			fprintf(stderr, "Can't find %s in /etc/fstab\n", device);
-		}
-		return rc;
+		if(!all) break;
 	}
 
-	goto singlemount;
+	if(file) endmntent(file);
+	if(rc) bb_perror_msg("Mounting %s on %s failed", blockDevice, directory);
+
+	return rc ? : EXIT_FAILURE;
 }
diff --git a/util-linux/nfsmount.c b/util-linux/nfsmount.c
index 0ebab80f6..11ca3268e 100644
--- a/util-linux/nfsmount.c
+++ b/util-linux/nfsmount.c
@@ -303,7 +303,7 @@ return &p;
 }
 
 int nfsmount(const char *spec, const char *node, int *flags,
-	     char **extra_opts, char **mount_opts, int running_bg)
+	     char **mount_opts, int running_bg)
 {
 	static char *prev_bg_host;
 	char hostdir[1024];
@@ -399,7 +399,7 @@ int nfsmount(const char *spec, const char *node, int *flags,
 	/* add IP address to mtab options for use when unmounting */
 
 	s = inet_ntoa(server_addr.sin_addr);
-	old_opts = *extra_opts;
+	old_opts = *mount_opts;
 	if (!old_opts)
 		old_opts = "";
 	if (strlen(old_opts) + strlen(s) + 10 >= sizeof(new_opts)) {
@@ -408,7 +408,7 @@ int nfsmount(const char *spec, const char *node, int *flags,
 	}
 	sprintf(new_opts, "%s%saddr=%s",
 		old_opts, *old_opts ? "," : "", s);
-	*extra_opts = bb_xstrdup(new_opts);
+	*mount_opts = bb_xstrdup(new_opts);
 
 	/* Set default options.
 	 * rsize/wsize (and bsize, for ver >= 3) are left 0 in order to
diff --git a/util-linux/umount.c b/util-linux/umount.c
index 21c2e6e4d..6de71b4ab 100644
--- a/util-linux/umount.c
+++ b/util-linux/umount.c
@@ -3,20 +3,11 @@
  * Mini umount implementation for busybox
  *
  * 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
+ * Copyright (C) 2005 by Rob Landley <rob@landley.net>
+ * 
+ * This program is licensed under the GNU General Public license (GPL)
+ * version 2 or later, see http://www.fsf.org/licensing/licenses/gpl.html
+ * or the file "LICENSE" in the busybox source tarball for the full text.
  *
  */
 
@@ -26,273 +17,126 @@
 #include <errno.h>
 #include <string.h>
 #include <stdlib.h>
+#include <sys/mount.h>
 #include "busybox.h"
 
-/* Teach libc5 about realpath -- it includes it but the
- * prototype is missing... */
-#if (__GLIBC__ <= 2) && (__GLIBC_MINOR__ < 1)
-extern char *realpath(const char *path, char *resolved_path);
-#endif
-
-static const int MNT_FORCE = 1;
-static const int MS_MGC_VAL = 0xc0ed0000; /* Magic number indicatng "new" flags */
-static const int MS_REMOUNT = 32;	/* Alter flags of a mounted FS.  */
-static const int MS_RDONLY = 1;	/* Mount read-only.  */
-
-extern int mount (__const char *__special_file, __const char *__dir,
-			__const char *__fstype, unsigned long int __rwflag,
-			__const void *__data);
-extern int umount (__const char *__special_file);
-extern int umount2 (__const char *__special_file, int __flags);
-
-struct _mtab_entry_t {
-	char *device;
-	char *mountpt;
-	struct _mtab_entry_t *next;
-};
-
-static struct _mtab_entry_t *mtab_cache = NULL;
-
-
-
-#if defined CONFIG_FEATURE_MOUNT_FORCE
-static int doForce = FALSE;
-#endif
-#if defined CONFIG_FEATURE_MOUNT_LOOP
-static int freeLoop = TRUE;
-#endif
-#if defined CONFIG_FEATURE_MTAB_SUPPORT
-static int useMtab = TRUE;
-#endif
-static int umountAll = FALSE;
-static int doRemount = FALSE;
-
-
-
-/* These functions are here because the getmntent functions do not appear
- * to be re-entrant, which leads to all sorts of problems when we try to
- * use them recursively - randolph
- *
- * TODO: Perhaps switch to using Glibc's getmntent_r
- *        -Erik
- */
-static void mtab_read(void)
+extern int umount_main(int argc, char **argv)
 {
-	struct _mtab_entry_t *entry = NULL;
-	struct mntent *e;
+	int doForce = 0;
+	int freeLoop = ENABLE_FEATURE_MOUNT_LOOP;
+	int useMtab = ENABLE_FEATURE_MTAB_SUPPORT;
+	int umountAll = FALSE;
+	int doRemount = FALSE;
+	char path[2*PATH_MAX];
+	struct mntent me;
 	FILE *fp;
-
-	if (mtab_cache != NULL)
-		return;
-
-	if ((fp = setmntent(bb_path_mtab_file, "r")) == NULL) {
-		bb_error_msg("Cannot open %s", bb_path_mtab_file);
-		return;
-	}
-	while ((e = getmntent(fp))) {
-		entry = xmalloc(sizeof(struct _mtab_entry_t));
-		entry->device = strdup(e->mnt_fsname);
-		entry->mountpt = strdup(e->mnt_dir);
-		entry->next = mtab_cache;
-		mtab_cache = entry;
-	}
-	endmntent(fp);
-}
-
-static char *mtab_getinfo(const char *match, const char which)
-{
-	struct _mtab_entry_t *cur = mtab_cache;
-
-	while (cur) {
-		if (strcmp(cur->mountpt, match) == 0 ||
-			strcmp(cur->device, match) == 0) {
-			if (which == MTAB_GETMOUNTPT) {
-				return cur->mountpt;
-			} else {
-#if !defined CONFIG_FEATURE_MTAB_SUPPORT
-				if (strcmp(cur->device, "rootfs") == 0) {
-					continue;
-				} else if (strcmp(cur->device, "/dev/root") == 0) {
-					/* Adjusts device to be the real root device,
-					 * or leaves device alone if it can't find it */
-					cur->device = find_real_root_device_name();
-				}
-#endif
-				return cur->device;
-			}
+	int status=EXIT_SUCCESS;
+	struct mtab_list {
+		char *dir;
+		char *device;
+	   	struct mtab_list *next;
+	} *mtl, *m;
+
+	if(argc < 2) bb_show_usage();
+	
+	/* Parse any options */
+	while (--argc > 0 && **(++argv) == '-') {
+		while (*++(*argv)) {
+			if(**argv=='a') umountAll = TRUE;
+			else if(ENABLE_FEATURE_MOUNT_LOOP && **argv=='D') freeLoop = FALSE;
+			else if(ENABLE_FEATURE_MTAB_SUPPORT && **argv=='n') useMtab = FALSE;
+			else if(**argv=='f') doForce = 1;   // MNT_FORCE
+			else if(**argv=='l') doForce = 2;   // MNT_DETACH
+			else if(**argv=='r') doRemount = TRUE;
+			else if(**argv=='v');
+			else bb_show_usage();
 		}
-		cur = cur->next;
 	}
-	return NULL;
-}
-
-static char *mtab_next(void **iter)
-{
-	char *mp;
 
-	if (iter == NULL || *iter == NULL)
-		return NULL;
-	mp = ((struct _mtab_entry_t *) (*iter))->mountpt;
-	*iter = (void *) ((struct _mtab_entry_t *) (*iter))->next;
-	return mp;
-}
-
-static char *mtab_first(void **iter)
-{
-	struct _mtab_entry_t *mtab_iter;
-
-	if (!iter)
-		return NULL;
-	mtab_iter = mtab_cache;
-	*iter = (void *) mtab_iter;
-	return mtab_next(iter);
-}
-
-/* Don't bother to clean up, since exit() does that
- * automagically, so we can save a few bytes */
-#ifdef CONFIG_FEATURE_CLEAN_UP
-static void mtab_free(void)
-{
-	struct _mtab_entry_t *this, *next;
-
-	this = mtab_cache;
-	while (this) {
-		next = this->next;
-		free(this->device);
-		free(this->mountpt);
-		free(this);
-		this = next;
+	/* Get a list of mount points from mtab.  We read them all in now mostly
+	 * for umount -a (so we don't have to worry about the list changing while
+	 * we iterate over it, or about getting stuck in a loop on the same failing
+	 * entry.  Notice that this also naturally reverses the list so that -a
+	 * umounts the most recent entries first. */
+	
+	m=mtl=0;
+	if(!(fp = setmntent(bb_path_mtab_file, "r")))
+		bb_error_msg_and_die("Cannot open %s", bb_path_mtab_file);
+	while (getmntent_r(fp,&me,path,sizeof(path))) {
+		m=xmalloc(sizeof(struct mtab_list));
+		m->next=mtl;
+		m->device=bb_xstrdup(me.mnt_fsname);
+		m->dir=bb_xstrdup(me.mnt_dir);
+		mtl=m;
 	}
-}
-#endif
-
-static int do_umount(const char *name)
-{
-	int status;
-	char *blockDevice = mtab_getinfo(name, MTAB_GETDEVICE);
-
-	if (blockDevice && strcmp(blockDevice, name) == 0)
-		name = mtab_getinfo(blockDevice, MTAB_GETMOUNTPT);
-
-	status = umount(name);
+	endmntent(fp);
 
-#if defined CONFIG_FEATURE_MOUNT_LOOP
-	if (freeLoop && blockDevice != NULL && !strncmp("/dev/loop", blockDevice, 9))
-		/* this was a loop device, delete it */
-		del_loop(blockDevice);
-#endif
-#if defined CONFIG_FEATURE_MOUNT_FORCE
-	if (status != 0 && doForce) {
-		status = umount2(blockDevice, MNT_FORCE);
-		if (status != 0) {
-			bb_error_msg_and_die("forced umount of %s failed!", blockDevice);
-		}
-	}
-#endif
-	if (status != 0 && doRemount && errno == EBUSY) {
-		status = mount(blockDevice, name, NULL,
-					   MS_MGC_VAL | MS_REMOUNT | MS_RDONLY, NULL);
-		if (status == 0) {
-			bb_error_msg("%s busy - remounted read-only", blockDevice);
-		} else {
-			bb_error_msg("Cannot remount %s read-only", blockDevice);
+	/* If we're umounting all, then m points to the start of the list and
+	 * the argument list should be empty (which will match all). */
+	if(!umountAll) m=0;
+
+	// Loop through everything we're supposed to umount, and do so.
+	for(;;) {
+		int curstat;
+		
+		// Do we alrady know what to umount this time through the loop?
+		if(m) safe_strncpy(path,m->dir,PATH_MAX);
+		// For umountAll, end of mtab means time to exit.
+		else if(umountAll) break;
+		// Get next command line argument (and look it up in mtab list)
+		else if(!argc--) break;
+		else {
+			// Get next command line argument (and look it up in mtab list)
+			realpath(*argv++, path);
+			for(m = mtl; m; m = m->next)
+				if(!strcmp(path, m->dir) || !strcmp(path, m->device))
+					break;
 		}
-	}
-	if (status == 0) {
-#if defined CONFIG_FEATURE_MTAB_SUPPORT
-		if (useMtab)
-			erase_mtab(name);
-#endif
-		return (TRUE);
-	}
-	return (FALSE);
-}
 
-static int umount_all(void)
-{
-	int status = TRUE;
-	char *mountpt;
-	void *iter;
+		// Let's ask the thing nicely to unmount.
+		curstat = umount(path);
 
-	for (mountpt = mtab_first(&iter); mountpt; mountpt = mtab_next(&iter)) {
-		/* Never umount /proc on a umount -a */
-		if (strstr(mountpt, "proc")!= NULL)
-			continue;
-		if (!do_umount(mountpt)) {
-			/* Don't bother retrying the umount on busy devices */
-			if (errno == EBUSY) {
-				bb_perror_msg("%s", mountpt);
-				status = FALSE;
-				continue;
-			}
-			if (!do_umount(mountpt)) {
-				printf("Couldn't umount %s on %s: %s\n",
-					   mountpt, mtab_getinfo(mountpt, MTAB_GETDEVICE),
-					   strerror(errno));
-				status = FALSE;
-			}
+		// Force the unmount, if necessary.
+		if(curstat && doForce) {
+			curstat = umount2(path, doForce);
+			if(curstat)
+				bb_error_msg_and_die("forced umount of %s failed!", path);
 		}
-	}
-	return (status);
-}
 
-extern int umount_main(int argc, char **argv)
-{
-	char path[PATH_MAX], result = 0;
+		// If still can't umount, maybe remount read-only?	
+		if (curstat && doRemount && errno == EBUSY && m) {
+			curstat = mount(m->device, path, NULL, MS_REMOUNT|MS_RDONLY, NULL);
+			bb_error_msg(curstat ? "Cannot remount %s read-only" :
+						 "%s busy - remounted read-only", m->device);
+		}
 
-	if (argc < 2) {
-		bb_show_usage();
-	}
-#ifdef CONFIG_FEATURE_CLEAN_UP
-	atexit(mtab_free);
-#endif
+		/* De-allcate the loop device.  This ioctl should be ignored on any
+		 * non-loop block devices. */
+		if(ENABLE_FEATURE_MOUNT_LOOP && freeLoop && m)
+			del_loop(m->device);
 
-	/* Parse any options */
-	while (--argc > 0 && **(++argv) == '-') {
-		while (*++(*argv))
-			switch (**argv) {
-			case 'a':
-				umountAll = TRUE;
-				break;
-#if defined CONFIG_FEATURE_MOUNT_LOOP
-			case 'l':
-				freeLoop = FALSE;
-				break;
-#endif
-#ifdef CONFIG_FEATURE_MTAB_SUPPORT
-			case 'n':
-				useMtab = FALSE;
-				break;
-#endif
-#ifdef CONFIG_FEATURE_MOUNT_FORCE
-			case 'f':
-				doForce = TRUE;
-				break;
-#endif
-			case 'r':
-				doRemount = TRUE;
-				break;
-			case 'v':
-				break; /* ignore -v */
-			default:
-				bb_show_usage();
-			}
+		if(curstat) {
+			if(useMtab && m) erase_mtab(m->dir);
+			status = EXIT_FAILURE;
+			bb_perror_msg("Couldn't umount %s\n", path);
+		}
+		// Find next matching mtab entry for -a or umount /dev
+		while(m && (m = m->next)) 
+			if(umountAll || !strcmp(path,m->device))
+			   	break;
 	}
 
-	mtab_read();
-	if (umountAll) {
-		if (umount_all())
-			return EXIT_SUCCESS;
-		else
-			return EXIT_FAILURE;
+	// Free mtab list if necessary
+	
+	if(ENABLE_FEATURE_CLEAN_UP) {
+		while(mtl) {
+			m=mtl->next;
+			free(mtl->device);
+			free(mtl->dir);
+			free(mtl);
+			mtl=m;
+		}
 	}
 
-	do {
-		if (realpath(*argv, path) != NULL)
-			if (do_umount(path))
-				continue;
-		bb_perror_msg("%s", path);
-		result++;
-	} while (--argc > 0 && ++argv);
-	return result;
+	return status;
 }