Restructure container manager startup script

Mount /cache and /data properly and stop bridge correctly.

scripts/container-manager.sh

@@ -21,6 +21,7 @@ if [ ! -e $SYSTEM_IMG ]; then
 	exit 1
 fi
 
+start() {
 	# Extract ramdisk content instead of trying to bind mount the
 	# cpio image file to allow modifications.
 	rm -Rf $RAMDISK_PATH
@@ -51,11 +52,28 @@ mkdir -p $SNAP_COMMON/lxc
 	# possible. See snapcraft.yaml for further details.
 	$SNAP/bin/anbox-bridge.sh start
 
-$SNAP/usr/sbin/aa-exec -p unconfined -- $SNAP/bin/anbox-wrapper.sh container-manager
+	exec $SNAP/usr/sbin/aa-exec -p unconfined -- $SNAP/bin/anbox-wrapper.sh container-manager
-pid=$!
+}
-waitpid $pid
+
+stop() {
+	for dir in cache data; do
+		umount $ROOTFS_PATH/$dir
+	done
+	umount $ROOTFS_PATH/system
+	umount $ROOTFS_PATH
 
 	$SNAP/bin/anbox-bridge.sh stop
+}
 
-umount $ROOTFS_PATH/system
+case "$1" in
-umount $ROOTFS_PATH/data
+	start)
+		start
+		;;
+	stop)
+		stop
+		;;
+	*)
+		echo "ERROR: Unknown command '$1'"
+		exit 1
+		;;
+esac

snapcraft.yaml

@@ -12,7 +12,8 @@ apps:
   anbox:
     command: bin/anbox-wrapper.sh
   container-manager:
-    command: bin/container-manager.sh
+    command: bin/container-manager.sh start
+    stop-command: bin/container-manager.sh stop
     daemon: simple
 # FIXME: a oneshot unit with start/stop commands needs also RemainAfterExit=yes
 # but this isn't supported by snapd yet. See LP #1647169 for details.