#!/bin/sh

SAMBA_DHCP_CONF=/var/lib/samba/dhcp.conf

netbios_setup() {
	# No need to continue if we're called with an unsupported option

	case $reason in
	BOUND|RENEW|REBIND|REBOOT|EXPIRE|FAIL|RELEASE|STOP)
		;;
	*)
		return
		;;
	esac

	umask 022

	local other_servers=""
	local serverlist=""

	# the destination file won't exist yet on the first run after 
	# installing samba
	if [ -e $SAMBA_DHCP_CONF ] && [ -s $SAMBA_DHCP_CONF ]
	then
		# don't continue if no settings have changed
		if [ "$new_netbios_name_servers" = "$old_netbios_name_servers" ] \
		   && [ "$new_netbios_scope" = "$old_netbios_scope" ] \
		   && [ -n "$new_netbios_name_servers" ]
		then
			return
		fi

		# reparse our own file
		other_servers=`sed -n -e"s/[[:space:]]$interface:[^[:space:]]*//g; \
			s/^[[:space:]]*wins server[[:space:]]*=[[:space:]]*//pi" \
			$SAMBA_DHCP_CONF`

		serverlist="$other_servers"
	fi

	for server in $new_netbios_name_servers
	do
		serverlist="$serverlist $interface:$server"
	done

	echo -n > ${SAMBA_DHCP_CONF}.new

	# If we're updating on failure/expire, AND there are no WINS
	# servers for other interfaces, leave the file empty.
	if [ -z "$other_servers" ]
	then
		if [ "$reason" = FAIL ] || [ "$reason" = EXPIRE ]
		then
			mv ${SAMBA_DHCP_CONF}.new $SAMBA_DHCP_CONF
			return
		fi
	fi

	if [ -n "$serverlist" ]
	then
		echo "   wins server =$serverlist" >> ${SAMBA_DHCP_CONF}.new
	fi
	if [ -n "$new_netbios_scope" ]
	then
		echo "   netbios scope = $new_netbios_scope" >> ${SAMBA_DHCP_CONF}.new
	fi
	mv ${SAMBA_DHCP_CONF}.new $SAMBA_DHCP_CONF

	# reload the samba server
	# We don't necessarily have the samba package installed. #414841
	if [ -x /etc/init.d/smbd ]
	then
		if [ -d /run/systemd/system ]
		then
			if systemctl is-enabled smbd.service --quiet
			then
				systemctl try-reload-or-restart smbd.service
			fi
		else
			/usr/sbin/invoke-rc.d smbd reload
		fi
	fi
}

netbios_setup