File::getLock

public function getLock()
{
	if ($this->isLoadedAttribute('lock'))
	{
		return $this->lock;
	}

	$lock = ObjectLock::load(['OBJECT_ID' => $this->getRealObjectId()]);
	$this->lock = $lock;
	$this->setAsLoadedAttribute('lock');

	if ($lock && $lock->shouldProcessAutoUnlock())
	{
		$this->unlock(SystemUser::SYSTEM_USER_ID);
		$this->lock = null;
	}

	return $this->lock;
}