Custom Session Class

<?
/*
##############################################
#
#			Filename : session.class
#
#			Created  : 09/01/02 01:47 GMT
#
#	      		Created By  : Syberius
#
#			Version : 1.10
#
##############################################
#
#   The session class below was written to allow session records to
#   be stored in a MySQL database. These custom session functions
#   are used with session_set_save_handler to tell PHP to use the
#   functions in this file and NOT the default functions.
#
#   The ses_start field is use to calculate how long a user has been
#   online. The forumla is time() - ses_start.
#
#   To use simply include/require this file and change the values of the
#   variables defined below!
#
##############################################
#
#   Additions and modifications are allowed as long as this message
#   remains. If you do make changes please contact me at this address.
#
#   [email protected]
#
#   To inform me of any changes to this file.
#S
#
##############################################
#
#   SQL for the basic table structure
#
#   CREATE TABLE d2tp_ses (
#   ses_id varchar(32) NOT NULL default '',
#   ses_time varchar(15) NOT NULL default '',
#   ses_start int(30) NOT NULL default '0',
#   ses_value text NOT NULL,
#   PRIMARY KEY  (ses_id)
#     ) TYPE=MyISAM;
#
##############################################
*/

// Create new object of class
$ses_class = new session($params);

// Change the save_handler to use the class functions
session_set_save_handler(
array(&$ses_class, '_open'),
array(&$ses_class, '_close'),
array(&$ses_class, '_read'),
array(&$ses_class, '_write'),
array(&$ses_class, '_destroy'),
array(&$ses_class, '_gc'));

// Start the session
session_start();

class session
{
	// Define the mysql table you wish to use with this class, this table MUST exist.
	var $ses_table = "ses_table";
	
	// Change to 'Y' if you want to connect to a db in the _open function
	var $db_con = "Y";
	
	// Configure the info to connect to mysql, only required if $db_con is set to 'Y'
	var $db_host = "localhost";
	var $db_user = "user";
	var $db_pass = "pass";
	var $db_dbase = "database";
	
	// Create a connection to a database
	function db_connect() {
		$mysql_connect = @mysql_pconnect($this -> db_host, $this -> db_user, $this -> db_pass);
		$mysql_database = @mysql_select_db($this -> db_dbase);
		
		if (!$mysql_connect || !$mysql_database) {
			return ("false");
		}
		else {
			return ("true");
		}
	}
	
	// Open session, if you have your own db connection code, put it in here!
	function _open($path, $name) {
		if ($this -> db_con == "Y") {
			$this -> db_connect();
		}
		
		return("true");
	}
	
	// Close session
	function _close() {
		$this -> _gc(0); // This is used for a manual call of the session gc function
		return("true");
	}
	
	// Read session data from database
	function _read($ses_id) {
		$session_sql = "SELECT * FROM ".$this -> ses_table."  WHERE ses_id = '$ses_id'";
		$session_res = @mysql_query($session_sql);
		if (!$session_res) {
			return("false");
		}
		
		$session_num = @mysql_num_rows($session_res);
		if ($session_num > 0) {
			$session_row = mysql_fetch_assoc($session_res);
			$ses_data = $session_row["ses_value"];
			return($ses_data);
		}
		else {
			return("");
		}
	}
	
	// Write new data to database
	function _write($ses_id, $data) {
		$session_sql = "UPDATE ".$this -> ses_table."  SET ses_time='".time()."', ses_value='$data' WHERE ses_id='$ses_id'";
		$session_res = @mysql_query($session_sql);
		if (!$session_res) {
			return("false");
		}
		if (mysql_affected_rows()) {
			return("true");
		}
		
		$session_sql = "INSERT INTO ".$this -> ses_table."  (`ses_id`, `ses_time`, `ses_start`, `ses_value`) ";
		$session_sql .= "VALUES ('$ses_id', '".time()."', '". time() ."', '$data')";
		$session_res = @mysql_query($session_sql);
		if (!$session_res) {
			return ("false");
		}
		else {
			return("true");
		}
	}
	
	// Destroy session record in database
	function _destroy($ses_id) {
		$session_sql = "DELETE FROM ".$this -> ses_table."  WHERE ses_id = '$ses_id'";
		$session_res = @mysql_query($session_sql);
		if (!$session_res) {
			return("false");
		}
		else {
			return("true");
		}
	}
	
	// Garbage collection, deletes old sessions
	function _gc($life) {
		$this -> db_connect();
		
		$ses_life = strtotime("-5 minutes");
		
		$session_sql = "DELETE FROM ".$this -> ses_table."  WHERE ses_time < $ses_life";
		$session_res = @mysql_query($session_sql);
		
		if (!$session_res) {
			return("false");
		}
		else {
			return("true");
		}
	}
}
?>