4 files changed, 394 insertions, 233 deletions
diff --git a/phpBB/includes/acm/acm_apc.php b/phpBB/includes/acm/acm_apc.php
index e4c4b79de3..e0714b1f0a 100644
--- a/phpBB/includes/acm/acm_apc.php
+++ b/phpBB/includes/acm/acm_apc.php
@@ -1,10 +1,10 @@
 <?php
-/** 
+/**
 *
 * @package acm
 * @version $Id$
-* @copyright (c) 2005 phpBB Group 
-* @license http://opensource.org/licenses/gpl-license.php GNU Public License 
+* @copyright (c) 2009 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
 *
 */
 
@@ -17,32 +17,35 @@ if (!defined('IN_PHPBB'))
 }
 
 /**
-* ACM APC Based Caching
+* ACM File Based Caching
 * @package acm
 */
 class acm
 {
-	private $vars = array();
-	private $is_modified = false;
+	var $vars = array();
+	var $is_modified = false;
 
-	public $sql_rowset = array();
-	public $cache_dir = '';
+	var $sql_rowset = array();
+	var $sql_row_pointer = array();
+	var $cache_dir = '';
 
 	/**
 	* Set cache path
 	*/
-	function __construct()
+	function acm()
 	{
-		$this->cache_dir = PHPBB_ROOT_PATH . 'cache/';
+		$this->cache_dir = $phpbb_root_path . 'cache/';
 	}
 
 	/**
 	* Load global cache
 	*/
-	private function load()
+	function load()
 	{
 		// grab the global cache
-		if ($this->vars = apc_fetch('global'))
+		$this->vars = apc_fetch('global');
+
+		if ($this->vars !== false)
 		{
 			return true;
 		}
@@ -53,20 +56,22 @@ class acm
 	/**
 	* Unload cache object
 	*/
-	public function unload()
+	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
 	*/
-	private function save()
+	function save()
 	{
 		if (!$this->is_modified)
 		{
@@ -81,7 +86,7 @@ class acm
 	/**
 	* Tidy cache
 	*/
-	public function tidy()
+	function tidy()
 	{
 		// cache has auto GC, no need to have any code here :)
 
@@ -91,28 +96,29 @@ class acm
 	/**
 	* Get saved cache object
 	*/
-	public function get($var_name)
+	function get($var_name)
 	{
-		if ($var_name[0] === '_')
+		if ($var_name[0] == '_')
 		{
+			if (!$this->_exists($var_name))
+			{
+				return false;
+			}
+
 			return apc_fetch($var_name);
 		}
 		else
 		{
-			if (!sizeof($this->vars))
-			{
-				$this->load();
-			}
-			return (isset($this->vars[$var_name])) ? $this->vars[$var_name] : false;
+			return ($this->_exists($var_name)) ? $this->vars[$var_name] : false;
 		}
 	}
 
 	/**
 	* Put data into cache
 	*/
-	public function put($var_name, $var, $ttl = 31536000)
+	function put($var_name, $var, $ttl = 31536000)
 	{
-		if ($var_name[0] === '_')
+		if ($var_name[0] == '_')
 		{
 			apc_store($var_name, $var, $ttl);
 		}
@@ -126,7 +132,7 @@ class acm
 	/**
 	* Purge cache data
 	*/
-	public function purge()
+	function purge()
 	{
 		// Purge all phpbb cache files
 		$dir = @opendir($this->cache_dir);
@@ -143,7 +149,7 @@ class acm
 				continue;
 			}
 
-			@unlink($this->cache_dir . $entry);
+			$this->remove_file($this->cache_dir . $entry);
 		}
 		closedir($dir);
 
@@ -151,10 +157,11 @@ class acm
 
 		unset($this->vars);
 		unset($this->sql_rowset);
+		unset($this->sql_row_pointer);
 
 		$this->vars = array();
-		$this->var_expires = array();
 		$this->sql_rowset = array();
+		$this->sql_row_pointer = array();
 
 		$this->is_modified = false;
 	}
@@ -162,9 +169,9 @@ class acm
 	/**
 	* Destroy cache data
 	*/
-	public function destroy($var_name, $table = '')
+	function destroy($var_name, $table = '')
 	{
-		if ($var_name === 'sql' && !empty($table))
+		if ($var_name == 'sql' && !empty($table))
 		{
 			if (!is_array($table))
 			{
@@ -175,6 +182,7 @@ class acm
 			{
 				// gives us the md5s that we want
 				$temp = apc_fetch('sql_' . $table_name);
+
 				if ($temp === false)
 				{
 					continue;
@@ -193,7 +201,12 @@ class acm
 			return;
 		}
 
-		if ($var_name[0] === '_')
+		if (!$this->_exists($var_name))
+		{
+			return;
+		}
+
+		if ($var_name[0] == '_')
 		{
 			apc_delete($var_name);
 		}
@@ -208,9 +221,29 @@ class acm
 	}
 
 	/**
+	* Check if a given cache entry exist
+	*/
+	function _exists($var_name)
+	{
+		if ($var_name[0] == '_')
+		{
+			return true;
+		}
+		else
+		{
+			if (!sizeof($this->vars))
+			{
+				$this->load();
+			}
+
+			return isset($this->vars[$var_name]);
+		}
+	}
+
+	/**
 	* Load cached sql query
 	*/
-	public function sql_load($query)
+	function sql_load($query)
 	{
 		// Remove extra spaces and tabs
 		$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
@@ -224,6 +257,7 @@ class acm
 		}
 
 		$this->sql_rowset[$query_id] = $temp;
+		$this->sql_row_pointer[$query_id] = 0;
 
 		return $query_id;
 	}
@@ -231,25 +265,15 @@ class acm
 	/**
 	* Save sql query
 	*/
-	public function sql_save($query, &$query_result, $ttl)
+	function sql_save($query, &$query_result, $ttl)
 	{
-		global $db;
-
 		// Remove extra spaces and tabs
 		$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
 
-		// determine which tables this query belongs to:
-
-		// grab all the FROM tables, avoid getting a LEFT JOIN
-		preg_match('/FROM \(?(\w+(?: (?!LEFT JOIN)\w+)?(?:, ?\w+(?: (?!LEFT JOIN)\w+)?)*)\)?/', $query, $regs);
+		// determine which tables this query belongs to
+		preg_match('/FROM \\(?(\\w+(?: \\w+)?(?:, ?\\w+(?: \\w+)?)*)\\)?/', $query, $regs);
 		$tables = array_map('trim', explode(',', $regs[1]));
 
-		// now get the LEFT JOIN
-		preg_match_all('/LEFT JOIN\s+(\w+)(?: \w+)?/', $query, $result, PREG_PATTERN_ORDER);
-		$tables = array_merge($tables, $result[1]);
-
-		$query_hash = md5($query);
-
 		foreach ($tables as $table_name)
 		{
 			if (($pos = strpos($table_name, ' ')) !== false)
@@ -262,13 +286,14 @@ class acm
 			{
 				$temp = array();
 			}
-			$temp[$query_hash] = true;
+			$temp[md5($query)] = true;
 			apc_store('sql_' . $table_name, $temp, $ttl);
 		}
 
 		// 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))
 		{
@@ -276,35 +301,63 @@ class acm
 		}
 		$db->sql_freeresult($query_result);
 
-		apc_store('sql_' . $query_hash, $this->sql_rowset[$query_id], $ttl);
+		apc_store('sql_' . md5($query), $this->sql_rowset[$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[$query_id]);
+	}
+
+	/**
 	* Fetch row from cache (database)
 	*/
-	public function sql_fetchrow($query_id)
+	function sql_fetchrow($query_id)
 	{
-		list(, $row) = each($this->sql_rowset[$query_id]);
+		if ($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 ($row !== NULL) ? $row : false;
+		return false;
 	}
 
 	/**
 	* Fetch a field from the current row of a cached database result (database)
 	*/
-	public function sql_fetchfield($query_id, $field)
+	function sql_fetchfield($query_id, $field)
 	{
-		$row = current($this->sql_rowset[$query_id]);
+		if ($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 ($row !== false && isset($row[$field])) ? $row[$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)
 	*/
-	public function sql_freeresult($query_id)
+	function sql_freeresult($query_id)
 	{
 		if (!isset($this->sql_rowset[$query_id]))
 		{
@@ -312,9 +365,24 @@ class acm
 		}
 
 		unset($this->sql_rowset[$query_id]);
+		unset($this->sql_row_pointer[$query_id]);
 
 		return true;
 	}
+
+	/**
+	* Removes/unlinks file
+	*/
+	function remove_file($filename, $check = false)
+	{
+		if ($check && !@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);
+	}
 }
 
 ?>
 \ No newline at end of file
diff --git a/phpBB/includes/acm/acm_eaccelerator.php b/phpBB/includes/acm/acm_eaccelerator.php
index 00d08f70d3..a1bc59d803 100644
--- a/phpBB/includes/acm/acm_eaccelerator.php
+++ b/phpBB/includes/acm/acm_eaccelerator.php
@@ -1,72 +1,69 @@
 <?php
-/** 
+/**
 *
 * @package acm
 * @version $Id$
-* @copyright (c) 2005 phpBB Group 
-* @license http://opensource.org/licenses/gpl-license.php GNU Public License 
+* @copyright (c) 2005 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
 *
 */
 
 /**
-* @ignore
-*/
-if (!defined('IN_PHPBB'))
-{
-	exit;
-}
-
-/**
-* ACM eAccelerator Based Caching
+* ACM Memcache Based Caching
 * @package acm
 */
 class acm
 {
-	private $vars = array();
-	private $is_modified = false;
+	var $vars = array();
+	var $is_modified = false;
 
-	public $sql_rowset = array();
-	public $cache_dir = '';
+	var $sql_rowset = array();
+	var $sql_row_pointer = array();
+	var $cache_dir = '';
 
 	/**
 	* Set cache path
 	*/
-	function __construct()
+	function acm()
 	{
-		$this->cache_dir = PHPBB_ROOT_PATH . 'cache/';
+		$this->cache_dir = $phpbb_root_path . 'cache/';
 	}
 
 	/**
 	* Load global cache
 	*/
-	private function load()
+	function load()
 	{
 		// grab the global cache
-		if ($this->vars = eaccelerator_get('global'))
+		$temp = eaccelerator_get('global');
+
+		if ($temp !== null)
 		{
-			return true;
+			$this->vars = $temp;
+		}
+		else
+		{
+			return false;
 		}
 
-		return false;
+		return true;
 	}
 
 	/**
 	* Unload cache object
 	*/
-	public function unload()
+	function unload()
 	{
 		$this->save();
 		unset($this->vars);
 		unset($this->sql_rowset);
-
-		$this->vars = array();
-		$this->sql_rowset = array();
+		unset($this->sql_row_pointer);
 	}
 
 	/**
 	* Save modified objects
 	*/
-	private function save()
+	function save()
 	{
 		if (!$this->is_modified)
 		{
@@ -81,7 +78,7 @@ class acm
 	/**
 	* Tidy cache
 	*/
-	public function tidy()
+	function tidy()
 	{
 		eaccelerator_gc();
 
@@ -91,9 +88,9 @@ class acm
 	/**
 	* Get saved cache object
 	*/
-	public function get($var_name)
+	function get($var_name)
 	{
-		if ($var_name[0] === '_')
+		if ($var_name[0] == '_')
 		{
 			$temp = eaccelerator_get($var_name);
 
@@ -119,9 +116,9 @@ class acm
 	/**
 	* Put data into cache
 	*/
-	public function put($var_name, $var, $ttl = 31536000)
+	function put($var_name, $var, $ttl = 31536000)
 	{
-		if ($var_name[0] === '_')
+		if ($var_name[0] == '_')
 		{
 			eaccelerator_put($var_name, $var, $ttl);
 		}
@@ -135,7 +132,7 @@ class acm
 	/**
 	* Purge cache data
 	*/
-	public function purge()
+	function purge()
 	{
 		// Purge all phpbb cache files
 		$dir = @opendir($this->cache_dir);
@@ -163,10 +160,7 @@ class acm
 
 		unset($this->vars);
 		unset($this->sql_rowset);
-
-		$this->vars = array();
-		$this->var_expires = array();
-		$this->sql_rowset = array();
+		unset($this->sql_row_pointer);
 
 		$this->is_modified = false;
 	}
@@ -174,9 +168,9 @@ class acm
 	/**
 	* Destroy cache data
 	*/
-	public function destroy($var_name, $table = '')
+	function destroy($var_name, $table = '')
 	{
-		if ($var_name === 'sql' && !empty($table))
+		if ($var_name == 'sql' && !empty($table))
 		{
 			if (!is_array($table))
 			{
@@ -209,7 +203,7 @@ class acm
 			return;
 		}
 
-		if ($var_name[0] === '_')
+		if ($var_name[0] == '_')
 		{
 			eaccelerator_rm($var_name);
 		}
@@ -226,7 +220,7 @@ class acm
 	/**
 	* Load cached sql query
 	*/
-	public function sql_load($query)
+	function sql_load($query)
 	{
 		// Remove extra spaces and tabs
 		$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
@@ -241,31 +235,23 @@ class acm
 
 		$this->sql_rowset[$query_id] = $temp;
 
+		$this->sql_row_pointer[$query_id] = 0;
+
 		return $query_id;
 	}
 
 	/**
 	* Save sql query
 	*/
-	public function sql_save($query, &$query_result, $ttl)
+	function sql_save($query, &$query_result, $ttl)
 	{
-		global $db;
-
 		// Remove extra spaces and tabs
 		$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
 
-		// determine which tables this query belongs to:
-
-		// grab all the FROM tables, avoid getting a LEFT JOIN
-		preg_match('/FROM \(?(\w+(?: (?!LEFT JOIN)\w+)?(?:, ?\w+(?: (?!LEFT JOIN)\w+)?)*)\)?/', $query, $regs);
+		// determine which tables this query belongs to
+		preg_match('/FROM \\(?(\\w+(?: \\w+)?(?:, ?\\w+(?: \\w+)?)*)\\)?/', $query, $regs);
 		$tables = array_map('trim', explode(',', $regs[1]));
 
-		// now get the LEFT JOIN
-		preg_match_all('/LEFT JOIN\s+(\w+)(?: \w+)?/', $query, $result, PREG_PATTERN_ORDER);
-		$tables = array_merge($tables, $result[1]);
-
-		$query_hash = md5($query);
-
 		foreach ($tables as $table_name)
 		{
 			if (($pos = strpos($table_name, ' ')) !== false)
@@ -278,13 +264,14 @@ class acm
 			{
 				$temp = array();
 			}
-			$temp[$query_hash] = true;
+			$temp[md5($query)] = true;
 			eaccelerator_put('sql_' . $table_name, $temp, $ttl);
 		}
 
 		// 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))
 		{
@@ -292,35 +279,63 @@ class acm
 		}
 		$db->sql_freeresult($query_result);
 
-		eaccelerator_put('sql_' . $query_hash, $this->sql_rowset[$query_id], $ttl);
+		eaccelerator_put('sql_' . md5($query), $this->sql_rowset[$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[$query_id]);
+	}
+
+	/**
 	* Fetch row from cache (database)
 	*/
-	public function sql_fetchrow($query_id)
+	function sql_fetchrow($query_id)
 	{
-		list(, $row) = each($this->sql_rowset[$query_id]);
+		if ($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 ($row !== NULL) ? $row : false;
+		return false;
 	}
 
 	/**
 	* Fetch a field from the current row of a cached database result (database)
 	*/
-	public function sql_fetchfield($query_id, $field)
+	function sql_fetchfield($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)
 	{
-		$row = current($this->sql_rowset[$query_id]);
+		if ($rownum >= sizeof($this->sql_rowset[$query_id]))
+		{
+			return false;
+		}
 
-		return ($row !== false && isset($row[$field])) ? $row[$field] : false;
+		$this->sql_row_pointer[$query_id] = $rownum;
+		return true;
 	}
 
 	/**
 	* Free memory used for a cached database result (database)
 	*/
-	public function sql_freeresult($query_id)
+	function sql_freeresult($query_id)
 	{
 		if (!isset($this->sql_rowset[$query_id]))
 		{
@@ -328,6 +343,7 @@ class acm
 		}
 
 		unset($this->sql_rowset[$query_id]);
+		unset($this->sql_row_pointer[$query_id]);
 
 		return true;
 	}
diff --git a/phpBB/includes/acm/acm_memcache.php b/phpBB/includes/acm/acm_memcache.php
index bbb556f173..a89657b04e 100644
--- a/phpBB/includes/acm/acm_memcache.php
+++ b/phpBB/includes/acm/acm_memcache.php
@@ -1,10 +1,10 @@
 <?php
-/** 
+/**
 *
 * @package acm
 * @version $Id$
-* @copyright (c) 2005 phpBB Group 
-* @license http://opensource.org/licenses/gpl-license.php GNU Public License 
+* @copyright (c) 2005 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
 *
 */
 
@@ -17,33 +17,38 @@ if (!defined('IN_PHPBB'))
 }
 
 /**
-* ACM Memcache Based Caching
+* ACM File Based Caching
 * @package acm
 */
 class acm
 {
-	private $vars = array();
-	private $is_modified = false;
+	var $vars = array();
+	var $is_modified = false;
+
+	var $sql_rowset = array();
+	var $sql_row_pointer = array();
+	var $cache_dir = '';
 
-	public $sql_rowset = array();
-	public $cache_dir = '';
-	private $memcache;
+	var $memcache;
 
 	/**
 	* Set cache path
 	*/
-	function __construct()
+	function acm()
 	{
+		$this->cache_dir = $phpbb_root_path . 'cache/';
 		$this->memcache = memcache_connect('localhost', 11211);
 	}
 
 	/**
 	* Load global cache
 	*/
-	private function load()
+	function load()
 	{
 		// grab the global cache
-		if ($this->vars = memcache_get($this->memcache, 'global'))
+		$this->vars = memcache_get($this->memcache, 'global');
+
+		if ($this->vars !== false)
 		{
 			return true;
 		}
@@ -54,20 +59,22 @@ class acm
 	/**
 	* Unload cache object
 	*/
-	public function unload()
+	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
 	*/
-	private function save()
+	function save()
 	{
 		if (!$this->is_modified)
 		{
@@ -82,7 +89,7 @@ class acm
 	/**
 	* Tidy cache
 	*/
-	public function tidy()
+	function tidy()
 	{
 		// cache has auto GC, no need to have any code here :)
 
@@ -92,28 +99,29 @@ class acm
 	/**
 	* Get saved cache object
 	*/
-	public function get($var_name)
+	function get($var_name)
 	{
-		if ($var_name[0] === '_')
+		if ($var_name[0] == '_')
 		{
+			if (!$this->_exists($var_name))
+			{
+				return false;
+			}
+
 			return memcache_get($this->memcache, $var_name);
 		}
 		else
 		{
-			if (!sizeof($this->vars))
-			{
-				$this->load();
-			}
-			return (isset($this->vars[$var_name])) ? $this->vars[$var_name] : false;
+			return ($this->_exists($var_name)) ? $this->vars[$var_name] : false;
 		}
 	}
 
 	/**
 	* Put data into cache
 	*/
-	public function put($var_name, $var, $ttl = 31536000)
+	function put($var_name, $var, $ttl = 2592000)
 	{
-		if ($var_name[0] === '_')
+		if ($var_name[0] == '_')
 		{
 			memcache_set($this->memcache, $var_name, $var, 0, $ttl);
 		}
@@ -127,7 +135,7 @@ class acm
 	/**
 	* Purge cache data
 	*/
-	public function purge()
+	function purge()
 	{
 		// Purge all phpbb cache files
 		$dir = @opendir($this->cache_dir);
@@ -144,7 +152,7 @@ class acm
 				continue;
 			}
 
-			@unlink($this->cache_dir . $entry);
+			$this->remove_file($this->cache_dir . $entry);
 		}
 		closedir($dir);
 
@@ -152,20 +160,22 @@ class acm
 
 		unset($this->vars);
 		unset($this->sql_rowset);
+		unset($this->sql_row_pointer);
 
 		$this->vars = array();
-		$this->var_expires = array();
 		$this->sql_rowset = array();
+		$this->sql_row_pointer = array();
 
 		$this->is_modified = false;
 	}
 
+
 	/**
 	* Destroy cache data
 	*/
-	public function destroy($var_name, $table = '')
+	function destroy($var_name, $table = '')
 	{
-		if ($var_name === 'sql' && !empty($table))
+		if ($var_name == 'sql' && !empty($table))
 		{
 			if (!is_array($table))
 			{
@@ -176,6 +186,7 @@ class acm
 			{
 				// gives us the md5s that we want
 				$temp = memcache_get($this->memcache, 'sql_' . $table_name);
+
 				if ($temp === false)
 				{
 					continue;
@@ -194,7 +205,12 @@ class acm
 			return;
 		}
 
-		if ($var_name[0] === '_')
+		if (!$this->_exists($var_name))
+		{
+			return;
+		}
+
+		if ($var_name[0] == '_')
 		{
 			memcache_delete($this->memcache, $var_name);
 		}
@@ -209,9 +225,29 @@ class acm
 	}
 
 	/**
+	* Check if a given cache entry exist
+	*/
+	function _exists($var_name)
+	{
+		if ($var_name[0] == '_')
+		{
+			return true;
+		}
+		else
+		{
+			if (!sizeof($this->vars))
+			{
+				$this->load();
+			}
+
+			return isset($this->vars[$var_name]);
+		}
+	}
+
+	/**
 	* Load cached sql query
 	*/
-	public function sql_load($query)
+	function sql_load($query)
 	{
 		// Remove extra spaces and tabs
 		$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
@@ -225,7 +261,7 @@ class acm
 		}
 
 		$this->sql_rowset[$query_id] = $temp;
-
+		$this->sql_row_pointer[$query_id] = 0;
 
 		return $query_id;
 	}
@@ -233,25 +269,15 @@ class acm
 	/**
 	* Save sql query
 	*/
-	public function sql_save($query, &$query_result, $ttl)
+	function sql_save($query, &$query_result, $ttl)
 	{
-		global $db;
-
 		// Remove extra spaces and tabs
 		$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
 
-		// determine which tables this query belongs to:
-
-		// grab all the FROM tables, avoid getting a LEFT JOIN
-		preg_match('/FROM \(?(\w+(?: (?!LEFT JOIN)\w+)?(?:, ?\w+(?: (?!LEFT JOIN)\w+)?)*)\)?/', $query, $regs);
+		// determine which tables this query belongs to
+		preg_match('/FROM \\(?(\\w+(?: \\w+)?(?:, ?\\w+(?: \\w+)?)*)\\)?/', $query, $regs);
 		$tables = array_map('trim', explode(',', $regs[1]));
 
-		// now get the LEFT JOIN
-		preg_match_all('/LEFT JOIN\s+(\w+)(?: \w+)?/', $query, $result, PREG_PATTERN_ORDER);
-		$tables = array_merge($tables, $result[1]);
-
-		$query_hash = md5($query);
-
 		foreach ($tables as $table_name)
 		{
 			if (($pos = strpos($table_name, ' ')) !== false)
@@ -264,13 +290,14 @@ class acm
 			{
 				$temp = array();
 			}
-			$temp[$query_hash] = true;
+			$temp[md5($query)] = true;
 			memcache_set($this->memcache, 'sql_' . $table_name, $temp, 0, $ttl);
 		}
 
 		// 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))
 		{
@@ -278,35 +305,63 @@ class acm
 		}
 		$db->sql_freeresult($query_result);
 
-		memcache_set($this->memcache, 'sql_' . $query_hash, $this->sql_rowset[$query_id], 0, $ttl);
+		memcache_set($this->memcache, 'sql_' . md5($query), $this->sql_rowset[$query_id], 0, $ttl);
 
 		$query_result = $query_id;
 	}
 
 	/**
+	* Ceck if a given sql query exist in cache
+	*/
+	function sql_exists($query_id)
+	{
+		return isset($this->sql_rowset[$query_id]);
+	}
+
+	/**
 	* Fetch row from cache (database)
 	*/
-	public function sql_fetchrow($query_id)
+	function sql_fetchrow($query_id)
 	{
-		list(, $row) = each($this->sql_rowset[$query_id]);
+		if ($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 ($row !== NULL) ? $row : false;
+		return false;
 	}
 
 	/**
 	* Fetch a field from the current row of a cached database result (database)
 	*/
-	public function sql_fetchfield($query_id, $field)
+	function sql_fetchfield($query_id, $field)
 	{
-		$row = current($this->sql_rowset[$query_id]);
+		if ($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 ($row !== false && isset($row[$field])) ? $row[$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)
 	*/
-	public function sql_freeresult($query_id)
+	function sql_freeresult($query_id)
 	{
 		if (!isset($this->sql_rowset[$query_id]))
 		{
@@ -314,9 +369,24 @@ class acm
 		}
 
 		unset($this->sql_rowset[$query_id]);
+		unset($this->sql_row_pointer[$query_id]);
 
 		return true;
 	}
+
+	/**
+	* Removes/unlinks file
+	*/
+	function remove_file($filename, $check = false)
+	{
+		if ($check && !@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);
+	}
 }
 
 ?>
 \ No newline at end of file
diff --git a/phpBB/includes/acm/acm_xcache.php b/phpBB/includes/acm/acm_xcache.php
index 38db4d27d8..9531f5e03d 100644
--- a/phpBB/includes/acm/acm_xcache.php
+++ b/phpBB/includes/acm/acm_xcache.php
@@ -1,45 +1,38 @@
 <?php
-/** 
+/**
 *
 * @package acm
 * @version $Id$
-* @copyright (c) 2005 phpBB Group 
-* @license http://opensource.org/licenses/gpl-license.php GNU Public License 
+* @copyright (c) 2005 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
 *
 */
 
 /**
-* @ignore
-*/
-if (!defined('IN_PHPBB'))
-{
-	exit;
-}
-
-/**
 * ACM XCache Based Caching
 * @package acm
 */
 class acm
 {
-	private $vars = array();
-	private $is_modified = false;
+	var $vars = array();
+	var $is_modified = false;
 
-	public $sql_rowset = array();
-	public $cache_dir = '';
+	var $sql_rowset = array();
+	var $sql_row_pointer = array();
+	var $cache_dir = '';
 
 	/**
 	* Set cache path
 	*/
-	function __construct()
+	function acm()
 	{
-		$this->cache_dir = PHPBB_ROOT_PATH . 'cache/';
+		$this->cache_dir = $phpbb_root_path . 'cache/';
 	}
 
 	/**
 	* Load global cache
 	*/
-	private function load()
+	function load()
 	{
 		// grab the global cache
 		if (xcache_isset('global'))
@@ -54,20 +47,18 @@ class acm
 	/**
 	* Unload cache object
 	*/
-	public function unload()
+	function unload()
 	{
 		$this->save();
 		unset($this->vars);
 		unset($this->sql_rowset);
-
-		$this->vars = array();
-		$this->sql_rowset = array();
+		unset($this->sql_row_pointer);
 	}
 
 	/**
 	* Save modified objects
 	*/
-	private function save()
+	function save()
 	{
 		if (!$this->is_modified)
 		{
@@ -82,7 +73,7 @@ class acm
 	/**
 	* Tidy cache
 	*/
-	public function tidy()
+	function tidy()
 	{
 		// cache has auto GC, no need to have any code here :)
 
@@ -92,9 +83,9 @@ class acm
 	/**
 	* Get saved cache object
 	*/
-	public function get($var_name)
+	function get($var_name)
 	{
-		if ($var_name[0] === '_')
+		if ($var_name[0] == '_')
 		{
 			return (xcache_isset($var_name)) ? xcache_get($var_name) : false;
 		}
@@ -111,9 +102,9 @@ class acm
 	/**
 	* Put data into cache
 	*/
-	public function put($var_name, $var, $ttl = 31536000)
+	function put($var_name, $var, $ttl = 31536000)
 	{
-		if ($var_name[0] === '_')
+		if ($var_name[0] == '_')
 		{
 			xcache_set($var_name, $var, $ttl);
 		}
@@ -127,7 +118,7 @@ class acm
 	/**
 	* Purge cache data
 	*/
-	public function purge()
+	function purge()
 	{
 		// Purge all phpbb cache files
 		$dir = @opendir($this->cache_dir);
@@ -156,10 +147,7 @@ class acm
 
 		unset($this->vars);
 		unset($this->sql_rowset);
-
-		$this->vars = array();
-		$this->var_expires = array();
-		$this->sql_rowset = array();
+		unset($this->sql_row_pointer);
 
 		$this->is_modified = false;
 	}
@@ -167,9 +155,9 @@ class acm
 	/**
 	* Destroy cache data
 	*/
-	public function destroy($var_name, $table = '')
+	function destroy($var_name, $table = '')
 	{
-		if ($var_name === 'sql' && !empty($table))
+		if ($var_name == 'sql' && !empty($table))
 		{
 			if (!is_array($table))
 			{
@@ -198,7 +186,7 @@ class acm
 			return;
 		}
 
-		if ($var_name[0] === '_')
+		if ($var_name[0] == '_')
 		{
 			xcache_unset($var_name);
 		}
@@ -215,21 +203,20 @@ class acm
 	/**
 	* Load cached sql query
 	*/
-	public function sql_load($query)
+	function sql_load($query)
 	{
 		// Remove extra spaces and tabs
 		$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
 		$query_id = sizeof($this->sql_rowset);
 
-		$query_hash = md5($query);
-
-		if (!xcache_isset('sql_' . $query_hash))
+		if (!xcache_isset('sql_' . md5($query)))
 		{
 			return false;
 		}
 
-		$this->sql_rowset[$query_id] = xcache_get('sql_' . $query_hash);
+		$this->sql_rowset[$query_id] = xcache_get('sql_' . md5($query));
 
+		$this->sql_row_pointer[$query_id] = 0;
 
 		return $query_id;
 	}
@@ -237,25 +224,15 @@ class acm
 	/**
 	* Save sql query
 	*/
-	public function sql_save($query, &$query_result, $ttl)
+	function sql_save($query, &$query_result, $ttl)
 	{
-		global $db;
-
 		// Remove extra spaces and tabs
 		$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
 
-		// determine which tables this query belongs to:
-
-		// grab all the FROM tables, avoid getting a LEFT JOIN
-		preg_match('/FROM \(?(\w+(?: (?!LEFT JOIN)\w+)?(?:, ?\w+(?: (?!LEFT JOIN)\w+)?)*)\)?/', $query, $regs);
+		// determine which tables this query belongs to
+		preg_match('/FROM \\(?(\\w+(?: \\w+)?(?:, ?\\w+(?: \\w+)?)*)\\)?/', $query, $regs);
 		$tables = array_map('trim', explode(',', $regs[1]));
 
-		// now get the LEFT JOIN
-		preg_match_all('/LEFT JOIN\s+(\w+)(?: \w+)?/', $query, $result, PREG_PATTERN_ORDER);
-		$tables = array_merge($tables, $result[1]);
-
-		$query_hash = md5($query);
-
 		foreach ($tables as $table_name)
 		{
 			if (($pos = strpos($table_name, ' ')) !== false)
@@ -271,13 +248,14 @@ class acm
 			{
 				$temp = array();
 			}
-			$temp[$query_hash] = true;
+			$temp[md5($query)] = true;
 			xcache_set('sql_' . $table_name, $temp, $ttl);
 		}
 
 		// 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))
 		{
@@ -285,35 +263,63 @@ class acm
 		}
 		$db->sql_freeresult($query_result);
 
-		xcache_set('sql_' . $query_hash, $this->sql_rowset[$query_id], $ttl);
+		xcache_set('sql_' . md5($query), $this->sql_rowset[$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[$query_id]);
+	}
+
+	/**
 	* Fetch row from cache (database)
 	*/
-	public function sql_fetchrow($query_id)
+	function sql_fetchrow($query_id)
 	{
-		list(, $row) = each($this->sql_rowset[$query_id]);
+		if ($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 ($row !== NULL) ? $row : false;
+		return false;
 	}
 
 	/**
 	* Fetch a field from the current row of a cached database result (database)
 	*/
-	public function sql_fetchfield($query_id, $field)
+	function sql_fetchfield($query_id, $field)
 	{
-		$row = current($this->sql_rowset[$query_id]);
+		if ($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;
+	}
 
-		return ($row !== false && isset($row[$field])) ? $row[$field] : 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)
 	*/
-	public function sql_freeresult($query_id)
+	function sql_freeresult($query_id)
 	{
 		if (!isset($this->sql_rowset[$query_id]))
 		{
@@ -321,6 +327,7 @@ class acm
 		}
 
 		unset($this->sql_rowset[$query_id]);
+		unset($this->sql_row_pointer[$query_id]);
 
 		return true;
 	}