From 27e41c4ad57a9242f15c66c48cd531fa87281487 Mon Sep 17 00:00:00 2001
From: Dominic Wong <dom@micro.mu>
Date: Wed, 27 May 2020 20:18:26 +0100
Subject: [PATCH] fix locking of socket pool

---
 util/socket/pool.go | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/util/socket/pool.go b/util/socket/pool.go
index 9439f131..8ee2afb4 100644
--- a/util/socket/pool.go
+++ b/util/socket/pool.go
@@ -19,12 +19,18 @@ func (p *Pool) Get(id string) (*Socket, bool) {
 	}
 	p.RUnlock()
 
-	// create new socket
-	socket = New(id)
 	// save socket
 	p.Lock()
+	defer p.Unlock()
+	// double checked locking
+	socket, ok = p.pool[id]
+	if ok {
+		return socket, ok
+	}
+	// create new socket
+	socket = New(id)
 	p.pool[id] = socket
-	p.Unlock()
+
 	// return socket
 	return socket, false
 }