webmaster@1: <?php
webmaster@11: // $Id: session.inc,v 1.44.2.3 2008/09/17 07:53:08 goba Exp $
webmaster@1: 
webmaster@1: /**
webmaster@1:  * @file
webmaster@1:  * User session handling functions.
webmaster@1:  */
webmaster@1: 
webmaster@1: function sess_open($save_path, $session_name) {
webmaster@1:   return TRUE;
webmaster@1: }
webmaster@1: 
webmaster@1: function sess_close() {
webmaster@1:   return TRUE;
webmaster@1: }
webmaster@1: 
webmaster@1: function sess_read($key) {
webmaster@1:   global $user;
webmaster@1: 
webmaster@1:   // Write and Close handlers are called after destructing objects since PHP 5.0.5
webmaster@1:   // Thus destructors can use sessions but session handler can't use objects.
webmaster@1:   // So we are moving session closure before destructing objects.
webmaster@1:   register_shutdown_function('session_write_close');
webmaster@1: 
webmaster@1:   // Handle the case of first time visitors and clients that don't store cookies (eg. web crawlers).
webmaster@1:   if (!isset($_COOKIE[session_name()])) {
webmaster@1:     $user = drupal_anonymous_user();
webmaster@1:     return '';
webmaster@1:   }
webmaster@1: 
webmaster@1:   // Otherwise, if the session is still active, we have a record of the client's session in the database.
webmaster@1:   $user = db_fetch_object(db_query("SELECT u.*, s.* FROM {users} u INNER JOIN {sessions} s ON u.uid = s.uid WHERE s.sid = '%s'", $key));
webmaster@1: 
webmaster@1:   // We found the client's session record and they are an authenticated user
webmaster@1:   if ($user && $user->uid > 0) {
webmaster@1:     // This is done to unserialize the data member of $user
webmaster@1:     $user = drupal_unpack($user);
webmaster@1: 
webmaster@1:     // Add roles element to $user
webmaster@1:     $user->roles = array();
webmaster@1:     $user->roles[DRUPAL_AUTHENTICATED_RID] = 'authenticated user';
webmaster@1:     $result = db_query("SELECT r.rid, r.name FROM {role} r INNER JOIN {users_roles} ur ON ur.rid = r.rid WHERE ur.uid = %d", $user->uid);
webmaster@1:     while ($role = db_fetch_object($result)) {
webmaster@1:       $user->roles[$role->rid] = $role->name;
webmaster@1:     }
webmaster@1:   }
webmaster@1:   // We didn't find the client's record (session has expired), or they are an anonymous user.
webmaster@1:   else {
webmaster@1:     $session = isset($user->session) ? $user->session : '';
webmaster@1:     $user = drupal_anonymous_user($session);
webmaster@1:   }
webmaster@1: 
webmaster@1:   return $user->session;
webmaster@1: }
webmaster@1: 
webmaster@1: function sess_write($key, $value) {
webmaster@1:   global $user;
webmaster@1: 
webmaster@1:   // If saving of session data is disabled or if the client doesn't have a session,
webmaster@11:   // and one isn't being created ($value), do nothing. This keeps crawlers out of
webmaster@11:   // the session table. This reduces memory and server load, and gives more useful
webmaster@11:   // statistics. We can't eliminate anonymous session table rows without breaking
webmaster@11:   // the throttle module and the "Who's Online" block.
webmaster@1:   if (!session_save_session() || (empty($_COOKIE[session_name()]) && empty($value))) {
webmaster@1:     return TRUE;
webmaster@1:   }
webmaster@1: 
webmaster@11:   db_query("UPDATE {sessions} SET uid = %d, cache = %d, hostname = '%s', session = '%s', timestamp = %d WHERE sid = '%s'", $user->uid, isset($user->cache) ? $user->cache : '', ip_address(), $value, time(), $key);
webmaster@11:   if (db_affected_rows()) {
webmaster@1:     // Last access time is updated no more frequently than once every 180 seconds.
webmaster@1:     // This reduces contention in the users table.
webmaster@1:     if ($user->uid && time() - $user->access > variable_get('session_write_interval', 180)) {
webmaster@1:       db_query("UPDATE {users} SET access = %d WHERE uid = %d", time(), $user->uid);
webmaster@1:     }
webmaster@1:   }
webmaster@11:   else {
webmaster@11:     // If this query fails, another parallel request probably got here first.
webmaster@11:     // In that case, any session data generated in this request is discarded.
webmaster@11:     @db_query("INSERT INTO {sessions} (sid, uid, cache, hostname, session, timestamp) VALUES ('%s', %d, %d, '%s', '%s', %d)", $key, $user->uid, isset($user->cache) ? $user->cache : '', ip_address(), $value, time());
webmaster@11:   }
webmaster@1: 
webmaster@1:   return TRUE;
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Called when an anonymous user becomes authenticated or vice-versa.
webmaster@1:  */
webmaster@1: function sess_regenerate() {
webmaster@1:   $old_session_id = session_id();
webmaster@1: 
webmaster@1:   // We code around http://bugs.php.net/bug.php?id=32802 by destroying
webmaster@1:   // the session cookie by setting expiration in the past (a negative
webmaster@1:   // value).  This issue only arises in PHP versions before 4.4.0,
webmaster@1:   // regardless of the Drupal configuration.
webmaster@1:   // TODO: remove this when we require at least PHP 4.4.0
webmaster@1:   if (isset($_COOKIE[session_name()])) {
webmaster@1:     setcookie(session_name(), '', time() - 42000, '/');
webmaster@1:   }
webmaster@1: 
webmaster@1:   session_regenerate_id();
webmaster@1: 
webmaster@1:   db_query("UPDATE {sessions} SET sid = '%s' WHERE sid = '%s'", session_id(), $old_session_id);
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@9:  * Counts how many users have sessions. Can count either anonymous sessions or authenticated sessions.
webmaster@1:  *
webmaster@1:  * @param int $timestamp
webmaster@1:  *   A Unix timestamp representing a point of time in the past.
webmaster@1:  *   The default is 0, which counts all existing sessions.
webmaster@9:  * @param boolean $anonymous
webmaster@1:  *   TRUE counts only anonymous users.
webmaster@1:  *   FALSE counts only authenticated users.
webmaster@1:  * @return  int
webmaster@1:  *   The number of users with sessions.
webmaster@1:  */
webmaster@1: function sess_count($timestamp = 0, $anonymous = true) {
webmaster@1:   $query = $anonymous ? ' AND uid = 0' : ' AND uid > 0';
webmaster@1:   return db_result(db_query('SELECT COUNT(sid) AS count FROM {sessions} WHERE timestamp >= %d'. $query, $timestamp));
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Called by PHP session handling with the PHP session ID to end a user's session.
webmaster@1:  *
webmaster@1:  * @param  string $sid
webmaster@1:  *   the session id
webmaster@1:  */
webmaster@1: function sess_destroy_sid($sid) {
webmaster@1:   db_query("DELETE FROM {sessions} WHERE sid = '%s'", $sid);
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * End a specific user's session
webmaster@1:  *
webmaster@1:  * @param  string $uid
webmaster@1:  *   the user id
webmaster@1:  */
webmaster@1: function sess_destroy_uid($uid) {
webmaster@1:   db_query('DELETE FROM {sessions} WHERE uid = %d', $uid);
webmaster@1: }
webmaster@1: 
webmaster@1: function sess_gc($lifetime) {
webmaster@1:   // Be sure to adjust 'php_value session.gc_maxlifetime' to a large enough
webmaster@1:   // value. For example, if you want user sessions to stay in your database
webmaster@1:   // for three weeks before deleting them, you need to set gc_maxlifetime
webmaster@1:   // to '1814400'. At that value, only after a user doesn't log in after
webmaster@1:   // three weeks (1814400 seconds) will his/her session be removed.
webmaster@1:   db_query("DELETE FROM {sessions} WHERE timestamp < %d", time() - $lifetime);
webmaster@1: 
webmaster@1:   return TRUE;
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Determine whether to save session data of the current request.
webmaster@1:  *
webmaster@1:  * This function allows the caller to temporarily disable writing of session data,
webmaster@1:  * should the request end while performing potentially dangerous operations, such as
webmaster@1:  * manipulating the global $user object.  See http://drupal.org/node/218104 for usage
webmaster@1:  *
webmaster@1:  * @param $status
webmaster@1:  *   Disables writing of session data when FALSE, (re-)enables writing when TRUE.
webmaster@1:  * @return
webmaster@1:  *   FALSE if writing session data has been disabled. Otherwise, TRUE.
webmaster@1:  */
webmaster@1: function session_save_session($status = NULL) {
webmaster@1:   static $save_session = TRUE;
webmaster@1:   if (isset($status)) {
webmaster@1:     $save_session = $status;
webmaster@1:   }
webmaster@1:   return ($save_session);
webmaster@1: }