shutdownbutton

#!/bin/bash
# required package:
# apt-get install raspi-gpio
##### edit area start
scriptver="V1.5"
gpionum=24
cnt4shutdown=3
logf="/var/log/shutdownbutton.log"
# cnt*1000ms 3sec -> 3
##### edit area end
#
function DO_shutdown {
	echo "Shutting Down..."
	sudo shutdown -h now
	/bin/sleep 30
}

function Switch_GPIO {
# signal ATtiny to shutoff within next 20secs and do a shutdown
	if [ "$gpionum" != "" ]; then
        	echo "Signal PWRcontroller to power off..."
        	/usr/bin/raspi-gpio set $gpionum op pn dl
        	/bin/sleep 4
        	/usr/bin/raspi-gpio set $gpionum op pn dh
        	/usr/bin/raspi-gpio set $gpionum ip pu
	else
		echo "no GPIO for PowerOff signaling defined..."
	fi
}

function Poll_GPIO {
# poll GPIO for minimum 3 sec low signal and do shutdown
	echo "Poll_GPIO START"
	/usr/bin/raspi-gpio set $gpionum ip pu
	counter=0
	while true; do
 		gpiolvl=$(/usr/bin/raspi-gpio get $gpionum | awk '{print $3;}')
#		echo "gpiolvl: $gpiolvl"
		if [ "$gpiolvl" == "level=0" ] ; then
			echo "Button pressed ($gpiolvl)..."
			((counter = counter + 1))
			if [ "$counter" -ge "$cnt4shutdown" ] ; then
#				/bin/sleep 3
				DO_shutdown
				counter=0
			fi
 		else
			counter=0
 		fi
 		/bin/sleep 1
	done
}

function Create_service_file1 {
	fil="/lib/systemd/system/shutdownbutton.service"

	cat <<EOF > "$fil"
[Unit]
Description=ShutdownButton Service
After=multi-user.target

[Service]
Type=idle
ExecStart=/usr/local/sbin/shutdownbutton pollgpio
ExecStop=/usr/local/sbin/shutdownbutton settletime
StandardOutput=syslog
StandardError=syslog
SyslogIdentifier=ShutdownButton

[Install]
WantedBy=multi-user.target
Alias=shutdownbutton.service
EOF

	chmod 644 "$fil"
	chown root:root "$fil"
}

function Create_service_file2 {
        fil="/lib/systemd/system/shutdownbuttonswitch.service"

        cat <<EOF > "$fil"
[Unit]
Description=ShutdownButtonSwitch Service
DefaultDependencies=no
Before=poweroff.target halt.target

[Service]
Type=oneshot
ExecStart=/usr/local/sbin/shutdownbutton switchoff
RemainAfterExit=yes
StandardOutput=syslog
StandardError=syslog
SyslogIdentifier=ShutdownButtonSwitch

[Install]
WantedBy=poweroff.target halt.target
Alias=shutdownbuttonswitch.service
EOF

        chmod 644 "$fil"
        chown root:root "$fil"
}

function DO_install {
#	apt -qy update
	apt install -qy raspi-gpio
	Create_service_file1
	Create_service_file2
	systemctl daemon-reload
	systemctl enable shutdownbutton.service
	systemctl enable shutdownbuttonswitch.service
}

# echo "start $0 $1 $2 $2"

case "$1" in
	install)
		DO_install
		;;
	switchoff)
		Switch_GPIO
#		DO_shutdown
		;;
	pollgpio)
		Poll_GPIO
		;;
        settletime)
		echo "settletime"
		/bin/sleep 4
                ;;
	version)
		echo "$scriptver"
		;;
	*)
		echo "$(basename $0) unknown option $1 $2 $3 $4"
		echo "Usage: $(basename $0) switchoff | install | version"
		exit 1
esac