#!/bin/bash

# Copyright (C) 2009 Andy Spencer
# See ../COPYING for terms

# GLobals
TEST=false
RELOAD=false
FIFO=/lib/mkinit/cmd
INITCTL=/dev/initctl
PATH=/lib/mkinit/bin:/bin:/sbin:/usr/bin:/usr/sbin
export PATH

# Functions 
function usage {
	echo 'usage: '$0' [options] [command]'
	echo 
	echo 'Options:'
	echo '  -h,--help    Print usage information'
	echo '  -r,--relaod  Prevent spawning listeners when reloading'
	echo '  -t,--test    Fake all commands'
	echo
	echo 'Command:'
	echo '  boot         Execute boot-up procedures'
	echo '  halt         Execute shutdown procedures'
	echo '  reload       Re-execute init process'
	echo '  mk <rule>    Execute mk rule'
	echo '  start|stop|restart|zap|status <service>'
	echo '               Start,stop,restart,zap or query status of service'
	echo '  eval <cmd>   Execute command in mkinit process'
	exit
}

# Run mk on the init scripts
function runamk {
	$TEST && 
		export P=true
	/usr/lib/plan9/bin/mk \
		-f /etc/init.mk \
		-i -k "$@"
}

# Process one command
function process {
	cmd=$1
	shift
	arg=$*
	exec 1>/dev/console
	case "$cmd" in
	boot )
		echo
		echo mkinit -- booting
		runamk -a "$arg"
		;;
	restart )
		if [ "$arg" ]; then
			echo mkinit -- restarting $arg
			runamk "$arg"-stop
			runamk "$arg"-start
		fi
		;;
	start|stop|zap|status )
		if [ "$arg" ]; then
			echo mkinit -- ${cmd}ing $arg
			runamk "$arg-$cmd"
		fi
		;;
	mk|runlevel )
		if [ "$arg" ]; then
			[ "$cmd" = mk ] &&
				echo mkinit -- running mk cmd [$arg]
			[ "$cmd" = runlevel ] &&
				echo mkinit -- entering runlevel $arg
			runamk "$arg"
		fi
		;;
	reload )
		echo mkinit -- ${cmd}ing
		$TEST && 
			opt=-t
		exec $0 -r $opt
		;;
	eval )
		eval $arg
		;;
	?* )
		echo mkinit -- unknown command [$cmd] [$arg]
		;;
	esac
}

# Telinit
if [ $$ != 1 -a $1 != "-t" ]; then
	echo "$@" > $FIFO
	exit
fi

# Handle arguments
TMP=`getopt -n "$0" \
	--options     hrt \
	--longoptions help,reload,test \
	-- "$@"`
[ $? != 0 ] &&
	usage
eval set -- "$TMP"
while [ ! "$1" == "--" ]; do
	$TEST &&
		echo '$1=' $1
	case "$1" in
	-h|--help )
		usage
		;;
	-r|--reload )
		RELOAD=true
		;;
	-t|--test )
		TEST=true
		FIFO=/tmp/pipe
		INITCTL=/tmp/initctl
		trap "pkill -HUP -P $$" EXIT
		;;
	esac
	shift
done
shift; cmd=$1
shift; arg=$*

# Debugging output
if $TEST; then
	echo 'Options'
	echo '  test:' $TEST
	echo '  reload:' $RELOAD
	echo '  cmd:' $cmd
	echo '  arg:' $arg
fi

# Create fifos if they don't exist
test ! -e $FIFO &&
	mkfifo $FIFO
test ! -e $INITCTL &&
	mkfifo $INITCTL

# Initial boot-up
process $cmd $arg

# Fork listeners
if ! $RELOAD; then
	# Fork /dev/initctl listener
	( exec 0<&- 1<&- 2<&-
	initctld $INITCTL |
	while read line; do
		echo $line > $FIFO
	done ) &

	# Fork console listener
	# Readline uses stdin,stderr
	( exec 1<&-;
	while true; do
		while read -e -p "mkinit> " line; do
			echo $line > $FIFO
			history -s $line
		done
		$TEST && break
		exec 0</dev/console 2>/dev/console
		echo "Respawning on /dev/console.." >&2
		sleep 1
	done) <&0 &

	# Close stdin, stderr
	exec 0<&- 2<&-
fi

# Main loop
while true; do
	while read line; do
		process $line
	done < $FIFO
done