Add option to prompt user for value to be assigned to variable

src/advanced-scene-switcher.cpp

@@ -439,6 +439,8 @@ void SwitcherData::Start()
 	}
 }
 
+bool CloseAllInputDialogs();
+
 void SwitcherData::Stop()
 {
 	if (th && th->isRunning()) {
@@ -447,10 +449,23 @@ void SwitcherData::Stop()
 		abortMacroWait = true;
 		macroWaitCv.notify_all();
 		macroTransitionCv.notify_all();
-		th->wait();
-		delete th;
-		th = nullptr;
 
+		// 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;
+		}
 		writeToStatusFile("Advanced Scene Switcher stopped");
 	}