diff --git a/nextcloud/latest/Streamer.php b/nextcloud/latest/Streamer.php new file mode 100644 index 000000000..677856b29 --- /dev/null +++ b/nextcloud/latest/Streamer.php @@ -0,0 +1,169 @@ + + * @author Thomas Müller + * @author Victor Dubiniuk + * + * @license AGPL-3.0 + * + * This code is free software: you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License, version 3, + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License, version 3, + * along with this program. If not, see + * + */ + +namespace OC; + +use OCP\IRequest; +use ownCloud\TarStreamer\TarStreamer; +use ZipStreamer\ZipStreamer; + +class Streamer { + // array of regexp. Matching user agents will get tar instead of zip + private $preferTarFor = [ '/macintosh|mac os x/i' ]; + + // streamer instance + private $streamerInstance; + + /** + * Streamer constructor. + * + * @param IRequest $request + * @param int $size The size of the files in bytes + * @param int $numberOfFiles The number of files (and directories) that will + * be included in the streamed file + */ + public function __construct(IRequest $request, int $size, int $numberOfFiles){ + + /** + * zip32 constraints for a basic (without compression, volumes nor + * encryption) zip file according to the Zip specification: + * - No file size is larger than 4 bytes (file size < 4294967296); see + * 4.4.9 uncompressed size + * - The size of all files plus their local headers is not larger than + * 4 bytes; see 4.4.16 relative offset of local header and 4.4.24 + * offset of start of central directory with respect to the starting + * disk number + * - The total number of entries (files and directories) in the zip file + * is not larger than 2 bytes (number of entries < 65536); see 4.4.22 + * total number of entries in the central dir + * - The size of the central directory is not larger than 4 bytes; see + * 4.4.23 size of the central directory + * + * Due to all that, zip32 is used if the size is below 4GB and there are + * less than 65536 files; the margin between 4*1000^3 and 4*1024^3 + * should give enough room for the extra zip metadata. Technically, it + * would still be possible to create an invalid zip32 file (for example, + * a zip file from files smaller than 4GB with a central directory + * larger than 4GiB), but it should not happen in the real world. + */ + if ($size < 4 * 1000 * 1000 * 1000 && $numberOfFiles < 65536) { + $this->streamerInstance = new ZipStreamer(['zip64' => true]); + } else if ($request->isUserAgent($this->preferTarFor)) { + $this->streamerInstance = new TarStreamer(); + } else { + $this->streamerInstance = new ZipStreamer(['zip64' => PHP_INT_SIZE !== 4]); + } + } + + /** + * Send HTTP headers + * @param string $name + */ + public function sendHeaders($name){ + $extension = $this->streamerInstance instanceof ZipStreamer ? '.zip' : '.tar'; + $fullName = $name . $extension; + $this->streamerInstance->sendHeaders($fullName); + } + + /** + * Stream directory recursively + * @param string $dir + * @param string $internalDir + */ + public function addDirRecursive($dir, $internalDir='') { + $dirname = basename($dir); + $rootDir = $internalDir . $dirname; + if (!empty($rootDir)) { + $this->streamerInstance->addEmptyDir($rootDir); + } + $internalDir .= $dirname . '/'; + // prevent absolute dirs + $internalDir = ltrim($internalDir, '/'); + + $files= \OC\Files\Filesystem::getDirectoryContent($dir); + foreach($files as $file) { + $filename = $file['name']; + $file = $dir . '/' . $filename; + if(\OC\Files\Filesystem::is_file($file)) { + $filesize = \OC\Files\Filesystem::filesize($file); + $fileTime = \OC\Files\Filesystem::filemtime($file); + $fh = \OC\Files\Filesystem::fopen($file, 'r'); + $this->addFileFromStream($fh, $internalDir . $filename, $filesize, $fileTime); + fclose($fh); + }elseif(\OC\Files\Filesystem::is_dir($file)) { + $this->addDirRecursive($file, $internalDir); + } + } + } + + /** + * Add a file to the archive at the specified location and file name. + * + * @param string $stream Stream to read data from + * @param string $internalName Filepath and name to be used in the archive. + * @param int $size Filesize + * @param int|bool $time File mtime as int, or false + * @return bool $success + */ + public function addFileFromStream($stream, $internalName, $size, $time) { + $options = []; + if ($time) { + $options = [ + 'timestamp' => $time + ]; + } + + if ($this->streamerInstance instanceof ZipStreamer) { + return $this->streamerInstance->addFileFromStream($stream, $internalName, $options); + } else { + return $this->streamerInstance->addFileFromStream($stream, $internalName, $size, $options); + } + } + + /** + * Add an empty directory entry to the archive. + * + * @param string $dirName Directory Path and name to be added to the archive. + * @return bool $success + */ + public function addEmptyDir($dirName){ + return $this->streamerInstance->addEmptyDir($dirName); + } + + /** + * Close the archive. + * A closed archive can no longer have new files added to it. After + * closing, the file is completely written to the output stream. + * @return bool $success + */ + public function finalize(){ + return $this->streamerInstance->finalize(); + } +}