From ed250c16b98fe3f69f7ed55e51652fb64242c73a Mon Sep 17 00:00:00 2001
From: Rolf Kristensen <sweaty1@hotmail.com>
Date: Wed, 22 May 2019 17:42:08 +0200
Subject: [PATCH] ConcurrentRequestQueue - Fixed deadlock caused by
 misunderstanding Monitor.Wait with timeout

---
 .../Targets/Wrappers/ConcurrentRequestQueue.cs   | 16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

diff --git a/src/NLog/Targets/Wrappers/ConcurrentRequestQueue.cs b/src/NLog/Targets/Wrappers/ConcurrentRequestQueue.cs
index 2869f97118..ddce926832 100644
--- a/src/NLog/Targets/Wrappers/ConcurrentRequestQueue.cs
+++ b/src/NLog/Targets/Wrappers/ConcurrentRequestQueue.cs
@@ -127,21 +127,13 @@ private long WaitForBelowRequestLimit()
                 // If yield did not help, then wait on a lock
                 while (currentCount > RequestLimit)
                 {
+                    InternalLogger.Debug("Blocking because the overflow action is Block...");
                     if (!lockTaken)
-                    {
-                        InternalLogger.Debug("Blocking because the overflow action is Block...");
                         Monitor.Enter(_logEventInfoQueue);
-                        lockTaken = true;
-                        InternalLogger.Trace("Entered critical section.");
-                    }
                     else
-                    {
-                        InternalLogger.Debug("Blocking because the overflow action is Block...");
-                        if (!Monitor.Wait(_logEventInfoQueue, 100))
-                            lockTaken = false;
-                        else
-                            InternalLogger.Trace("Entered critical section.");
-                    }
+                        Monitor.Wait(_logEventInfoQueue);
+                    lockTaken = true;
+                    InternalLogger.Trace("Entered critical section.");
                     currentCount = Interlocked.Read(ref _count);
                 }