implement SetCustomPeerSelector and ensure locking is good

TunnelPool.cpp

@@ -331,8 +331,12 @@ namespace tunnel
 		int numHops = isInbound ? m_NumInboundHops : m_NumOutboundHops;
 		// peers is empty
 		if (numHops <= 0) return true; 
-		// custom peer selector in use
-		if (m_CustomPeerSelector) return m_CustomPeerSelector->SelectPeers(peers, numHops, isInbound); 
+		// custom peer selector in use ?
+		{
+			std::lock_guard<std::mutex> lock(m_CustomPeerSelectorMutex);
+			if (m_CustomPeerSelector)
+					return m_CustomPeerSelector->SelectPeers(peers, numHops, isInbound);
+		}
 		// explicit peers in use
 		if (m_ExplicitPeers) return SelectExplicitPeers (peers, isInbound);
 
@@ -484,5 +488,22 @@ namespace tunnel
 		auto tunnel = tunnels.CreateInboundTunnel (std::make_shared<TunnelConfig>(outboundTunnel->GetInvertedPeers ()), outboundTunnel);
 		tunnel->SetTunnelPool (shared_from_this ());
 	}
+
+	void TunnelPool::SetCustomPeerSelector(TunnelPeerSelector selector)
+	{
+		std::lock_guard<std::mutex> lock(m_CustomPeerSelectorMutex);
+		m_CustomPeerSelector = selector;
+	}
+
+	void TunnelPool::UnsetCustomPeerSelector()
+	{
+		SetCustomPeerSelector(nullptr);
+	}
+
+	bool TunnelPool::HasCustomPeerSelector()
+	{
+		std::lock_guard<std::mutex> lock(m_CustomPeerSelectorMutex);
+		return m_CustomPeerSelector != nullptr;
+	}
 }
 }

TunnelPool.h

@@ -67,8 +67,8 @@ namespace tunnel
 			int GetNumOutboundTunnels () const { return m_NumOutboundTunnels; };
 
 			void SetCustomPeerSelector(TunnelPeerSelector selector);
-			TunnelPeerSelector GetCustomPeerSelector() const { return m_CustomPeerSelector; }
-    
+			void UnsetCustomPeerSelector();
+			bool HasCustomPeerSelector();
 		private:
 			
 			void CreateInboundTunnel ();	
@@ -92,6 +92,7 @@ namespace tunnel
 			mutable std::mutex m_TestsMutex;
 			std::map<uint32_t, std::pair<std::shared_ptr<OutboundTunnel>, std::shared_ptr<InboundTunnel> > > m_Tests;
 			bool m_IsActive;
+			std::mutex m_CustomPeerSelectorMutex;
 			TunnelPeerSelector m_CustomPeerSelector;
 		public: