--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/program/lib/Roundcube/rcube_session_memcache.php	Thu Jan 04 15:52:31 2018 -0500
@@ -0,0 +1,179 @@
+<?php
+
+/**
+ +-----------------------------------------------------------------------+
+ | This file is part of the Roundcube Webmail client                     |
+ | Copyright (C) 2005-2014, The Roundcube Dev Team                       |
+ | Copyright (C) 2011, Kolab Systems AG                                  |
+ |                                                                       |
+ | Licensed under the GNU General Public License version 3 or            |
+ | any later version with exceptions for skins & plugins.                |
+ | See the README file for a full license statement.                     |
+ |                                                                       |
+ | PURPOSE:                                                              |
+ |   Provide database supported session management                       |
+ +-----------------------------------------------------------------------+
+ | Author: Thomas Bruederli <roundcube@gmail.com>                        |
+ | Author: Aleksander Machniak <alec@alec.pl>                            |
+ | Author: Cor Bosman <cor@roundcu.bet>                                  |
+ +-----------------------------------------------------------------------+
+*/
+
+/**
+ * Class to provide memcache session storage
+ *
+ * @package    Framework
+ * @subpackage Core
+ * @author     Thomas Bruederli <roundcube@gmail.com>
+ * @author     Aleksander Machniak <alec@alec.pl>
+ * @author     Cor Bosman <cor@roundcu.be>
+ */
+class rcube_session_memcache extends rcube_session
+{
+    private $memcache;
+    private $debug;
+
+    /**
+     * @param Object $config
+     */
+    public function __construct($config)
+    {
+        parent::__construct($config);
+
+        $this->memcache = rcube::get_instance()->get_memcache();
+        $this->debug    = $config->get('memcache_debug');
+
+        if (!$this->memcache) {
+            rcube::raise_error(array(
+                    'code' => 604, 'type' => 'db',
+                    'line' => __LINE__, 'file' => __FILE__,
+                    'message' => "Failed to connect to memcached. Please check configuration"),
+                true, true);
+        }
+
+        // register sessions handler
+        $this->register_session_handler();
+    }
+
+    /**
+     * @param $save_path
+     * @param $session_name
+     * @return bool
+     */
+    public function open($save_path, $session_name)
+    {
+        return true;
+    }
+
+    /**
+     * @return bool
+     */
+    public function close()
+    {
+        return true;
+    }
+
+    /**
+     * Handler for session_destroy() with memcache backend
+     *
+     * @param $key
+     * @return bool
+     */
+    public function destroy($key)
+    {
+        if ($key) {
+            // #1488592: use 2nd argument
+            $result = $this->memcache->delete($key, 0);
+
+            if ($this->debug) {
+                $this->debug('delete', $key, null, $result);
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Read session data from memcache
+     *
+     * @param $key
+     * @return null|string
+     */
+    public function read($key)
+    {
+        if ($value = $this->memcache->get($key)) {
+            $arr = unserialize($value);
+            $this->changed = $arr['changed'];
+            $this->ip      = $arr['ip'];
+            $this->vars    = $arr['vars'];
+            $this->key     = $key;
+        }
+
+        if ($this->debug) {
+            $this->debug('get', $key, $value);
+        }
+
+        return $this->vars ?: '';
+    }
+
+    /**
+     * Write data to memcache storage
+     *
+     * @param $key
+     * @param $vars
+     *
+     * @return bool
+     */
+    public function write($key, $vars)
+    {
+        $data   = serialize(array('changed' => time(), 'ip' => $this->ip, 'vars' => $vars));
+        $result = $this->memcache->set($key, $data, MEMCACHE_COMPRESSED, $this->lifetime + 60);
+
+        if ($this->debug) {
+            $this->debug('set', $key, $data, $result);
+        }
+
+        return $result;
+    }
+
+    /**
+     * Update memcache session data
+     *
+     * @param $key
+     * @param $newvars
+     * @param $oldvars
+     *
+     * @return bool
+     */
+    public function update($key, $newvars, $oldvars)
+    {
+        $ts = microtime(true);
+
+        if ($newvars !== $oldvars || $ts - $this->changed > $this->lifetime / 3) {
+            $data   = serialize(array('changed' => time(), 'ip' => $this->ip, 'vars' => $newvars));
+            $result = $this->memcache->set($key, $data, MEMCACHE_COMPRESSED, $this->lifetime + 60);
+
+            if ($this->debug) {
+                $this->debug('set', $key, $data, $result);
+            }
+
+            return $result;
+        }
+
+        return true;
+    }
+
+    /**
+     * Write memcache debug info to the log
+     */
+    protected function debug($type, $key, $data = null, $result = null)
+    {
+        $line = strtoupper($type) . ' ' . $key;
+
+        if ($data !== null) {
+            $line .= ' ' . $data;
+        }
+
+        rcube::debug('memcache', $line, $result);
+    }
+}