#! /bin/sh
#
# umountfs	Turn off swap and unmount all local filesystems.
#

PATH=/sbin:/bin:/usr/sbin:/usr/bin

# Ensure /proc is mounted
test -r /proc/mounts || mount -t proc proc /proc

echo "Deactivating swap..."
swapoff -a

# We leave /proc mounted, the umount of /dev/devpts seems to fail
# quite frequently, the busybox umount apparently gives up at the
# first failure, so it is necessary to go file system by file
# system.  It is necessary to go backward in the /proc list, because
# later things may have been mounted on earlier mounts.
devfs=
unmount() {
	local dev mp type opts
	if read dev mp type opts
	then
		# recurse - unmount later items
		unmount
		# skip /proc and /dev but not the sub-directories
		case "$mp" in
		/|/proc)return 0;;
		/dev)	devfs=1
			return 0;;
		esac
		# then unmount this, if possible, otherwise make
		# it read-only
		umount -f -r "$mp"
	fi
}

echo "Unmounting local filesystems..."
unmount </proc/mounts

# now /dev and read-only /  (halt/reboot may need /proc!)
test -n "$devfs" && umount -f -r /dev
mount -o remount,ro /