File size: 4.77Kb
<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <[email protected]>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Config\Resource;
/**
* ClassExistenceResource represents a class existence.
* Freshness is only evaluated against resource existence.
*
* The resource must be a fully-qualified class name.
*
* @author Fabien Potencier <[email protected]>
*/
class ClassExistenceResource implements SelfCheckingResourceInterface, \Serializable
{
private $resource;
private $exists;
private static $autoloadLevel = 0;
private static $autoloadedClass;
private static $existsCache = array();
/**
* @param string $resource The fully-qualified class name
* @param bool|null $exists Boolean when the existency check has already been done
*/
public function __construct(string $resource, bool $exists = null)
{
$this->resource = $resource;
$this->exists = $exists;
}
/**
* {@inheritdoc}
*/
public function __toString()
{
return $this->resource;
}
/**
* @return string The file path to the resource
*/
public function getResource()
{
return $this->resource;
}
/**
* {@inheritdoc}
*
* @throws \ReflectionException when a parent class/interface/trait is not found
*/
public function isFresh($timestamp)
{
$loaded = class_exists($this->resource, false) || interface_exists($this->resource, false) || trait_exists($this->resource, false);
if (null !== $exists = &self::$existsCache[(int) (0 >= $timestamp)][$this->resource]) {
$exists = $exists || $loaded;
} elseif (!$exists = $loaded) {
if (!self::$autoloadLevel++) {
spl_autoload_register(__CLASS__.'::throwOnRequiredClass');
}
$autoloadedClass = self::$autoloadedClass;
self::$autoloadedClass = $this->resource;
try {
$exists = class_exists($this->resource) || interface_exists($this->resource, false) || trait_exists($this->resource, false);
} catch (\ReflectionException $e) {
if (0 >= $timestamp) {
unset(self::$existsCache[1][$this->resource]);
throw $e;
}
} finally {
self::$autoloadedClass = $autoloadedClass;
if (!--self::$autoloadLevel) {
spl_autoload_unregister(__CLASS__.'::throwOnRequiredClass');
}
}
}
if (null === $this->exists) {
$this->exists = $exists;
}
return $this->exists xor !$exists;
}
/**
* {@inheritdoc}
*/
public function serialize()
{
if (null === $this->exists) {
$this->isFresh(0);
}
return serialize(array($this->resource, $this->exists));
}
/**
* {@inheritdoc}
*/
public function unserialize($serialized)
{
list($this->resource, $this->exists) = unserialize($serialized);
}
/**
* @throws \ReflectionException When $class is not found and is required
*/
private static function throwOnRequiredClass($class)
{
if (self::$autoloadedClass === $class) {
return;
}
$e = new \ReflectionException("Class $class not found");
$trace = $e->getTrace();
$autoloadFrame = array(
'function' => 'spl_autoload_call',
'args' => array($class),
);
$i = 1 + array_search($autoloadFrame, $trace, true);
if (isset($trace[$i]['function']) && !isset($trace[$i]['class'])) {
switch ($trace[$i]['function']) {
case 'get_class_methods':
case 'get_class_vars':
case 'get_parent_class':
case 'is_a':
case 'is_subclass_of':
case 'class_exists':
case 'class_implements':
case 'class_parents':
case 'trait_exists':
case 'defined':
case 'interface_exists':
case 'method_exists':
case 'property_exists':
case 'is_callable':
return;
}
$props = array(
'file' => $trace[$i]['file'],
'line' => $trace[$i]['line'],
'trace' => \array_slice($trace, 1 + $i),
);
foreach ($props as $p => $v) {
$r = new \ReflectionProperty('Exception', $p);
$r->setAccessible(true);
$r->setValue($e, $v);
}
}
throw $e;
}
}