terminal-screensaverd

#!/bin/bash

function conf() {
	# Improved function still relies on tilde expansion, but should be safe.
	# Feel free to create user accounts named '`rm -rf /`' if you like :)
	# This also only returns the first match in the file, rather than
	# potentially returning a confusing mess if multiple options match.
	# Exception handling is non-existant, but that's nothing new.
	# Thanks to cut's nature, matching lines containing no spaces
	# will be returned unaltered.
	if [ "x$2" = "x" ]; then
		homedir=~
	else
		eval homedir="$(printf "~%q" "$2")"
	fi
	[ -d "$homedir" ] || return 2 # user has a home directory?
	[ -e "$homedir/.terminal-screensaver.conf" ] || return 3 # that directory has a config file?
	[ -O "$homedir/.terminal-screensaver.conf" ] || return 4 # that config file is safe?
	grep -m 1 -e "^$1" -- "$homedir/.terminal-screensaver.conf" | cut -d' ' -f2-
}

PID_DIR=/var/run/terminal-screensaver
mkdir -p $PID_DIR
chmod a+w $PID_DIR

while :; do
	echo "screensaverd called"
	for pid in `ls $PID_DIR`; do
		echo "checking $pid"
		user=`ps -o user= $pid`
		idle="`conf 'idle-minutes-until-start' $user`"
		if test `find $PID_DIR/$pid -mmin +$idle`; then
			echo "too old"
			kill -SIGALRM $pid || rm $PID_DIR/$pid
		fi
	done
	sleep 15
done