Example #1
0
func (sm *SubnetManager) allocateSubnet() (ip.IP4Net, error) {
	log.Infof("Picking subnet in range %s ... %s", sm.config.SubnetMin, sm.config.SubnetMax)

	var bag []ip.IP4
	sn := ip.IP4Net{IP: sm.config.SubnetMin, PrefixLen: sm.config.SubnetLen}

OuterLoop:
	for ; sn.IP <= sm.config.SubnetMax && len(bag) < 100; sn = sn.Next() {
		for _, l := range sm.leases {
			if sn.Overlaps(l.Network) {
				continue OuterLoop
			}
		}
		bag = append(bag, sn.IP)
	}

	if len(bag) == 0 {
		return ip.IP4Net{}, errors.New("out of subnets")
	} else {
		i := randInt(0, len(bag))
		return ip.IP4Net{IP: bag[i], PrefixLen: sm.config.SubnetLen}, nil
	}
}