Still to come…
/**
* Update/serve a cached file
*
* @access public
* @return void
*/
function _display_cache(&$CFG, &$RTR)
{
// Start session
session_start();
// For validation messages, you want to bypass a cached form
if ($_SERVER['REQUEST_METHOD'] != 'GET') {
return FALSE;
}
// Cache URI's built with Centralzed Cache URI
//---------------------------------------------
$cacheuri = $this->get_cache_URI();
$uri = $cacheuri['uri'];
$cache_path = $cacheuri['path'];
$filepath = $cache_path.md5($uri);
if ( ! @file_exists($filepath))
{
return FALSE;
}
if ( ! $fp = @fopen($filepath, 'rb'))
{
return FALSE;
}
flock($fp, LOCK_SH);
$cache = '';
if (filesize($filepath) > 0)
{
$cache = fread($fp, filesize($filepath));
}
flock($fp, LOCK_UN);
fclose($fp);
// Quickly bypass the cache so no one sees '{cached::name}' in their pages,
// or so that a user will always bypass a 'logged out' cache.
$token = strpos($cache,'{cached::');
if ( FALSE !== ($data = $this->_get_from_session($CFG->item('cache_data_source'))) && is_array($data))
{
if ($token === FALSE)
{
return FALSE;
}
} elseif ($token !== FALSE)
{
return FALSE;
}
// Okay, so they must be returning as the same status -- back to cache...
/*
* Seperate headers from content.
* This is used to output cached headers. <josh@surber.us>
*/
list($headers, $cache) = explode("\n\n", $cache, 2);
/*
* Seperate each header, looking for timestamp
* The others are output as-is. <josh@surber.us>
*/
$headers = explode("\n", $headers);
foreach ($headers as $header) {
if (FALSE === strpos($header, 'X-CI-timestamp')) {
$this->set_header($header);
} else {
$timestamp = substr($header, 16);
// Has the file expired? If so we'll delete it.
if (time() >= trim($timestamp))
{
@unlink($filepath);
log_message('debug', "Cache file has expired. File deleted");
return FALSE;
}
}
}
// --------------------------------------------------------------------
// Display the cache
$this->_display($cache);
log_message('debug', "Cache file is current. Sending it to browser.");
log_message('debug', "Cache for ".$uri." loaded from ".$filepath);
return TRUE;
}