Redo conversion of _networks to a vector. Just use a simple linear search and put the nwid in a pair with the pointer so linear search can be done without pointer chasing. This should be the fastest option for anything less than dozens of networks, and should save memory over the old map.

node/Node.cpp

@@ -141,7 +141,7 @@ Node::Node(
 Node::~Node()
 {
 	Mutex::Lock _l(_networks_m);
-	_networks.clear();
+	_networks.clear(); // ensure that networks are destroyed before shutdown
 	delete RR->sa;
 	delete RR->topology;
 	delete RR->antiRec;
@@ -236,14 +236,13 @@ ZT1_ResultCode Node::processBackgroundTasks(uint64_t now,volatile uint64_t *next
 			std::vector< SharedPtr<Network> > needConfig;
 			{
 				Mutex::Lock _l(_networks_m);
-				for(std::vector< SharedPtr<Network> >::const_iterator n(_networks.begin());n!=_networks.end();++n) {
-					SharedPtr<NetworkConfig> nc((*n)->config2());
-					if (((now - (*n)->lastConfigUpdate()) >= ZT_NETWORK_AUTOCONF_DELAY)||(!nc))
-						needConfig.push_back(*n);
+				for(std::vector< std::pair< uint64_t,SharedPtr<Network> > >::const_iterator n(_networks.begin());n!=_networks.end();++n) {
+					SharedPtr<NetworkConfig> nc(n->second->config2());
+					if (((now - n->second->lastConfigUpdate()) >= ZT_NETWORK_AUTOCONF_DELAY)||(!nc))
+						needConfig.push_back(n->second);
 					if (nc)
 						networkRelays.insert(networkRelays.end(),nc->relays().begin(),nc->relays().end());
 				}
-				std::sort(_networks.begin(),_networks.end());
 			}
 
 			// Request updated configuration for networks that need it
@@ -312,24 +311,21 @@ ZT1_ResultCode Node::join(uint64_t nwid)
 {
 	Mutex::Lock _l(_networks_m);
 	SharedPtr<Network> nw = _network(nwid);
-	if(!nw) {
-		_networks.push_back(SharedPtr<Network>(new Network(RR,nwid)));
-		std::sort(_networks.begin(),_networks.end());
-	}
+	if(!nw)
+		_networks.push_back(std::pair< uint64_t,SharedPtr<Network> >(nwid,SharedPtr<Network>(new Network(RR,nwid))));
+	std::sort(_networks.begin(),_networks.end()); // will sort by nwid since it's the first in a pair<>
 	return ZT1_RESULT_OK;
 }
 
 ZT1_ResultCode Node::leave(uint64_t nwid)
 {
+	std::vector< std::pair< uint64_t,SharedPtr<Network> > > newn;
 	Mutex::Lock _l(_networks_m);
-	std::vector< SharedPtr<Network> >::iterator nwi = std::lower_bound(_networks.begin(), _networks.end(), nwid, NetworkComparator());
-	if(nwi != _networks.end() && (*nwi)->id() == nwid) {
-		(*nwi)->destroy();
-		// erase element (replace by last)
-		*nwi = _networks.back();
-		_networks.pop_back();
-		std::sort(_networks.begin(),_networks.end());
+	for(std::vector< std::pair< uint64_t,SharedPtr<Network> > >::const_iterator n(_networks.begin());n!=_networks.end();++n) {
+		if (n->first != nwid)
+			newn.push_back(*n);
 	}
+	_networks.swap(newn);
 	return ZT1_RESULT_OK;
 }
 
@@ -432,8 +428,8 @@ ZT1_VirtualNetworkList *Node::networks() const
 	nl->networks = (ZT1_VirtualNetworkConfig *)(buf + sizeof(ZT1_VirtualNetworkList));
 
 	nl->networkCount = 0;
-	for(std::vector< SharedPtr<Network> >::const_iterator n(_networks.begin());n!=_networks.end();++n)
-		(*n)->externalConfig(&(nl->networks[nl->networkCount++]));
+	for(std::vector< std::pair< uint64_t,SharedPtr<Network> > >::const_iterator n(_networks.begin());n!=_networks.end();++n)
+		n->second->externalConfig(&(nl->networks[nl->networkCount++]));
 
 	return nl;
 }

node/Node.hpp

@@ -163,8 +163,11 @@ public:
 
 	inline std::vector< SharedPtr<Network> > allNetworks() const
 	{
+		std::vector< SharedPtr<Network> > nw;
 		Mutex::Lock _l(_networks_m);
-		std::vector< SharedPtr<Network> > nw(_networks);
+		nw.reserve(_networks.size());
+		for(std::vector< std::pair< uint64_t, SharedPtr<Network> > >::const_iterator i=_networks.begin();i!=_networks.end();++i)
+			nw.push_back(i->second);
 		return nw;
 	}
 
@@ -205,21 +208,14 @@ public:
 #endif
 
 private:
-	// for binary search on _networks
-	struct NetworkComparator {
-		bool operator()(const SharedPtr<Network> &n,uint64_t nwid) const {
-			return n->id() < nwid;
-		}
-	};
-
 	inline SharedPtr<Network> _network(uint64_t nwid) const
 	{
-		std::vector< SharedPtr<Network> >::const_iterator iter = std::lower_bound(_networks.begin(), _networks.end(), nwid, NetworkComparator());
-		if(iter != _networks.end() && (*iter)->id() == nwid) {
-			return *iter;
-		} else {
-			return SharedPtr<Network>();
+		// assumes _networks_m is locked
+		for(std::vector< std::pair< uint64_t, SharedPtr<Network> > >::const_iterator i=_networks.begin();i!=_networks.end();++i) {
+			if (i->first == nwid)
+				return i->second;
 		}
+		return SharedPtr<Network>();
 	}
 
 	RuntimeEnvironment _RR;
@@ -237,7 +233,7 @@ private:
 	//Dictionary _localConfig; // persisted as local.conf
 	//Mutex _localConfig_m;
 
-	std::vector< SharedPtr<Network> > _networks;
+	std::vector< std::pair< uint64_t, SharedPtr<Network> > > _networks;
 	Mutex _networks_m;
 
 	Mutex _backgroundTasksLock;