USB automount

usb-automount.sh

#!/bin/bash

# This script is called from our systemd unit file to mount or unmount
# a USB drive.

usage()
{
    echo "Usage: $0 {add|remove} device_name (e.g. sdb1)"
    exit 1
}

if [[ $# -ne 2 ]]; then
    usage
fi

ACTION=$1
DEVBASE=$2
DEVICE="/dev/${DEVBASE}"

# See if this drive is already mounted, and if so where
MOUNT_POINT=$(/bin/mount | /bin/grep ${DEVICE} | /usr/bin/awk '{ print $3 }')

do_mount()
{
    if [[ -n ${MOUNT_POINT} ]]; then
        echo "Warning: ${DEVICE} is already mounted at ${MOUNT_POINT}"
        exit 1
    fi

    ## Get info for this drive: $ID_FS_LABEL, $ID_FS_UUID, and $ID_FS_TYPE
    #eval $(/sbin/blkid -o udev ${DEVICE})

    ## Figure out a mount point to use
    #LABEL=${ID_FS_UUID}
    #if /bin/grep -q " /media/${LABEL} " /etc/mtab; then
    #    # Already in use, make a unique one
    #    LABEL+="-${DEVBASE}"
    #fi
    #MOUNT_POINT="/media/${LABEL}"

    MOUNT_POINT="/media/usb"

    echo "Mount point: ${MOUNT_POINT}"

    #/bin/mkdir -p ${MOUNT_POINT}

    # Global mount options
    OPTS="ro,relatime"

    # File system type specific mount options
    if [[ ${ID_FS_TYPE} == "vfat" ]]; then
        OPTS+=",users,gid=100,umask=000,shortname=mixed,utf8=1,flush"
    fi

    if ! /bin/mount -o ${OPTS} ${DEVICE} ${MOUNT_POINT}; then
        echo "Error mounting ${DEVICE} (status = $?)"
        #/bin/rmdir ${MOUNT_POINT}
        exit 1
    fi

    echo "**** Mounted ${DEVICE} at ${MOUNT_POINT} ****"

    # Symlink to /media/usb
    #ln -sf ${MOUNT_POINT} /media/usb
}

do_unmount()
{
    if [[ -z ${MOUNT_POINT} ]]; then
        echo "Warning: ${DEVICE} is not mounted"
    else
        /bin/umount -l ${DEVICE}
        echo "**** Unmounted ${DEVICE}"
    fi

    # Delete all empty dirs in /media that aren't being used as mount
    # points. This is kind of overkill, but if the drive was unmounted
    # prior to removal we no longer know its mount point, and we don't
    # want to leave it orphaned...
    #for f in /media/* ; do
    #    if [[ -n $(/usr/bin/find "$f" -maxdepth 0 -type d -empty) ]]; then
    #        if ! /bin/grep -q " $f " /etc/mtab; then
    #            echo "**** Removing mount point $f"
    #            /bin/rmdir "$f"
    #        fi
    #    fi
    #done
}

case "${ACTION}" in
    add)
        do_mount
        ;;
    remove)
        do_unmount
        ;;
    *)
        usage
        ;;
esac

##
# SYSTEMD
##

# > /etc/systemd/system/usb-automount\@.service

[Unit]
Description=Mount USB Drive on %i

[Service]
Type=oneshot
RemainAfterExit=true
ExecStart=/kxkm/usb-automount.sh add %i
ExecStop=/kxkm/usb-automount.sh remove %i

##
# UDEV
##

> /etc/udev/rules.d/99-local.rules

KERNEL=="sd[a-z][0-9]", SUBSYSTEMS=="usb", ACTION=="add", RUN+="/bin/systemctl start usb-automount@%k.service"
KERNEL=="sd[a-z][0-9]", SUBSYSTEMS=="usb", ACTION=="remove", RUN+="/bin/systemctl stop usb-automount@%k.service"


## ORIGINAL
# https://serverfault.com/questions/766506/automount-usb-drives-with-systemd