<?php if (!defined('BASEPATH')) exit('No direct script access allowed');
// ------------------------------------------------------------------------
/**
* Session Class
*
* @package CodeIgniter
* @subpackage Libraries
* @category Sessions
* @author Dready
* @inpiredFrom Session class by Rick Ellis
* @inspireFrom Native_Session by Dariusz Debowczyk
* @link http://dready.jexiste.fr/dotclear/index.php?2006/09/13/19-reworked-session-handler-for-code-igniter
*/
class Session {
var $now;
var $encryption = TRUE;
var $use_database = FALSE;
var $session_table = FALSE;
var $sess_length = 7200;
var $sess_cookie = 'ci_session';
var $userdata = array();
var $gc_probability = 5;
var $cookie_sent = FALSE;
var $object;
var $flash_key = 'flash'; // prefix for "flash" variables (eg. flash:new:message)
/**
* Session Constructor
*
* The constructor runs the session routines automatically
* whenever the class is instantiated.
*/
function Session()
{
$this->object =& get_instance();
log_message('debug', "Session Class Initialized (db)");
$this->sess_run();
}
// --------------------------------------------------------------------
/**
* Run the session routines
*
* @access public
* @return void
*/
function sess_run()
{
// We MUST use a database !
if ($this->object->config->item('sess_use_database') === TRUE AND $this->object->config->item('sess_table_name') != '')
{
$this->use_database = TRUE;
$this->session_table = $this->object->config->item('sess_table_name');
$this->object->load->database();
} else {
log_message('error',__CLASS__.': sessions requires a database');
return FALSE;
}
/*
* Set the "now" time
*
// * It can either set to GMT or time(). The pref
* is set in the config file. If the developer
* is doing any sort of time localization they
* might want to set the session time to GMT so
* they can offset the "last_activity" and
* "last_visit" times based on each user's locale.
*
*/
if (strtolower($this->object->config->item('time_reference')) == 'gmt')
{
$now = time();
$this->now = mktime(gmdate("H", $now), gmdate("i", $now), gmdate("s", $now), gmdate("m", $now), gmdate("d", $now), gmdate("Y", $now));
if (strlen($this->now) < 10)
{
$this->now = time();
log_message('error', 'The session class could not set a proper GMT timestamp so the local time() value was used.');
}
}
else
{
$this->now = time();
}
/*
* Set the session length
*
* If the session expiration is set to zero in
* the config file we'll set the expiration
* two years from now.
*
*/
$expiration = $this->object->config->item('sess_expiration');
if (is_numeric($expiration))
{
if ($expiration > 0)
{
$this->sess_length = $this->object->config->item('sess_expiration');
}
else
{
$this->sess_length = (60*60*24*365*2);
}
}
// Set the cookie name
if ($this->object->config->item('sess_cookie_name') != FALSE)
{
$this->sess_cookie = $this->object->config->item('cookie_prefix').$this->object->config->item('sess_cookie_name');
}
/*
* Fetch the current session
*
* If a session doesn't exist we'll create
* a new one. If it does, we'll update it.
*
*/
if ( ! $this->sess_read())
{
$this->sess_create();
}
else
{
// We only update the session every five minutes
if (($this->userdata['last_activity'] + 300) < $this->now)
{
$this->sess_update();
}
}
// Delete expired sessions if necessary
$this->sess_gc();
// delete old flashdata (from last request)
$this->_flashdata_sweep();
// mark all new flashdata as old (data will be deleted before next request)
$this->_flashdata_mark();
}
// END sess_run()
// --------------------------------------------------------------------
/**
* Fetch the current session data if it exists
*
* @access public
* @return void
*/
function sess_read()
{
// Fetch the cookie
$session_id = $this->object->input->cookie($this->sess_cookie);
if ($session_id === FALSE)
{
log_message('debug', 'A session cookie was not found.');
return FALSE;
}
// Is there a corresponding session in the DB?
$this->object->db->where('session_id', $session_id);
// session should not have expired
$this->object->db->where('last_activity >', ($this->now - $this->sess_length) );
// matching IP ?
if ($this->object->config->item('sess_match_ip') == TRUE)
{
$this->object->db->where('ip_address', $this->object->input->ip_address());
}
// matching user agent ?
if ($this->object->config->item('sess_match_useragent') == TRUE)
{
$this->object->db->where('user_agent', substr($this->object->input->user_agent(), 0, 50));
}
$query = $this->object->db->get($this->session_table);
if ($query->num_rows() == 0)
{
$this->sess_destroy();
return FALSE;
}
else
{
$row = $query->row();
if (($row->last_activity + $this->sess_length) < $this->now)
{
$this->object->db->where('session_id', $session_id);
$this->object->db->delete($this->session_table);
$this->sess_destroy();
return FALSE;
} else {
$session = @unserialize($row->session_data);
if ( ! is_array($session) ) {
$session = array();
}
$session['session_id'] = $session_id;
$session['ip_address'] = $row->ip_address;
$session['user_agent'] = $row->user_agent;
$session['last_activity'] = $row->last_activity;
}
}
// Session is valid!
$this->userdata = $session;
unset($session);
return TRUE;
}
// END sess_read()
// --------------------------------------------------------------------
/**
* Write the session cookie
*
* @access public
* @param boolean true if we want to send cookie even if a cookie has already been sent
* @return void
*/
function sess_send_cookie($force = FALSE)
{
if ( !$force && $this->cookie_sent ) return;
log_message('debug','sending session cookie');
setcookie(
$this->sess_cookie,
$this->userdata['session_id'],
$this->sess_length + $this->now,
$this->object->config->item('cookie_path'),
$this->object->config->item('cookie_domain'),
0
);
$this->cookie_sent = TRUE;
}
// END sess_send_cookie()
// --------------------------------------------------------------------
/**
* Create a new session
*
* @access public
* @return void
*/
function sess_create()
{
$sessid = '';
while (strlen($sessid) < 32)
{
$sessid .= mt_rand(0, mt_getrandmax());
}
$this->userdata = array(
'session_id' => md5(uniqid($sessid, TRUE)),
'ip_address' => $this->object->input->ip_address(),
'user_agent' => substr($this->object->input->user_agent(), 0, 50),
'last_activity' => $this->now
);
$this->object->db->query($this->object->db->insert_string($this->session_table, $this->userdata));
// Write the cookie
$this->sess_send_cookie();
}
// END sess_create()
// --------------------------------------------------------------------
/**
* Update an existing session
*
* @access public
* @return void
*/
function sess_update()
{
$this->userdata['last_activity'] = $this->now;
// format query array to update database
$ud = $this->userdata;
$query_array = array( 'last_activity' => $ud['last_activity'],
'user_agent' => $ud['user_agent'],
'ip_address' => $ud['ip_address'] );
unset($ud['session_id']);
unset($ud['last_activity']);
unset($ud['user_agent']);
unset($ud['ip_address']);
$query_array['session_data'] = serialize($ud);
$this->object->db->query($this->object->db->update_string($this->session_table, $query_array, array('session_id' => $this->userdata['session_id'])));
// Write the cookie
$this->sess_send_cookie();
}
// END sess_update()
// --------------------------------------------------------------------
/**
* Destroy the current session
*
* @access public
* @return void
*/
function sess_destroy()
{
setcookie(
$this->sess_cookie,
'',
($this->now - 31500000),
$this->object->config->item('cookie_path'),
$this->object->config->item('cookie_domain'),
0
);
}
// END sess_destroy()
// --------------------------------------------------------------------
/**
* Garbage collection
*
* This deletes expired session rows from database
* if the probability percentage is met
*
* @access public
* @return void
*/
function sess_gc()
{
srand(time());
if ((rand() % 100) < $this->gc_probability)
{
$expire = $this->now - $this->sess_length;
$this->object->db->where("last_activity < {$expire}");
$this->object->db->delete($this->session_table);
log_message('debug', 'Session garbage collection performed.');
}
}
// END sess_gc()
// --------------------------------------------------------------------
/**
* Fetch a specific item form the session array
*
* @access public
* @param string
* @return string
*/
function userdata($item = '')
{
if ( ! strlen($item) ) return $this->userdata;
return ( ! isset($this->userdata[$item])) ? FALSE : $this->userdata[$item];
}
// END userdata()
// --------------------------------------------------------------------
/**
* Add or change data in the "userdata" array
*
* @access public
* @param mixed
* @param string
* @return void
*/
function set_userdata($newdata = array(), $newval = '')
{
if (is_string($newdata))
{
$newdata = array($newdata => $newval);
}
if (count($newdata) > 0)
{
foreach ($newdata as $key => $val)
{
$this->userdata[$key] = $val;
}
}
$this->sess_update();
}
// END set_userdata()
// --------------------------------------------------------------------
/**
* Delete a session variable from the "userdata" array
*
* @access array
* @return void
*/
function unset_userdata($newdata = array())
{
if (is_string($newdata))
{
$newdata = array($newdata => '');
}
if (count($newdata) > 0)
{
foreach ($newdata as $key => $val)
{
unset($this->userdata[$key]);
}
}
$this->sess_update();
}
// END unset_userdata()
/**
* Sets "flash" data which will be available only in next request (then it will
* be deleted from session). You can use it to implement "Save succeeded" messages
* after redirect.
*/
function set_flashdata($key, $value)
{
$flash_key = $this->flash_key.':new:'.$key;
$this->set_userdata($flash_key, $value);
}
/**
* Keeps existing "flash" data available to next request.
*/
function keep_flashdata($key)
{
$old_flash_key = $this->flash_key.':old:'.$key;
$value = $this->userdata($old_flash_key);
$new_flash_key = $this->flash_key.':new:'.$key;
$this->set_userdata($new_flash_key, $value);
}
/**
* Returns "flash" data for the given key.
*/
function flashdata($key)
{
$flash_key = $this->flash_key.':old:'.$key;
return $this->userdata($flash_key);
}
/**
* PRIVATE: Internal method - marks "flash" session attributes as 'old'
*/
function _flashdata_mark()
{
$userdata = $this->userdata();
foreach ($userdata as $name => $value)
{
$parts = explode(':new:', $name);
if (is_array($parts) && count($parts) == 2)
{
$new_name = $this->flash_key.':old:'.$parts[1];
$this->set_userdata($new_name, $value);
$this->unset_userdata($name);
}
}
}
/**
* PRIVATE: Internal method - removes "flash" session marked as 'old'
*/
function _flashdata_sweep()
{
$userdata = $this->userdata();
foreach ($userdata as $name => $value)
{
$parts = explode(':old:', $name);
if (is_array($parts) && count($parts) == 2 && $parts[0] == $this->flash_key)
{
$this->unset_userdata($name);
}
}
}
// --------------------------------------------------------------------
}
// END Session Class
/*
CREATE TABLE IF NOT EXISTS `ci_sessions` (
session_id varchar(40) DEFAULT '0' NOT NULL,
ip_address varchar(16) DEFAULT '0' NOT NULL,
user_agent varchar(50) NOT NULL,
last_activity int(10) unsigned DEFAULT 0 NOT NULL,
session_data text default '' not null,
PRIMARY KEY (session_id)
);
*/
?>
Pastie << self Blog
