#!/bin/bash

dev="$(findmnt -nfvo SOURCE -- "/")"

# If it's a partition, expand that first using growpart.
if [ "$(lsblk -ndo TYPE -- "$dev")" = part ]; then
	disk="$(lsblk -ndpo PKNAME -- "$dev")"
	partnum="${dev##*[!0-9]}"
	growpart "$disk" "$partnum" || { [ $? -ne 1 ] && exit 1; }
fi

# Inform kernel of new partition
partprobe

# Expand the filesystem.
resize2fs -- "$dev" || exit 1