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See Release Notes

  • Bug fixes for general core bugs in 4.3.x will end 7 October 2024 (12 months).
  • Bug fixes for security issues in 4.3.x will end 21 April 2025 (18 months).
  • PHP version: minimum PHP 8.0.0 Note: minimum PHP version has increased since Moodle 4.1. PHP 8.2.x is supported too.

Differences Between: [Versions 310 and 403] [Versions 311 and 403] [Versions 39 and 403] [Versions 400 and 403] [Versions 401 and 403] [Versions 402 and 403]

   1  <?php
   2  
   3  /*
   4   * This file is part of Composer.
   5   *
   6   * (c) Nils Adermann <naderman@naderman.de>
   7   *     Jordi Boggiano <j.boggiano@seld.be>
   8   *
   9   * For the full copyright and license information, please view the LICENSE
  10   * file that was distributed with this source code.
  11   */
  12  
  13  namespace Composer\Autoload;
  14  
  15  /**
  16   * ClassLoader implements a PSR-0, PSR-4 and classmap class loader.
  17   *
  18   *     $loader = new \Composer\Autoload\ClassLoader();
  19   *
  20   *     // register classes with namespaces
  21   *     $loader->add('Symfony\Component', __DIR__.'/component');
  22   *     $loader->add('Symfony',           __DIR__.'/framework');
  23   *
  24   *     // activate the autoloader
  25   *     $loader->register();
  26   *
  27   *     // to enable searching the include path (eg. for PEAR packages)
  28   *     $loader->setUseIncludePath(true);
  29   *
  30   * In this example, if you try to use a class in the Symfony\Component
  31   * namespace or one of its children (Symfony\Component\Console for instance),
  32   * the autoloader will first look for the class under the component/
  33   * directory, and it will then fallback to the framework/ directory if not
  34   * found before giving up.
  35   *
  36   * This class is loosely based on the Symfony UniversalClassLoader.
  37   *
  38   * @author Fabien Potencier <fabien@symfony.com>
  39   * @author Jordi Boggiano <j.boggiano@seld.be>
  40   * @see    https://www.php-fig.org/psr/psr-0/
  41   * @see    https://www.php-fig.org/psr/psr-4/
  42   */
  43  class ClassLoader
  44  {
  45      /** @var \Closure(string):void */
  46      private static $includeFile;
  47  
  48      /** @var ?string */
  49      private $vendorDir;
  50  
  51      // PSR-4
  52      /**
  53       * @var array[]
  54       * @psalm-var array<string, array<string, int>>
  55       */
  56      private $prefixLengthsPsr4 = array();
  57      /**
  58       * @var array[]
  59       * @psalm-var array<string, array<int, string>>
  60       */
  61      private $prefixDirsPsr4 = array();
  62      /**
  63       * @var array[]
  64       * @psalm-var array<string, string>
  65       */
  66      private $fallbackDirsPsr4 = array();
  67  
  68      // PSR-0
  69      /**
  70       * @var array[]
  71       * @psalm-var array<string, array<string, string[]>>
  72       */
  73      private $prefixesPsr0 = array();
  74      /**
  75       * @var array[]
  76       * @psalm-var array<string, string>
  77       */
  78      private $fallbackDirsPsr0 = array();
  79  
  80      /** @var bool */
  81      private $useIncludePath = false;
  82  
  83      /**
  84       * @var string[]
  85       * @psalm-var array<string, string>
  86       */
  87      private $classMap = array();
  88  
  89      /** @var bool */
  90      private $classMapAuthoritative = false;
  91  
  92      /**
  93       * @var bool[]
  94       * @psalm-var array<string, bool>
  95       */
  96      private $missingClasses = array();
  97  
  98      /** @var ?string */
  99      private $apcuPrefix;
 100  
 101      /**
 102       * @var self[]
 103       */
 104      private static $registeredLoaders = array();
 105  
 106      /**
 107       * @param ?string $vendorDir
 108       */
 109      public function __construct($vendorDir = null)
 110      {
 111          $this->vendorDir = $vendorDir;
 112          self::initializeIncludeClosure();
 113      }
 114  
 115      /**
 116       * @return string[]
 117       */
 118      public function getPrefixes()
 119      {
 120          if (!empty($this->prefixesPsr0)) {
 121              return call_user_func_array('array_merge', array_values($this->prefixesPsr0));
 122          }
 123  
 124          return array();
 125      }
 126  
 127      /**
 128       * @return array[]
 129       * @psalm-return array<string, array<int, string>>
 130       */
 131      public function getPrefixesPsr4()
 132      {
 133          return $this->prefixDirsPsr4;
 134      }
 135  
 136      /**
 137       * @return array[]
 138       * @psalm-return array<string, string>
 139       */
 140      public function getFallbackDirs()
 141      {
 142          return $this->fallbackDirsPsr0;
 143      }
 144  
 145      /**
 146       * @return array[]
 147       * @psalm-return array<string, string>
 148       */
 149      public function getFallbackDirsPsr4()
 150      {
 151          return $this->fallbackDirsPsr4;
 152      }
 153  
 154      /**
 155       * @return string[] Array of classname => path
 156       * @psalm-return array<string, string>
 157       */
 158      public function getClassMap()
 159      {
 160          return $this->classMap;
 161      }
 162  
 163      /**
 164       * @param string[] $classMap Class to filename map
 165       * @psalm-param array<string, string> $classMap
 166       *
 167       * @return void
 168       */
 169      public function addClassMap(array $classMap)
 170      {
 171          if ($this->classMap) {
 172              $this->classMap = array_merge($this->classMap, $classMap);
 173          } else {
 174              $this->classMap = $classMap;
 175          }
 176      }
 177  
 178      /**
 179       * Registers a set of PSR-0 directories for a given prefix, either
 180       * appending or prepending to the ones previously set for this prefix.
 181       *
 182       * @param string          $prefix  The prefix
 183       * @param string[]|string $paths   The PSR-0 root directories
 184       * @param bool            $prepend Whether to prepend the directories
 185       *
 186       * @return void
 187       */
 188      public function add($prefix, $paths, $prepend = false)
 189      {
 190          if (!$prefix) {
 191              if ($prepend) {
 192                  $this->fallbackDirsPsr0 = array_merge(
 193                      (array) $paths,
 194                      $this->fallbackDirsPsr0
 195                  );
 196              } else {
 197                  $this->fallbackDirsPsr0 = array_merge(
 198                      $this->fallbackDirsPsr0,
 199                      (array) $paths
 200                  );
 201              }
 202  
 203              return;
 204          }
 205  
 206          $first = $prefix[0];
 207          if (!isset($this->prefixesPsr0[$first][$prefix])) {
 208              $this->prefixesPsr0[$first][$prefix] = (array) $paths;
 209  
 210              return;
 211          }
 212          if ($prepend) {
 213              $this->prefixesPsr0[$first][$prefix] = array_merge(
 214                  (array) $paths,
 215                  $this->prefixesPsr0[$first][$prefix]
 216              );
 217          } else {
 218              $this->prefixesPsr0[$first][$prefix] = array_merge(
 219                  $this->prefixesPsr0[$first][$prefix],
 220                  (array) $paths
 221              );
 222          }
 223      }
 224  
 225      /**
 226       * Registers a set of PSR-4 directories for a given namespace, either
 227       * appending or prepending to the ones previously set for this namespace.
 228       *
 229       * @param string          $prefix  The prefix/namespace, with trailing '\\'
 230       * @param string[]|string $paths   The PSR-4 base directories
 231       * @param bool            $prepend Whether to prepend the directories
 232       *
 233       * @throws \InvalidArgumentException
 234       *
 235       * @return void
 236       */
 237      public function addPsr4($prefix, $paths, $prepend = false)
 238      {
 239          if (!$prefix) {
 240              // Register directories for the root namespace.
 241              if ($prepend) {
 242                  $this->fallbackDirsPsr4 = array_merge(
 243                      (array) $paths,
 244                      $this->fallbackDirsPsr4
 245                  );
 246              } else {
 247                  $this->fallbackDirsPsr4 = array_merge(
 248                      $this->fallbackDirsPsr4,
 249                      (array) $paths
 250                  );
 251              }
 252          } elseif (!isset($this->prefixDirsPsr4[$prefix])) {
 253              // Register directories for a new namespace.
 254              $length = strlen($prefix);
 255              if ('\\' !== $prefix[$length - 1]) {
 256                  throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");
 257              }
 258              $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;
 259              $this->prefixDirsPsr4[$prefix] = (array) $paths;
 260          } elseif ($prepend) {
 261              // Prepend directories for an already registered namespace.
 262              $this->prefixDirsPsr4[$prefix] = array_merge(
 263                  (array) $paths,
 264                  $this->prefixDirsPsr4[$prefix]
 265              );
 266          } else {
 267              // Append directories for an already registered namespace.
 268              $this->prefixDirsPsr4[$prefix] = array_merge(
 269                  $this->prefixDirsPsr4[$prefix],
 270                  (array) $paths
 271              );
 272          }
 273      }
 274  
 275      /**
 276       * Registers a set of PSR-0 directories for a given prefix,
 277       * replacing any others previously set for this prefix.
 278       *
 279       * @param string          $prefix The prefix
 280       * @param string[]|string $paths  The PSR-0 base directories
 281       *
 282       * @return void
 283       */
 284      public function set($prefix, $paths)
 285      {
 286          if (!$prefix) {
 287              $this->fallbackDirsPsr0 = (array) $paths;
 288          } else {
 289              $this->prefixesPsr0[$prefix[0]][$prefix] = (array) $paths;
 290          }
 291      }
 292  
 293      /**
 294       * Registers a set of PSR-4 directories for a given namespace,
 295       * replacing any others previously set for this namespace.
 296       *
 297       * @param string          $prefix The prefix/namespace, with trailing '\\'
 298       * @param string[]|string $paths  The PSR-4 base directories
 299       *
 300       * @throws \InvalidArgumentException
 301       *
 302       * @return void
 303       */
 304      public function setPsr4($prefix, $paths)
 305      {
 306          if (!$prefix) {
 307              $this->fallbackDirsPsr4 = (array) $paths;
 308          } else {
 309              $length = strlen($prefix);
 310              if ('\\' !== $prefix[$length - 1]) {
 311                  throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");
 312              }
 313              $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;
 314              $this->prefixDirsPsr4[$prefix] = (array) $paths;
 315          }
 316      }
 317  
 318      /**
 319       * Turns on searching the include path for class files.
 320       *
 321       * @param bool $useIncludePath
 322       *
 323       * @return void
 324       */
 325      public function setUseIncludePath($useIncludePath)
 326      {
 327          $this->useIncludePath = $useIncludePath;
 328      }
 329  
 330      /**
 331       * Can be used to check if the autoloader uses the include path to check
 332       * for classes.
 333       *
 334       * @return bool
 335       */
 336      public function getUseIncludePath()
 337      {
 338          return $this->useIncludePath;
 339      }
 340  
 341      /**
 342       * Turns off searching the prefix and fallback directories for classes
 343       * that have not been registered with the class map.
 344       *
 345       * @param bool $classMapAuthoritative
 346       *
 347       * @return void
 348       */
 349      public function setClassMapAuthoritative($classMapAuthoritative)
 350      {
 351          $this->classMapAuthoritative = $classMapAuthoritative;
 352      }
 353  
 354      /**
 355       * Should class lookup fail if not found in the current class map?
 356       *
 357       * @return bool
 358       */
 359      public function isClassMapAuthoritative()
 360      {
 361          return $this->classMapAuthoritative;
 362      }
 363  
 364      /**
 365       * APCu prefix to use to cache found/not-found classes, if the extension is enabled.
 366       *
 367       * @param string|null $apcuPrefix
 368       *
 369       * @return void
 370       */
 371      public function setApcuPrefix($apcuPrefix)
 372      {
 373          $this->apcuPrefix = function_exists('apcu_fetch') && filter_var(ini_get('apc.enabled'), FILTER_VALIDATE_BOOLEAN) ? $apcuPrefix : null;
 374      }
 375  
 376      /**
 377       * The APCu prefix in use, or null if APCu caching is not enabled.
 378       *
 379       * @return string|null
 380       */
 381      public function getApcuPrefix()
 382      {
 383          return $this->apcuPrefix;
 384      }
 385  
 386      /**
 387       * Registers this instance as an autoloader.
 388       *
 389       * @param bool $prepend Whether to prepend the autoloader or not
 390       *
 391       * @return void
 392       */
 393      public function register($prepend = false)
 394      {
 395          spl_autoload_register(array($this, 'loadClass'), true, $prepend);
 396  
 397          if (null === $this->vendorDir) {
 398              return;
 399          }
 400  
 401          if ($prepend) {
 402              self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
 403          } else {
 404              unset(self::$registeredLoaders[$this->vendorDir]);
 405              self::$registeredLoaders[$this->vendorDir] = $this;
 406          }
 407      }
 408  
 409      /**
 410       * Unregisters this instance as an autoloader.
 411       *
 412       * @return void
 413       */
 414      public function unregister()
 415      {
 416          spl_autoload_unregister(array($this, 'loadClass'));
 417  
 418          if (null !== $this->vendorDir) {
 419              unset(self::$registeredLoaders[$this->vendorDir]);
 420          }
 421      }
 422  
 423      /**
 424       * Loads the given class or interface.
 425       *
 426       * @param  string    $class The name of the class
 427       * @return true|null True if loaded, null otherwise
 428       */
 429      public function loadClass($class)
 430      {
 431          if ($file = $this->findFile($class)) {
 432              $includeFile = self::$includeFile;
 433              $includeFile($file);
 434  
 435              return true;
 436          }
 437  
 438          return null;
 439      }
 440  
 441      /**
 442       * Finds the path to the file where the class is defined.
 443       *
 444       * @param string $class The name of the class
 445       *
 446       * @return string|false The path if found, false otherwise
 447       */
 448      public function findFile($class)
 449      {
 450          // class map lookup
 451          if (isset($this->classMap[$class])) {
 452              return $this->classMap[$class];
 453          }
 454          if ($this->classMapAuthoritative || isset($this->missingClasses[$class])) {
 455              return false;
 456          }
 457          if (null !== $this->apcuPrefix) {
 458              $file = apcu_fetch($this->apcuPrefix.$class, $hit);
 459              if ($hit) {
 460                  return $file;
 461              }
 462          }
 463  
 464          $file = $this->findFileWithExtension($class, '.php');
 465  
 466          // Search for Hack files if we are running on HHVM
 467          if (false === $file && defined('HHVM_VERSION')) {
 468              $file = $this->findFileWithExtension($class, '.hh');
 469          }
 470  
 471          if (null !== $this->apcuPrefix) {
 472              apcu_add($this->apcuPrefix.$class, $file);
 473          }
 474  
 475          if (false === $file) {
 476              // Remember that this class does not exist.
 477              $this->missingClasses[$class] = true;
 478          }
 479  
 480          return $file;
 481      }
 482  
 483      /**
 484       * Returns the currently registered loaders indexed by their corresponding vendor directories.
 485       *
 486       * @return self[]
 487       */
 488      public static function getRegisteredLoaders()
 489      {
 490          return self::$registeredLoaders;
 491      }
 492  
 493      /**
 494       * @param  string       $class
 495       * @param  string       $ext
 496       * @return string|false
 497       */
 498      private function findFileWithExtension($class, $ext)
 499      {
 500          // PSR-4 lookup
 501          $logicalPathPsr4 = strtr($class, '\\', DIRECTORY_SEPARATOR) . $ext;
 502  
 503          $first = $class[0];
 504          if (isset($this->prefixLengthsPsr4[$first])) {
 505              $subPath = $class;
 506              while (false !== $lastPos = strrpos($subPath, '\\')) {
 507                  $subPath = substr($subPath, 0, $lastPos);
 508                  $search = $subPath . '\\';
 509                  if (isset($this->prefixDirsPsr4[$search])) {
 510                      $pathEnd = DIRECTORY_SEPARATOR . substr($logicalPathPsr4, $lastPos + 1);
 511                      foreach ($this->prefixDirsPsr4[$search] as $dir) {
 512                          if (file_exists($file = $dir . $pathEnd)) {
 513                              return $file;
 514                          }
 515                      }
 516                  }
 517              }
 518          }
 519  
 520          // PSR-4 fallback dirs
 521          foreach ($this->fallbackDirsPsr4 as $dir) {
 522              if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr4)) {
 523                  return $file;
 524              }
 525          }
 526  
 527          // PSR-0 lookup
 528          if (false !== $pos = strrpos($class, '\\')) {
 529              // namespaced class name
 530              $logicalPathPsr0 = substr($logicalPathPsr4, 0, $pos + 1)
 531                  . strtr(substr($logicalPathPsr4, $pos + 1), '_', DIRECTORY_SEPARATOR);
 532          } else {
 533              // PEAR-like class name
 534              $logicalPathPsr0 = strtr($class, '_', DIRECTORY_SEPARATOR) . $ext;
 535          }
 536  
 537          if (isset($this->prefixesPsr0[$first])) {
 538              foreach ($this->prefixesPsr0[$first] as $prefix => $dirs) {
 539                  if (0 === strpos($class, $prefix)) {
 540                      foreach ($dirs as $dir) {
 541                          if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {
 542                              return $file;
 543                          }
 544                      }
 545                  }
 546              }
 547          }
 548  
 549          // PSR-0 fallback dirs
 550          foreach ($this->fallbackDirsPsr0 as $dir) {
 551              if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {
 552                  return $file;
 553              }
 554          }
 555  
 556          // PSR-0 include paths.
 557          if ($this->useIncludePath && $file = stream_resolve_include_path($logicalPathPsr0)) {
 558              return $file;
 559          }
 560  
 561          return false;
 562      }
 563  
 564      /**
 565       * @return void
 566       */
 567      private static function initializeIncludeClosure()
 568      {
 569          if (self::$includeFile !== null) {
 570              return;
 571          }
 572  
 573          /**
 574           * Scope isolated include.
 575           *
 576           * Prevents access to $this/self from included files.
 577           *
 578           * @param  string $file
 579           * @return void
 580           */
 581          self::$includeFile = \Closure::bind(static function($file) {
 582              include $file;
 583          }, null, null);
 584      }
 585  }