UI: LoadGuestApplication asynchronous cancellation (#1)

Fixed LoadGuestApplication hanging when cancelled.
Since startup procedure has technically changed, we should consider testing this with a variety of game formats to ensure regressions do not occur.
Closes [#20](https://github.com/Ryubing/Issues/issues/20)

Reviewed-on: https://git.ryujinx.app/projects/Ryubing/pulls/1

src/Ryujinx.Graphics.Vulkan/Auto.cs

@@ -1,3 +1,4 @@
+using Ryujinx.Common.Logging;
 using System;
 using System.Diagnostics;
 using System.Threading;
@@ -114,7 +115,7 @@ namespace Ryujinx.Graphics.Vulkan
                 cbs.AddDependant(this);
 
                 // We need to add a dependency on the command buffer to all objects this object
-                // references aswell.
+                // references as well.
                 if (_referencedObjs != null)
                 {
                     for (int i = 0; i < _referencedObjs.Length; i++)
@@ -176,6 +177,8 @@ namespace Ryujinx.Graphics.Vulkan
                 }
             }
 
+            // This can somehow become -1.
+            // Logger.Info?.PrintMsg(LogClass.Gpu, $"_referenceCount: {_referenceCount}");
             Debug.Assert(_referenceCount >= 0);
         }
 

src/Ryujinx.HLE/Loaders/Processes/ProcessLoader.cs

@@ -14,6 +14,7 @@ using Ryujinx.HLE.Loaders.Executables;
 using Ryujinx.HLE.Loaders.Processes.Extensions;
 using System;
 using System.Collections.Concurrent;
+using System.Collections.Generic;
 using System.IO;
 using Path = System.IO.Path;
 
@@ -27,10 +28,15 @@ namespace Ryujinx.HLE.Loaders.Processes
 
         private ulong _latestPid;
 
-        public ProcessResult ActiveApplication
+        public ProcessResult? ActiveApplication
         {
             get
             {
+                return _processesByPid.GetValueOrDefault(_latestPid);
+                
+                // Using this if statement locks up the UI and prevents a new game from loading.
+                // Haven't quite deduced why yet.
+                
                 if (!_processesByPid.TryGetValue(_latestPid, out ProcessResult value))
                     throw new RyujinxException(
                         $"The HLE Process map did not have a process with ID {_latestPid}. Are you missing firmware?");

src/Ryujinx.HLE/Loaders/Processes/ProcessResult.cs

@@ -4,7 +4,6 @@ using LibHac.Ns;
 using Ryujinx.Common.Logging;
 using Ryujinx.Cpu;
 using Ryujinx.HLE.HOS.SystemState;
-using Ryujinx.HLE.Loaders.Processes.Extensions;
 using Ryujinx.Horizon.Common;
 
 namespace Ryujinx.HLE.Loaders.Processes
@@ -52,6 +51,7 @@ namespace Ryujinx.HLE.Loaders.Processes
 
             if (metaLoader is not null)
             {
+                Logger.Info?.Print(LogClass.Application,$"metaLoader: {metaLoader}");
                 ulong programId = metaLoader.ProgramId;
 
                 Name = ApplicationControlProperties.Title[(int)titleLanguage].NameString.ToString();
@@ -73,6 +73,13 @@ namespace Ryujinx.HLE.Loaders.Processes
                 Is64Bit = metaLoader.IsProgram64Bit;
             } 
             
+            else
+            {
+                Logger.Error?.Print(LogClass.Application,$"metaLoader is null !!!");
+                ProcessId = 0;
+                return;
+            }
+            
             DiskCacheEnabled = diskCacheEnabled;
             AllowCodeMemoryForJit = allowCodeMemoryForJit;
         }

src/Ryujinx/Systems/AppHost.cs

@@ -62,7 +62,7 @@ using VSyncMode = Ryujinx.Common.Configuration.VSyncMode;
 
 namespace Ryujinx.Ava.Systems
 {
-    internal class AppHost
+    internal class AppHost : IDisposable
     {
         private const int CursorHideIdleTime = 5; // Hide Cursor seconds.
         private const float MaxResolutionScale = 4.0f; // Max resolution hotkeys can scale to before wrapping.
@@ -438,7 +438,7 @@ namespace Ryujinx.Ava.Systems
 
                         SaveBitmapAsPng(bitmapToSave, path);
 
-                        Logger.Notice.Print(LogClass.Application, $"Screenshot saved to {path}", "Screenshot");
+                        Logger.Notice.Print(LogClass.Application, $"Screenshot saved to '{path}'.", "Screenshot");
                     }
                 });
             }
@@ -611,26 +611,39 @@ namespace Ryujinx.Ava.Systems
 
             _isActive = false;
 
-            // NOTE: The render loop is allowed to stay alive until the renderer itself is disposed, as it may handle resource dispose.
-            // We only need to wait for all commands submitted during the main gpu loop to be processed.
-            _gpuDoneEvent.WaitOne();
-            _gpuDoneEvent.Dispose();
-
             DisplaySleep.Restore();
 
             NpadManager.Dispose();
             TouchScreenManager.Dispose();
             Device.Dispose();
             
-            DisposeGpu();
+            // NOTE: The render loop is allowed to stay alive until the renderer itself is disposed, as it may handle resource dispose.
+            // We only need to wait for all commands submitted during the main gpu loop to be processed.
+            // If the GPU has no work and is cancelled, we need to handle that as well.
 
+            WaitHandle.WaitAny(new[] { _gpuDoneEvent, _gpuCancellationTokenSource.Token.WaitHandle });
+            _gpuCancellationTokenSource.Dispose();
+            
+            // Waiting for work to be finished before we dispose.
+            if (_renderingStarted)
+            {
+                Device.Gpu.WaitUntilGpuReady();
+            }
+            
+            _gpuDoneEvent.Dispose();
+            
+            DisposeGpu();
             AppExit?.Invoke(this, EventArgs.Empty);
         }
 
-        private void Dispose()
+        // MUST be public to inherit from IDisposable
+        public void Dispose()
         {
             if (Device.Processes != null)
-                MainWindowViewModel.UpdateGameMetadata(Device.Processes.ActiveApplication.ProgramIdText, _playTimer.Elapsed);
+            {
+                MainWindowViewModel.UpdateGameMetadata(Device.Processes.ActiveApplication?.ProgramIdText, 
+                    _playTimer.Elapsed);
+            }
             
             ConfigurationState.Instance.System.IgnoreMissingServices.Event -= UpdateIgnoreMissingServicesState;
             ConfigurationState.Instance.Graphics.AspectRatio.Event -= UpdateAspectRatioState;
@@ -646,7 +659,6 @@ namespace Ryujinx.Ava.Systems
             _topLevel.PointerExited -= TopLevel_PointerExited;
 
             _gpuCancellationTokenSource.Cancel();
-            _gpuCancellationTokenSource.Dispose();
 
             _chrono.Stop();
             _playTimer.Stop();
@@ -672,6 +684,12 @@ namespace Ryujinx.Ava.Systems
             }
             else
             {
+                // No use waiting on something that never started work
+                if (_renderingStarted)
+                {
+                    Device.Gpu.WaitUntilGpuReady();
+                }
+                
                 Device.DisposeGpu();
             }
         }
@@ -686,7 +704,7 @@ namespace Ryujinx.Ava.Systems
             _cursorState = CursorStates.ForceChangeCursor;
         }
 
-        public async Task<bool> LoadGuestApplication(BlitStruct<ApplicationControlProperty>? customNacpData = null)
+        public async Task LoadGuestApplication(CancellationTokenSource cts, BlitStruct<ApplicationControlProperty>? customNacpData = null)
         {
             DiscordIntegrationModule.GuestAppStartedAt = Timestamps.Now;
 
@@ -715,7 +733,8 @@ namespace Ryujinx.Ava.Systems
                                 await UserErrorDialog.ShowUserErrorDialog(userError);
                                 Device.Dispose();
 
-                                return false;
+                                cts.Cancel();
+                                throw new OperationCanceledException(cts.Token);
                             }
                         }
 
@@ -724,10 +743,11 @@ namespace Ryujinx.Ava.Systems
                             await UserErrorDialog.ShowUserErrorDialog(userError);
                             Device.Dispose();
 
-                            return false;
+                            cts.Cancel();
+                            throw new OperationCanceledException(cts.Token);
                         }
 
-                        // Tell the user that we installed a firmware for them.
+                        // Tell the user that we installed firmware for them.
                         if (userError is UserError.NoFirmware)
                         {
                             firmwareVersion = ContentManager.GetCurrentFirmwareVersion();
@@ -747,7 +767,8 @@ namespace Ryujinx.Ava.Systems
                         await UserErrorDialog.ShowUserErrorDialog(userError);
                         Device.Dispose();
 
-                        return false;
+                        cts.Cancel();
+                        throw new OperationCanceledException(cts.Token);
                     }
                 }
             }
@@ -762,7 +783,8 @@ namespace Ryujinx.Ava.Systems
                 {
                     Device.Dispose();
 
-                    return false;
+                    cts.Cancel();
+                    throw new OperationCanceledException(cts.Token);
                 }
             }
             else if (Directory.Exists(ApplicationPath))
@@ -782,20 +804,24 @@ namespace Ryujinx.Ava.Systems
 
                     if (!Device.LoadCart(ApplicationPath, romFsFiles[0]))
                     {
+                        await ContentDialogHelper.CreateErrorDialog(
+                            "Please specify an unpacked game directory with a valid exefs or NSO/NRO.");
                         Device.Dispose();
 
-                        return false;
+                        cts.Cancel();
+                        throw new OperationCanceledException(cts.Token);
                     }
                 }
                 else
                 {
                     Logger.Info?.Print(LogClass.Application, "Loading as cart WITHOUT RomFS.");
-
                     if (!Device.LoadCart(ApplicationPath))
                     {
+                        await ContentDialogHelper.CreateErrorDialog(
+                            "Please specify an unpacked game directory with a valid exefs or NSO/NRO.");
                         Device.Dispose();
-
+                        cts.Cancel();
-                        return false;
+                        throw new OperationCanceledException(cts.Token);
                     }
                 }
             }
@@ -813,7 +839,8 @@ namespace Ryujinx.Ava.Systems
                             {
                                 Device.Dispose();
 
-                                return false;
+                                cts.Cancel();
+                                throw new OperationCanceledException(cts.Token);
                             }
 
                             break;
@@ -826,7 +853,8 @@ namespace Ryujinx.Ava.Systems
                             {
                                 Device.Dispose();
 
-                                return false;
+                                cts.Cancel();
+                                throw new OperationCanceledException(cts.Token);
                             }
 
                             break;
@@ -840,7 +868,8 @@ namespace Ryujinx.Ava.Systems
                             {
                                 Device.Dispose();
 
-                                return false;
+                                cts.Cancel();
+                                throw new OperationCanceledException(cts.Token);
                             }
 
                             break;
@@ -855,7 +884,8 @@ namespace Ryujinx.Ava.Systems
                                 {
                                     Device.Dispose();
 
-                                    return false;
+                                    cts.Cancel();
+                                    throw new OperationCanceledException(cts.Token);
                                 }
                             }
                             catch (ArgumentOutOfRangeException)
@@ -864,7 +894,8 @@ namespace Ryujinx.Ava.Systems
 
                                 Device.Dispose();
 
-                                return false;
+                                cts.Cancel();
+                                throw new OperationCanceledException(cts.Token);
                             }
 
                             break;
@@ -873,19 +904,18 @@ namespace Ryujinx.Ava.Systems
             }
             else
             {
-                Logger.Warning?.Print(LogClass.Application, "Please specify a valid XCI/NCA/NSP/PFS0/NRO file.");
+                Logger.Warning?.Print(LogClass.Application, "Please specify a valid XCI/NCA/NSP/PFS0/NSO/NRO file.");
 
                 Device.Dispose();
 
-                return false;
+                cts.Cancel();
+                throw new OperationCanceledException(cts.Token);
             }
 
             ApplicationLibrary.LoadAndSaveMetaData(Device.Processes.ActiveApplication.ProgramIdText,
                 appMetadata => appMetadata.UpdatePreGame()
             );
             _playTimer.Start();
-
-            return true;
         }
 
         internal void Resume()
@@ -895,7 +925,7 @@ namespace Ryujinx.Ava.Systems
             _viewModel.IsPaused = false;
             _playTimer.Start();
             _viewModel.Title = TitleHelper.ActiveApplicationTitle(Device?.Processes.ActiveApplication, Program.Version, !ConfigurationState.Instance.ShowOldUI);
-            Logger.Info?.Print(LogClass.Emulation, "Emulation was resumed");
+            Logger.Info?.Print(LogClass.Emulation, "Emulation was resumed.");
         }
 
         internal void Pause()
@@ -905,7 +935,7 @@ namespace Ryujinx.Ava.Systems
             _viewModel.IsPaused = true;
             _playTimer.Stop();
             _viewModel.Title = TitleHelper.ActiveApplicationTitle(Device?.Processes.ActiveApplication, Program.Version, !ConfigurationState.Instance.ShowOldUI, LocaleManager.Instance[LocaleKeys.Paused]);
-            Logger.Info?.Print(LogClass.Emulation, "Emulation was paused");
+            Logger.Info?.Print(LogClass.Emulation, "Emulation was paused.");
         }
 
         private void InitEmulatedSwitch()
@@ -1104,7 +1134,9 @@ namespace Ryujinx.Ava.Systems
                 // Make sure all commands in the run loop are fully executed before leaving the loop.
                 if (Device.Gpu.Renderer is ThreadedRenderer threaded)
                 {
+                    Logger.Info?.PrintMsg(LogClass.Gpu, "Flushing threaded commands...");
                     threaded.FlushThreadedCommands();
+                    Logger.Info?.PrintMsg(LogClass.Gpu, "Flushed!");
                 }
 
                 _gpuDoneEvent.Set();

src/Ryujinx/Systems/AppLibrary/ApplicationLibrary.cs

@@ -849,7 +849,8 @@ namespace Ryujinx.Ava.Systems.AppLibrary
 
             foreach (ApplicationData installedApplication in Applications.Items)
             {
-                temporary += LoadAndSaveMetaData(installedApplication.IdString).TimePlayed;
+                // this should always exist... should...
+                temporary += LoadAndSaveMetaData(installedApplication.IdString).Value.TimePlayed;
             }
 
             TotalTimePlayed = temporary;
@@ -1159,8 +1160,14 @@ namespace Ryujinx.Ava.Systems.AppLibrary
             ApplicationCountUpdated?.Invoke(null, e);
         }
 
-        public static ApplicationMetadata LoadAndSaveMetaData(string titleId, Action<ApplicationMetadata> modifyFunction = null)
+        public static Gommon.Optional<ApplicationMetadata> LoadAndSaveMetaData(string titleId, Action<ApplicationMetadata> modifyFunction = null)
         {
+            if (titleId is null)
+            {
+                Logger.Warning?.PrintMsg(LogClass.Application, "Cannot save metadata because title ID is invalid.");
+                return null;
+            }
+            
             string metadataFolder = Path.Combine(AppDataManager.GamesDirPath, titleId, "gui");
             string metadataFile = Path.Combine(metadataFolder, "metadata.json");
 
@@ -1168,6 +1175,7 @@ namespace Ryujinx.Ava.Systems.AppLibrary
             
             if (!File.Exists(metadataFile))
             {
+                Logger.Info?.Print(LogClass.Application, $"Metadata file does not exist. Creating metadata for {titleId}...");
                 Directory.CreateDirectory(metadataFolder);
 
                 appMetadata = new ApplicationMetadata();
@@ -1177,12 +1185,12 @@ namespace Ryujinx.Ava.Systems.AppLibrary
 
             try
             {
+                Logger.Debug?.Print(LogClass.Application, $"Deserializing metadata for {titleId}...");
                 appMetadata = JsonHelper.DeserializeFromFile(metadataFile, _serializerContext.ApplicationMetadata);
             }
             catch (JsonException)
             {
                 Logger.Warning?.Print(LogClass.Application, $"Failed to parse metadata json for {titleId}. Loading defaults.");
-
                 appMetadata = new ApplicationMetadata();
             }
 

src/Ryujinx/Systems/DiscordIntegrationModule.cs

@@ -82,7 +82,7 @@ namespace Ryujinx.Ava.Systems
 
         public static void Use(Optional<string> titleId)
         {
-            if (titleId.TryGet(out string tid))
+            if (titleId.TryGet(out string tid) && Switch.Shared.Processes.ActiveApplication is not null)
                 SwitchToPlayingState(
                     ApplicationLibrary.LoadAndSaveMetaData(tid),
                     Switch.Shared.Processes.ActiveApplication

src/Ryujinx/UI/Models/SaveModel.cs

@@ -57,8 +57,15 @@ namespace Ryujinx.Ava.UI.Models
             }
             else
             {
-                ApplicationMetadata appMetadata = ApplicationLibrary.LoadAndSaveMetaData(TitleIdString);
+                Gommon.Optional<ApplicationMetadata> appMetadata = ApplicationLibrary.LoadAndSaveMetaData(TitleIdString);
-                Title = appMetadata.Title ?? TitleIdString;
+                if (appMetadata != null)
+                {
+                    Title = appMetadata.Value.Title ?? TitleIdString;
+                }
+                else
+                {
+                    Title = "<INVALID>";
+                }
             }
 
             Task.Run(() =>

src/Ryujinx/UI/ViewModels/MainWindowViewModel.cs

@@ -1760,11 +1760,6 @@ namespace Ryujinx.Ava.UI.ViewModels
 
             Logger.RestartTime();
 
-            SelectedIcon ??= ApplicationLibrary.GetApplicationIcon(application.Path,
-                ConfigurationState.Instance.System.Language, application.Id);
-
-            PrepareLoadScreen();
-
             RendererHostControl = new RendererHost();
 
             AppHost = new AppHost(
@@ -1779,18 +1774,34 @@ namespace Ryujinx.Ava.UI.ViewModels
                 this,
                 TopLevel);
             
-            if (!await AppHost.LoadGuestApplication(customNacpData))
+            CancellationTokenSource cts = new CancellationTokenSource();
+
+            try
             {
+                await AppHost.LoadGuestApplication(cts, customNacpData);
+            }
+            catch (OperationCanceledException exception)
+            {
+                Logger.Info?.Print(LogClass.Application,
+                    "LoadGuestApplication was interrupted !!! " + exception.Message);
                 AppHost.DisposeContext();
                 AppHost = null;
-
                 return;
             }
+            finally
+            {
+                cts.Dispose();
+            }
             
             CanUpdate = false;
 
             application.Name ??= AppHost.Device.Processes.ActiveApplication.Name;
             
+            SelectedIcon ??= ApplicationLibrary.GetApplicationIcon(application.Path,
+                ConfigurationState.Instance.System.Language, application.Id);
+
+            PrepareLoadScreen();
+
             LoadHeading = LocaleManager.Instance.UpdateAndGetDynamicValue(LocaleKeys.LoadingHeading, application.Name);
 
             SwitchToRenderer(startFullscreen);