includes/AutoLoader.php

   1 <?php
   2 /**
   3  * This defines autoloading handler for whole MediaWiki framework
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 /**
  24  * Locations of core classes
  25  * Extension classes are specified with $wgAutoloadClasses
  26  * This array is a global instead of a static member of AutoLoader to work around a bug in APC
  27  * This array is now generated by maintenance/generateLocalAutoload.php
  28  */
  29 require_once __DIR__ . '/../autoload.php';
  30
  31 class AutoLoader {
  32         static protected $autoloadLocalClassesLower = null;
  33
  34         /**
  35          * autoload - take a class name and attempt to load it
  36          *
  37          * @param string $className Name of class we're looking for.
  38          */
  39         static function autoload( $className ) {
  40                 global $wgAutoloadClasses, $wgAutoloadLocalClasses,
  41                         $wgAutoloadAttemptLowercase;
  42
  43                 // Workaround for PHP bug <https://bugs.php.net/bug.php?id=49143> (5.3.2. is broken, it's
  44                 // fixed in 5.3.6). Strip leading backslashes from class names. When namespaces are used,
  45                 // leading backslashes are used to indicate the top-level namespace, e.g. \foo\Bar. When
  46                 // used like this in the code, the leading backslash isn't passed to the auto-loader
  47                 // ($className would be 'foo\Bar'). However, if a class is accessed using a string instead
  48                 // of a class literal (e.g. $class = '\foo\Bar'; new $class()), then some versions of PHP
  49                 // do not strip the leading backlash in this case, causing autoloading to fail.
  50                 $className = ltrim( $className, '\\' );
  51
  52                 $filename = false;
  53
  54                 if ( isset( $wgAutoloadLocalClasses[$className] ) ) {
  55                         $filename = $wgAutoloadLocalClasses[$className];
  56                 } elseif ( isset( $wgAutoloadClasses[$className] ) ) {
  57                         $filename = $wgAutoloadClasses[$className];
  58                 } elseif ( $wgAutoloadAttemptLowercase ) {
  59                         /*
  60                          * Try a different capitalisation.
  61                          *
  62                          * PHP 4 objects are always serialized with the classname coerced to lowercase,
  63                          * and we are plagued with several legacy uses created by MediaWiki < 1.5, see
  64                          * https://wikitech.wikimedia.org/wiki/Text_storage_data
  65                          */
  66                         $lowerClass = strtolower( $className );
  67
  68                         if ( self::$autoloadLocalClassesLower === null ) {
  69                                 self::$autoloadLocalClassesLower = array_change_key_case( $wgAutoloadLocalClasses, CASE_LOWER );
  70                         }
  71
  72                         if ( isset( self::$autoloadLocalClassesLower[$lowerClass] ) ) {
  73                                 if ( function_exists( 'wfDebugLog' ) ) {
  74                                         wfDebugLog( 'autoloader', "Class {$className} was loaded using incorrect case" );
  75                                 }
  76                                 $filename = self::$autoloadLocalClassesLower[$lowerClass];
  77                         }
  78                 }
  79
  80                 if ( !$filename ) {
  81                         // Class not found; let the next autoloader try to find it
  82                         return;
  83                 }
  84
  85                 // Make an absolute path, this improves performance by avoiding some stat calls
  86                 if ( substr( $filename, 0, 1 ) != '/' && substr( $filename, 1, 1 ) != ':' ) {
  87                         global $IP;
  88                         $filename = "$IP/$filename";
  89                 }
  90
  91                 require $filename;
  92         }
  93
  94         /**
  95          * Force a class to be run through the autoloader, helpful for things like
  96          * Sanitizer that have define()s outside of their class definition. Of course
  97          * this wouldn't be necessary if everything in MediaWiki was class-based. Sigh.
  98          *
  99          * @param string $class
 100          * @return bool Return the results of class_exists() so we know if we were successful
 101          */
 102         static function loadClass( $class ) {
 103                 return class_exists( $class );
 104         }
 105
 106         /**
 107          * Method to clear the protected class property $autoloadLocalClassesLower.
 108          * Used in tests.
 109          */
 110         static function resetAutoloadLocalClassesLower() {
 111                 self::$autoloadLocalClassesLower = null;
 112         }
 113 }
 114
 115 spl_autoload_register( array( 'AutoLoader', 'autoload' ) );