From 0835bc27d6c2949759c3e125587e3448e25745b7 Mon Sep 17 00:00:00 2001
From: letsfindaway <me@letsfindaway.de>
Date: Fri, 25 Oct 2024 17:22:27 +0200
Subject: [PATCH] fix: crash when closing while scene is loading

- OpenBoard crashes when it is terminated while a scene is loading
  in background
- the timer used for background loading still runs and accesses
  resources no longer available
- add a flag isClosing to UBApplication
- check flag in timer routine in UBSceneCache
---
 src/core/UBApplication.cpp | 4 ++++
 src/core/UBApplication.h   | 2 ++
 src/core/UBSceneCache.cpp  | 7 +++++++
 3 files changed, 13 insertions(+)

diff --git a/src/core/UBApplication.cpp b/src/core/UBApplication.cpp
index 9e74e09a3..e7d7853ab 100644
--- a/src/core/UBApplication.cpp
+++ b/src/core/UBApplication.cpp
@@ -79,6 +79,8 @@ UBDocumentController* UBApplication::documentController = 0;
 
 UBMainWindow* UBApplication::mainWindow = 0;
 
+bool UBApplication::isClosing = false;
+
 const QString UBApplication::mimeTypeUniboardDocument = QString("application/vnd.mnemis-uniboard-document");
 const QString UBApplication::mimeTypeUniboardPage = QString("application/vnd.mnemis-uniboard-page");
 const QString UBApplication::mimeTypeUniboardPageItem =  QString("application/vnd.mnemis-uniboard-page-item");
@@ -507,6 +509,8 @@ void UBApplication::closeEvent(QCloseEvent *event)
 
 void UBApplication::closing()
 {
+    isClosing = true;
+
     if (UBSettings::settings()->emptyTrashForOlderDocuments->get().toBool())
     {
         UBDocumentTreeModel *docModel = UBPersistenceManager::persistenceManager()->mDocumentTreeStructureModel;
diff --git a/src/core/UBApplication.h b/src/core/UBApplication.h
index 9347c5b63..ab13cf832 100644
--- a/src/core/UBApplication.h
+++ b/src/core/UBApplication.h
@@ -78,6 +78,8 @@ class UBApplication : public SingleApplication
 
         static UBMainWindow* mainWindow;
 
+        static bool isClosing;
+
         static UBApplication* app()
         {
             return dynamic_cast<UBApplication*>qApp;
diff --git a/src/core/UBSceneCache.cpp b/src/core/UBSceneCache.cpp
index a1c788cdc..fb5896d3a 100644
--- a/src/core/UBSceneCache.cpp
+++ b/src/core/UBSceneCache.cpp
@@ -322,6 +322,13 @@ void UBSceneCache::SceneCacheEntry::startLoading()
 {
     mTimer = new QTimer;
     QObject::connect(mTimer, &QTimer::timeout, mTimer, [this](){
+        if (UBApplication::isClosing)
+        {
+            mTimer->stop();
+            delete mTimer;
+            return;
+        }
+
         if (mContext)
         {
             mContext->step();