remember tunnels selection for following messages

Garlic.cpp

@@ -125,6 +125,14 @@ namespace garlic
 			else 
 				it++;
 		}
+		CleanupUnconfirmedTags ();
+		return !m_SessionTags.empty () || !m_UnconfirmedTagsMsgs.empty ();
+ 	}
+
+	bool GarlicRoutingSession::CleanupUnconfirmedTags ()
+	{
+		bool ret = false;
+		uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
 		// delete expired unconfirmed tags
 		for (auto it = m_UnconfirmedTagsMsgs.begin (); it != m_UnconfirmedTagsMsgs.end ();)
 		{
@@ -133,12 +141,13 @@ namespace garlic
 				if (m_Owner)
 					m_Owner->RemoveDeliveryStatusSession ((*it)->msgID);
 				it = m_UnconfirmedTagsMsgs.erase (it);
+				ret = true;
 			}	
 			else
 				it++;
 		}	
-		return !m_SessionTags.empty () || !m_UnconfirmedTagsMsgs.empty ();
- 	}
+		return ret;
+	}
 
 	std::shared_ptr<I2NPMessage> GarlicRoutingSession::WrapSingleMessage (std::shared_ptr<const I2NPMessage> msg)
 	{
@@ -625,7 +634,7 @@ namespace garlic
 				it++;
 		}
 	}
-	
+
 	void GarlicDestination::RemoveDeliveryStatusSession (uint32_t msgID)
 	{
 		m_DeliveryStatusSessions.erase (msgID);

Garlic.h

@@ -98,6 +98,7 @@ namespace garlic
 			std::shared_ptr<I2NPMessage> WrapSingleMessage (std::shared_ptr<const I2NPMessage> msg);
 			void MessageConfirmed (uint32_t msgID);
 			bool CleanupExpiredTags (); // returns true if something left 
+			bool CleanupUnconfirmedTags (); // returns true if something has been deleted
 
 			void SetLeaseSetUpdated () 
 			{ 

I2CP.cpp

@@ -87,23 +87,51 @@ namespace client
 	}
 
 	bool I2CPDestination::SendMsg (std::shared_ptr<I2NPMessage> msg, std::shared_ptr<const i2p::data::LeaseSet> remote)
-	{
-		auto outboundTunnel = GetTunnelPool ()->GetNextOutboundTunnel ();
-		auto leases = remote->GetNonExpiredLeases ();
-		if (!leases.empty () && outboundTunnel)
+	{	
+		auto remoteSession = GetRoutingSession (remote, true); 	
+		if (!remoteSession)
+		{
+			LogPrint (eLogError, "I2CP: Failed to create remote session");
+			return false;
+		}
+		auto path = remoteSession->GetSharedRoutingPath ();
+		std::shared_ptr<i2p::tunnel::OutboundTunnel> outboundTunnel;
+		std::shared_ptr<const i2p::data::Lease> remoteLease;	
+		if (path)
+		{
+			if (!remoteSession->CleanupUnconfirmedTags ()) // no stuck tags
+			{
+				outboundTunnel = path->outboundTunnel;
+				remoteLease = path->remoteLease;
+			}
+			else
+				remoteSession->SetSharedRoutingPath (nullptr);
+		}
+		else
+		{
+			auto outboundTunnel = GetTunnelPool ()->GetNextOutboundTunnel ();
+			auto leases = remote->GetNonExpiredLeases ();
+			if (!leases.empty ())		
+				remoteLease = leases[rand () % leases.size ()];
+			if (remoteLease && outboundTunnel)
+				remoteSession->SetSharedRoutingPath (std::make_shared<i2p::garlic::GarlicRoutingPath> (
+					i2p::garlic::GarlicRoutingPath{outboundTunnel, remoteLease, 10000, 0, 0})); // 10 secs RTT
+			else
+				remoteSession->SetSharedRoutingPath (nullptr);
+		}	
+		if (remoteLease && outboundTunnel)
 		{
 			std::vector<i2p::tunnel::TunnelMessageBlock> msgs;			
-			uint32_t i = rand () % leases.size ();
-			auto garlic = WrapMessage (remote, msg, true);
+			auto garlic = remoteSession->WrapSingleMessage (msg);
 			msgs.push_back (i2p::tunnel::TunnelMessageBlock 
 				{ 
 					i2p::tunnel::eDeliveryTypeTunnel,
-					leases[i]->tunnelGateway, leases[i]->tunnelID,
+					remoteLease->tunnelGateway, remoteLease->tunnelID,
 					garlic
 				});
 			outboundTunnel->SendTunnelDataMsg (msgs);
 			return true;
-		}
+		}		
 		else
 		{
 			if (outboundTunnel)