#!/bin/sh

## Redirecting Filehanders
ln -sf /proc/$$/fd/1 /log/stdout.log
ln -sf /proc/$$/fd/2 /log/stderr.log

## Pre execution handler
pre_execution_handler() {
	## Pre Execution
	# TODO: put your pre execution steps here
	: # delete this nop
}

## Post execution handler
post_execution_handler() {
	## Post Execution
	# TODO: put your post execution steps here
	: # delete this nop
}

## Sigterm Handler
sigterm_handler() {
	if [ $pid -ne 0 ]; then
		# the above if statement is important because it ensures
		# that the application has already started. without it you
		# could attempt cleanup steps if the application failed to
		# start, causing errors.
		kill -15 "$pid"
		wait "$pid"
		post_execution_handler
	fi
	exit 143 # 128 + 15 -- SIGTERM
}

## Setup signal trap
# on callback execute the specified handler
trap 'sigterm_handler' SIGTERM

## Initialization
pre_execution_handler

## Start Process
# run process in background and record PID
"$@" >/log/stdout.log 2>/log/stderr.log &
pid="$!"
# Application can log to stdout/stderr, /log/stdout.log or /log/stderr.log

## Wait forever until app dies
wait "$pid"
return_code="$?"

## Cleanup
post_execution_handler
# echo the return code of the application
exit $return_code