moodle/lib/dmllib.php

<?php // $Id$

///////////////////////////////////////////////////////////////////////////
//                                                                       //
// NOTICE OF COPYRIGHT                                                   //
//                                                                       //
// Moodle - Modular Object-Oriented Dynamic Learning Environment         //
//          http://moodle.com                                            //
//                                                                       //
// Copyright (C) 1999 onwards Martin Dougiamas     http://dougiamas.com  //
//                                                                       //
// This program is free software; you can redistribute it and/or modify  //
// it under the terms of the GNU General Public License as published by  //
// the Free Software Foundation; either version 2 of the License, or     //
// (at your option) any later version.                                   //
//                                                                       //
// This program is distributed in the hope that it will be useful,       //
// but WITHOUT ANY WARRANTY; without even the implied warranty of        //
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         //
// GNU General Public License for more details:                          //
//                                                                       //
//          http://www.gnu.org/copyleft/gpl.html                         //
//                                                                       //
///////////////////////////////////////////////////////////////////////////

/// This library contains all the Data Manipulation Language (DML) functions
/// used to interact with the DB. All the dunctions in this library must be
/// generic and work against the major number of RDBMS possible. This is the
/// list of currently supported and tested DBs: mysql, postresql, mssql, oracle

/// This library is automatically included by Moodle core so you never need to
/// include it yourself.

/// For more info about the functions available in this library, please visit:
///     http://docs.moodle.org/en/DML_functions
/// (feel free to modify, improve and document such page, thanks!)

/// GLOBAL CONSTANTS /////////////////////////////////////////////////////////

/**
 * Bitmask, indicates only :name type parameters are supported by db backend.
 */
define('SQL_PARAMS_NAMED', 1);

/**
 * Bitmask, indicates only ? type parameters are supported by db backend.
 */
define('SQL_PARAMS_QM', 2);

/**
 * Bitmask, indicates only $1, $2.. type parameters are supported by db backend.
 */
define('SQL_PARAMS_DOLLAR', 4);


/**
 * Sets up global $DB moodle_database instance
 * @return void
 */
function setup_DB() {
    global $CFG, $DB;

    if (isset($DB)) {
        return;
    }

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

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

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

    if (!isset($CFG->dbpersist)) {
        $CFG->dbpersist = false;
    }

    if (!isset($CFG->dblibrary)) {
        $CFG->dblibrary = 'adodb';
    }

    if (!isset($CFG->dboptions)) {
        $CFG->dboptions = array();
    }

    if ($CFG->dblibrary == 'adodb') {
        $classname = $CFG->dbtype.'_adodb_moodle_database';
        require_once($CFG->libdir.'/dml/'.$classname.'.php');
        $DB = new $classname();

    } else {
        error('Not implemented db library yet: '.$CFG->dblibrary);
    }

    $CFG->dbfamily = $DB->get_dbfamily(); // TODO: BC only for now

    $driverstatus = $DB->driver_installed();

    if ($driverstatus !== true) {
        print_error('dbdriverproblem', 'error', '', $driverstatus);
    }

    if (debugging('', DEBUG_ALL)) {
        // catch errors
        ob_start();
    } else {
        $prevdebug = error_reporting(0);
    }
    if (!$DB->connect($CFG->dbhost, $CFG->dbuser, $CFG->dbpass, $CFG->dbname, $CFG->dbpersist, $CFG->prefix, $CFG->dboptions)) {
        if (debugging('', DEBUG_ALL)) {
            if ($dberr = ob_get_contents()) {
                $dberr = '<p><em>'.$dberr.'</em></p>';
            }
            ob_end_clean();
        } else {
            $dberr = '';
        }
        if (empty($CFG->noemailever) and !empty($CFG->emailconnectionerrorsto)) {
            @mail($CFG->emailconnectionerrorsto,
                  'WARNING: Database connection error: '.$CFG->wwwroot,
                  'Connection error: '.$CFG->wwwroot);
        }
        print_error('dbconnectionfailed', 'error', '', $dberr);
    }
    if (debugging('', DEBUG_ALL)) {
        ob_end_clean();
    } else {
        error_reporting($prevdebug);
    }

    return true;
}