Neos\Flow\ResourceManagement\Storage\PackageStorage::getObjectsByPathPattern PHP Method

    public function getObjectsByPathPattern($pattern, callable $callback = null)
    {
        $directories = [];
        if (strpos($pattern, '/') !== false) {
            list($packageKeyPattern, $directoryPattern) = explode('/', $pattern, 2);
        } else {
            $packageKeyPattern = $pattern;
            $directoryPattern = '*';
        }
        // $packageKeyPattern can be used in a future implementation to filter by package key
        $packages = $this->packageManager->getActivePackages();
        foreach ($packages as $packageKey => $package) {
            /** @var PackageInterface $package */
            if ($directoryPattern === '*') {
                $directories[$packageKey][] = $package->getPackagePath();
            } else {
                $directories[$packageKey] = glob($package->getPackagePath() . $directoryPattern, GLOB_ONLYDIR);
            }
        }
        $iteration = 0;
        foreach ($directories as $packageKey => $packageDirectories) {
            foreach ($packageDirectories as $directoryPath) {
                foreach (Files::getRecursiveDirectoryGenerator($directoryPath) as $resourcePathAndFilename) {
                    $pathInfo = UnicodeFunctions::pathinfo($resourcePathAndFilename);
                    $object = new StorageObject();
                    $object->setFilename($pathInfo['basename']);
                    $object->setSha1(sha1_file($resourcePathAndFilename));
                    $object->setMd5(md5_file($resourcePathAndFilename));
                    $object->setFileSize(filesize($resourcePathAndFilename));
                    if (isset($pathInfo['dirname'])) {
                        list(, $path) = explode('/', str_replace($packages[$packageKey]->getResourcesPath(), '', $pathInfo['dirname']), 2);
                        $object->setRelativePublicationPath($packageKey . '/' . $path . '/');
                    }
                    $object->setStream(function () use($resourcePathAndFilename) {
                        return fopen($resourcePathAndFilename, 'r');
                    });
                    (yield $object);
                    if (is_callable($callback)) {
                        call_user_func($callback, $iteration, $object);
                    }
                    $iteration++;
                }
            }
        }
    }