logic: multithreaded parsing

* modified the TaskParseCxx to be able to run multiple times in parallel
* made FileRegister threadsafe and changed a lot of its mechanisms
* added TaskGroupParallel that runs all children in parallel
* added TaskParseWrapper that acts as a decorator to execute some code before and after parsing.
* implemented task setup in project with 4 parsing threads
* removed SimpleTask as it was only used as interface for the LambdaTask

src/app/data/parser/cxx/TaskParseWrapper.cpp

@@ -0,0 +1,57 @@
+#include "data/parser/cxx/TaskParseWrapper.h"
+
+#include "data/PersistentStorage.h"
+#include "utility/file/FileRegister.h"
+#include "utility/messaging/type/MessageFinishedParsing.h"
+#include "utility/messaging/type/MessageStatus.h"
+#include "utility/utility.h"
+
+TaskParseWrapper::TaskParseWrapper(
+	std::shared_ptr<Task> child,
+	PersistentStorage* storage,
+	std::shared_ptr<FileRegister> fileRegister
+)
+	: m_child(child)
+	, m_storage(storage)
+	, m_fileRegister(fileRegister)
+{
+}
+
+void TaskParseWrapper::enter()
+{
+	m_start = utility::durationStart();
+	m_storage->startParsing();
+
+	m_child->enter();
+}
+
+Task::TaskState TaskParseWrapper::update()
+{
+	return m_child->update();
+}
+
+void TaskParseWrapper::exit()
+{
+	m_child->exit();
+
+	MessageStatus("building search index", false, true).dispatch();
+
+	m_storage->finishParsing();
+
+	MessageFinishedParsing(
+		m_fileRegister->getParsedSourceFilesCount(),
+		m_fileRegister->getSourceFilesCount(),
+		utility::duration(m_start)
+	).dispatch();
+}
+
+void TaskParseWrapper::interrupt()
+{
+	MessageStatus("analyzing files interrupted", false, true).dispatch();
+	m_child->interrupt();
+}
+
+void TaskParseWrapper::revert()
+{
+	m_child->revert();
+}