launchctl-kick

#!/usr/bin/env bash
#
#  Synopsis:
#	Simple frontend for OSX launchctl to stop/unload/load/list services.
#  Usage:
#	sudo -i
#	launchctl-kick jmsdesk.blobio.*	
#
#	alias kickjms=launchctl-kick jmsdesk.blobio.*
#  Note:
#	Consider refactoring to call scripts launchctl-{load,unload}
#
#	is "stop" done by "unload"?
#
#	the action "kickstart" seems like what we should do instead of this
#	script.  however, "kickstart" requires a "service-target", which seems
#	to need meta info, like user or session 9acording to the manual). 
#	perhaps we can construct a "service-target" by querying the
#	*.plist file for, say, user id.  not sure.
#

LD=/Library/LaunchDaemons
LOAD_PAUSE_DURATION=3

log()
{
	echo "$@"
}

die()
{
	log "ERROR: $@" >&2
	exit 1
}

WARN()
{
	log "WARN (ok): $@" >&2
}

#
#  Extract a value from plist, cause the path syntax for extract lacks
#  documentation
#
get_plist_value()
{
        plutil -p $PLIST						|
		fgrep "\"$1\""						|
		awk '{print $3}'					|
		sed 's/"//g'
}

test $(pwd) = $LD && die "can not run in services dir: $D"
test $# = 1 || die "wrong argument count: got $#, expected 1"

cd $LD || die "cd $LD failed: exit status=$?"

for PLIST in $@;  do
	test -r $PLIST || die "can not read plist file: $PLIST"
	if [[ "$PLIST" =~ ^.*\.plist$ ]];  then
		SRV=$(basename $PLIST .plist)
	else
		die "service file must match *.plist: $PLIST"
	fi
	log "stopping $SRV"
	launchctl stop $SRV
	STATUS=$?
	case $STATUS in
	0)
		log "service stopped: $SRV"
		;;
	3)
		WARN 'process already stopped'
		;;
	*)
		EMSG=$(launchctl error $STATUS)
		die "launchctl stop failed: exit status: $EMSG"
		;;
	esac

	log "unloading plist: $PLIST"
	E=$(launchctl unload $PLIST 2>&1 | tail -1)
	STATUS=$?
	case $STATUS in
	0)
		#
		#  launchctl returns 0 when service already unloaded.
		#  also writes
		#
		#	Unload failed: 113: Could not find specified service
		#
		#  to standard error, so grep for that pattern.
		#
		#  the pain never ends.
		#
		if [[ "$(echo $E | tail -1)" =~ ^.*:[[:space:]]113:.*$ ]]; then
			WARN 'process not loaded'
		elif [ -n "$EMSG" ];  then
			die "launchctl: unexpected stderr: $EMSG"
		fi
		log "plist unloaded: $PLIST"
		;;
	*)
		EMSG=$(launchctl error $STATUS)
		die "launchctl stop failed: exit status: $EMSG"
		;;
	esac

	DISABLED=$(get_plist_value Disabled)
	if [ "$DISABLED" = 1 ];  then
		log "service disabled: $SRV"
		continue
	fi

	log "loading plist: $PLIST"
	launchctl load $PLIST
	STATUS=$?
	case $STATUS in
	0)
		;;
	*)
		EMSG=$(launchctl error $STATUS)
		die "launchctl load failed: exit status: $EMSG"
		;;
	esac
	log "service loaded: $SRV"
	log "sleep $LOAD_PAUSE_DURATION sec before kick start"
	sleep $LOAD_PAUSE_DURATION
	log "plist loaded: $PLIST"
	log "list service: $SRV"
	SRV_PID=$(
		launchctl list $SRV					|
		fgrep '"PID" = '					|
		awk '{print $3}'					|
		sed 's/[^0-9]//g'
	)
	if [ -n "$SRV_PID" ]; then
		log "pid of service process: $SRV_PID"
	else
		test -z "$SRV_PID" && WARN "can not get pid: $SRV"
		WARN "service failed to start: $SRV"
		STDERR=$(get_plist_value StandardErrorPath)
		if [ -n "$STDERR" ];  then
			log "stderr of service: $STDERR"
			cat <<END

$(basename $STDERR) ----------------------------------------------------------
END
			tput smso
			tail $STDERR
			tput rmso
			cat <<END
$(basename $STDERR) ----------------------------------------------------------

END
		else
			WARN "no key <StandardErrorPath>: $PLIST"
		fi

	fi
done