EC: forward CLibSocket::OnLost to CECSocket::OnLost so EOF actually flips the UI

got3nks · got3nks · commit 48a98504af71 · 2026-05-28T15:51:51.000+02:00
CECMuleSocket multi-inherits from CECSocket (EC protocol layer) and CLibSocket (transport layer). Both declare `virtual void OnLost()` with identical signature, so they live in separate vtables in the combined object and there's no shared override. The Asio reactor's HandleRead (LibSocketAsio.cpp) calls socket->OnLost() through the CLibSocket vtable on EOF / peer-FIN — but that vtable slot is the empty CLibSocket::OnLost(){} default, because nothing was overriding the LibSocket-side virtual. CRemoteConnect::OnLost and CECServerSocket::OnLost (the ones that actually flip the GUI to disconnected and release server-side state) override the *CECSocket* side and never get called from the Asio path. End result on the wire: amuled closes the EC socket, amulegui / amuleweb's kernel receives FIN and parks the socket in CLOSE_WAIT, the Asio reactor reports EOF, dispatch lands in the empty stub, and the client process happily sits "connected" forever. Verified live on a Linux VM in this branch's previous keepalive-only commit — the TCP-layer teardown via keepalive eventually fires (~60s) but application-level state never reacts. Fix mirrors the existing OnConnect(int) pattern in CECMuleSocket: disambiguate by signature. * CLibSocket::OnLost() → OnLost(int) (param ignored, exists only to give the LibSocket-side virtual a different signature from the EC-side one). * LibSocketAsio.cpp dispatch updated to call OnLost(0). * CWebSocket::OnLost overrides on the new signature (amuleweb's HTTP-side socket inherits CLibSocket directly so this is the right hook there). * New CECMuleSocket::OnLost(int) forwards to CECSocket::OnLost() through a static_cast<CECSocket*>(this) call so virtual dispatch finds the most-derived override (CRemoteConnect on amulegui / amuleweb's EC side, CECServerSocket on amuled). Refs amule-project#757.
diff --git a/src/LibSocket.h b/src/LibSocket.h
@@ -132,7 +132,14 @@ class CLibSocket
 	virtual void OnConnect(int) {}
 	virtual void OnSend(int) {}
 	virtual void OnReceive(int) {}
-	virtual void OnLost() {}
+	// Int argument is unused — exists to give the CLibSocket-layer
+	// hook a different signature from CECSocket::OnLost(), so a class
+	// that multi-inherits from both (CECMuleSocket) can override the
+	// CLibSocket-side hook unambiguously and forward to the EC-layer
+	// OnLost().  Without that disambiguation, the Asio reactor's
+	// EOF-on-read dispatch lands on the empty CLibSocket::OnLost{}
+	// instead of CRemoteConnect / CECServerSocket overrides.
+	virtual void OnLost(int) {}
 	virtual void OnProxyEvent(int) {}
 
 private:
diff --git a/src/LibSocketAsio.cpp b/src/LibSocketAsio.cpp
@@ -1772,7 +1772,7 @@ namespace MuleNotify
 			socket->OnProxyEvent(MULE_SOCKET_LOST);
 		} else {
 			AddDebugLogLineF(logAsio, CFormat("LibSocketLost %s") % socket->GetIP());
-			socket->OnLost();
+			socket->OnLost(0);
 		}
 	}
 
diff --git a/src/libs/ec/cpp/ECMuleSocket.h b/src/libs/ec/cpp/ECMuleSocket.h
@@ -45,6 +45,19 @@ class CECMuleSocket : public CECSocket,  public CLibSocket {
 	virtual void OnConnect(int)	{ OnConnect(); }	// This is called from LibSocketAsio
 	virtual void OnSend(int)	{ OnOutput(); }
 	virtual void OnReceive(int)	{ OnInput(); }
+	// CLibSocket::OnLost(int) fires from the Asio reactor when the
+	// peer FIN reaches our kernel (HandleRead returning bytes=0 or
+	// an EOF error_code). Forward to the EC-layer CECSocket::OnLost()
+	// virtual so CRemoteConnect / CECServerSocket overrides actually
+	// run — without this the empty CLibSocket::OnLost(int){} default
+	// would swallow the notification and the UI would stay "connected"
+	// even after the connection died at the TCP layer.
+	//
+	// The cast to CECSocket* forces virtual dispatch through the EC
+	// vtable, so an instance of CRemoteConnect / CECServerSocket
+	// reaches its override.  A qualified `CECSocket::OnLost()` call
+	// would bypass virtual dispatch and only run the empty base.
+	virtual void OnLost(int)	{ static_cast<CECSocket *>(this)->OnLost(); }
 
 	// Apply EC-tuned TCP keepalive (idle=30s / probe=10s / count=3 →
 	// ~60s half-open detection). Called automatically from
diff --git a/src/webserver/src/WebSocket.cpp b/src/webserver/src/WebSocket.cpp
@@ -51,7 +51,7 @@ CWebSocket::CWebSocket(CWebServerBase *parent)
 
 }
 
-void CWebSocket::OnLost()
+void CWebSocket::OnLost(int)
 {
 	Close();
 	Destroy();
diff --git a/src/webserver/src/WebSocket.h b/src/webserver/src/WebSocket.h
@@ -45,7 +45,7 @@ class CWebSocket : public CLibSocket {
 
 		virtual void OnSend(int);
 		virtual void OnReceive(int);
-		virtual void OnLost();
+		virtual void OnLost(int);
 
         void OnRequestReceived(char* pHeader, char* pData, uint32 dwDataLen);
 

Original file line number	Diff line number	Diff line change
`@@ -1772,7 +1772,7 @@ namespace MuleNotify`
`1772`	`1772`	`socket->OnProxyEvent(MULE_SOCKET_LOST);`
`1773`	`1773`	`} else {`
`1774`	`1774`	`AddDebugLogLineF(logAsio, CFormat("LibSocketLost %s") % socket->GetIP());`
`1775`		`- socket->OnLost();`
	`1775`	`+ socket->OnLost(0);`
`1776`	`1776`	`}`
`1777`	`1777`	`}`
`1778`	`1778`
Original file line number	Diff line number	Diff line change
`@@ -51,7 +51,7 @@ CWebSocket::CWebSocket(CWebServerBase *parent)`
`51`	`51`
`52`	`52`	`}`
`53`	`53`
`54`		`-void CWebSocket::OnLost()`
	`54`	`+void CWebSocket::OnLost(int)`
`55`	`55`	`{`
`56`	`56`	`Close();`
`57`	`57`	`Destroy();`