Fix possible crash when load task is running on exit

src/jobs/cliploadtask.cpp

@@ -735,11 +735,13 @@ void ClipLoadTask::run()
 
 void ClipLoadTask::abort()
 {
-    Fun undo = []() { return true; };
-    Fun redo = []() { return true; };
     m_progress = 100;
     pCore->taskManager.taskDone(m_owner.second, this);
-    qDebug()<<pCore->projectItemModel()->getClipByBinID(QString::number(m_owner.second))->clipUrl();
+    if (pCore->taskManager.isBlocked()) {
+        return;
+    }
+    Fun undo = []() { return true; };
+    Fun redo = []() { return true; };
     QString resource = Xml::getXmlProperty(m_xml, QStringLiteral("resource"));
     if (!m_softDelete) {
         auto binClip = pCore->projectItemModel()->getClipByBinID(QString::number(m_owner.second));

src/jobs/taskmanager.cpp

@@ -22,6 +22,7 @@ SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
 TaskManager::TaskManager(QObject *parent)
     : QObject(parent)
     , m_tasksListLock(QReadWriteLock::Recursive)
+    , m_blockUpdates(false)
 {
     int maxThreads = qMin(4, QThread::idealThreadCount() - 1);
     m_taskPool.setMaxThreadCount(qMax(maxThreads, 1));
@@ -33,6 +34,11 @@ TaskManager::~TaskManager()
     slotCancelJobs();
 }
 
+bool TaskManager::isBlocked() const
+{
+    return m_blockUpdates;
+}
+
 void TaskManager::updateConcurrency()
 {
     m_transcodePool.setMaxThreadCount(KdenliveSettings::proxythreads());
@@ -124,6 +130,7 @@ void TaskManager::slotCancelJobs()
 {
     m_tasksListLock.lockForRead();
     // See if there is already a task for this MLT service and resource.
+    m_blockUpdates = true;
     for (const auto &task : m_taskList) {
         for (AbstractTask* t : task.second) {
             // If so, then just add ourselves to be notified upon completion.
@@ -133,6 +140,7 @@ void TaskManager::slotCancelJobs()
     m_tasksListLock.unlock();
     m_taskPool.waitForDone();
     m_transcodePool.waitForDone();
+    m_blockUpdates = false;
     updateJobCount();
 }
 

src/jobs/taskmanager.h

@@ -63,6 +63,9 @@ public:
     /** @brief Update the number of concurrent jobs allowed */
     void updateConcurrency();
 
+    /** @brief We are aborting all tasks and don't want them to send any updates */
+    bool isBlocked() const;
+
     /** @brief return the message of a given job on a given clip (message, detailed log)*/
     //QPair<QString, QString> getJobMessageForClip(int jobId, const QString &binId) const;
 
@@ -79,6 +82,7 @@ private:
     QThreadPool m_transcodePool;
     std::unordered_map<int, std::vector<AbstractTask*> > m_taskList;
     mutable QReadWriteLock m_tasksListLock;
+    bool m_blockUpdates;
 
 signals:
     void jobCount(int);