Code cleanup, and fix some unsafe pointer handling in Network.

node/Network.cpp

@@ -535,15 +535,11 @@ void Network::threadMain()
 
 void Network::_CBhandleTapData(void *arg,const MAC &from,const MAC &to,unsigned int etherType,const Buffer<4096> &data)
 {
-	if ((!((Network *)arg)->_enabled)||(((Network *)arg)->status() != NETWORK_OK))
+	SharedPtr<Network> network((Network *)arg,true);
+	if ((!network)||(!network->_enabled)||(network->status() != NETWORK_OK))
 		return;
-
-	const RuntimeEnvironment *RR = ((Network *)arg)->RR;
-	if (RR->shutdownInProgress)
-		return;
-
 	try {
-		RR->sw->onLocalEthernet(SharedPtr<Network>((Network *)arg),from,to,etherType,data);
+		network->RR->sw->onLocalEthernet(network,from,to,etherType,data);
 	} catch (std::exception &exc) {
 		TRACE("unexpected exception handling local packet: %s",exc.what());
 	} catch ( ... ) {

node/Node.cpp

@@ -99,8 +99,6 @@ struct _NodeImpl
 		RuntimeEnvironment *RR = &renv;
 		LOG("terminating: %s",reasonForTerminationStr.c_str());
 
-		renv.shutdownInProgress = true;
-
 		running = false;
 
 #ifndef __WINDOWS__
@@ -109,9 +107,9 @@ struct _NodeImpl
 		delete renv.updater;  renv.updater = (SoftwareUpdater *)0;
 		delete renv.nc;       renv.nc = (NodeConfig *)0;            // shut down all networks, close taps, etc.
 		delete renv.topology; renv.topology = (Topology *)0;        // now we no longer need routing info
-		delete renv.sw;       renv.sw = (Switch *)0;                // order matters less from here down
 		delete renv.mc;       renv.mc = (Multicaster *)0;
 		delete renv.antiRec;  renv.antiRec = (AntiRecursion *)0;
+		delete renv.sw;       renv.sw = (Switch *)0;                // order matters less from here down
 		delete renv.http;     renv.http = (HttpClient *)0;
 		delete renv.prng;     renv.prng = (CMWC4096 *)0;
 		delete renv.log;      renv.log = (Logger *)0;               // but stop logging last of all
@@ -271,16 +269,12 @@ Node::~Node()
 
 static void _CBztTraffic(const SharedPtr<Socket> &fromSock,void *arg,const InetAddress &from,Buffer<ZT_SOCKET_MAX_MESSAGE_LEN> &data)
 {
-	const RuntimeEnvironment *RR = (const RuntimeEnvironment *)arg;
-	if ((RR->sw)&&(!RR->shutdownInProgress))
-		RR->sw->onRemotePacket(fromSock,from,data);
+	((const RuntimeEnvironment *)arg)->sw->onRemotePacket(fromSock,from,data);
 }
 
 static void _cbHandleGetRootTopology(void *arg,int code,const std::string &url,const std::string &body)
 {
 	RuntimeEnvironment *RR = (RuntimeEnvironment *)arg;
-	if (RR->shutdownInProgress)
-		return;
 
 	if ((code != 200)||(body.length() == 0)) {
 		TRACE("failed to retrieve %s",url.c_str());
@@ -391,9 +385,9 @@ Node::ReasonForTermination Node::run()
 		}
 
 		RR->http = new HttpClient();
-		RR->antiRec = new AntiRecursion();
-		RR->mc = new Multicaster(RR);
 		RR->sw = new Switch(RR);
+		RR->mc = new Multicaster(RR);
+		RR->antiRec = new AntiRecursion();
 		RR->topology = new Topology(RR);
 		try {
 			RR->nc = new NodeConfig(RR);

node/NodeConfig.hpp

@@ -145,7 +145,7 @@ public:
 	inline bool hasNetwork(uint64_t nwid)
 	{
 		Mutex::Lock _l(_networks_m);
-		return (_networks.count(nwid) > 0);
+		return (_networks.find(nwid) != _networks.end());
 	}
 
 	/**
@@ -163,12 +163,15 @@ public:
 		return tapDevs;
 	}
 
+private:
 	void _readLocalConfig();
 	void _writeLocalConfig();
 
 	const RuntimeEnvironment *RR;
+
 	Dictionary _localConfig; // persisted as local.conf
 	Mutex _localConfig_m;
+
 	std::map< uint64_t,SharedPtr<Network> > _networks; // persisted in networks.d/
 	Mutex _networks_m;
 };

node/RuntimeEnvironment.hpp

@@ -69,7 +69,6 @@ public:
 		homePath(),
 		identity(),
 		initialized(false),
-		shutdownInProgress(false),
 		tcpTunnelingEnabled(false),
 		timeOfLastResynchronize(0),
 		timeOfLastPacketReceived(0),
@@ -79,9 +78,9 @@ public:
 		log((Logger *)0),
 		prng((CMWC4096 *)0),
 		http((HttpClient *)0),
-		antiRec((AntiRecursion *)0),
-		mc((Multicaster *)0),
 		sw((Switch *)0),
+		mc((Multicaster *)0),
+		antiRec((AntiRecursion *)0),
 		topology((Topology *)0),
 		nc((NodeConfig *)0),
 		node((Node *)0),
@@ -101,9 +100,6 @@ public:
 	// Are we initialized?
 	volatile bool initialized;
 
-	// Indicates that we are shutting down -- this is hacky, want to factor out
-	volatile bool shutdownInProgress;
-
 	// Are we in outgoing TCP failover mode?
 	volatile bool tcpTunnelingEnabled;
 
@@ -130,9 +126,9 @@ public:
 	Logger *log; // null if logging is disabled
 	CMWC4096 *prng;
 	HttpClient *http;
-	AntiRecursion *antiRec;
-	Multicaster *mc;
 	Switch *sw;
+	Multicaster *mc;
+	AntiRecursion *antiRec;
 	Topology *topology;
 	NodeConfig *nc;
 	Node *node;

node/SharedPtr.hpp

@@ -64,6 +64,20 @@ public:
 		++obj->__refCount;
 	}
 
+	SharedPtr(T *obj,bool runAwayFromZombies)
+		throw() :
+		_ptr(obj)
+	{
+		// HACK: this is used in "handlers" to take ownership of naked pointers,
+		// an ugly pattern that really ought to be factored out.
+		if (runAwayFromZombies) {
+			if ((int)(++obj->__refCount) < 2) {
+				--obj->__refCount;
+				_ptr = (T *)0;
+			}
+		} else ++obj->__refCount;
+	}
+
 	SharedPtr(const SharedPtr &sp)
 		throw() :
 		_ptr(sp._getAndInc())