change tunnels during stream resend attempts 5 and 6

libi2pd/Streaming.cpp

@@ -1024,34 +1024,31 @@ namespace stream
 			if (packets.size () > 0)
 			{
 				m_NumResendAttempts++;
-				if (m_RTO != INITIAL_RTO)
+				if (m_NumResendAttempts == 1 && m_RTO != INITIAL_RTO)
+				{
+					// congestion avoidance
 					m_RTO *= 2;
-				switch (m_NumResendAttempts)
+					m_WindowSize -= (m_WindowSize + WINDOW_SIZE_DROP_FRACTION) / WINDOW_SIZE_DROP_FRACTION; // adjustment >= 1
+					if (m_WindowSize < MIN_WINDOW_SIZE) m_WindowSize = MIN_WINDOW_SIZE;
+				}
+				else
 				{
-					case 1: // congestion avoidance
-						m_WindowSize -= (m_WindowSize + WINDOW_SIZE_DROP_FRACTION) / WINDOW_SIZE_DROP_FRACTION; // adjustment >= 1
-						if (m_WindowSize < MIN_WINDOW_SIZE) m_WindowSize = MIN_WINDOW_SIZE;
-					break;
-					case 2:
-						m_TunnelsChangeSequenceNumber = m_SequenceNumber;
-						m_RTO = INITIAL_RTO; // drop RTO to initial upon tunnels pair change first time
-#if (__cplusplus >= 201703L) // C++ 17 or higher
-						[[fallthrough]];
-#endif
-						// no break here
-					case 4:
-						if (m_RoutingSession) m_RoutingSession->SetSharedRoutingPath (nullptr);
-						UpdateCurrentRemoteLease (); // pick another lease
-						LogPrint (eLogWarning, "Streaming: Another remote lease has been selected for stream with rSID=", m_RecvStreamID, ", sSID=", m_SendStreamID);
-					break;
-					case 3:
+					m_TunnelsChangeSequenceNumber = m_SequenceNumber;
+					m_RTO = INITIAL_RTO; // drop RTO to initial upon tunnels pair change
+					if (m_RoutingSession) m_RoutingSession->SetSharedRoutingPath (nullptr);
+					if (m_NumResendAttempts & 1)
+					{
 						// pick another outbound tunnel
-						m_TunnelsChangeSequenceNumber = m_SequenceNumber;
-						if (m_RoutingSession) m_RoutingSession->SetSharedRoutingPath (nullptr);
 						m_CurrentOutboundTunnel = m_LocalDestination.GetOwner ()->GetTunnelPool ()->GetNextOutboundTunnel (m_CurrentOutboundTunnel);
-						LogPrint (eLogWarning, "Streaming: Another outbound tunnel has been selected for stream with sSID=", m_SendStreamID);
-					break;
-					default: ;
+						LogPrint (eLogWarning, "Streaming: Resend #", m_NumResendAttempts,
+							", another outbound tunnel has been selected for stream with sSID=", m_SendStreamID);
+					}
+					else
+					{
+						UpdateCurrentRemoteLease (); // pick another lease
+						LogPrint (eLogWarning, "Streaming: Resend #", m_NumResendAttempts,
+							", another remote lease has been selected for stream with rSID=", m_RecvStreamID, ", sSID=", m_SendStreamID);
+					}
 				}
 				SendPackets (packets);
 			}