From abc83a9190e7cce1b02e23d778c062240d66d19d Mon Sep 17 00:00:00 2001
From: Qian Wang <cbeuw.andy@gmail.com>
Date: Fri, 9 Aug 2019 10:36:27 +0100
Subject: [PATCH] Potential fix to an edge case nil pointer

---
 internal/multiplex/switchboard.go | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/internal/multiplex/switchboard.go b/internal/multiplex/switchboard.go
index 270b4ac..a67e3d2 100644
--- a/internal/multiplex/switchboard.go
+++ b/internal/multiplex/switchboard.go
@@ -76,8 +76,12 @@ func (sb *switchboard) send(data []byte, connId *uint32) (int, error) {
 			return 0, errBrokenSwitchboard
 		}
 		newConnId := rand.Intn(len(sb.conns))
-		conn = sb.conns[uint32(newConnId)]
-		return conn.Write(data)
+		conn, ok = sb.conns[uint32(newConnId)]
+		if !ok {
+			return 0, errBrokenSwitchboard
+		} else {
+			return conn.Write(data)
+		}
 	}
 
 }