From fe624a6abfc55cc3efe9ed0050a7d1c26c2a5070 Mon Sep 17 00:00:00 2001
From: Marten Seemann <martenseemann@gmail.com>
Date: Sun, 9 Jan 2022 15:29:48 +0400
Subject: [PATCH] respect the context when opening a new stream in the base
 host

---
 p2p/host/blank/blank_host.go | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/p2p/host/blank/blank_host.go b/p2p/host/blank/blank_host.go
index 09cc99e9d3..62380adefd 100644
--- a/p2p/host/blank/blank_host.go
+++ b/p2p/host/blank/blank_host.go
@@ -203,10 +203,24 @@ func (h *BaseHost) NewStream(ctx context.Context, p peer.ID, protos ...protocol.
 		return nil, err
 	}
 
-	selected, err := msmux.SelectOneOf(protocol.ConvertToStrings(protos), s)
-	if err != nil {
+	// Negotiate the protocol in the background, obeying the context.
+	var selected string
+	errCh := make(chan error, 1)
+	go func() {
+		selected, err = msmux.SelectOneOf(protocol.ConvertToStrings(protos), s)
+		errCh <- err
+	}()
+	select {
+	case err = <-errCh:
+		if err != nil {
+			s.Reset()
+			return nil, err
+		}
+	case <-ctx.Done():
 		s.Reset()
-		return nil, err
+		// wait for `SelectOneOf` to error out because of resetting the stream.
+		<-errCh
+		return nil, ctx.Err()
 	}
 
 	selpid := protocol.ID(selected)