From 2967b142fe110f6c01b520a67827f57e9eb1025e Mon Sep 17 00:00:00 2001
From: Yilun <zyl.skysniper@gmail.com>
Date: Mon, 3 Aug 2020 01:38:56 -0700
Subject: [PATCH] Add conn closed error to prevent closed conn hanging forever

Signed-off-by: Yilun <zyl.skysniper@gmail.com>
---
 connection.go | 6 ++++++
 errors.go     | 1 +
 2 files changed, 7 insertions(+)

diff --git a/connection.go b/connection.go
index bcc5c1c..d0e9909 100644
--- a/connection.go
+++ b/connection.go
@@ -159,6 +159,9 @@ func (conn *Connection) tx() error {
 			if conn.session.IsClosed() {
 				return ErrSessionClosed
 			}
+			if err == ErrConnClosed {
+				return err
+			}
 			log.Println(err)
 			select {
 			case conn.session.resendChan <- seq:
@@ -234,6 +237,9 @@ func (conn *Connection) sendAck() error {
 
 		err = conn.session.sendWith(conn.localClientID, conn.remoteClientID, buf, conn.retransmissionTimeout)
 		if err != nil {
+			if err == ErrConnClosed {
+				return err
+			}
 			log.Println(err)
 			time.Sleep(time.Second)
 			continue
diff --git a/errors.go b/errors.go
index 916b48f..f2960c0 100644
--- a/errors.go
+++ b/errors.go
@@ -11,6 +11,7 @@ var (
 	ErrInvalidPacket         = NewGenericError("invalid packet", false, true)
 	ErrRecvWindowFull        = NewGenericError("receive window full", false, true)
 	ErrNotHandshake          = NewGenericError("first packet is not handshake packet", false, true)
+	ErrConnClosed            = NewGenericError("connection closed", false, false)
 )
 
 type GenericError struct {