wikimedia / mediawiki

includes/AutoLoader.php

<?php

For compatibility and reusability of your code, PSR1 recommends that a file should introduce either new symbols (like classes, functions, etc.) or have side-effects (like outputting something, or including other files), but not both at the same time. The first symbol is defined on line 30 and the first side effect is on line 28.

/**
 * This defines autoloading handler for whole MediaWiki framework
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 */

/**
 * Locations of core classes
 * Extension classes are specified with $wgAutoloadClasses
 * This array is a global instead of a static member of AutoLoader to work around a bug in APC
 */
require_once __DIR__ . '/../autoload.php';

class AutoLoader {
	static protected $autoloadLocalClassesLower = null;

	/**
	 * autoload - take a class name and attempt to load it
	 *
	 * @param string $className Name of class we're looking for.
	 */
	static function autoload( $className ) {
		global $wgAutoloadClasses, $wgAutoloadLocalClasses,
			$wgAutoloadAttemptLowercase;

		$filename = false;

		if ( isset( $wgAutoloadLocalClasses[$className] ) ) {
			$filename = $wgAutoloadLocalClasses[$className];
		} elseif ( isset( $wgAutoloadClasses[$className] ) ) {
			$filename = $wgAutoloadClasses[$className];
		} elseif ( $wgAutoloadAttemptLowercase ) {
			/*
			 * Try a different capitalisation.
			 *
			 * PHP 4 objects are always serialized with the classname coerced to lowercase,
			 * and we are plagued with several legacy uses created by MediaWiki < 1.5, see
			 * https://wikitech.wikimedia.org/wiki/Text_storage_data
			 */
			$lowerClass = strtolower( $className );

			if ( self::$autoloadLocalClassesLower === null ) {
				self::$autoloadLocalClassesLower = array_change_key_case( $wgAutoloadLocalClasses, CASE_LOWER );
			}

			if ( isset( self::$autoloadLocalClassesLower[$lowerClass] ) ) {
				if ( function_exists( 'wfDebugLog' ) ) {
					wfDebugLog( 'autoloader', "Class {$className} was loaded using incorrect case" );
				}
				$filename = self::$autoloadLocalClassesLower[$lowerClass];
			}
		}

		if ( !$filename ) {
			// Class not found; let the next autoloader try to find it
			return;
		}

		// Make an absolute path, this improves performance by avoiding some stat calls
		if ( substr( $filename, 0, 1 ) != '/' && substr( $filename, 1, 1 ) != ':' ) {
			global $IP;
			$filename = "$IP/$filename";
		}

		require $filename;
	}

	/**
	 * Method to clear the protected class property $autoloadLocalClassesLower.
	 * Used in tests.
	 */
	static function resetAutoloadLocalClassesLower() {
		self::$autoloadLocalClassesLower = null;
	}
}

spl_autoload_register( [ 'AutoLoader', 'autoload' ] );