Complete all outstanding callbacks on socket error

Author: benaadams

src/Microsoft.AspNet.Server.Kestrel/Http/SocketOutput.cs

@@ -140,6 +140,10 @@ private void ScheduleWrite()
             {
                 _thread.Post(_this => _this.WriteAllPending(), this);
             }
+            else
+            {
+                CompleteAllCallbacksWithError(_lastWriteError ?? new InvalidOperationException("Socket is closed"));
+            }
         }
 
         // This is called on the libuv event loop
@@ -177,6 +181,20 @@ private void WriteAllPending()
                 throw;
             }
         }
+        
+        private void CompleteAllCallbacksWithError(Exception error)
+        {
+            lock (_lockObj)
+            {
+                while (_callbacksPending.Count > 0)
+                {
+                    var callbackContext = _callbacksPending.Dequeue();
+
+                    // callback(error, state, calledInline)
+                    callbackContext.Callback(error, callbackContext.State, false);
+                }
+            }
+        }
 
         // This is called on the libuv event loop
         private void OnWriteCompleted(Queue<ArraySegment<byte>> writtenBuffers, int status, Exception error)