Stop tools before rebooting. Fixes crash if a Lua script's exit handler did a memory read or write.

Author: SuuperW

src/BizHawk.Client.Common/tools/Interfaces/IToolForm.cs

@@ -27,6 +27,12 @@ public interface IToolForm
 		/// </summary>
 		void UpdateValues(ToolFormUpdateType type);
 
+		/// <summary>
+		/// Stop the tool, in preparation for a game or core change.
+		/// A tool should expect that either <see cref="Restart"/> or <see cref="Close"/> will be called after this.
+		/// </summary>
+		void Stop();
+
 		/// <summary>
 		/// Will be called anytime the dialog needs to be restarted, such as when a new ROM is loaded
 		/// The tool implementing this needs to account for a Game and Core change

src/BizHawk.Client.EmuHawk/MainForm.cs

@@ -3936,6 +3936,8 @@ private bool CloseGame(bool clearSram = false)
 				if (saveMovieResult == TryAgainResult.Canceled) return false;
 			}
 
+			Tools.Stop();
+
 			if (clearSram)
 			{
 				var path = Config.PathEntries.SaveRamAbsolutePath(Game, MovieSession.Movie);

src/BizHawk.Client.EmuHawk/tools/BasicBot/BasicBot.cs

@@ -260,6 +260,18 @@ public string FromSlot
 		protected override void UpdateAfter() => Update(fast: false);
 		protected override void FastUpdateAfter() => Update(fast: true);
 
+		public override void Stop()
+		{
+			if (_isBotting)
+			{
+				StopBot();
+			}
+			else if (_replayMode)
+			{
+				FinishReplay();
+			}
+		}
+
 		public override void Restart()
 		{
 			_ = StatableCore!; // otherwise unused due to loadstating via MainForm; however this service is very much required so the property needs to be present
@@ -272,16 +284,6 @@ public override void Restart()
 				_dataSize = 1;
 			}
 
-			if (_isBotting)
-			{
-				StopBot();
-			}
-			else if (_replayMode)
-			{
-				FinishReplay();
-			}
-
-
 			if (_lastRom != MainForm.CurrentlyOpenRom)
 			{
 				_lastRom = MainForm.CurrentlyOpenRom;

src/BizHawk.Client.EmuHawk/tools/Debugger/GenericDebugger.IToolForm.cs

@@ -112,10 +112,14 @@ private void FullUpdate()
 			BreakPointControl1.UpdateValues();
 		}
 
+		public override void Stop()
+		{
+			DisengageDebugger();
+		}
+
 		public override void Restart()
 		{
 			UpdateCapabilitiesProps();
-			DisengageDebugger();
 			EngageDebugger();
 		}
 

src/BizHawk.Client.EmuHawk/tools/Lua/LuaConsole.cs

@@ -163,6 +163,7 @@ public LuaConsole()
 		}
 
 		private LuaLibraries LuaImp;
+		private List<LuaFile> _scriptsToRestart = new();
 
 		private ConsoleLuaLibrary _consoleLib;
 
@@ -198,10 +199,22 @@ private void BranchesMarkersSplit_SplitterMoved(object sender, SplitterEventArgs
 			Settings.SplitDistance = splitContainer1.SplitterDistance;
 		}
 
-		public override void Restart()
+		public override void Stop()
 		{
-			List<LuaFile> runningScripts = new();
+			if (LuaImp is not null && !LuaImp.IsRebootingCore)
+			{
+				_scriptsToRestart = LuaImp.ScriptList.Where(lf => lf.Enabled).ToList();
 
+				// we don't use _scriptsToRestart here, in case something is somehow partially active
+				foreach (var file in LuaImp.ScriptList)
+				{
+					file.Stop();
+				}
+			}
+		}
+
+		public override void Restart()
+		{
 			ApiContainer apiContainer = ApiManager.RestartLua(
 				Emulator.ServiceProvider,
 				WriteToOutputWindow,
@@ -215,23 +228,11 @@ public override void Restart()
 				Game,
 				DialogController);
 
-			// Things we need to do with the existing LuaImp before we can make a new one
-			if (LuaImp is not null)
+			if (LuaImp is not null && LuaImp.IsRebootingCore)
 			{
-				if (LuaImp.IsRebootingCore)
-				{
-					// Even if the lua console is self-rebooting from client.reboot_core() we still want to re-inject dependencies
-					LuaImp.Restart(Emulator.ServiceProvider, Config, apiContainer);
-					return;
-				}
-
-				runningScripts = LuaImp.ScriptList.Where(lf => lf.Enabled).ToList();
-
-				// we don't use runningScripts here as the other scripts need to be stopped too
-				foreach (var file in LuaImp.ScriptList)
-				{
-					file.Stop();
-				}
+				// Even if the lua console is self-rebooting from client.reboot_core() we still want to re-inject dependencies
+				LuaImp.Restart(Emulator.ServiceProvider, Config, apiContainer);
+				return;
 			}
 
 			_openedFiles = new(_openedFiles, onChanged: SessionChangedCallback);
@@ -255,7 +256,7 @@ public override void Restart()
 				.Select(static f => $"{f.Library}.{f.Name}")
 				.ToArray());
 
-			foreach (var file in runningScripts)
+			foreach (var file in _scriptsToRestart)
 			{
 				EnableLuaFile(file);
 			}

src/BizHawk.Client.EmuHawk/tools/ToolFormBase.cs

@@ -31,6 +31,8 @@ public class ToolFormBase : FormBase, IToolForm, IDialogParent
 		public virtual bool IsActive => IsHandleCreated && !IsDisposed;
 		public virtual bool IsLoaded => IsActive;
 
+		public virtual void Stop() {}
+
 		public virtual void Restart() {}
 
 		public void SetToolFormBaseProps(

src/BizHawk.Client.EmuHawk/tools/ToolManager.cs

@@ -41,6 +41,7 @@ static ToolManager()
 		// For instance, add an IToolForm property called UsesCheats, so that a UpdateCheatRelatedTools() method can update all tools of this type
 		// Also a UsesRam, and similar method
 		private readonly List<IToolForm> _tools = new List<IToolForm>();
+		private readonly List<IToolForm> _toolsToRestart = new();
 
 		/// <summary>
 		/// Initializes a new instance of the <see cref="ToolManager"/> class.
@@ -582,6 +583,15 @@ public void GeneralUpdateActiveExtTools()
 			}
 		}
 
+		public void Stop()
+		{
+			foreach (IToolForm tool in _tools.Where(static t => t.IsActive))
+			{
+				_toolsToRestart.Add(tool);
+				tool.Stop();
+			}
+		}
+
 		public void Restart(Config config, IEmulator emulator, IGameInfo game)
 		{
 			_config = config;
@@ -597,7 +607,7 @@ public void Restart(Config config, IEmulator emulator, IGameInfo game)
 				if (ServiceInjector.UpdateServices(_emulator.ServiceProvider, tool)
 					&& (tool is not IExternalToolForm || ApiInjector.UpdateApis(GetOrInitApiProvider, tool)))
 				{
-					if (tool.IsActive) tool.Restart();
+					if (_toolsToRestart.Contains(tool)) tool.Restart();
 				}
 				else
 				{
@@ -611,6 +621,8 @@ public void Restart(Config config, IEmulator emulator, IGameInfo game)
 				tool.Close();
 				_tools.Remove(tool);
 			}
+
+			_toolsToRestart.Clear();
 		}
 
 		/// <summary>