source: sourcecode/system/database/DB.php @ 1

<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.1.6 or newer
 *
 * @package             CodeIgniter
 * @author              ExpressionEngine Dev Team
 * @copyright   Copyright (c) 2008 - 2011, EllisLab, Inc.
 * @license             http://codeigniter.com/user_guide/license.html
 * @link                http://codeigniter.com
 * @since               Version 1.0
 * @filesource
 */

// ------------------------------------------------------------------------

/**
 * Initialize the database
 *
 * @category    Database
 * @author              ExpressionEngine Dev Team
 * @link                http://codeigniter.com/user_guide/database/
 * @param       string
 * @param       bool    Determines if active record should be used or not
 */
function &DB($params = '', $active_record_override = NULL)
{
        // Load the DB config file if a DSN string wasn't passed
        if (is_string($params) AND strpos($params, '://') === FALSE)
        {
                // Is the config file in the environment folder?
                if ( ! defined('ENVIRONMENT') OR ! file_exists($file_path = APPPATH.'config/'.ENVIRONMENT.'/database.php'))
                {
                        if ( ! file_exists($file_path = APPPATH.'config/database.php'))
                        {
                                show_error('The configuration file database.php does not exist.');
                        }
                }

                include($file_path);

                if ( ! isset($db) OR count($db) == 0)
                {
                        show_error('No database connection settings were found in the database config file.');
                }

                if ($params != '')
                {
                        $active_group = $params;
                }

                if ( ! isset($active_group) OR ! isset($db[$active_group]))
                {
                        show_error('You have specified an invalid database connection group.');
                }

                $params = $db[$active_group];
        }
        elseif (is_string($params))
        {

                /* parse the URL from the DSN string
                 *  Database settings can be passed as discreet
                 *  parameters or as a data source name in the first
                 *  parameter. DSNs must have this prototype:
                 *  $dsn = 'driver://username:password@hostname/database';
                 */

                if (($dns = @parse_url($params)) === FALSE)
                {
                        show_error('Invalid DB Connection String');
                }

                $params = array(
                                                        'dbdriver'      => $dns['scheme'],
                                                        'hostname'      => (isset($dns['host'])) ? rawurldecode($dns['host']) : '',
                                                        'username'      => (isset($dns['user'])) ? rawurldecode($dns['user']) : '',
                                                        'password'      => (isset($dns['pass'])) ? rawurldecode($dns['pass']) : '',
                                                        'database'      => (isset($dns['path'])) ? rawurldecode(substr($dns['path'], 1)) : ''
                                                );

                // were additional config items set?
                if (isset($dns['query']))
                {
                        parse_str($dns['query'], $extra);

                        foreach ($extra as $key => $val)
                        {
                                // booleans please
                                if (strtoupper($val) == "TRUE")
                                {
                                        $val = TRUE;
                                }
                                elseif (strtoupper($val) == "FALSE")
                                {
                                        $val = FALSE;
                                }

                                $params[$key] = $val;
                        }
                }
        }

        // No DB specified yet?  Beat them senseless...
        if ( ! isset($params['dbdriver']) OR $params['dbdriver'] == '')
        {
                show_error('You have not selected a database type to connect to.');
        }

        // Load the DB classes.  Note: Since the active record class is optional
        // we need to dynamically create a class that extends proper parent class
        // based on whether we're using the active record class or not.
        // Kudos to Paul for discovering this clever use of eval()

        if ($active_record_override !== NULL)
        {
                $active_record = $active_record_override;
        }

        require_once(BASEPATH.'database/DB_driver.php');

        if ( ! isset($active_record) OR $active_record == TRUE)
        {
                require_once(BASEPATH.'database/DB_active_rec.php');

                if ( ! class_exists('CI_DB'))
                {
                        eval('class CI_DB extends CI_DB_active_record { }');
                }
        }
        else
        {
                if ( ! class_exists('CI_DB'))
                {
                        eval('class CI_DB extends CI_DB_driver { }');
                }
        }

        require_once(BASEPATH.'database/drivers/'.$params['dbdriver'].'/'.$params['dbdriver'].'_driver.php');

        // Instantiate the DB adapter
        $driver = 'CI_DB_'.$params['dbdriver'].'_driver';
        $DB = new $driver($params);

        if ($DB->autoinit == TRUE)
        {
                $DB->initialize();
        }

        if (isset($params['stricton']) && $params['stricton'] == TRUE)
        {
                $DB->query('SET SESSION sql_mode="STRICT_ALL_TABLES"');
        }

        return $DB;
}



/* End of file DB.php */
/* Location: ./system/database/DB.php */