moodle/lib/setup.php

<?php
/**
 * setup.php - Sets up sessions, connects to databases and so on
 *
 * Normally this is only called by the main config.php file 
 * Normally this file does not need to be edited. 
 * @author Martin Dougiamas
 * @version $Id$
 * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
 * @package moodlecore
 */

////// DOCUMENTATION IN PHPDOC FORMAT FOR MOODLE GLOBALS AND COMMON OBJECT TYPES /////////////
/**
 * This global variable is read in from the 'config' table.
 *
 * Some typical settings in the $CFG global:
 *  - $USER->emailstop - Does the user want email sent to them?
 *  - $USER->email - The user's email address.
 *  - $USER->id - The unique integer identified of this user in the 'user' table.
 *  - $USER->email - The user's email address.
 *  - $USER->firstname - The user's first name.
 *  - $USER->lastname - The user's last name.
 *  - $USER->username - The user's login username.
 *  - $USER->secret - The user's ?.
 *  - $USER->lang - The user's language choice.
 *
 * @global object(user) $USER 
 */
global $USER;
/**
 * $USER is a global instance of a typical $user record. 
 *
 * Items found in the user record:
 *  - $CFG->wwwroot - Path to moodle index directory in url format.
 *  - $CFG->dataroot - Path to moodle index directory on server's filesystem.
 *  - $CFG->libroot  - Path to moodle's library folder on server's filesystem.
 *
 * @global object(cfg) $CFG
 */
global $CFG;
/**
 * Definition of session type
 * @global object(session) $SESSION 
 */
global $SESSION;
/**
 * Definition of course type
 * @global object(course) $COURSE 
 */
global $COURSE;
/**
 * Definition of db type
 * @global object(db) $db 
 */
global $db;
/**
 * $THEME is a global that defines the site theme.
 *
 * Items found in the theme record:
 *  - $THEME->cellheading - Cell colors.
 *  - $THEME->cellheading2 - Alternate cell colors.
 *
 * @global object(theme) $THEME 
 */
global $THEME;

    if (!isset($CFG->wwwroot)) {
        die;
    }
    
/// If there are any errors in the standard libraries we want to know!
    error_reporting(E_ALL);

/// Connect to the database using adodb

    $CFG->libdir   = $CFG->dirroot .'/lib';

    require_once($CFG->libdir .'/adodb/adodb.inc.php'); // Database access functions

    $db = &ADONewConnection($CFG->dbtype);         

    error_reporting(0);  // Hide errors 

    if (!isset($CFG->dbpersist) or !empty($CFG->dbpersist)) {    // Use persistent connection (default)
        $dbconnected = $db->PConnect($CFG->dbhost,$CFG->dbuser,$CFG->dbpass,$CFG->dbname);
    } else {                                                     // Use single connection
        $dbconnected = $db->Connect($CFG->dbhost,$CFG->dbuser,$CFG->dbpass,$CFG->dbname);
    }
    if (! $dbconnected) {
        echo '<table align="center"><tr>';
        echo '<td style="color:#990000; text-align:center; font-size:large; border-width:1px; '.
             '    border-color:#000000; border-style:solid; border-radius: 20px; border-collapse: collapse; '.
             '    -moz-border-radius: 20px; padding: 15px">';
        echo '<p>Error: Database connection failed.</p>';
        echo '<p>It is possible that the database is overloaded or otherwise not running properly.</p>';
        echo '<p>The site administrator should also check that the database details have been correctly specified in config.php</p>';
        echo '</td></tr></table>';
        die;
    }

    error_reporting(E_ALL);       // Show errors from now on.

    if (!isset($CFG->prefix)) {   // Just in case it isn't defined in config.php
        $CFG->prefix = '';
    }


/// Define admin directory

    if (!isset($CFG->admin)) {   // Just in case it isn't defined in config.php
        $CFG->admin = 'admin';   // This is relative to the wwwroot and dirroot
    }


/// Load up standard libraries 

    require_once($CFG->libdir .'/weblib.php');          // Functions for producing HTML
    require_once($CFG->libdir .'/datalib.php');         // Functions for accessing databases
    require_once($CFG->libdir .'/moodlelib.php');       // Other general-purpose functions


/// Increase memory limits if possible

    raise_memory_limit('64M');    // We should never NEED this much but just in case...        


/// Load up any configuration from the config table
    
    if ($configs = get_records('config')) {
        $CFG = (array)$CFG;
        foreach ($configs as $config) {
            if (!isset($CFG[$config->name])) {
                $CFG[$config->name] = $config->value;
            } else {
                error_log("\$CFG->$config->name in config.php overrides database setting");
            }
        }

        $CFG = (object)$CFG;
        unset($configs);
        unset($config);
    }



/// Set error reporting back to normal
    if (empty($CFG->debug)) {
        $CFG->debug = 7;
    }
    error_reporting($CFG->debug);


/// Set a default enrolment configuration (see bug 1598)
    if (!isset($CFG->enrol)) {
        $CFG->enrol = 'internal';
    }

/// File permissions on created directories in the $CFG->dataroot

    if (empty($CFG->directorypermissions)) {
        $CFG->directorypermissions = 0777;      // Must be octal (that's why it's here)
    }

/// Set up smarty template system
    //require_once($CFG->libdir .'/smarty/Smarty.class.php');  
    //$smarty = new Smarty;
    //$smarty->template_dir = $CFG->dirroot .'/templates/'. $CFG->template;
    //if (!file_exists($CFG->dataroot .'/cache')) {
    //    make_upload_directory('cache');
    //}
    //$smarty->compile_dir = $CFG->dataroot .'/cache';

/// Set up session handling 
    if (empty($CFG->dbsessions)) {   /// File-based sessions
        if (!empty($CFG->sessiontimeout)) {
            ini_set('session.gc_maxlifetime', $CFG->sessiontimeout);
        }
    
        if (!file_exists($CFG->dataroot .'/sessions')) {
            make_upload_directory('sessions');
        }
        ini_set('session.save_path', $CFG->dataroot .'/sessions');

    } else {                         /// Database sessions
	    ini_set('session.save_handler', 'user');

	    $ADODB_SESSION_DRIVER  = $CFG->dbtype;
	    $ADODB_SESSION_CONNECT = $CFG->dbhost;
	    $ADODB_SESSION_USER    = $CFG->dbuser;
	    $ADODB_SESSION_PWD     = $CFG->dbpass;
	    $ADODB_SESSION_DB      = $CFG->dbname;
	    $ADODB_SESSION_TBL     = $CFG->prefix.'sessions';
        
	    require_once($CFG->libdir. '/adodb/session/adodb-session.php');
    }

/// Set sessioncookie variable if it isn't already
    if (!isset($CFG->sessioncookie)) {
        $CFG->sessioncookie = '';
    }

/// Configure ampersands in URLs

    @ini_set('arg_separator.output', '&amp;');

/// Location of standard files

    $CFG->wordlist    = $CFG->libdir .'/wordlist.txt';
    $CFG->javascript  = $CFG->libdir .'/javascript.php';
    $CFG->moddata     = 'moddata';


/// A hack to get around magic_quotes_gpc being turned off

    if (!ini_get_bool('magic_quotes_gpc') ) {
        foreach ($_GET as $key => $var) {
            if (!is_array($var)) {
                $_GET[$key] = addslashes($var);
            } else {
                foreach ($var as $arrkey => $arrvar) {
                    $var[$arrkey] = addslashes($arrvar);
                }
                $_GET[$key] = $var;
            }
        }
        foreach ($_POST as $key => $var) {
            if (!is_array($var)) {
                $_POST[$key] = addslashes($var);
            } else {
                foreach ($var as $arrkey => $arrvar) {
                    $var[$arrkey] = addslashes($arrvar);
                }
                $_POST[$key] = $var;
            }
        }
        foreach ($_COOKIE as $key => $var) {
            if (!is_array($var)) {
                $_COOKIE[$key] = addslashes($var);
            } else {
                foreach ($var as $arrkey => $arrvar) {
                    $var[$arrkey] = addslashes($arrvar);
                }
                $_COOKIE[$key] = $var;
            }
        }
    }


/// The following is a hack to get around the problem of PHP installations
/// that have "register_globals" turned off (default since PHP 4.1.0).
/// Eventually I'll go through and upgrade all the code to make this unnecessary

    if (isset($_GET)) {
        extract($_GET, EXTR_SKIP);    // Skip existing variables, ie CFG
    }
    if (isset($_POST)) {
        extract($_POST, EXTR_SKIP);   // Skip existing variables, ie CFG
    }
    if (isset($_SERVER)) { 
        extract($_SERVER);
    }

    
/// Load up global environment variables

    class object {};

    unset(${'MoodleSession'.$CFG->sessioncookie});
    unset($_GET['MoodleSession'.$CFG->sessioncookie]);
    unset($_POST['MoodleSession'.$CFG->sessioncookie]);

    if (!isset($nomoodlecookie)) {
        session_name('MoodleSession'.$CFG->sessioncookie);
        @session_start();
        if (! isset($_SESSION['SESSION'])) { 
            $_SESSION['SESSION'] = new object; 
        }
        if (! isset($_SESSION['USER']))    { 
            $_SESSION['USER']    = new object; 
        }
    
        $SESSION = &$_SESSION['SESSION'];   // Makes them easier to reference
        $USER    = &$_SESSION['USER'];
    }
    else {
        $SESSION = NULL;
        $USER    = NULL;
    }

    if (defined('FULLME')) {     // Usually in command-line scripts like admin/cron.php
        $FULLME = FULLME;
        $ME = FULLME;
    } else {
        $FULLME = qualified_me();
        $ME = strip_querystring($FULLME);
    }

/// In VERY rare cases old PHP server bugs (it has been found on PHP 4.1.2 running 
/// as a CGI under IIS on Windows) may require that you uncomment the following:
//  session_register("USER");
//  session_register("SESSION");



/// Load up theme variables (colours etc)
    if (isset($_GET['theme'])) {
        if (confirm_sesskey()) {
            if (!detect_munged_arguments($_GET['theme'], 0) and file_exists($CFG->dirroot .'/theme/'. $_GET['theme'])) {
                $SESSION->theme = $_GET['theme'];
            }
        }
    }

    if (!isset($CFG->theme)) {
        $CFG->theme = 'standard';
    }

    theme_setup();  // Sets up theme global variables



/// Set language/locale of printed times.  If user has chosen a language that 
/// that is different from the site language, then use the locale specified 
/// in the language file.  Otherwise, if the admin hasn't specified a locale
/// then use the one from the default language.  Otherwise (and this is the 
/// majority of cases), use the stored locale specified by admin.

    if (isset($_GET['lang'])) {
        if (!detect_munged_arguments($lang, 0) and file_exists($CFG->dirroot .'/lang/'. $lang)) {
            $SESSION->lang = $lang;
            $SESSION->encoding = get_string('thischarset');
        }
    }
    if (empty($CFG->lang)) {
        $CFG->lang = "en";
    }

    moodle_setlocale();

    if (!empty($CFG->opentogoogle)) {
        if (empty($_SESSION['USER'])) {
            if (!empty($_SERVER['HTTP_USER_AGENT'])) {
                if (strpos($_SERVER['HTTP_USER_AGENT'], 'Googlebot') !== false ) {
                    $USER = guest_user();
                }
                if (strpos($_SERVER['HTTP_USER_AGENT'], 'google.com') !== false ) {
                    $USER = guest_user();
                }
            }
            if (empty($_SESSION['USER']) and !empty($_SERVER['HTTP_REFERER'])) {
                if (strpos($_SERVER['HTTP_REFERER'], 'google') !== false ) {
                    $USER = guest_user();
                }
            }
        }
    }

    if ($CFG->theme == 'standard') {    // Temporary measure to help with XHTML validation
        if (empty($_SESSION['USER'])) {      // Allow W3CValidator in as user called w3cvalidator (or guest)
            if ((strpos($_SERVER['HTTP_USER_AGENT'], 'W3C_Validator') !== false) or 
                (strpos($_SERVER['HTTP_USER_AGENT'], 'Cynthia') !== false )) {
                if ($USER = get_user_info_from_db("username", "w3cvalidator")) {
                    $USER->loggedin = true;
                    $USER->site = $CFG->wwwroot;
                    $USER->ignoresesskey = true;
                } else {
                    $USER = guest_user();
                }
            }
        }
    }

?>