From 7410ce9077e0be81b29fd40f6a3cbf784a0238ae Mon Sep 17 00:00:00 2001
From: Minecrell <minecrell@minecrell.net>
Date: Mon, 9 Jul 2018 01:57:21 +0200
Subject: [PATCH] #2449: Avoid stopping if already in progress

Currently it is possible to stop the proxy multiple times, causing
the shutdown routines to be called twice. This doesn't make any
sense and may even cause problems with some plugins.

Cancel early if stopping is already in progress to avoid this.
---
 proxy/src/main/java/net/md_5/bungee/BungeeCord.java | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/proxy/src/main/java/net/md_5/bungee/BungeeCord.java b/proxy/src/main/java/net/md_5/bungee/BungeeCord.java
index d0b987361..fd4c2bf91 100644
--- a/proxy/src/main/java/net/md_5/bungee/BungeeCord.java
+++ b/proxy/src/main/java/net/md_5/bungee/BungeeCord.java
@@ -379,8 +379,14 @@ public class BungeeCord extends ProxyServer
     }
 
     @Override
-    public void stop(final String reason)
+    public synchronized void stop(final String reason)
     {
+        if ( !isRunning )
+        {
+            return;
+        }
+        isRunning = false;
+
         new Thread( "Shutdown Thread" )
         {
             @Override
@@ -388,8 +394,6 @@ public class BungeeCord extends ProxyServer
             @SuppressWarnings("TooBroadCatch")
             public void run()
             {
-                BungeeCord.this.isRunning = false;
-
                 stopListeners();
                 getLogger().info( "Closing pending connections" );