From 2aeacadefd89a4b6dcae67dfaf99d560603da9ac Mon Sep 17 00:00:00 2001
From: Richard Schneider <makaretu@gmail.com>
Date: Wed, 7 Mar 2018 22:59:06 +1300
Subject: [PATCH] fix: more thread safety

---
 src/MulticastService.cs | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/src/MulticastService.cs b/src/MulticastService.cs
index 7d0f72e..d6872b8 100644
--- a/src/MulticastService.cs
+++ b/src/MulticastService.cs
@@ -198,10 +198,15 @@ void FindNetworkInterfaces(object state)
             // Tell others.
             if (nics.Length > 0)
             {
-                NetworkInterfaceDiscovered?.Invoke(this, new NetworkInterfaceEventArgs
+                lock (socketLock)
                 {
-                    NetworkInterfaces = nics
-                });
+                    if (socket == null || nicTimer == null)
+                        return;
+                    NetworkInterfaceDiscovered?.Invoke(this, new NetworkInterfaceEventArgs
+                    {
+                        NetworkInterfaces = nics
+                    });
+                }
             }
         }