composer/src/Composer/Package/Archiver/ZipArchiver.php

<?php

/*
 * This file is part of Composer.
 *
 * (c) Nils Adermann <naderman@naderman.de>
 *     Jordi Boggiano <j.boggiano@seld.be>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Composer\Package\Archiver;

use ZipArchive;

/**
 * @author Jan Prieser <jan@prieser.net>
 */
class ZipArchiver implements ArchiverInterface
{
    protected static $formats = array(
        'zip' => 1
    );

    /**
     * {@inheritdoc}
     */
    public function archive($sources, $target, $format, array $excludes = array())
    {
        $sources = realpath($sources);
        $zip = new ZipArchive();
        $res = $zip->open($target, ZipArchive::CREATE);
        if ($res === true) {
            $files = new ArchivableFilesFinder($sources, $excludes);
            foreach($files as $file) {
                /** @var $file \SplFileInfo */
                $filepath = $file->getPath()."/".$file->getFilename();
                $localname = str_replace($sources."/", '', $filepath);
                $zip->addFile($filepath, $localname);
            }
            if ($zip->close()) {
                return $target;
            }
        }
        $message = sprintf("Could not create archive '%s' from '%s': %s",
            $target,
            $sources,
            $zip->getStatusString()
        );
        throw new \RuntimeException($message);
    }

    /**
     * {@inheritdoc}
     */
    public function supports($format, $sourceType)
    {
        return isset(static::$formats[$format]) && $this->compressionAvailable();
    }

    private function compressionAvailable() {
        return class_exists('ZipArchive');
    }
}