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