set ack requested flag after second resend attempt

libi2pd/RouterContext.cpp

@@ -34,7 +34,7 @@ namespace i2p
 		m_Error (eRouterErrorNone), m_ErrorV6 (eRouterErrorNone),
 		m_Testing (false), m_TestingV6 (false), m_NetID (I2PD_NET_ID),
 		m_PublishReplyToken (0), m_IsHiddenMode (false), 
-		m_Rng(i2p::util::GetMonotonicMicroseconds () % 1000000LL)
+		m_Rng(i2p::util::GetMonotonicMicroseconds () % 1000000LL), m_IsSaving (false)
 	{
 	}
 
@@ -78,12 +78,6 @@ namespace i2p
 			m_Service->Stop ();
 			CleanUp (); // GarlicDestination
 		}
-		if (m_SavingRouterInfo.valid ())
-		{	
-			m_SaveBuffer = nullptr;
-			m_SavingRouterInfo.get ();
-		}	
-		
 	}	
 
 	std::shared_ptr<i2p::data::RouterInfo::Buffer> RouterContext::CopyRouterInfoBuffer () const
@@ -271,14 +265,10 @@ namespace i2p
 			std::lock_guard<std::mutex> l(m_SaveBufferMutex);
 			m_SaveBuffer = buffer;
 		}
-		bool isSaving = m_SavingRouterInfo.valid (); 
-		if (isSaving && m_SavingRouterInfo.wait_for(std::chrono::seconds(0)) == std::future_status::ready)
-		{
-			m_SavingRouterInfo.get ();
-			isSaving = false;
-		}	
-		if (!isSaving) // try to save only if not being saved
-			m_SavingRouterInfo = std::async (std::launch::async, [this]() 
+		bool isSaving = false;
+		if (m_IsSaving.compare_exchange_strong (isSaving, true)) // try to save only if not being saved
+		{	
+			auto savingRouterInfo = std::async (std::launch::async, [this]() 
 				{
 					std::shared_ptr<i2p::data::RouterInfo::Buffer> buffer;
 					while (m_SaveBuffer)
@@ -291,7 +281,9 @@ namespace i2p
 						if (buffer)
 							i2p::data::RouterInfo::SaveToFile (i2p::fs::DataDirPath (ROUTER_INFO), buffer);
 					}	
+					m_IsSaving = false;
 				});
+		}	
 		m_LastUpdateTime = i2p::util::GetSecondsSinceEpoch ();
 	}
 

libi2pd/RouterContext.h

@@ -13,7 +13,6 @@
 #include <string>
 #include <memory>
 #include <random>
-#include <future>
 #include <unordered_set>
 #include <boost/asio.hpp>
 #include "Identity.h"
@@ -267,9 +266,9 @@ namespace garlic
 			bool m_IsHiddenMode; // not publish
 			mutable std::mutex m_RouterInfoMutex;
 			std::mt19937 m_Rng;
-			std::future<void> m_SavingRouterInfo;
 			std::shared_ptr<i2p::data::RouterInfo::Buffer> m_SaveBuffer;
 			std::mutex m_SaveBufferMutex; // TODO: make m_SaveBuffer atomic
+			std::atomic<bool> m_IsSaving;
 	};
 
 	extern RouterContext context;

libi2pd/SSU2Session.cpp

@@ -623,7 +623,8 @@ namespace transport
 				}
 				else
 				{
-					uint32_t packetNum = SendData (it->second->payload, it->second->payloadSize);
+					uint32_t packetNum = SendData (it->second->payload, it->second->payloadSize, 
+						it->second->numResends > 1 ? SSU2_FLAG_IMMEDIATE_ACK_REQUESTED : 0);
 					it->second->numResends++;
 					it->second->sendTime = ts;
 					resentPackets.emplace (packetNum, it->second);