logic: terminating all running tasks before closing the application (issue #343)

src/lib/data/parser/TaskParseWrapper.cpp

@@ -54,3 +54,8 @@ void TaskParseWrapper::doReset(std::shared_ptr<Blackboard> blackboard)
 {
 	m_taskRunner->reset();
 }
+
+void TaskParseWrapper::doTerminate()
+{
+	m_taskRunner->terminate();
+}

src/lib/data/parser/TaskParseWrapper.h

@@ -28,6 +28,7 @@ private:
 	virtual TaskState doUpdate(std::shared_ptr<Blackboard> blackboard);
 	virtual void doExit(std::shared_ptr<Blackboard> blackboard);
 	virtual void doReset(std::shared_ptr<Blackboard> blackboard);
+	virtual void doTerminate();
 
 	PersistentStorage* m_storage;
 

src/lib/utility/ScopedFunctor.cpp

@@ -1,5 +1,10 @@
 #include "utility/ScopedFunctor.h"
 
+ScopedFunctor::ScopedFunctor()
+	: m_onDestroy([](){})
+{
+}
+
 ScopedFunctor::ScopedFunctor(std::function<void(void)> onDestroy)
 	: m_onDestroy(onDestroy)
 {

src/lib/utility/ScopedFunctor.h

@@ -6,6 +6,7 @@
 class ScopedFunctor
 {
 public:
+	ScopedFunctor();
 	ScopedFunctor(std::function<void(void)> onDestroy);
 	~ScopedFunctor();
 

src/lib/utility/scheduling/Task.cpp

@@ -48,3 +48,8 @@ void Task::reset(std::shared_ptr<Blackboard> blackboard)
 	m_enterCalled = false;
 	m_exitCalled = false;
 }
+
+void Task::terminate()
+{
+}
+

src/lib/utility/scheduling/Task.h

@@ -23,6 +23,7 @@ public:
 
 	TaskState update(std::shared_ptr<Blackboard> blackboard);
 	void reset(std::shared_ptr<Blackboard> blackboard);
+	virtual void terminate(); // caution: this should only be called just before quitting the app.
 
 private:
 	virtual void doEnter(std::shared_ptr<Blackboard> blackboard) = 0;

src/lib/utility/scheduling/TaskDecorator.cpp

@@ -13,3 +13,8 @@ std::shared_ptr<TaskDecorator> TaskDecorator::addChildTask(std::shared_ptr<Task>
 	setTask(child);
 	return shared_from_this();
 }
+
+void TaskDecorator::terminate()
+{
+	doTerminate();
+}

src/lib/utility/scheduling/TaskDecorator.h

@@ -15,6 +15,10 @@ public:
 	std::shared_ptr<TaskDecorator> addChildTask(std::shared_ptr<Task> child);
 
 	virtual void setTask(std::shared_ptr<Task> task) = 0;
+	virtual void terminate();
+
+private:
+	virtual void doTerminate() = 0;
 };
 
 #endif // TASK_DECORATOR_H

src/lib/utility/scheduling/TaskDecoratorRepeat.cpp

@@ -48,3 +48,8 @@ void TaskDecoratorRepeat::doReset(std::shared_ptr<Blackboard> blackboard)
 {
 	m_taskRunner->reset();
 }
+
+void TaskDecoratorRepeat::doTerminate()
+{
+	m_taskRunner->terminate();
+}

src/lib/utility/scheduling/TaskDecoratorRepeat.h

@@ -24,6 +24,7 @@ private:
 	virtual TaskState doUpdate(std::shared_ptr<Blackboard> blackboard);
 	virtual void doExit(std::shared_ptr<Blackboard> blackboard);
 	virtual void doReset(std::shared_ptr<Blackboard> blackboard);
+	virtual void doTerminate();
 
 	std::shared_ptr<TaskRunner> m_taskRunner;
 	const ConditionType m_condition;

src/lib/utility/scheduling/TaskGroup.cpp

@@ -27,4 +27,9 @@ std::shared_ptr<TaskGroup> TaskGroup::addChildTasks(std::shared_ptr<Task> child1
 	addTask(child2);
 	addTask(child3);
 	return shared_from_this();
-}
+}
+
+void TaskGroup::terminate()
+{
+	doTerminate();
+}

src/lib/utility/scheduling/TaskGroup.h

@@ -18,6 +18,10 @@ public:
 	std::shared_ptr<TaskGroup> addChildTasks(std::shared_ptr<Task> child1, std::shared_ptr<Task> child2, std::shared_ptr<Task> child3);
 
 	virtual void addTask(std::shared_ptr<Task> task) = 0;
+	virtual void terminate();
+
+private:
+	virtual void doTerminate() = 0;
 };
 
 

src/lib/utility/scheduling/TaskGroupParallel.cpp

@@ -73,6 +73,19 @@ void TaskGroupParallel::doReset(std::shared_ptr<Blackboard> blackboard)
 	}
 }
 
+void TaskGroupParallel::doTerminate()
+{
+	for (size_t i = 0; i < m_tasks.size(); i++)
+	{
+		m_tasks[i]->taskRunner->terminate();
+		if (m_tasks[i]->thread)
+		{
+			m_tasks[i]->thread->detach();
+			m_tasks[i]->thread.reset();
+		}
+	}
+}
+
 void TaskGroupParallel::processTaskThreaded(std::shared_ptr<TaskInfo> taskInfo, std::shared_ptr<Blackboard> blackboard)
 {
 	ScopedFunctor functor([&](){

src/lib/utility/scheduling/TaskGroupParallel.h

@@ -33,6 +33,7 @@ private:
 	virtual TaskState doUpdate(std::shared_ptr<Blackboard> blackboard);
 	virtual void doExit(std::shared_ptr<Blackboard> blackboard);
 	virtual void doReset(std::shared_ptr<Blackboard> blackboard);
+	virtual void doTerminate();
 
 	void processTaskThreaded(std::shared_ptr<TaskInfo> taskInfo, std::shared_ptr<Blackboard> blackboard);
 	int getActveTaskCount() const;

src/lib/utility/scheduling/TaskGroupSelector.cpp

@@ -54,3 +54,11 @@ void TaskGroupSelector::doReset(std::shared_ptr<Blackboard> blackboard)
 		m_taskRunners[i]->reset();
 	}
 }
+
+void TaskGroupSelector::doTerminate()
+{
+	for (size_t i = 0; i < m_taskRunners.size(); i++)
+	{
+		m_taskRunners[i]->terminate();
+	}
+}

src/lib/utility/scheduling/TaskGroupSelector.h

@@ -18,6 +18,7 @@ private:
 	virtual TaskState doUpdate(std::shared_ptr<Blackboard> blackboard);
 	virtual void doExit(std::shared_ptr<Blackboard> blackboard);
 	virtual void doReset(std::shared_ptr<Blackboard> blackboard);
+	virtual void doTerminate();
 
 	std::vector<std::shared_ptr<TaskRunner>> m_taskRunners;
 	int m_taskIndex;

src/lib/utility/scheduling/TaskGroupSequence.cpp

@@ -54,3 +54,11 @@ void TaskGroupSequence::doReset(std::shared_ptr<Blackboard> blackboard)
 		m_taskRunners[i]->reset();
 	}
 }
+
+void TaskGroupSequence::doTerminate()
+{
+	for (size_t i = 0; i < m_taskRunners.size(); i++)
+	{
+		m_taskRunners[i]->terminate();
+	}
+}

src/lib/utility/scheduling/TaskGroupSequence.h

@@ -18,6 +18,7 @@ private:
 	virtual TaskState doUpdate(std::shared_ptr<Blackboard> blackboard);
 	virtual void doExit(std::shared_ptr<Blackboard> blackboard);
 	virtual void doReset(std::shared_ptr<Blackboard> blackboard);
+	virtual void doTerminate();
 
 	std::vector<std::shared_ptr<TaskRunner>> m_taskRunners;
 	int m_taskIndex;

src/lib/utility/scheduling/TaskRunner.cpp

@@ -26,4 +26,13 @@ void TaskRunner::reset()
 	m_reset = true;
 }
 
+void TaskRunner::terminate()
+{
+	if (m_task)
+	{
+		m_task->terminate();
+	}
+}
+
+
 

src/lib/utility/scheduling/TaskRunner.h

@@ -13,10 +13,11 @@ public:
 
 	Task::TaskState update(std::shared_ptr<Blackboard> blackboard);
 	void reset();
+	void terminate(); // caution: this should only be called just before quitting the app.
 
 private:
 	std::shared_ptr<Task> m_task;
 	bool m_reset;
 };
 
-#endif // TASK_H
+#endif // TASK_RUNNER_H

src/lib/utility/scheduling/TaskScheduler.cpp

@@ -161,6 +161,7 @@ void TaskScheduler::processTasks()
 
 					if (!m_loopIsRunning)
 					{
+						runner->terminate();
 						break;
 					}
 				}

src/lib_cxx/project/SourceGroupCxx.cpp

@@ -35,14 +35,17 @@ bool SourceGroupCxx::prepareRefresh()
 	{
 		MessageStatus("Can't refresh project").dispatch();
 
-		if (Application::getInstance()->hasGUI())
+		if (std::shared_ptr<Application> application = Application::getInstance())
 		{
-			std::vector<std::string> options;
-			options.push_back("Ok");
-			Application::getInstance()->handleDialog(
-				"Can't refresh. The compilation database of the project does not exist anymore: " + cdbPath.str(),
-				options
-			);
+			if (application->hasGUI())
+			{
+				std::vector<std::string> options;
+				options.push_back("Ok");
+				application->handleDialog(
+					"Can't refresh. The compilation database of the project does not exist anymore: " + cdbPath.str(),
+					options
+				);
+			}
 		}
 		return false;
 	}

src/lib_java/project/SourceGroupJava.cpp

@@ -51,18 +51,20 @@ void SourceGroupJava::fetchAllSourceFilePaths()
 	std::vector<FilePath> sourcePaths;
 	if (m_settings->getAbsoluteMavenProjectFilePath().exists())
 	{
-		if (Application::getInstance()->hasGUI())
+		std::shared_ptr<Application> application = Application::getInstance();
+
+		if (application && application->hasGUI())
 		{
-			Application::getInstance()->getDialogView()->showStatusDialog("Preparing Project", "Maven\nFetching Source Directories");
+			application->getDialogView()->showStatusDialog("Preparing Project", "Maven\nFetching Source Directories");
 		}
 
 		const FilePath mavenPath(ApplicationSettings::getInstance()->getMavenPath());
 		const FilePath projectRootPath = m_settings->getAbsoluteMavenProjectFilePath().parentDirectory();
 		sourcePaths = utility::mavenGetAllDirectoriesFromEffectivePom(mavenPath, projectRootPath, m_settings->getShouldIndexMavenTests());
 
-		if (Application::getInstance()->hasGUI())
+		if (application && application->hasGUI())
 		{
-			Application::getInstance()->getDialogView()->hideStatusDialog();
+			application->getDialogView()->hideStatusDialog();
 		}
 	}
 	else
@@ -159,23 +161,29 @@ bool SourceGroupJava::prepareJavaEnvironment()
 
 bool SourceGroupJava::prepareMavenData()
 {
-	if (m_settings->getAbsoluteMavenProjectFilePath().exists())
+	if (m_settings && m_settings->getAbsoluteMavenProjectFilePath().exists())
 	{
 		const FilePath mavenPath = ApplicationSettings::getInstance()->getMavenPath();
 		const FilePath projectRootPath = m_settings->getAbsoluteMavenProjectFilePath().parentDirectory();
 
-		if (Application::getInstance()->hasGUI())
+		ScopedFunctor dialogHider;
+
+		std::shared_ptr<Application> application = Application::getInstance();
+
+		if (application && application->hasGUI())
 		{
-			ScopedFunctor dialogHider([](){
+			// this makes sure to hide the dialog when leaving this method.
+			dialogHider = ScopedFunctor([](){
 				Application::getInstance()->getDialogView()->hideStatusDialog();
 			});
-
 			Application::getInstance()->getDialogView()->showStatusDialog("Preparing Project", "Maven\nGenerating Source Files");
-			bool success = utility::mavenGenerateSources(
-				mavenPath, projectRootPath
-			);
+		}
 
-			if (!success)
+		bool success = utility::mavenGenerateSources(mavenPath, projectRootPath);
+
+		if (!success)
+		{
+			if (application && application->hasGUI())
 			{
 				const std::string dialogMessage =
 					"Sourcetrail was unable to locate Maven on this machine.\n"
@@ -184,11 +192,15 @@ bool SourceGroupJava::prepareMavenData()
 				MessageStatus(dialogMessage, true, false).dispatch();
 
 				Application::getInstance()->handleDialog(dialogMessage);
-				return false;
 			}
+			return false;
+		}
 
+		if (application && application->hasGUI())
+		{
 			Application::getInstance()->getDialogView()->showStatusDialog("Preparing Project", "Maven\nExporting Dependencies");
 		}
+
 		utility::mavenCopyDependencies(
 			mavenPath, projectRootPath, m_settings->getAbsoluteMavenDependenciesDirectory()
 		);
@@ -235,11 +247,13 @@ std::vector<FilePath> SourceGroupJava::getClassPath()
 
 std::set<FilePath> SourceGroupJava::fetchRootDirectories()
 {
-	if (Application::getInstance()->hasGUI())
+	if (std::shared_ptr<Application> application = Application::getInstance())
 	{
-		Application::getInstance()->getDialogView()->showStatusDialog("Preparing Project", "Gathering Root\nDirectories");
+		if (application->hasGUI())
+		{
+			application->getDialogView()->showStatusDialog("Preparing Project", "Gathering Root\nDirectories");
+		}
 	}
-
 	std::set<FilePath> rootDirectories;
 
 	std::shared_ptr<JavaEnvironment> javaEnvironment = JavaEnvironmentFactory::getInstance()->createEnvironment();