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diff --git a/app/lib/Cache.php b/app/lib/Cache.php
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+<?php
+/**

+* This library is free software; you can redistribute it and/or modify

+* it under the terms of the GNU General Public License as published by

+* the Free Software Foundation; either version 2 of the License, or

+* (at your option) any later version.

+*

+* This library is distributed in the hope that it will be useful,

+* but WITHOUT ANY WARRANTY; without even the implied warranty of

+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+* GNU General Public License for more details.

+*

+* You should have received a copy of the GNU General Public License

+* along with this software; if not, write to the Free Software

+* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

+* 

+* © Copyright 2005 Richard Heyes

+*/
+
+/**
+* Caching Libraries for PHP5
+* 
+* Handles data and output caching. Defaults to /dev/shm
+* (shared memory). All methods are static.
+* 
+* Eg: (output caching)
+* 
+* if (!OutputCache::Start('group', 'unique id', 600)) {
+* 
+*   // ... Output
+* 
+*   OutputCache::End();
+* }
+* 
+* Eg: (data caching)
+* 
+* if (!$data = DataCache::Get('group', 'unique id')) {
+* 
+*   $data = time();
+* 
+*   DataCache::Put('group', 'unique id', 10, $data);
+* }
+* 
+* echo $data;
+*/
+    class Cache
+    {
+        /**
+        * Whether caching is enabled
+        * @var bool
+        */
+        public static $enabled = true;
+
+        /**
+        * Place to store the cache files
+        * @var string
+        */
+        protected static $store = '/dev/shm/';
+        
+        /**
+        * Prefix to use on cache files
+        * @var string
+        */
+        protected static $prefix = 'cache_';
+
+        /**
+        * Stores data
+        * 
+        * @param string $group Group to store data under
+        * @param string $id    Unique ID of this data
+        * @param int    $ttl   How long to cache for (in seconds)
+        */
+        protected static function write($group, $id, $ttl, $data)
+        {
+            $filename = self::getFilename($group, $id);
+            
+            if (self::$enabled && $fp = fopen($filename, 'xb')) {
+            
+                if (flock($fp, LOCK_EX)) {
+                    fwrite($fp, $data);
+                }
+                fclose($fp);
+                
+                // Set filemtime
+                touch($filename, time() + $ttl);
+            }
+        }
+        
+        /**
+        * Reads data
+        * 
+        * @param string $group Group to store data under
+        * @param string $id    Unique ID of this data
+        */
+        protected static function read($group, $id)
+        {
+            $filename = self::getFilename($group, $id);
+            
+            return file_get_contents($filename);
+        }
+        
+        /**
+        * Determines if an entry is cached
+        * 
+        * @param string $group Group to store data under
+        * @param string $id    Unique ID of this data
+        */
+        protected static function isCached($group, $id)
+        {
+            $filename = self::getFilename($group, $id);
+
+            if (self::$enabled && file_exists($filename) && filemtime($filename) > time()) {
+                return true;
+            }
+
+            @unlink($filename);
+
+            return false;
+        }
+        
+        /**
+        * Builds a filename/path from group, id and
+        * store.
+        * 
+        * @param string $group Group to store data under
+        * @param string $id    Unique ID of this data
+        */
+        protected static function getFilename($group, $id)
+        {
+            $id = md5($id);
+
+            return self::$store . self::$prefix . "{$group}_{$id}";
+        }
+        
+        /**
+        * Sets the filename prefix to use
+        * 
+        * @param string $prefix Filename Prefix to use
+        */
+        public static function setPrefix($prefix)
+        {
+            self::$prefix = $prefix;
+        }
+
+        /**
+        * Sets the store for cache files. Defaults to
+        * /dev/shm. Must have trailing slash.
+        * 
+        * @param string $store The dir to store the cache data in
+        */
+        public static function setStore($store)
+        {
+            self::$store = $store;
+        }
+    }
+    
+    /**
+    * Output Cache extension of base caching class
+    */
+    class OutputCache extends Cache
+    {
+        /**
+        * Group of currently being recorded data
+        * @var string
+        */
+        private static $group;
+        
+        /**
+        * ID of currently being recorded data
+        * @var string
+        */
+        private static $id;
+        
+        /**
+        * Ttl of currently being recorded data
+        * @var int
+        */
+        private static $ttl;
+
+        /**
+        * Starts caching off. Returns true if cached, and dumps
+        * the output. False if not cached and start output buffering.
+        * 
+        * @param  string $group Group to store data under
+        * @param  string $id    Unique ID of this data
+        * @param  int    $ttl   How long to cache for (in seconds)
+        * @return bool          True if cached, false if not
+        */
+        public static function Start($group, $id, $ttl)
+        {
+            if (self::isCached($group, $id)) {
+                echo self::read($group, $id);
+                return true;
+            
+            } else {
+                
+                ob_start();
+                
+                self::$group = $group;
+                self::$id    = $id;
+                self::$ttl   = $ttl;
+                
+                return false;
+            }
+        }
+        
+        /**
+        * Ends caching. Writes data to disk.
+        */
+        public static function End()
+        {
+            $data = ob_get_contents();
+            ob_end_flush();
+            
+            self::write(self::$group, self::$id, self::$ttl, $data);
+        }
+    }
+    
+    /**
+    * Data cache extension of base caching class
+    */
+    class DataCache extends Cache
+    {
+    
+        /**
+        * Retrieves data from the cache
+        * 
+        * @param  string $group Group this data belongs to
+        * @param  string $id    Unique ID of the data
+        * @return mixed         Either the resulting data, or null
+        */
+        public static function Get($group, $id)
+        {
+            if (self::isCached($group, $id)) {
+                return unserialize(self::read($group, $id));
+            }
+            
+            return null;
+        }
+        
+        /**
+        * Stores data in the cache
+        * 
+        * @param string $group Group this data belongs to
+        * @param string $id    Unique ID of the data
+        * @param int    $ttl   How long to cache for (in seconds)
+        * @param mixed  $data  The data to store
+        */
+        public static function Put($group, $id, $ttl, $data)
+        {
+            self::write($group, $id, $ttl, serialize($data));
+        }
+    }
+?>
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