From 69f55f34aacbc9979a6c4b88190f3d7e6b7fa968 Mon Sep 17 00:00:00 2001
From: Benjamin Hallion <bhallion@ohbibi.com>
Date: Thu, 25 May 2023 12:34:29 +0200
Subject: [PATCH] read.go: Avoid handling ping after close frame has been sent

Closes #298
---
 read.go | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/read.go b/read.go
index 6d0e9aa9..d7facb31 100644
--- a/read.go
+++ b/read.go
@@ -286,6 +286,13 @@ func (c *Conn) handleControl(ctx context.Context, h header) (err error) {
 
 	switch h.opcode {
 	case opPing:
+		c.closeMu.Lock()
+		wroteClose := c.wroteClose
+		c.closeMu.Unlock()
+		if wroteClose {
+			// Cannot respond to ping with a pong because we already sent a close frame.
+			return nil
+		}
 		return c.writeControl(ctx, opPong, b)
 	case opPong:
 		c.activePingsMu.Lock()