LockManager.php

<?php

class LockManager {
        public function injectSettings($settings) {
                $this->settings = $settings;
        }
        public function ... {
                if (file_exists(..)) {
                read_file($this->settings['pathToFileForLockedSiteInWebScope'];
                } else {
                        # fallback to something
                }
        }
}

Scripts.php

<?php

class Scripts {
        public function initializeLockManager(..) {
                $settings = $configurationManager->getConfiguration(\TYPO3\Flow\Configuration\ConfigurationManager::CONFIGURATION_TYPE_SETTINGS, 'TYPO3.Flow');
                $lockManager->injectSettings($settings)
        }
}