Automatic USB drive mounting in WSL

mount_usb.sh

#!/bin/bash -e
# Small script to automatically mount/unmount USB drive in WSL

usage() {
  cat << EOF
usage: $(basename $0) [-h] [-l] [-u|-m]

Options: 
-h
  Show this message
-l
  List al USB drives with their DeviceID and their VolumeName
-u|-m 
  Mount (-m) or unmount (-u) all USB drives to /mnt/deviceid with the same DeviceID (e.g. E:\) as Windows.
EOF
}

mount_usb() {
  for ((i=1;i<${#DeviceID_list[@]};i++)); do
    DeviceID=${DeviceID_list[$i]/:};
    VolumeName=${VolumeName_list[$i]};
    echo "Mounting ${VolumeName} (${DeviceID}:\\) at /mnt/${DeviceID,,}"
    case ${DeviceID,,} in
      a|b|c|d|e|f|g|h|i|j|k|l|m|n|o|p|q|r|s|t|u|v|w|x|y|z)
          mkdir -p /mnt/${DeviceID,,}
          mount -t drvfs ${DeviceID,,}: /mnt/${DeviceID,,}
      ;;
      *)
      echo "error: cannot mount ${VolumeName}: DeviceID ${DeviceID,,} should be a letter from a to z" > /dev/stderr
      return 2
      ;;
    esac
  done
}

umount_usb() {
  for ((i=1;i<${#DeviceID_list[@]};i++)); do
    DeviceID=${DeviceID_list[$i]/:};
    VolumeName=${VolumeName_list[$i]};
    echo "Unmounting ${DeviceID}:\\${VolumeName} at /mnt/${DeviceID,,}"
    if [[ -d /mnt/${DeviceID,,} ]]; then
        umount /mnt/${DeviceID,,}
        rmdir /mnt/${DeviceID,,}
    else
      echo "error: cannot unmount ${VolumeName}: is not mounted at /mnt/${DeviceID,,}" > /dev/stderr
      return 3
    fi
  done
}


list_usb() {
  {
    echo "DeviceID VolumeName"
    for ((i=2;i<=${#DeviceID_list[@]};i++)); do
        DeviceID=${DeviceID_list[$i]};
        VolumeName=${VolumeName_list[$i]};
      echo ${DeviceID} ${VolumeName}
    done 
  } | column -t
}

# Global variable used everywhere
wmic="/mnt/c/Windows/System32/Wbem/wmic.exe"
DeviceID_list=( $( ${wmic} logicaldisk where drivetype=2 get DeviceID | tr '\r\n' ' ' ) )
VolumeName_list=( $( ${wmic} logicaldisk where drivetype=2 get VolumeName | tr '\r\n' ' ' ) )
 
while getopts huml arg; do
  case ${arg} in
    h)
      usage
      exit 1
      ;;
    u)
      umount_usb
      ;;
    m)
      mount_usb
      ;;
    l)
      list_usb
      ;;
    *) # By default mount everything
      mount_usb
      ;;
  esac
done

exit 0