From efde75877dad26a7f36133969a3acd70339eebee Mon Sep 17 00:00:00 2001
From: Magnus Norddahl <dpjudas@users.noreply.github.com>
Date: Sun, 31 Dec 2023 05:08:17 +0100
Subject: [PATCH] Fix the abort button

---
 src/common/widgets/netstartwindow.cpp | 33 +++++++++++++++++++++++----
 src/common/widgets/netstartwindow.h   |  3 +++
 2 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/src/common/widgets/netstartwindow.cpp b/src/common/widgets/netstartwindow.cpp
index 00c93fc7c6..ee6f76fe12 100644
--- a/src/common/widgets/netstartwindow.cpp
+++ b/src/common/widgets/netstartwindow.cpp
@@ -1,6 +1,7 @@
 
 #include "netstartwindow.h"
 #include "version.h"
+#include "engineerrors.h"
 #include <zwidget/core/timer.h>
 #include <zwidget/widgets/textlabel/textlabel.h>
 #include <zwidget/widgets/pushbutton/pushbutton.h>
@@ -39,12 +40,23 @@ bool NetStartWindow::RunMessageLoop(bool (*newtimer_callback)(void*), void* newu
 
 	Instance->timer_callback = newtimer_callback;
 	Instance->userdata = newuserdata;
+	Instance->CallbackException = {};
 
 	DisplayWindow::RunLoop();
 
 	Instance->timer_callback = nullptr;
 	Instance->userdata = nullptr;
 
+	if (Instance->CallbackException)
+		std::rethrow_exception(Instance->CallbackException);
+
+	// Even though the comment in FBasicStartupScreen::NetLoop says we should return false, the old code actually throws an exception!
+	// This effectively also means the function always returns true...
+	if (!Instance->exitreason)
+	{
+		throw CExitEvent(0);
+	}
+
 	return Instance->exitreason;
 }
 
@@ -75,7 +87,7 @@ NetStartWindow::NetStartWindow(const std::string& message, int maxpos) : Widget(
 
 void NetStartWindow::SetProgress(int newpos)
 {
-	if (pos != newpos)
+	if (pos != newpos && maxpos > 1)
 	{
 		pos = newpos;
 		FString message;
@@ -110,9 +122,22 @@ void NetStartWindow::OnGeometryChanged()
 
 void NetStartWindow::OnCallbackTimerExpired()
 {
-	if (timer_callback && timer_callback(userdata))
+	if (timer_callback)
 	{
-		exitreason = true;
-		DisplayWindow::ExitLoop();
+		bool result = false;
+		try
+		{
+			result = timer_callback(userdata);
+		}
+		catch (...)
+		{
+			CallbackException = std::current_exception();
+		}
+
+		if (result)
+		{
+			exitreason = true;
+			DisplayWindow::ExitLoop();
+		}
 	}
 }
diff --git a/src/common/widgets/netstartwindow.h b/src/common/widgets/netstartwindow.h
index c02927f0e9..8dffa4d709 100644
--- a/src/common/widgets/netstartwindow.h
+++ b/src/common/widgets/netstartwindow.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <zwidget/core/widget.h>
+#include <stdexcept>
 
 class TextLabel;
 class PushButton;
@@ -39,5 +40,7 @@ private:
 
 	bool exitreason = false;
 
+	std::exception_ptr CallbackException;
+
 	static NetStartWindow* Instance;
 };