/*
* Remove dead nodes
*/
bool KBucket::checkExpiration(uint64_t currentTime)
{
bool dirty = false;
// we should ping oldest node from every bucket here
// but since we have only one bucket now, simulate it by pinging more nodes
unsigned int pingCount = max(K, min((int)2 * K, (int)(nodes.size() / (K * 10)) + 1)); // <-- pings 10 - 20 oldest nodes
unsigned int pinged = 0;
dcdrun(unsigned int removed = 0);
// first, remove dead nodes
NodeList::iterator i = nodes.begin();
while(i != nodes.end())
{
Node::Ptr& node = *i;
if(node->getType() == 4 && node->expires > 0 && node->expires <= currentTime)
{
if(node->unique(2))
{
// node is dead, remove it
string ip = node->getIdentity().getIp();
string port = node->getIdentity().getUdpPort();
ipMap.erase(ip + ":" + port);
if(node->isOnline())
{
ClientManager::getInstance()->putOffline(node.get());
node->dec();
}
i = nodes.erase(i);
dirty = true;
dcdrun(removed++);
}
else
{
++i;
}
continue;
}
if(node->expires == 0)
node->expires = currentTime;
// select the oldest expired node
if(pinged < pingCount && node->getType() < 4 && node->expires <= currentTime)
{
// ping the oldest (expired) node
node->setTimeout(currentTime);
DHT::getInstance()->info(node->getIdentity().getIp(), static_cast<uint16_t>(Util::toInt(node->getIdentity().getUdpPort())), DHT::PING, node->getUser()->getCID(), node->getUdpKey());
pinged++;
}
++i;
}
#ifdef _DEBUG
int verified = 0; int types[5] = { 0 };
for(NodeList::const_iterator j = nodes.begin(); j != nodes.end(); j++)
{
Node::Ptr n = *j;
if(n->isIpVerified()) verified++;
dcassert(n->getType() >= 0 && n->getType() <= 4);
types[n->getType()]++;
}
dcdebug("DHT Nodes: %d (%d verified), Types: %d/%d/%d/%d/%d, pinged %d of %d, removed %d\n", nodes.size(), verified, types[0], types[1], types[2], types[3], types[4], pinged, pingCount, removed);
#endif
return dirty;
}
/*
* Creates new (or update existing) node which is NOT added to our routing table
*/
Node::Ptr KBucket::createNode(const UserPtr& u, const string& ip, uint16_t port, bool update, bool isUdpKeyValid)
{
if(u->isSet(User::DHT)) // is this user already known in DHT?
{
Node::Ptr node = NULL;
// no online node found, try get from routing table
for(NodeList::iterator it = nodes.begin(); it != nodes.end(); ++it)
{
if(u->getCID() == (*it)->getUser()->getCID())
{
node = *it;
// put node at the end of the list
nodes.erase(it);
nodes.push_back(node);
break;
}
}
if(node == NULL && u->isOnline())
{
// try to get node from ClientManager (user can be online but not in our routing table)
// this fixes the bug with DHT node online twice
node = (Node*)ClientManager::getInstance()->findDHTNode(u->getCID());
node = node.get();
}
if(node != NULL)
{
// fine, node found, update it and return it
if(update)
{
string oldIp = node->getIdentity().getIp();
string oldPort = node->getIdentity().getUdpPort();
if(ip != oldIp || static_cast<uint16_t>(Util::toInt(oldPort)) != port)
{
node->setIpVerified(false);
// TODO: don't allow update when new IP already exists for different node
// erase old IP and remember new one
ipMap.erase(oldIp + ":" + oldPort);
ipMap.insert(ip + ":" + Util::toString(port));
}
if(!node->isIpVerified())
node->setIpVerified(isUdpKeyValid);
node->setAlive();
node->getIdentity().setIp(ip);
node->getIdentity().setUdpPort(Util::toString(port));
DHT::getInstance()->setDirty();
}
return node;
}
}
u->setFlag(User::DHT);
Node::Ptr node(new Node(u));
node->getIdentity().setIp(ip);
node->getIdentity().setUdpPort(Util::toString(port));
node->setIpVerified(isUdpKeyValid);
return node;
}