supersede_lease
if (!(supersede_lease(lease, <, !offer ||
int supersede_lease(struct lease *, struct lease *, int);
supersede_lease(&address_range[lhost - i], lp, 0);
supersede_lease(comp, lease, 0);
supersede_lease(lease, <, 1);
supersede_lease(lease, <, 1);
supersede_lease(lease, lp, 1);