* check router info addresses for nullptr

* Request LS before expiration for smoother handover

Destination.cpp

@@ -171,11 +171,29 @@ namespace client
 
 	std::shared_ptr<const i2p::data::LeaseSet> LeaseSetDestination::FindLeaseSet (const i2p::data::IdentHash& ident)
 	{
+		std::lock_guard<std::mutex> lock(m_RemoteLeaseSetsMutex);
 		auto it = m_RemoteLeaseSets.find (ident);
 		if (it != m_RemoteLeaseSets.end ())
 		{
 			if (!it->second->IsExpired ())
+			{
+				if (it->second->ExpiresSoon())
+				{
+					LogPrint(eLogDebug, "Destination: Lease Set expires soon, updating before expire");
+					// update now before expiration for smooth handover
+					RequestDestination(ident, [this, ident] (std::shared_ptr<i2p::data::LeaseSet> ls) {
+						if(ls && !ls->IsExpired())
+						{
+							ls->PopulateLeases();
+							{
+								std::lock_guard<std::mutex> _lock(m_RemoteLeaseSetsMutex);
+								m_RemoteLeaseSets[ident] = ls;
+							}
+						}
+					});
+				}
 				return it->second;
+			}
 			else
 				LogPrint (eLogWarning, "Destination: remote LeaseSet expired");
 		}	
@@ -185,7 +203,10 @@ namespace client
 			if (ls && !ls->IsExpired ())
 			{
 				ls->PopulateLeases (); // since we don't store them in netdb
-				m_RemoteLeaseSets[ident] = ls;			
+				{
+					std::lock_guard<std::mutex> lock(m_RemoteLeaseSetsMutex);
+					m_RemoteLeaseSets[ident] = ls;
+				}
 				return ls;
 			}	
 		}
@@ -279,6 +300,7 @@ namespace client
 		if (buf[DATABASE_STORE_TYPE_OFFSET] == 1) // LeaseSet
 		{
 			LogPrint (eLogDebug, "Remote LeaseSet");
+			std::lock_guard<std::mutex> lock(m_RemoteLeaseSetsMutex);
 			auto it = m_RemoteLeaseSets.find (buf + DATABASE_STORE_KEY_OFFSET);
 			if (it != m_RemoteLeaseSets.end ())
 			{
@@ -627,6 +649,7 @@ namespace client
 	void LeaseSetDestination::CleanupRemoteLeaseSets ()
 	{
 		auto ts = i2p::util::GetMillisecondsSinceEpoch ();
+		std::lock_guard<std::mutex> lock(m_RemoteLeaseSetsMutex);
 		for (auto it = m_RemoteLeaseSets.begin (); it != m_RemoteLeaseSets.end ();)
 		{
 			if (it->second->IsEmpty () || ts > it->second->GetExpirationTime ()) // leaseset expired

Destination.h

@@ -122,6 +122,7 @@ namespace client
 			std::thread * m_Thread;	
 			boost::asio::io_service m_Service;
 			boost::asio::io_service::work m_Work;
+			mutable std::mutex m_RemoteLeaseSetsMutex;
 			std::map<i2p::data::IdentHash, std::shared_ptr<i2p::data::LeaseSet> > m_RemoteLeaseSets;
 			std::map<i2p::data::IdentHash, std::shared_ptr<LeaseSetRequest> > m_LeaseSetRequests;
 

LeaseSet.cpp

@@ -163,6 +163,13 @@ namespace data
 		return ExtractTimestamp (buf, len) > ExtractTimestamp (m_Buffer, m_BufferLen);
 	}	
 
+	bool LeaseSet::ExpiresSoon(const uint64_t dlt) const
+	{
+		auto now = i2p::util::GetMillisecondsSinceEpoch ();
+		if (now >= m_ExpirationTime) return true;
+		return	m_ExpirationTime - now <= dlt;
+	}
+	
 	const std::vector<std::shared_ptr<const Lease> > LeaseSet::GetNonExpiredLeases (bool withThreshold) const
 	{
 		auto ts = i2p::util::GetMillisecondsSinceEpoch ();

LeaseSet.h

@@ -60,6 +60,7 @@ namespace data
 			bool IsExpired () const;
 			bool IsEmpty () const { return m_Leases.empty (); };
 			uint64_t GetExpirationTime () const { return m_ExpirationTime; };
+			bool ExpiresSoon(const uint64_t dlt=1000 * 5) const ;
 			bool operator== (const LeaseSet& other) const 
 			{ return m_BufferLen == other.m_BufferLen && !memcmp (m_Buffer, other.m_Buffer, m_BufferLen); }; 
 

NTCPSession.cpp

@@ -768,6 +768,7 @@ namespace transport
 			auto& addresses = context.GetRouterInfo ().GetAddresses ();
 			for (auto address: addresses)
 			{
+				if (!address) continue;
 				if (address->transportStyle == i2p::data::RouterInfo::eTransportNTCP)
 				{
 					if (address->host.is_v4())

Transports.cpp

@@ -114,6 +114,7 @@ namespace transport
 		auto& addresses = context.GetRouterInfo ().GetAddresses ();
 		for (auto address : addresses)
 		{
+			if (!address) continue;
 			if (m_NTCPServer == nullptr && enableNTCP)
 			{
 				m_NTCPServer = new NTCPServer ();