integrate-distro.sh: Add support for /dev/loopXXX

Signed-off-by: Jan Lindemann <jan@janware.com>

scripts/integrate-distro.sh

@@ -473,7 +473,8 @@ get_opts()
 				shift
 				;;
 			-w)
-				cwd=$2
+				cwd="$2"
+				cd "$cwd"
 				shift
 				;;
 			-s)
@@ -499,6 +500,12 @@ log()
 	echo $@ >&2
 }
 
+fatal()
+{
+	log $@
+	exit 1
+}
+
 run()
 {
 	local exit_on_error=0
@@ -1297,8 +1304,13 @@ fi
 
 if [ "$install_dev" ]; then
 
+	tmp=`realpath "$install_dev"`
+	[ -b "$tmp" ] || fatal "device \"$install_dev\" is not a link to a block device"
+	install_dev="$tmp"
+
 	case $install_dev in
 	/dev/sd*) part_sep="";;
+	/dev/loop*) part_sep="";;
 	/dev/nbd*) part_sep="p";;
 	esac
 
@@ -1314,9 +1326,11 @@ if [ "$install_dev" ]; then
 	/dev/sde) install_grub_dev_num=4;;
 	/dev/nbd*)
 		install_grub_dev_num=${d/\/dev\/nbd/};;
+	/dev/loop*)
+		install_grub_dev_num=0;;
 	*)
-		log "device \"$install_dev\" can't be mapped onto a grub device number, edit $myname to add support"
+		fatal "device \"$install_dev\" can't be mapped onto a grub device number, edit $myname to add support"
-		exit 1;;
+		;;
 	esac
 
 	run_dev=/dev/sda