--- /dev/null
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\HttpFoundation\Session\Storage;
+
+use Symfony\Component\HttpFoundation\Session\SessionBagInterface;
+
+/**
+ * Metadata container.
+ *
+ * Adds metadata to the session.
+ *
+ * @author Drak <drak@zikula.org>
+ */
+class MetadataBag implements SessionBagInterface
+{
+ const CREATED = 'c';
+ const UPDATED = 'u';
+ const LIFETIME = 'l';
+
+ /**
+ * @var string
+ */
+ private $name = '__metadata';
+
+ /**
+ * @var string
+ */
+ private $storageKey;
+
+ /**
+ * @var array
+ */
+ protected $meta = array(self::CREATED => 0, self::UPDATED => 0, self::LIFETIME => 0);
+
+ /**
+ * Unix timestamp.
+ *
+ * @var int
+ */
+ private $lastUsed;
+
+ /**
+ * @var int
+ */
+ private $updateThreshold;
+
+ /**
+ * Constructor.
+ *
+ * @param string $storageKey The key used to store bag in the session
+ * @param int $updateThreshold The time to wait between two UPDATED updates
+ */
+ public function __construct($storageKey = '_sf2_meta', $updateThreshold = 0)
+ {
+ $this->storageKey = $storageKey;
+ $this->updateThreshold = $updateThreshold;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function initialize(array &$array)
+ {
+ $this->meta = &$array;
+
+ if (isset($array[self::CREATED])) {
+ $this->lastUsed = $this->meta[self::UPDATED];
+
+ $timeStamp = time();
+ if ($timeStamp - $array[self::UPDATED] >= $this->updateThreshold) {
+ $this->meta[self::UPDATED] = $timeStamp;
+ }
+ } else {
+ $this->stampCreated();
+ }
+ }
+
+ /**
+ * Gets the lifetime that the session cookie was set with.
+ *
+ * @return int
+ */
+ public function getLifetime()
+ {
+ return $this->meta[self::LIFETIME];
+ }
+
+ /**
+ * Stamps a new session's metadata.
+ *
+ * @param int $lifetime Sets the cookie lifetime for the session cookie. A null value
+ * will leave the system settings unchanged, 0 sets the cookie
+ * to expire with browser session. Time is in seconds, and is
+ * not a Unix timestamp.
+ */
+ public function stampNew($lifetime = null)
+ {
+ $this->stampCreated($lifetime);
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function getStorageKey()
+ {
+ return $this->storageKey;
+ }
+
+ /**
+ * Gets the created timestamp metadata.
+ *
+ * @return int Unix timestamp
+ */
+ public function getCreated()
+ {
+ return $this->meta[self::CREATED];
+ }
+
+ /**
+ * Gets the last used metadata.
+ *
+ * @return int Unix timestamp
+ */
+ public function getLastUsed()
+ {
+ return $this->lastUsed;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function clear()
+ {
+ // nothing to do
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function getName()
+ {
+ return $this->name;
+ }
+
+ /**
+ * Sets name.
+ *
+ * @param string $name
+ */
+ public function setName($name)
+ {
+ $this->name = $name;
+ }
+
+ private function stampCreated($lifetime = null)
+ {
+ $timeStamp = time();
+ $this->meta[self::CREATED] = $this->meta[self::UPDATED] = $this->lastUsed = $timeStamp;
+ $this->meta[self::LIFETIME] = (null === $lifetime) ? ini_get('session.cookie_lifetime') : $lifetime;
+ }
+}