From 9de4e88ca652f5727b22201b79e705853b60ee33 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jo=C3=A3o=20Oliveirinha?= <joliveirinha@cloudflare.com>
Date: Wed, 10 Aug 2022 14:21:55 +0100
Subject: [PATCH] TUN-6646: Add support to SafeStreamCloser to close only write
 side of stream

---
 quic/safe_stream.go | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/quic/safe_stream.go b/quic/safe_stream.go
index 12ba76f4..c151ff2e 100644
--- a/quic/safe_stream.go
+++ b/quic/safe_stream.go
@@ -41,3 +41,14 @@ func (s *SafeStreamCloser) Close() error {
 	s.stream.CancelRead(0)
 	return s.stream.Close()
 }
+
+func (s *SafeStreamCloser) CloseWrite() error {
+	s.lock.Lock()
+	defer s.lock.Unlock()
+
+	// As documented by the quic-go library, this doesn't actually close the entire stream.
+	// It prevents further writes, which in turn will result in an EOF signal being sent the other side of stream when
+	// reading.
+	// We can still read from this stream.
+	return s.stream.Close()
+}