Merge pull request #24226 from owncloud/files_psr4

Move \OC\Files to PSR-4

6 files changed, 1163 insertions, 0 deletions

diff --git a/lib/private/Files/Stream/Close.php b/lib/private/Files/Stream/Close.php
new file mode 100644
index 00000000000..1c9b30705dd
--- /dev/null
+++ b/lib/private/Files/Stream/Close.php
@@ -0,0 +1,118 @@
+<?php
+/**
+ * @author Jörn Friedrich Dreyer <jfd@butonic.de>
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Robin Appelman <icewind@owncloud.com>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @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\Files\Stream;
+
+/**
+ * stream wrapper that provides a callback on stream close
+ */
+class Close {
+	private static $callBacks = array();
+	private $path = '';
+	private $source;
+	private static $open = array();
+
+	public function stream_open($path, $mode, $options, &$opened_path) {
+		$path = substr($path, strlen('close://'));
+		$this->path = $path;
+		$this->source = fopen($path, $mode);
+		if (is_resource($this->source)) {
+			$this->meta = stream_get_meta_data($this->source);
+		}
+		self::$open[] = $path;
+		return is_resource($this->source);
+	}
+
+	public function stream_seek($offset, $whence = SEEK_SET) {
+		return fseek($this->source, $offset, $whence) === 0;
+	}
+
+	public function stream_tell() {
+		return ftell($this->source);
+	}
+
+	public function stream_read($count) {
+		return fread($this->source, $count);
+	}
+
+	public function stream_write($data) {
+		return fwrite($this->source, $data);
+	}
+
+	public function stream_set_option($option, $arg1, $arg2) {
+		switch ($option) {
+			case STREAM_OPTION_BLOCKING:
+				stream_set_blocking($this->source, $arg1);
+				break;
+			case STREAM_OPTION_READ_TIMEOUT:
+				stream_set_timeout($this->source, $arg1, $arg2);
+				break;
+			case STREAM_OPTION_WRITE_BUFFER:
+				stream_set_write_buffer($this->source, $arg1, $arg2);
+		}
+	}
+
+	public function stream_stat() {
+		return fstat($this->source);
+	}
+
+	public function stream_lock($mode) {
+		flock($this->source, $mode);
+	}
+
+	public function stream_flush() {
+		return fflush($this->source);
+	}
+
+	public function stream_eof() {
+		return feof($this->source);
+	}
+
+	public function url_stat($path) {
+		$path = substr($path, strlen('close://'));
+		if (file_exists($path)) {
+			return stat($path);
+		} else {
+			return false;
+		}
+	}
+
+	public function stream_close() {
+		fclose($this->source);
+		if (isset(self::$callBacks[$this->path])) {
+			call_user_func(self::$callBacks[$this->path], $this->path);
+		}
+	}
+
+	public function unlink($path) {
+		$path = substr($path, strlen('close://'));
+		return unlink($path);
+	}
+
+	/**
+	 * @param string $path
+	 */
+	public static function registerCallback($path, $callback) {
+		self::$callBacks[$path] = $callback;
+	}
+}
diff --git a/lib/private/Files/Stream/Dir.php b/lib/private/Files/Stream/Dir.php
new file mode 100644
index 00000000000..7489ee683a2
--- /dev/null
+++ b/lib/private/Files/Stream/Dir.php
@@ -0,0 +1,66 @@
+<?php
+/**
+ * @author Jörn Friedrich Dreyer <jfd@butonic.de>
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Robin Appelman <icewind@owncloud.com>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @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\Files\Stream;
+
+class Dir {
+	private static $dirs = array();
+	private $name;
+	private $index;
+
+	public function dir_opendir($path, $options) {
+		$this->name = substr($path, strlen('fakedir://'));
+		$this->index = 0;
+		if (!isset(self::$dirs[$this->name])) {
+			self::$dirs[$this->name] = array();
+		}
+		return true;
+	}
+
+	public function dir_readdir() {
+		if ($this->index >= count(self::$dirs[$this->name])) {
+			return false;
+		}
+		$filename = self::$dirs[$this->name][$this->index];
+		$this->index++;
+		return $filename;
+	}
+
+	public function dir_closedir() {
+		$this->name = '';
+		return true;
+	}
+
+	public function dir_rewinddir() {
+		$this->index = 0;
+		return true;
+	}
+
+	/**
+	 * @param string $path
+	 * @param string[] $content
+	 */
+	public static function register($path, $content) {
+		self::$dirs[$path] = $content;
+	}
+}
diff --git a/lib/private/Files/Stream/Encryption.php b/lib/private/Files/Stream/Encryption.php
new file mode 100644
index 00000000000..772c9769bf7
--- /dev/null
+++ b/lib/private/Files/Stream/Encryption.php
@@ -0,0 +1,500 @@
+<?php
+/**
+ * @author Björn Schießle <schiessle@owncloud.com>
+ * @author jknockaert <jasper@knockaert.nl>
+ * @author Lukas Reschke <lukas@owncloud.com>
+ * @author Roeland Jago Douma <rullzer@owncloud.com>
+ * @author Thomas Müller <thomas.mueller@tmit.eu>
+ * @author Vincent Petry <pvince81@owncloud.com>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @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\Files\Stream;
+
+use Icewind\Streams\Wrapper;
+use OC\Encryption\Exceptions\EncryptionHeaderKeyExistsException;
+
+class Encryption extends Wrapper {
+
+	/** @var \OC\Encryption\Util */
+	protected $util;
+
+	/** @var \OC\Encryption\File */
+	protected $file;
+
+	/** @var \OCP\Encryption\IEncryptionModule */
+	protected $encryptionModule;
+
+	/** @var \OC\Files\Storage\Storage */
+	protected $storage;
+
+	/** @var \OC\Files\Storage\Wrapper\Encryption */
+	protected $encryptionStorage;
+
+	/** @var string */
+	protected $internalPath;
+
+	/** @var string */
+	protected $cache;
+
+	/** @var integer */
+	protected $size;
+
+	/** @var integer */
+	protected $position;
+
+	/** @var integer */
+	protected $unencryptedSize;
+
+	/** @var integer */
+	protected $headerSize;
+
+	/** @var integer */
+	protected $unencryptedBlockSize;
+
+	/** @var array */
+	protected $header;
+
+	/** @var string */
+	protected $fullPath;
+
+	/** @var  bool */
+	protected $signed;
+
+	/**
+	 * header data returned by the encryption module, will be written to the file
+	 * in case of a write operation
+	 *
+	 * @var array
+	 */
+	protected $newHeader;
+
+	/**
+	 * user who perform the read/write operation null for public access
+	 *
+	 * @var string
+	 */
+	protected $uid;
+
+	/** @var bool */
+	protected $readOnly;
+
+	/** @var bool */
+	protected $writeFlag;
+
+	/** @var array */
+	protected $expectedContextProperties;
+
+	public function __construct() {
+		$this->expectedContextProperties = array(
+			'source',
+			'storage',
+			'internalPath',
+			'fullPath',
+			'encryptionModule',
+			'header',
+			'uid',
+			'file',
+			'util',
+			'size',
+			'unencryptedSize',
+			'encryptionStorage',
+			'headerSize',
+			'signed'
+		);
+	}
+
+
+	/**
+	 * Wraps a stream with the provided callbacks
+	 *
+	 * @param resource $source
+	 * @param string $internalPath relative to mount point
+	 * @param string $fullPath relative to data/
+	 * @param array $header
+	 * @param string $uid
+	 * @param \OCP\Encryption\IEncryptionModule $encryptionModule
+	 * @param \OC\Files\Storage\Storage $storage
+	 * @param \OC\Files\Storage\Wrapper\Encryption $encStorage
+	 * @param \OC\Encryption\Util $util
+	 * @param \OC\Encryption\File $file
+	 * @param string $mode
+	 * @param int $size
+	 * @param int $unencryptedSize
+	 * @param int $headerSize
+	 * @param bool $signed
+	 * @param string $wrapper stream wrapper class
+	 * @return resource
+	 *
+	 * @throws \BadMethodCallException
+	 */
+	public static function wrap($source, $internalPath, $fullPath, array $header,
+								$uid,
+								\OCP\Encryption\IEncryptionModule $encryptionModule,
+								\OC\Files\Storage\Storage $storage,
+								\OC\Files\Storage\Wrapper\Encryption $encStorage,
+								\OC\Encryption\Util $util,
+								 \OC\Encryption\File $file,
+								$mode,
+								$size,
+								$unencryptedSize,
+								$headerSize,
+								$signed,
+								$wrapper =  'OC\Files\Stream\Encryption') {
+
+		$context = stream_context_create(array(
+			'ocencryption' => array(
+				'source' => $source,
+				'storage' => $storage,
+				'internalPath' => $internalPath,
+				'fullPath' => $fullPath,
+				'encryptionModule' => $encryptionModule,
+				'header' => $header,
+				'uid' => $uid,
+				'util' => $util,
+				'file' => $file,
+				'size' => $size,
+				'unencryptedSize' => $unencryptedSize,
+				'encryptionStorage' => $encStorage,
+				'headerSize' => $headerSize,
+				'signed' => $signed
+			)
+		));
+
+		return self::wrapSource($source, $context, 'ocencryption', $wrapper, $mode);
+	}
+
+	/**
+	 * add stream wrapper
+	 *
+	 * @param resource $source
+	 * @param string $mode
+	 * @param resource $context
+	 * @param string $protocol
+	 * @param string $class
+	 * @return resource
+	 * @throws \BadMethodCallException
+	 */
+	protected static function wrapSource($source, $context, $protocol, $class, $mode = 'r+') {
+		try {
+			stream_wrapper_register($protocol, $class);
+			if (@rewinddir($source) === false) {
+				$wrapped = fopen($protocol . '://', $mode, false, $context);
+			} else {
+				$wrapped = opendir($protocol . '://', $context);
+			}
+		} catch (\BadMethodCallException $e) {
+			stream_wrapper_unregister($protocol);
+			throw $e;
+		}
+		stream_wrapper_unregister($protocol);
+		return $wrapped;
+	}
+
+	/**
+	 * Load the source from the stream context and return the context options
+	 *
+	 * @param string $name
+	 * @return array
+	 * @throws \BadMethodCallException
+	 */
+	protected function loadContext($name) {
+		$context = parent::loadContext($name);
+
+		foreach ($this->expectedContextProperties as $property) {
+			if (array_key_exists($property, $context)) {
+				$this->{$property} = $context[$property];
+			} else {
+				throw new \BadMethodCallException('Invalid context, "' . $property . '" options not set');
+			}
+		}
+		return $context;
+
+	}
+
+	public function stream_open($path, $mode, $options, &$opened_path) {
+		$this->loadContext('ocencryption');
+
+		$this->position = 0;
+		$this->cache = '';
+		$this->writeFlag = false;
+		$this->unencryptedBlockSize = $this->encryptionModule->getUnencryptedBlockSize($this->signed);
+
+		if (
+			$mode === 'w'
+			|| $mode === 'w+'
+			|| $mode === 'wb'
+			|| $mode === 'wb+'
+			|| $mode === 'r+'
+			|| $mode === 'rb+'
+		) {
+			$this->readOnly = false;
+		} else {
+			$this->readOnly = true;
+		}
+
+		$sharePath = $this->fullPath;
+		if (!$this->storage->file_exists($this->internalPath)) {
+			$sharePath = dirname($sharePath);
+		}
+
+		$accessList = $this->file->getAccessList($sharePath);
+		$this->newHeader = $this->encryptionModule->begin($this->fullPath, $this->uid, $mode, $this->header, $accessList);
+
+		if (
+			$mode === 'w'
+			|| $mode === 'w+'
+			|| $mode === 'wb'
+			|| $mode === 'wb+'
+		) {
+			// We're writing a new file so start write counter with 0 bytes
+			$this->unencryptedSize = 0;
+			$this->writeHeader();
+			$this->headerSize = $this->util->getHeaderSize();
+			$this->size = $this->headerSize;
+		} else {
+			$this->skipHeader();
+		}
+
+		return true;
+
+	}
+
+	public function stream_eof() {
+		return $this->position >= $this->unencryptedSize;
+	}
+
+	public function stream_read($count) {
+
+		$result = '';
+
+		$count = min($count, $this->unencryptedSize - $this->position);
+		while ($count > 0) {
+			$remainingLength = $count;
+			// update the cache of the current block
+			$this->readCache();
+			// determine the relative position in the current block
+			$blockPosition = ($this->position % $this->unencryptedBlockSize);
+			// if entire read inside current block then only position needs to be updated
+			if ($remainingLength < ($this->unencryptedBlockSize - $blockPosition)) {
+				$result .= substr($this->cache, $blockPosition, $remainingLength);
+				$this->position += $remainingLength;
+				$count = 0;
+				// otherwise remainder of current block is fetched, the block is flushed and the position updated
+			} else {
+				$result .= substr($this->cache, $blockPosition);
+				$this->flush();
+				$this->position += ($this->unencryptedBlockSize - $blockPosition);
+				$count -= ($this->unencryptedBlockSize - $blockPosition);
+			}
+		}
+		return $result;
+
+	}
+
+	public function stream_write($data) {
+
+		$length = 0;
+		// loop over $data to fit it in 6126 sized unencrypted blocks
+		while (isset($data[0])) {
+			$remainingLength = strlen($data);
+
+			// set the cache to the current 6126 block
+			$this->readCache();
+
+			// for seekable streams the pointer is moved back to the beginning of the encrypted block
+			// flush will start writing there when the position moves to another block
+			$positionInFile = (int)floor($this->position / $this->unencryptedBlockSize) *
+				$this->util->getBlockSize() + $this->headerSize;
+			$resultFseek = $this->parentStreamSeek($positionInFile);
+
+			// only allow writes on seekable streams, or at the end of the encrypted stream
+			if (!($this->readOnly) && ($resultFseek || $positionInFile === $this->size)) {
+
+				// switch the writeFlag so flush() will write the block
+				$this->writeFlag = true;
+
+				// determine the relative position in the current block
+				$blockPosition = ($this->position % $this->unencryptedBlockSize);
+				// check if $data fits in current block
+				// if so, overwrite existing data (if any)
+				// update position and liberate $data
+				if ($remainingLength < ($this->unencryptedBlockSize - $blockPosition)) {
+					$this->cache = substr($this->cache, 0, $blockPosition)
+						. $data . substr($this->cache, $blockPosition + $remainingLength);
+					$this->position += $remainingLength;
+					$length += $remainingLength;
+					$data = '';
+					// if $data doesn't fit the current block, the fill the current block and reiterate
+					// after the block is filled, it is flushed and $data is updatedxxx
+				} else {
+					$this->cache = substr($this->cache, 0, $blockPosition) .
+						substr($data, 0, $this->unencryptedBlockSize - $blockPosition);
+					$this->flush();
+					$this->position += ($this->unencryptedBlockSize - $blockPosition);
+					$length += ($this->unencryptedBlockSize - $blockPosition);
+					$data = substr($data, $this->unencryptedBlockSize - $blockPosition);
+				}
+			} else {
+				$data = '';
+			}
+			$this->unencryptedSize = max($this->unencryptedSize, $this->position);
+		}
+		return $length;
+	}
+
+	public function stream_tell() {
+		return $this->position;
+	}
+
+	public function stream_seek($offset, $whence = SEEK_SET) {
+
+		$return = false;
+
+		switch ($whence) {
+			case SEEK_SET:
+				$newPosition = $offset;
+				break;
+			case SEEK_CUR:
+				$newPosition = $this->position + $offset;
+				break;
+			case SEEK_END:
+				$newPosition = $this->unencryptedSize + $offset;
+				break;
+			default:
+				return $return;
+		}
+
+		if ($newPosition > $this->unencryptedSize || $newPosition < 0) {
+			return $return;
+		}
+
+		$newFilePosition = floor($newPosition / $this->unencryptedBlockSize)
+			* $this->util->getBlockSize() + $this->headerSize;
+
+		$oldFilePosition = parent::stream_tell();
+		if ($this->parentStreamSeek($newFilePosition)) {
+			$this->parentStreamSeek($oldFilePosition);
+			$this->flush();
+			$this->parentStreamSeek($newFilePosition);
+			$this->position = $newPosition;
+			$return = true;
+		}
+		return $return;
+
+	}
+
+	public function stream_close() {
+		$this->flush('end');
+		$position = (int)floor($this->position/$this->unencryptedBlockSize);
+		$remainingData = $this->encryptionModule->end($this->fullPath, $position . 'end');
+		if ($this->readOnly === false) {
+			if(!empty($remainingData)) {
+				parent::stream_write($remainingData);
+			}
+			$this->encryptionStorage->updateUnencryptedSize($this->fullPath, $this->unencryptedSize);
+		}
+		return parent::stream_close();
+	}
+
+	/**
+	 * write block to file
+	 * @param string $positionPrefix
+	 */
+	protected function flush($positionPrefix = '') {
+		// write to disk only when writeFlag was set to 1
+		if ($this->writeFlag) {
+			// Disable the file proxies so that encryption is not
+			// automatically attempted when the file is written to disk -
+			// we are handling that separately here and we don't want to
+			// get into an infinite loop
+			$position = (int)floor($this->position/$this->unencryptedBlockSize);
+			$encrypted = $this->encryptionModule->encrypt($this->cache, $position . $positionPrefix);
+			$bytesWritten = parent::stream_write($encrypted);
+			$this->writeFlag = false;
+			// Check whether the write concerns the last block
+			// If so then update the encrypted filesize
+			// Note that the unencrypted pointer and filesize are NOT yet updated when flush() is called
+			// We recalculate the encrypted filesize as we do not know the context of calling flush()
+			$completeBlocksInFile=(int)floor($this->unencryptedSize/$this->unencryptedBlockSize);
+			if ($completeBlocksInFile === (int)floor($this->position/$this->unencryptedBlockSize)) {
+				$this->size = $this->util->getBlockSize() * $completeBlocksInFile;
+				$this->size += $bytesWritten;
+				$this->size += $this->headerSize;
+			}
+		}
+		// always empty the cache (otherwise readCache() will not fill it with the new block)
+		$this->cache = '';
+	}
+
+	/**
+	 * read block to file
+	 */
+	protected function readCache() {
+		// cache should always be empty string when this function is called
+		// don't try to fill the cache when trying to write at the end of the unencrypted file when it coincides with new block
+		if ($this->cache === '' && !($this->position === $this->unencryptedSize && ($this->position % $this->unencryptedBlockSize) === 0)) {
+			// Get the data from the file handle
+			$data = parent::stream_read($this->util->getBlockSize());
+			$position = (int)floor($this->position/$this->unencryptedBlockSize);
+			$numberOfChunks = (int)($this->unencryptedSize / $this->unencryptedBlockSize);
+			if($numberOfChunks === $position) {
+				$position .= 'end';
+			}
+			$this->cache = $this->encryptionModule->decrypt($data, $position);
+		}
+	}
+
+	/**
+	 * write header at beginning of encrypted file
+	 *
+	 * @return integer
+	 * @throws EncryptionHeaderKeyExistsException if header key is already in use
+	 */
+	protected function writeHeader() {
+		$header = $this->util->createHeader($this->newHeader, $this->encryptionModule);
+		return parent::stream_write($header);
+	}
+
+	/**
+	 * read first block to skip the header
+	 */
+	protected function skipHeader() {
+		parent::stream_read($this->headerSize);
+	}
+
+	/**
+	 * call stream_seek() from parent class
+	 *
+	 * @param integer $position
+	 * @return bool
+	 */
+	protected function parentStreamSeek($position) {
+		return parent::stream_seek($position);
+	}
+
+	/**
+	 * @param string $path
+	 * @param array $options
+	 * @return bool
+	 */
+	public function dir_opendir($path, $options) {
+		return false;
+	}
+
+}
diff --git a/lib/private/Files/Stream/OC.php b/lib/private/Files/Stream/OC.php
new file mode 100644
index 00000000000..8439770e8fa
--- /dev/null
+++ b/lib/private/Files/Stream/OC.php
@@ -0,0 +1,153 @@
+<?php
+/**
+ * @author Jörn Friedrich Dreyer <jfd@butonic.de>
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Robin Appelman <icewind@owncloud.com>
+ * @author Robin McCorkell <robin@mccorkell.me.uk>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @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\Files\Stream;
+
+/**
+ * a stream wrappers for ownCloud's virtual filesystem
+ */
+class OC {
+	/**
+	 * @var \OC\Files\View
+	 */
+	static private $rootView;
+
+	private $path;
+
+	/**
+	 * @var resource
+	 */
+	private $dirSource;
+
+	/**
+	 * @var resource
+	 */
+	private $fileSource;
+	private $meta;
+
+	private function setup(){
+		if (!self::$rootView) {
+			self::$rootView = new \OC\Files\View('');
+		}
+	}
+
+	public function stream_open($path, $mode, $options, &$opened_path) {
+		$this->setup();
+		$path = substr($path, strlen('oc://'));
+		$this->path = $path;
+		$this->fileSource = self::$rootView->fopen($path, $mode);
+		if (is_resource($this->fileSource)) {
+			$this->meta = stream_get_meta_data($this->fileSource);
+		}
+		return is_resource($this->fileSource);
+	}
+
+	public function stream_seek($offset, $whence = SEEK_SET) {
+		return fseek($this->fileSource, $offset, $whence) === 0;
+	}
+
+	public function stream_tell() {
+		return ftell($this->fileSource);
+	}
+
+	public function stream_read($count) {
+		return fread($this->fileSource, $count);
+	}
+
+	public function stream_write($data) {
+		return fwrite($this->fileSource, $data);
+	}
+
+	public function stream_set_option($option, $arg1, $arg2) {
+		switch ($option) {
+			case STREAM_OPTION_BLOCKING:
+				stream_set_blocking($this->fileSource, $arg1);
+				break;
+			case STREAM_OPTION_READ_TIMEOUT:
+				stream_set_timeout($this->fileSource, $arg1, $arg2);
+				break;
+			case STREAM_OPTION_WRITE_BUFFER:
+				stream_set_write_buffer($this->fileSource, $arg1, $arg2);
+		}
+	}
+
+	public function stream_stat() {
+		return fstat($this->fileSource);
+	}
+
+	public function stream_lock($mode) {
+		flock($this->fileSource, $mode);
+	}
+
+	public function stream_flush() {
+		return fflush($this->fileSource);
+	}
+
+	public function stream_eof() {
+		return feof($this->fileSource);
+	}
+
+	public function url_stat($path) {
+		$this->setup();
+		$path = substr($path, strlen('oc://'));
+		if (self::$rootView->file_exists($path)) {
+			return self::$rootView->stat($path);
+		} else {
+			return false;
+		}
+	}
+
+	public function stream_close() {
+		fclose($this->fileSource);
+	}
+
+	public function unlink($path) {
+		$this->setup();
+		$path = substr($path, strlen('oc://'));
+		return self::$rootView->unlink($path);
+	}
+
+	public function dir_opendir($path, $options) {
+		$this->setup();
+		$path = substr($path, strlen('oc://'));
+		$this->path = $path;
+		$this->dirSource = self::$rootView->opendir($path);
+		if (is_resource($this->dirSource)) {
+			$this->meta = stream_get_meta_data($this->dirSource);
+		}
+		return is_resource($this->dirSource);
+	}
+
+	public function dir_readdir() {
+		return readdir($this->dirSource);
+	}
+
+	public function dir_closedir() {
+		closedir($this->dirSource);
+	}
+
+	public function dir_rewinddir() {
+		rewinddir($this->dirSource);
+	}
+}
diff --git a/lib/private/Files/Stream/Quota.php b/lib/private/Files/Stream/Quota.php
new file mode 100644
index 00000000000..8d27575c568
--- /dev/null
+++ b/lib/private/Files/Stream/Quota.php
@@ -0,0 +1,156 @@
+<?php
+/**
+ * @author Jörn Friedrich Dreyer <jfd@butonic.de>
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Robin Appelman <icewind@owncloud.com>
+ * @author Vincent Petry <pvince81@owncloud.com>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @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\Files\Stream;
+
+/**
+ * stream wrapper limits the amount of data that can be written to a stream
+ *
+ * usage: void \OC\Files\Stream\Quota::register($id, $stream, $limit)
+ * or:    resource \OC\Files\Stream\Quota::wrap($stream, $limit)
+ */
+class Quota {
+	private static $streams = array();
+
+	/**
+	 * @var resource $source
+	 */
+	private $source;
+
+	/**
+	 * @var int $limit
+	 */
+	private $limit;
+
+	/**
+	 * @param string $id
+	 * @param resource $stream
+	 * @param int $limit
+	 */
+	public static function register($id, $stream, $limit) {
+		self::$streams[$id] = array($stream, $limit);
+	}
+
+	/**
+	 * remove all registered streams
+	 */
+	public static function clear() {
+		self::$streams = array();
+	}
+
+	/**
+	 * @param resource $stream
+	 * @param int $limit
+	 * @return resource
+	 */
+	static public function wrap($stream, $limit) {
+		$id = uniqid();
+		self::register($id, $stream, $limit);
+		$meta = stream_get_meta_data($stream);
+		return fopen('quota://' . $id, $meta['mode']);
+	}
+
+	public function stream_open($path, $mode, $options, &$opened_path) {
+		$id = substr($path, strlen('quota://'));
+		if (isset(self::$streams[$id])) {
+			list($this->source, $this->limit) = self::$streams[$id];
+			return true;
+		} else {
+			return false;
+		}
+	}
+
+	public function stream_seek($offset, $whence = SEEK_SET) {
+		if ($whence === SEEK_END){
+			// go to the end to find out last position's offset
+			$oldOffset = $this->stream_tell();
+			if (fseek($this->source, 0, $whence) !== 0){
+				return false;
+			}
+			$whence = SEEK_SET;
+			$offset = $this->stream_tell() + $offset;
+			$this->limit += $oldOffset - $offset;
+		}
+		else if ($whence === SEEK_SET) {
+			$this->limit += $this->stream_tell() - $offset;
+		} else {
+			$this->limit -= $offset;
+		}
+		// this wrapper needs to return "true" for success.
+		// the fseek call itself returns 0 on succeess
+		return fseek($this->source, $offset, $whence) === 0;
+	}
+
+	public function stream_tell() {
+		return ftell($this->source);
+	}
+
+	public function stream_read($count) {
+		$this->limit -= $count;
+		return fread($this->source, $count);
+	}
+
+	public function stream_write($data) {
+		$size = strlen($data);
+		if ($size > $this->limit) {
+			$data = substr($data, 0, $this->limit);
+			$size = $this->limit;
+		}
+		$this->limit -= $size;
+		return fwrite($this->source, $data);
+	}
+
+	public function stream_set_option($option, $arg1, $arg2) {
+		switch ($option) {
+			case STREAM_OPTION_BLOCKING:
+				stream_set_blocking($this->source, $arg1);
+				break;
+			case STREAM_OPTION_READ_TIMEOUT:
+				stream_set_timeout($this->source, $arg1, $arg2);
+				break;
+			case STREAM_OPTION_WRITE_BUFFER:
+				stream_set_write_buffer($this->source, $arg1, $arg2);
+		}
+	}
+
+	public function stream_stat() {
+		return fstat($this->source);
+	}
+
+	public function stream_lock($mode) {
+		return flock($this->source, $mode);
+	}
+
+	public function stream_flush() {
+		return fflush($this->source);
+	}
+
+	public function stream_eof() {
+		return feof($this->source);
+	}
+
+	public function stream_close() {
+		fclose($this->source);
+	}
+}
diff --git a/lib/private/Files/Stream/StaticStream.php b/lib/private/Files/Stream/StaticStream.php
new file mode 100644
index 00000000000..7aacf7a9fe4
--- /dev/null
+++ b/lib/private/Files/Stream/StaticStream.php
@@ -0,0 +1,170 @@
+<?php
+/**
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Robin Appelman <icewind@owncloud.com>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @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\Files\Stream;
+
+class StaticStream {
+	const MODE_FILE = 0100000;
+
+	public $context;
+	protected static $data = array();
+
+	protected $path = '';
+	protected $pointer = 0;
+	protected $writable = false;
+
+	public function stream_close() {
+	}
+
+	public function stream_eof() {
+		return $this->pointer >= strlen(self::$data[$this->path]);
+	}
+
+	public function stream_flush() {
+	}
+
+	public static function clear() {
+		self::$data = array();
+	}
+
+	public function stream_open($path, $mode, $options, &$opened_path) {
+		switch ($mode[0]) {
+			case 'r':
+				if (!isset(self::$data[$path])) return false;
+				$this->path = $path;
+				$this->writable = isset($mode[1]) && $mode[1] == '+';
+				break;
+			case 'w':
+				self::$data[$path] = '';
+				$this->path = $path;
+				$this->writable = true;
+				break;
+			case 'a':
+				if (!isset(self::$data[$path])) self::$data[$path] = '';
+				$this->path = $path;
+				$this->writable = true;
+				$this->pointer = strlen(self::$data[$path]);
+				break;
+			case 'x':
+				if (isset(self::$data[$path])) return false;
+				$this->path = $path;
+				$this->writable = true;
+				break;
+			case 'c':
+				if (!isset(self::$data[$path])) self::$data[$path] = '';
+				$this->path = $path;
+				$this->writable = true;
+				break;
+			default:
+				return false;
+		}
+		$opened_path = $this->path;
+		return true;
+	}
+
+	public function stream_read($count) {
+		$bytes = min(strlen(self::$data[$this->path]) - $this->pointer, $count);
+		$data = substr(self::$data[$this->path], $this->pointer, $bytes);
+		$this->pointer += $bytes;
+		return $data;
+	}
+
+	public function stream_seek($offset, $whence = SEEK_SET) {
+		$len = strlen(self::$data[$this->path]);
+		switch ($whence) {
+			case SEEK_SET:
+				if ($offset <= $len) {
+					$this->pointer = $offset;
+					return true;
+				}
+				break;
+			case SEEK_CUR:
+				if ($this->pointer + $offset <= $len) {
+					$this->pointer += $offset;
+					return true;
+				}
+				break;
+			case SEEK_END:
+				if ($len + $offset <= $len) {
+					$this->pointer = $len + $offset;
+					return true;
+				}
+				break;
+		}
+		return false;
+	}
+
+	public function stream_stat() {
+		return $this->url_stat($this->path);
+	}
+
+	public function stream_tell() {
+		return $this->pointer;
+	}
+
+	public function stream_write($data) {
+		if (!$this->writable) return 0;
+		$size = strlen($data);
+		if ($this->stream_eof()) {
+			self::$data[$this->path] .= $data;
+		} else {
+			self::$data[$this->path] = substr_replace(
+				self::$data[$this->path],
+				$data,
+				$this->pointer
+			);
+		}
+		$this->pointer += $size;
+		return $size;
+	}
+
+	public function unlink($path) {
+		if (isset(self::$data[$path])) {
+			unset(self::$data[$path]);
+		}
+		return true;
+	}
+
+	public function url_stat($path) {
+		if (isset(self::$data[$path])) {
+			$size = strlen(self::$data[$path]);
+			$time = time();
+			$data = array(
+				'dev' => 0,
+				'ino' => 0,
+				'mode' => self::MODE_FILE | 0777,
+				'nlink' => 1,
+				'uid' => 0,
+				'gid' => 0,
+				'rdev' => '',
+				'size' => $size,
+				'atime' => $time,
+				'mtime' => $time,
+				'ctime' => $time,
+				'blksize' => -1,
+				'blocks' => -1,
+			);
+			return array_values($data) + $data;
+		}
+		return false;
+	}
+}