#! /bin/sh
#
# Init script for libvirtd
#
# (c) 2007 Guido Guenther <agx@sigxcpu.org>
# based on the skeletons that comes with dh_make
#
### BEGIN INIT INFO
# Provides:          libvirtd
# Required-Start:    $network $local_fs $remote_fs $syslog virtlogd
# Required-Stop:     $local_fs $remote_fs $syslog virtlogd
# Should-Start:      cgconfig
# Should-Stop:       cgconfig
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: libvirt management daemon
### END INIT INFO

PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
export PATH

NAME=libvirtd
DESC="libvirt management daemon"
DAEMON=/usr/sbin/$NAME
INITSCRIPT=/etc/init.d/$NAME
DEFAULTFILE=/etc/default/$NAME
PIDFILE=/var/run/$NAME.pid

start_libvirtd=yes
cgroups="cpuset cpu cpuacct devices freezer net_cls blkio perf_event"
! grep -qs cgroup_enable=memory /proc/cmdline || cgroups="$cgroups memory"

test -x $DAEMON || exit 0
. /lib/lsb/init-functions

DODTIME=1                   # Time to wait for the server to die, in seconds

# Include defaults if available
if [ -f $DEFAULTFILE ] ; then
    . $DEFAULTFILE
fi

check_start_libvirtd_option() {
    if [ ! "$start_libvirtd" = "yes" ]; then
        log_warning_msg "Not starting $DESC $NAME, disabled via $DEFAULTFILE"
        return 1
    else
        return 0
    fi
}

running_pid()
{
    # Check if a given process pid's cmdline matches a given name
    pid=$1
    name=$2
    [ -z "$pid" ] && return 1
    [ ! -d /proc/$pid ] && return 1
    cmd=`cat /proc/$pid/cmdline | tr "\000" "\n" | head -n 1 | cut -d : -f 1`
    # Is this the expected child?
    [ "$cmd" != "$name" ] && return 1
    return 0
}

running()
{
    # Check if the process is running looking at /proc
    # (works for all users)

    # No pidfile, probably no daemon present
    [ ! -f "$PIDFILE" ] && return 1
    # Obtain the pid and check it against the binary name
    pid=`cat $PIDFILE`
    running_pid $pid $DAEMON || return 1
    return 0
}

systemd_running()
{
    if [ -d /run/systemd/system ] ; then
        return 0
    fi
    return 1
}

mount_cgroups()
{
    if ! systemd_running
    then
        mount -t tmpfs cgroup_root /sys/fs/cgroup || return 1
        for M in $cgroups; do
            mkdir /sys/fs/cgroup/$M || return 1
            mount -t cgroup -o rw,nosuid,nodev,noexec,relatime,$M "cgroup_${M}" "/sys/fs/cgroup/${M}" || return 1
        done
    else
        log_warning_msg "Systemd running, skipping cgroup mount."
    fi
}

umount_cgroups()
{
    if ! systemd_running
    then
        for M in $cgroups; do
            umount "cgroup_${M}"
            rmdir /sys/fs/cgroup/$M
        done
        umount cgroup_root
    else
        log_warning_msg "Systemd running, skipping cgroup mount."
    fi
}

check_mount_cgroup_options() {
    if [ ! "$mount_cgroups" = "yes" ]; then
        return 1
    else
        return 0
    fi
}

force_stop() {
    # Forcefully kill the process
    [ ! -f "$PIDFILE" ] && return
    if running ; then
        kill -15 $pid
        # Is it really dead?
        [ -n "$DODTIME" ] && sleep "$DODTIME"s
        if running ; then
            kill -9 $pid
            [ -n "$DODTIME" ] && sleep "$DODTIME"s
            if running ; then
                echo "Cannot kill $LABEL (pid=$pid)!"
                exit 1
            fi
        fi
    fi
    rm -f $PIDFILE
    return 0
}

case "$1" in
    start)
        if ! check_start_libvirtd_option; then
            exit 0
        fi

        log_daemon_msg "Starting $DESC" "$NAME"
        if running ; then
            log_progress_msg "already running"
            log_end_msg 0
            exit 0
        fi
        rm -f $PIDFILE
        if check_mount_cgroup_options; then
            if ! mount_cgroups; then
                log_warning_msg "Can not mount cgroups layout"
                exit 1
            fi
        fi
        start-stop-daemon --start --quiet --pidfile $PIDFILE \
                          --exec $DAEMON -- -d $LIBVIRTD_ARGS
        if running; then
            log_end_msg 0
        else
            log_end_msg 1
        fi
        ;;
    stop)
        log_daemon_msg "Stopping $DESC" "$NAME"
        if ! running ; then
            log_progress_msg "not running"
            log_end_msg 0
            exit 0
        fi
        if check_mount_cgroup_options; then
            umount_cgroups
        fi
        start-stop-daemon --stop --quiet --pidfile $PIDFILE \
                          --exec $DAEMON
        log_end_msg 0
        ;;
    force-stop)
        log_daemon_msg "Forcefully stopping $DESC" "$NAME"
        force_stop
        if ! running; then
            log_end_msg 0
        else
            log_end_msg 1
        fi
        ;;
    restart)
        if ! check_start_libvirtd_option; then
            exit 0
        fi

        log_daemon_msg "Restarting $DESC" "$DAEMON"
        start-stop-daemon --oknodo --stop --quiet --pidfile $PIDFILE \
                          --exec $DAEMON
        [ -n "$DODTIME" ] && sleep $DODTIME
        start-stop-daemon --start --quiet --pidfile $PIDFILE \
                          --exec $DAEMON -- -d $LIBVIRTD_ARGS
        if running; then
            log_end_msg 0
        else
            log_end_msg 1
        fi
        ;;
    reload|force-reload)
        if running; then
            log_daemon_msg "Reloading configuration of $DESC" "$NAME"
            start-stop-daemon --stop --signal 1 --quiet --pidfile $PIDFILE \
                              --exec $DAEMON
            log_end_msg 0
        else
            log_warning_msg "$NAME not running, doing nothing."
        fi
        ;;
    status)
        log_daemon_msg "Checking status of $DESC" "$NAME"
        if running ; then
            log_progress_msg "running"
            log_end_msg 0
        else
            log_progress_msg "not running"
            log_end_msg 1
            if [ -f "$PIDFILE" ] ; then
                exit 1
            else
                exit 3
            fi
        fi
        ;;
    *)
        echo "Usage: $INITSCRIPT {start|stop|restart|reload|force-reload|status|force-stop}" >&2
        exit 1
        ;;
esac

exit 0
