wrtpresence

#/bin/sh
#trap "" SIGHUP
# 
# Info:			Service Wrapper for main service script.
# Usage:		This script gets called during embedded linux startup.
# 
#
# Diagnostics, Maintenance, Installation, Prerequisites:
# 	See main service script.
#
# Variables:
#
SERVICE_MAIN_SRC="/root/wrtpresence_main.sh"
SERVICE_MAIN_TMP="/tmp/wrtpresence_main.sh"
# 
SERVICE_MAIN_LOG="/tmp/wrtpresence.log"
SERVICE_PID_FILE="/tmp/wrtpresence_main.sh.pid"
SERVICE_EVENT_FIFO="/tmp/wrtpresence_main.sh.event_fifo"
SHELL_INTERPRETER="bash"
#
# ========================================
# ======== FUNCTTION BLOCK START =========
# ========================================
createInstance ()
{
	#
	# Usage: createInstance
	#
	# Check prerequisites.
	#
	if [ ! -f "${SERVICE_MAIN_SRC}" ]; then
		echo "$0: Creating service instance FAILED. Install ${SERVICE_MAIN_SRC} first."
		return
	fi
	#
	# Update script copies in "/tmp".
	#
	if [ -f "${SERVICE_MAIN_TMP}" ]; then 
		rm -f "${SERVICE_MAIN_TMP}"
	fi
	cat "${SERVICE_MAIN_SRC}" > "${SERVICE_MAIN_TMP}"
	#
	# Set executable and security permissions.
	#
	chmod +rx "${SERVICE_MAIN_TMP}"
	#
	# Run service instance.
	# 
	if [ -f "/bin/${SHELL_INTERPRETER}" ]; then
		echo "$0: Creating new service instance ..."
		set -m
		/bin/${SHELL_INTERPRETER} "${SERVICE_MAIN_TMP}" "${DEBUG_MODE}" > /dev/null &
	else
		echo "$0: Creating service instance FAILED. Install ${SHELL_INTERPRETER} first."
	fi
	return
}

findProcess ()
{
	# 
	# Usage: findProcess <ps result line>
	#
	# Purpose: Searches for previously set environment variable "LOOK_FOR_PROCESS".
	#
	# We got a line from ps similar to:
	# [ ]9396 nobody   13952 S    /usr/bin/httpd
	# 
	TEMP_RESULT=$(echo -n "$1" | grep -v grep | grep "$LOOK_FOR_PROCESS")
	#
	# Check if we found process specified in "LOOK_FOR_PROCESS".
	#
	if test "$TEMP_RESULT"; then
		#
		# Exclude our own PID from results.
		#
		MY_PID=$$
		GOT_PID=$(echo -n "$1" | sed 's/ \+/|/g' | sed 's/^|//' | cut -d '|' -f 1)
		if [ "$MY_PID" != "$GOT_PID" ]; then
			if [ "$NEED_SEPARATOR_ONCE" -eq "0" ]; then
				NEED_SEPARATOR_ONCE=1
			else
				echo -n " "
			fi
			echo -n "$GOT_PID"
		fi
	fi
	# 
	return
}
#
terminateOldInstances ()
{
	# 
	# Usage: terminateOldInstances <name_of_instance>
	# 
	
	# 
	# Detect and kill any previously running instances of this service.
	# 
	NEED_SEPARATOR_ONCE=0
	LOOK_FOR_PROCESS="$1"
	PS_LIST="$(ps w)"
	PROC_KILL_LIST=$(echo -e "$PS_LIST" | while read file; do findProcess "${file}"; done)
	if test "$PROC_KILL_LIST"; then
		echo "$0: Terminating old \"$LOOK_FOR_PROCESS\" instance(s) #$PROC_KILL_LIST ..."
		kill $PROC_KILL_LIST
	fi
	# 
	return
}
# ========================================
# ======== FUNCTTION BLOCK END =========
# ========================================
#
# ! Not supported on BusyBox routers.
#. /lib/lsb/init-functions
#
#
# Service instance control main.
#
DEBUG_MODE=""

case "$1" in
'debug')
		# Set DEBUG_MODE to ON.
		DEBUG_MODE="debug"
		;;
esac


case "$1" in
'start' | 'reset' | 'restart' | 'debug')
		sh $0 stop
		#
		# Run service main in a new instance.
		createInstance
		#
		exit 0
		;;
'stop')
		if [ -f "${SERVICE_PID_FILE}" ]; then
			kill -INT "$(cat "${SERVICE_PID_FILE}")"
			rm "${SERVICE_PID_FILE}"
		fi
		#
		terminateOldInstances "${SHELL_INTERPRETER} ${SERVICE_MAIN_TMP}"
		#
		# Remove FIFO to prevent "wrtpresence_main.sh" getting infinitely blocked.
		if [ -e "${SERVICE_EVENT_FIFO}" ]; then
			rm "${SERVICE_EVENT_FIFO}"
		fi
		exit 0
		;;
'showlog')
		# Show service log.
		tail -n 60 "${SERVICE_MAIN_LOG}"
		exit 0
		;;
'livelog')
		# Show service log with auto-refresh.
		clear
		while [ ! -f "${SERVICE_MAIN_LOG}" ]; do
			clear
			echo "[ERROR] Log ${SERVICE_MAIN_LOG} does not exist. Waiting ..."
			sleep 1
		done
		tail -f "${SERVICE_MAIN_LOG}"
		exit 0
		;;
'showstate')
		# Show content of state files.
		echo "*** associations.dto: =0 = PRESENT, >0 and <5 = PRESENT, disconnected, =5 = AWAY"
		cat "/tmp/associations.dto"
		echo ""
		#
		echo "*** present_devices.dto: Device names defined in main service script."
		cat "/tmp/present_devices.dto";
		echo ""
		#
		echo "*** wrtwifistareport last received unix time"
		grep ".*" /tmp/*.last_wrtwifistareport | sed -e "s/^\/tmp\///g" -e "s/\.last_wrtwifistareport//g"
		exit 0
		;;
'livestate')
		# Show content of state files with auto-refresh.
		clear
		while (true); do
			clear
			sh "$(readlink -f $0)" showstate
			sleep 1
		done
		exit 0
		;;
'diag')
		ps w | egrep "presence|tail|logread" | grep -v "grep" | grep -v "livelog" | grep -v "diag"
		exit 0
		;;
'ping')
		if [ -e "${SERVICE_EVENT_FIFO}" ]; then
			echo "$0: Sending PING to service fifoconsumer ..."
			echo "ping" >> "${SERVICE_EVENT_FIFO}"
		else
			echo "$0: [ERROR] Failed to send PING to service fifoconsumer, FIFO does not exist."
		fi
		exit 0
		;;
'clean')
		# rm -f "${SERVICE_MAIN_LOG}"
		rm -f "/tmp/associations.dto"
		rm -f "/tmp/present_devices.dto"
		# 
		echo "$0: [INFO] Cleanup done."
		exit 0
		;;		
esac
echo "Usage: $0 {start|debug|stop|reset|restart|showlog|livelog|showstate|livestate|diag|ping|clean}"
exit 0