#!/bin/bash

if [ "$1" == "unmount" ]
then
    MOUNT=`mount | grep '/mnt/data'`
    if [ -n "$MOUNT" ]
    then
        echo "Unmounting /mnt/data"
        umount /mnt/data
    else
        echo "ERROR: /mnt/data is not mounted."
    fi
else
    if [ -e /dev/sda4 ]
    then
      echo "Mounting /dev/sda4 as /mnt/data"
      mount /mnt/data
    else
      echo "ERROR: No HDD."
      exit 1
    fi
fi