LazyClassMapLoader.php

<?php

namespace Symfony\Component\ClassLoader;

class LazyClassMapLoader
{
    private $classMap = array();
    private $collectedClasses = array();
    private $loader;
    private $path;
    private $registered;

    public function __construct($path, $loader)
    {
        if (!method_exists($loader, 'findFile')) {
            throw new \InvalidArgumentException('The class finder must implement a "findFile" method.');
        }

        if (file_exists($path)) {
            $classMap = require $path;
            if ($classMap && is_array($classMap)) {
                $this->classMap = $classMap;
            }
        }

        $this->path = $path;
        $this->loader = $loader;
    }

    public function register($prepend = true)
    {
        spl_autoload_register(array($this, 'loadClass'), true, $prepend);
        register_shutdown_function(array($this, 'dump'));

        $this->registered = true;
    }

    public function unregister()
    {
        spl_autoload_unregister(array($this, 'loadClass'));

        $this->registered = false;
    }

    public function loadClass($class)
    {
        if ($file = $this->findFile($class)) {
            include $file;

            return true;
        }
    }

    public function findFile($class)
    {
        if (isset($this->classMap[$class])) {
            return $this->classMap[$class];
        }

        if ($file = $this->loader->findFile($class)) {
            return $this->collectedClasses[$class] = $file;
        }

        return false;
    }

    public function dump()
    {
        if (!$this->registered || !$this->collectedClasses) {
            return;
        }

        $tmpFile = tempnam(dirname($this->path), basename($this->path));
        $handle = @fopen($tmpFile, 'w');

        $classes = array_merge($this->classMap, $this->collectedClasses);
        @fwrite($handle, sprintf('<?php return %s;', var_export($classes, true)));
        @fclose($handle);

        if ($classes != file_get_contents($tmpFile)) {
            return;
        }

        if (false === @rename($tmpFile, $this->path)) {
            return;
        }

        @chmod($this->path, 0666 & ~umask());
    }

    public function __call($method, $arguments)
    {
        return call_user_func_array(array($this->loader, $method), $arguments);
    }
}