#!/bin/sh
### BEGIN INIT INFO
# Provides:          brintos-network
# Required-Start:
# Required-Stop:
# Default-Start:     S
# Default-Stop:
# Short-Description: Static address and default route on the virtio-net interface
### END INIT INFO

PATH=/sbin:/usr/sbin:/bin:/usr/bin

IFACE=eth0
ADDRESS=10.0.2.15/24
GATEWAY=10.0.2.2
[ -r /etc/default/brintos-network ] && . /etc/default/brintos-network

# BRINTOS-WORKAROUND: brintos/linux#16 revisit -- drives ip directly because ifup failed to take its ifstate lock while advisory locks returned EINVAL
present() {
	ip link show "$IFACE" >/dev/null 2>&1
}

has_address() {
	ip -4 addr show dev "$IFACE" 2>/dev/null | grep -qF "inet $ADDRESS "
}

has_default() {
	ip route show 2>/dev/null | grep -q '^default '
}

# ip's netlink adds are exclusive, so each is guarded on the current state: a
# configured link would otherwise print "File exists" on every boot. The adds
# keep their stderr; only the probes are quiet.
start() {
	if ! present; then
		echo "brintos-network: no $IFACE (no virtio-net device) -- network not configured"
		return 0
	fi
	ip link set "$IFACE" up || return 1
	has_address || ip addr add "$ADDRESS" dev "$IFACE" || return 1
	has_default || ip route add default via "$GATEWAY" dev "$IFACE" || return 1
	echo "brintos-network: $IFACE up, $ADDRESS via $GATEWAY"
}

stop() {
	present || return 0
	ip route show 2>/dev/null | grep -q "^default via $GATEWAY " &&
		ip route del default via "$GATEWAY"
	has_address && ip addr del "$ADDRESS" dev "$IFACE"
	ip link set "$IFACE" down
}

status() {
	if ! present; then
		echo "brintos-network: no $IFACE"
		return 3
	fi
	ip addr show dev "$IFACE"
	ip route show
	has_address && has_default || return 3
}

case "$1" in
	start|stop|status)
		"$1"
		;;
	restart)
		stop
		start
		;;
	*)
		echo "Usage: $0 {start|stop|restart|status}" >&2
		exit 2
		;;
esac