-<?php
-/**
- * Cache utilities
- */
-
-/**
- * Purges all cached pages
- *
- * @param string $pageCacheDir page cache directory
- *
- * @return mixed an error string if the directory is missing
- */
-function purgeCachedPages($pageCacheDir)
-{
- if (! is_dir($pageCacheDir)) {
- $error = sprintf(t('Cannot purge %s: no directory'), $pageCacheDir);
- error_log($error);
- return $error;
- }
-
- array_map('unlink', glob($pageCacheDir.'/*.cache'));
-}
-
-/**
- * Invalidates caches when the database is changed or the user logs out.
- *
- * @param string $pageCacheDir page cache directory
- */
-function invalidateCaches($pageCacheDir)
-{
- // Purge cache attached to session.
- if (isset($_SESSION['tags'])) {
- unset($_SESSION['tags']);
- }
-
- // Purge page cache shared by sessions.
- purgeCachedPages($pageCacheDir);
-}