From c9158cb15f8719049b2fdef728fab08ae258b6dd Mon Sep 17 00:00:00 2001
From: Kleissner <peter@kleissner.investments>
Date: Sun, 27 Feb 2022 04:11:59 +0100
Subject: [PATCH] UDT: Fix critical bugs: Virtual Connection should not block.
 Revert close channel from last commit.

---
 Transfer Virtual Connection.go | 7 ++++---
 udt/udtsocket.go               | 5 ++---
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/Transfer Virtual Connection.go b/Transfer Virtual Connection.go
index a365c07..0d8f20a 100644
--- a/Transfer Virtual Connection.go	
+++ b/Transfer Virtual Connection.go	
@@ -44,7 +44,7 @@ func newVirtualPacketConn(peer *PeerInfo, sendData func(data []byte, sequenceNum
 	v = &virtualPacketConn{
 		peer:              peer,
 		sendData:          sendData,
-		incomingData:      make(chan []byte, 100),
+		incomingData:      make(chan []byte, 512),
 		outgoingData:      make(chan []byte),
 		terminationSignal: make(chan struct{}),
 	}
@@ -67,7 +67,7 @@ func (v *virtualPacketConn) writeForward() {
 	}
 }
 
-// receiveData receives incoming data via an external message. Blocking until a read occurs or the connection is terminated!
+// receiveData receives incoming data via an external message. Non-blocking.
 func (v *virtualPacketConn) receiveData(data []byte) {
 	if v.IsTerminated() {
 		return
@@ -77,8 +77,9 @@ func (v *virtualPacketConn) receiveData(data []byte) {
 	select {
 	case v.incomingData <- data:
 	case <-v.terminationSignal:
+	default:
+		// packet lost
 	}
-	// TODO: Add read timeout
 }
 
 // Terminate closes the connection. Do not call this function manually. Use the underlying protocol's function to close the connection.
diff --git a/udt/udtsocket.go b/udt/udtsocket.go
index 5e791d2..01c3948 100644
--- a/udt/udtsocket.go
+++ b/udt/udtsocket.go
@@ -302,7 +302,6 @@ func (s *udtSocket) Close() error {
 	}
 
 	s.isClosed = true
-	close(s.sockClosed)
 
 	// closing messageOut was a signal supposed to tell the send code to initiate shutdown. However, it closes too fast before all data is transferred.
 	// The entire UDT code is a piece of !@#$ and needs a rewrite.
@@ -713,8 +712,6 @@ func (s *udtSocket) readPacket(m *multiplexer, p packet.Packet) {
 		return
 	}
 
-	s.recvEvent <- recvPktEvent{pkt: p, now: now}
-
 	switch sp := p.(type) {
 	case *packet.HandshakePacket: // sent by both peers
 		s.readHandshake(m, sp)
@@ -724,5 +721,7 @@ func (s *udtSocket) readPacket(m *multiplexer, p packet.Packet) {
 		s.sendEvent <- recvPktEvent{pkt: p, now: now}
 	case *packet.UserDefControlPacket:
 		s.cong.onCustomMsg(*sp)
+	default:
+		s.recvEvent <- recvPktEvent{pkt: p, now: now}
 	}
 }