<?php
/**
* Class Minify_Cache_APC
* @package Minify
*/
/**
* APC-based cache class for Minify
*
* <code>
* Minify::setCache(new Minify_Cache_APC());
* </code>
*
* @package Minify
* @author Chris Edwards
**/
class Minify_Cache_APC {
/**
* Create a Minify_Cache_APC object, to be passed to
* Minify::setCache().
*
*
* @param int $expire seconds until expiration (default = 0
* meaning the item will not get an expiration date)
*
* @return null
*/
public function __construct($expire = 0)
{
$this->_exp = $expire;
}
/**
* Write data to cache.
*
* @param string $id cache id
*
* @param string $data
*
* @return bool success
*/
public function store($id, $data)
{
return apc_store($id, "{$_SERVER['REQUEST_TIME']}|{$data}", $this->_exp);
}
/**
* Get the size of a cache entry
*
* @param string $id cache id
*
* @return int size in bytes
*/
public function getSize($id)
{
if (! $this->_fetch($id)) {
return false;
}
return (function_exists('mb_strlen') && ((int)ini_get('mbstring.func_overload') & 2))
? mb_strlen($this->_data, '8bit')
: strlen($this->_data);
}
/**
* Does a valid cache entry exist?
*
* @param string $id cache id
*
* @param int $srcMtime mtime of the original source file(s)
*
* @return bool exists
*/
public function isValid($id, $srcMtime)
{
return ($this->_fetch($id) && ($this->_lm >= $srcMtime));
}
/**
* Send the cached content to output
*
* @param string $id cache id
*/
public function display($id)
{
echo $this->_fetch($id)
? $this->_data
: '';
}
/**
* Fetch the cached content
*
* @param string $id cache id
*
* @return string
*/
public function fetch($id)
{
return $this->_fetch($id)
? $this->_data
: '';
}
private $_exp = null;
// cache of most recently fetched id
private $_lm = null;
private $_data = null;
private $_id = null;
/**
* Fetch data and timestamp from apc, store in instance
*
* @param string $id
*
* @return bool success
*/
private function _fetch($id)
{
if ($this->_id === $id) {
return true;
}
$ret = apc_fetch($id);
if (false === $ret) {
$this->_id = null;
return false;
}
list($this->_lm, $this->_data) = explode('|', $ret, 2);
$this->_id = $id;
return true;
}
}