static gint compare_expire(gconstpointer a, gconstpointer b)
{
	const struct dhcp_lease *lease1 = a;
	const struct dhcp_lease *lease2 = b;

	return lease2->expire - lease1->expire;
}
static gint compare_expire(gconstpointer a, gconstpointer b)
{
	const struct dhcp_lease *lease1 = a;
	const struct dhcp_lease *lease2 = b;

	return lease2->expire - lease1->expire;
}