Initial version of new Session library

1 files changed, 317 insertions, 0 deletions

diff --git a/system/libraries/Session/drivers/Session_database_driver.php b/system/libraries/Session/drivers/Session_database_driver.php
new file mode 100644
index 000000000..24847456c
--- /dev/null
+++ b/system/libraries/Session/drivers/Session_database_driver.php
@@ -0,0 +1,317 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP 5.2.4 or newer
+ *
+ * NOTICE OF LICENSE
+ *
+ * Licensed under the Open Software License version 3.0
+ *
+ * This source file is subject to the Open Software License (OSL 3.0) that is
+ * bundled with this package in the files license.txt / license.rst.  It is
+ * also available through the world wide web at this URL:
+ * http://opensource.org/licenses/OSL-3.0
+ * If you did not receive a copy of the license and are unable to obtain it
+ * through the world wide web, please send an email to
+ * licensing@ellislab.com so we can send you a copy immediately.
+ *
+ * @package		CodeIgniter
+ * @author		Andrey Andreev
+ * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
+ * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
+ * @link		http://codeigniter.com
+ * @since		Version 3.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * CodeIgniter Session Database Driver
+ *
+ * @package		CodeIgniter
+ * @subpackage	Libraries
+ * @category	Sessions
+ * @author		Andrey Andreev
+ * @link		http://codeigniter.com/user_guide/libraries/sessions.html
+ */
+class CI_Session_database_driver extends CI_Session_driver implements SessionHandlerInterface {
+
+	/**
+	 * DB object
+	 *
+	 * @var	object
+	 */
+	protected $_db;
+
+	/**
+	 * DB table
+	 *
+	 * @var	string
+	 */
+	protected $_table;
+
+	/**
+	 * Session ID
+	 *
+	 * @var	string
+	 */
+	protected $_session_id;
+
+	/**
+	 * Row exists flag
+	 *
+	 * @var	bool
+	 */
+	protected $_row_exists = FALSE;
+
+	/**
+	 * Lock "driver" flag
+	 *
+	 * @var	string
+	 */
+	protected $_lock_driver;
+
+	/**
+	 * Lock status flag
+	 *
+	 * @var	bool
+	 */
+	protected $_lock = FALSE;
+
+	/**
+	 * Semaphore ID
+	 *
+	 * Used for locking if the database doesn't support advisory locks
+	 *
+	 * @var	resource
+	 */
+	protected $_sem;
+
+	// ------------------------------------------------------------------------
+
+	/**
+	 * Class constructor
+	 *
+	 * @param	array	$params	Configuration parameters
+	 * @return	void
+	 */
+	public function __construct(&$params)
+	{
+		parent::__construct($params);
+
+		$CI =& get_instance();
+		isset($CI->db) OR $CI->load->database();
+		$this->_db =& $CI->db;
+
+		if ( ! $this->_db instanceof CI_DB_query_builder)
+		{
+			throw new Exception('Query Builder not enabled for the configured database. Aborting.');
+		}
+		elseif ($this->_db->pconnect)
+		{
+			throw new Exception('Configured database connection is persistent. Aborting.');
+		}
+
+		$db_driver = $this->_db->dbdriver.(empty($this->_db->subdriver) ? '' : '_'.$this->_db->subdriver);
+		if (strpos($db_driver, 'mysql') !== FALSE)
+		{
+			$this->_lock_type = 'mysql';
+		}
+		elseif (in_array($db_driver, array('postgre', 'pdo_pgsql'), TRUE))
+		{
+			$this->_lock_type = 'postgre';
+		}
+		elseif (extension_loaded('sysvsem'))
+		{
+			$this->_lock_type = 'semaphore';
+		}
+
+		isset($this->_table) OR $this->_table = config_item('sess_table_name');
+	}
+
+	// ------------------------------------------------------------------------
+
+	public function open($save_path, $name)
+	{
+		return empty($this->_db->conn_id)
+			? ( ! $this->_db->autoinit && $this->_db->db_connect())
+			: TRUE;
+	}
+
+	// ------------------------------------------------------------------------
+
+	public function read($session_id)
+	{
+		$this->_session_id = $session_id;
+		if (($this->_lock = $this->_get_lock()) !== FALSE)
+		{
+			$this->_db
+				->select('data')
+				->from($this->_table)
+				->where('id', $session_id);
+
+			if ($this->_match_ip)
+			{
+				$this->_db->where('ip_address', $_SERVER['REMOTE_ADDR']);
+			}
+
+			if (($result = $this->_db->get()->row()) === NULL)
+			{
+				$this->_fingerprint = md5('');
+				return '';
+			}
+
+			$this->_fingerprint = md5(rtrim($result->data));
+			$this->_row_exists = TRUE;
+			return $result->data;
+		}
+
+		$this->_fingerprint = md5('');
+		return '';
+	}
+
+	public function write($session_id, $session_data)
+	{
+		if ($this->_lock === FALSE)
+		{
+			return FALSE;
+		}
+
+		if ($this->_row_exists === FALSE)
+		{
+			if ($this->_db->insert($this->_table, array('id' => $session_id, 'ip_address' => $_SERVER['REMOTE_ADDR'], 'timestamp' => time(), 'data' => $session_data)))
+			{
+				$this->_fingerprint = md5($session_data);
+				return $this->_row_exists = TRUE;
+			}
+
+			return FALSE;
+		}
+
+		$this->_db->where('id', $session_id);
+		if ($this->_match_ip)
+		{
+			$this->_db->where('ip_address', $_SERVER['REMOTE_ADDR']);
+		}
+
+		$update_data = ($this->_fingerprint === md5($session_data))
+			? array('timestamp' => time())
+			: array('timestamp' => time(), 'data' => $session_data);
+
+		if ($this->_db->update($this->_table, $update_data))
+		{
+			$this->_fingerprint = md5($session_data);
+			return TRUE;
+		}
+
+		return FALSE;
+	}
+
+	// ------------------------------------------------------------------------
+
+	public function close()
+	{
+		return ($this->_lock)
+			? $this->_release_lock()
+			: TRUE;
+	}
+
+	// ------------------------------------------------------------------------
+
+	public function destroy($session_id)
+	{
+		if ($this->_lock)
+		{
+			$this->_db->where('id', $session_id);
+			if ($this->_match_ip)
+			{
+				$this->_db->where('ip_address', $_SERVER['REMOTE_ADDR']);
+			}
+
+			return $this->_db->delete($this->_table)
+				? ($this->close() && $this->_cookie_destroy())
+				: FALSE;
+		}
+
+		return ($this->close() && $this->_cookie_destroy());
+	}
+
+	// ------------------------------------------------------------------------
+
+	public function gc($maxlifetime)
+	{
+		return $this->_db->delete($this->_table, 'timestamp < '.(time() - $maxlifetime));
+	}
+
+	// ------------------------------------------------------------------------
+
+	protected function _get_lock()
+	{
+		$arg = $this->_session_id
+			.($this->_match_ip ? '_'.$_SERVER['REMOTE_ADDR'] : '');
+
+		if ($this->_lock_driver === 'mysql')
+		{
+			return (bool) $this->_db
+				->query("SELECT GET_LOCK('".$session_id."', 10) AS ci_session_lock")
+				->row()
+				->ci_session_lock;
+		}
+		elseif ($this->_lock_driver === 'postgre')
+		{
+			return (bool) $this->_db->simple_query('SELECT pg_advisory_lock('.$arg.')');
+		}
+		elseif ($this->_lock_driver === 'semaphore')
+		{
+			if (($this->_sem = sem_get($arg, 1, 0644)) === FALSE)
+			{
+				return FALSE;
+			}
+
+			if ( ! sem_acquire($this->_sem))
+			{
+				sem_remove($this->_sem);
+				return FALSE;
+			}
+
+			return TRUE;
+		}
+
+		return TRUE;
+	}
+
+	// ------------------------------------------------------------------------
+
+	protected function _release_lock()
+	{
+		if ($this->_lock_driver === 'mysql')
+		{
+			$arg = $this->_session_id
+				.($this->_match_ip ? '_'.$_SERVER['REMOTE_ADDR'] : '');
+
+			return (bool) $this->_db
+				->query("SELECT RELEASE_LOCK('".$arg."') AS ci_session_lock")
+				->row()
+				->ci_session_lock;
+		}
+		elseif ($this->_lock_driver === 'postgre')
+		{
+			$arg = "hashtext('".$this->_session_id."')"
+				.($this->_match_ip ? ", hashtext('".$_SERVER['REMOTE_ADDR']."')" : '');
+
+			return (bool) $this->_db->simple_query('SELECT pg_advisory_unlock('.$arg.')');
+		}
+		elseif ($this->_lock_driver === 'semaphore')
+		{
+			sem_release($this->_sem);
+			sem_remove($this->_sem);
+		}
+
+		return TRUE;
+	}
+
+}
+
+/* End of file Session_database_driver.php */
+/* Location: ./system/libraries/Session/drivers/Session_database_driver.php */
\ No newline at end of file