nextcloud/lib/private/Streamer.php

166 lines
5.6 KiB
PHP

<?php
/**
* @copyright Copyright (c) 2016, ownCloud, Inc.
*
* @author Daniel Calviño Sánchez <danxuliu@gmail.com>
* @author Joas Schilling <coding@schilljs.com>
* @author Roeland Jago Douma <roeland@famdouma.nl>
* @author Thomas Müller <thomas.mueller@tmit.eu>
* @author Victor Dubiniuk <dubiniuk@owncloud.com>
*
* @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 <http://www.gnu.org/licenses/>
*
*/
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) {
$this->streamerInstance = new ZipStreamer(['zip64' => false]);
} else if ($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();
}
}