#!/bin/sh
#
# Copyright (c) 2012-2015 Red Hat.
# Copyright (c) 2000 Silicon Graphics, Inc.  All Rights Reserved.
# 
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation; either version 2 of the License, or (at your
# option) any later version.
# 
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
# for more details.
# 
# The following is for chkconfig on RedHat based systems
# chkconfig: 2345 94 06
# description: pmie is a performance inference engine for the Performance Co-Pilot (PCP)
#
# The following is for insserv(1) based systems,
# e.g. SuSE, where chkconfig is a perl script.
### BEGIN INIT INFO
# Provides:       pmie
# Required-Start: $remote_fs
# Should-Start: $local_fs $network $syslog $time $pmcd
# Required-Stop: $remote_fs
# Should-Stop:  $local_fs $network $syslog $pmcd
# Default-Start:  2 3 4 5
# Default-Stop:   0 1 6
# Short-Description: Control pmie (performance inference engine for PCP)
# Description:       Configure and control pmie (the performance inference engine for the Performance Co-Pilot)
### END INIT INFO

. $PCP_DIR/etc/pcp.env
. $PCP_SHARE_DIR/lib/rc-proc.sh

PMIECTRL=$PCP_PMIECONTROL_PATH
rcprog=$PCP_DIR/etc/init.d/pmie
pmprog=$PCP_RC_DIR/pmie
prog=$PCP_RC_DIR/`basename $0`

tmp=`mktemp -d /var/tmp/pcp.XXXXXXXXX` || exit 1
status=1
trap "rm -rf $tmp; exit \$status" 0 1 2 3 15

if [ $pmprog = $prog -o $rcprog = $prog ]
then
    VERBOSE_CTL=on
else
    VERBOSE_CTL=off
fi

id=`id | sed -e "s/(.*//" -e "s/.*=//"`
if [ "$id" != 0 -a "$1" != "status" ]
then
    if [ -n "$PCP_DIR" ]
    then
	: running in a non-default installation, do not need to be root
    else
	echo "$prog:"'
Error: You must be root (uid 0) to start or stop pmie.'
	exit
    fi
fi

_usage()
{
    echo "Usage: $pmprog [-v] {start|restart|condrestart|stop|status|reload|force-reload}"
}

_reboot_setup()
{
    # base directories and house-keeping for pmie instances
    #
    if [ ! -d "$PCP_TMP_DIR/pmie" ]
    then
	mkdir -p -m 0775 "$PCP_TMP_DIR/pmie"
	chown $PCP_USER:$PCP_GROUP "$PCP_TMP_DIR/pmie"
	if which restorecon >/dev/null 2>&1
	then
	    restorecon -r "$PCP_TMP_DIR"
	fi
    else
	rm -rf $tmp/ent $tmp/pid
	here=`pwd`
	cd "$PCP_TMP_DIR/pmie"
	_get_pids_by_name pmie | sort >$tmp/pid
	ls [0-9]* 2>&1 | sed -e '/\[0-9]\*/d' \
	    | sed -e 's/[ 	][ 	]*//g' | sort >$tmp/ent
	# remove entries without a pmie process
	rm -f `comm -23 $tmp/ent $tmp/pid`
	rm -f $tmp/ent $tmp/pid
	cd "$here"
    fi
}

# Note: _start_pmcheck() runs in the background, in parallel with the rest
# of the script (except in a container environment). It might complete well
# after the caller so tmpfile handling is especially problematic.  The goal
# is to speed bootup by starting potentially slow (remote monitoring) pmie
# processes in the background.
#
_start_pmcheck()
{
    bgstatus=0
    bgtmp=`mktemp -d /var/tmp/pcp.XXXXXXXXX` || exit 1
    trap "rm -rf $bgtmp; exit \$bgstatus" 0 1 2 3 15

    wait_option=''
    [ ! -z "$PMCD_WAIT_TIMEOUT" ] && wait_option="-t $PMCD_WAIT_TIMEOUT" 

    if pmcd_wait $wait_option
    then
	pmie_check >$bgtmp/pmie 2>&1
	bgstatus=$?
	if [ -s $bgtmp/pmie ]
	then
	    logfile=$PCP_LOG_DIR/pmie/pmie_check.log
	    mv -f $bgtmp/pmie $logfile

	    message="pmie_check start failed in $prog, see $logfile"
	    $PCP_SYSLOG_PROG -p daemon.warning "$message"
	    $PCP_BINADM_DIR/pmpost "$message"
	fi
    else
	bgstatus=$?
	message="pmcd_wait failed in $prog: exit status: $bgstatus" 
	$PCP_SYSLOG_PROG -p daemon.warning "$message"
	$PCP_BINADM_DIR/pmpost "$message"
    fi
    exit $bgstatus # co-process is now complete
}

_start_pmie()
{
    if which pmie_check >/dev/null 2>&1
    then
	# pmie_check uses $PMIECTRL to start everything that is needed
	if [ ! -f $PMIECTRL ]
	then
	    echo "$prog:"'
Error: PCP inference engine control file '$PMIECTRL'
       is missing!  Cannot start any Performance Co-Pilot inference engine(s).'
	    # failure
	    false
	else
	    $ECHO $PCP_ECHO_N "Starting pmie ..." "$PCP_ECHO_C"

	    # run as a co-process
	    _start_pmcheck &

	    # Container environment
	    if [ -n "$PCP_CONTAINER_IMAGE" ]
	    then
		# Set up the host crontab for pmie_{check,daily}.
		# This needs to be robust for when the container isn't running
		# so that a failing crontab entry doesn't spam the host logs.
		cronjob=/etc/cron.d/pcp-pmie-docker
		if [ ! -f $cronjob ]
		then
		    cp $PCP_VAR_DIR/config/pmie/crontab.docker $cronjob
		    $PCP_BINADM_DIR/pmpost "pmie script installed $cronjob"
		fi

		# In a container, pmie_check cannot run indefinitely -
		# if it did then the pmpause signal handler would reap the
		# pmie_check child and exit.
		wait

		# finally, stop here when running as a container
		exec $PCP_BINADM_DIR/pmpause
	    fi

            # success
            true
	fi
    else
        echo "$prog:"'
Warning: Performance Co-Pilot installation is incomplete (at least the
         script "pmie_check" is missing) and the PCP inference engine(s)
         cannot be started.'
        # failure
        false
    fi
    $RC_STATUS -v
}

_shutdown()
{
    _get_pids_by_name pmie >$tmp/pmies 2>&1
    if [ ! -s $tmp/pmies ]
    then
	[ "$1" = verbose ] && echo "$pmprog: pmie not running"
	return 0
    fi

    [ "$1" = quietly ] || \
    $ECHO $PCP_ECHO_N "Waiting for pmie process(es) to terminate ..." "$PCP_ECHO_C"

    pmie_check -s >$tmp/pmie 2>&1
    if [ -s $tmp/pmie ]
    then
	logfile=$PCP_LOG_DIR/pmie/pmie_check.log
	mv -f $tmp/pmie $logfile

	message="pmie_check stop failed in $prog, see $logfile"
	$PCP_SYSLOG_PROG -p daemon.warning "$message"
	$PCP_BINADM_DIR/pmpost "$message"
    fi

    if [ "$1" = quietly ]
    then
	$RC_STATUS
    else
	true
	$RC_STATUS -v
    fi
    rm -fr "$tmp/pmie" "$PCP_TMP_DIR"/pmie/*
    $PCP_BINADM_DIR/pmpost "stop pmie from $pmprog"
}

while getopts v c
do
    case $c
    in
	v)  # force verbose
	    VERBOSE_CTL=on
	    ;;
	*)
	    _usage
	    exit 1
	    ;;
    esac
done
shift `expr $OPTIND - 1`

if [ $VERBOSE_CTL = on ]
then                            # For a verbose startup and shutdown
    ECHO=$PCP_ECHO_PROG
else                            # For a quiet startup and shutdown
    ECHO=:
fi

case "$1" in
  'start'|'restart'|'condrestart'|'reload'|'force-reload')
	if [ "$1" = "condrestart" ] && ! is_chkconfig_on pmie
	then
	    status=0
	    exit
	fi

	_shutdown quietly

	# messages should go to stderr, not the GUI notifiers
	#
	unset PCP_STDERR

	_reboot_setup

	if which pmie >/dev/null 2>&1
	then
	    # issue a warning if there's no chkconfig/crontab support
	    if is_chkconfig_on pmie
	    then
		:
	    elif [ "$0" = "$pmprog" -o "$0" = "$rcprog" ]
	    then
		echo "$prog: Warning: Performance Co-Pilot Inference Engine (pmie) not permanently enabled."
		chkconfig_on_msg pmie
	    fi

	    _start_pmie
	fi
	status=0
        ;;

  'stop')
	_shutdown verbose
	status=0
        ;;

  'status')
        # NOTE: $RC_CHECKPROC returns LSB compliant status values.
	$ECHO $PCP_ECHO_N "Checking for pmie:" "$PCP_ECHO_C"
        if [ -r /etc/rc.status ]
        then
            # SuSE
            $RC_CHECKPROC pmie
            $RC_STATUS -v
            status=$?
        else
            # not SuSE
            $RC_CHECKPROC pmie
            status=$?
            if [ $status -eq 0 ]
            then
                $ECHO running
            else
                $ECHO stopped
            fi
        fi
        ;;
  *)
	[ -n "$PCP_CONTAINER_IMAGE" ] && exec "$@"
	_usage
        ;;
esac

