Fixed several potential deadlocks

src/Discord.Net.Commands/CommandService.cs

@@ -62,7 +62,7 @@ namespace Discord.Commands
 								await replyChannel.SendMessage("Unable to display help: Unknown command.").ConfigureAwait(false);
 						}
                         else //Show general help							
-							await ShowGeneralHelp(e.User, e.Channel, replyChannel);
+							await ShowGeneralHelp(e.User, e.Channel, replyChannel).ConfigureAwait(false);
                     });
             }
 

src/Discord.Net/DiscordClient.cs

@@ -180,7 +180,7 @@ namespace Discord
         {
             try
             {
-                using (await _connectionLock.LockAsync())
+                using (await _connectionLock.LockAsync().ConfigureAwait(false))
                 {
                     if (State != ConnectionState.Disconnected)
                         await Disconnect().ConfigureAwait(false);
@@ -218,7 +218,7 @@ namespace Discord
             }
             catch (Exception ex)
             {
-                await _taskManager.SignalError(ex);
+                await _taskManager.SignalError(ex).ConfigureAwait(false);
                 throw;
             }
         }
@@ -268,19 +268,20 @@ namespace Discord
         }
 
         /// <summary> Disconnects from the Discord server, canceling any pending requests. </summary>
-        public async Task Disconnect()
-        {
-            if (State == ConnectionState.Connected)
-			    await ClientAPI.Send(new LogoutRequest()).ConfigureAwait(false);
-            await _taskManager.Stop(true).ConfigureAwait(false);
-        }
+        public Task Disconnect() => _taskManager.Stop(true);
 		private async Task Cleanup()
         {
+            var oldState = State;
             State = ConnectionState.Disconnecting;
+
+            if (oldState == ConnectionState.Connected)
+                await ClientAPI.Send(new LogoutRequest()).ConfigureAwait(false);
+
             if (Config.UseMessageQueue)
                 MessageQueue.Clear();
 
-            await GatewaySocket.Disconnect();
+
+            await GatewaySocket.Disconnect().ConfigureAwait(false);
             ClientAPI.Token = null;
             GatewaySocket.Token = null;
             GatewaySocket.SessionId = null;

src/Discord.Net/MessageQueue.cs

@@ -116,7 +116,7 @@ namespace Discord.Net
 
                     IQueuedAction queuedAction;
                     while (_pendingActions.TryDequeue(out queuedAction))
-                        await queuedAction.Do(this);
+                        await queuedAction.Do(this).ConfigureAwait(false);
 
                     await Task.Delay(interval).ConfigureAwait(false);
                 }

src/Discord.Net/Models/Channel.cs

@@ -366,7 +366,7 @@ namespace Discord
         public async Task<Message> SendFile(string filePath)
         { 
             using (var stream = File.OpenRead(filePath))
-                return await SendFile(Path.GetFileName(filePath), stream);
+                return await SendFile(Path.GetFileName(filePath), stream).ConfigureAwait(false);
         }
         public async Task<Message> SendFile(string filename, Stream stream)
         {

src/Discord.Net/Net/Rest/BuiltInEngine.cs

@@ -58,7 +58,7 @@ namespace Discord.Net.Rest
             {
                 if (json != null)
                     request.Content = new StringContent(json, Encoding.UTF8, "application/json");
-                return await Send(request, cancelToken);
+                return await Send(request, cancelToken).ConfigureAwait(false);
             }
         }
 		public async Task<string> SendFile(string method, string path, string filename, Stream stream, CancellationToken cancelToken)
@@ -68,7 +68,7 @@ namespace Discord.Net.Rest
                 var content = new MultipartFormDataContent("Upload----" + DateTime.Now.ToString(CultureInfo.InvariantCulture));
                 content.Add(new StreamContent(File.OpenRead(path)), "file", filename);
                 request.Content = content;
-                return await Send(request, cancelToken);
+                return await Send(request, cancelToken).ConfigureAwait(false);
             }
         }
 		private async Task<string> Send(HttpRequestMessage request, CancellationToken cancelToken)
@@ -103,7 +103,7 @@ namespace Discord.Net.Rest
                         var now = DateTime.UtcNow;
                         if (now >= _rateLimitTime)
                         {
-                            using (await _rateLimitLock.LockAsync())
+                            using (await _rateLimitLock.LockAsync().ConfigureAwait(false))
                             {
                                 if (now >= _rateLimitTime)
                                 {
@@ -120,7 +120,7 @@ namespace Discord.Net.Rest
                 else if (statusCode < 200 || statusCode >= 300) //2xx = Success
                     throw new HttpException(response.StatusCode);
                 else
-                    return await response.Content.ReadAsStringAsync();
+                    return await response.Content.ReadAsStringAsync().ConfigureAwait(false);
             }
 		}
 

src/Discord.Net/Net/Rest/RestClient.cs

@@ -130,7 +130,7 @@ namespace Discord.Net.Rest
             if (request == null) throw new ArgumentNullException(nameof(request));
 
             OnSendingRequest(request);
-            var results = await SendFile(request, false);
+            var results = await SendFile(request, false).ConfigureAwait(false);
             OnSentRequest(request, null, null, results.Milliseconds);
         }
 

src/Discord.Net/Net/Rest/SharpRestEngine.cs

@@ -92,7 +92,7 @@ namespace Discord.Net.Rest
                         var now = DateTime.UtcNow;
                         if (now >= _rateLimitTime)
                         {
-                            using (await _rateLimitLock.LockAsync())
+                            using (await _rateLimitLock.LockAsync().ConfigureAwait(false))
                             {
                                 if (now >= _rateLimitTime)
                                 {

src/Discord.Net/Net/WebSockets/WS4NetEngine.cs

@@ -88,7 +88,7 @@ namespace Discord.Net.WebSockets
 
         private async void OnWebSocketError(object sender, ErrorEventArgs e)
         {
-            await _taskManager.SignalError(e.Exception);
+            await _taskManager.SignalError(e.Exception).ConfigureAwait(false);
             _waitUntilConnect.Set();
             _waitUntilDisconnect.Set();
         }
@@ -99,7 +99,7 @@ namespace Discord.Net.WebSockets
                 ex = new WebSocketException((e as ClosedEventArgs).Code, (e as ClosedEventArgs).Reason);
             else
                 ex = new Exception("Connection lost");
-            await _taskManager.SignalError(ex);
+            await _taskManager.SignalError(ex).ConfigureAwait(false);
             _waitUntilConnect.Set();
             _waitUntilDisconnect.Set();
         }

src/Discord.Net/Net/WebSockets/WebSocket.cs

@@ -73,7 +73,7 @@ namespace Discord.Net.WebSockets
 		{
             try
             {
-                using (await _lock.LockAsync())
+                using (await _lock.LockAsync().ConfigureAwait(false))
                 {
                     await _taskManager.Stop().ConfigureAwait(false);
                     _taskManager.ClearException();
@@ -90,7 +90,7 @@ namespace Discord.Net.WebSockets
 			catch (Exception ex)
 			{
                 //TODO: Should this be inside the lock?
-                await _taskManager.SignalError(ex);
+                await _taskManager.SignalError(ex).ConfigureAwait(false);
                 throw;
 			}
 		}
@@ -106,7 +106,7 @@ namespace Discord.Net.WebSockets
 			}
 			catch (Exception ex)
             {
-                await _taskManager.SignalError(ex);
+                await _taskManager.SignalError(ex).ConfigureAwait(false);
             }
 		}
 

src/Discord.Net/TaskManager.cs

@@ -46,7 +46,7 @@ namespace Discord
                 if (task != null)
                     await Stop().ConfigureAwait(false);
 
-                using (await _lock.LockAsync())
+                using (await _lock.LockAsync().ConfigureAwait(false))
                 {
                     _cancelSource = cancelSource;
 
@@ -67,14 +67,14 @@ namespace Discord
 
                         //Signal the rest of the tasks to stop
                         if (firstTask.Exception != null)
-                            await SignalError(firstTask.Exception);
+                            await SignalError(firstTask.Exception).ConfigureAwait(false);
                         else
-                            await SignalStop();
+                            await SignalStop().ConfigureAwait(false);
 
                         //Wait for the other tasks, and signal their errors too just in case
                         try { await allTasks.ConfigureAwait(false); }
-                        catch (AggregateException ex) { await SignalError(ex.InnerExceptions.First()); } 
-                        catch (Exception ex) { await SignalError(ex); }
+                        catch (AggregateException ex) { await SignalError(ex.InnerExceptions.First()).ConfigureAwait(false); } 
+                        catch (Exception ex) { await SignalError(ex).ConfigureAwait(false); }
 
                         //Run the cleanup function within our lock
                         if (_stopAction != null)
@@ -89,7 +89,7 @@ namespace Discord
 
         public async Task SignalStop(bool isExpected = false)
         {
-            using (await _lock.LockAsync())
+            using (await _lock.LockAsync().ConfigureAwait(false))
             {
                 if (isExpected)
                     _wasStopExpected = true;
@@ -104,7 +104,7 @@ namespace Discord
         public async Task Stop(bool isExpected = false)
         {
             Task task;
-            using (await _lock.LockAsync())
+            using (await _lock.LockAsync().ConfigureAwait(false))
             {
                 if (isExpected)
                     _wasStopExpected = true;
@@ -116,12 +116,12 @@ namespace Discord
                 if (!_cancelSource.IsCancellationRequested && _cancelSource != null)
                     _cancelSource.Cancel();
             }
-            await task;
+            await task.ConfigureAwait(false);
         }
 
         public async Task SignalError(Exception ex)
         {
-            using (await _lock.LockAsync())
+            using (await _lock.LockAsync().ConfigureAwait(false))
             {
                 if (_stopReason != null) return;
 
@@ -133,7 +133,7 @@ namespace Discord
         public async Task Error(Exception ex)
         {
             Task task;
-            using (await _lock.LockAsync())
+            using (await _lock.LockAsync().ConfigureAwait(false))
             {
                 if (_stopReason != null) return;
 
@@ -146,7 +146,7 @@ namespace Discord
                         _cancelSource.Cancel();
                 }
             }
-            await task;
+            await task.ConfigureAwait(false);
         }
 
         /// <summary> Throws an exception if one was captured. </summary>