#!/bin/sh
#
# Copyright (c) 2012-2015 Red Hat.
# Copyright (c) 2000-2008 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.
# 
# Start or Stop the Performance Co-Pilot pmlogger processes.
#
# The following is for chkconfig on RedHat based systems
# chkconfig: 2345 94 06
# description: pmlogger is a performance metrics logger 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:          pmlogger
# Required-Start:    $local_fs
# Should-Start:      $network $remote_fs $syslog $time $pmcd
# Required-Stop:     $local_fs
# Should-Stop:       $network $remote_fs $syslog $pmcd
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Control pmlogger (the performance metrics logger for PCP)
# Description:       Configure and control pmlogger (the performance metrics logger for the Performance Co-Pilot)
### END INIT INFO

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

PMLOGCTRL=$PCP_PMLOGGERCONTROL_PATH
PMLOGGER=$PCP_BINADM_DIR/pmlogger
rcprog=$PCP_DIR/etc/init.d/pmlogger
pmprog=$PCP_RC_DIR/pmlogger
prog=$PCP_RC_DIR/`basename $0`

tmp=`mktemp -d $PCP_DIR/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

case "$PCP_PLATFORM"
in
    mingw)
	# nothing we can usefully do here, skip the test
	#
	IAM=0
	;;

    *)
	# standard Unix/Linux style test
	#
	ID=id
	IAM=`$ID -u 2>/dev/null`
	if [ -z "$IAM" ]
	then
	    # do it the hardway
	    #
	    IAM=`$ID | sed -e 's/.*uid=//' -e 's/(.*//'`
	fi
	;;
esac

# 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.  Goal is
# to speed bootup by starting potentially slow (remote monitoring) pmlogger
# processes in the background.
#
_start_pmcheck()
{
    bgstatus=0
    bgtmp=`mktemp -d $PCP_DIR/var/tmp/pcp.XXXXXXXXX` || exit 1
    trap "rm -rf $bgtmp; exit \$bgstatus" 0 1 2 3 15

    pmlogger_check $VFLAG >$bgtmp/pmcheck.out 2>$bgtmp/pmcheck
    bgstatus=$?
    if [ -s $bgtmp/pmcheck ]
    then
	logfile="$PCP_LOG_DIR/pmlogger/pmlogger_check.log"
	mv -f $bgtmp/pmcheck $logfile

	message="pmlogger_check failed in $prog, see $logfile"
	$PCP_SYSLOG_PROG -p daemon.warning "$message"
	$PCP_BINADM_DIR/pmpost "$message"
    fi
    exit $bgstatus # co-process is now complete
}

_start_pmlogger()
{
    if which pmlogger_check >/dev/null 2>&1
    then
	# pmlogger_check uses $PMLOGCTRL to start everything that is needed
	#
	if [ ! -f $PMLOGCTRL ]
	then
	    echo "$prog:"'
Error: PCP archive logger control file '$PMLOGCTRL'
       is missing!  Cannot start any Performance Co-Pilot archive logger(s).'
	    # failure
	    false
	else
	    # Really start the pmlogger instances based on the control file.
	    # Done in the background to avoid delaying the init script,
	    # failure notification is external (syslog, log files).
	    #
	    $ECHO $PCP_ECHO_N "Starting pmlogger ..." "$PCP_ECHO_C"

	    # run as a co-process
	    _start_pmcheck &

	    # Container environment
	    if [ -n "$PCP_CONTAINER_IMAGE" ]
	    then
		# Set up the host crontab for pmlogger_{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-pmlogger-docker
		if [ ! -f $cronjob ]
		then
		    cp $PCP_VAR_DIR/config/pmlogger/crontab.docker $cronjob
		    $PCP_BINADM_DIR/pmpost "pmlogger script installed $cronjob"
		fi

		# In a container, pmlogger_check cannot run indefinitely -
		# if it did then the pmpause signal handler would reap the
		# pmlogger_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 "pmlogger_check" is missing) and the PCP archive logger(s)
	 cannot be started.'
	# failure
	false
    fi
    $RC_STATUS -v
}

_shutdown()
{
    # Is any pmlogger running?
    #
    _get_pids_by_name pmlogger >$tmp/tmp
    if [ ! -s $tmp/tmp ]
    then
 	[ "$1" = verbose ] && echo "$prog: pmlogger not running"
	rm -f $PCP_RUN_DIR/pmlogger.pid
	return 0
    fi

    [ "$1" = quietly ] || \
    $ECHO $PCP_ECHO_N "Stopping pmlogger ...""$PCP_ECHO_C"

    # Terminate those pmloggers started by either pmlogger_check or
    # pmlogger_daily ... relies on the -m option to pmlogger and the
    # annotation in the (optional) 4th line of the port map files
    #
    for pid in `cat $tmp/tmp`
    do
	if [ -f "$PCP_TMP_DIR/pmlogger/$pid" ]
	then
	    note=`sed -n -e 4p <"$PCP_TMP_DIR/pmlogger/$pid"`
	    if [ "$note" = pmlogger_check -o "$note" = pmlogger_daily ]
	    then
		pmsignal -s TERM $pid
	    fi
	fi
    done
    if [ "$1" = quietly ]
    then
	$RC_STATUS
    else
	true
	$RC_STATUS -v
    fi
    rm -f $PCP_RUN_DIR/pmlogger.pid
    $PCP_BINADM_DIR/pmpost "stop pmlogger from $prog"
}

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

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
    REBUILDOPT=''
    VFLAG='-V'
else				# For a quiet startup and shutdown
    ECHO=:
    REBUILDOPT=-s
    VFLAG=
fi

if [ "$IAM" != 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 the Performance Co-Pilot loggers.'
	exit
    fi
fi

# First reset status of this service
$RC_RESET
 
# Return values acc. to LSB for all commands but status:
# 0 - success
# 1 - misc error
# 2 - invalid or excess args
# 3 - unimplemented feature (e.g. reload)
# 4 - insufficient privilege
# 5 - program not installed
# 6 - program not configured
#
# Note that starting an already running service, stopping
# or restarting a not-running service as well as the restart
# with force-reload (in case signalling is not supported) are
# considered a success.
case "$1" in

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

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

	if [ -x $PMLOGGER ]
	then
	    # issue a warning if there's no chkconfig/crontab support
	    if is_chkconfig_on pmlogger
	    then
		:
	    elif [ "$0" = "$pmprog" -o "$0" = "$rcprog" ]
	    then
		echo "$prog: Warning: Performance Co-Pilot archive logger(s) not permanently enabled."
		chkconfig_on_msg pmlogger
	    fi

	    _start_pmlogger
	fi

	status=0
        ;;

  'stop')
	_shutdown verbose
	status=0
        ;;

  'status')
	# NOTE: $RC_CHECKPROC returns LSB compliant status values.
	$ECHO $PCP_ECHO_N "Checking for pmlogger:" "$PCP_ECHO_C"
        if [ -r /etc/rc.status ]
        then
            # SuSE
            $RC_CHECKPROC $PMLOGGER
            $RC_STATUS -v
            status=$?
        else
            # not SuSE
            $RC_CHECKPROC $PMLOGGER
            status=$?
            if [ $status -eq 0 ]
            then
                $ECHO running
            else
                $ECHO stopped
            fi
        fi
	;;

  *)
	[ -n "$PCP_CONTAINER_IMAGE" ] && exec "$@"
	_usage
        ;;
esac

