#!/bin/bash
#
# Start/Stop the CGroups Rules Engine Daemon
#
# Copyright Red Hat Inc. 2008
#
# Authors:	Steve Olivieri <sjo@redhat.com>
# This program is free software; you can redistribute it and/or modify it
# under the terms of version 2.1 of the GNU Lesser General Public License
# as published by the Free Software Foundation.
# 
# This program is distributed in the hope that it would be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
#
# cgred		CGroups Rules Engine Daemon
# chkconfig:	- 14 86
# description:	This is a daemon for automatically classifying processes \
#		into cgroups based on UID/GID.
#

. /etc/init.d/smgl_init

### BEGIN INIT INFO
# Short-Description:	start and stop the cgroups rules engine daemon
# Description:		CGroup Rules Engine is a tool for automatically using \
#			cgroups to classify processes
# processname: cgrulesengd
# pidfile: /var/run/cgred.pid
# Provides:		cgrulesengd
DESC='CGroup Rules Engine is a tool for automatically using cgroups to classify processes'
RUNLEVEL=S
NEEDS="+local_fs +syslog cgconfig"
### END INIT INFO

# For convenience
processname=cgrulesengd
servicename=cgred
prefix=/usr;exec_prefix=${prefix};sbindir=${exec_prefix}/sbin
PROGRAM=$sbindir/cgrulesengd
CGRED_CONF=/etc/cgrules.conf
lockfile="/var/lock/${servicename}"
pidfile=/var/run/cgred.pid


# Sanity checks
[ -x $PROGRAM ] || exit 1

# Read in configuration options.
if [ -f "/etc/sysconfig/cgred" ] ; then
	. /etc/sysconfig/cgred
	OPTIONS="$NODAEMON $LOG"
	if [ -n "$LOG_FILE" ]; then
		OPTIONS="$OPTIONS --logfile=$LOG_FILE"
	fi
	if [ -n "$SOCKET_USER" ]; then
		OPTIONS="$OPTIONS -u $SOCKET_USER"
	fi
	if [ -n "$SOCKET_GROUP" ]; then
		OPTIONS="$OPTIONS -g $SOCKET_GROUP"
	fi
else
	OPTIONS=""
fi

start()
{
	echo -n $"Starting CGroup Rules Engine Daemon: "
	if [ -f "$lockfile" ] && pgrep "cgrulesengd" > /dev/null; then
		print_status failure "${servicename} is already running with PID `cat ${pidfile}`"
		return 0
	fi
	num=`grep "cgroup" /proc/mounts | awk '$3=="cgroup"' | wc -l`
	if [ $num -eq 0 ]; then
		echo
		if awk '$3 == "cgroup2" { found = 1 } END { exit !found }' /proc/mounts; then
			print_status failure $"cgrulesengd only understands cgroup v1, and this host runs the unified hierarchy"
			echo "$servicename: disable this service; cgconfig delegates a subtree"
			echo "$servicename: to each user instead of classifying processes here"
		else
			print_status failure $"Cannot find cgroups, is cgconfig service running?"
		fi
		return 1
	fi

	# cgrulesengd hears about new processes through the kernel's process
	# event connector, which registers /proc/net/connector when it is built
	# in. Without it the daemon starts and then stays permanently idle.
	if [ ! -e /proc/net/connector ]; then
		echo
		print_status failure $"kernel lacks CONFIG_CONNECTOR, cgrulesengd cannot see new processes"
		return 1
	fi
	loadproc ${PROGRAM} ${OPTIONS}

	touch "$lockfile"
	if [ $? -ne 0 ]; then
		return 1
	fi
	echo "`pidof $processname`" > $pidfile
	return 0
}

stop()
{
	echo -n $"Stopping CGroup Rules Engine Daemon..."
	if [ ! -f $pidfile ]; then
		print_status success
		return 0
	fi
	killproc "${PROGRAM}" 'SIGTERM' || return 1

	rm -f "$lockfile" "$pidfile"
	return 0
}

status()
{
  statusproc ${PROGRAM}
}

restart()
{
  #
  # If the "reload" option is implemented, move the "force-reload"
  # option to the "reload" entry above. If not, "force-reload" is
  # just the same as "restart".
  #
  echo "Restarting $DESC: $servicename"
  stop
  sleep 1
  start
}


.