ClearGuests.sh

#!/bin/bash

# Resets a specified guest account, or all guest accounts, to the state of
# the "guest" user, to cleanup disk space and stale processes.
# Users who are logged in will not be cleaned up. Use the "-f" option to
# forcibly log them out first.

# abort on error
set -e

if [ "$1" = "-f" ]; then
    force=yes
fi

all_users=`getent passwd | sed -e 's/:.*//'`

for i in $all_users; do
    groups=`groups $i | sed -e 's/.* : //'`
    for g in $groups; do
        if [ "$g" = "students" ]; then
            guest_users="$guest_users $i"
            break
        fi
    done
done

do_users="$guest_users"

if [ -n "$1" ]; then
    do_users="$*"
fi

for i in $do_users; do
    for g in $guest_users; do
        if [ "$i" = "$g" ]; then
            is_guest=yes
            break
        fi
    done

    if [ -z "$is_guest" ]; then
        echo "$i is not a guest!"
        exit 2
    fi

    if who | grep -q "^$i "; then
        echo -n "$i is logged in! "
        if [ -n "$force" ]; then
            echo "killing session"
            gnome-session-save --force-logout $i
        else
            echo "skipping. Use -f to kill their session."
            continue
        fi
    fi

    echo

    if killall -0 -i $i; then
        echo -n "$i has processes running!"
        if [ -n "$force" ]; then
            echo "killing them"
            killall -9 -u $i
        else
            echo "skipping. Use -f to kill their processes."
            continue
        fi
    fi

    do_users_loggedout="$do_users_loggedout $i"
done

for i in $do_users_loggedout; do
    home=`getent passwd $i | cut -d: -f6`
    rsync -a --delete --exclude '/Documents' ~student-template/ $home
    if [ ! -d "$home/Documents" ]; then
        mkdir $home/Documents
    fi
    chown -R $i $home
done

exit 0