Fix input dialogs causing crash on shutdown

lib/advanced-scene-switcher.cpp

@@ -470,7 +470,7 @@ void SwitcherData::Start()
 	}
 }
 
-bool CloseAllInputDialogs();
+void CloseAllInputDialogs();
 void StopAndClearAllActionQueues();
 
 void SwitcherData::Stop()
@@ -482,23 +482,10 @@ void SwitcherData::Stop()
 		GetMacroWaitCV().notify_all();
 		GetMacroTransitionCV().notify_all();
 		StopAndClearAllActionQueues();
-
-		// Not waiting if a dialog was closed is a workaround to avoid
-		// deadlocks when a variable input dialog is opened while Stop()
-		// is called.
-		//
-		// The QEventLoop handling the dialog would not exit until Stop()
-		// would return, which itself would wait for the switcher thread
-		// to complete, which itself is blocked by the variable input
-		// dialog.
-		//
-		// Must be reworked in the future, as this will not go well when
-		// OBS is shutting down and a dialog is still opened.
-		if (!CloseAllInputDialogs()) {
-			th->wait();
-			delete th;
-			th = nullptr;
-		}
+		CloseAllInputDialogs();
+		th->wait();
+		delete th;
+		th = nullptr;
 		writeToStatusFile("Advanced Scene Switcher stopped");
 	}
 

lib/macro/macro-action-variable.cpp

@@ -181,18 +181,23 @@ void MacroActionVariable::SetToSceneItemName(Variable *var)
 }
 
 struct AskForInputParams {
+	AskForInputParams(const QString &prompt_, const QString &placeholder_)
+		: prompt(prompt_), placeholder(placeholder_){};
 	QString prompt;
 	QString placeholder;
 	std::optional<std::string> result;
+	std::atomic_bool resultReady = {false};
 };
 
 static void askForInput(void *param)
 {
-	auto parameters = static_cast<AskForInputParams *>(param);
+	auto parameters =
+		*static_cast<std::shared_ptr<AskForInputParams> *>(param);
 	auto dialog = new NonModalMessageDialog(
-		parameters->prompt, NonModalMessageDialog::Type::INPUT);
+		parameters->prompt, NonModalMessageDialog::Type::INPUT, false);
 	dialog->SetInput(parameters->placeholder);
 	parameters->result = dialog->GetInput();
+	parameters->resultReady = true;
 }
 
 bool MacroActionVariable::PerformAction()
@@ -264,7 +269,7 @@ bool MacroActionVariable::PerformAction()
 		return true;
 	}
 	case Type::USER_INPUT: {
-		AskForInputParams params{
+		auto params = std::make_shared<AskForInputParams>(
 			_useCustomPrompt
 				? QString::fromStdString(_inputPrompt)
 				: QString(obs_module_text(
@@ -273,13 +278,19 @@ bool MacroActionVariable::PerformAction()
 						  var->Name())),
 			_useCustomPrompt && _useInputPlaceholder
 				? QString::fromStdString(_inputPlaceholder)
-				: "",
-			{}};
-		obs_queue_task(OBS_TASK_UI, askForInput, &params, true);
-		if (!params.result.has_value()) {
-			return false;
+				: "");
+		obs_queue_task(OBS_TASK_UI, askForInput, &params, false);
+		while (!params->resultReady) {
+			if (GetMacro()->GetStop()) {
+				return false;
+			}
+			std::this_thread::sleep_for(
+				std::chrono::milliseconds(100));
 		}
-		var->SetValue(*params.result);
+		if (!params->result.has_value()) {
+			return true;
+		}
+		var->SetValue(*params->result);
 		return true;
 	}
 	case Type::ENV_VARIABLE: {

lib/utils/non-modal-dialog.cpp

@@ -1,24 +1,40 @@
 #include "non-modal-dialog.hpp"
 #include "obs-module-helper.hpp"
 
-#include <QMainWindow>
-#include <QLayout>
-#include <QLabel>
-#include <QDialogButtonBox>
+#include <atomic>
+#include <mutex>
 #include <obs-frontend-api.h>
+#include <QDialogButtonBox>
+#include <QLabel>
+#include <QLayout>
+#include <QMainWindow>
+#include <QCoreApplication>
 
 namespace advss {
 
+static std::mutex mutex;
+static std::vector<NonModalMessageDialog *> dialogs;
+
 QWidget *GetSettingsWindow();
 
 NonModalMessageDialog::NonModalMessageDialog(const QString &message,
-					     bool question)
-	: NonModalMessageDialog(message, question ? Type::QUESTION : Type::INFO)
+					     bool question,
+					     bool focusAdvssWindow)
+	: NonModalMessageDialog(message, question ? Type::QUESTION : Type::INFO,
+				focusAdvssWindow)
 {
 }
 
-NonModalMessageDialog::NonModalMessageDialog(const QString &message, Type type)
-	: QDialog(GetSettingsWindow()
+NonModalMessageDialog::~NonModalMessageDialog()
+{
+	std::lock_guard<std::mutex> lock(mutex);
+	dialogs.erase(std::remove(dialogs.begin(), dialogs.end(), this),
+		      dialogs.end());
+}
+
+NonModalMessageDialog::NonModalMessageDialog(const QString &message, Type type,
+					     bool focusAdvssWindow)
+	: QDialog(focusAdvssWindow && GetSettingsWindow()
 			  ? GetSettingsWindow()
 			  : static_cast<QMainWindow *>(
 				    obs_frontend_get_main_window())),
@@ -65,6 +81,9 @@ NonModalMessageDialog::NonModalMessageDialog(const QString &message, Type type)
 	}
 	}
 	setLayout(layout);
+
+	std::lock_guard<std::mutex> lock(mutex);
+	dialogs.emplace_back(this);
 }
 
 QMessageBox::StandardButton NonModalMessageDialog::ShowMessage()
@@ -83,7 +102,8 @@ std::optional<std::string> NonModalMessageDialog::GetInput()
 	_inputEdit->setPlainText(_inputEdit->toPlainText());
 
 	exec();
-	this->deleteLater();
+	deleteLater();
+
 	if (_answer == QMessageBox::Yes) {
 		return _input.toStdString();
 	}
@@ -115,28 +135,23 @@ void NonModalMessageDialog::InputChanged()
 	updateGeometry();
 }
 
-bool CloseAllInputDialogs()
+void CloseAllInputDialogs()
 {
-	auto window =
-		static_cast<QMainWindow *>(obs_frontend_get_main_window());
-	if (!window) {
-		return false;
+	std::lock_guard<std::mutex> lock(mutex);
+	if (dialogs.empty()) {
+		return;
 	}
-
-	bool closedAtLeastOneDialog = false;
-	QList<QWidget *> widgets = window->findChildren<QWidget *>();
-	for (auto &widget : widgets) {
-		auto dialog = qobject_cast<NonModalMessageDialog *>(widget);
-		if (!dialog) {
-			continue;
-		}
-		if (dialog->GetType() != NonModalMessageDialog::Type::INPUT) {
-			continue;
-		}
-		dialog->close();
-		closedAtLeastOneDialog = true;
-	}
-	return closedAtLeastOneDialog;
+	obs_queue_task(
+		OBS_TASK_UI,
+		[](void *) {
+			for (const auto dialog : dialogs) {
+				if (dialog->GetType() ==
+				    NonModalMessageDialog::Type::INPUT) {
+					dialog->close();
+				}
+			}
+		},
+		nullptr, true);
 }
 
 } // namespace advss

lib/utils/non-modal-dialog.hpp

@@ -7,7 +7,7 @@
 
 namespace advss {
 
-bool CloseAllInputDialogs();
+void CloseAllInputDialogs();
 
 class NonModalMessageDialog : public QDialog {
 	Q_OBJECT
@@ -15,8 +15,11 @@ class NonModalMessageDialog : public QDialog {
 public:
 	enum class Type { INFO, QUESTION, INPUT };
 
-	NonModalMessageDialog(const QString &message, Type);
-	NonModalMessageDialog(const QString &message, bool question);
+	NonModalMessageDialog(const QString &message, Type,
+			      bool focusAdvssWindow = false);
+	NonModalMessageDialog(const QString &message, bool question,
+			      bool focusAdvssWindow = false);
+	~NonModalMessageDialog();
 	QMessageBox::StandardButton ShowMessage();
 	std::optional<std::string> GetInput();
 	Type GetType() const { return _type; }