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
13namespace 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 */
43class ClassLoader
44{
45 /** @var \Closure(string):void */
46 private static $includeFile;
47
48 /** @var string|null */
49 private $vendorDir;
50
51 // PSR-4
52 /**
53 * @var array<string, array<string, int>>
54 */
55 private $prefixLengthsPsr4 = array();
56 /**
57 * @var array<string, list<string>>
58 */
59 private $prefixDirsPsr4 = array();
60 /**
61 * @var list<string>
62 */
63 private $fallbackDirsPsr4 = array();
64
65 // PSR-0
66 /**
67 * List of PSR-0 prefixes
68 *
69 * Structured as array('F (first letter)' => array('Foo\Bar (full prefix)' => array('path', 'path2')))
70 *
71 * @var array<string, array<string, list<string>>>
72 */
73 private $prefixesPsr0 = array();
74 /**
75 * @var list<string>
76 */
77 private $fallbackDirsPsr0 = array();
78
79 /** @var bool */
80 private $useIncludePath = false;
81
82 /**
83 * @var array<string, string>
84 */
85 private $classMap = array();
86
87 /** @var bool */
88 private $classMapAuthoritative = false;
89
90 /**
91 * @var array<string, bool>
92 */
93 private $missingClasses = array();
94
95 /** @var string|null */
96 private $apcuPrefix;
97
98 /**
99 * @var array<string, self>
100 */
101 private static $registeredLoaders = array();
102
103 /**
104 * @param string|null $vendorDir
105 */
106 public function __construct($vendorDir = null)
107 {
108 $this->vendorDir = $vendorDir;
109 self::initializeIncludeClosure();
110 }
111
112 /**
113 * @return array<string, list<string>>
114 */
115 public function getPrefixes()
116 {
117 if (!empty($this->prefixesPsr0)) {
118 return call_user_func_array('array_merge', array_values($this->prefixesPsr0));
119 }
120
121 return array();
122 }
123
124 /**
125 * @return array<string, list<string>>
126 */
127 public function getPrefixesPsr4()
128 {
129 return $this->prefixDirsPsr4;
130 }
131
132 /**
133 * @return list<string>
134 */
135 public function getFallbackDirs()
136 {
137 return $this->fallbackDirsPsr0;
138 }
139
140 /**
141 * @return list<string>
142 */
143 public function getFallbackDirsPsr4()
144 {
145 return $this->fallbackDirsPsr4;
146 }
147
148 /**
149 * @return array<string, string> Array of classname => path
150 */
151 public function getClassMap()
152 {
153 return $this->classMap;
154 }
155
156 /**
157 * @param array<string, string> $classMap Class to filename map
158 *
159 * @return void
160 */
161 public function addClassMap(array $classMap)
162 {
163 if ($this->classMap) {
164 $this->classMap = array_merge($this->classMap, $classMap);
165 } else {
166 $this->classMap = $classMap;
167 }
168 }
169
170 /**
171 * Registers a set of PSR-0 directories for a given prefix, either
172 * appending or prepending to the ones previously set for this prefix.
173 *
174 * @param string $prefix The prefix
175 * @param list<string>|string $paths The PSR-0 root directories
176 * @param bool $prepend Whether to prepend the directories
177 *
178 * @return void
179 */
180 public function add($prefix, $paths, $prepend = false)
181 {
182 $paths = (array) $paths;
183 if (!$prefix) {
184 if ($prepend) {
185 $this->fallbackDirsPsr0 = array_merge(
186 $paths,
187 $this->fallbackDirsPsr0
188 );
189 } else {
190 $this->fallbackDirsPsr0 = array_merge(
191 $this->fallbackDirsPsr0,
192 $paths
193 );
194 }
195
196 return;
197 }
198
199 $first = $prefix[0];
200 if (!isset($this->prefixesPsr0[$first][$prefix])) {
201 $this->prefixesPsr0[$first][$prefix] = $paths;
202
203 return;
204 }
205 if ($prepend) {
206 $this->prefixesPsr0[$first][$prefix] = array_merge(
207 $paths,
208 $this->prefixesPsr0[$first][$prefix]
209 );
210 } else {
211 $this->prefixesPsr0[$first][$prefix] = array_merge(
212 $this->prefixesPsr0[$first][$prefix],
213 $paths
214 );
215 }
216 }
217
218 /**
219 * Registers a set of PSR-4 directories for a given namespace, either
220 * appending or prepending to the ones previously set for this namespace.
221 *
222 * @param string $prefix The prefix/namespace, with trailing '\\'
223 * @param list<string>|string $paths The PSR-4 base directories
224 * @param bool $prepend Whether to prepend the directories
225 *
226 * @throws \InvalidArgumentException
227 *
228 * @return void
229 */
230 public function addPsr4($prefix, $paths, $prepend = false)
231 {
232 $paths = (array) $paths;
233 if (!$prefix) {
234 // Register directories for the root namespace.
235 if ($prepend) {
236 $this->fallbackDirsPsr4 = array_merge(
237 $paths,
238 $this->fallbackDirsPsr4
239 );
240 } else {
241 $this->fallbackDirsPsr4 = array_merge(
242 $this->fallbackDirsPsr4,
243 $paths
244 );
245 }
246 } elseif (!isset($this->prefixDirsPsr4[$prefix])) {
247 // Register directories for a new namespace.
248 $length = strlen($prefix);
249 if ('\\' !== $prefix[$length - 1]) {
250 throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");
251 }
252 $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;
253 $this->prefixDirsPsr4[$prefix] = $paths;
254 } elseif ($prepend) {
255 // Prepend directories for an already registered namespace.
256 $this->prefixDirsPsr4[$prefix] = array_merge(
257 $paths,
258 $this->prefixDirsPsr4[$prefix]
259 );
260 } else {
261 // Append directories for an already registered namespace.
262 $this->prefixDirsPsr4[$prefix] = array_merge(
263 $this->prefixDirsPsr4[$prefix],
264 $paths
265 );
266 }
267 }
268
269 /**
270 * Registers a set of PSR-0 directories for a given prefix,
271 * replacing any others previously set for this prefix.
272 *
273 * @param string $prefix The prefix
274 * @param list<string>|string $paths The PSR-0 base directories
275 *
276 * @return void
277 */
278 public function set($prefix, $paths)
279 {
280 if (!$prefix) {
281 $this->fallbackDirsPsr0 = (array) $paths;
282 } else {
283 $this->prefixesPsr0[$prefix[0]][$prefix] = (array) $paths;
284 }
285 }
286
287 /**
288 * Registers a set of PSR-4 directories for a given namespace,
289 * replacing any others previously set for this namespace.
290 *
291 * @param string $prefix The prefix/namespace, with trailing '\\'
292 * @param list<string>|string $paths The PSR-4 base directories
293 *
294 * @throws \InvalidArgumentException
295 *
296 * @return void
297 */
298 public function setPsr4($prefix, $paths)
299 {
300 if (!$prefix) {
301 $this->fallbackDirsPsr4 = (array) $paths;
302 } else {
303 $length = strlen($prefix);
304 if ('\\' !== $prefix[$length - 1]) {
305 throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");
306 }
307 $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;
308 $this->prefixDirsPsr4[$prefix] = (array) $paths;
309 }
310 }
311
312 /**
313 * Turns on searching the include path for class files.
314 *
315 * @param bool $useIncludePath
316 *
317 * @return void
318 */
319 public function setUseIncludePath($useIncludePath)
320 {
321 $this->useIncludePath = $useIncludePath;
322 }
323
324 /**
325 * Can be used to check if the autoloader uses the include path to check
326 * for classes.
327 *
328 * @return bool
329 */
330 public function getUseIncludePath()
331 {
332 return $this->useIncludePath;
333 }
334
335 /**
336 * Turns off searching the prefix and fallback directories for classes
337 * that have not been registered with the class map.
338 *
339 * @param bool $classMapAuthoritative
340 *
341 * @return void
342 */
343 public function setClassMapAuthoritative($classMapAuthoritative)
344 {
345 $this->classMapAuthoritative = $classMapAuthoritative;
346 }
347
348 /**
349 * Should class lookup fail if not found in the current class map?
350 *
351 * @return bool
352 */
353 public function isClassMapAuthoritative()
354 {
355 return $this->classMapAuthoritative;
356 }
357
358 /**
359 * APCu prefix to use to cache found/not-found classes, if the extension is enabled.
360 *
361 * @param string|null $apcuPrefix
362 *
363 * @return void
364 */
365 public function setApcuPrefix($apcuPrefix)
366 {
367 $this->apcuPrefix = function_exists('apcu_fetch') && filter_var(ini_get('apc.enabled'), FILTER_VALIDATE_BOOLEAN) ? $apcuPrefix : null;
368 }
369
370 /**
371 * The APCu prefix in use, or null if APCu caching is not enabled.
372 *
373 * @return string|null
374 */
375 public function getApcuPrefix()
376 {
377 return $this->apcuPrefix;
378 }
379
380 /**
381 * Registers this instance as an autoloader.
382 *
383 * @param bool $prepend Whether to prepend the autoloader or not
384 *
385 * @return void
386 */
387 public function register($prepend = false)
388 {
389 spl_autoload_register(array($this, 'loadClass'), true, $prepend);
390
391 if (null === $this->vendorDir) {
392 return;
393 }
394
395 if ($prepend) {
396 self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
397 } else {
398 unset(self::$registeredLoaders[$this->vendorDir]);
399 self::$registeredLoaders[$this->vendorDir] = $this;
400 }
401 }
402
403 /**
404 * Unregisters this instance as an autoloader.
405 *
406 * @return void
407 */
408 public function unregister()
409 {
410 spl_autoload_unregister(array($this, 'loadClass'));
411
412 if (null !== $this->vendorDir) {
413 unset(self::$registeredLoaders[$this->vendorDir]);
414 }
415 }
416
417 /**
418 * Loads the given class or interface.
419 *
420 * @param string $class The name of the class
421 * @return true|null True if loaded, null otherwise
422 */
423 public function loadClass($class)
424 {
425 if ($file = $this->findFile($class)) {
426 $includeFile = self::$includeFile;
427 $includeFile($file);
428
429 return true;
430 }
431
432 return null;
433 }
434
435 /**
436 * Finds the path to the file where the class is defined.
437 *
438 * @param string $class The name of the class
439 *
440 * @return string|false The path if found, false otherwise
441 */
442 public function findFile($class)
443 {
444 // class map lookup
445 if (isset($this->classMap[$class])) {
446 return $this->classMap[$class];
447 }
448 if ($this->classMapAuthoritative || isset($this->missingClasses[$class])) {
449 return false;
450 }
451 if (null !== $this->apcuPrefix) {
452 $file = apcu_fetch($this->apcuPrefix.$class, $hit);
453 if ($hit) {
454 return $file;
455 }
456 }
457
458 $file = $this->findFileWithExtension($class, '.php');
459
460 // Search for Hack files if we are running on HHVM
461 if (false === $file && defined('HHVM_VERSION')) {
462 $file = $this->findFileWithExtension($class, '.hh');
463 }
464
465 if (null !== $this->apcuPrefix) {
466 apcu_add($this->apcuPrefix.$class, $file);
467 }
468
469 if (false === $file) {
470 // Remember that this class does not exist.
471 $this->missingClasses[$class] = true;
472 }
473
474 return $file;
475 }
476
477 /**
478 * Returns the currently registered loaders keyed by their corresponding vendor directories.
479 *
480 * @return array<string, self>
481 */
482 public static function getRegisteredLoaders()
483 {
484 return self::$registeredLoaders;
485 }
486
487 /**
488 * @param string $class
489 * @param string $ext
490 * @return string|false
491 */
492 private function findFileWithExtension($class, $ext)
493 {
494 // PSR-4 lookup
495 $logicalPathPsr4 = strtr($class, '\\', DIRECTORY_SEPARATOR) . $ext;
496
497 $first = $class[0];
498 if (isset($this->prefixLengthsPsr4[$first])) {
499 $subPath = $class;
500 while (false !== $lastPos = strrpos($subPath, '\\')) {
501 $subPath = substr($subPath, 0, $lastPos);
502 $search = $subPath . '\\';
503 if (isset($this->prefixDirsPsr4[$search])) {
504 $pathEnd = DIRECTORY_SEPARATOR . substr($logicalPathPsr4, $lastPos + 1);
505 foreach ($this->prefixDirsPsr4[$search] as $dir) {
506 if (file_exists($file = $dir . $pathEnd)) {
507 return $file;
508 }
509 }
510 }
511 }
512 }
513
514 // PSR-4 fallback dirs
515 foreach ($this->fallbackDirsPsr4 as $dir) {
516 if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr4)) {
517 return $file;
518 }
519 }
520
521 // PSR-0 lookup
522 if (false !== $pos = strrpos($class, '\\')) {
523 // namespaced class name
524 $logicalPathPsr0 = substr($logicalPathPsr4, 0, $pos + 1)
525 . strtr(substr($logicalPathPsr4, $pos + 1), '_', DIRECTORY_SEPARATOR);
526 } else {
527 // PEAR-like class name
528 $logicalPathPsr0 = strtr($class, '_', DIRECTORY_SEPARATOR) . $ext;
529 }
530
531 if (isset($this->prefixesPsr0[$first])) {
532 foreach ($this->prefixesPsr0[$first] as $prefix => $dirs) {
533 if (0 === strpos($class, $prefix)) {
534 foreach ($dirs as $dir) {
535 if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {
536 return $file;
537 }
538 }
539 }
540 }
541 }
542
543 // PSR-0 fallback dirs
544 foreach ($this->fallbackDirsPsr0 as $dir) {
545 if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {
546 return $file;
547 }
548 }
549
550 // PSR-0 include paths.
551 if ($this->useIncludePath && $file = stream_resolve_include_path($logicalPathPsr0)) {
552 return $file;
553 }
554
555 return false;
556 }
557
558 /**
559 * @return void
560 */
561 private static function initializeIncludeClosure()
562 {
563 if (self::$includeFile !== null) {
564 return;
565 }
566
567 /**
568 * Scope isolated include.
569 *
570 * Prevents access to $this/self from included files.
571 *
572 * @param string $file
573 * @return void
574 */
575 self::$includeFile = \Closure::bind(static function($file) {
576 include $file;
577 }, null, null);
578 }
579}
580