select high bandwidth routers for client tunnels

NetDb.cpp

@@ -785,22 +785,34 @@ namespace data
 		}	
 	}	
 
+	const RouterInfo * NetDb::GetRandomRouter () const
+	{
+		return GetRandomRouter (
+			[](const RouterInfo * router)->bool 
+			{ 
+				return !router->IsHidden (); 
+			});
+	}	
+	
 	const RouterInfo * NetDb::GetRandomRouter (const RouterInfo * compatibleWith) const
 	{
-		if (compatibleWith)
-			return GetRandomRouter (
-				[compatibleWith](const RouterInfo * router)->bool 
-				{ 
-					return !router->IsHidden () && router->IsCompatible (*compatibleWith); 
-				});
-		else
-			return GetRandomRouter (
-				[](const RouterInfo * router)->bool 
-				{ 
-					return !router->IsHidden (); 
-				});
+		return GetRandomRouter (
+			[compatibleWith](const RouterInfo * router)->bool 
+			{ 
+				return !router->IsHidden () && router->IsCompatible (*compatibleWith); 
+			});
 	}	
 
+	const RouterInfo * NetDb::GetHighBandwidthRandomRouter (const RouterInfo * compatibleWith) const
+	{
+		return GetRandomRouter (
+			[compatibleWith](const RouterInfo * router)->bool 
+			{ 
+				return !router->IsHidden () && router->IsCompatible (*compatibleWith) && 
+					(router->GetCaps () & RouterInfo::eHighBandwidth); 
+			});
+	}	
+	
 	template<typename Filter>
 	const RouterInfo * NetDb::GetRandomRouter (Filter filter) const
 	{

NetDb.h

@@ -79,8 +79,10 @@ namespace data
 			void HandleDatabaseSearchReplyMsg (I2NPMessage * msg);
 			void HandleDatabaseLookupMsg (I2NPMessage * msg);			
 
-			const RouterInfo * GetRandomRouter (const RouterInfo * compatibleWith = nullptr) const;
-
+			const RouterInfo * GetRandomRouter () const;
+			const RouterInfo * GetRandomRouter (const RouterInfo * compatibleWith) const;
+			const RouterInfo * GetHighBandwidthRandomRouter (const RouterInfo * compatibleWith) const;
+			
 			void PostI2NPMsg (I2NPMessage * msg);
 
 			// for web interface

TunnelPool.cpp

@@ -197,6 +197,15 @@ namespace tunnel
 			i2p::garlic::routing.PostI2NPMsg (msg);
 	}
 
+	const i2p::data::RouterInfo * TunnelPool::SelectNextHop (const i2p::data::RouterInfo * prevHop) const
+	{
+		auto hop = m_NumHops >= 3 ? i2p::data::netdb.GetHighBandwidthRandomRouter (prevHop) :
+			i2p::data::netdb.GetRandomRouter (prevHop);
+		if (!hop)
+			hop = i2p::data::netdb.GetRandomRouter ();
+		return hop;	
+	}	
+		
 	void TunnelPool::CreateInboundTunnel ()
 	{
 		OutboundTunnel * outboundTunnel = GetNextOutboundTunnel ();
@@ -219,7 +228,7 @@ namespace tunnel
 		}
 		for (int i = 0; i < numHops; i++)
 		{
-			auto hop = i2p::data::netdb.GetRandomRouter (prevHop);
+			auto hop = SelectNextHop (prevHop);
 			prevHop = hop;
 			hops.push_back (hop);
 		}		
@@ -251,7 +260,7 @@ namespace tunnel
 			std::vector<const i2p::data::RouterInfo *> hops;
 			for (int i = 0; i < m_NumHops; i++)
 			{
-				auto hop = i2p::data::netdb.GetRandomRouter (prevHop);
+				auto hop = SelectNextHop (prevHop);
 				prevHop = hop;
 				hops.push_back (hop);
 			}	
@@ -263,7 +272,7 @@ namespace tunnel
 		else
 			LogPrint ("Can't create outbound tunnel. No inbound tunnels found");
 	}	
-
+		
 	void TunnelPool::RecreateOutboundTunnel (OutboundTunnel * tunnel)
 	{
 		InboundTunnel * inboundTunnel = GetNextInboundTunnel ();

TunnelPool.h

@@ -7,6 +7,7 @@
 #include <utility>
 #include "Identity.h"
 #include "LeaseSet.h"
+#include "RouterInfo.h"
 #include "I2NPProtocol.h"
 #include "TunnelBase.h"
 #include "RouterContext.h"
@@ -53,6 +54,7 @@ namespace tunnel
 			template<class TTunnels>
 			typename TTunnels::value_type GetNextTunnel (TTunnels& tunnels, 
 				typename TTunnels::value_type suggested = nullptr);
+			const i2p::data::RouterInfo * SelectNextHop (const i2p::data::RouterInfo * prevHop) const;
 			
 		private: