#! /bin/sh

usage () {
	echo "Usage: $0 --type|--label|--uuid <device>"
}

case $1 in
	--type)
		vol_id_opt=--type
		blkid_tag=TYPE
		;;
	--label)
		vol_id_opt=--label
		blkid_tag=LABEL
		;;
	--uuid)
		vol_id_opt=--uuid
		blkid_tag=UUID
		;;
	*)
		usage >&2
		exit 1
		;;
esac
shift

if (export PATH="/lib/udev:$PATH"; type vol_id) >/dev/null 2>&1; then
	PATH="/lib/udev:$PATH" vol_id "$vol_id_opt" "$1"
elif type blkid >/dev/null 2>&1; then
	blkid -o value -s "$blkid_tag" "$1"
else
	exit 1
fi