<?php
/**
*
* @package acm
* @version $Id$
* @copyright (c) 2005 phpBB Group
* @license http://opensource.org/licenses/gpl-license.php GNU Public License
*
*/
/**
* @ignore
*/
if (!defined('IN_PHPBB'))
{
exit;
}
/**
* ACM Abstract Memory Class
* @package acm
*/
class acm_memory
{
var $key_prefix;
var $vars = array();
var $is_modified = false;
var $sql_rowset = array();
var $sql_row_pointer = array();
var $cache_dir = '';
/**
* Set cache path
*/
function acm_memory()
{
global $phpbb_root_path, $dbname, $table_prefix;
$this->cache_dir = $phpbb_root_path . 'cache/';
$this->key_prefix = substr(md5($dbname . $table_prefix), 0, 8) . '_';
if (!isset($this->extension) || !extension_loaded($this->extension))
{
global $acm_type;
trigger_error("Could not find required extension [{$this->extension}] for the ACM module $acm_type.", E_USER_ERROR);
}
if (isset($this->function) && !function_exists($this->function))
{
global $acm_type;
trigger_error("The required function [{$this->function}] is not available for the ACM module $acm_type.", E_USER_ERROR);
}
}
/**
* Load global cache
*/
function load()
{
// grab the global cache
$this->vars = $this->_read('global');
if ($this->vars !== false)
{
return true;
}
return false;
}
/**
* Unload cache object
*/
function unload()
{
$this->save();
unset($this->vars);
unset($this->sql_rowset);
unset($this->sql_row_pointer);
$this->vars = array();
$this->sql_rowset = array();
$this->sql_row_pointer = array();
}
/**
* Save modified objects
*/
function save()
{
if (!$this->is_modified)
{
return;
}
$this->_write('global', $this->vars, 2592000);
$this->is_modified = false;
}
/**
* Tidy cache
*/
function tidy()
{
// cache has auto GC, no need to have any code here :)
set_config('cache_last_gc', time(), true);
}
/**
* Get saved cache object
*/
function get($var_name)
{
if ($var_name[0] == '_')
{
if (!$this->_exists($var_name))
{
return false;
}
return $this->_read($var_name);
}
else
{
return ($this->_exists($var_name)) ? $this->vars[$var_name] : false;
}
}
/**
* Put data into cache
*/
function put($var_name, $var, $ttl = 2592000)
{
if ($var_name[0] == '_')
{
$this->_write($var_name, $var, $ttl);
}
else
{
$this->vars[$var_name] = $var;
$this->is_modified = true;
}
}
/**
* Purge cache data
*/
function purge()
{
// Purge all phpbb cache files
$dir = @opendir($this->cache_dir);
if (!$dir)
{
return;
}
while (($entry = readdir($dir)) !== false)
{
if (strpos($entry, 'sql_') !== 0 && strpos($entry, 'data_') !== 0 && strpos($entry, 'ctpl_') !== 0 && strpos($entry, 'tpl_') !== 0)
{
continue;
}
$this->remove_file($this->cache_dir . $entry);
}
closedir($dir);
unset($this->vars);
unset($this->sql_rowset);
unset($this->sql_row_pointer);
$this->vars = array();
$this->sql_rowset = array();
$this->sql_row_pointer = array();
$this->is_modified = false;
}
/**
* Destroy cache data
*/
function destroy($var_name, $table = '')
{
if ($var_name == 'sql' && !empty($table))
{
if (!is_array($table))
{
$table = array($table);
}
foreach ($table as $table_name)
{
// gives us the md5s that we want
$temp = $this->_read('sql_' . $table_name);
if ($temp === false)
{
continue;
}
// delete each query ref
foreach ($temp as $md5_id => $void)
{
$this->_delete('sql_' . $md5_id);
}
// delete the table ref
$this->_delete('sql_' . $table_name);
}
return;
}
if (!$this->_exists($var_name))
{
return;
}
if ($var_name[0] == '_')
{
$this->_delete($var_name);
}
else if (isset($this->vars[$var_name]))
{
$this->is_modified = true;
unset($this->vars[$var_name]);
// We save here to let the following cache hits succeed
$this->save();
}
}
/**
* Check if a given cache entry exist
*/
function _exists($var_name)
{
if ($var_name[0] == '_')
{
return $this->_isset($var_name);
}
else
{
if (!sizeof($this->vars))
{
$this->load();
}
return isset($this->vars[$var_name]);
}
}
/**
* Load cached sql query
*/
function sql_load($query)
{
// Remove extra spaces and tabs
$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
$query_id = sizeof($this->sql_rowset);
if (($result = $this->_read('sql_' . md5($query))) === false)
{
return false;
}
$this->sql_rowset[$query_id] = $result;
$this->sql_row_pointer[$query_id] = 0;
return $query_id;
}
/**
* Save sql query
*/
function sql_save($query, &$query_result, $ttl)
{
global $db;
// Remove extra spaces and tabs
$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
$hash = md5($query);
// determine which tables this query belongs to
// Some queries use backticks, namely the get_database_size() query
// don't check for conformity, the SQL would error and not reach here.
if (!preg_match('/FROM \\(?(`?\\w+`?(?: \\w+)?(?:, ?`?\\w+`?(?: \\w+)?)*)\\)?/', $query, $regs))
{
// Bail out if the match fails.
return;
}
$tables = array_map('trim', explode(',', $regs[1]));
foreach ($tables as $table_name)
{
// Remove backticks
$table_name = ($table_name[0] == '`') ? substr($table_name, 1, -1) : $table_name;
if (($pos = strpos($table_name, ' ')) !== false)
{
$table_name = substr($table_name, 0, $pos);
}
$temp = $this->_read('sql_' . $table_name);
if ($temp === false)
{
$temp = array();
}
$temp[$hash] = true;
// This must never expire
$this->_write('sql_' . $table_name, $temp, 0);
}
// store them in the right place
$query_id = sizeof($this->sql_rowset);
$this->sql_rowset[$query_id] = array();
$this->sql_row_pointer[$query_id] = 0;
while ($row = $db->sql_fetchrow($query_result))
{
$this->sql_rowset[$query_id][] = $row;
}
$db->sql_freeresult($query_result);
$this->_write('sql_' . $hash, $this->sql_rowset[$query_id], $ttl);
$query_result = $query_id;
}
/**
* Ceck if a given sql query exist in cache
*/
function sql_exists($query_id)
{
return isset($this->sql_rowset[$query_id]);
}
/**
* Fetch row from cache (database)
*/
function sql_fetchrow($query_id)
{
if ($this->sql_row_pointer[$query_id] < sizeof($this->sql_rowset[$query_id]))
{
return $this->sql_rowset[$query_id][$this->sql_row_pointer[$query_id]++];
}
return false;
}
/**
* Fetch a field from the current row of a cached database result (database)
*/
function sql_fetchfield($query_id, $field)
{
if ($this->sql_row_pointer[$query_id] < sizeof($this->sql_rowset[$query_id]))
{
return (isset($this->sql_rowset[$query_id][$this->sql_row_pointer[$query_id]][$field])) ? $this->sql_rowset[$query_id][$this->sql_row_pointer[$query_id]++][$field] : false;
}
return false;
}
/**
* Seek a specific row in an a cached database result (database)
*/
function sql_rowseek($rownum, $query_id)
{
if ($rownum >= sizeof($this->sql_rowset[$query_id]))
{
return false;
}
$this->sql_row_pointer[$query_id] = $rownum;
return true;
}
/**
* Free memory used for a cached database result (database)
*/
function sql_freeresult($query_id)
{
if (!isset($this->sql_rowset[$query_id]))
{
return false;
}
unset($this->sql_rowset[$query_id]);
unset($this->sql_row_pointer[$query_id]);
return true;
}
/**
* Removes/unlinks file
*/
function remove_file($filename, $check = false)
{
if (!function_exists('phpbb_is_writable'))
{
global $phpbb_root_path, $phpEx;
include($phpbb_root_path . 'includes/functions.' . $phpEx);
}
if ($check && !phpbb_is_writable($this->cache_dir))
{
// E_USER_ERROR - not using language entry - intended.
trigger_error('Unable to remove files within ' . $this->cache_dir . '. Please check directory permissions.', E_USER_ERROR);
}
return @unlink($filename);
}
/**
* Check if a cache var exists
*
* @access protected
* @param string $var Cache key
* @return bool True if it exists, otherwise false
*/
function _isset($var)
{
// Most caches don't need to check
return true;
}
}
?>