#!/bin/sh

### BEGIN INIT INFO
# Provides:          shinken
# Required-Start:    $local_fs
# Required-Stop:     $local_fs
# Default-Start:     2 3 4 5
# Default-Stop:      S 0 1 6
# Short-Description: Shinken monitoring daemon
# Description:       Shinken is a monitoring tool composed of many separated modules:
#     - arbiter     : the main one : control everything else.
#     - scheduler   : receives checks/actions from arbiter. Schedules & forwards them to pollers.
#     - poller      : receives the checks from a scheduler. Launch them and returns results
#     - broker      : manage results by looking at scheduler. Like export to flat file or db.
#     - reactionner : manage the failed checks by looking at scheduler. 
#     - receiver    : manage all passive data
### END INIT INFO


# http://refspecs.freestandards.org/LSB_3.1.1/LSB-Core-generic/LSB-Core-generic/iniscrptact.html


NAME="shinken"

AVAIL_MODULES="scheduler poller reactionner broker receiver arbiter"

## SHINKEN_MODULE_FILE is set by shinken-* if it's one of these that's calling us.
if [ -z "$SHINKEN_MODULE_FILE" ]; then
    SCRIPTNAME=$0
    _usage_mods_="[ <$AVAIL_MODULES> ]"
else
    SCRIPTNAME=$SHINKEN_MODULE_FILE
fi

curpath=$(cd $(dirname "$0") && pwd)
#echo curpath is $curpath filename is $(basename "$0")

## Default paths :
test "$BIN" || BIN=$(cd $curpath/.. && pwd)
test "$VAR" || VAR=$(cd $curpath/../../var && pwd)
test "$ETC" || ETC=$(cd $curpath/../../etc && pwd)

export PATH="${PATH:+$PATH:}/usr/sbin:/bin:/sbin"
export LANG=en_US.UTF8

# Uncomment the line below if you got the **lib** shinken installed
# on a non standard place (not in /usr/lib/python*)
#export PYTHONPATH="${PATH:+$PATH:}/opt/shinken"

# default
DEBUG=false
CMD=""
SUBMODULES=""

## This permits to overhidde the default "default shinken cfg file" : 
[ -z "$SHINKEN_DEFAULT_FILE" ] && SHINKEN_DEFAULT_FILE="/etc/default/$NAME" 
## so you can now do:
## bash -c "SHINKEN_DEFAULT_FILE=$your_own_default_file $init_path/shinken $action $args"
## to easily use your own config

#echo "Using $SHINKEN_DEFAULT_FILE .."

usage() {
    cat << END
Usage: $SCRIPTNAME [ -d ] {start|stop|restart|status|check} $_usage_mods_

 -d  start requested module(s) in debug mode, only useful with start|restart

END
}

if [ "$1" = "-d" ]; then
    DEBUG="1"
    shift
fi

if [ $# -eq 0 ]; then
    usage >&2
    exit 2
fi

CMD=$1
shift
SUBMODULES=$*

if [ -z "$SUBMODULES" ]; then
    SUBMODULES=$AVAIL_MODULES
else
    # check given modules
    for mod1 in $SUBMODULES; do
        found=0
        for mod2 in $AVAIL_MODULES; do
            [ $mod1 = $mod2 ] && found=1;
        done
        [ $found = 0 ] && { usage >&2 ; exit 2 ; }
    done
fi


# Reads configuration variable file if it is present
[ -r "$SHINKEN_DEFAULT_FILE" ] && . "$SHINKEN_DEFAULT_FILE"


# Now look if some required variables are pre defined :
if ! test "$SHINKENCFG"
then
    SHINKENCFG="$ETC/nagios.cfg"
fi
if ! test "$SHINKENSPECIFICCFG"
then
    SHINKENSPECIFICCFG="$ETC/shinken-specific.cfg"
fi


# Now place us in our var directory so even our arbiter will be
# happy for opening its pid and cmd files
cd $VAR

#echo BIN=$BIN
#echo VAR=$VAR
#echo ETC=$ETC

#set -xv

# 
echo_success() {
   log_end_msg 0 $*
}

echo_failure() {
    log_end_msg 1 $*
}

#log_end_msg


# Load the VERBOSE setting and other rcS variables
[ -f /etc/default/rcS ] && . /etc/default/rcS

# Source function library.
[ -f /etc/rc.d/init.d/functions ] && . /etc/rc.d/init.d/functions

[ -f /lib/lsb/init-functions ] && . /lib/lsb/init-functions



################################################

#
# returns the pid for a submodule
#

getpidfile() {
    mod="$1"
    modPIDVAR=$(echo $mod | tr 'a-z' 'A-Z')"PID"
    pidfile=$(echo $(eval echo \${$modPIDVAR}))
    if test "$pidfile"
    then
        echo "$pidfile"
    else
        echo "$VAR/${mod}d.pid"
    fi
}

getmodpid() {
    mod=$1
    pidfile=$(getpidfile "$mod")
    if [ -s $pidfile ]; then
        cat $pidfile
    fi
}


getdebugfile() {
    mod="$1"
    modDEBUG=$(echo $mod | tr 'a-z' 'A-Z')"DEBUGFILE"
    debugfile=$(echo $(eval echo \${$modDEBUG}))
    if test "$debugfile"
    then
        echo "$debugfile"
    else
        echo "${VAR}/${mod}-debug.log"
    fi
}

#
# Display status
#
do_status() {
    mod=$1
    pidfile=$(getpidfile "$mod")
    [ -e "$pidfile" ] || {
        echo "$mod NOT RUNNING (pidfile ($pidfile) not exist)"
        return 3
    }
    [ -r "$pidfile" ] || {
        echo "$mod NOT RUNNING (pidfile ($pidfile) unreadable)"
        return 3
    }
    pid=$(cat "$pidfile")
    if [ -z "$pid" ]; then
        echo "$mod NOT RUNNING (pid file empty)"
        return 4
    fi
    ps -p "$pid" >/dev/null 2>&1
    rc=$?
    if [ $rc != 0 ]; then
        log_failure_msg  "$mod NOT RUNNING (process $pid doesn't exist ?)"
        return 1
    fi
    echo "$mod RUNNING (pid $pid)"
    return 0
}

#
# starts our modules
#
do_start() {
    mod=$1
    modfilepath="$BIN/shinken-${mod}"
    [ -e "$modfilepath" ] || {
        log_failure_msg "FAILED: did not found $mod file ($modfilepath) ; are you sure shinken-$mod is installed ?"
        return 5
    }
    [ "$DEBUG" = 1 ] && DEBUGCMD="--debug "$(getdebugfile "$mod")
    if [ "$mod" != "arbiter" ]; then
        output=$("$modfilepath" -d -c "$ETC/${mod}d.ini" $DEBUGCMD 2>&1)
        rc=$?
    else
        output=$("$modfilepath" -d -c "$SHINKENCFG" -c "$SHINKENSPECIFICCFG" $DEBUGCMD 2>&1)
        rc=$?
    fi
    # debug:
    #resfile="/tmp/bad_start_for_$mod"
    #echo "$output" > "$resfile" || true
    if [ $rc != 0 ]; then
        resfile="/tmp/bad_start_for_$mod"
        echo "$output" > "$resfile" || true
        output=$(echo "$output" | tail -1)
        echo "FAILED: $output (full output is in $resfile)"
        return 1
    fi
    echo "OK"
    return 0
}

#
# stops modules
#
do_stop() {
    mod=$1
    pid=$(getmodpid "$mod")
    statusoutput=$(do_status "$mod")
    [ $? -ne 0 ] && {
        echo "$statusoutput"
        return 0
    }
    if [ ! -z "$pid" ]; then
        kill "$pid"
        sleep 0.5
        ## TODO: instead of 'sleep 1' : wait up to when pid file is removed (with timeout) ?
        for i in 1 2 3
        do
            # TODO : use a better way to get the children pids..
            allpids="$(ps -aef | grep "$pid" | grep "shinken-$mod" | awk '{print $2}')"
            if [ -z "$allpids" ]; then
                echo "OK"
                return 0
            fi
            sleep 1
        done
        echo "there are still remaining processes to $mod running.. ; trying to kill them (SIGTERM).."
        allpids="$(ps -aef | grep "$pid" | grep "shinken-$mod" | awk '{print $2}')"
        for cpid in $(ps -aef | grep "$pid" | grep "shinken-$mod" | awk '{print $2}'); do
            kill $cpid > /dev/null 2>&1
        done
        for i in 1 2 3
        do
            # TODO : eventually use a better way to get the children pids..
            allpids="$(ps -aef | grep "$pid" | grep "shinken-$mod" | awk '{print $2}')"
            if [ -z "$allpids" ]; then
                echo "OK"
            	return 0
            fi
            sleep 1
        done
        echo "there are still remaining processes to $mod running.. ; trying to kill -9 them.."
        allpids="$(ps -aef | grep "$pid" | grep "shinken-$mod" | awk '{print $2}')"
        for cpid in $(ps -aef | grep "$pid" | grep "shinken-$mod" | awk '{print $2}'); do
            kill -9 $cpid > /dev/null 2>&1
        done
        sleep 1
        allpids="$(ps -aef | grep "$pid" | grep "shinken-$mod" | awk '{print $2}')"
        if [ ! -z "$allpids" ]; then
            echo "FAILED: one or more process for $mod are still running after kill -9 !"
            echo "Remaining processes are (pids="$allpids"):"
            ps -lf $(for p in $allpids ; do echo -n "-p$p " ; done)
            echo "You should check this." 
            return 1
        fi
        echo "OK"
    else
        echo "NOT RUNNING"
    fi
    return 0
}

#
# does the config check
#
do_check() {
    [ "$DEBUG" = 1 ] && DEBUGCMD="--debug $VAR/${mod}-debug.log"
    "$BIN/shinken-arbiter" -v -c "$ETC/nagios.cfg" -c "$ETC/shinken-specific.cfg" $DEBUGCMD 2>&1
    return $?
}


############################

do_start_() {
    echo  "Starting $1: "
    status=$(do_status "$1")
    rc=$?
    if [ $rc -eq 0 ]; then
        log_warning_msg "Already running"
        return
    fi
    if test "$1" = "arbiter"
    then
        # arbiter is special : 
        # it doesn't actually declare a "workdir" properties in its config
        # so we have explicitely to cd to the "VAR" directory.
        # so that the default pidfile ( == nagios lock_file) which is now "arbiterd.pid"
        # will be created at the correct place.  
        cd "$VAR"
        # TODO: check if other possibility wouldn't be better:
        # declare a "workdir" properties for the arbiter module definition.. in shinken-specific.cfg.
        # but if the lock_file path is absolute then this 'cd' isn't required.
    fi
    startoutput=$(do_start "$1")
    rc=$?
    if [ $rc -eq 0 ]; then
        echo_success  
    else
        echo "$startoutput" 
        echo_failure
    fi
    return $rc
}

do_stop_() {
    echo  "Stopping $1"
    statusoutput=$(do_status "$1")
    rc=$?
    if [ $rc -ne 0 ]; then
        failuremsg="Couldn't get status of $1 : $statusoutput"
    else
        stopoutput=$(do_stop "$1" 2>&1)
        rc=$?
        [ $rc -ne 0 ] && failuremsg="Couldn't stop $1 : $stopoutput"
    fi
    if [ $rc -ne 0 ]; then
        log_failure_msg "$failuremsg"
        echo_failure
    else
        echo_success
    fi
    return $rc
}

do_restart_() {
    mod="$1"
    echo "Restarting $mod"
    if [ "$mod" = "arbiter" ]; then
        do_check_ "$mod"
        checkrc=$?
        if [ $checkrc -ne 0 ]; then
           return 1
        fi
    fi 
    stopoutput=$(do_stop "$mod")
    startoutput=$(do_start "$mod")
    rc=$?
    if [ $rc -eq 0 ]; then
        echo_success
    else
        log_failure_msg "$startoutput"
        echo_failure
    fi
    return $rc
}

do_status_() {
    mod=$1
    echo  "Checking status of $mod"
    do_status "$1"
    rc=$?
    if [ $rc -eq 0 ]; then
        echo_success
    else
        echo_failure
    fi

}

do_check_() {
    echo "Doing config check"
    output=$(do_check "$1" 2>&1)
    rc=$?
    if [ $rc -eq 0 ]; then
        echo_success
    else
        check_res_file="/tmp/shinken_checkconfig_result"
        echo "$output" > "$check_res_file"
        output=$(echo "$output" | tail -1)
        log_warning_msg "full result is in ${check_res_file}"
        log_failure_msg "ConfigCheck failed: $output"
        echo_failure
    fi
    return $rc
}
do_checkconfig_() { do_check_ "$1" ; }


############################

do_cmd_on() {
    action=$1
    mods=$2
    for mod in $mods
    do
        do_${action}_ "$mod"
    done
}


############################
## Main:

case "$CMD" in
    start|stop|restart|status)
        do_cmd_on "$CMD" "$SUBMODULES"
        ;;
    check|checkconfig)
        do_cmd_on "$CMD" "arbiter"
        ;;
    *)
        usage >&2
        exit 2
        ;;
esac

