RoutingTableEntryList RoutingTable::getPossibleNextHops(const Packet* packet) {
if (isDeliverable(packet->getDestination())) {
AddressPtr source = packet->getSource();
AddressPtr sender = packet->getSender();
RoutingTableEntryList* availableHops = table[packet->getDestination()];
RoutingTableEntryList returnedList = RoutingTableEntryList(*availableHops);
// remove all entries that would route the packet back over the source or sender of the packet (would create a loop)
RoutingTableEntryList::iterator iterator = returnedList.begin();
while (iterator != returnedList.end()) {
RoutingTableEntry* entry = *iterator;
AddressPtr possibleNextHop = entry->getAddress();
if (possibleNextHop->equals(source) || possibleNextHop->equals(sender) ) {
iterator = returnedList.erase(iterator);
}
else {
iterator++;
}
}
return returnedList;
}
else {
// return empty list
return RoutingTableEntryList();
}
}
void RoutingTable::removeEntry(AddressPtr destination, AddressPtr nextHop, NetworkInterface* interface) {
if (table.find(destination) != table.end()) {
RoutingTableEntryList* entryList = table[destination];
RoutingTableEntryList::iterator iterator = entryList->begin();
if (iterator != entryList->end()) {
while (iterator != entryList->end()) {
RoutingTableEntry* entry = *iterator;
if (entry->getAddress()->equals(nextHop) && entry->getNetworkInterface()->equals(interface)) {
entryList->erase(iterator);
delete entry;
break;
}
iterator++;
}
if (entryList->empty()) {
// this was the last entry so we can delete the whole list
table.erase(destination);
delete entryList;
}
}
}
}