Шаг второй. Регистрация и авторизация пользователей.

$config[‘sess_use_database’]  = TRUE; // хранить сессии в базе

$autoload['libraries'] = array(‘database’, ‘session’, ‘Userlib’ );

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,
user_data text NOT NULL,
PRIMARY KEY (session_id)
);

CREATE TABLE IF NOT EXISTS `guid` (
  `idguid` smallint(6) NOT NULL AUTO_INCREMENT,
  `useridguid` smallint(6) NOT NULL,
  `textguid` varchar(32) DEFAULT NULL,
  PRIMARY KEY  (`idguid`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;

<?php
 
class Main extends Controller {
 
	function Main()
	{
		parent::Controller();
		$this->load->helper(array('url', 'form'));
		$this->load->library('form_validation');
 
	}
 
	function index()
	{
		$this->load->view('main_view');
	}
 
	function register() {
		$this->form_validation->set_rules('loginuser', 'Username',
		'trim|required|min_length[5]|max_length[32]|xss_clean');
		$this->form_validation->set_rules('passuser', 'Password',
		'required|min_length[5]|max_length[32]|matches[passconf]');
		$this->form_validation->set_rules('passconf', 'Password Confirmation',
		'required');
		$this->form_validation->set_rules('emailuser', 'Email',
		'trim|required|valid_email');
 
		if ($this->form_validation->run() == false) {
			$this->load->view('main_register');
		} else {
			$this->userlib->register($this->input->post('loginuser', true), $this->input->
			post('passuser', true),  $this->input->post('emailuser', true));
			$this->load->view('main_succses.php');
		}
 
	}
 
	function login() {
		$this->userlib->login($this->input->post('idlogin', true), $this->input->
		post('idpassword', true));
		$this->load->view('main_login.php');
	}
 
	function logout() {
		$this->userlib->logout();
		redirect('', 'refresh');
	}
}

CREATE TABLE `ci_sessions` (
  `session_id` varchar(40) NOT NULL DEFAULT '0',
  `ip_address` varchar(16) NOT NULL DEFAULT '0',
  `user_agent` varchar(50) NOT NULL,
  `last_activity` int(10) UNSIGNED NOT NULL DEFAULT '0',
  `user_data` text NOT NULL,
  PRIMARY KEY  (`session_id`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
 
CREATE TABLE `users` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `username` varchar(20) NOT NULL,
  `password` varchar(70) DEFAULT NULL,
  `email` varchar(50) NOT NULL,
  `ip` bigint(10) NOT NULL,
  `groupuser` enum('user','admin','banned','notactive') NOT NULL DEFAULT 'notactive',
  `balance` decimal(10,4) NOT NULL DEFAULT '0.0000',
  PRIMARY KEY  (`id`),
  UNIQUE KEY `email` (`email`),
  UNIQUE KEY `username` (`username`)
) ENGINE=MyISAM AUTO_INCREMENT=4 DEFAULT CHARSET=utf8 AUTO_INCREMENT=4 ;