Create AsyncAutoResetEvent.cs

Author: ReferenceType

AsyncAutoResetEvent.cs

@@ -0,0 +1,62 @@
+    public class AsyncAutoResetEvent
+    {
+        private readonly static Task completed = Task.FromResult(true);
+        private readonly ConcurrentQueue<TaskCompletionSource<bool>> waiters = new ConcurrentQueue<TaskCompletionSource<bool>>();
+        private bool signaled;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AsyncAutoResetEvent"/>
+        /// class with a Boolean value indicating whether to set the initial state to signaled.
+        /// </summary>
+        /// <param name="signaled">if set to <c>true</c> [signaled].</param>
+        public AsyncAutoResetEvent(bool signaled = false)
+        {
+            this.signaled = signaled;
+        }
+
+        
+        /// <summary>
+        ///    Switches state machine of the current task until the event is signaled,
+        ///    a signal.
+        /// </summary>
+        /// <returns></returns>
+        public Task WaitAsync()
+        {
+            lock (waiters)
+            {
+                if (signaled)
+                {
+                    signaled = false;
+                    return completed;
+                }
+                else
+                {
+                    var tcs = new TaskCompletionSource<bool>();
+                    waiters.Enqueue(tcs);
+                    return tcs.Task;
+                }
+            }
+        }
+
+        /// <summary>
+        /// Sets the state of the event to signaled, allowing one or more waiting tasks to proceed.
+        /// </summary>
+        public void Set()
+        {
+            TaskCompletionSource<bool> toRelease = null;
+            lock (waiters)
+            {
+                if (waiters.Count > 0)
+                {
+                    waiters.TryDequeue(out toRelease);
+                }
+
+                else if (!signaled)
+                    signaled = true;
+
+                if (toRelease != null)
+                    toRelease.SetResult(true);
+            }
+          
+        }
+    }