google_forms/system/core/CodeIgniter.php

<?php

/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2019 - 2022, CodeIgniter Foundation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @package CodeIgniter
 * @author  EllisLab Dev Team
 * @copyright   Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
 * @copyright   Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/)
 * @copyright   Copyright (c) 2019 - 2022, CodeIgniter Foundation (https://codeigniter.com/)
 * @license https://opensource.org/licenses/MIT MIT License
 * @link    https://codeigniter.com
 * @since   Version 1.0.0
 * @filesource
 */

defined('BASEPATH') or exit('No direct script access allowed');

/**
 * System Initialization File
 *
 * Loads the base classes and executes the request.
 *
 * @package     CodeIgniter
 * @subpackage  CodeIgniter
 * @category    Front-controller
 * @author      EllisLab Dev Team
 * @link        https://codeigniter.com/userguide3/
 */

/**
 * CodeIgniter Version
 *
 * @var string
 *
 */
const CI_VERSION = '3.1.13';

/*
 * ------------------------------------------------------
 *  Load the framework constants
 * ------------------------------------------------------
 */
if (file_exists(APPPATH . 'config/' . ENVIRONMENT . '/constants.php')) {
    require_once(APPPATH . 'config/' . ENVIRONMENT . '/constants.php');
}

if (file_exists(APPPATH . 'config/constants.php')) {
    require_once(APPPATH . 'config/constants.php');
}

/*
 * ------------------------------------------------------
 *  Load the global functions
 * ------------------------------------------------------
 */
require_once(BASEPATH . 'core/Common.php');


/*
 * ------------------------------------------------------
 * Security procedures
 * ------------------------------------------------------
 */

if (! is_php('5.4')) {
    ini_set('magic_quotes_runtime', 0);

    if ((bool) ini_get('register_globals')) {
        $_protected = array(
            '_SERVER',
            '_GET',
            '_POST',
            '_FILES',
            '_REQUEST',
            '_SESSION',
            '_ENV',
            '_COOKIE',
            'GLOBALS',
            'HTTP_RAW_POST_DATA',
            'system_path',
            'application_folder',
            'view_folder',
            '_protected',
            '_registered'
        );

        $_registered = ini_get('variables_order');
        foreach (array('E' => '_ENV', 'G' => '_GET', 'P' => '_POST', 'C' => '_COOKIE', 'S' => '_SERVER') as $key => $superglobal) {
            if (strpos($_registered, $key) === false) {
                continue;
            }

            foreach (array_keys($$superglobal) as $var) {
                if (isset($GLOBALS[$var]) && ! in_array($var, $_protected, true)) {
                    $GLOBALS[$var] = null;
                }
            }
        }
    }
}


/*
 * ------------------------------------------------------
 *  Define a custom error handler so we can log PHP errors
 * ------------------------------------------------------
 */
set_error_handler('_error_handler');
set_exception_handler('_exception_handler');
register_shutdown_function('_shutdown_handler');

/*
 * ------------------------------------------------------
 *  Set the subclass_prefix
 * ------------------------------------------------------
 *
 * Normally the "subclass_prefix" is set in the config file.
 * The subclass prefix allows CI to know if a core class is
 * being extended via a library in the local application
 * "libraries" folder. Since CI allows config items to be
 * overridden via data set in the main index.php file,
 * before proceeding we need to know if a subclass_prefix
 * override exists. If so, we will set this value now,
 * before any classes are loaded
 * Note: Since the config file data is cached it doesn't
 * hurt to load it here.
 */
if (! empty($assign_to_config['subclass_prefix'])) {
    get_config(array('subclass_prefix' => $assign_to_config['subclass_prefix']));
}

/*
 * ------------------------------------------------------
 *  Should we use a Composer autoloader?
 * ------------------------------------------------------
 */
if ($composer_autoload = config_item('composer_autoload')) {
    if ($composer_autoload === true) {
        file_exists(APPPATH . 'vendor/autoload.php')
            ? require_once(APPPATH . 'vendor/autoload.php')
            : log_message('error', '$config[\'composer_autoload\'] is set to TRUE but ' . APPPATH . 'vendor/autoload.php was not found.');
    } elseif (file_exists($composer_autoload)) {
        require_once($composer_autoload);
    } else {
        log_message('error', 'Could not find the specified $config[\'composer_autoload\'] path: ' . $composer_autoload);
    }
}

/*
 * ------------------------------------------------------
 *  Start the timer... tick tock tick tock...
 * ------------------------------------------------------
 */
$BM = & load_class('Benchmark', 'core');
$BM->mark('total_execution_time_start');
$BM->mark('loading_time:_base_classes_start');

/*
 * ------------------------------------------------------
 *  Instantiate the hooks class
 * ------------------------------------------------------
 */
$EXT = & load_class('Hooks', 'core');

/*
 * ------------------------------------------------------
 *  Is there a "pre_system" hook?
 * ------------------------------------------------------
 */
$EXT->call_hook('pre_system');

/*
 * ------------------------------------------------------
 *  Instantiate the config class
 * ------------------------------------------------------
 *
 * Note: It is important that Config is loaded first as
 * most other classes depend on it either directly or by
 * depending on another class that uses it.
 *
 */
$CFG = & load_class('Config', 'core');

// Do we have any manually set config items in the index.php file?
if (isset($assign_to_config) && is_array($assign_to_config)) {
    foreach ($assign_to_config as $key => $value) {
        $CFG->set_item($key, $value);
    }
}

/*
 * ------------------------------------------------------
 * Important charset-related stuff
 * ------------------------------------------------------
 *
 * Configure mbstring and/or iconv if they are enabled
 * and set MB_ENABLED and ICONV_ENABLED constants, so
 * that we don't repeatedly do extension_loaded() or
 * function_exists() calls.
 *
 * Note: UTF-8 class depends on this. It used to be done
 * in it's constructor, but it's _not_ class-specific.
 *
 */
$charset = strtoupper(config_item('charset'));
ini_set('default_charset', $charset);

if (extension_loaded('mbstring')) {
    define('MB_ENABLED', true);
    // mbstring.internal_encoding is deprecated starting with PHP 5.6
    // and it's usage triggers E_DEPRECATED messages.
    @ini_set('mbstring.internal_encoding', $charset);
    // This is required for mb_convert_encoding() to strip invalid characters.
    // That's utilized by CI_Utf8, but it's also done for consistency with iconv.
    mb_substitute_character('none');
} else {
    define('MB_ENABLED', false);
}

// There's an ICONV_IMPL constant, but the PHP manual says that using
// iconv's predefined constants is "strongly discouraged".
if (extension_loaded('iconv')) {
    define('ICONV_ENABLED', true);
    // iconv.internal_encoding is deprecated starting with PHP 5.6
    // and it's usage triggers E_DEPRECATED messages.
    @ini_set('iconv.internal_encoding', $charset);
} else {
    define('ICONV_ENABLED', false);
}

if (is_php('5.6')) {
    ini_set('php.internal_encoding', $charset);
}

/*
 * ------------------------------------------------------
 *  Load compatibility features
 * ------------------------------------------------------
 */

require_once(BASEPATH . 'core/compat/mbstring.php');
require_once(BASEPATH . 'core/compat/hash.php');
require_once(BASEPATH . 'core/compat/password.php');
require_once(BASEPATH . 'core/compat/standard.php');

/*
 * ------------------------------------------------------
 *  Instantiate the UTF-8 class
 * ------------------------------------------------------
 */
$UNI = & load_class('Utf8', 'core');

/*
 * ------------------------------------------------------
 *  Instantiate the URI class
 * ------------------------------------------------------
 */
$URI = & load_class('URI', 'core');

/*
 * ------------------------------------------------------
 *  Instantiate the routing class and set the routing
 * ------------------------------------------------------
 */
$RTR = & load_class('Router', 'core', isset($routing) ? $routing : null);

/*
 * ------------------------------------------------------
 *  Instantiate the output class
 * ------------------------------------------------------
 */
$OUT = & load_class('Output', 'core');

/*
 * ------------------------------------------------------
 *	Is there a valid cache file? If so, we're done...
 * ------------------------------------------------------
 */
if ($EXT->call_hook('cache_override') === false && $OUT->_display_cache($CFG, $URI) === true) {
    exit;
}

/*
 * -----------------------------------------------------
 * Load the security class for xss and csrf support
 * -----------------------------------------------------
 */
$SEC = & load_class('Security', 'core');

/*
 * ------------------------------------------------------
 *  Load the Input class and sanitize globals
 * ------------------------------------------------------
 */
$IN = & load_class('Input', 'core');

/*
 * ------------------------------------------------------
 *  Load the Language class
 * ------------------------------------------------------
 */
$LANG = & load_class('Lang', 'core');

/*
 * ------------------------------------------------------
 *  Load the app controller and local controller
 * ------------------------------------------------------
 *
 */
// Load the base controller class
require_once BASEPATH . 'core/Controller.php';

/**
 * Reference to the CI_Controller method.
 *
 * Returns current CI instance object
 *
 * @return CI_Controller
 */
function &get_instance()
{
    return CI_Controller::get_instance();
}

if (file_exists(APPPATH . 'core/' . $CFG->config['subclass_prefix'] . 'Controller.php')) {
    require_once APPPATH . 'core/' . $CFG->config['subclass_prefix'] . 'Controller.php';
}

// Set a mark point for benchmarking
$BM->mark('loading_time:_base_classes_end');

/*
 * ------------------------------------------------------
 *  Sanity checks
 * ------------------------------------------------------
 *
 *  The Router class has already validated the request,
 *  leaving us with 3 options here:
 *
 *	1) an empty class name, if we reached the default
 *	   controller, but it didn't exist;
 *	2) a query string which doesn't go through a
 *	   file_exists() check
 *	3) a regular request for a non-existing page
 *
 *  We handle all of these as a 404 error.
 *
 *  Furthermore, none of the methods in the app controller
 *  or the loader class can be called via the URI, nor can
 *  controller methods that begin with an underscore.
 */

$e404 = false;
$class = ucfirst($RTR->class);
$method = $RTR->method;

if (empty($class) or ! file_exists(APPPATH . 'controllers/' . $RTR->directory . $class . '.php')) {
    $e404 = true;
} else {
    require_once(APPPATH . 'controllers/' . $RTR->directory . $class . '.php');

    if (! class_exists($class, false) or $method[0] === '_' or method_exists('CI_Controller', $method)) {
        $e404 = true;
    } elseif (method_exists($class, '_remap')) {
        $params = array($method, array_slice($URI->rsegments, 2));
        $method = '_remap';
    } elseif (! method_exists($class, $method)) {
        $e404 = true;
    }
    /**
     * DO NOT CHANGE THIS, NOTHING ELSE WORKS!
     *
     * - method_exists() returns true for non-public methods, which passes the previous elseif
     * - is_callable() returns false for PHP 4-style constructors, even if there's a __construct()
     * - method_exists($class, '__construct') won't work because CI_Controller::__construct() is inherited
     * - People will only complain if this doesn't work, even though it is documented that it shouldn't.
     *
     * ReflectionMethod::isConstructor() is the ONLY reliable check,
     * knowing which method will be executed as a constructor.
     */
    else {
        $reflection = new ReflectionMethod($class, $method);
        if (! $reflection->isPublic() or $reflection->isConstructor()) {
            $e404 = true;
        }
    }
}

if ($e404) {
    if (! empty($RTR->routes['404_override'])) {
        if (sscanf($RTR->routes['404_override'], '%[^/]/%s', $error_class, $error_method) !== 2) {
            $error_method = 'index';
        }

        $error_class = ucfirst($error_class);

        if (! class_exists($error_class, false)) {
            if (file_exists(APPPATH . 'controllers/' . $RTR->directory . $error_class . '.php')) {
                require_once(APPPATH . 'controllers/' . $RTR->directory . $error_class . '.php');
                $e404 = ! class_exists($error_class, false);
            }
            // Were we in a directory? If so, check for a global override
            elseif (! empty($RTR->directory) && file_exists(APPPATH . 'controllers/' . $error_class . '.php')) {
                require_once(APPPATH . 'controllers/' . $error_class . '.php');
                if (($e404 = ! class_exists($error_class, false)) === false) {
                    $RTR->directory = '';
                }
            }
        } else {
            $e404 = false;
        }
    }

    // Did we reset the $e404 flag? If so, set the rsegments, starting from index 1
    if (! $e404) {
        $class = $error_class;
        $method = $error_method;

        $URI->rsegments = array(
            1 => $class,
            2 => $method
        );
    } else {
        show_404($RTR->directory . $class . '/' . $method);
    }
}

if ($method !== '_remap') {
    $params = array_slice($URI->rsegments, 2);
}

/*
 * ------------------------------------------------------
 *  Is there a "pre_controller" hook?
 * ------------------------------------------------------
 */
$EXT->call_hook('pre_controller');

/*
 * ------------------------------------------------------
 *  Instantiate the requested controller
 * ------------------------------------------------------
 */
// Mark a start point so we can benchmark the controller
$BM->mark('controller_execution_time_( ' . $class . ' / ' . $method . ' )_start');

$CI = new $class();

/*
 * ------------------------------------------------------
 *  Is there a "post_controller_constructor" hook?
 * ------------------------------------------------------
 */
$EXT->call_hook('post_controller_constructor');

/*
 * ------------------------------------------------------
 *  Call the requested method
 * ------------------------------------------------------
 */
call_user_func_array(array(&$CI, $method), $params);

// Mark a benchmark end point
$BM->mark('controller_execution_time_( ' . $class . ' / ' . $method . ' )_end');

/*
 * ------------------------------------------------------
 *  Is there a "post_controller" hook?
 * ------------------------------------------------------
 */
$EXT->call_hook('post_controller');

/*
 * ------------------------------------------------------
 *  Send the final rendered output to the browser
 * ------------------------------------------------------
 */
if ($EXT->call_hook('display_override') === false) {
    $OUT->_display();
}

/*
 * ------------------------------------------------------
 *  Is there a "post_system" hook?
 * ------------------------------------------------------
 */
$EXT->call_hook('post_system');