FileCache.inc.php

<?php
 
import('lib.pkp.classes.cache.GenericCache');
 
class FileCache extends GenericCache {
   var $filename;
 
   var $cache;
 
   function __construct($context, $cacheId, $fallback, $path) {
      parent::__construct($context, $cacheId, $fallback);
 
      $this->filename = $path . DIRECTORY_SEPARATOR . "fc-$context-" . str_replace('/', '.', $cacheId) . '.php';
 
      // Load the cache data if it exists.
      if (($fp = @fopen($this->filename, 'r')) !== false) {
         flock($fp, LOCK_SH);
         $this->cache = include($this->filename);
         flock($fp, LOCK_UN);
      } else {
         $this->cache = null;
      }
   }
 
   function flush() {
      unset($this->cache);
      $this->cache = null;
      if (function_exists('opcache_invalidate')) opcache_invalidate($this->filename, true);
      @unlink($this->filename);
   }
 
   function getCache($id) {
      if (!isset($this->cache)) return $this->cacheMiss;
      return (isset($this->cache[$id])?$this->cache[$id]:null);
   }
 
   function setCache($id, $value) {
      // Flush the cache; it will be regenerated on demand.
      $this->flush();
   }
 
   function setEntireCache($contents) {
      if (file_put_contents(
         $this->filename,
         '<?php return ' . var_export($contents, true) . ';',
         LOCK_EX
      ) !== false) {
         $umask = Config::getVar('files', 'umask');
         if ($umask) @chmod($this->filename, FILE_MODE_MASK & ~$umask);
      }
      $this->cache = $contents;
   }
 
   function getCacheTime() {
      $result = @filemtime($this->filename);
      if ($result === false) return null;
      return ((int) $result);
   }
 
   function &getContents() {
      if (!isset($this->cache)) {
         // Trigger a cache miss to load the cache.
         $this->get(null);
      }
      return $this->cache;
   }
}