Allow disk resizing

BOOT="$IMG/boot.img"

[ ! -f "$BOOT" ] && echo "ERROR: Boot image does not exist ($BOOT)" && exit 81

DATA="${IMG}/data.img"

DISK_SIZE=$(echo "${DISK_SIZE}" | sed 's/MB/M/g;s/GB/G/g;s/TB/T/g')

DATA_SIZE=$(numfmt --from=iec "${DISK_SIZE}")

DATA="$IMG/data${DISK_SIZE}.img"

if [ -f "${DATA}" ]; then

if [ ! -f "$DATA" ]; then

  OLD_SIZE=$(stat -c%s "${DATA}")

  # Resize disk to new size if needed

  if [ "$DATA_SIZE" -ne "$OLD_SIZE" ]; then

    if [ "$DATA_SIZE" -gt "$OLD_SIZE" ]; then

      echo "Resizing data disk from $OLD_SIZE to $DATA_SIZE bytes.."

      fallocate -l "${DATA_SIZE}" "${DATA}"

    fi

    if [ "$DATA_SIZE" -lt "$OLD_SIZE" ]; then

      echo "INFO: Shrinking existing disks is not supported yet!"

      echo "INFO: Creating backup of old drive in storage folder..."

      mv -f "${DATA}" "${DATA}.bak"

    fi

  fi

fi

if [ ! -f "${DATA}" ]; then

  # Check free diskspace

  SPACE=$(df --output=avail -B 1 "$IMG" | tail -n 1)

  SPACE=$(df --output=avail -B 1 "${IMG}" | tail -n 1)

  if (( DATA_SIZE > SPACE )); then

    echo "ERROR: Not enough free space to create virtual disk." && exit 82

    echo "ERROR: Not enough free space to create virtual disk." && exit 84

  fi

  # Create an empty file

  if ! fallocate -l "${DATA_SIZE}" "${DATA}"; then

    rm -f "${DATA}"

    echo "ERROR: Could not allocate file for virtual disk." && exit 82

    echo "ERROR: Could not allocate file for virtual disk." && exit 85

  fi

  # Check if file exists

  if [ ! -f "${DATA}" ]; then

    echo "ERROR: Data image does not exist ($DATA)" && exit 86

  fi

[ ! -f "$DATA" ] && echo "ERROR: Data image does not exist ($DATA)" && exit 83

fi

KVM_DISK_OPTS="\

    -drive id=cdrom0,if=none,format=raw,readonly=on,file=${BOOT} \